title: Visalia, California

text: The United States Postal Service operates the Town Center Post Office at 111 West Acequia Avenue, the Visalia Post Office at 2345 West Beech Avenue, and the Millennium Post Office at 100 North Akers Street. The Town Center Post Office received listing in the National Register of Historic Places on January 11, 1985.


title: Prime meridian (Greenwich)

text: The historic prime meridian or Greenwich meridian is a geographical reference line that passes through the Royal Observatory, Greenwich, in London, England. The modern IERS Reference Meridian widely used today is based on the Greenwich meridian, but differs slightly from it. This prime meridian (at the time, one of many) was first established by Sir George Airy in 1851, and by 1884, over two-thirds of all ships and tonnage used it as the reference meridian on their charts and maps. In October of that year, at the behest of US President Chester A. Arthur, 41 delegates from 25 nations met in Washington, D.C., United States, for the International Meridian Conference. This conference selected the meridian passing through Greenwich as the world standard prime meridian due to its popularity. However, France abstained from the vote, and French maps continued to use the Paris meridian for several decades. In the 18th century, London lexicographer Malachy Postlethwayt published his African maps showing the "Meridian of London" intersecting the Equator a few degrees west of the later meridian and Accra, Ghana.


title: Prime meridian (Greenwich)

text: The plane of the prime meridian is parallel to the local gravity vector at the Airy transit circle () of the Greenwich observatory. The prime meridian was therefore long symbolised by a brass strip in the courtyard, now replaced by stainless steel, and since 16 December 1999, it has been marked by a powerful green laser shining north across the London night sky.


title: Prime meridian (Greenwich)

text: Global Positioning System (GPS) receivers show that the marking strip for the prime meridian at Greenwich is not exactly at zero degrees, zero minutes, and zero seconds but at approximately 5.3 seconds of arc to the west of the meridian (meaning that the meridian appears to be 102 metres east). In the past, this offset has been attributed to the establishment of reference meridians for space-based location systems such as WGS 84 (which GPS relies on) or that errors gradually crept into the International Time Bureau timekeeping process. The actual reason for the discrepancy is that the difference between precise GNSS coordinates and astronomically determined coordinates everywhere remains a localized gravity effect due to vertical deflection; thus, no systematic rotation of global longitudes occurred between the former astronomical system and the current geodetic system.


title: Prime meridian (Greenwich)

text: Before the establishment of a common meridian, most maritime countries established their own prime meridian, usually passing through the country in question. In 1721, Great Britain established its own meridian passing through an early transit circle at the newly established Royal Observatory at Greenwich. The meridian was moved around 10 metres or so east on three occasions as transit circles with newer and better instruments were built, on each occasion next door to the existing one. This was to allow uninterrupted observation during each new construction. The final meridian was established as an imaginary line from the north pole to the south pole passing through the Airy transit circle. This became the United Kingdom's meridian in 1851. For all practical purposes of the period, the changes as the meridian was moved went unnoticed.


title: Prime meridian (Greenwich)

text: Transit instruments are installed to be perpendicular to the local level (which is a plane perpendicular to a plumb line). In 1884, the International Meridian Conference took place in Washington, D.C. to establish an internationally recognised single meridian. The meridian chosen was that which passed through the Airy transit circle at Greenwich, and it became the prime meridian of the world.


title: Prime meridian (Greenwich)

text: At around the time of this conference, scientists were making measurements to determine the deflection of the vertical on a large scale. One might expect that plumb lines set up in various locations, if extended downward, would all pass through a single point, the centre of the Earth, but this is not the case, primarily due to the Earth being an ellipsoid, not a sphere. The downward extended plumb lines don't even all intersect the rotation axis of the Earth; this much smaller effect is due to the uneven distribution of the Earth's mass. To make computations feasible, scientists defined ellipsoids of revolution, more closely emulating the shape of the Earth, modified for a particular zone; a published ellipsoid would be a good base line for measurements. The difference between the direction of a plumb line or vertical, and a line perpendicular to the surface of the ellipsoid of revolution a "normal" to said ellipsoid at a particular observatory, is the deflection of the vertical.


title: Prime meridian (Greenwich)

text: When the Airy transit circle was built, a mercury basin was used to align the telescope to the perpendicular. Thus the circle was aligned with the local vertical or plumb line, which is deflected slightly from the normal, or line perpendicular, to the reference ellipsoid used to define geodetic latitude and longitude in the International Terrestrial Reference Frame (which is nearly the same as the WGS-84 system used by GPS). While Airy's local vertical, set by the "apparent" centre of gravity of the earth still points to (aligns with) the modern celestial meridian (the intersection of the prime meridian plane with the celestial sphere), it does not pass through the Earth's rotation axis. As a result of this, the ITRF zero meridian, defined by a plane passing through the Earth's rotation axis, is 102.478 metres to the east of the prime meridian. A 2015 analysis by Malys "et al." shows the offset between the former and the latter can be explained by this deflection of the vertical alone; other possible sources of the offset that have been proposed in the past are smaller than the current uncertainty in the deflection of the vertical, locally. The astronomical longitude of the Greenwich prime meridian was found to be 0.19″ ± 0.47″ East, i.e. the plane defined by the local vertical on the Greenwich prime meridian and the plane passing through the Earth's rotation axis on the ITRF zero meridian are effectively parallel. Claims, such as that on the BBC website, that the gap between astronomical and geodetic coordinates means that "any" measurements of transit time across the IRTF zero meridian will occur precisely 0.352 seconds (or 0.353 sidereal seconds) before the transit across the "intended meridian" are based on a failure of understanding. The explanation by Malys "et al". on the other hand is more studied and correct.


title: Project K (film)

text: Project K is the working title of an upcoming Indian science fiction action film written and directed by Nag Ashwin. Produced by Vyjayanthi Movies, the film is simultaneously shot in Telugu and Hindi languages. It stars Amitabh Bachchan, Prabhas, Deepika Padukone and Disha Patani.


title: Project K (film)

text: The film was announced in February 2020 coinciding with 50 years of Vyjayanthi Movies. The film's production was delayed by a year due to the COVID-19 pandemic. Filming began in July 2021 at a futuristic set erected at Ramoji Film City in Hyderabad. Made at an estimated budget of , "Project K" is one of the most expensive Indian film ever made. The film's music score is composed by Mickey J. Meyer with cinematography by Dani Sanchez Lopez.


title: Project K (film)

text: Following the 2018 biographical film "Mahanati", director Nag Ashwin stated in August 2019 that he has been working on an original story and screenplay for a long time which would go on floors soon. The same month, Vyjayanthi Movies revealed their plans to begin Ashwin's film in September that year and invited visual artists, designers and writers to join the production.


title: Project K (film)

text: Vyjayanthi Movies officially announced in February 2020 that their next film with Ashwin would star Prabhas. It is intended to mark 50 years since the establishment of their studio. The film is being produced by Ashwin's father-in-law, C. Aswani Dutt.


title: Project K (film)

text: In July 2020, Hindi film indian actress Deepika Padukone was signed to play the lead role opposite Prabhas. Padukone felt that she was "beyond thrilled" to join the production while Ashwin stated that her character would be "surprise" as it was something which "no mainstream lead has [ever] done before". The film marks Padukone's debut in Telugu cinema. "Bollywood Hungama" reported that her role was initially "not substantial" but was improved to suit her stardom. In October, Amitabh Bachchan was cast in a full-length role in the film. Ashwin stated that his role was "so important that his character's name was the working title of an early draft". The film would be Bachchan's first full-length role in a Telugu film, following his previous cameo appearance in "Manam" (2014) and "Sye Raa Narasimha Reddy" (2019). In May 2022, Disha Patani joined the cast, marking her return to Telugu cinema after "Loafer" (2015).


title: Project K (film)

text: In August 2020, A. R. Rahman was initially approached to compose music for the film. However, in January 2021, Ashwin retained technicians from his earlier film "Mahanati" (2018), namely, music composer Mickey J. Meyer and cinematographer Dani Sanchez-Lopez. Singeetam Srinivasa Rao joined the project to serve as a mentor. "Project K" serves as the working title of the yet-untitled film.


title: Project K (film)

text: Ashwin stated that "Project K" needed high-end technology and futuristic vehicles to be developed for the film. While they can be recreated using computer-generated imagery (CGI), Ashwin wanted them to feel "authentic and genuine", therefore opted to build these vehicles from scratch with a dedicated team of engineers. In March 2022, Ashwin requested businessman Anand Mahindra to provide technical support to build such type of vehicles. A few days later, Mahindra responded that their company Mahindra & Mahindra would assist the production team from their Mahindra Research Valley campus in Chennai. In July 2021, the makers have erected a futuristic set at Ramoji Film City in Hyderabad where a significant portion of filming is expected to take place.


title: Project K (film)

text: "Project K" is estimated to be mounted at a budget of , making it one of the most expensive Indian films ever made. The film is simultaneously shot in Telugu and Hindi languages.


title: Project K (film)

text: Initially, the film was planned to begin its regular shoot in November 2020, however, it was postponed to the following year due to the advent of the COVID-19 pandemic. Principal photography commenced in Hyderabad in July 2021 on the occasion of Guru Purnima, following a muhurat shot featuring Bachchan. Prabhas and Padukone joined the production in December 2021 and scenes featuring Bachchan, Prabhas and Padukone were shot. Second schedule of the shoot took place in February 2022.


title: Project K (film)

text: Instead of shooting the entire film in a single stretch, the team divided its 80–90 days of shoot into 7–8 days every month. This would allow the production team to take time and prepare the gadgets and property to be used in this science fiction film. Therefore, the production of "Project K" is expected to take longer than usual. DIY Arri Alexa camera is being used to shoot the film, thus making "Project K" the first Indian film to use this technology.


title: Project K (film)

text: Prabhas was expected to start filming his solo portions in April 2022, however, his knee surgery led to a delay of his upcoming projects including "Salaar" and "Project K." 90 per cent of the shoot is being done in Ramoji Film City. In June, Bachchan shot for a scene at Raidurg metro station. In July, Padukone and Prabhas shot for a car chase sequence in Hyderabad. Prabhas completed shooting majority of his portions by the end of this schedule.


