The paper presents the optimization of stacking sequence (the lamination angles in subsequent composite layers) of the composite cylinder in order to simultaneously maximize the values of the first natural frequency  In many engineering fields composite materials are used more and more often, e.g., in aircraft, mechanical, environmental or civil engineering ,2. CompoMultilayer composite structures have a remarkable ease of forming various shapes, while each change of the composite structure topology may significantly change their dynamic behavior and/or buckling properties . In caseOptimization is one of the important stages in the design process. The optimization of static and/or dynamic parameters of a composite structure  requires repeatedly calculating the value of the so-called objective function describing the distance of parameters being optimized from their desired values. Real-life engineering problems are typically characterized by more than one objective conflicting with each other. For this reason, an appropriate trade-off between these objective functions should be made using Multi-Objective Optimization (MOO). The computing power demand and time consumption can be reduced if zero-order optimization algorithms are applied (no derivatives of the objective functions are necessary) and modern metamodels of a considered structure are used. The application of nature-inspired metaheuristic algorithms, such as Genetic Algorithms GAs, supported by the use of Neural Networks (NNs) can meet these assumptions ,11.Many works have been done on the vibration, buckling and optimization of cylindrical shells. In , the autAs the design variable the layer fiber orientation may be used, and the multi-objective optimization may also be formulated as the weighted combination of the considered objective functions, dealing e.g., with frequency and buckling force under external load. In , a multithe application of two separate metamodels for the prediction of two parameters being optimized ,application of an internal feedback (loop) for the metamodels refinement,three different approaches to scaling of the objective function arguments,full multi-objective approach vs. scalarization approach leading to single-objective approach,novel definition of the optimal result of multi-objective optimization problem (Nadir point of the Pareto front).In this paper the properties of a composite structure are optimized through the changes of the values of basic topological parameters (lamination parameters). The proposed optimization procedure involves nature-inspired optimization algorithms  such as The analysis of the problems leads finally to a proposition of composite material design by the optimization approach.Once the numerical model of a considered structure is known, the so called initial buckling problem can be described by:KL+μKσKΦ=M3.The investigated structure is a multilayer composite cylinder. The radius of the cylinder middle surface is The finite element model of the investigated structure, shown in The boundary conditions are defined on the shell edges by fixing the translation in all directions (XYZ) at the clamped end of the cylinder. The values of natural frequencies and buckling forces  see . The leaHigher accuracy of the metamodel defined by Equation  is relatapes see . The DNNn stands for the number of patterns divided by 1000).The diagram presented in The vector The number of the mode shapes selected to create the The first buckling force In all the above discussed cases instead of deep networks other data-driven models could be applied, DNNs were chosen since they work very well with huge learning sets and the description of 16-dimensional space of lamination angles needs at least a few thousands examples.The decision of applying the vector The objective function definition requires prior identification of the mode shapes and corresponds to the maximization of the lowest of the natural frequencies matching the selected mode shapes.The main optimization (either MOO or SM) is preceded by the creation of two DNN metamodels, which predicted the model natural frequencies (the The whole optimization procedure (either MOO or SM), together with the metamodels creation phase, is presented in In order to provide a clear description of the metamodels creation procedure a new symbol of o training (coarse grid): patterns) FEM examples for DNNo training: A deep network is trained to map o should be capable of working as function that returns vector DNNo optimization: single-objective GA optimization , it would be advisable to interrupt GA optimization before it reaches any sharp minimum of DNNo approximation of the objective function .GA+DNNK times), a vector of parameters being predicted FEM verification (fine grid around the optimum): For each o optimization following additional DNNo training (retraining).Stop criteria: The usual stop criteria are verified; if the criteria are not fulfilled, the procedure returns to GA+DNNo additional training: The DNNo already trained in the second step of the procedure is trained again (retrained) with the original set of patterns o should then be more precise in the area of the expected global minimum.DNNThe idea, proposed by Miller and Ziemiański in  for maxii in CLi . Since two metamodels are applied, it is possible to refine them separately.The iterative searching for a precise metamodel, described above in Point 6 is called Curriculum Learning (CL). The number of CL loops applied is denoted by o metamodels  environment , the comAccording to the procedure shown in Equation ). The sun shows the number of patterns divided by 1000. The improvement of the maximization results with the increase of the number of employed metamodel training patterns is clearly visible; however, over 8000 of patterns the increase disappears. For the main task—the simultaneous maximization of Each of boxes in The maximal value of Curriculum Learning loop—presented in In the second initial step to the main optimization procedure the metamodel For the main task, the simultaneous maximization of The maximal value of The metamodels Equation . After if GA see ). The op(a)no scaling at all: (b)scaling to an arbitrarily selected lamination angles case: (c)scaling to maximal values of Three different variants of scaling factors pairs (see Equations  and 16)16)) haveAs a result of each of the above described 250 repetitions of MOO a cloud of points is obtained, each of them being an element of one of 250 so called Pareto Fronts (PFs) obtained in each of the repetitions. Pareto front is a border line between the feasible and the infeasible results, given in the optimized parameters’ space, here in UP, see ,31) at t at t(f1⋆Although the points in (a)scaling to an arbitrarily selected lamination angles case: (b)scaling to maximal values of Here the normalization factors in the objective space are This approach to the selection of NP prefers one or the other of the minimized values , another approach is thus proposed. The analysis of The same metamodels (Equation . After if GA see ). The opThe results, obtained for scaling factors The best values of The same results are shown (in green) also in The results obtained from MOO and SM optimization are gathered in The differences between scaling scenarios are negligible, there is however subtle but clear advantage of SM over MOO approach.The above described maximization of The results gathered in m of the cylinder. The horizontal axis of m is an overall mass and The analysis of two separate metamodels,CL loops for metamodels refinement,multi-objective optimization with two objective functions, orscalarization method approach, where the only scalar objective function is a linear combination of two objective functions involved in the previous approach.The paper presents the optimization of stacking sequence (the lamination angles in subsequent composite layers) of the composite cylinder in order to maximize simultaneously values of the first natural frequency no scaling at all: scaling to an arbitrarily selected lamination angles case: scaling to maximal values of Moreover, three different scaling of the input data for the optimization procedure are verified:New proposition of ND  selection is also proposed.In the presented examples the scalarization method gives slightly better results, while the three investigated scaling approaches are barely distinguishable.The two neural network metamodels substitute very time- and resource-consuming FE calculations. The metamodels are created using examples obtained through FEM, but once the metamodels are ready they are able to assess the values of The applied metamodels enable the precise tuning of the investigated structure parameters, it is possible to obtain such a values of the design parameters  that the value of the fundamental natural frequency reaches a value close to its maximum, simultaneously with the buckling force also being near its maximum. In fact in every considered case the final solution gives the values of both Genetic algorithms and DNN are very suitable tools to find global  optimal solution in the analyzed problems, where laminated composite is used.The presented approach allows to design cylinder composite material through optimization approach.other parameters—like overall mass and/or stiffness—should be taken into account,wider range of control variables, also some geometric and/or material properties should be considered,CL approach on the level of the whole MOO procedure should be applied, not only on the level of metamodel creation.The research should be carried out further, the following problems should be addressed:


