bluuebunny/crossref_metadata_2025 huggingface dataset:
Pumped‐storage power generation system based on wave energy
Authors: Zhang Shao‐Qian , Zhu Yong‐Qiang
Published: January 2018

Ocean wave energy is a new type of pollution‐free renewable energy, and there are many kinds of wave energy utilising equipments designed recently. The magnitude of wave energy has the characteristics of time variation, so that the output of most wave power generation devices may not be directly integrated into the grid. In order to simplify the structure of the wave energy power generation system, reduce the design and manufacturing costs and improve the stability of the output to satisfy the grid‐connection control requirements of wave energy power generation, a wave energy conversion device is designed, which is convenient to maintenance and replacement, and a pumped‐storage power generation system based on this device is proposed. In this study, the design of wave energy pumped‐storage power generation system is explained in detail. The working condition of the device under different sea conditions is simulated, and the operating characteristics and reasonable parameters of the system are deduced. Theoretical analysis and simulation results can provide theoretical basis for the design of wave energy pumped‐storage power generation device and provide reference for engineering application.
Fault recovery for distribution network with distributed generation
Authors: Ba Wei , Yan Yuming , Wang Kangda , Wu Bingqing , Chen Zhenghong , Wang Xueying
Published: January 2018

Distributed generation (DG) has been largely used in distribution network in recent years, which brings more security, reliability, and economy, but some bad effects to the distribution network. In this study, recovering more loads, less switching actions and distribution network power loss are considered to establish the mathematical model of fault recovery in distribution network with DG. The particle swarm optimisation algorithm is used to solve the problem, and the fault recovery strategy is obtained. Besides, the impact of DG location on the fault recovery of distribution network is studied, and the simulation results show that when the DG is located dispersedly in the downstream of the distribution network, the distribution network recovery is in good condition. The results of this study provide a reference for the DG configuration of the distribution network.
Research of active load regulation method for distribution network considering distributed photovoltaic and electric vehicles
Authors: Fang Yaqi , Li Rui , Wang Linong , Song Bin , Li Enwen , Zhang Qiushi
Published: January 2018

In order to solve the problem of three‐phase unbalance in low‐voltage distribution network caused by large‐scale access of distributed photovoltaic (PV) and electric vehicles (EVs), an active load control method of three‐phase unbalance in distribution network was presented in this study. Firstly, the active load regulation system was established and its implementation scheme was detailed. Then the active load regulation strategy using an integrated multi‐objective optimisation control algorithm was put forward and a solution method based on improved genetic algorithm was also proposed to realise optimal load distribution. Finally, the validity and feasibility of the proposed strategy was verified by simulation and the simulation results show that the active load regulation strategy can improve the consumptive ability of distributed PV and EVs, and can effectively reduce the three‐phase unbalance degree to improve the quality of power supply.
Shell circulating current and transient ground potential rise in 220 kV GIS
Authors: Chen Taiyu , Liu Hongshun , Hu Dongyang , Liu Xinghua , Xu Tianxi , Yang Xiaoshuai , Ji Liang
Published: January 2018

In recent years, gas‐insulated switchgear (GIS) become more and more important in the power grid. The distance between GIS shell and its internal conductor is short, which cause a strong electromagnetic coupling between these two parts. A travelling wave will occurred when the GIS isolating switch and circuit breakers are closed or broken down, which will cause a high‐frequency oscillation electrical signal called very fast transient voltage, and finally lead to GIS shell circulating current and transient ground potential rise (TGPR). The principle of partial electric equivalent circuit (PEEC) method is briefly introduced here, and an equivalent circuit of GIS metal shell, bus conductor, and grounding grid is built according to the PEEC method. Based on the model of GIS shell and grounding circulating current, the theoretical calculations of the shell and grounding circulating current are taken by using the ATP‐EMTP simulation software. According to the result, the possible influencing factors of shell circulating current and TGPR are analysed, and some reasonable control measures are proposed.
Modelling and optimisation of residential electricity consumption considering energy storage and elastic electrical equipment
Authors: Sun Xin , Xue Jincheng , Han Ming Xu
Published: January 2018

