bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of asymmetric dendrimers with controllable chromophore concentration and improved electro-optical performance
Authors: Xu Huajun , Fu Mingkai , Bo Shuhui , Liu Xinhou
Published: February 2016

In this work, we provided a simple work-up procedure to prepare a new kind of electro-optical dendrimer with an asymmetric configurationviaa Cu-(i) catalyzed Huisgen-reaction.
Ce3+ sensitized bright white light emission from colloidal Ln3+ doped CaF2 nanocrystals for the development of transparent nanocomposites
Authors: Adusumalli Venkata N. K. B. , Koppisetti Heramba V. S. R. M. , Mahalingam Venkataramanan
Published: February 2016

Intense white light emissions are observed from colloidal single component Ce3+/Ce3+/Ce3+/Ce3+-doped CaF2 nanocrystals and their transparent nanocomposites.
Simple broadband via‐free microstrip composite right and left hand transmission line
Authors: Shen Qiusheng
Published: February 2016

A novel simple broadband via‐free microstrip composite right and left hand transmission line (CRLH‐TL) is proposed by etching a straight‐line slot in the conductor of the microstrip line and an eight‐edge‐shaped slot on the ground below the straight‐line slot. The CRLH‐TL has the advantages of simple structure, smaller size, and wide left hand frequency band. The results show that the left hand frequency band of the CRLH microstrip transmission line is 4.91−6.09 GHz, and the left hand frequency bandwidth is 1180 MHz.
Broadband measurement of high permittivity at millimetre‐wave frequencies
Authors: Hong Y.‐P. , Salter M.J. , Lee D.‐J.
Published: February 2016

In this Letter, a method for the broadband measurement of complex permittivity using a quasi‐optical technique is presented. After calibration of the quasi‐optical system, the material under test is inserted into the system and S‐parameters are measured from 220 to 330 GHz using a vector network analyser. An extraction method is then applied to calculate the complex permittivity. The permittivity measurements are validated by comparing with a well‐established extraction method and the comparison shows good agreement.
Use of 1‐bit digital‐to‐analogue converters in massive MIMO systems
Authors: Guerreiro J. , Dinis R. , Montezuma P.
Published: February 2016

Massive multiple‐input multiple‐output (MIMO) systems are being proposed for next generation broadband wireless systems. However, as the complexity of implementation grows with the number of antenna elements, their feasibility is a challenging task. Consider very low complexity, 1‐bit digital‐to‐analogue converters (DACs) for the downlink of massive MIMO systems. The impact of the resultant severe non‐linear distortion effects is analysed when a low‐complexity maximum ratio transmission technique is employed for user separation. The non‐linear distortion levels decrease with the number of transmit antennas allowing good performance, even with 1‐bit DACs are shown.
Directional and omnidirectional edge enhancement based on radial Hilbert transform of Gabor filter
Authors: Wang Ke
Published: February 2016

A directional and omnidirectional edge enhancement method is proposed based on radial Hilbert transform (RHLT) of directional Gabor filter (DGF). A new transfer function is introduced to develop a new RHLT that can be rotated to enhance edges along the specified direction. Furthermore, to increase the edge response at the specified direction and suppress noise, DGF with the centre frequency being at the direct current component, is designed to be radial Hilbert transformed.
Ultra‐flat low material loss porous core THz waveguide with near zero flat dispersion
Authors: Ali S. , Ahmed N. , Aljunid S. , Ahmad B.
Published: February 2016

A near zero dispersion flattened porous core photonic crystal fibre having ultra‐flat low material loss suitable for terahertz (THz) transmission is represented. A novel type of geometrical structure of air hole position has been proposed in this design. Numerical analysis exhibits effective material loss (EML) of 0.03746 cm−1 at 1.0 THz operating frequency and a flat EML of 0.0398 cm−1 from 1.5 to 5.0 THz with absolute EML coefficient of ±0.000416 cm−1. The proposed waveguide shows near zero flat dispersion of 0.4 ± 0.042 ps/THz/cm in the frequency range from 1.25 to 5.0 THz.
Square slot antenna with two spiral slots loaded for broadband circular polarisation
Authors: Sadeghi P. , Nourinia J. , Ghobadi C.
Published: February 2016

A simple design of a broadband circularly polarised (CP) square slot antenna with two loaded spiral slots is proposed. The CP operation is realised by embedding a pair of inverted‐L‐shaped strips around two opposite corners of the square slot and can be markedly improved by loading two spiral slots in the ground plane. By using these modifications, the 3 dB axial ratio bandwidth (ARBW) of about 5 GHz, which is chiefly ascribed to the existence of two spiral slots and impedance bandwidth of larger than 111% are achieved. However, the overall size of the antenna is only 20 × 20 × 0.8 mm3, it covers wider ARBW than many of the designed slot antennas.
Compact photonic crystal integrated circuit for all‐optical logic operation
Authors: Xavier Susan Christina , Carolin B. Elizebeth , Kabilan Arunachalam P. , Johnson William
Published: February 2016