The outbreak of novel coronavirus pneumonia (coronavirus disease 2019 (COVID-19)), declared as a ‘global pandemic’ by the World Health Organization (WHO), is a public health emergency of international concern (PHEIC). The outbreak in multiple locations shows a trend of accelerating spread around the world. China has taken a series of powerful measures to contain the spread of the novel coronavirus. In response to the COVID-19 pandemic, in addition to actively finding effective treatment drugs and developing vaccines, it is more important to identify the source of infection at the community level as soon as possible to block the transmission path of the virus to prevent the spread of the pandemic. The implementation of grid management in the community and the adoption of precise management and control measures to reduce unnecessary personnel movement can effectively reduce the risk of pandemic spread. This paper mainly describes that the grid management mode can promote the refinement and comprehensiveness of community management. As a management system with potential to improve the governance ability of community affairs, it may be helpful to strengthen the prevention and control of the epidemic in the community. Since the outbreak of novel coronavirus pneumonia (coronavirus disease 2019 (COVID-19)), the community is the most important place to prevent the spread of the epidemic[The identities of community members are complex and the mobility of personnel is high, so there are many uncertainties. It is difficult to implement various prevention and control measures in the traditional and decentralised community management mode. The novel coronavirus pneumonia has the characteristics of long incubation period and diversified infectious pathways . At presThe community grid management is to divide the urban area into several community unit grids according to the scientific standards such as geographical layout, convenient management and integrity of management objects, and each community unit grid is divided into sub-grids again depending on the community-level information platform. Using the electronic information and data platform to accurately and quickly locate the community grid units is conducive to orderly distribution of prevention and control materials and timely resolution of public health crisis during epidemic prevention and control. Through the active inspection of the epidemic situation in the unit grid, the prevention and control measures can actively intervene, rapid response and efficient treatment, to greatly improve the execution efficiency in the unit grid. The anti-epidemic data information of each community grid unit is timely shared and interconnected. Neighbouring community grid units shall establish a regional integration cooperation mechanism, complement each other in anti-epidemic materials and human resources and implement joint prevention and control measures. The community-level information platform timely announces the progress of anti-epidemic measures. Collect residents' opinions through Internet application software and dedicated telephone lines, and respond to residents' concerns in a timely manner. The community grid management should establish a team of epidemic prevention and control personnel in the community grid unit. These personnel compose of volunteers who are familiar with the actual situation of the community and residents who have some experience in community management. The epidemic prevention materials of grid prevention and control personnel should be fully guaranteed and they should be trained in epidemic prevention knowledge. The task of grid prevention and control was clearly divided and carried out in an orderly manner to ensure that the work responsibilities are assigned to specific prevention and control personnel.At the community level, the knowledge and measures of epidemic prevention and control should be publicised to obtain support and cooperation from residents, and all residents in the community should be fully mobilised to implement various measures of community grid management. It is suggested that the community grid prevention and control personnel be divided into several prevention and control groups, such as the entrance and exit control group, the material assurance group, the disinfection group, the grid inspection group etc. The staff of the entrance and exit control group are responsible for the pre-check and identity verification of the people entering and leaving the community, and the registration of the movement track of the people entering and leaving the community. All the people entering and leaving the community need to check their temperature, wear masks and strictly restrict the entry of outsiders into the community. The staff of the material assurance group are responsible for the purchase of protective clothing, masks, infrared temperature guns, disinfectant water and other anti-epidemic substances, arranging special personnel to be responsible for registration and distribution, helping community residents purchase daily requirements, coordinating material procurement channels and storage places and doing a good job in logistics support such as emergency supplies storage. The staff of the disinfection group are responsible for regular disinfection in public places and places with high risk of virus transmission (such as handrails and elevator buttons). The staff of the grid inspection group are responsible for the evacuation of people gathered in the community grid unit.During the epidemic prevention and control period, relying on the big data information platform, information data is shared with disease control departments, medical institutions and anti-epidemic departments to improve prevention and control efficiency. Emergency patients in urgent need of medical treatment shall be transferred to medical institutions by specially assigned persons to reduce the risk of epidemic spread caused by residents' going out for medical treatment.


Silicone resins are widely applied as coating materials due to their unique properties, especially those related to very good heat resistance. The most important effect on the long-term heat resistance of the coating is connected with the type of resin. Moreover, this structure is stabilized by a chemical reaction between the hydroxyl groups from the organoclay and the silicone resin. The novel trends in application of silicone resins in intumescent paints used mostly for protection of steel structures against fire will be presented based on literature review. Some examples of innovative applications for fire protection of other materials will be also presented. The effect of silicone resin structure and the type of filler used in these paints on the properties of the char formed during the thermal decomposition of the intumescent paint will be discussed in detail. The most frequently used additives are expanded graphite and organoclay. It has been demonstrated that silicate platelets are intercalated in the silicone matrix, significantly increasing its mechanical strength and resulting in high protection against fire. Silicone resins and branched polysiloxanes with very good thermal resistance are widely used as components of coating materials to meet the requirements of different applications. These compounds can be used to coat various materials, including building materials, ceramics, and construction elements. One of the examples of demanding applications are steel and aluminum structures used in construction, which must be adequately protected against fire in order to maintain their load capacity for a specified period of time, enabling the evacuation and protection of the object. Under fire conditions, the temperature of steel structure elements rises very quickly, reaching the limit temperature in which a loss of mechanical properties occurs. The result is deformation of the structural elements and their collapse. Depending on the type of fire source and its intensity and the massiveness of the structural elements, the critical temperature of steel (450–550 °C) can be reached within a few minutes. The reason for the loss of mechanical properties of steel at elevated temperatures may be stresses related to thermal expansion . Steel cHistorically, the first way to create an insulating barrier against the inflow of heat was to enclose the steel structure in a concrete cover . The next applied solution was the use of spraying cement or gypsum masses filled with light porous material (which can expand under high temperature conditions), e.g., polystyrene granules, perlite, vermiculite, or mineral fiber materials. These solutions had very limited applications due to the weight of the insulating layer and corrosive properties of cement mixtures which require the initial protection of steel.Good effects in protection of steel structures against fire are achieved through the use of intumescent paints capable of producing a sintered layer during a fire, isolating the steel structure from high temperature. The best protection of the structure can be obtained when the sintered layer is formed in a controlled manner with the formation of a layer with an appropriate thickness from 1 mm to 10 cm . The basUnfortunately, it should be noted that typical organic binders used to make intumescent paints have a number of disadvantages. First of all, organic binders undergo thermal decomposition with the release of toxic gaseous products. It also causes a deterioration of the thermal insulation properties of the coating because the sintered layer is cracked and has insufficient cohesion. An additional factor causing the imperfections of the sintered layer is a softening point that is too low and thermal decomposition of organic binders, which disturbs the formation of this layer . All theAt this point, a second inorganic type of intumescent coatings based on alkali silicate  should aThe aim of this review is to present the most important information concerning silicone fire-retardant intumescent paints based on a literature review made using the following keywords: intumescent paint, silicone resin, fire protection of steel or aluminum structures, silicone intumescent paint application. Literature review was made using the following databases: Web of Knowledge, Scopus, and Google Scholar. The research also covered Espacenet, Patentscope, and Google Patents, which resulted in the presentation of selected patents relevant to the subject. The overview is divided into the following main sections including discussion focused on the effect of silicone resin structure on its thermal stability, the effect of silicone resin structure, and the type of filler used in these paints on the properties of the char formed during the thermal decomposition of the intumescent paint and most important innovative applications of these paints.The properties of silicone resins differ significantly from those of linear polysiloxanes. The main factors causing these differences are their branched structure and the presence of various types of organic substituents attached to silicon atoms by a Si−C bond. In the synthesis of polysiloxanes, monomers with different degrees of branching are used see .The term ‘‘branched structure’’ means that the polysiloxane contains T or Q units in its chain. The measure of the degree of branching is the ratio of organic groups to silicon atoms (R/Si). The lower R/Si ratio is the higher content of the T units and the branched extent. In the thermogravimetric study of branched and linear polysiloxanes, it was found that thermal stability of branched polysiloxanes was higher as compared to linear ones . The exaAs shown above, the thermostability of methylphenyl silicone resins depends on their structure expressed by the degree of branching R/Si and on the content of phenyl groups. This gives a very good opportunity to select the resin with the most appropriate parameters necessary to create a good-quality sintered layer created by intumescent paint.The selection of the appropriate type of resin is of great importance for obtaining the desired final effect of fireproof intumescent paints because the process of a protective layer formation is complex and multi-stage, as detailed in 3PO4 enables further esterification reaction of the hydroxyl groups present in char formers and the polymer binder. A further increase in temperature causes decomposition of esters with the formation of carbon, free acid, water, and carbon dioxide. The decomposition of esters is accompanied by the release of a significant amount of inert gases from the decomposition of blowing agents. The composition and properties of the individual components of the intumescent paint should be selected in such a way that inert gases are released. This causes the protective layer to swell and then harden into char , and sepiolite) , zirconi2 , carbon 2 , nano -Schitosan . Yasir echitosan  conducteThe significant progress in the technology of intumescent paints related to the introduction of new binders with increased thermal resistance, such as, for example, silicone resins capable of reacting with properly selected fillers, contributes to the constant trend of increasing the range of applications of these paints. This trend concerns not only the size of the market, but is also related to the development of new types of paints that give good effects not only on steel but also on other substrates requiring very good fire protection, such as plastics, fabrics, cellulose or wooden products. According to the report Research and Markets  the markIn a Goldstein Research  report pIt should be noted that the intumescent fireproof coating is one of the easiest and most effective methods of protecting materials, used not only for metal surfaces, but also for plastics, steel, wood, electric cables and polymer composites. This method of protection does not cause chemical modification of the substrate, but rather the formation of a protective layer that changes the heat flux acting on the substrate and may inhibit the temperature of its degradation, ignition or combustion . Even inThe stability of the carbonized protective layer is crucial to ensuring fire safety in high-rise buildings. It was found that the addition of non-purified fullerene-containing soot with different structure  and graphite’s microparticles allows to obtain a protective layer with increased strength . The useIntumescent paints are also used to protect plastic surfaces. Beaugendre et al.  investigGood durability of the coatings and adhesion between all types of coatings and the substrate were found, indicating the possibility of using intumescent paints to protect glass fiber-reinforced epoxy composites. It can be stated that the protective layers formed from coatings obtained from intumescent paints are increasingly used not only to protect steel structures but also other materials such as building materials and plastics. There are a number of original recipes of these compositions enabling the protection of buildings, e.g., tunnels, vehicle protection and even flexible laminates used in displays in modern electronics.The use of silicone resins as binders or their components in intumescent paints is important to obtain the desired parameters of the fireproof layer. The variety of structures of silicone resins and the degree of their branching enables the selection of a binder with appropriate thermal stability so that its thermal degradation takes place at the appropriate temperature at which the sinter layer is formed and that the paint layer does not soften too early, causing it to run off. Based on the literature review, it has also been shown that the parameters of the protective layer are also influenced by the type of organic substituents in the structure of the silicone resin, especially the appropriate content of phenyl groups increasing the thermal stability of the binder. The selection of appropriate fillers has a significant impact on the parameters of the protective layer. Many studies have found that fillers such as chalk, organoclay or expanded graphite have the ability to integrate into the structure of the protective layer formed with the use of silicone resin as a paint binder. This is due to the presence of reactive silanol groups capable of reacting with the functional groups present in the fillers. The properties of the protective layer are also influenced by the structure of the fillers, especially fibrous or layered, which strengthens the mechanical properties of the protective layer. These properties significantly affect the insulation parameters. Based on the examination of many factors influencing the insulating properties of the intumescent layer, it was found that the net heat flux through this layer and the layer structure, mainly in terms of its porosity, as well as the multilayer structure seem to have a significant effect. The material on which the protective layer is placed and their compatibility are also important. The test results correlate well with the results of modelling the insulation of protective layers. Taking into account so many different factors, it seems reasonable to use mathematical modelling, which is a good engineering tool. However, due to the constantly developing area of covering construction and building materials, it is necessary to further develop this tool, taking into account also the scope of fire safety.The unique properties of intumescent paints, which enable adequate protection of not only steel structures, but also other building materials and plastics, contribute to the constant increase in the use of these paints, thus increasing the safety of people and property during a fire by extending the time necessary to evacuate endangered objects.Summarizing the information presented and taking into account the architectural tendencies towards increasingly daring, tall forms of steel structures, it should be assumed that the market of intumescent firestop paints will continue to grow intensively. High aesthetics of protective paint coatings and their low weight are advantages inherent in the construction technology of such objects, which are difficult to obtain in other ways. New publications gradually reveal new technical solutions in this field, introducing systems of hybrid paints, intumescent paints with the addition of retardants, new, much more flexible paint binders, as well as new paints using the experience of advanced nanotechnology, allowing for better effectiveness of the fireproof barrier of the coating at lower coating thicknesses.