With the progress of science and technology, residents’ electrical equipment has become increasingly intelligent. How to optimise the electricity consumption of residents’ intelligent equipment, has become the hotspot of current power system research. Firstly, classification and modelling of the electrical equipment including electric vehicle and photovoltaic with battery, elastic electrical equipment, and non‐elastic electrical equipment are carried out. Secondly, based on the time‐of‐use (TOU) price and introducing utility theory, the cost model and the utility function are established. On this basis, a residential power optimisation strategy is proposed. Finally, through the simulation analysis of typical residents’ electricity consumption situation, it is proved that the model can effectively reduce the electricity payment and improve the utility of the residents.
Combined time‐varying forecast based on the proper scoring approach for wind power generation
Authors: Chen Xingying , Jiang Yu , Yu Kun , Liao Yingchen , Xie Jun , Wu Qiuwei
Published: January 2018

Compared with traditional point forecasts, combined forecast have been proposed as an effective method to provide more accurate forecasts than individual model. However, the literature and research focus on wind‐power combined forecasts are relatively limited. Here, based on forecasting error distribution, a proper scoring approach is applied to combine plausible models to form an overall time‐varying model for the next day forecasts, rather than weights‐based combination. To validate the effectiveness of the proposed method, real data of 3 years were used for testing. Simulation results demonstrate that the proposed method improves the accuracy of overall forecasts, even compared with a numerical weather prediction.
Facile synthesis and photocatalytic performance of flower‐like Ag/ZnO nanocomposites
Authors: Cai Honglan , Qiao Qingan , Ren Shuhua , Zhu Dongdong , Xue Zhongxin
Published: January 2018

Flower‐like Ag/ZnO nanocomposites were successfully synthesised by a facile solvothermal method. The product was characterised by X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet‐visible diffuse reflectance spectroscopy and photoluminescence (PL) spectroscopy. It was found that ZnO was in the wurtzite phase and the Ag metal particles were loaded on the surface of the ZnO nanosheet. Compared with pure ZnO, the Ag/ZnO nanocomposite displayed significantly visible‐light absorption, reduced PL emission intensity, and enhanced photocatalytic activity for the degradation of Rhodamine B, which could be attributed to an effective separation of the photo‐generated electron–hole pairs in the nanocomposite.
Ambient-Pressure Asymmetric Preparation of S,S-DICHED, a C
2-Symmetrical Director for Matteson Reactions
Authors: Hirschhäuser Christoph , Bojaryn Kevin , Hoffmann Chris , Struth Felix
Published: January 2018

A synthesis of S,S-DICHED (dicyclohexylethane-1,2-diol), a C
2-symmetrical chiral director for Matteson homologations, is described. It relies on the insertion of lithiated S-2-cyclohexyloxirane into cyclohexylboronic acid pinacol ester and proceeds in three linear steps from readily available starting materials. No step requires chromatography or any specialized equipment.
Damiana
Authors: Bauer Rudolf
Published: January 2018

Damiana (Turnera diffusa) ist eine alte Arzneipflanze, die bereits von den Maya nicht nur gegen Asthma, sondern auch als Aphrodisiakum verwendet wurde. In Mexiko und verschiedenen anderen mittel- und südamerikanischen Ländern werden die Blätter auch heute noch gegen Muskelschwäche, als Tonikum, bei gastrointestinalen Beschwerden, Diabetes, Ödemen, Malaria und Hautkrankheiten, aber vor allem auch als Aphrodisiakum verwendet.

Die phytochemischen Untersuchungen der Inhaltsstoffe ergaben, dass die Blätter Flavonoide (u. a. Acacetin und Apigenin), viele Terpene (ätherisches Öl), Phenolglykoside (Arbutin), cyanogene Glykoside (u. a. Tetraphyllin B) sowie Gerbstoffe und Koffein enthalten.