Photonic integrated circuits (PICs) will be pushed to electronic integrated circuits in the forthcoming decade because of its package density, interconnections, improved functionality and cost effectiveness. In this study, the authors propose a new configuration of photonic crystal (PhC) integrated circuits to realise the operation of all‐optical logic AND function that operates at a speed of hundreds of gigabits per second. The integrated circuit comprises of lasers, waveguide couplers, logic gate, amplifier and threshold limiter in a two‐dimensional (2D) silicon PhC platform. The behaviour of the proposed structure is qualitatively analysed by the use of 2D finite‐difference time‐domain method. The results show that the integrated circuit performs the required logic operation. The average area required for the entire device including regenerated circuit is 25 × 10 μm2. The overall response time is <2 ps. This device is one of the promising platforms for future optical computers and optical signal processor.
NMR studies of methane and hydrogen in microporous materials
Authors: Ji Yu , Hamida J. A. , Tang Yibing , Sullivan N. S.
Published: February 2016

We review the results of nuclear magnetic resonance studies of the molecular dynamics of the quantum gases HD and CH4 adsorbed in the cages of microporous structures. Measurements of the variation of the nuclear spin-lattice and nuclear spin-spin relaxation times with temperature provide detailed information about the translational and rotational dynamics of the adsorbed molecules over a wide temperature range.
Quantum effects in the sorption kinetics of 4He by mesoporous materials
Authors: Dolbin A. V. , Khlistyuck M. V. , Esel'son V. B. , Gavrilko V. G. , Vinnikov N. A. , Basnukaeva R. M. , Danchuk V. V.
Published: February 2016

Sorption and desorption of 4He by a mesoporous silicate material MCM-41 was studied in the temperature range of 1.5–290 K. It was shown that for T = 25–290 K the thermal activation mechanism is dominant in the sorption kinetics of 4He atoms by an MCM-41 sample. Its activation energy was estimated as Ea ≈ 164.8 K. For T = 12–23 K, the diffusion of 4He atoms in the MCM-41 was practically independent of temperature, which typically occurs when the tunnelling mechanism of diffusion dominates over the thermally activated one. A change in the mobility of 4He atoms in MCM-41 channels was observed at T = 6–12 K, which may be indicative of the formation upon cooling (or decay upon heating) of a 4He monolayer and subsequent multilayers on the inner surfaces of the channels. Below 6 K, the diffusion coefficients of 4He are only weakly temperature dependent, which may be attributed to the behavior of quantum 4He liquid in the MCM-41 channels covered with several layers of 4He atoms.
Magnetic phases and relaxation effects in fullerite C60
Authors: Chigvinadze J. G. , Buntar V. , Ashimov S. M. , Dolbin A. V.
Published: February 2016

A highly sensitive torsional vibration technique is used to study the magnetic properties of fullerite C60 (99.98%) at temperatures of 77–300 K in dynamic and static experiments. Vibrational energy absorption peaks associated with phase transitions and realignment of the magnetic structure of the fullerite are detected at T = 152, 195, 230, and 260 K. Relaxation magnetic processes in fullerite C60 at room temperature are studied. “Spontaneous” rotation of a motionless sample of fullerite freely suspended on an elastic filament is observed when external longitudinal or transverse magnetic fields are switched on. The direction of the “spontaneous” rotation changes with time. It is proposed that these phenomena are related to relaxation processes in the rotational subsystem of C60 molecular rotators, as well as to magnetic flux trapped in the fullerite and weakly damped eddy currents induced in the sample by the applied field.
Thermal fluid modeling of a passive heating system
Authors: Hami Khelifa , Draoui Belkacem , Imine Omar , Hami Omar
Published: February 2016

In this work, two-dimensional and three-dimensional simulations on the flow in a room coupled with a facade of passive heating system type In-In (Trombe wall) were conducted numerically to determine the temperature and velocity fields in the influence of the variation of the modified Rayleigh number, which itself depends on the characteristics of the fluid and heat flow due to sunshine. The behavior of boundary layers in natural convection is analyzed along the Trombe wall in our periodically heated imposed flow. Thermal and dynamics modeling of the problem were made by a computational fluid dynamics (CFD) calculation, based on the finite volume method to model both the fluid flow and heat transfer. To take account of the strong temperature gradient and velocity near the walls, we chose a structured tight mesh near the walls and a little wider mesh elsewhere. The results have shown that for Grh > 4 × 108, the flow regime is laminar, while for Grh > 109, the flow regime becomes turbulent.
X-ray studies of barium manganite Ba6Mn24O48 in the magnetic transition region
Authors: Legchenkova I. V. , Prokhvatilov A. I. , Stetsenko Yu. E. , Yagotintsev K. A.
Published: February 2016

X-ray studies of polycrystalline and pressure compacted barium manganite powder Ba6Mn24O48 were conducted at room and low temperatures. It was found that the compacting process that leads to the accumulation of macro- and microstress in the sample exerts a substantial amount of influence on the diffraction pattern. We obtained data for the temperature dependence of the lattice parameters a and c, as well as the linear thermal expansion coefficient in the basal plane of the tetragonal phase at temperatures 20–100 K. In the region of the magnetic phase transition temperature 45 K, we found an abnormal change in lattice parameter a and negative values for the linear thermal expansion coefficients αa. However, at the same time there were no singularities along the c(T) dependence. We suggest that one possible reason for this temperature behavior of the structural and thermal characteristics of barium manganite, is the significant anisotropy of the crystal lattice.
Dynamic line rating for wind power
Authors: Talpur Saifal , Wallnerström Carl Johan , Flood Christer , Hilber Patrik
Published: February 2016