All three subfamilies  of herpesviruses undergo a maturation phase during replication that initiates in the nucleus of the infected cell with encapsidation of viral DNA to form nucleocapsids. These nucleocapsids are transported across the nuclear membrane into the cytoplasm utilizing a sophisticated nuclear egress complex (NEC). Cytoplasmic phase of virus maturation includes tegumentation and envelopment of nucleocapsids. Herpesvirus tegument proteins play important roles in maintaining the stability of capsids and directing the acquisition of virus envelope. The maturation concludes with the envelopment of nucleocapsids, which occurs at modified host membranes in the cytoplasm and exploits host vesicular trafficking. The entire process of virus maturation is orchestrated by protein-protein interactions and enzymatic activities of virus and host origin.Close et al. focuses on the contribution of endocytic recycling compartment to human cytomegalovirus (HCMV) maturation and egress. They make a strong case that cellular transport systems are engaged by HCMV in a systemic manner for successful maturation and egress. They utilize tools in advanced transcriptomics and proteomics married with computational analysis to come to these conclusions. Earlier studies by the same group as well as other groups have alluded to this engagement process. Close et al. argue that the composition and behavior of endosecretory organelles change during the biogenesis of cytoplasmic virion assembly complex . Infection-associated changes in gene expression suggest shifts in the balance between endocytic and exocytic recycling pathways, leading to the formation of a secretory trap within the cVAC. Also, a shift toward outbound secretory vesicle trafficking indicate a potential role of cVAC in virion egress. The analysis of signaling pathways lead them to model the behavior of endocycling recycling compartment (ERC) during HCMV replication.Herpesvirus maturation remains one of the least studied yet most complicated part of virus life cycle and numerous host and viral factors appear to influence the outcome. The current collection contains three articles contributed by nine authors. These articles have already gathered nearly 5,000 views and continue to gather attention from scientists and non-scientists alike who are willing to delve deep into the mysteries of herpesvirus maturation. The first article by Grosche et al. discusses HSV-1 replication in monocyte-derived dendritic cells (DCs). HSV-1 completes its gene expression profile in immature as well as mature DCs; however, lytic infection only occurs in immature DCs and mature DCs fail to release infectious progeny into the supernatant pointing toward differences in virus maturation and release. This article provides a commentary on viral as well as host factors responsible for these differences.The article by Heilingloh and Krawczyk focuses on the significance of production of non-infectious L-particles during HSV infection and discusses their biological functions. These particles are mostly composed of viral tegument proteins and are devoid of viral DNA and capsids. L-particles seem to undergo similar maturation and egress as the infectious particles and their generation is therefore interesting to investigate in order to understand the process of virus maturation.The article by We believe that maturation of herpesviruses will be an area of continued interest in virology as new virus and host players continue to emerge. The dramatic reorganization of the host endosecretory system leading to the formation of cVAC has mainly been appreciated in HCMV infected cells and deemed as the site of virion assembly. The debate is still on the floor whether this cVAC is a functional component of the virus maturation pathway or is merely an after-effect of virus replication. Although a typical cVAC is not seen during infection with other herpesviruses, a perinuclear site of virus maturation in cytoplasm has been recognized in most. Future studies in this area should focus on the identification of functional interactions among host and viral factors that determine virus maturation as well as structural characterization of the site of virus maturation in cells using advanced techniques in fluorescence and electron microscopy.All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Leonardo da Vinci (1452–1519) presented the first morphological drawing of the coronaries of animals in his famous anatomical sketches (c 1485 Florence).2 In Padua, Vesalius (1514–1564) published his classical work De Humani Corporis Fabrica (1543) with the first anatomical drawing of the coronaries from autopsy studies of the human body.3 Also, at the illustrious University of Padua, William Harvey discovered the functional system of blood circulation in 1628 laying the foundations of modern experimental medicine.4 On 21 July, 1768 William Heberden delivered a lecture before the Royal College of Physicians of London on a disorder of the breast,5 a form of chest pain which he describes as follows: “But there is a disorder of the breast marked with strong and peculiar symptoms, considerable for the kind of danger belonging to it, and not extremely rare, which deserves to be mentioned more at length. The seat of it and the sense of strangling and anxiety with which it is attended, may make it not improperly be called angina pectoris". After his masterly description of the chest disorder which Heberden called angina pectoris, it took more than 150 years before the syndrome was linked to its true etiology.The coronary circulation was discovered in the 13th century by Ibn al Nafis (1213–1288).6 For a long period, this led to the hypothesis of Jenner that calcifications were the origin of angina pectoris as has been published in 1793 (London).7 But as a result of the animal experiments of John Erichsen in 1842 (London),8 in which he ligated the proximal coronary arteries it became clear that occlusion of the coronary arteries may cause a fatal cardiac event: “…that the arrest of the coronary circulation produces a speedy cessation of the heart’s action. Secondly, that an increase in the quantity of blood sent into, or retained in the muscular fibre of the heart, produces a corresponding increase in the activity of that organ.”In the meantime Morgagni  published on calcifications in the coronary arteries of an old male.9This was the beginning of coronary ligation experiments for physiological studies of myocardial perfusion to the present day. In 1907, the visualisation of the coronary arteries by X-ray was published in an atlas composed from the analysis of human cadavers by Jamin and Merkel.10 This publication triggered the interest to visualise the coronary arteries in the living human body. Rosthoi performed the first left ventriculography and coronary visualisation in an animal experiment in 1933.11 Radner from Sweden realized the first “in vivo” coronary angiogram by direct sternal puncture of the ascending aorta in the year 1945.12 After this very drastic approach followed a period when catheters were inserted in the arterial system from the femoral artery and contrast was injected in the aorta at the level of the aortic root, while selective coronary contrast injection in the coronaries was regarded as a potential cause of iatrogenic mortality and was avoided. On 30 October, 1958, during such an angiographic procedure performed by Sones, the catheter accidentally stuck in the main coronary stem and the first selective cine frame coronary arteriogram was recorded.13 To the astonishment of the medical community, the patient survived without any sequalae. This positive outcome promoted diagnostic coronary angiography for the diagnosis of morphological coronary changes as a proof for the origin of chest pain, because those changes were regarded to be the key etiology for hypoxemia of the myocardium. Diagnostic coronary angiography and percutaneous transluminal angiography were developed through the 1960s and 1970s by the radiological research of Dotter14 with diminishing procedure related complication and mortality rates. As radiologist Gruentzig performed the first percutaneous transluminal coronary angioplasty on 16 September, 1977 in Zurich Switzerland.15 The nonsurgical treatment of coronary stenosis by angioplasty unleashed the medical specialty of the interventional cardiologist focusing on the treatment of coronary stenosis by angioplasty and stenting as the solution to prevent myocardial ischemia and hypoxemia. However, this monocausal approach led to substantial overdiagnosis and overtreatment of coronary artery stenosis.After this long period of hypothesising and speculating by the medical scientific community on the origin of angina pectoris, in 1928 Chester Keefer and William Resnik stated that from all available evidence angina pectoris is caused by anoxemia of the myocardium.16 In 2001, 4-Multi Detector CT Systems became available with rotation times lower than 500 ms enabling the noninvasive visualisation of the coronaries.17 It took almost 20 years of further development of coronary CT angiography before it could establish a major position in the diagnostic work-up of patients with chest pain. Systematic population research with CT examinations showed that the majority of people will develop coronary artery calcification and stenosis with ageing without any consequences for the oxygenation of the myocardium. This led to the insight that the majority of coronary stenoses do not need treatment, because there is no effect on the perfusion of the myocardium by flow redistribution and collateral flow mechanisms. This in turn resulted in a sharp rise of noninvasive diagnostic CT evaluation of the coronaries in patients with chest pain to rule out the many different pathologies that were already described by Heberden in 1768. Moreover, noninvasive coronary CT angiography is now used to diagnose and select the coronary pathologies that need (immediate) revascularization therapy by percutaneous coronary intervention or coronary artery bypass grafting. We reached the point that invasive diagnostic coronary angiography is hardly ever indicated and invasive procedures should be reserved for coronary treatment procedures alone.In 1988, the first continuously rotating CT systems became clinically available with rotation times lower than 1s.18 a new era of noninvasive coronary imaging opens up. The study proved that replacing the diagnostic work-up by noninvasive coronary CT imaging in patients with chest pain, as a first-line modality, results in a substantially lower mortality rate compared to a diagnostic strategy without this noninvasive diagnostic modality. Only 6 months after the SCOT-HEART publication, the final evidence was published that noninvasive myocardial perfusion MR can rule out all patients with significant coronary pathology but without any impact on myocardial bloodflow.19With the recent publication of the SCOT-HEART study,BJR special feature is dedicated to these landmarks and aims to open up the horizons of the many new applications that will dramatically change the current medical practice. The special feature includes an overview of the SCOT-HEART trial and its impact on CCTA for patients with stable ischemic heart disease20, as well as a review of cost-effectiveness for imaging stable ischemic disease21. Furthermore, the collection gives a detailed review of the potential for functional coronary and cardiac CT imaging beyond the evaluation of the coronary artery lumen22, the potential role of noncardiac findings in risk stratification23 and the role of machine learning to drive forward enhanced imaging data analysis.24,25 In addition, the role of MRI for the assessment of chest pain is of great importance26–28, as is the role of imaging in the evaluation of heart valve disease29. Lastly, novel methods for the evaluation of heart viability and coronary artery disease30, with a focus on developing ways to assess vulnerable plaque31,32, are coming to the fore and are reviewed.This BJR special feature marks the moment of publication of the first hard evidence that noninvasive coronary CT imaging in patients with chest pain saves lives compared to current medical practice and at the same time is a lot less harmful for the patient, costs less and is more effective. The special feature appears also at the moment of 125 years of publishing radiological research in BJR. BJR is the oldest radiology journal in the world and this excellent collection of articles demonstrates that the journal remains at the cutting edge of radiological research publishing. This fascinating collection will be of value to any medical professionals interested in stable chest pain. The Guest Editors would like to thank all of the authors for contributing their work as well as the expert reviewers who helped review it. We hope our readers enjoy the collection!This