Pharmakologische Untersuchungen zeigten neben einer angstlösenden, einer dosisabhängig schmerzlindernden und einer spasmolytischen Wirkung auch eine aphrodisierende Wirkung, und in vitro eine leichte Östrogenwirkung sowie eine Hemmung der Aromatase. Letztere hat eine verringerte Östrogenproduktion und einen erhöhten Testosteronlevel zur Folge, was einige Effekte der traditionellen Anwendung als Aphrodisiakum erklären könnte, da durch die Erhöhung des Testosteronspiegels das sexuelle Verlangen zunehmen kann.

Die bisherigen Studien, erfahrungsheilkundlichen Erkenntnisse und traditionellen Anwendungen von Damiana deuten auf ein hohes Potenzial der Heilpflanze im Hinblick auf ihre aphrodisierenden, antibakteriellen und anxiolytischen Eigenschaften hin. Weitere Forschungsarbeiten sind jedoch notwendig, um diese Tendenzen zu belegen.
Phytotherapie bei rheumatoider Arthritis
Authors: Schröder Dorit , Langhorst Jost
Published: January 2018

Komplementäre Therapieverfahren erfreuen sich in der Bevölkerung einer wachsenden Beliebtheit und werden auch von Patienten mit rheumatoider Arthritis nachgefragt. Ein wichtiges Thema stellen in diesem Zusammenhang pflanzliche Heilmittel dar: Viele Phytotherapeutika sind in der Apotheke frei verkäuflich und werden von Patienten zur Linderung ihrer rheumatischen Beschwerden eingesetzt; wissenschaftliche Wirksamkeitsnachweise fehlen jedoch häufig.
Modular portable unit for thermal conductivity measurements in multiple cryogenic/magnetic field environments
Authors: Tanatar M. A. , Bondarenko V. A. , Timmons E. I. , Prozorov R.
Published: January 2018

A modular design for a miniature thermal conductivity cell suitable for a dilution refrigerator and other sample-in-vacuum cryogenic environments with different magnet options is described. The sample is mounted once and the contacts remain in place when the unit is repositioned or transported between different magnets and cryostats. This mobility enables comprehensive measurements with access to specific options, such as vector magnet in one lab and ultra-high field in another. This design enables significant expansion of the temperature range by using not only dilution refrigerators but also 3He, 4He cryostats and even ubiquitous Quantum Design Physical Property Measurement System.
Direct intensity calibration of X-ray grazing-incidence microscopes with home-lab source
Authors: Li Yaran , Xie Qing , Chen Zhiqiang , Xin Qiuqi , Wang Xin , Mu Baozhong , Wang Zhanshan , Liu Shenye , Ding Yongkun
Published: January 2018

Direct intensity calibration of X-ray grazing-incidence microscopes is urgently needed in quantitative studies of X-ray emission from laser plasma sources in inertial confinement fusion. The existing calibration methods for single reflecting mirrors, crystals, gratings, filters, and X-ray detectors are not applicable for such X-ray microscopes due to the specific optical structure and the restrictions of object-image relation. This article presents a reliable and efficient method that can be performed using a divergent X-ray source and an energy dispersive Si-PIN (silicon positive-intrinsic-negative) detector in an ordinary X-ray laboratory. The transmission theory of X-ray flux in imaging diagnostics is introduced, and the quantities to be measured are defined. The calibration method is verified by a W/Si multilayer-coated Kirkpatrick-Baez microscope with a field of view of ∼95 μm at 17.48 keV. The mirror reflectance curve in the 1D coordinate is drawn with a peak value of 20.9% and an uncertainty of ∼6.0%.
Defect-induced instability mechanisms of sputtered amorphous indium tin zinc oxide thin-film transistors
Authors: Park Jinhee , Rim You Seung , Li Chao , Wu Jiechen , Goorsky Mark , Streit Dwight
Published: January 2018