title: Project K (film)

text: Principal photography of the film is expected to be completed by January 2023, following which post-production and visual effects works would take around 8 months.


title: Project K (film)

text: In July 2022, producer Dutt stated that they are planning to release "Project K" either on 18 October 2023 or in January 2024. Telangana & Andhra Pradesh release by Geetha Arts, North India release by Pen Marudhar Entertainment and International release by Lyca Productions in association with Tentkotta. Initially aimed for a 2022 release, it was delayed due the COVID-19 pandemic and production works. The film is planned to be released in Telugu, Hindi, Tamil, Malayalam, Kannada and English languages.


title: Glass transition

text: The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rubbery state as the temperature is increased. An amorphous solid that exhibits a glass transition is called a glass. The reverse transition, achieved by supercooling a viscous liquid into the glass state, is called vitrification.


title: Glass transition

text: The glass-transition temperature "T" of a material characterizes the range of temperatures over which this glass transition occurs (as an experimental definition, typically marked as 100 s of relaxation time). It is always lower than the melting temperature, "T", of the crystalline state of the material, if one exists.


title: Glass transition

text: Hard plastics like polystyrene and poly(methyl methacrylate) are used well below their glass transition temperatures, i.e., when they are in their glassy state. Their "T" values are both at around . Rubber elastomers like polyisoprene and polyisobutylene are used above their "T", that is, in the rubbery state, where they are soft and flexible; crosslinking prevents free flow of their molecules, thus endowing rubber with a set shape at room temperature (as opposed to a viscous liquid).


title: Glass transition

text: Despite the change in the physical properties of a material through its glass transition, the transition is not considered a phase transition; rather it is a phenomenon extending over a range of temperature and defined by one of several conventions. Such conventions include a constant cooling rate () and a viscosity threshold of 10 Pa·s, among others. Upon cooling or heating through this glass-transition range, the material also exhibits a smooth step in the thermal-expansion coefficient and in the specific heat, with the location of these effects again being dependent on the history of the material. The question of whether some phase transition underlies the glass transition is a matter of ongoing research.


title: Glass transition

text: The glass transition of a liquid to a solid-like state may occur with either cooling or compression. The transition comprises a smooth increase in the viscosity of a material by as much as 17 orders of magnitude within a temperature range of 500 K without any pronounced change in material structure. The consequence of this dramatic increase is a glass exhibiting solid-like mechanical properties on the timescale of practical observation. This transition is in contrast to the freezing or crystallization transition, which is a first-order phase transition in the Ehrenfest classification and involves discontinuities in thermodynamic and dynamic properties such as volume, energy, and viscosity. In many materials that normally undergo a freezing transition, rapid cooling will avoid this phase transition and instead result in a glass transition at some lower temperature. Other materials, such as many polymers, lack a well defined crystalline state and easily form glasses, even upon very slow cooling or compression. The tendency for a material to form a glass while quenched is called glass forming ability. This ability depends on the composition of the material and can be predicted by the rigidity theory.


title: Glass transition

text: Below the transition temperature range, the glassy structure does not relax in accordance with the cooling rate used. The expansion coefficient for the glassy state is roughly equivalent to that of the crystalline solid. If slower cooling rates are used, the increased time for structural relaxation (or intermolecular rearrangement) to occur may result in a higher density glass product. Similarly, by annealing (and thus allowing for slow structural relaxation) the glass structure in time approaches an equilibrium density corresponding to the supercooled liquid at this same temperature. "T" is located at the intersection between the cooling curve (volume versus temperature) for the glassy state and the supercooled liquid.


title: Glass transition

text: The configuration of the glass in this temperature range changes slowly with time towards the equilibrium structure. The principle of the minimization of the Gibbs free energy provides the thermodynamic driving force necessary for the eventual change. At somewhat higher temperatures than "T", the structure corresponding to equilibrium at any temperature is achieved quite rapidly. In contrast, at considerably lower temperatures, the configuration of the glass remains sensibly stable over increasingly extended periods of time.


title: Glass transition

text: Thus, the liquid-glass transition is not a transition between states of thermodynamic equilibrium. It is widely believed that the true equilibrium state is always crystalline. Glass is believed to exist in a kinetically locked state, and its entropy, density, and so on, depend on the thermal history. Therefore, the glass transition is primarily a dynamic phenomenon. Time and temperature are interchangeable quantities (to some extent) when dealing with glasses, a fact often expressed in the time–temperature superposition principle. On cooling a liquid, "internal degrees of freedom successively fall out of equilibrium". However, there is a longstanding debate whether there is an underlying second-order phase transition in the hypothetical limit of infinitely long relaxation times.


title: Glass transition

text: In a more recent model of glass transition, the glass transition temperature corresponds to the temperature at which the largest openings between the vibrating elements in the liquid matrix become smaller than the smallest cross-sections of the elements or parts of them when the temperature is decreasing. As a result of the fluctuating input of thermal energy into the liquid matrix, the harmonics of the oscillations are constantly disturbed and temporary cavities ("free volume") are created between the elements, the number and size of which depend on the temperature. The glass transition temperature "T" defined in this way is a fixed material constant of the disordered (non-crystalline) state that is dependent only on the pressure. As a result of the increasing inertia of the molecular matrix when approaching "T", the setting of the thermal equilibrium is successively delayed, so that the usual measuring methods for determining the glass transition temperature in principle deliver "T" values that are too high. In principle, the slower the temperature change rate is set during the measurement, the closer the measured "T" value "T" approaches. Techniques such as dynamic mechanical analysis can be used to measure the glass transition temperature.


title: Glass transition

text: Refer to the figure on the bottom right plotting the heat capacity as a function of temperature. In this context, "T" is the temperature corresponding to point A on the curve.


title: Glass transition

text: Different operational definitions of the glass transition temperature "T" are in use, and several of them are endorsed as accepted scientific standards. Nevertheless, all definitions are arbitrary, and all yield different numeric results: at best, values of "T" for a given substance agree within a few kelvins. One definition refers to the viscosity, fixing "T" at a value of 10 poise (or 10 Pa·s). As evidenced experimentally, this value is close to the annealing point of many glasses.


title: Glass transition

text: In contrast to viscosity, the thermal expansion, heat capacity, shear modulus, and many other properties of inorganic glasses show a relatively sudden change at the glass transition temperature. Any such step or kink can be used to define "T". To make this definition reproducible, the cooling or heating rate must be specified.


title: Glass transition

text: The most frequently used definition of "T" uses the energy release on heating in differential scanning calorimetry (DSC, see figure). Typically, the sample is first cooled with 10 K/min and then heated with that same speed.


title: Glass transition

text: Yet another definition of "T" uses the kink in dilatometry (a.k.a. thermal expansion): refer to the figure on the top right. Here, heating rates of are common. The linear sections below and above "T" are colored green. "T" is the temperature at the intersection of the red regression lines.


title: Glass transition

text: Dry nylon-6 has a glass transition temperature of . Nylon-6,6 in the dry state has a glass transition temperature of about . Whereas polyethene has a glass transition range of


title: Glass transition

text: The above are only mean values, as the glass transition temperature depends on the cooling rate and molecular weight distribution and could be influenced by additives. For a semi-crystalline material, such as polyethene that is 60–80% crystalline at room temperature, the quoted glass transition refers to what happens to the amorphous part of the material upon cooling.


title: Glass transition

text: As a liquid is supercooled, the difference in entropy between the liquid and solid phase decreases. By extrapolating the heat capacity of the supercooled liquid below its glass transition temperature, it is possible to calculate the temperature at which the difference in entropies becomes zero. This temperature has been named the Kauzmann temperature.


title: Glass transition

text: If a liquid could be supercooled below its Kauzmann temperature, and it did indeed display a lower entropy than the crystal phase, the consequences would be paradoxical. This Kauzmann paradox has been the subject of much debate and many publications since it was first put forward by Walter Kauzmann in 1948.


title: Glass transition

text: One resolution of the Kauzmann paradox is to say that there must be a phase transition before the entropy of the liquid decreases. In this scenario, the transition temperature is known as the "calorimetric ideal glass transition temperature" "T". In this view, the glass transition is not merely a kinetic effect, i.e. merely the result of fast cooling of a melt, but there is an underlying thermodynamic basis for glass formation. The glass transition temperature:


title: Glass transition

text: The Gibbs–DiMarzio model from 1958 specifically predicts that a supercooled liquid's configurational entropy disappears in the limit formula_2, where the liquid's existence regime ends, its microstructure becomes identical to the crystal's, and their property curves intersect in a true second-order phase transition. This has never been experimentally verified due to the difficulty of realizing a slow enough cooling rate while avoiding accidental crystallization. The Adam–Gibbs model from 1965 suggested a resolution of the Kauzmann paradox according to which the relaxation time diverges at the Kauzmann temperature, implying that one can never equilibrate the metastable supercooled liquid here. A critical discussion of the Kauzmann paradox and the Adam–Gibbs model was given in 2009. Data on several supercooled organic liquids do not confirm the Adam–Gibbs prediction of a diverging relaxation time at any finite temperature, e.g. the Kauzmann temperature.


title: Glass transition

text: There are at least three other possible resolutions to the Kauzmann paradox. It could be that the heat capacity of the supercooled liquid near the Kauzmann temperature smoothly decreases to a smaller value. It could also be that a first order phase transition to another liquid state occurs before the Kauzmann temperature with the heat capacity of this new state being less than that obtained by extrapolation from higher temperature. Finally, Kauzmann himself resolved the entropy paradox by postulating that all supercooled liquids must crystallize before the Kauzmann temperature is reached.


title: Glass transition

text: Silica (the chemical compound SiO) has a number of distinct crystalline forms in addition to the quartz structure. Nearly all of the crystalline forms involve tetrahedral SiO units linked together by "shared vertices" in different arrangements (stishovite, composed of linked SiO octahedra, is the main exception). Si-O bond lengths vary between the different crystal forms. For example, in α-quartz the bond length is , whereas in α-tridymite it ranges from . The Si-O-Si bond angle also varies from 140° in α-tridymite to 144° in α-quartz to 180° in β-tridymite. Any deviations from these standard parameters constitute microstructural differences or variations that represent an approach to an amorphous, vitreous or glassy solid.