Testicular androgens during the perinatal period play an important role in the sexual differentiation of the brain of rodents. Testicular androgens transported into the brain act via androgen receptors or are the substrate of aromatase, which synthesizes neuroestrogens that act via estrogen receptors. The latter that occurs in the perinatal period significantly contributes to the sexual differentiation of the brain. The preoptic area (POA) and the bed nucleus of the stria terminalis (BNST) are sexually dimorphic brain regions that are involved in the regulation of sex-specific social behaviors and the reproductive neuroendocrine system. Here, we discuss how neuroestrogens of testicular origin act in the perinatal period to organize the sexually dimorphic structures of the POA and BNST. Accumulating data from rodent studies suggest that neuroestrogens induce the sex differences in glial and immune cells, which play an important role in the sexually dimorphic formation of the dendritic synapse patterning in the POA, and induce the sex differences in the cell number of specific neuronal cell groups in the POA and BNST, which may be established by controlling the number of cells dying by apoptosis or the phenotypic organization of living cells. Testicular androgens in the peripubertal period also contribute to the sexual differentiation of the POA and BNST, and thus their aromatization to estrogens may be unnecessary. Additionally, we discuss the notion that testicular androgens that do not aromatize to estrogens can also induce significant effects on the sexually dimorphic formation of the POA and BNST. Sex differences in the structures of the brain are considered to underlie sex-specific functions of the brain and brain functions that differ between sexes or genders. The mechanisms by which the brain is sexually differentiated have not yet been completely elucidated; however, they have long been studied using animal models, especially rodents. Based on accumulated data, androgens secreted from the testes during the perinatal period are converted to estrogens in the brain, wherein the neuroestrogens masculinize and defeminize the brain. Neuroestrogens are essential but not sole factors in the sexual differentiation of the brain. There are other factors that significantly contribute to the brain sexual differentiation. The processes of brain sexual differentiation require sex chromosome genes’ expression in the brain  and gonaThe POA and BNST show morphological sex differences that are related to sex-specific brain functions . The numIn the POA of rats and mice, there are two sexually dimorphic nuclei that have been identified to date. The sexually dimorphic nucleus of the POA (SDN-POA) exhibits male-biased sex differences in volume and the number of neurons , 1980. TAnother sexually dimorphic nucleus in the POA is the anteroventral periventricular nucleus (AVPV), which is larger and contains more neurons in females than in males . The AVPThe principal nucleus of the BNST (BNSTp) is a subnucleus of the BNST showing male-biased sex differences in size and neuron number , 1992. LNeuroestrogens originating from testicular androgens affect the POA and BNST in the perinatal period to organize sexually dimorphic structures in a variety of modes of action . As mentBax gene did not affect the number of Calb neurons in the CALB-SDN of mice in both sexes   and AR-kPerinatal testicular androgens induce masculinizing and defeminizing effects on the POA and BNST of rodents through binding to ER after conversion to estrogens in the brain rather than by binding to AR directly, resulting in sex differences in glial and immune cells, dendritic synapse patterning, and specific neuronal cell groups. Interactions among immune cells, glial cells, and neuronal cells under the influence of neuroestrogens is a prerequisite for producing the sex difference in dendritic synapse patterning in the POA. Sex differences in specific neuronal cell groups in the SDN-POA, AVPV, and BNSTp may be established by controlling the number of dying cells by apoptosis or phenotypic organization of living cells that are influenced by neuroestrogens. Neuroestrogens binding to ER modulate the expression of the target genes at the transcriptional level, but also modulate gene expression by epigenetic regulation, which ensures the long-lasting effects of neuroestrogens beyond the perinatal period. Testicular androgens in the peripubertal period also contribute to the sexual differentiation of the POA and BNST, but aromatizing them to estrogens may not be necessary. Thus, peripubertal testicular androgens can act via AR directly to masculinize the sexually dimorphic nuclei.MM and ST prepared the manuscript. Both authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Metal-organic frameworks (MOFs) offer a unique variety of properties and morphology of the structure that make it possible to extend the performance of existing and design new electrochemical biosensors. High porosity, variable size and morphology, compatibility with common components of electrochemical sensors, and easy combination with bioreceptors make MOFs very attractive for application in the assembly of electrochemical aptasensors. In this review, the progress in the synthesis and application of the MOFs in electrochemical aptasensors are considered with an emphasis on the role of the MOF materials in aptamer immobilization and signal generation. The literature information of the use of MOFs in electrochemical aptasensors is classified in accordance with the nature and role of MOFs and a signal mode. In conclusion, future trends in the application of MOFs in electrochemical aptasensors are briefly discussed. The scheme of the reactions is outlined in These protocols are based on the fact that specific aptamer–analyte interactions result in the implementation of bulky inert molecules preventing the access of redox-active species to the electrode surface and hence decreasing their signal recorded by voltammetry. Alternatively, increased charge transfer resistance can be recorded in the presence of the 3−/4− redox indicator is applied so that the sensitivity of both methods is expected to be close to each other. However, voltammetry often shows slightly lower limits of detection (LOD) than EIS contrary to the common behavior of similar immune- and DNA sensors.For this reason, the electrodes are additionally treated after the aptamer immobilization with inert organic thiols, preventing such adsorption. 6-Mercaptohexanol is used in many protocols due to its hydrophilicity and easy attachment to the naked part of the electrode. In both EIS and DPV measurements, a 3−/4− indicator remains the most frequently used in aptasensors, other species have found increasing application for signal generation. Some of them denoted as labels are attached to the carrier or electrode surface while other ones (redox indicators) are diffusionally free and can be accumulated in the surface layer due to analyte binding. In case of MOFs, they can serve as specific sorbents for redox-active species. Their activity is then used for the signal measurement. Thionine 3−/4− to a rather small extent if common approaches of the biosensor assembling are used.All of the above mentioned is applicable for electrochemical aptasensors utilizing MOFs to enhance surface square, immobilize aptamers, and generate redox signals. The use of bulky and electrochemically inactive aptamer molecules makes the aptasensor behavior sensitive toward the conditions of electron transfer. Contrary to electroconductive carbonaceous materials, MOF particles offer a shuttle mechanism of the electron exchange with participation of both free and immobilized mediators, including the metals as counterparts of the MOF structure. Such an electron transfer path is easily broken by the inclusion of analyte molecules. For this reason, aptamers based on the MOF structures often show a record sensitivity of detection especially for small analyte molecules that affect the transfer of conventional redox indicators like [Fe(CN)Although most of the articles devoted to the electrochemical aptasensors based on MOF materials do not provide a comprehensive comparison of the characteristics with conventional analogs, it can be concluded that introduction of MOF particles can decrease the LOD values by at least one order of magnitude against the application of similar heterogeneous mediators of electron transfer. The difference might be even higher if MOF particles are used as parts of indicators attached to the electrode interface via target biochemical interactions with analytes. These benefits follow from the size of the particles and multiplication of the signal due to the much higher number of redox sites involved in the electron transfer. Appropriate examples are presented in Summarizing the modern progress in the development of aptasensors based on the MOF materials, one can conclude that further achievements can be expected from the broadened application of hybrid MOF-on-MOF and MOF@MOF particles that combine the advantages of several metals and linkers and can be easily adapted to a particular measurement mode or signal detection requirements. Thus, the use of such hierarchic materials with Ru bipyridine complex shows high efficiency of electrochemilumenscent measurements . Such hyThe variety of hybrid particles can also be extended by variation of the organic linkers and conditions of the synthesis, which can involve chemical and electrochemical steps and variation of the solvents and temperatures applied. A similar conclusion can be made about MOF-derived materials, where the initially synthesized MOF particles are then calcinated at high temperature or treated with chemical reagents. The products do not formally belong to the MOF family but retain the porosity, specific shape, and high adsorption capacity typical for precursors. Although many such derived materials have an alternative path of synthesis, the use of MOF precursors might be beneficial from the point of view of simplicity, and labor and time intensiveness.The following trends in the further progress of MOF-based aptasensors can be mentioned.Faster progress is expected in the multiplex assay and simultaneous determination of several analytes based on the number of aptamers introduced in the aptasensor structure.Growing interest will be directed to the signal-on aptasensors, where an increased concentration of the analyte increases their response. This kind of sensor seems more beneficial both from the point of view of metrological assessment of the results and application of the aptasensors in the real sample assay.Although the term ‘MOF’ is mostly related to the use of the linkers with carboxylic binding groups, the variety of the organic part of the MOFs will be increased by the introduction of new structures and precursors derived from imidazole fragments and some others exerting an unusual architecture of the internal space of the particles and their morphology.The interest in the synthesis of new MOF materials will be shifted to their implementation in supramolecular structures consisting of supramolecular polymers and aptamer molecules.In general, the high variability of the MOF structures and their easy accessibility as building blocks of aptasensors make it possible to rely on their broad application in medicine, food industry, and environmental pollution monitoring.