Dynamic line rating is a novel technique used to determine the actual value of available power transmission capacity of overhead lines being underestimated by static line rating. Contrary to static line rating method, this approach provides huge technical and economic benefits of transmitting the electrical energy under controlled constraints. Nevertheless, it is of utmost importance to have an accurate knowledge of dynamic ampacity before being practically implemented. Owing to dynamic line rating technique, an overhead conductor is rated on the basis of real-time ampacity. Furthermore, the real time ampacity contributes in combating the growing power transmission demand being observed over highly congested power transmission network. Contrary to dynamic line rating approach, building new overhead lines is a lengthy, expensive, and less reliable option. Another important advantage offered by the dynamic line rating approach is to allow excessive renewable power generation in the electricity network, particularly the wind power due to its correlation with real-time ampacity. Besides, dynamic ampacity and wind power integration, the paper also deals with risk analysis associated with conductor overloading. The risk involves increase in conductor sag as it transmits the power beyond its nominal capacity at a certain temperature. However, in this paper, the dynamic as well as the static ampacity of “VL3” overhead conductor is calculated on the basis of its nominal temperature (50 °C) to avoid the risk of its possible expansion and ultimately the deterioration. In addition to technical analysis, the economic analysis of integrating a 60 MW wind park with Fortum's 130 kV regional grid and of applying dynamic line rating approach on a periodically overloaded “VL3” overhead conductor is thoroughly investigated in this research work; to further know how beneficial it is to temporarily postpone the rebuilding and/or construction of a new overhead line in parallel to the existing overhead conductor (VL3).
Enhanced stability of complementary resistance switching in the TiN/HfOx/TiN resistive random access memory device via interface engineering
Authors: Zhang H. Z. , Ang D. S. , Yew K. S. , Wang X. P.
Published: February 2016

This study shows that a majority (70%) of TiN/HfOx/TiN devices exhibit failed complementary resistance switching (CRS) after forming. In conjunction with the consistent observation of a large non-polar reset loop in the first post-forming voltage-sweep measurement, it is proposed that breakdown of the TiN/HfOx interfacial oxide layers (crucial in enabling CRS) and the accompanied formation of Ti filaments (due to Ti migration from the TiN cathode into the breakdown path) resulted in CRS failure and the observed non-polar reset behavior. This hypothesis is supported by the significant reduction or complete elimination of the large non-polar reset and CRS failure in devices with a thin Al2O3 layer incorporated at the TiN-cathode/HfOx or both TiN/HfOx interfaces. The higher breakdown field of the thin Al2O3 enables it to sustain the forming voltage until the forming process is interrupted, thus enabling CRS via oxygen exchange with the adjacent vacancy-type filament formed in the HfOx.
Optimum thickness of soft magnetic phase in FePt/FeCo permanent magnet superlattices with high energy product and large magnetic anisotropy energy
Authors: Jain Sandeep Kumar , Chittari Bheema Lingam , Kumar Vijay
Published: February 2016

Ab initio calculations on hard/soft (FePt)m/(FeCo)n, (m = 4, 6, 8 and n = 2-2m) magnetic superlattices show that the B2 type FeCo layers become anisotropic with varying interlayer spacing and enhanced magnetic moments. The average magnetic moment in superlattices is higher than in bulk FePt, resulting in high maximum energy product for (FePt)4/(FeCo)8 which is nearly double the calculated value for bulk FePt. The calculation of the magnetic anisotropy energy shows that the optimal thickness of the soft magnetic phase for good permanent magnet behaviour of the superlattice is less than ∼2 nm.
Reproductive biology and breeding system in Casuarina equisetifolia (Casuarinaceae) – implication for genetic improvement
Authors: Zhang Y. , Zhong C.L. , Han Q. , Jiang Q.B. , Chen Y. , Chen Z. , Pinyopusarerk K. , Bush D.
Published: February 2016

Understanding the reproductive biology of plant species is essential for successful domestication and genetic improvement programs. Casuarina equisetifolia L. is an important plantation species in China and India but information on reproductive biology is limited. To address this issue, grafted ramets of C. equisetifolia were used to study floral biology, breeding system and progeny performance. The female floral longevity of C. equisetifolia reached 28.4 days under non-pollination conditions, which was significantly longer than that of supplementary pollination (5.5 days) and open pollination (12.2 days), implying successful pollination would accelerate senescence of female flowers. Higher fruit set (88.8%) and seed set (35.7%) under supplementary pollination were obtained, compared with 75.9% and 21.7%, respectively, under open pollination, although there were no fruit set and seed set under non-pollination conditions. Pollen limitation was evident based on pollen limitation index (0.39) in seedling plantations of C. equisetifolia. Selfed seedlings had low height and diameter growth in both nursery and field trials and markedly lower survival in field trial, indicating inbreeding depression. Microsatellite-based estimates of selfing rate of open pollinated, monoecious individuals was 42%, suggesting that monoecious C. equisetifolia individuals are self-compatible, and that the breeding system should be classified as facultative xenogamy.
Stability, stasis and change
Authors: D'Arcy Alexandra
Published: February 2016