We report the device performance and stability of sputtered amorphous indium-tin-zinc-oxide (ITZO) thin-film transistors as a function of oxygen ratio [O2/(Ar + O2)] during growth. Increasing the oxygen ratio enhanced the incorporation of oxygen during ITZO film growth and reduced the concentration of deep-level defects associated with oxygen vacancies. Under illumination with no bias stress, device stability and persistent photocurrent were improved with increased oxygen ratio. Bias stress tests of the devices were also performed with and without illumination. While high oxygen ratio growth conditions resulted in decreased deep-level oxygen vacancies in the ITZO material, the same conditions resulted in degradation of the interfacial layer between the ITZO channel and dielectric due to the migration of energetic oxygen ions to the interface. Therefore, when bias stress was applied, increased carrier trap density at the interface led to a decrease in device stability that offsets any improvement in the material itself. In order to take advantage of the improved ITZO material growth at a high oxygen ratio, the interface-related problems must be solved.
Cutoff probe measurement in a magnetized plasma
Authors: You K. H. , You S. J. , Na B. K. , Kim D. W. , Kim J. H. , Seong D. J. , Chang H. Y.
Published: January 2018

This paper proposes a model for a cutoff probe that can be applied even in magnetized plasma. By choosing an adequate permittivity element in the tensor of the gyrotropic Drude model and applying it to the previous cutoff probe model, a generalized expression for the cutoff frequency (fcut) of the magnetized cutoff probe is formulated as follows: fcut2≈fuh2=fpe2+fce2, where fuh, fpe, and fce are the upper hybrid frequency, plasma frequency, and gyro-frequency, respectively. The detailed theory and experiment to support this result are presented and discussed through this paper.
Propagation speed, linear stability, and ion acceleration in radially imploding Hall-driven electron-magnetohydrodynamic shocks
Authors: Richardson A. S. , Swanekamp S. B. , Jackson S. L. , Mosher D. , Ottinger P. F.
Published: January 2018

Plasma density gradients are known to drive magnetic shocks in electron-magnetohydrodynamics. Previous slab modeling has been extended to cylindrical modeling of radially imploding shocks. The main new effect of the cylindrical geometry is found to be a radial dependence in the speed of shock propagation. This is shown here analytically and in numerical simulations. Ion acceleration by the magnetic shock is shown to possibly become substantial, especially in the peaked structures that develop in the shock because of electron inertia.
Interactive social contagions and co-infections on complex networks
Authors: Liu Quan-Hui , Zhong Lin-Feng , Wang Wei , Zhou Tao , Eugene Stanley H.
Published: January 2018

What we are learning about the ubiquitous interactions among multiple social contagion processes on complex networks challenges existing theoretical methods. We propose an interactive social behavior spreading model, in which two behaviors sequentially spread on a complex network, one following the other. Adopting the first behavior has either a synergistic or an inhibiting effect on the spread of the second behavior. We find that the inhibiting effect of the first behavior can cause the continuous phase transition of the second behavior spreading to become discontinuous. This discontinuous phase transition of the second behavior can also become a continuous one when the effect of adopting the first behavior becomes synergistic. This synergy allows the second behavior to be more easily adopted and enlarges the co-existence region of both behaviors. We establish an edge-based compartmental method, and our theoretical predictions match well with the simulation results. Our findings provide helpful insights into better understanding the spread of interactive social behavior in human society.
Thermal dependence of the lateral shift of a light beam reflected from a liquid crystal cell deposited on a magnetic film
Authors: Dadoenkova Y. S. , Bentivegna F. F. L. , Petrov R. V. , Bichurin M. I.
Published: January 2018

We study the influence of the thermo-optic effect and of thermal expansion on the lateral shift experienced by a Gaussian near-infrared beam upon reflection from a voltage-controlled nematic liquid crystal cell deposited on a magnetic yttrium-iron garnet film. Variations of temperature are considered in the range between room temperature and the nematic-isotropic phase transition temperature of the liquid crystal and induce changes in both the layer thicknesses and the permittivity tensor components of the constituents. We show that for all polarization configurations of the incoming and reflected beams, these changes modify the amplitude of the extrema of the lateral beam shift and their position with respect to the incidence angle of the beam and, except in the s–s polarization configuration, to the voltage applied to the liquid crystal cell. In the p–p and p–s polarization configurations, this drift can thus be controlled at some incidence angles by tuning the applied voltage. Moreover, in the p–s configuration, the lateral shift can be also controlled by a magnetization reversal in the magnetic layer. Finally, we discuss the possibility of temperature monitoring using the temperature dependence of the lateral shift in this system.
431 kA/cm2 peak tunneling current density in GaN/AlN resonant tunneling diodes
Authors: Growden Tyler A. , Zhang Weidong , Brown Elliott R. , Storm David F. , Hansen Katurah , Fakhimi Parastou , Meyer David J. , Berger Paul R.
Published: January 2018