First Person is a series of interviews with the first authors of a selection of papers published in Biology Open, helping early-career researchers promote themselves alongside their papers. Jing Liu is first author on ‘ Jing LiuWhat is your scientific background and the general focus of your lab?in vitro fertilization. Dr Song pays close attention to the effects of oxidative stress on female reproductive health.While studying for my doctorate, I explored the correlation between oxidative stress and endometriosis under the guidance of Dr Quan and Dr Song. I tried to investigate if advanced oxidation protein products (AOPPs), as the products and triggers of oxidative stress, could affect the biological behaviours of endometrial cells and further promote the development of endometriosis pathogenesis. Over the years, Dr Quan has focused on the pathogenesis of female infertility and the mechanism of repeated implantation failure in How would you explain the main findings of your paper to non-scientific family and friends?In the body, oxidation and anti-oxidation are kept in balance. When the balance is broken down, the organism will fail ill. AOPPs are the products of oxidative stress and can trigger oxidative stress. Our research found that overabundant AOPPs could change the biological behaviour of rat endometrial epithelial cells (rEECs) proliferation, migration and apoptosis. At the same time, the production of oxidative stress in rEECs ROS and nitrites both increased, and signalling pathways also were activated. We also confirmed in animal models that AOPPs could promote ectopic endometrial tissue growth by inducing endometrial cell proliferation and migration.What are the potential implications of these results for your field of research?Abnormal cell behaviours are closely related with the occurrence of various diseases. Increased proliferation and migration of endometrial epithelial cells could contribute to the progression of endometriosis. Previous studies have stated that the accumulation of AOPPs in body fluid were associated with endometriosis. In our research, AOPPs could induce rEECs proliferation and migration by activating ERK/P38 signalling pathways, and promote the growth of ectopic endometrial tissue. These findings showed that the accumulation of AOPPs could contribute the development of endometriosis pathogenesis by activating ERK/P38 signalling pathways.What changes do you think could improve the professional lives of early-career scientists?When we focus on our professional research, we should keep a sharp eye on the newest research progress and research techniques in various fields. New research techniques can provide us with creative experiment design. To open our eyes to different fields would help us with active thinking. In the future, multidisciplinary research will be the mainstream and the birthplace of great breakthroughs.“In the future, multidisciplinary research will be the mainstream and the birthplace of great breakthroughs.”What's next for you?I plan to study the correlation between AOPPs and human endometrial cells further, and try my best to explore the effects of AOPPs on the endometriosis-related infertility. As a clinical doctor, I also need improve my clinical skills in assisted reproductive technology and combine basic research with clinical problems to help more women that are infertile.