Intensification is prone to invention and renewal, rendering it ideal for delving into mechanisms of variation and change. Recycling (via lexical replacement) is a putative longitudinal constant, yet grammatical change (via grammaticalization) is regularly invoked in the literature. It is not clear how these complement each other. To probe this issue, this paper operationalizes variationist methods to examine intensification in the Origins of New Zealand English Corpus (ONZE; Gordon et al. 2007). The analysis draws on nearly 13,000 tokens across the longue durée (Braudel 1958, 1980), tracing intensification over 130 years of vernacular speech. The picture that emerges extends beyond the distributional waxing and waning of forms. There is evidence for lexical change, but the longitudinal trajectory is not always continuous. Replacement entails reorganization followed by leveling, and grammatical correlates shift across time. Nonetheless, the inherent form/function asymmetry that characterizes the sector also supports periods of ‘fevered’ change.
Venir de (+ infinitive)
Authors: Bres Jacques , Labeau Emmanuelle
Published: February 2016

This paper deals with the grammaticalisation of venir into an aspectual auxiliary of immediate anteriority, against the traditional approach (Gougenheim 1971 [1929]) according to which venir de + inf, would express recent past and so would be a temporal auxiliary. On the basis of the (revised) Reichenbachian model, it shows that venir de + inf bears upon the relationship between R and E (aspect) and not on the relationship between R and S (time). This analysis explains why venir, in this periphrasis, is defective (i.e., why venir cannot be conjugated in the passé simple or in any compound tense).
1. Peer interaction and learning
Authors: Fernández-Dobao Ana
Published: February 2016

This chapter investigated whether all learners benefitted from the lexical language-related episodes (LREs) produced in small group interaction, even when acting as silent observers of their peers’ collaborative work. Using a pretest-posttest design, evidence was obtained confirming that silent learners did benefit from LREs. In fact, they were almost as likely to gain new knowledge as those learners who triggered the episodes. These findings indicate that silent learners were as actively engaged with the vocabulary being discussed in the LREs as their speaking peers. Other factors, such as the length of the episode and the amount of negotiation and repetition, seemed to have a stronger influence on learning than the actual opportunities to speak. The pedagogical implications of these findings are discussed.
3. Interaction or collaboration? Group dynamics in the foreign language classroom
Authors: Sato Masatoshi , Viveros Paula
Published: February 2016

This chapter reports on a classroom-based quasi-experimental study examining the relationship between interactional moves and collaborative patterns in peer interaction and their effect on L2 development, using proficiency as an independent variable. Participants were from two parallel Grade 10 English classes in Chile, divided into low and high proficiency classes by the school (N = 53). A series of communicative group work activities were designed and implemented during the regular classes. L2 development was investigated by examining past tense usage and vocabulary size. Focus groups from the two classes (n = 10) were used for analyses of interactional features. Results indicated that learners in the low proficiency group (a) provided more corrective feedback and produced more modified output, (b) engaged in more collaborative interaction, and (c) exhibited a greater L2 development, than the high proficiency group. In order to interpret the results and conceptualize the links among interaction-­collaboration-learning, the findings are discussed in relation to a theory in social psychology referred to as social interdependence theory. It is concluded that while proficiency does have an impact on learners’ interactional behaviours, a collaborative mindset – a learner’s psychological approach towards the partner and/or task – may be a stronger mediating factor for L2 development.
11. Small-group meta-analytic talk and Spanish L2 development
Authors: Moranski Kara , Toth Paul D.
Published: February 2016

In this chapter, we examine the meta-analytic talk of nine adolescent L2 Spanish learners and their subsequent accuracy on a grammaticality judgment task, with the pronoun se as an instructional target. Data come from a U.S. high school during three 90-minute lessons, where learners “co-constructed” rules for se in groups based on its use in reading passages. We coded learners’ analytic talk as belonging to higher or lower levels of analytical abstraction (LAAs) to distinguish labeling L2 forms and categories from identifying broader patterns and rules. The amount of individual and group analytic talk, as well as talk at higher LAAs, was compared to individual grammaticality judgment scores before and six weeks after instruction. Results show that learners in groups with greater mutuality improved their scores even when their overall individual participation was only low or moderate. Implications for theory and practice are discussed.
An Experimental Test of Novel Ecological Communities of Imperiled and Invasive Species
Authors: Goodchild Shawn C. , Stockwell Craig A.
Published: February 2016

Imperiled fish species are often managed by establishing refuge populations as a hedge against extinction, but suitable sites are often at a premium. Thus, managers may wish to consider novel strategies, such as establishing multispecies refuges that already include undesirable species. To determine the suitability of multispecies refuges, we established experimental communities that included allopatric and sympatric communities of three fish species: the endangered Pahrump Poolfish Empetrichthys latos, the Amargosa Pupfish Cyprinodon nevadensis, and the invasive Western Mosquitofish Gambusia affinis. Mosquitofish juvenile production was not significantly affected by the presence of the other species (mean ± SE: 50 ± 18 in allopatry, 33 ± 6 with poolfish, and 38 ± 7 with both poolfish and pupfish). Similarly, pupfish persisted in sympatry with both poolfish and mosquitofish, but pupfish had higher juvenile production when maintained in allopatry (557 ± 248) and in the presence of poolfish (425 ± 36) than in the presence of both poolfish and mosquitofish (242 ± 32). By contrast, poolfish juvenile production was high in allopatry (123 ± 17) but significantly lower in the presence of pupfish (6.6 ± 1.2) and mosquitofish (1.0 ± 0.5) individually and in a community of all three species (0.5 ± 0.4). This suggests that translocated pupfish can coexist in refuges containing nonnative mosquitofish but that endangered poolfish are not compatible with the other species and the current management of poolfish in single‐species refuges is appropriate. Consequently, our results indicate that multispecies refuges are suitable for some endangered species, which will give managers more latitude in the management of these species.