title: Glass transition

text: The transition temperature "T" in silicates is related to the energy required to break and re-form covalent bonds in an amorphous (or random network) lattice of covalent bonds. The "T" is clearly influenced by the chemistry of the glass. For example, addition of elements such as B, Na, K or Ca to a silica glass, which have a valency less than 4, helps in breaking up the network structure, thus reducing the "T". Alternatively, P, which has a valency of 5, helps to reinforce an ordered lattice, and thus increases the "T".


title: Glass transition

text: "T" is directly proportional to bond strength, e.g. it depends on quasi-equilibrium thermodynamic parameters of the bonds e.g. on the enthalpy "H" and entropy "S" of configurons – broken bonds: "T" = "H" / ["S" + R ln[(1 − "f")/ "f"] where R is the gas constant and "f" is the percolation threshold. For strong melts such as Si"O" the percolation threshold in the above equation is the universal Scher–Zallen critical density in the 3-D space e.g. "f" = 0.15, however for fragile materials the percolation thresholds are material-dependent and "f" ≪ 1. The enthalpy "H" and the entropy "S" of configurons – broken bonds can be found from available experimental data on viscosity.


title: Glass transition

text: In polymers the glass transition temperature, "T", is often expressed as the temperature at which the Gibbs free energy is such that the activation energy for the cooperative movement of 50 or so elements of the polymer is exceeded . This allows molecular chains to slide past each other when a force is applied. From this definition, we can see that the introduction of relatively stiff chemical groups (such as benzene rings) will interfere with the flowing process and hence increase "T".


title: Glass transition

text: The stiffness of thermoplastics decreases due to this effect (see figure.) When the glass temperature has been reached, the stiffness stays the same for a while, i.e., at or near "E", until the temperature exceeds "T", and the material melts. This region is called the rubber plateau.


title: Glass transition

text: Coming from the low-temperature side, the shear modulus drops by many orders of magnitude at the glass transition temperature "T". A molecular-level mathematical relation for the temperature-dependent shear modulus of the polymer glass on approaching "T" from below has been developed by Alessio Zaccone and Eugene Terentjev. Even though the shear modulus does not really drop to zero (it drops down to the much lower value of the rubber plateau), upon setting the shear modulus to zero in the Zaccone–Terentjev formula, an expression for "T" is obtained which recovers the Flory–Fox equation, and also shows that "T" is inversely proportional to the thermal expansion coefficient in the glass state. This procedure provides yet another operational protocol to define the "T" of polymer glasses by identifying it with the temperature at which the shear modulus drops by many orders of magnitude down to the rubbery plateau.


title: Glass transition

text: In ironing, a fabric is heated through this transition so that the polymer chains become mobile. The weight of the iron then imposes a preferred orientation. "T" can be significantly decreased by addition of plasticizers into the polymer matrix. Smaller molecules of plasticizer embed themselves between the polymer chains, increasing the spacing and free volume, and allowing them to move past one another even at lower temperatures. Addition of plasticizer can effectively take control over polymer chain dynamics and dominate the amounts of the associated free volume so that the increased mobility of polymer ends is not apparent. The addition of nonreactive side groups to a polymer can also make the chains stand off from one another, reducing "T". If a plastic with some desirable properties has a "T" that is too high, it can sometimes be combined with another in a copolymer or composite material with a "T" below the temperature of intended use. Note that some plastics are used at high temperatures, e.g., in automobile engines, and others at low temperatures.


title: Glass transition

text: In viscoelastic materials, the presence of liquid-like behavior depends on the properties of and so varies with rate of applied load, i.e., how quickly a force is applied. The silicone toy Silly Putty behaves quite differently depending on the time rate of applying a force: pull slowly and it flows, acting as a heavily viscous liquid; hit it with a hammer and it shatters, acting as a glass.


title: Glass transition

text: On cooling, rubber undergoes a "liquid-glass transition", which has also been called a "rubber-glass transition".


title: Glass transition

text: Molecular motion in condensed matter can be represented by a Fourier series whose physical interpretation consists of a superposition of longitudinal and transverse waves of atomic displacement with varying directions and wavelengths. In monatomic systems, these waves are called "density fluctuations". (In polyatomic systems, they may also include compositional fluctuations.)


title: Glass transition

text: Thus, thermal motion in liquids can be decomposed into elementary longitudinal vibrations (or acoustic phonons) while transverse vibrations (or shear waves) were originally described only in elastic solids exhibiting the highly ordered crystalline state of matter. In other words, simple liquids cannot support an applied force in the form of a shearing stress, and will yield mechanically via macroscopic plastic deformation (or viscous flow). Furthermore, the fact that a solid deforms locally while retaining its rigidity – while a liquid yields to macroscopic viscous flow in response to the application of an applied shearing force – is accepted by many as the mechanical distinction between the two.


title: Glass transition

text: The inadequacies of this conclusion, however, were pointed out by Frenkel in his revision of the kinetic theory of solids and the theory of elasticity in liquids. This revision follows directly from the continuous characteristic of the viscoelastic crossover from the liquid state into the solid one when the transition is not accompanied by crystallization—ergo the supercooled viscous liquid. Thus we see the intimate correlation between transverse acoustic phonons (or shear waves) and the onset of rigidity upon vitrification, as described by Bartenev in his mechanical description of the vitrification process.


title: Glass transition

text: This concept leads to defining the glass transition in terms of the vanishing or significant lowering of the low-frequency shear modulus, as shown quantitatively in the work of Zaccone and Terentjev on the example of polymer glass. In fact, the shoving model stipulates that the activation energy of the relaxation time is proportional to the high-frequency plateau shear modulus, a quantity that increases upon cooling thus explaining the ubiquitous non-Arrhenius temperature dependence of the relaxation time in glass-forming liquids.


title: Glass transition

text: The velocities of longitudinal acoustic phonons in condensed matter are directly responsible for the thermal conductivity that levels out temperature differentials between compressed and expanded volume elements. Kittel proposed that the behavior of glasses is interpreted in terms of an approximately constant "mean free path" for lattice phonons, and that the value of the mean free path is of the order of magnitude of the scale of disorder in the molecular structure of a liquid or solid. The thermal phonon mean free paths or relaxation lengths of a number of glass formers have been plotted versus the glass transition temperature, indicating a linear relationship between the two. This has suggested a new criterion for glass formation based on the value of the phonon mean free path.


title: Glass transition

text: It has often been suggested that heat transport in dielectric solids occurs through elastic vibrations of the lattice, and that this transport is limited by elastic scattering of acoustic phonons by lattice defects (e.g. randomly spaced vacancies).


title: Glass transition

text: These predictions were confirmed by experiments on commercial glasses and glass ceramics, where mean free paths were apparently limited by "internal boundary scattering" to length scales of . The relationship between these transverse waves and the mechanism of vitrification has been described by several authors who proposed that the onset of correlations between such phonons results in an orientational ordering or "freezing" of local shear stresses in glass-forming liquids, thus yielding the glass transition.


title: Glass transition

text: The influence of thermal phonons and their interaction with electronic structure is a topic that was appropriately introduced in a discussion of the resistance of liquid metals. Lindemann's theory of melting is referenced, and it is suggested that the drop in conductivity in going from the crystalline to the liquid state is due to the increased scattering of conduction electrons as a result of the increased amplitude of atomic vibration. Such theories of localization have been applied to transport in metallic glasses, where the mean free path of the electrons is very small (on the order of the interatomic spacing).


title: Glass transition

text: The formation of a non-crystalline form of a gold-silicon alloy by the method of splat quenching from the melt led to further considerations of the influence of electronic structure on glass forming ability, based on the properties of the metallic bond.


title: Glass transition

text: Other work indicates that the mobility of localized electrons is enhanced by the presence of dynamic phonon modes. One claim against such a model is that if chemical bonds are important, the nearly free electron models should not be applicable. However, if the model includes the buildup of a charge distribution between all pairs of atoms just like a chemical bond (e.g., silicon, when a band is just filled with electrons) then it should apply to solids.


title: Glass transition

text: Thus, if the electrical conductivity is low, the mean free path of the electrons is very short. The electrons will only be sensitive to the short-range order in the glass since they do not get a chance to scatter from atoms spaced at large distances. Since the short-range order is similar in glasses and crystals, the electronic energies should be similar in these two states. For alloys with lower resistivity and longer electronic mean free paths, the electrons could begin to sense that there is disorder in the glass, and this would raise their energies and destabilize the glass with respect to crystallization. Thus, the glass formation tendencies of certain alloys may therefore be due in part to the fact that the electron mean free paths are very short, so that only the short-range order is ever important for the energy of the electrons.


title: Glass transition

text: It has also been argued that glass formation in metallic systems is related to the "softness" of the interaction potential between unlike atoms. Some authors, emphasizing the strong similarities between the local structure of the glass and the corresponding crystal, suggest that chemical bonding helps to stabilize the amorphous structure.


title: Glass transition

text: Other authors have suggested that the electronic structure yields its influence on glass formation through the directional properties of bonds. Non-crystallinity is thus favored in elements with a large number of polymorphic forms and a high degree of bonding anisotropy. Crystallization becomes more unlikely as bonding anisotropy is increased from isotropic metallic to anisotropic metallic to covalent bonding, thus suggesting a relationship between the group number in the periodic table and the glass forming ability in elemental solids.


title: Shoaib Ibrahim

text: Shoaib Ibrahim (born 20 June 1987) is an Indian actor who works in Hindi television. He is known for playing Prem Bhardwaj in Colors TV's popular show "Sasural Simar Ka". In 2017 he participated in Star Plus's dance reality show "Nach Baliye 8".


title: Shoaib Ibrahim

text: Ibrahim began his television career as Karan Pratap on Imagine TV's "Rehna Hai Teri Palkon Ki Chhaon Mein" in 2009.


title: Shoaib Ibrahim

text: In 2011, Ibrahim was seen in a lead role as Prem Bharadwaj in "Sasural Simar Ka" on Colors TV. In 2013, he left and then got replaced by Dheeraj Dhoopar.