Objective. The current paper presents an interesting case of facial reconstruction after the excision of a giant basal cell carcinoma located in the orbitofrontal region. Methods. Performing the excision while securing the appropriate oncologic safety margin has determined the appearance of a soft tissue defect that required a complex reconstruction using three regional flaps: frontal, temporal fascial and temporal muscle flaps.Results. After the excision and reconstruction in a single surgical stage, the postoperative result was favorable, the 12 months assessment showing that the patient was satisfied with the aesthetic aspect.Conclusion. Including the orbital exenterations in the excisional treatment of giant neoplasms located in the facial region requires a complex reconstructive plan. The surgical team has to consider the relief of the anatomical structures that are targeted, as well as the necessity of achieving satisfactory aesthetic results while ensuring oncological radicality. The excision of tumors located in the facial region requires the entire plastic surgeon’s armamentarium, considering the margins of oncological safety and subsequently reconstructing the anatomical regions affected by the neoplastic process. Regarding the cephalic region, the patients’ degree of tolerance related to the aesthetic result is very low compared to tumor pathology with another location.1]. The close collaboration between the plastic surgeon and the ophthalmologist during the entire duration of the treatment is essential in order to obtain good and stable results over time [2].The treatment of patients with giant tumors located in the orbitofrontal region should be performed by multidisciplinary teams that include, besides the plastic surgeon, the ophthalmologist, neurosurgeon, pathologist, and oncologist. The necessity of performing the orbital exenteration greatly increases the difficulty of the surgical intervention, contributing equally to the increase of the overall time of the surgery, as well as of the rate of complications associated with it . Performing the intraoperative histopathological examination is essential for the good course of the treatment, the complexity of the subsequent surgical interventions depending largely on the dimensions of the postexcisional defect [4]. In situations in which the patient’s pathological personal history is favorable, performing the reconstruction of large soft tissue defects using free tissue transfer flaps is the best solution.The treatment of facial neoplasms extended in the intra-orbital structures is extremely complex, being tolerated by patients with difficulty, in the conditions in which ensuring oncological radicality often requires orbital exenteration [5]. The histopathological analysis is a fundamental element during the therapeutic protocol of neoplastic processes, establishing the surgical indications, the profile of the therapeutic protocol and the postoperative behavior [6]. The international scientific literature dedicated to understanding the particularities and evolution of giant basal cell carcinomas showed that these tumors express neuroactive mediators, also presenting an accelerated rate of cell multiplication [7].The histopathological examination of the giant tumors located in the fronto-orbital region showed that the cell typology was associated with the accelerated growth rate of the neoplastic processes, also having a significant impact on the postoperative prognosis [8].The frontal flap remains the main reconstructive option for soft tissue defects in the nasal region, especially in situations in which large radical excisions are performed [9]. In order to achieve this goal, the temporal muscle flap has proven to be a very good solution, ensuring the premise of rapid healing, with stable results over time.The reconstruction of the upper orbital region is extremely difficult in cases in which total excision of the soft tissue is required, with large areas of bone exposure. These situations require the reconstruction based on muscle and fascia flaps, the rich vascular supply being an essential element in accelerating the healing and integration processes of skin grafts [10]. The temporal fascial flap represents without a doubt a true “seat belt” in terms of reconstruction of the facial region in patients with giant tumors.The reconstruction of the orbital floor was performed with a temporal fascial flap, thus creating the premises for a rapid integration of the skin graft. This type of flap has the advantage of great flexibility, having the particularity of maintaining its viability even under very high degrees of rotation [11], because not infrequently, the initial therapeutic protocol is changed intraoperatively due to the neoplastic extension to the neighboring structures.Knowing in detail the remaining reconstructive resources following the excision is essential to cover the soft tissue defects of large dimensions. Regardless of the anatomical region involved, reconstructive options need to be analyzed from a wide perspective [12]. Giant tumors located at the level of the cephalic region are often associated with mutilating scarring [13]. The invasion of the orbital region by the neoplastic processes contributes in a significant manner to the outline of the mutilation nature of this pathology.The postoperative aesthetic aspect is an extremely important element that must be discussed in detail with the patient [14]. However, it should be mentioned that basal cell carcinoma is associated with an increased healing rate and consequently with a higher postoperative prognosis, compared to neoplastic pathology, such as squamocellular carcinoma or melanoma [15]. Regarding the presented case, the postoperative aesthetic result was considered satisfactory by the patient.Performing the orbital exenterations to ensure the radicality of the oncological treatment is the main factor that contributes to the decrease of the patients’ satisfaction regarding the postoperative aesthetic result [Ensuring the radical excision of the tumor is the main component that influences the therapeutic algorithm.Postexcisional reconstruction is more difficult as the size of the defect is larger. In these situations, the reconstructive protocol should include an overview of all available options and their possible associations.Performing complex reconstructions involving the use of the temporal muscle flap associated with the temporal fascial flap and the frontal flap is possible and ensures good and stable results over time.Conflict of interestThe authors declare no conflict of interest.All authors agree with the publication of this manuscript.This clinical investigation complies with the standards of the Ethics Committee of the “Bagdasar-Arseni” Clinical Emergency Hospital and adheres to the principles of the Declaration of Helsinki.The patient was informed and signed the informed consent to participate in this study.


Macroscopic fields such as electromagnetic, magnetohydrodynamic, acoustic or gravitational waves are usually described by classical wave equations with possible additional damping terms and coherent sources. The aim of this paper is to develop a complete macroscopic formalism including random/thermal sources, dissipation and random scattering of waves by environment. The proposed reduced state of the field combines averaged field with the two-point correlation function called single-particle density matrix. The evolution equation for the reduced state of the field is obtained by reduction of the generalized quasi-free dynamical semigroups describing irreversible evolution of bosonic quantum field and the definition of entropy for the reduced state of the field follows from the von Neumann entropy of quantum field states. The presented formalism can be applied, for example, to superradiance phenomena and allows unifying the Mueller and Jones calculi in polarization optics. It is generally believed that low frequency waves appearing in the macroscopic world such as various types of mechanical waves including acoustic ones, magnetohydrodynamic, radio-frequency electromagnetic or gravitational waves can be successfully described using classical wave equations with external sources . This isThe aim of this paper is to propose a novel approach to macroscopic description of fields based on the notions of single-particle density matrix and averaged field . This formalism allows computing all additive quantities including the entropy of the macroscopic field also introduced here. The definition of entropy involves maximum entropy principle applied to the von Neumann entropy of quantum field. A new family of quantum Markovian master equations is proposed, generalizing the previous framework of quasi-free quantum dynamical maps and semigroups ,3,4,5. IFirst Quantization interpretation, where the classical field is treated as a  quantum wave function of the corresponding (quasi)particle. The further step called Second Quantization allows describing irreversible processes in terms of Markovian Master Equations for density matrices acting of the corresponding bosonic Fock space. In the final step, we develop the reduced state of the field formalism and apply it to the case of thermal sources and polarization optics.To illustrate in the simplest way the quantum features of classical fields, we begin with the discussion of light polarization in terms of Stokes parameters and its quantum-mechanical interpretation. Then, we present a complete description of a quantum field in terms of modes and its In optics, polarized light can be described using the Jones calculus, while the partially polarized one is treated using Mueller calculus .Jones vector and contains both amplitudes and phases of two orthogonal components of the wave electric field. The relevant parameter is the normalization of the Jones vectorI, and, using quantum picture of light, to the averaged photon number N. All those interpretations of Stokes matrixStokes parameters and form a four-dimensional Stokes vectorConsider first a monochromatic plane wave of light propagating along Axis 3 in a Cartesian frame with the basis complete description of polarization state of the monochromatic light beam. This assumption lies behind the Mueller calculus, which describes the action of any linear optical device by Stokes anticipated that those parameters provide a Poincare sphere. Therefore, a classical mixed state of polarization corresponding to a partially or completely polarized monochromatic light beam with a given intensity should be described by a probability measure on the Poincare sphere. Hence, the set of all mixed states is an infinite-dimensional simplex of all probability measures on the Poincare sphere generated by extreme points—the Dirac measures concentrated on all points of the sphere. On the other hand, in Stokes formalism, any mixed state of polarization is given by the three-dimensional vector with the length smaller or equal to Bloch sphere. Therefore, one can say that Stokes was the first who discovered the quantum nature of light, but similarly to Columbus was not aware of the meaning of his discovery [Although the Stokes matrix/vector is constructed from classical correlations between components of the classical electric fields, the above completeness assumption is not consistent with the classical probabilistic scheme. Namely, by treating polarization as a classical dynamical variable, each fully polarized state of light satisfying the equality in Equation  with a fiscovery .Jones calculus.The equivalence mentioned above sheds a new light on the Jones and Mueller calculi, which are useful tools in polarization optics. Namely, using the well-known results from the quantum theory of open systems ,8,9, we Equation  is equivThe general Mueller map is completely positive but not trace preserving as The natural question, related to the thermodynamic properties of polarized light, is the definition of entropy for a monochromatic light beam with a given polarization state described by x is the position vector and k denotes a discrete index. The modes evolve in time according to the formulaIn this paper, we restrict ourselves to the classical field occupying a finite volume and hence described by the set of complex modes first-quantization modes, (1)(2)the classical energy of the field mode In the picture of From now on, we identify the classical field configuration represented by the linear superposition of modes with the corresponding vector in the Hilbert space of the first quantization. Therefore, the only mathematical difference between classical field and the first-quantization interpretation is the chosen normalization. In the first case, we normalize field to the given energy or intensity, while in the second case to one treating classical field as a wave function of a single particle.second-quantization formalism describes the quantum field in terms of bosonic Fock space The vacuum stateThe Fock space is spanned by the vectors obtained by application of all monomials in creation operators acting on the coherent state, which is a joint eigenvector of all annihilation operatorsFor any vector The coherent state can be explicitly written asThe coherent state lifting procedures applied to operators acting on the single-particle Hilbert space.In the following, we restrict ourselves to two classes of operators acting on the Fock space obtained by two different additive observable on the Fock space The single particle observable In particular, for the Hamiltonian, we havemultiplicative unitaryAny unitary operator The action of single-particle density matrixFor the non-interacting field with dynamics governed by linear field equations with possible external classical and coherent sources, the fundamental measurable quantities, such as energy, momentum and angular momentum are additive observables. Therefore, instead of the full density matrix Here, the trace The explicit form of a single-particle density matrix is given byaveraged fieldThe additional information about the phases of the field is contained in the correlation matrix given by the formulaThe definitions in Equations  and 20)20) implyreduced description in terms of the pair reduced state of the field contains sufficient information about the most important properties of the macroscopic field interacting with environment. The reduced state of field is called pure if The In phenomenological thermodynamics of equilibrium systems, entropy is a function of a macroscopic state, which is characterized by a small number of controlled external parameters and temperature. Already in this case we have a certain freedom in selecting those external parameters related to our ability of controlling the system. The situation is more complicated for non-equilibrium systems where, typically, thermodynamic parameters including temperature become position-dependent and their choice is determined by the relevant time-scales of local equilibration processes.free energyU is the internal energy, T is the temperature, and S is the entropy), which determines the amount of work extractable from the system. Obviously, both extractable work and entropy depend on the available means of control over the system.A similar problem appears when the notion of entropy is discussed within classical or quantum statistical mechanics. The proper choice of the definition depends on the selected level of complexity of our theoretical framework. This level is determined by the set of accessible observables of the system, which can be measured and/or controlled. Again, this choice is also related to relevant time-scales. Such “subjectivity” in the definition of entropy does not lead to any inconsistencies. Namely, the basic thermodynamical quantity with direct physical interpretation depending on entropy is the N identical particles in a finite volume.The complete microscopical and statistical description of the state of such system is given by the N-particle probability distribution To illustrate the problem of selection of complexity level, we consider the classical gas of The natural choice for the entropy of such state is the Gibbs expressionHowever, the typical means of control over the gas are based on additive observables which does not involve correlations between individual particles. Therefore, for practical purposes, the statistical description of gas in terms of marginal single-particle probability distribution Equation  in the cN-particle probability distributions with the same marginal Maximum Entropy Principle applied to the single-particle reduced description [Among the Equation  can be tcription .We follow the analogous reasoning for the case of macroscopic field described in terms of the reduced state of the field quasi-free state on the Fock space, generated by the additive observable Consider first the One can easily compute the reduced state of the field corresponding to the state in Equation  obtaininTo include also macroscopic coherence, one can apply the Weyl unitary transformation to produce the new stateThe reduced state of the field corresponding to the state in Equation  is now 36)) are rmalism) .In the absence of coherent source, the equations become decoupled. Notice that, only in the absence of random source Although this type of equations is quite frequently used, its applicability is limited to classical coherent sources, zero-temperature environment and the absence of random scattering.To illustrate the presented formalism of reduced kinetic equations for reduced states of the field (Equations  and 36)36)), we The reduced kinetic equations proposed above with possible nonlinear and time-dependent generalizations provide phenomenological tools to deal with macroscopic field interacting with an environment. There exist examples where special classes of the reduced kinetic equations can be derived from the underlying Hamiltonian models of the field interacting with the thermal bath and using appropriate approximations. The most popular approximation scheme combines Born, Markovian and secular ones and leads to the operators decoherence rateThe rates den Rule . The ranquations  and 36)γ↑(k),γ↓.Equations  and 41)41) can bsuperradiance conditionsuperradiance and can be studied for various physical implementations: from Hawking radiation of rotating black holes to ocean wave generation by wind [The quantum phenomenon of stimulated emission becomes particularly interesting for moving heat baths interacting with the macroscopic field. The case of rotating heat baths has been discussed in details in  where quEquation  intoVThe above inequality is a typical condition for shock wave generation, i.e., the velocity of the source must be higher than the critical velocity given by the phase velocity The method for reduced description of quantum field presented above can be applied to the polarization degrees of freedom in the case of linear optics devices. Namely, one can consider a light beam consisting of photons occupying the modes with a narrow band of frequencies around the central frequency q denotes the wave vectors of the beam modes, which are concentrated in the vicinity of the leading wave vector (i)(ii)(iii)Here, Equation  with theFrom the discussion in the previous sections, it follows that the reduced description of a quantum field involves also the averaged field as an observable object. For polarization of a light beam, this is a two-dimensional complex vector The equation of motion for the averaged Jones vector is decoupled from Equation , but condoubly contracting. In terms of the explicit representationIntegrating the equation of motion (Equation ) betweenS^′=Φ(S^)The Kraus decomposition in Equation  is not uSimilarly, the corresponding In the most general case, the only condition which connects The condition implies that the difference of two completely positive maps Mueller–Jones maps.Summarizing, in contrast to a general belief that Jones and Mueller calculi refer to physically different situations, we argue that the complete description of the polarization state of light beam needs a pair The set of Mueller–Jones maps form a semigroup with the composition of two elementsFinally, we can settle the question of entropy for polarization of a light beam using the definition in Equation , which nThe mathematically consistent formalism of reduced description of quantum fields presented in this paper has a potentially wide range of applications. It is rather surprising that quantum features, in particular quantum statistics, have such an influence on the macroscopic behavior of wave-like excitations. Even for such macroscopic objects such as ocean waves generated by wind or magnetohydrodynamic waves in stellar atmospheres, the stimulated emission processes characteristic for bosons may lead to various macroscopic phenomena such as superradiance or creation of shock waves. The description in the form of two mathematical objects—averaged field and population numbers —can be seen as a macroscopic manifestation of particle–wave duality in the quantum world. Namely, for coherent sources, zero temperature environment and absent random scattering, the description in terms of wave equations with sources and pure damping is sufficient. When random/thermal effects prevail, the averaged field tends rapidly to zero and kinetic equations for (quasi)particle population numbers govern the evolution of the relevant observables. This is clearly visible for the case of moving sources . When the source velocity approaches the critical value incoherent production of (quasi)particles rapidly grows. At this moment, the classical wave description breaks down, which is interpreted as the creation of shock waves. However, the full macroscopic formalism of the reduced state of the field is valid. The averaged field part becomes irrelevant and the physical phenomena are described by the dynamics of the single-particle density matrix. Such “wave–particle transition” in the modeling of physical phenomena may explain the physical origin of singularities in purely classical theories such as hydrodynamics or general relativity. One can speculate that in general relativity when velocities of matter approach the speed of light, classical field description breaks down and the kinetic equations for graviton gas should be applicable.