We report on the design and fabrication of high current density GaN/AlN double barrier resonant tunneling diodes grown via plasma assisted molecular-beam epitaxy on bulk GaN substrates. A quantum-transport solver was used to model and optimize designs with high levels of doping and ultra-thin AlN barriers. The devices displayed repeatable room temperature negative differential resistance with peak-to-valley current ratios ranging from 1.20 to 1.60. A maximum peak tunneling current density (Jp) of 431 kA/cm2 was observed. Cross-gap near-UV (370–385 nm) electroluminescence (EL) was observed above +6 V when holes, generated from a polarization induced Zener tunneling effect, recombine with electrons in the emitter region. Analysis of temperature dependent measurements, thermal resistance, and the measured EL spectra revealed the presence of severe self-heating effects.
Communication: Exact analytical derivatives for the domain-based local pair natural orbital MP2 method (DLPNO-MP2)
Authors: Pinski Peter , Neese Frank
Published: January 2018

Electron correlation methods based on pair natural orbitals (PNOs) have gained an increasing degree of interest in recent years, as they permit energy calculations to be performed on systems containing up to many hundred atoms, while maintaining chemical accuracy for reaction energies. We present an approach for taking exact analytical first derivatives of the energy contributions in the simplest method of the family of Domain-based Local Pair Natural Orbital (DLPNO) methods, closed-shell DLPNO-MP2. The Lagrangian function contains constraints to account for the relaxation of PNOs. RI-MP2 reference geometries are reproduced accurately, as exemplified for four systems with a substantial degree of nonbonding interactions. By the example of electric field gradients, we demonstrate that omitting PNO-specific constraints can lead to dramatic errors for orbital-relaxed properties.
Iterative random forests to discover predictive and stable high-order interactions
Authors: Basu Sumanta , Kumbier Karl , Brown James B. , Yu Bin
Published: January 2018

Significance

We developed a predictive, stable, and interpretable tool: the iterative random forest algorithm (iRF). iRF discovers high-order interactions among biomolecules with the same order of computational cost as random forests. We demonstrate the efficacy of iRF by finding known and promising interactions among biomolecules, of up to fifth and sixth order, in two data examples in transcriptional regulation and alternative splicing.
Communicating archaeological heritage
Authors: Noor Shuhaida Md , Jaafar Mastura , Balan Yugeetha
Published: January 2018

Existing archaeological heritage communication focuses on educating the public by emphasising scientific knowledge from the perspectives of experts (e.g. archaeologists), often sidelining the perspectives of the local community. Nevertheless, the local community’s perspective is equally important in providing humanistic insights and in connecting the past to the present context. This research explores how local communities make meaning of and relate heritage to their social identity. In-depth interviews were conducted with 20 purposely-sampled representatives from various local community groups in Lenggong Valley, Malaysia; including village heads, village elders and individuals from various social and cultural backgrounds. The findings provide interesting insights into how the local community defines and connects to heritage. Importantly, this study highlights multilayered dimensions of archaeological heritage that are intricately connected to contemporary society. Incorporating these wider dimensions into archaeological heritage communication will result in communication that is more socially, culturally and psychologically relevant, thus engendering greater interest and appreciation.
Understanding online consumption of public affairs news in
Malaysia
Authors: Omar Bahiyah , Ismail Nurzali , Kee Ng See
Published: January 2018