Received March 30, 2015; accepted October 27, 2015
Critical Assessment 23: Gallium nitride-based visible light-emitting diodes
Authors: Oliver R. A.
Published: February 2016

Solid-state lighting based on light-emitting diodes (LEDs) is a technology with the potential to drastically reduce energy usage, made possible by the development of gallium nitride and its alloys. However, the nitride materials family exhibits high defect densities and, in the equilibrium wurtzite crystal phase, large piezo-electric and polarisation fields arising at polar interfaces. These unusual physical properties, coupled with a high degree of carrier localisation in devices emitting visible light, result in ongoing challenges in device development, such as efficiency ‘droop’ (the reduction in efficiency of nitride LEDs with increasing drive current density), the ‘green gap’ (the relatively low efficiency of green emitters in comparison to blue) and the challenge of driving down the cost of LED epitaxy.
Elevated pCO2 drives lower growth and yet increased calcification in the early life history of the cuttlefish Sepia officinalis (Mollusca: Cephalopoda)
Authors: Sigwart Julia D. , Lyons Gillian , Fink Artur , Gutowska Magdalena A. , Murray Darren , Melzner Frank , Houghton Jonathan D. R. , Hu Marian Yong-an
Published: February 2016

Ocean acidification is an escalating environmental issue and associated changes in the ocean carbonate system have implications for many calcifying organisms. The present study followed the growth of Sepia officinalis from early-stage embryos, through hatching, to 7-week-old juveniles. Responses of cuttlefish to elevated pCO2 (hypercapnia) were investigated to test the impacts of near-future and extreme ocean acidification conditions on growth, developmental time, oxygen consumption, and yolk utilization as proxies for individual fitness. We further examined gross morphological characteristics of the internal calcareous cuttlebone to determine whether embryonically secreted shell lamellae are impacted by environmental hypercapnia. Embryonic growth was reduced and hatching delayed under elevated pCO2, both at environmentally relevant levels (0.14 kPa pCO2 similar to predicted ocean conditions in 2100) and extreme conditions (0.40 kPa pCO2). Comparing various metrics from control and intermediate treatments generally showed no significant difference in experimental measurements. Yet, results from the high pCO2 treatment showed significant changes compared with controls and revealed a consistent general trend across the three treatment levels. The proportion of animal mass contributed by the cuttlebone increased in both elevated pCO2 treatments. Gross cuttlebone morphology was affected under such conditions and cuttlebones of hypercapnic individuals were proportionally shorter. Embryonic shell morphology was maintained consistently in all treatments, despite compounding hypercapnia in the perivitelline fluid; however, post-hatching, hypercapnic animals developed denser cuttlebone laminae in shorter cuttlebones. Juvenile cuttlefish in acidified environments thus experience lower growth and yet increased calcification of their internal shell. The results of this study support recent findings that early cuttlefish life stages are more vulnerable towards hypercapnia than juveniles and adults, which may have negative repercussions on the biological fitness of cuttlefish hatchlings in future oceans.
Cerebrovascular Emergencies
Authors: Schaefer Pamela W. , Roccatagliata Luca
Published: February 2016

Acute neurological impairment with a vascular etiology, or “stroke,” is frequently encountered in the emergency department. Acute ischemic stroke accounts for 87% of all strokes, while the remaining 13% of acute strokes are hemorrhagic. Hemorrhagic strokes include intraparenchymal hemorrhage (IPH) and subarachnoid hemorrhage (SAH). This chapter describes imaging findings, clinical features, anatomy and physiology, and current treatment options for acute ischemic stroke, IPH, and SAH. Practical, evidence-based, algorithms are given that allow imaging of brain parenchyma, subarachnoid spaces, and cerebral vasculature. Entities that mimic hemorrhagic and ischemic stroke and their key differentiating features are presented.
Pulmonary Infections
Authors: Marone Louis , Hayim Morris , Lo Hao S. , Abujudeh Hani H.
Published: February 2016

Pulmonary infections are among the most common disorders seen in the emergency room setting. Infections can be generally classified as those involving the airways, tracheobronchitis for the central and bronchiolitis for the smaller airways, and pneumonia for the lung parenchyma. In the United States, pneumonia is the ninth leading cause of death and the number one cause of death from infection. Worldwide, lower respiratory tract infections cause 3.9 million deaths per year, 1.8 million of which occur in children under five years of age.
Solid Organ Injury
Authors: Bryan Roy G. , Abujudeh Hani H. , Ganguli Suvranu
Published: February 2016

This chapter on solid organ injury covers the commonly encountered radiological emergencies of splenic, liver, and renal trauma. Solid organ injury includes a broad group of life-threatening entities involving the intra-abdominal organs that occur in the setting of blunt or penetrating abdominal trauma. We discuss the role of the consulting radiologist in abdominal trauma, including the keys to making the diagnosis of solid organ injury with multimodality imaging, as well as the differential diagnoses, grading of injury, and potential treatment options. Case examples provided in the chapter include a Segment VII liver laceration with hemoperitoneum, splenic laceration with pseudoaneurysm, and renal trauma with arteriovenous fistula formation.
Emergent Evaluation of Acute Liver Failure
Authors: Mirzan S. Hamad , Mansouri Mohammad , Abujudeh Hani H.
Published: February 2016