title: Shoaib Ibrahim

text: Following a three years long break, in 2017, Ibrahim resumed his TV journey and played dual roles of Abhimanyu and Aditya Singh Rathore on Sphere Origins's production "Koi Laut Ke Aaya Hai" via Star Plus opposite Surbhi Jyoti. In the same year, he participated in the dance reality show "Nach Baliye 8" on Star Plus along with his wife Dipika Kakar.


title: Shoaib Ibrahim

text: In March 2018, he participated in "Box Cricket League 3". He was next seen in Zee TV's "Jeet Gayi Toh Piya Morey" where he played the role of Varun Babbar opposite Yesha Rughani. From 2018 to 2019, Ibrahim starred in "Ishq Mein Marjawan" on Colors TV as Abhimanyu.


title: Shoaib Ibrahim

text: In January 2019, he made his debut into Bollywood industry with the movie "Battalion 609" as Kamraj Mishra.


title: Shoaib Ibrahim

text: After a gap of 3 years, he made a comeback in July 2022 with Star Bharat's "Ajooni" as Rajveer Singh Bagga.


title: Arm

text: In human anatomy, the arm refers to the upper limb in common usage, although academically the term specifically means the upper arm between the glenohumeral joint (shoulder joint) and the elbow joint. The distal part of the upper limb between the elbow and the radiocarpal joint (wrist joint) is known as the forearm or "lower" arm, and the extremity beyond the wrist is the hand.


title: Arm

text: By anatomical definitions, the bones, ligaments and skeletal muscles of the shoulder girdle, as well as the axilla between them, is considered parts of the upper limb, and thus also components of the arm. The Latin term "brachium", which serves as a root word for naming many anatomical structures, may refer to either the upper limb as a whole or to the upper arm on its own.


title: Arm

text: The humerus is one of the three long bones of the arm. It joins with the scapula at the shoulder joint and with the other long bones of the arm, the ulna and radius at the elbow joint. The elbow is a complex hinge joint between the end of the humerus and the ends of the radius and ulna.


title: Arm

text: The arm is divided by a fascial layer (known as lateral and medial intermuscular septa) separating the muscles into two "osteofascial compartments": the anterior and the posterior compartments of the arm. The fascia merges with the periosteum (outer bone layer) of the humerus.


title: Arm

text: The anterior compartment contains three muscles: biceps brachii, brachialis and coracobrachialis muscles. They are all innervated by the musculocutaneous nerve. The posterior compartment contains only the triceps brachii muscle, supplied by the radial nerve.


title: Arm

text: The musculocutaneous nerve, from C5, C6, C7, is the main supplier of muscles of the anterior compartment. It originates from the lateral cord of the brachial plexus of nerves. It pierces the coracobrachialis muscle and gives off branches to the muscle, as well as to brachialis and biceps brachii. It terminates as the anterior cutaneous nerve of the forearm.


title: Arm

text: The radial nerve, which is from the fifth cervical spinal nerve to the first thoracic spinal nerve, originates as the continuation of the posterior cord of the brachial plexus. This nerve enters the lower triangular space (an imaginary space bounded by, amongst others, the shaft of the humerus and the triceps brachii) of the arm and lies deep to the triceps brachii. Here it travels with the deep artery of the arm, which sits in the radial groove of the humerus. This fact is very important clinically as a fracture of the shaft of the bone here can cause lesions or even transections in the nerve.


title: Arm

text: The main artery in the arm is the brachial artery. This artery is a continuation of the axillary artery. The point at which the axillary becomes the brachial is distal to the lower border of teres major. The brachial artery gives off an unimportant branch, the deep artery of arm. This branching occurs just below the lower border of teres major.


title: Arm

text: The brachial artery continues to the cubital fossa in the anterior compartment of the arm. It travels in a plane between the biceps and triceps muscles, the same as the median nerve and basilic vein. It is accompanied by venae comitantes (accompanying veins). It gives branches to the muscles of the anterior compartment. The artery is in between the median nerve and the tendon of the biceps muscle in the cubital fossa. It then continues into the forearm.


title: Arm

text: The deep artery of the arm travels through the lower triangular space with the radial nerve. From here onwards it has an intimate relationship with the radial nerve. They are both found deep to the triceps muscle and are located on the spiral groove of the humerus. Therefore, fracture of the bone may not only lead to lesion of the radial nerve, but also haematoma of the internal structures of the arm. The artery then continues on to anastamose with the recurrent radial branch of the brachial artery, providing a diffuse blood supply for the elbow joint.


title: Arm

text: The veins of the arm carry blood from the extremities of the limb, as well as drain the arm itself. The two main veins are the basilic and the cephalic veins. There is a connecting vein between the two, the median cubital vein, which passes through the cubital fossa and is clinically important for venepuncture (withdrawing blood).


title: Arm

text: The basilic vein travels on the medial side of the arm and terminates at the level of the seventh rib.


title: Arm

text: The cephalic vein travels on the lateral side of the arm and terminates as the axillary vein. It passes through the deltopectoral triangle, a space between the deltoid and the pectoralis major muscles.


title: Arm

text: In Hindu, Buddhist and Egyptian iconography the symbol of the arm is used to illustrate the power of the sovereign. In Hindu tradition gods are depicted with several arms which carry specific symbols of their powers. It is believed that several arms depict omnipotence of gods. In popular culture Thakur did not have arms in the movie Sholay.


title: Arm

text: In West Africa, the Bambara use forearm to symbolize the spirit, which is a link between God and man.


title: Arm

text: In other animals, the term "arm" can also be used for homologous or analogous structures (such as one of the paired forelimbs of a four-legged animal or the arms of cephalopods, respectively). In anatomical usage, the term "arm" may sometimes refer specifically to the segment between the shoulder and the elbow, while the segment between the elbow and wrist is the forearm. However, in common, literary, and historical usage, "arm" refers to the entire upper limb from shoulder to wrist. This article uses the former definition; see upper limb for the wider definition.


title: Arm

text: In primates the arm is adapted for precise positioning of the hand and thus assist in the hand's manipulative tasks. The ball and socket shoulder joint allows for movement of the arms in a wide circular plane, while the structure of the two forearm bones which can rotate around each other allows for additional range of motion at that level.


title: United States five-dollar bill

text: The United States five-dollar bill ($5) is a denomination of United States currency. The current $5 bill features a portrait of Abraham Lincoln, the 16th U.S. president (1861-1865), on the front and the Lincoln Memorial on the back. All $5 bills issued today are Federal Reserve Notes.


title: United States five-dollar bill

text: The $5 bill is sometimes nicknamed a "fin". The term has German/Yiddish roots and is remotely related to the English "five", but it is far less common today than it was in the late 19th and early 20th centuries.


title: United States five-dollar bill

text: , the average life of a $5 bill in circulation is 4.7 years before it is replaced due to wear. Approximately 6% of all paper currency produced by the U.S. Treasury's Bureau of Engraving and Printing in 2009 were $5 bills.


title: United States five-dollar bill

text: The redesigned $5 bill was unveiled on September 20, 2007, and was issued on March 13, 2008 during a ceremony at President Lincoln's Cottage.


title: United States five-dollar bill

text: New and enhanced security features make it easier to check the new $5 bill and more difficult for potential counterfeiters to reproduce. The redesigned $5 bill has:


title: United States five-dollar bill

text: The new $5 bills remain the same size and use the same—but enhanced—portraits and historical images. The most noticeable difference is the light-purple coloring of the center of the bill, which blends into gray near the edges.


title: United States five-dollar bill

text: Similar to the recently redesigned $10, $20, $50, and $100 bills, the new $5 bill features an American symbol of freedom printed in the background: The Great Seal of the United States, featuring an eagle and shield, is printed in purple to the right of the portrait and an arc of purple stars surround both it and the portrait.


title: United States five-dollar bill

text: When the Lincoln Memorial was constructed the names of 48 states were engraved on it. The picture of the Lincoln Memorial on the $5 bill only contains the names of 26 states. These are the 26 states that can be seen on the front side of the Lincoln memorial which is what is pictured on the $5 bill.


title: United States five-dollar bill

text: On the back of the bill, a larger, purple numeral "5" appears in the lower right corner to help those with visual impairments to distinguish the denomination. This large "5" also includes the words "USA FIVE" in tiny white letters.


title: United States five-dollar bill

text: The oval borders around President Lincoln's portrait on the front, and the Lincoln Memorial vignette on the back have been removed. Both engravings have been enhanced.


title: United States five-dollar bill

text: On April 20, 2016, Treasury Secretary Jacob Lew announced that the $5, $10, and $20 would all undergo redesign prior to 2020. The changes would add new features to combat counterfeiting and make them easier for blind citizens to distinguish. Lew said that while Lincoln would remain on the obverse, the reverse would be redesigned to depict various historical events that had occurred at the Lincoln Memorial. Among the planned designs are images from Martin Luther King Jr. giving his 1963 speech "I Have a Dream" and the 1939 concert by opera singer Marian Anderson. , the Treasury has continued work on the $20 bill; the redesigns of the $5 and $10 were not mentioned.


title: Polecat

text: Polecat is a common name for several mustelid species in the order Carnivora and subfamilies Ictonychinae and Mustelinae. Polecats do not form a single taxonomic rank (i.e. clade). The name is applied to several species with broad similarities to European polecats, the only polecat species native to the British Isles, such as having a dark mask-like marking across the face.


title: Polecat

text: In the United States, the term "polecat" is sometimes applied to the black-footed ferret, a native member of the Mustelinae. In Southern United States dialect, the term "polecat" is sometimes used as a colloquial nickname for the skunk, which is only distantly related to mustelids.


title: Polecat

text: Despite their common name, polecats are more closely related to dogs than cats, which is why they are placed in the suborder Caniformia.


title: Polecat

text: According to the most recent taxonomic scheme proposing eight subfamilies within Mustelidae, polecats are classified as:


title: Hydroxyapatite

text: Hydroxyapatite, also called hydroxylapatite (HA), is a naturally occurring mineral form of calcium apatite with the formula Ca(PO)(OH), but it is usually written Ca(PO)(OH) to denote that the crystal unit cell comprises two entities. Hydroxyapatite is the hydroxyl endmember of the complex apatite group. The OH ion can be replaced by fluoride, chloride or carbonate, producing fluorapatite or chlorapatite. It crystallizes in the hexagonal crystal system. Pure hydroxyapatite powder is white. Naturally occurring apatites can, however, also have brown, yellow, or green colorations, comparable to the discolorations of dental fluorosis.