Evidence from past news research suggested that people are less interested to
read hard news including public affairs news. Focusing on Malaysia, this study
examines the role of demographic variables, mobile and social media use for
news, perceived news credibility and users’ motivations for news in explaining
online consumption of public affairs news in the setting which is known for its
tight media control. An online survey was employed to collect data from
Malaysian Internet users, aged between 18 and 64, who regularly read news
online. Data were analyzed using multiple regression. The findings of the study
suggest that digital immigrants, or older news users, are more likely to consume
public affairs news than young ones. Malaysians read public affairs news which
they perceive to be highly credible to fulfill their information and social
needs. News organizations in Malaysia can use these findings to design a
strategic approach for a more competitive news industry.
Lexical chains and topic continuity in the register of popular
scientific writing
Authors: Hützen Nicole , Serbina Tatiana
Published: January 2018

This article presents a corpus study of lexical chains in the register of popular
scientific writing, based on the English and German original texts included in
the CroCo Corpus. This register is characterized by patterns resulting from the
combination of accessible knowledge and scientific validity. The study aims at
investigating cross-linguistic differences in terms of frequency and length of
lexical chains. Chain elements are extracted by identifying the most frequent
noun per text (and any lexical items associated with it by synonymy, hyponymy,
or meronymy). The sentence IDs in the corpus markup are used to automatically
calculate distances between occurrences of the target items. The analysis of
immediacy chains and discontinuities in chains supports the investigation of
contrasts in terms of topic continuity patterns.
The question of power in language classes from a critical discourse analysis perspective
Authors: Babaii Esmat , Parsazadeh Abbas , Moradi Hassan
Published: January 2018

Informed by the major tenets of critical discourse analysis, the present study attempted to expose the chasm between veteran English teachers enjoying a nation-wide popularity and those linguistically talented novices achieving locally mediocre fame in the Iranian EFL context. In so doing, two highly competent English teachers, each as a prime example of the above-mentioned camps, were selected to serve as the main participants of the research. The analysis of their classroom talk indicated that linguistic excellence could not fulfill the role of educated experience as far as discourse competence was concerned. In all, the discursive strategies used by the experienced teacher seemed to manifest his recognition of students' voices and created a more heteroglossic atmosphere in the classroom.
Lexicography, discourse and power
Authors: Chen Wenge
Published: January 2018

This paper conceptualizes dictionary bilingualization as a recontextualizing practice and explores how ideology and power play out in the recontextualization of lexicographic discourse across languages and cultures to result in the transformation of meaning. It first proposes viewing the (bilingualized) dictionary as discourse and emphasizes bilingual lexicography as a site of an asymmetrical linguistic and cultural power dynamics. The paper then argues that a synergy of critical discourse analysis and postcolonial studies can reveal the inter-cultural ideological struggle implicit in the bilingualizing lexicographic practice. The body of the study is devoted to the analysis of those shifts taking place in the entries, definition, illustrative examples and pragmatic labels in a bilingualized English-Chinese dictionary, which, when viewed cumulatively, significantly reshape the ideological positioning of the dictionary. The paper discusses the implications for critical lexicographic studies and for research into the interplay between power and resistance between dominating and dominated cultures. It concludes that Periphery English dictionary compilers are able to negotiate the different subjectivities and ideologies inherent in dictionary making and to adopt a subject position favorable to their empowerment in the international English lexicography, although such resistance is far from capable of restructuring the order of lexicography.
Aptitude measures in SLA
Authors: Wagener Thomas
Published: January 2018

The present study examines a US Department of Defense (DOD) foreign language
program using linear and logistic regression to model foreign language
proficiency growth over three time intervals. The analysis demonstrates growth
from start to finish for a program involving domestic immersion and study abroad
and tests the ability of aptitude and achievement measures to predict that
growth for a group of 80 students. The findings suggest that a measure of
foreign language aptitude and a measure of quantitative aptitude differentiate
learning outcomes for the intensive domestic immersion portion of the program
while measures of quantitative aptitude and native language verbal aptitude
differentiate later-stage learners on the study abroad portion of the
program.
Construal of content
Authors: Healy Christina
Published: January 2018