Acute hepatic failure is a serious, life-threatening condition, usually afflicting patients without a prior history of hepatic dysfunction. The most common causes of hepatic failure are viral- and drug-induced. Other less common causes include vascular causes such as hepatic vein thrombosis. Hepatic failure from hepatic dysfunction has a high rate of mortality. Patients often have abnormal liver biochemical markers with elevated bilirubin and aminotransferase levels. Coagulopathy and unexplained bleeding can occur as the prothrombin time (PT) is prolonged. As the hepatic dysfunction progresses, other clinical manifestations, including encephalopathy, may develop.
Traumatic Injury of the Duodenum and Pancreas
Authors: Shaqdan Khalid , Nicola Refky , Shaqdan Ayman , Abujudeh Hani H.
Published: February 2016

Traumatic injuries of the pancreas and duodenum are particularly challenging to radiologists despite the many advancements in technology and abdominal imaging. Acute pancreatic injuries occur in 0.2% of patients with blunt trauma, and in 1-12% of patients with penetrating injuries, while penetrating injuries have become the leading cause for duodenal injuries in the United States, with gunshot wounds representing 75-80% of cases. Both pancreatic and duodenal injuries are lethal injuries, with mortality rates varying from 9-34% and 6-25%, respectively. Most pancreatic and duodenal injuries are managed operatively and have good outcomes if they are recognized as early as possible. A delayed diagnosis can have serious consequences.
Trauma of the Lower Urinary Tract
Authors: Cruz-Romero Cinthia
Published: February 2016

Bladder ruptures are a result of blunt or penetrating trauma. The probability of bladder injury increases with the degree of distention: a full bladder will rupture without the application of a great force or pelvic fracture. Bladder rupture is almost always accompanied by hematuria. According to extravasation, ruptures can be extra- or intra-peritoneal. Extra-peritoneal rupture is nearly always associated with pelvic fractures and constitutes the majority of the ruptures. Intra-peritoneal ruptures occur when the bladder is distended, causing blowout of the dome. A CT cystogram after secure urethrogram should be performed when there are pelvic fractures, gross hematuria, free pelvic fluid, or pelvic hematoma of unknown source. Recognizing the patterns of contrast extravasation is crucial for diagnosis and treatment; therefore, the bladder should be sufficiently distended. Management of intra-peritoneal bladder ruptures is surgical, whereas extra-peritoneal ruptures can be managed emergencies.
Pediatric Abdominal Emergencies
Authors: Phewplung Teerasak , Shailam Randheer
Published: February 2016

Emergencies in the pediatric abdomen can present at any age, including during the neonatal and infant periods. Several diseases in older children and adolescents have similar clinical presentations as in adults. In this chapter we review select abdominal emergencies in the newborn and young children. Obstructions along the course of the gastrointestinal tract from the esophagus to the anus can be a cause of vomiting and pain. Some of these may be congenital, developmental, or acquired. Often diseases in neonates and young children are different than in adults, and it may be challenging for radiologists to recognize and accurately diagnose pathologies that are widely ranging from benign to life-threatening conditions. Accurate diagnosis and prompt treatment are crucial.
Dual Energy Computed Tomography in Emergency Radiology
Authors: Mansouri Mohammad , Aran Shima , Abujudeh Hani H.
Published: February 2016

DECT is capable of differentiating materials with different atomic numbers and electron densities with data gathered from two different spectra. Different materials with similar coefficient attenuation can be distinguishable at different energy levels used. DECT is mainly based on how substances behave at different energy levels. The additional capabilities of DECT are obtained without an increase in patient’s radiation dose. With the recently available technologies, simultaneous datasets are achieved using various types and rotations of tubes, detector arrays, and fan beams energy.
Volvulus
Authors: Hassanzadeh Elmira , Nicola Refky , Aran Shima , Abujudeh Hani H.
Published: February 2016

Volvulus is defined as the twisting of small or large bowel around its mesenteric axis. This can cause varying degrees of obstruction as well as severe vascular compromise. -Chronic constipation and obtundation from narcotics or other medications can cause gaseous distention of the abdomen. The most frequent locations within the abdomen are sigmoid colon and cecum, because they are the most mobile segments of the colon. However, a volvulus of the stomach can also occur. An even less common volvulus is in the small bowel, which is called a closed-loop obstruction, caused by an abnormal rotation of the small bowel along its mesenteric axis; thus an obstruction occurs at two points. As a result of the volvulus, torsion and occlusion of mesenteric vessels will result in ischemia and necrosis. Therefore, this is considered a surgical emergency because the mortality is between 10-35%.
Drugs in anaesthesia and intensive care, A–Z
Authors: Scarth Edward , Smith Susan
Published: February 2016

This chapter includes drugs beginning with the letter A, including A2RAs, ACE inhibitors, acetazolamide, aciclovir, adenosine, adrenaline, alfentanil, allopurinol, amiloride, aminoglycosides, aminophylline, amiodarone, amitriptyline, amoxicillin, amphotericin, aspirin, atenolol, atracurium, and atropine.
D
Authors: Scarth Edward , Smith Susan
Published: February 2016