title: Hydroxyapatite

text: Up to 50% by volume and 70% by weight of human bone is a modified form of hydroxyapatite, known as bone mineral. Carbonated calcium-deficient hydroxyapatite is the main mineral of which dental enamel and dentin are composed. Hydroxyapatite crystals are also found in pathological calcifications such as those found in breast tumors, as well as calcifications within the pineal gland (and other structures of the brain) known as corpora arenacea or "brain sand".


title: Hydroxyapatite

text: Hydroxyapatite can be synthesized via several methods, such as wet chemical deposition, biomimetic deposition, sol-gel route (wet-chemical precipitation) or electrodeposition. The hydroxyapatite nanocrystal suspension can be prepared by a wet chemical precipitation reaction following the reaction equation below:


title: Hydroxyapatite

text: The ability to synthetically replicate hydroxyapatite has invaluable clinical implications, especially in dentistry. Each technique yields hydroxyapatite crystals of varied characteristics, such as size and shape. These variations have a marked effect on the biological and mechanical properties of the compound, and therefore these hydroxyapatite products have different clinical uses.


title: Hydroxyapatite

text: Calcium-deficient (non-stochiometric) hydroxyapatite, Ca(PO)(HPO)(OH) (where "x" is between 0 and 1) has a Ca/P ratio between 1.67 and 1.5. The Ca/P ratio is often used in the discussion of calcium phosphate phases. Stoichiometric apatite Ca(PO)(OH) has a Ca/P ratio of 10:6 normally expressed as 1.67. The non-stoichiometric phases have the hydroxyapatite structure with cation vacancies (Ca) and anion (OH) vacancies. The sites occupied solely by phosphate anions in stoichiometric hydroxyapatite, are occupied by phosphate or hydrogen phosphate, HPO, anions.


title: Hydroxyapatite

text: Preparation of these calcium-deficient phases can be prepared by precipitation from a mixture of calcium nitrate and diammonium phosphate with the desired Ca/P ratio, for example, to make a sample with a Ca/P ratio of 1.6:


title: Hydroxyapatite

text: Sintering these non-stoichiometric phases forms a solid phase which is an intimate mixture of tricalcium phosphate and hydroxyapatite, termed biphasic calcium phosphate:


title: Hydroxyapatite

text: The clubbing appendages of the "Odontodactylus scyllarus" (peacock mantis shrimp) are made of an extremely dense form of the mineral which has a higher specific strength; this has led to its investigation for potential synthesis and engineering use. Their dactyl appendages have excellent impact resistance due to the impact region being composed of mainly crystalline hydroxyapatite, which offers significant hardness. A periodic layer underneath the impact layer composed of hydroxyapatite with lower calcium and phosphorus content (thus resulting in a much lower modulus) inhibits crack growth by forcing new cracks to change directions. This periodic layer also reduces the energy transferred across both layers due to the large difference in modulus, even reflecting some of the incident energy.


title: Hydroxyapatite

text: Hydroxyapatite is present in bone and teeth; bone is made primarily of HA crystals interspersed in a collagen matrix—65 to 70% of the mass of bone is HA. Similarly HA is 70 to 80% of the mass of dentin and enamel in teeth. In enamel, the matrix for HA is formed by amelogenins and enamelins instead of collagen.


title: Hydroxyapatite

text: Hydroxyapatite deposits in tendons around joints results in the medical condition calcific tendinitis.


title: Hydroxyapatite

text: Remineralisation of tooth enamel involves the reintroduction of mineral ions into demineralised enamel. Hydroxyapatite is the main mineral component of enamel in teeth. During demineralisation, calcium and phosphorus ions are drawn out from the hydroxyapatite. The mineral ions introduced during remineralisation restore the structure of the hydroxyapatite crystals. If fluoride ions are present during the remineralisation, through water fluoridation or the use of fluoride-containing toothpaste, the stronger and more acid-resistant fluorapatite crystals are formed instead of the hydroxyapatite crystals.


title: Hydroxyapatite

text: , the use of hydroxyapatite, or its synthetically manufactured form, nano-hydroxyapatite, is not yet common practice. Some studies suggest it is useful in counteracting dentine hypersensitivity, preventing sensitivity after teeth bleaching procedures and caries prevention. Avian eggshell hydroxyapatite can be a viable filler material in bone regeneration procedures in oral surgery.


title: Hydroxyapatite

text: Nano-hydroxyapatite possesses bioactive components which can prompt the mineralisation process of teeth, remedying hypersensitivity. Hypersensitivity of teeth is thought to be regulated by fluid within dentinal tubules. The movement of this fluid as a result of different stimuli is said to excite receptor cells in the pulp and trigger sensations of pain. The physical properties of the nano-hydroxyapatite can penetrate and seal the tubules, stopping the circulation of the fluid and therefore the sensations of pain from stimuli. Nano-hydroxyapatite would be preferred as it parallels the natural process of surface remineralisation.


title: Hydroxyapatite

text: In comparison to alternative treatments for dentine hypersensitivity relief nano-hydroxyapatite containing treatment has been shown to perform better clinically. Nano-hydroxyapatite was proven to be better than other treatments at reducing sensitivity against evaporative stimuli, such as an air blast, and tactile stimuli, such as tapping the tooth with a dental instrument. However, no difference was seen between nano-hydroxyapatite and other treatments for cold stimuli. Hydroxyapatite has shown significant medium and long-term desensitizing effects on dentine hypersensitivity using evaporative stimuli and the visual analogue scale (alongside potassium nitrate, arginine, glutaraldehyde with hydroxyethyl methacrylate, hydroxyapatite, adhesive systems, glass ionomer cements and laser).


title: Hydroxyapatite

text: Teeth bleaching agents release reactive oxygen species which can degrade enamel. To prevent this, nano-hydroxyapatite can be added to the bleaching solution to reduce the impact of the bleaching agent by blocking pores within the enamel. This reduces sensitivity after the bleaching process.


title: Hydroxyapatite

text: Nano-hydroxyapatite possesses a remineralising effect on teeth and can be used to prevent damage from carious attacks. In the event of an acid attack by cariogenic bacteria, nano-hydroxyapatite particles can infiltrate pores on the tooth surface to form a protective layer. Furthermore, nano-hydroxyapatite may have the capacity to reverse damage from carious assaults by either directly replacing deteriorated surface minerals or acting as a binding agent for lost ions.


title: Hydroxyapatite

text: In the future, there are possibilities for using nano-hydroxyapatite for tissue engineering and repair. The main and most advantageous feature of nano-hydroxyapatite is its biocompatibility. It is chemically similar to naturally occurring hydroxyapatite and can mimic the structure and biological function of the structures found in the resident extracellular matrix. Therefore, it can be used as a scaffold for engineering tissues such as bone and cementum. It may be used to restore cleft lips and palates and refine existing practices such as preservation of alveolar bone after extraction for better implant placement.


title: Hydroxyapatite

text: Hydroxyapatite is widely used within dentistry and oral and maxillofacial surgery, due to its chemical similarity to hard tissue.


title: Hydroxyapatite

text: In some toothpaste hydroxyapatite can be found in the form of nanocrystals (as these are easily dissolved). In recent years, hydroxyapatite nanocrystals (nHA) have been used in toothpaste to combat dental hypersensitivity. They aid in the repair and remineralisation of the enamel, thus helping to prevent tooth sensitivity. Tooth enamel can become demineralised due to various factors, including acidic erosion and dental caries. If left untreated this can lead to the exposure of dentin and subsequent exposure of the dental pulp. In various studies the use of nano hydroxyapatite in toothpaste showed positive results in aiding the remineralisation of dental enamel.


title: Hydroxyapatite

text: Synthetic hydroxyapatite (SHA) is proven to provide successful outcomes in alveolar socket preservation. Socket grafting using synthetic hydroxyapatite can result in successful bone regeneration.


title: Hydroxyapatite

text: The European Commission's Scientific Committee on Consumer Safety (SCCS) issued an official opinion in 2021, where it considered whether the nanomaterial hydroxyapatite was safe when used in leave-on and rinse-off dermal and oral cosmetic products, taking into account reasonably foreseeable exposure conditions. It stated:


title: Hydroxyapatite

text: The mechanism of hydroxyapatite chromatography is complicated and has been described as "mixed-mode". It involves ionic interactions between positively charged groups on a biomolecule (often a protein) and the phosphate groups in hydroxyapatite, and metal chelation between hydroxyapatite calcium ions and negatively charged phosphate and/or carboxyl groups on the biomolecule. It may be difficult to predict the effectiveness of hydroxyapatite chromatography based on physical and chemical properties of the desired protein to be purified. For elution, a buffer with increasing phosphate and/or neutral salt concentration is typically used.


title: Hydroxyapatite

text: In archaeology, hydroxyapatite from human and animal remains can be analysed to reconstruct ancient diets, migrations and paleoclimate. The mineral fractions of bone and teeth act as a reservoir of trace elements, including carbon, oxygen and strontium. Stable isotope analysis of human and faunal hydroxyapatite can be used to indicate whether a diet was predominantly terrestrial or marine in nature (carbon, strontium); the geographical origin and migratory habits of an animal or human (oxygen, strontium) and to reconstruct past temperatures and climate shifts (oxygen). Post-depositional alteration of bone can contribute to the degradation of bone collagen, the protein required for stable isotope analysis.


title: Hydroxyapatite

text: Hydroxyapatite is a potential adsorbent for the defluoridation of drinking water, as it forms fluorapatite in a three step process. Hydroxyapatite removes F from the water to replace OH forming fluorapatite. However, during the defluoridation process the hydroxyapatite dissolves, and increases the pH and phosphate ion concentration which makes the defluoridated water unfit for drinking. Recently, a ″calcium amended-hydroxyapatite″ defluoridation technique was suggested to overcome the phosphate leaching from hydroxyapatite. This technique can also affect fluorosis reversal by providing calcium-enriched alkaline drinking water to fluorosis affected areas.