Interpreting requires a nuanced understanding of language, andWilcox and Shaffer (2005)propose that interpreting is enhanced by adopting a cognitive model of communication rather than the conduit model implicit in many interpreting pedagogy models. The present study used a cognitive linguistic approach to investigate affective constructions in American Sign Language (ASL). Relative cognitive linguistic principles are reviewed in the context of English affective constructions and applied in reporting the ASL findings. Then the article explores how these theoretical concepts can support meaning-transfer work. Specifically, Langacker’s Stage Model (2008) is expanded as a framework for comparing source and target text construals of events and for presenting a message with equivalent impact through different language-specific strategies.
Strength of Mg–3%Al alloy in presence of graphene nano-platelets as reinforcement
Authors: Kumar Pravir , Mallick Ashis , Kujur Milli Suchita , Tun Khin Sandar , Shabadi Rajashekhara , Gupta Manoj
Published: January 2018

Bulk Mg–3%Al alloy-based nanocomposites containing graphene nano-platelets (GNPs) were synthesised using the powder metallurgy technique incorporating energy efficient hybrid microwave sintering and hot extrusion. GNPs in amounts of 0.1, 0.3 and 0.5 wt-% were investigated as reinforcements. Microstructural characterisation accomplished using optical, scanning and transmission electron microscopy revealed the presence of minimal porosity (<1%), a uniform distribution of GNPs in the matrix and a reduced grain size as a result of the presence of GNPs. The results of mechanical property characterisation revealed an overall improvement in micro-hardness and compressive response, due to the presence of GNPs, with best results exhibited by the Mg–3Al/0.3% GNPs composite. The ductility under compressive loading for composite samples remained higher than 20%.
Recycling for my neighbourhood? Using place identity and social norms to promote pro-environmental behaviour / ¿Reciclar para mi barrio? Empleando la identidad de lugar y las normas sociales para fomentar el comportamiento pro-ambiental
Authors: Lima Maria-Luísa , Branco Carla
Published: January 2018

Pro-environmental behaviour has often been studied as being the result of individual or rational decision making, despite the contributions from a more social approach to environmental psychology. This paper presents experimental research addressing the role of social identities and social norms in promoting pro-environmental behaviour. Following the frameworks of Social Identity Theory and Normative Focus Theory, we expect that descriptive social norms will have an impact on behaviour and that social identity will moderate this association.

Place identity and descriptive norms regarding pro-environmental behaviour were manipulated in three studies. Self-reported intentions to recycle were assessed, after controlling for past recycling behaviour and environmental identity. The first study (participants: N = 43) showed that the intention of recycling was stronger when descriptive norm was higher. The second ( N‍‍‍ = ‍37) and the third ( N = 65) studies showed an interesting interaction effect: the salience of social identity was effective when the descriptive social norm was low, and the salience of personal identity promoted recycling when the descriptive social norm was high. These results are expected to stimulate new areas of research in this domain.
Enucleated cells reveal differential roles of the nucleus in cell migration, polarity, and mechanotransduction
Authors: Graham David M. , Andersen Tomas , Sharek Lisa , Uzer Gunes , Rothenberg Katheryn , Hoffman Brenton D. , Rubin Janet , Balland Martial , Bear James E. , Burridge Keith
Published: January 2018

The nucleus has long been postulated to play a critical physical role during cell polarization and migration, but that role has not been defined or rigorously tested. Here, we enucleated cells to test the physical necessity of the nucleus during cell polarization and directed migration. Using enucleated mammalian cells (cytoplasts), we found that polarity establishment and cell migration in one dimension (1D) and two dimensions (2D) occur without the nucleus. Cytoplasts directionally migrate toward soluble (chemotaxis) and surface-bound (haptotaxis) extracellular cues and migrate collectively in scratch-wound assays. Consistent with previous studies, migration in 3D environments was dependent on the nucleus. In part, this likely reflects the decreased force exerted by cytoplasts on mechanically compliant substrates. This response is mimicked both in cells with nucleocytoskeletal defects and upon inhibition of actomyosin-based contractility. Together, our observations reveal that the nucleus is dispensable for polarization and migration in 1D and 2D but critical for proper cell mechanical responses.
Identifying the Invariants for Classical Knots and Links from the Yokonuma–Hecke Algebras
Authors: Chlouveraki Maria , Juyumaya Jesús , Karvounis Konstantinos , Lambropoulou Sofia
Published: January 2018