This chapter includes drugs beginning with the letter D, including dabigatran , dantrolene, desflurane, dexamethasone, dexmedetomidine, dextrans, diamorphine, diazepam, diclofenac, digoxin, diltiazem, dobutamine, domperidone, dopamine, dopexamine, doxapram, and droperidol.
E
Authors: Scarth Edward , Smith Susan
Published: February 2016

This chapter includes drugs beginning with the letter E, including edrophonium, enflurane, enoximone, ephedrine, epoprostenol, eptacog alfa, erythropoietin, esmolol, ether, and etomidate.
G
Authors: Scarth Edward , Smith Susan
Published: February 2016

This chapter includes drugs beginning with the letter G, including gabapentin, gelatins, glucagon, glucose, glyceryl trinitrate, and glycopyrronium bromide.
H
Authors: Scarth Edward , Smith Susan
Published: February 2016

This chapter includes drugs beginning with the letter H, including haloperidol, halothane, Hartmann’s solution, heparins, human albumin solution, hydralazine, hydrocortisone, and hyoscine.
M
Authors: Scarth Edward , Smith Susan
Published: February 2016

This chapter includes drugs beginning with the letter M, including macrolides, magnesium, mannitol, metaraminol, metformin, methohexital, methoxamine, methyldopa, methylphenidate, metoclopramide, metronidazole, midazolam, milrinone, mivacurium, and morphine.
S
Authors: Scarth Edward , Smith Susan
Published: February 2016

This chapter includes drugs beginning with the letter S, including salbutamol, sevoflurane, sodium bicarbonate, sodium chloride, sodium nitroprusside, sodium valproate, spironolactone, SSRIs, statins, sucralfate, sufentanil, sugammadex, sulfonylureas, and suxamethonium.
W
Authors: Scarth Edward , Smith Susan
Published: February 2016

This chapter includes drugs beginning with the letter W, including warfarin.
X
Authors: Scarth Edward , Smith Susan
Published: February 2016

This chapter includes drugs beginning with the letter X, including xenon.
Haemodialysis
Authors: Levy Jeremy , Brown Edwina , Lawrence Anastasia
Published: February 2016

This chapter covers all aspects of haemodialysis from equipment, technical details, dialysates, and dialysis access from fistulas to lines and their complications and management; complications of dialysis ranging from hypotension to dialyser reactions, measuring dialysis adequacy, anticoagulation, prescriptions of chronic dialysis, and dry weight. It also discusses haemodialysis in various situations from peri-operatively to terminal care.
Home and frequent haemodialysis
Authors: Levy Jeremy , Brown Edwina , Lawrence Anastasia
Published: February 2016

This chapter describes the benefits of home dialysis, different approaches for home and frequent dialysis, including nocturnal and in-centre frequent dialysis, the new technologies associated with home dialysis, monitoring, environmental issues, nursing patients on home dialysis, and the education and training needed.
Nutrition on dialysis
Authors: Levy Jeremy , Brown Edwina , Lawrence Anastasia , Johansson Lina
Published: February 2016

This chapter describes how to assess, monitor, and measure aspects of nutrition in patients on dialysis, causes and recognition of malnutrition, nutritional requirements for patients on different modalities of dialysis, detailed strategies for achieving nutritional aims for potassium, protein, phosphate, energy, trace elements and vitamins, managing fluid requirements, and nutrition in patients with acute kidney injury. It also discusses aspects of parenteral nutrition and intradialytic parenteral nutrition, carnitine and other strategies.
Complications of ESKD: cardiovascular disease
Authors: Levy Jeremy , Brown Edwina , Lawrence Anastasia
Published: February 2016

This chapter describes the various forms of cardiovascular disease common in patients with end-stage renal disease and risk factors. It covers management of ischaemic heart disease in patients on dialysis, acute coronary syndromes, and the management of both cardiac and renal issues, hypertension, and its control in all forms of renal replacement therapy, cerebrovascular disease, and peripheral vascular disease in patients with end-stage renal disease.
Symptoms related to ESKD
Authors: Levy Jeremy , Brown Edwina , Lawrence Anastasia
Published: February 2016

Sections in this chapter discuss management of multiple symptoms in patients with end-stage kidney disease including fatigue, pruritus, pain, sleep disorders, restless legs, anorexia, constipation, nausea and vomiting, cramps, fluid overload, and oedema. Management strategies and treatments are included for all these symptoms.
Transplantation for dialysis patients
Authors: Levy Jeremy , Brown Edwina , Lawrence Anastasia
Published: February 2016

This chapter describes issues related to dialysis for patients undergoing renal transplantation including the assessment of patients prior to transplant, pre-transplant management, aspects of the transplant operation itself and the management of dialysis around this, management of patients acutely after a transplant, and dialysis in patient with delayed graft function
The Role of Cytotoxic Chemotherapy in Melanoma
Authors: Daud Adil , Ashworth Michelle
Published: February 2016