Following publication of the original article , the autThe Abstract of the PDF has since been corrected in the published article.The publisher apologizes for any inconvenience caused.


This paper reports on a qualitative study on the impact of marriage and civil partnerships for lesbian, gay and bisexual (LGB) couples. Drawing on data from 50 dyad interviews in the UK, US and Canada, the paper investigates the ways in which couples make sense of spirituality in the context of a stigmatised sexuality. For some, the task of arranging a wedding or civil partnership ceremony provided a powerful reminder of their exclusion from mainstream religious denominations. This sense of stigma  was also present in later life, when the lack of social esteem granted to same-sex relationships gave rise to a sense of disenfranchised grief . Whereas some participants tended to frame sexuality and spirituality as a kind of binary choice, others resisted this marginalisation from religious and spiritual activities, even if this meant finding a personal sense of spirituality beyond the confines of organised religion.


At the end of a very long life, older adults often experience a significant decline in cognitive function. However, there are older adults who have maintained high levels of cognition and physical health. The purpose of this symposium is to illuminate interdisciplinary findings of cognitive engagement with late-life benefits of cognitive functioning and physical health. Components of cognitive reserve include sociodemographic variables , psychosocial variables  and physical and genetic reserve . Based on three major research studies , we highlight important aspects of building cognitive reserve and the implications for cognitive and physical health. The first presentation evaluates the importance of work complexity as a predictor of cognitive and physical health among participants of the SONIC study. Multiple group analyses yielded strong associations of occupational complexity with cognitive functioning for men. The second presentation reports logistic regression findings from the HAAS including education, strength and genetic markers, as well as mental health and their relatedness to cognitive abilities and physical health. The final presentation evaluates a structural equation model from the GCS, highlighting the interrelationship of cognitive reserve components  with cognitive and physical health in very late life. We will summarize and integrate the findings for their theoretical and practical implications and provide future directions.


Social isolation and perceived loneliness are major issues as they may place older adults at greater risks for health problems. The objective status of social isolation and the subjective perception of loneliness may have distinct meanings, and their longitudinal reciprocal relationship remains unclear. The purposes of this study were to examine the reciprocal effects of social isolation and loneliness among U.S. adults aged 50 and above and to explore the moderating effect of solitary activities by using the data from three waves of the Health and Retirement Study (HRS) collected in the year 2008, 2012 and 2016. The index of social isolation was created by summing five commonly used indicators, including marital status, living arrangement, and three types of social contact. Loneliness was assessed by a summary score of 11 items. Solitary activities included 13 activities with limited or no social interaction. The results estimated by the cross-lagged effects model showed positive reciprocal relationship of social isolation and perceived loneliness across waves: respondents with a higher level of social isolation were predicted to have increased loneliness, and more perceived loneliness was significantly associated with a higher level of social isolation in the following waves. The results also indicated that solitary activity had a direct effect on decreasing loneliness. This study improves the understanding of reciprocal effects of social isolation and perceived loneliness over years and indicates that practice needs to address the issues of social isolation and perceived loneliness at the early stage and provide more opportunities of solitary activities.