title: Abortion in the United Kingdom

text: Abortion in the United Kingdom is "de facto" available through the "Abortion Act 1967" in Great Britain, and the "". The "Abortion Act 1967" provides a legal defence for doctors to perform abortions, though abortion also remains a criminal offence under the "Offences Against the Person Act 1861". Although a number of abortions did take place before the 1967 Act, there have been around 10 million abortions in the United Kingdom. Around 200,000 abortions are carried out in England and Wales each year and just under 14,000 in Scotland; the most common reason cited under the ICD-10 classification system for around 98% of all abortions is "risk to woman's mental health."


title: Abortion in the United Kingdom

text: The third ground is typically interpreted liberally with regards to mental health to create a "de facto" elective abortion service.


title: Abortion in the United Kingdom

text: In Northern Ireland, abortion is permitted on similar grounds although the law also permits abortion in the first 12 weeks of a pregnancy for any reason, as is also the case in the Republic of Ireland.


title: Abortion in the United Kingdom

text: Under the UK's devolution settlements, abortion policy is devolved to the Scottish Parliament and the Northern Ireland Assembly but not to the Welsh Parliament (Senedd). Abortion was previously highly restricted in Northern Ireland although it was permitted in limited cases. In 2019, during a time when the Assembly was not operating, the UK Parliament repealed most restrictions on abortion in Northern Ireland; the current Regulations were subsequently introduced by Parliament in 2020.


title: Abortion in the United Kingdom

text: Abortions which are carried out for grounds outside those permitted in law (e.g. in most cases after the 24-week term limit, or where appropriate consent has not been given) continue to be unlawful in each jurisdiction of the UK – under the Offences against the Person Act 1861 in England and Wales, Scottish common law, and the . The Infant Life (Preservation) Act 1929 and the Criminal Justice Act (Northern Ireland) 1945 also outlaw child destruction in cases outside the grounds permitted in abortion law.


title: Abortion in the United Kingdom

text: Debates and practices relating to abortion and the beginning of human life are recorded in Roman literature and would also have been known in Celtic culture, although written Celtic texts were not available until around the 4th Century AD. Several studies of the burials of children who died before or near birth in Roman Britain have been made. An early Christian understanding of abortion and infanticide, as outlined in the 1st Century AD "Didache" and similar writings, would have been known in the early British Church which experienced greater religious freedom following Constantine's Edict of Milan in 313 AD, and also in the early Irish Church after its establishment around 432 AD. Alongside the growing influence of the Church and its teachings in Roman society, a more significant sense of value was associated with the life (and death) of infant and neo-natal children. One study of that time notes that "the presence of neo-natal burials given the same burial rites as adults ... is a pointer to identification of the cemetery as Christian" and that such burials were rare before the 4th century.


title: Abortion in the United Kingdom

text: Abortion was mainly dealt with by the ecclesiastical courts under the laws of the Roman Catholic Church until their abolition during the Reformation. Ecclesiastical courts dealt mainly with the issue due to problems of evidence in such cases; the courts had wider evidential rules and more discretion regarding sentencing. A number of cases such as the "Twinslayers Case" (1327) were heard in the secular courts. Later, under Scottish common law, abortion was defined as a criminal offence unless performed for "reputable medical reasons", a definition sufficiently broad as to essentially preclude prosecution.


title: Abortion in the United Kingdom

text: The law on abortion started to be codified in legislation and dealt with in the courts of the state under sections 1 and 2 of Lord Ellenborough's Act (1803). The offences created by this statute were replaced by section 13 of the Offences Against the Person Act 1828. Under section 1 of the 1803 Act and the first offence created by section 13 of the 1828 Act, the crime of abortion was subject, in cases where the woman was proved to have been quick with child, to the death penalty or penal transportation for life. Under section 2 of the 1803 Act and the second offence created by section 13 of the 1828 Act (all other cases), the penalty was transportation for 14 years.


title: Abortion in the United Kingdom

text: Section 13 of the 1828 Act was replaced by section 6 of the Offences Against the Person Act 1837. This section made no distinction between women who were quick with child and those who were not; it also eliminated the death penalty as a possible punishment.


title: Abortion in the United Kingdom

text: Transportation was abolished by the Penal Servitude Act 1857, which replaced it with penal servitude. Section 6 of the 1837 Act was replaced by section 58 of the Offences against the Person Act 1861 which continues to be the main legislation for prosecuting personal injury in the courts of England and Wales, and was adopted elsewhere in the British Empire. In addition, section 59 of that Act created a new preparatory offence of procuring drugs or instruments with intent to procure abortion.


title: Abortion in the United Kingdom

text: From 1870, there was a steady decline in fertility, linked not to a rise in the use of artificial contraception but to more traditional methods such as withdrawal and abstinence. This was linked to changes in the perception of the relative costs of childrearing. Abortifacents were discreetly advertised for women with unwanted pregnancies who sought abortions and there was a considerable body of folklore about methods of inducing miscarriages. Amongst working-class women, violent purgatives were popular, including pennyroyal, aloes and turpentine. Other methods to induce miscarriage were very hot baths and gin, extreme exertion, a controlled fall down a flight of stairs, or veterinary medicines. So-called 'backstreet' abortionists were relatively common, although their efforts could be fatal. Estimates of the number of illegal abortions varied widely; by one estimate, 100,000 women made efforts to procure an abortion in 1914, usually by drugs.


title: Abortion in the United Kingdom

text: The criminality of abortion in England and Wales was reaffirmed in 1929, when the Infant Life (Preservation) Act was passed. The Act criminalised the deliberate destruction of a child "capable of being born alive". This was to close a lacuna in the law, identified by Lord Darling, which allowed for infants to be killed during birth, which would mean that the perpetrator could neither be prosecuted for abortion or murder. The Act included the presumption that all children in utero over 28 weeks of gestation were capable of being born alive. Where the life of child in utero was ended before this gestation, evidence was presented and considered to determine whether or not they were capable of being born alive.


title: Abortion in the United Kingdom

text: In 1938, the decision in "R v. Bourne" allowed for further considerations to be taken into account. This case related to an abortion performed on a girl who had been raped, and extended the defence to abortion to include "mental and physical wreck" (Lord Justice McNaghtan). The gynaecologist concerned, Aleck Bourne, later became a founder member of the anti-abortion group, the Society for the Protection of Unborn Children (SPUC) in 1966.


title: Abortion in the United Kingdom

text: In 1939, the Inter-Departmental Committee on Abortion, established by the Home Office and Ministry of Health, recommended a change to abortion laws but the intervention of World War II meant that all plans were shelved. Post-war, after decades of stasis, certain high-profile tragedies, including disability in unborn children caused by the thalidomide drug, and social changes brought the issue of abortion back into the political arena.


title: Abortion in the United Kingdom

text: Westminster’s responsibility for criminal justice and health policy, including around abortion, on the island of Ireland was transferred to the Northern Ireland Parliament (on its formation in 1921) and the Parliament of the Irish Free State (formed in December 1922). Both legislatures took an essentially conservative position, viewing abortion as an offence against the person, or an offence of child destruction, in line with existing legislation in England and Wales.


title: Abortion in the United Kingdom

text: The Abortion Act 1967 sought to clarify the law in Britain. Introduced by David Steel and subject to heated debate, it allowed for legal abortion on a number of grounds, with the added protection of free provision through the National Health Service. The Act was passed on 27 October 1967 and came into effect on 27 April 1968.


title: Abortion in the United Kingdom

text: Before the Human Fertilisation and Embryology Act 1990 amended the Act, the Infant Life (Preservation) Act 1929 acted as a buffer to the Abortion Act 1967. This meant that abortions could not be carried out if the child was "capable of being born alive". There was therefore no statutory limit put into the Abortion Act 1967, the limit being that which the courts decided as the time at which a child could be born alive. The "C v S" case in 1987 confirmed that, at that time, between 19 and 22 weeks a foetus was not capable of being born alive. The 1967 Act required that the procedure must be certified by two doctors before being performed.


title: Abortion in the United Kingdom

text: During each Parliament, several private member's bills are generally introduced to seek to amend the law in relation to abortion. In the years following a supportive report in favour of the 1967 Act by the Lane Committee in 1974, Members of Parliament introduced four bills which have resulted in substantive debate in the House of Commons (votes are indicated in brackets with ayes followed by noes):


title: Abortion in the United Kingdom

text: In addition, in 1990, members voted on several proposed amendments to clause 34 of the "Human Fertilisation and Embryology Bill" relating to the termination of pregnancy.)


title: Abortion in the United Kingdom

text: The Human Fertilisation and Embryology Act 1990, as enacted, lowered the term limit from 28 to 24 weeks for abortion in cases of 'mental or physical injury' on the ground that medical technology had advanced sufficiently (since 1967) to justify the change but removed restrictions for late abortions in cases of risk to life, grave physical and mental injury to the woman, and the disability in the unborn child (by separating the legal effect of the Infant Life (Preservation) Act 1929 from the Abortion Act 1967).


title: Abortion in the United Kingdom

text: When a further Human Fertilisation and Embryology Bill (now enacted) was considered by Parliament in 2008, several votes were held on the term limit in Britain, as follows:


title: Abortion in the United Kingdom

text: Pro-choice groups strongly opposed any attempts to restrict abortion in the 2008 parliamentary debates and votes. A number of pro-choice amendments were proposed by the Labour MPs Diane Abbott, Katy Clark and John McDonnell, including "NC30 Amendment of the Abortion Act 1967: Application to Northern Ireland". However, it was reported that the Labour government at the time asked MPs not to table these amendments (at least until third reading) and then used parliamentary mechanisms in order to prevent a vote; the government was, at the time, seeking to devolve policing and justice powers to the Northern Ireland Assembly (which had previously voted to oppose the extension of the 1967 Act).


title: Abortion in the United Kingdom

text: In 2017, the "Reproductive Health (Access to Terminations) Bill" was introduced by Labour Diana Johnson MP with the aim of repealing criminal law on abortion in England and Wales. However, with the call for a general election, the bill fell and no further action was taken.