Advanced (unresectable stage III, metastatic stage IV) melanoma is often described as being resistant to cytotoxic chemotherapy, with low objective response (complete response + partial response) rates across regimens in various melanoma subtypes (cutaneous, mucosal, or uveal). As a result, chemotherapy in such cases has been largely palliative. Occasionally, however, a complete response occurs, or a deep partial response can be followed by metastectomy and lead to prolonged disease-free survival. This chapter focuses largely on the response rate and overall survival benefit offered by selected regimens, provides a brief historic overview of regimens evaluated in advanced melanoma, and concludes with a discussion of regimens commonly in use today.
Meniscus transplantation in skeletally immature patients
Authors: Kocher Mininder S. , Tepolt Frances A. , Vavken Patrick
Published: February 2016

Meniscal pathology in skeletally immature patients includes meniscal tears and discoid lateral meniscus. Total or subtotal meniscectomy may occur in patients with discoid lateral meniscus or severe meniscal tears. Meniscal transplantation may be an option in skeletally immature patients status after total or subtotal meniscectomy with knee symptoms or dysfunction. This study focuses on the surgical technique and short-term outcomes of meniscus transplantation in skeletally immature patients. We reviewed our clinical database for skeletally immature patients who had undergone meniscus transplantation with a minimum of 2 years of follow-up. Patients were contacted, invited for a physical exam, and asked to complete a Pedi-IKDC, Lysholm, and Tegner outcomes questionnaire. The study protocol was approved by the responsible institutional review board. Three patients (two females/one male) were eligible for the study, each of whom responded to our invitation indicating availability for physical exam and questionnaire. Two patients had undergone subtotal discoid meniscus resection, leading to early lateral compartment degeneration. One patient developed advanced degeneration after a delay in treatment for a medial bucket-handle tear associated with anterior cruciate ligament rupture. The mean age of the patients at the time of surgery was 12.6±2.3 years. At a mean follow-up of 31±20 months, the mean Pedi-IKDC score was 68.3±4, the mean Lysholm was 55.7±22.3, and the median Tegner was 7 points. There were no indications of growth deformity during the regular postoperative radiological assessments. One patient required subsequent lysis of adhesions along the lateral mini arthrotomy and mobilization under anesthesia. The other two patients were able to return to sports at the same level as before meniscus transplantation and were able to do so within 9 months postoperatively. Over-resection of discoid menisci as well as untreated meniscus injury, the latter typically in conjunction with ligamentous instability, can lead to advanced cartilage degeneration and recalcitrant complaints necessitating surgical treatment before skeletal maturity. We were able to show that meniscus transplantation in skeletally immature patients leads to acceptable clinical outcomes without growth deviation. Level of Evidence: IV.
Changes in Sexual Activity in Male Patients Surgically Treated for Kyphosis due to Ankylosing Spondylitis
Authors: Yao Ziming , Du Jianwei , Wang Zheng , Zheng Guoquan , Zhang Xuesong , Cui Geng , Wang Yan
Published: February 2016

Study Design.

A retrospective study.

Objective.

The aim of this study was to assess the changes in sexual activities in male patients surgically treated for ankylosing spondylitis (AS)-induced kyphosis and the correlation between these changes and spinal sagittal realignment.

Summary of Background Data.

Sexual function may be affected by AS. However, little is known about the effect of spinal surgery on the sexual activity of patients with AS-induced kyphosis.

Methods.

Data of 45 male patients who had been surgically treated for AS-induced kyphosis were retrospectively reviewed. Changes in sexual activity were evaluated by the international index of erectile function (IIEF), frequency of sexual activity, and time point at which sexual activity began postoperatively. We compared the above-mentioned parameters before and 24 months postoperatively and analyzed the correlation of the changes in the IIEF with the changes in radiological characteristics.

Results.

Each domain of the IIEF and the total IIEF were increased postoperatively. Improved sexual function was correlated with changes in spinal sagittal characteristics, among which lumbar lordosis (LL) and the chin-brow vertical angle (CBVA) were the most significant causes (P < 0.05). Most patients (71.1%) resumed their sexual activity 5 to 12 weeks after surgery. At the 24-month follow-up, the frequency of patients’ sexual activity was higher than that before surgery (P < 0.05).

Conclusion.

Surgical correction of spinal deformity may improve sexual function and increase the frequency of sexual activity in men with AS. Spinal sagittal realignment and pelvic rotation may be correlated with improvement of sexual function.

Level of Evidence: 4
Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio as Novel Biomarkers of Primary Open-Angle Glaucoma
Authors: Ozgonul Cem , Sertoglu Erdim , Mumcuoglu Tarkan , Kucukevcilioglu Murat
Published: February 2016

Purpose:

We aimed to assess the levels of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in patients with primary open-angle glaucoma (POAG) and to compare the NLR and PLR results of patients with POAG and ocular hypertension, as well as in healthy controls.

Patients and Methods:

Eighty-four patients with POAG, 94 patients with ocular hypertension, and 80 healthy subjects were enrolled in this retrospective study. Complete ophthalmological examination and complete blood count measurements were performed for all subjects.

Results:

There was a significant difference in the NLR (P=0.003) and PLR (P=0.049) between POAG and control groups. In addition, there was a correlation between pattern standard deviation and NLR in the POAG group. The receiver operating characteristics analysis revealed that the value of NLR to distinguish patients with POAG and controls was found to be 0.651. The best cutoff value was 2.1, with a sensitivity of 65% and a specificity of 65%.

Conclusions:

Our study for the first time provides evidence that NLR and PLR may be useful as biomarkers in patients with POAG.