Genetic heterogeneity is a well-recognized feature of hepatocellular carcinoma (HCC). The coexistence of multiple genetic alterations in the same HCC nodule contributes to explain why gene-targeted therapy has largely failed. Targeting of early genetic alterations could theoretically be a more effective therapeutic strategy preventing HCC. However, the failure of most targeted therapies has raised much perplexity regarding the role of genetic alterations in driving cancer as the main paradigm. Here, we discuss the methodological and conceptual limitations of targeting genetic alterations and their products that may explain the limited success of the novel mechanism-based drugs in the treatment of HCC. In light of these limitations and despite the era of the so-called “precision medicine,” prevention and early diagnosis of conditions predisposing to HCC remain the gold standard approach to prevent the development of this type of cancer. Finally, a paradigm shift to a more systemic approach to cancer is required to find optimal therapeutic solutions to treat this disease. In the last decade, numerous studies have provided several and accurate details on the genetic alterations associated with hepatocellular carcinoma (HCC). In particular, the familial genetic alterations responsible for the development of cirrhosis and associated with HCC formation have been entirely unraveled . MoreoveAs shown in Table Based on these considerations, we can assert that the pharmacological principles of potential therapeutic agents targeting genetic alterations have been probably based on the wrong paradigm . First, The failure of these therapeutic strategies reinforces the importance of conventional therapies , which used alone or in combination, remain the only widely accepted clinical treatments for HCC –27. TherAn entirely different approach to the cure of HCC could consist of the prevention of the disease through the identification and targeting of the early genetic alterations that anticipate the neoplastic transformation. Unfortunately, this strategy seems also not to succeed in the difficulty to target/correct familial genetic alteration and oncogenic mutations. In this contest, the HBV transgenic mouse model offers the opportunity to study the process of tumor initiation and progression related to the HBV infection , 31, andAnother important aspect regarding the development of new potential therapeutic agents against HCC that should be taken into account is the role of metabolic-induced modifications acting as environmental modifiers with the ability to influence a susceptible genetic or epigenetic background . In this


We report a case of volar fourth and fifth carpometacarpal (CMC) joint dislocation complicated by a hamate hook fracture. The CMC joint was reduced in a closed fashion and temporally fixed with Kirschner wires. Using intraoperative computed tomography, the displaced fracture of the hamate hook was reduced by open reduction and internal fixation and fixed with a screw. We suggest that this rare injury was caused by the over contraction of the flexor carpi ulnaris and avulsion force from the ligamentous structure around the pisiform, hamate, and metacarpal bones. Dislocation of the carpometacarpal (CMC) joint is a relatively rare injury, and volar dislocation of the CMC joint is less common than dorsal CMC joint dislocation. Nalebuff reported two types of volar dislocations of the fifth CMC joint: volar radial or volar ulnar, depending on the type of ruptured ligament . FracturA 60-year-old man fell from a staircase and landed on the floor with his right wrist hyperextended. He had no history of hand or wrist injury. He presented to the nearby clinic complaining of severe pain and swelling of the right hand. A diagnosis of fourth and fifth CMC joint dislocation was made by radiography Figures . Closed Dislocation of the CMC joint was performed by longitudinal traction under sedation. The patient underwent open reduction and internal fixation of the hamate hook and percutaneous fixation of the CMC joint on the following day. The surgery was performed under general anesthesia. Surgical exposure was achieved with a longitudinal skin incision made between the hamate hook and pisiform, which was prolonged proximally by a palmer crease in a zigzag fashion. Guyon's canal was released for the exposure and protection of the ulnar artery and nerve. The pisiform and hamate hook was identified. The fracture site of the hamate hook was located using a longitudinal incision of the palmar carpal ligament . It was Three months after the operation, CT revealed a gap of the fracture site at the hamate hook . HoweverSeveral studies have reported volar joint dislocation of the fifth CMC joint, mostly without accompanying fracture of the hamate hook , 3, 4. NIn our case, the exact mechanism of the hamate hook fracture associated with the volar dislocation of the fourth and fifth CMC joint was unclear; however, we suggest that this injury was an avulsion injury, based on previously published studies. Garcia-Elias et al. reported a hamate hook fracture with volar dislocation of the fifth CMC joint and pointed out that this injury was caused as an avulsion injury from the ligamentous structure around the pisiform . These aTo provide an anatomical and biomechanical background for this hypothesis, Pevny et al. showed that the pisohamate and pisometacarpal ligaments are much thicker and stronger than other soft-tissue attachments around the pisiform . Rayan eIn terms of treatment of hamate hook fractures, most injuries of this type, which are typically caused by repetitive microtrauma or blunt trauma to the palm of the hand from playing golf or baseball, are treated by hook excision. In the report by Gunther et al., the fracture was left untreated, resulting in nonunion without symptoms . AnotherIn our case, open reduction and internal fixation of the fractured hook was performed, taking into account the mechanism of this injury. In contrast to the usual type of hamate hook fracture, we noted a gap between the hook and body of the hamate. An intraoperative three-dimensional CT scan was helpful for obtaining anatomical reduction of the fracture site. The fracture resulted in nonunion, which may have been related to the initial displacement and residual instability around the hamate hook, since the HCS screw length did not exceed the more than half of the hamate body.This is the first report to describe volar dislocation of the fourth and fifth CMC dislocation with a hamate hook fracture and its relationship to the ligamentous structure around the hamate hook. Our case indicates the importance of traction force in the strategic treatment of this injury.


Chemical transformations by heterogeneous catalysis enabled fundamental research and chemical industry to support the technical development and stabilize the prosperity of the human community for – at least – the last hundred years. The Haber-Bosch process providing vast amounts of cheap ammonia and its importance for a wide spectrum of industrial branches might serve as a vivid example. Complex changes in the human society and the relation of the latter to nature, especially the protection of the environment, require the optimization of known and development of new chemical processes yielding the targeted products with minimal possible damage to the pristine nature.A deep understanding of the ongoing processes on the interface between the participating phases in heterogeneous catalysis results in optimized materials and enables the development of urgently needed new processes, e.g. in the context of renewable energy storage. In the simplest case, heterogeneous catalysis involves only three general steps – adsorption of the reactants, reaction of the adsorbed reactants and desorption of the products – all happening on the active sites located on the accessible surface of the catalysts. One of the key issues in understanding heterogeneous catalysis is, therefore, the question of the formation and atomic decoration of the active sites as well as the role of their electronic structure. The nucleus of active sites is often a transition metal. In the traditional catalytic processes, such active sites may be located on a catalytically non-active support or are indeed a part of the support, most commonly an oxide. The so-obtained catalyst is obviously very complex, one may take as an example the classical Cu/zinc oxide/aluminum oxide catalyst for the methanol synthesis. The understanding of the catalytic mechanism on an atomic-molecular level in such systems is strongly hindered simply by the large number of reactions and processes possible. The use of unsupported catalysts based on metallic alloys reduces the number of possible elementary processes on the surface. The large number of different atomic configurations on the surface due to the presence of extended solid solutions in alloys still does not allow for an easy development of more transparent and provable reaction mechanisms – especially when severe segregation of one of the components is occurring. A way out of this dilemma may be achieved employing intermetallic compounds as unsupported catalysts. Their ordered crystal structures are caused by the special bonding feature – a coexistence of two- and multi-center atomic interactions – and contain atomic arrangements markedly deviating from the closest packing patterns characteristic for alloys. For the same bonding reasons, the electronic structure of intermetallic compounds also differs strongly from the ones of elemental metals or their alloys. Thus, the use of intermetallic compounds as catalysts allows to influence both – geometrical and electronic – factors controlling the general steps of heterogeneous catalysis mentioned above. Further typical but not general advantages of the intermetallic compounds are their high thermodynamic stability , chemical resistivity, mechanic stability, etc., which may play a key role considering the practical manufacturing of heterogeneous catalysts.All this gives a rough idea about the huge research field of heterogeneous catalysis on intermetallic compounds. The special issue of Science and Technology of Advanced Materials offers to the reader current results obtained by research groups around the world on this topic.This Special Issue was initiated together with our honorable colleague – Professor An Pang Tsai from the Tohoku University in Sendai, Japan. Much to our regret, An Pang Tsai passed away during the work on this project. The Editors of the Special Issue and the authors of the included publications dedicate this work to the memory of An Pang Tsai.


This poster presents the results of an intervention study exploring how engagement in telemedicine at home affects chronic patients’ perceptions of usability and acceptability of the employed equipment, perceptions of its psychosocial impact, and intention of future use in the context of population aging. A purposively selected sample of 103 patients (mean age: 58 years) with chronic conditions (diabetes and/or hypertension) recruited in a community health center in Slovenia tested a home telemedicine system (TMS). After three months of utilization, an assessment of the relative importance of the usability and acceptance of TMS as factors influencing the patients’ self-reported psychosocial perception of TMS and intention of future use was performed based on a proposed structural equation model explaining these interdependencies. The results confirmed four of eight tested hypotheses. Notably, the intensity of TMS use was found to affect the evaluation of its usability, the perception of its psychosocial impact, and the intent of future use. Usability was found to be the main factor directly influencing acceptability, perception of psychosocial impact and intent for future use, whereas acceptability did not significantly affect either the perception of the psychosocial impact of TMS or the intent of future use.