title: Abortion in the United Kingdom

text: Minor amendments to the Abortion Act 1967 have been introduced through government legislation, the most recent being the allowance of abortion consultations through telemedicine in the Health and Care Act 2022.


title: Abortion in the United Kingdom

text: Health, social care and criminal justice policy was devolved to the Northern Ireland Parliament at the time of the Abortion Act 1967's passage at Westminster and the Parliament did not introduce abortion legislation before its suspension in 1972. Statute law was maintained unchanged under Conservative and Labour direct rule administrations and the first Northern Ireland Assembly in 1973-1974 although the law was interpreted through case law in local courts (during the 1990s) to also allow for the grounds of "a risk of real and serious adverse effect on ... [the] physical or mental health [of the woman] is either long term or permanent". From 1983 onwards, the Constitution of Ireland, covering the Republic with a territorial claim on Northern Ireland until 1998, acknowledged "the right to life of the unborn and, with due regard to the equal right to life of the mother" and "guaranteed in its laws to respect, and, as far as practicable, by its laws to defend and vindicate that right."


title: Abortion in the United Kingdom

text: The new Northern Ireland Assembly, formed in 1998 following the Good Friday Agreement, voted in June 2000 to oppose the extension of the Abortion Act 1967 to Northern Ireland; the motion was proposed by the Democratic Unionist Party (DUP) and supported by the Social Democratic and Labour Party (SDLP) which was, at the time, opposed to abortion but also emphasised an understanding of the social, economic and personal circumstances that gave rise to women choosing the option of an abortion. While health policy had been devolved again to Northern Ireland in December 1999, on the formation of the first Northern Ireland Executive, criminal law (including in relation to abortion) continued to be reserved to Parliament at Westminster until the devolution of policing and justice powers in May 2010.


title: Abortion in the United Kingdom

text: Political debate around abortion issues was renewed following the opening of a private abortion clinic in Belfast in 2012, the Protection of Life During Pregnancy Act 2013 in the Republic, and the widespread discussion of a case of fatal foetal abnormality; several debates took place in the Northern Ireland Assembly and its members, in line with party policy and/or personal conscience, decided not to proceed with changes in the law. An amendment by DUP MLA Jim Wells to "restrict lawful abortions to NHS premises, except in cases of urgency when access to NHS premises is not possible and where no fee is paid" was unsuccessful. Later, as Health Minister, Jim Wells opposed abortion in cases of rape as the unborn child would be "punished for what has happened by having their life terminated" although he acknowledged that this would be "a tragic and difficult situation".


title: Abortion in the United Kingdom

text: Justice Minister David Ford (a member of the Alliance Party) issued a public consultation on amending the criminal law on abortion, which opened in October 2014 and closed in January 2015. However, Ford also wrote that "it is not a debate on the wider issues of abortion law – issues often labelled as 'pro-choice' and 'pro-life'". The Sinn Féin deputy First Minister, Martin McGuinness, had initially stated his party's opposition to abortion and noted that the party had "resisted any attempt to bring the British 1967 Abortion Act to the North." At its 2015 annual conference, Sinn Féin adopted a policy of allowing abortion under certain circumstances such as fatal foetal abnormality; this was superseded by a newer and more liberal policy adopted at its 2018 conference.


title: Abortion in the United Kingdom

text: In February 2016, during debates on the "Justice (No.2) Bill", the Assembly considered and debated an amendment to allow for abortion in cases of pregnancies caused by sexual crime (which was rejected by 64 notes to 32 ayes), and an amendment to allow for abortion in cases of fatal foetal abnormality (which was rejected by 59 noes to 40 ayes) . Sinn Féin and the Green Party voted in favour of both proposals whereas the DUP and the SDLP supported the existing law and members of the Ulster Unionist Party (UUP) and Alliance Party voted on conscience. The "Abortion (Fatal Foetal Abnormality) Bill" was introduced by David Ford, as a backbench MLA, in December 2016 but fell on the suspension of the Assembly in January 2017.


title: Abortion in the United Kingdom

text: In the 2017 UK general election, the Labour Party manifesto under the leadership of Jeremy Corbyn MP stated: "Labour will continue to ensure a woman’s right to choose a safe, legal abortion – and we will work with the Assembly to extend that right to women in Northern Ireland." The election resulted in a confidence and supply agreement between the Conservative Party and the (DUP). The Conservative Government, in June 2017, made a commitment to provide free abortion services in England for women from Northern Ireland due to pressure from Conservative MPs. The Labour Party commitment was, in effect, delivered through , which repealed the Offences against the Person Act 1861 (sections 58 and 59) in October 2019. The political context was also changed by legal challenges, the repeal of the Eighth Amendment in the Republic in 2018 (supported by Sinn Féin), and the SDLP's decision to consider abortion as a matter of conscience.


title: Abortion in the United Kingdom

text: Shortly after the introduction of the Abortion (Northern Ireland) Regulations 2020, the newly restored Northern Ireland Assembly voted – with 46 members in favour and 40 against – to reject "the imposition of abortion legislation that extends to all non-fatal disabilities, including Down's syndrome." Following this vote, the "Severe Fetal Impairment Abortion (Amendment) Bill" – to remove the grounds for abortion for non-fatal disabilities – was introduced by DUP MLA Paul Givan in February 2021. It reached its consideration stage in December 2021 but MLAs decided – by 45 votes to 43 – against the main proposal in the Bill at that stage.


title: Abortion in the United Kingdom

text: The main legislation on abortion in England, Scotland and Wales is the Abortion Act 1967, as amended by the Human Fertilisation and Embryology Act 1990. In Great Britain, abortion is generally allowed for socio-economic reasons during the first 24 weeks of the pregnancy (a later term limit than most other countries in Europe), and after this point for medical reasons.


title: Abortion in the United Kingdom

text: The Offences against the Person Act 1861, in England and Wales, prohibits administering drugs or using instruments to procure an abortion and procuring drugs or other items to cause an abortion although subsequent law has provided for a range of grounds which allow abortion to be widely available.


title: Abortion in the United Kingdom

text: The Infant Life (Preservation) Act 1929 amended the law in England and Wales to create the offence of child destruction – in cases where any person "who, with intent to destroy the life of a child capable of being born alive, by any wilful act causes a child to die before it has an existence independent of its mother". For the purposes of this Act, a child whose mother has been pregnant for 28 weeks is deemed "capable of being born alive". The 1929 Act also provides a defence where it is proved that causing the death of the child was "done in good faith for the purpose only of preserving the life of the mother."


title: Abortion in the United Kingdom

text: The Abortion Act 1967 originally permitted abortion "by a registered medical practitioner if two registered medical practitioners are of the opinion, formed in good faith" on the following grounds:


title: Abortion in the United Kingdom

text: The Act came into operation in 1968, and originally applied a term limit of 28 weeks, in line with the Infant Life Preservation Act. It was subsequently amended by the Human Fertilisation and Embryology Act 1990, to allow for the following grounds:


title: Abortion in the United Kingdom

text: The amendment therefore allowed for a reduction in the term limit to 24 weeks for Ground C and Ground D with the law changing to reflect advances in technology to enable premature children to be born alive earlier in a pregnancy. However, no term limit was applied to other grounds and abortion was permitted throughout the pregnancy in these cases. The changes took effect in April 1991.


title: Abortion in the United Kingdom

text: Abortion law was not devolved to the National Assembly for Wales under Government of Wales Act 1998 and was specifically reserved to the UK Parliament via the Government of Wales Act 2006.


title: Abortion in the United Kingdom

text: Abortion became an offence in Scotland with the passing of the Abortion Act 1967 and refers to "any rule of law relating to the procurement of abortion". Prior to 1967, there was no offence of abortion in Scotland; however, if harm occurred consequent to an abortion, various offences could have applied with abortion forming part of the description of the elements forming the offence on the petition or indictment presented to a court.


title: Abortion in the United Kingdom

text: The Scotland Act 1998, which established the Scottish Parliament, reserved abortion law to the UK Parliament but it was subsequently devolved through the Scotland Act 2016. The Abortion Act 1967 remains in place.


title: Abortion in the United Kingdom

text: Section 58 of the Offences against the Person Act 1861 reads as follows and prohibits administering drugs or using instruments to cause a miscarriage:


title: Abortion in the United Kingdom

text: Section 59 of that Act reads as follows and prohibits the procurement of drugs or other items to cause a miscarriage:


title: Abortion in the United Kingdom

text: A death of a person in being which is caused by an unlawful attempt to procure an abortion, is at least manslaughter.


title: Abortion in the United Kingdom

text: Between 1993 and 1999, a series of court cases had interpreted the law as also allowing for abortion in cases where, for the pregnant woman, "there is a risk of real and serious adverse effect on her physical or mental health, which is either long term or permanent".


title: Abortion in the United Kingdom

text: In "Northern Ireland Health and Social Services Board v A and Others" [1994] NIJB 1, Lord Justice MacDermott said that he was "satisfied that the statutory phrase, 'for the purpose only of preserving the life of the mother' does not relate only to some life-threatening situation. Life in this context means that physical or mental health or well-being of the mother and the doctor's act is lawful where the continuance of the pregnancy would adversely affect the mental or physical health of the mother. The adverse effect must however be a real and serious one and there will always be a question of fact and degree whether the perceived effect of non-termination is sufficiently grave to warrant terminating the unborn child."


title: Abortion in the United Kingdom

text: In "Western Health and Social Services Board v CMB and the Official Solicitor" (1995, unreported), Mr Justice Pringle stated that "the adverse effect must be permanent or long-term and cannot be short term ... in most cases the adverse effect would need to be a probable risk of non-termination but a possible risk might be sufficient if the imminent death of the mother was a risk in question".


title: Abortion in the United Kingdom

text: In "Family Planning Association of Northern Ireland v Minister for Health, Social Services and Public Safety" (October 2004), Lord Justice Nicholson stated that "it is unlawful to procure a miscarriage where the foetus is abnormal but viable, unless there is a risk that the mother may die or is likely to suffer long-term harm, which is serious, to her physical or mental health". In the same case, Lord Justice Sheil stated that "termination of a pregnancy based solely on abnormality of the foetus is unlawful and cannot lawfully be carried out in this jurisdiction".


title: Abortion in the United Kingdom

text: In November 2015, Lord Justice Horner made a declaration of incompatibility under the Human Rights Act 1998 to the effect that Northern Ireland's law on abortion (specifically its lack of provision in cases of fatal foetal abnormality or where the pregnancy is the result of rape or incest) could not be interpreted in a manner consistent with Article 8 of the European Convention on Human Rights i.e. a right to respect for his private and family life, his home and his correspondence; the convention also protects a right to life in Article 2. In June 2017, the declaration of incompatibility was quashed by the Court of Appeal on the grounds that "a broad margin of appreciation must be accorded to the state" and "a fair balance has been struck by the law as it presently stands until the legislature decides otherwise". In June 2018, the Supreme Court of the United Kingdom held that the law of Northern Ireland was incompatible with the right to respect for private and family life, insofar as the law prohibited abortion in cases of rape, incest and fatal foetal abnormality. However, the court did not restore the declaration of incompatibility as it also held that the claimant did not have standing to bring the proceedings and accordingly the court had no jurisdiction to make a declaration of incompatibility reflect its view on the compatibility issues. The judgments of the Supreme Court acknowledged that the court lacked jurisdiction to issue a declaration of incompatibility but included a non-binding opinion that an incompatibility existed, and that a future case in which the applicant had the necessary standing would be likely to succeed. It also urged the authorities "responsible for ensuring the compatibility of Northern Ireland law with the Convention rights" to "recognise and take account of these conclusions ... by considering whether and how to amend the law".


title: Abortion in the United Kingdom

text: The law on abortion in Northern Ireland was changed by Parliament during a suspension of the Northern Ireland Executive, which took place between 2017 and 2020. Recommendations to liberalise abortion law in Northern Ireland were published in February 2018 by the United Nations Committee on the Elimination of Discrimination against Women (CEDAW) in the report of its Inquiry concerning the United Kingdom (under Article 8 of the Optional Protocol to the Convention on the Elimination of All Forms of Discrimination against Women).


title: Abortion in the United Kingdom

text: The Northern Ireland (Executive Formation etc) Act 2019, enacted on 24 July 2019, extended the deadline for the restoration of the Executive to 21 October 2019. Under a private member's amendment introduced by Stella Creasy MP, if an Executive were not restored by that date, the Act would:


title: Abortion in the United Kingdom

text: On 21 October 2019, as a result of the Executive not being restored, sections 58 and 59 of the 1861 Act were repealed. Legal protection for the life of a child who was "capable of being born alive" continued under the Criminal Justice Act (Northern Ireland) 1945.


title: Abortion in the United Kingdom

text: The Executive was restored in January 2020 but legislation on abortion continued to be implemented through Westminster. The Abortion (Northern Ireland) Regulations 2020 were laid before Parliament on 25 March 2020 and took effect on 31 March 2020. The Regulations allowed for abortion in Northern Ireland in the following circumstances:


title: Abortion in the United Kingdom

text: A person who intentionally terminates or procures the termination of a pregnancy other than in accordance with the Regulations commits an offence; this does not apply to a pregnant woman or where the act which caused the termination was done in good faith for the purpose only of saving the woman's life or preventing grave permanent injury. The 1945 Act remains in law, including the offence of child destruction, although this no longer applies to a pregnant woman, or a registered medical professional acting in accordance with the Regulations.


title: Abortion in the United Kingdom

text: The Regulations were replaced by the Abortion (Northern Ireland) (No. 2) Regulations 2020, which were materially the same with minor corrections and came into force on 14 May 2020. As of May 2022, just over two years after the change in the law, abortion clinics and treatments available in Northern Ireland were limited and women seeking to have abortions continued to travel to Great Britain (mainly England).


title: Abortion in the United Kingdom

text: Abortion, as with other sensitive issues, is regarded as a matter of conscience within the main political parties in Great Britain. Conservative, Labour, Liberal Democrat and Scottish National Party representatives, for example, considered and individually decided to vote for or against several proposed changes in the term limit in 2008.


title: Abortion in the United Kingdom

text: In Northern Ireland, for the Social Democratic and Labour Party (SDLP), the Ulster Unionist Party (UUP), and the Alliance Party, abortion is also a matter of conscience, in line with the approach at Westminster. The SDLP previously advocated a pro-life formal party position i.e. consistent opposition to the taking of life alongside providing the utmost compassion and support for the pregnant woman, and opposition to the extension of the Abortion Act 1967 to Northern Ireland; this was changed by the party's membership to a conscience approach in May 2018.


title: Abortion in the United Kingdom

text: The Democratic Unionist Party and Traditional Unionist Voice supported the pre-2019 law on abortion and opposed the legislative changes introduced in 2020 through the Northern Ireland (Executive Formation) Act. DUP MLA Paul Givan introduced the Severe Fetal Impairment Abortion (Amendment) Bill in February 2021, which sought to remove the ground for an abortion in cases of a severe disability in the unborn child (e.g. Down's Syndrome), which was supported by several representatives from other political parties on grounds of conscience.


title: Abortion in the United Kingdom

text: Sinn Féin policy, as approved by its annual conference in June 2018, is for abortion to be available "where a woman's life, [physical] health or mental health is at risk and in cases of fatal foetal abnormality" and "without specific indication ... through a GP led service in a clinical context as determined by law and licensing practice for a limited gestational period". The party previously held a more conservative position, for example in 2007 opposing the extension of the 1967 Act and preferring an approach to crisis pregnancy which involved comprehensive sex education, full access to affordable childcare, and comprehensive support services including include financial support for single parents.


title: Abortion in the United Kingdom

text: Following the policy decisions in 2018 by Sinn Féin and the SDLP, a new political party - Aontú - was formed with a policy of opposing abortion and upholding "the right to life of everyone irrespective of age, gender, race, creed, abilities or stage of development." Aontú has advocated for a "humane and compassionate response" to unwanted pregnancies, including economic support to take mothers out of poverty, pain relief being provided for the unborn child after 20 weeks of gestation, medical care for children who are born after an abortion procedure, and a legislative ban on abortion in cases of disability and gender selection.


title: Abortion in the United Kingdom

text: The Green Party in Northern Ireland and People Before Profit support the full decriminalisation of abortion (i.e. that it should be made available for any reason).


title: Abortion in the United Kingdom

text: Christian Churches and their members support women in crisis pregnancies and/or who have experienced a miscarriage or abortion through practical support and advice and counselling services, either through personal initiative, pastoral ministries, or through specific anti-abortion charities. As in other countries, there is a wide range of personal individual views on abortion within church denominations.


title: Abortion in the United Kingdom

text: The "Catechism of the Catholic Church" states that human life "must be respected and protected absolutely from the moment of conception" and that from the first moment of existence, "a human being must be recognized as having the rights of a person – among which is the inviolable right of every innocent being to life." The Church has affirmed "the moral evil of every procured abortion" since the 1st Century AD and describes direct abortion "willed either as an end or a means" as gravely contrary to the moral law. Pope John Paul II reaffirmed the "Catechism" in his papal encyclical "Evangelium vitae" ("The Gospel of Life") in 1995, which taught on "bringing about a transformation of culture" in relation to abortion and the value of human life, including extensive care and support for pregnant women, their children and their families.


title: Abortion in the United Kingdom

text: During his pastoral visit to Great Britain in 1982, John Paul II remarked: "I support with all my heart those who recognize and defend the law of God which governs human life. We must never forget that every person, from the moment of conception to the last breath, is a unique child of God and has a right to life. This right should be defended by the attentive care of the medical and nursing professions and by the protection of the law." Pope Benedict XVI, on his state visit to the United Kingdom in 2010, stated: "Life is a unique gift, at every stage from conception until natural death, and it is God’s alone to give and to take."


title: Abortion in the United Kingdom

text: The Church of England combines strong opposition to abortion with a recognition that there can be "strictly limited" conditions under which it may be morally preferable to any available alternative. This is based on its view that the foetus is a human life with the potential to develop relationships, think, pray, choose and love. The Church has suggested that the case for further reductions of the time limit for abortions should be "sympathetically considered on the basis of advances in neo-natal care" and has stated that every possible support, especially by church members, needs to be given to those who are pregnant in difficult circumstances.


title: Abortion in the United Kingdom

text: Writing on the 40th anniversary of the 1967 Act, in 2007, the then Archbishop of Canterbury Rowan Williams commented that most parliamentarians who voted for the Act "did so in the clear belief that they were making provision for extreme and tragic situations" but that its implementation since then demonstrated unintended consequences. The strengthening of the language of 'foetal rights' (i.e. that "the pregnant woman who smokes or drinks heavily is widely regarded as guilty of infringing the rights of her unborn child") could be contrasted with "the liberty of the pregnant woman herself to perform the actions that will terminate a pregnancy."


title: Abortion in the United Kingdom

text: The Church of Ireland – a province of the Anglican Communion alongside the Church of England – affirms that "every human being is created with intrinsic dignity in the image of God with the right to life." It has opposed the "extreme abortion legislation" imposed on Northern Ireland, asked that legislation is developed that safeguards the well-being of both the mother and unborn child, and encouraged its members to provide more support to mothers during pregnancy, particularly during times of crisis. In relation to potential grounds for abortion, the Church recognises that there are "exceptional circumstances of strict and undeniable medical necessity where an abortion should be an option (or more rarely a necessity)."


title: Abortion in the United Kingdom

text: The General Assembly of the (Presbyterian) Church of Scotland regards the foetus as "from the beginning, an independent human being" and therefore it can be threatened "only in the case of threat to maternal life, and that after the exhaustion of all alternatives".


title: Abortion in the United Kingdom

text: The Presbyterian Church in Ireland, the largest Protestant denomination in Northern Ireland, is strongly anti-abortion, and maintains that abortion should only be permitted in exceptional circumstances (e.g. where there is a real and substantial risk to the life of the mother) subject to the most stringent safeguards. The Church has affirmed the sanctity of human life, that human life begins at conception, and that complex medical and social issues such as abortion need to be handled with sensitivity and compassion.