We announce the existence of a family of new 2-variable polynomial invariants for oriented classical links defined via a Markov trace on the Yokonuma–Hecke algebra of type A. Yokonuma–Hecke algebras are generalizations of Iwahori–Hecke algebras, and this family contains the HOMFLYPT polynomial, the famous 2-variable invariant for classical links arising from the Iwahori–Hecke algebra of type A. We show that these invariants are topologically equivalent to the HOMFLYPT polynomial on knots, but not on links, by providing pairs of HOMFLYPT-equivalent links that are distinguished by our invariants. In order to do this, we prove that our invariants can be defined diagrammatically via a special skein relation involving only crossings between different components. We further generalize this family of invariants to a new 3-variable skein link invariant that is stronger than the HOMFLYPT polynomial. Finally, we present a closed formula for this invariant, by W. B. R. Lickorish, that uses HOMFLYPT polynomials of sublinks and linking numbers of a given oriented link.
Can Computed Tomography Accurately Measure Acetabular Anterversion in Developmental Dysplasia of the Hip? Verification and Characterization Using 3D Printing Technology
Authors: Cai Zhencun , Zhao Qun , Li Lianyong , Zhang Lijun , Ji Shijun
Published: January 2018

Background:

One of the important pathologic changes in developmental dysplasia of the hip (DDH) is increased acetabular version angle (AA). Reasonable correction for excessive AA is an important step in the treatment of DDH, making accurate AA measurement very crucial. However, the results of different AA measurement methods vary. Thus, this study aimed to compare the difference in AA measurements between 2-dimensional computed tomography (2D-CT) and 3-dimensional computed tomography (3D-CT) in children with DDH and to identify the AA degree in children with DDH to guide treatment.

Methods:

AA was measured by 2D-CT and 3D-CT in 186 children with DDH, and the measurement results were compared with the physical measurement result in the 3D-printed pelvis (3D-PP) model. The 3D-PP was a 1:1 model identical to the human pelvis. All patients were unilaterally affected.

Results:

The results of AA measurement through 2D-CT, 3D-CT, and 3D-PP of normal hips were 14.0±6.6, 11.9±5.3, and 11.9±3.4 degrees, respectively, whereas those of the dislocated hips were 24.9±8.9, 19.8±5.2, and 19.5±4.3 degrees, respectively. In both the normal and dislocated hip groups, the results between 2D-CT and 3D-CT was significantly different (P<0.05), but there was no difference between the results of 3D-CT and 3D-PP (P>0.05). The AA of the normal and dislocated hips as measured by 3D-PP was 11.9±3.6 and 19.6±4.3 degrees, respectively, with statistically significant difference (P<0.05). In the dislocated hips, a significant positive correlation was found between age and AA (r=0.756, P<0.05) and between AA and degree of dislocation (r=0.837, P<0.05).

Conclusions:

3D-CT is more accurate than 2D-CT for AA measurement, and compared with normal hips, AA in dislocated hips increased by ∼7.7 degrees on average. AA increases as age and degree of dislocation increase.

Level of Evidence:

Level II.
Clinical Significance of Venous Anomalies in Syndromic Craniosynostosis
Authors: Copeland Andrea E. , Hoffman Caitlin E. , Tsitouras Vassilios , Jeevan Dhruve S. , Ho Emily S. , Drake James M. , Forrest Christopher R.
Published: January 2018

Background:

The pattern of cranial venous drainage in syndromic craniosynostosis is unpredictable and not adequately understood. Collateral channels substitute for stenotic venous sinuses and pose potential risk for surgical intervention. The purpose of this study was to analyze the patterns of venous drainage in patients with syndromic craniosynostosis and their influence on operative planning and morbidity.

Methods:

A retrospective study of patients with syndromic craniosynostosis from 2000 to 2013 was performed. Demographic data were collected including phenotype and associated pathologies. Pre- and/or postoperative venous imaging was reviewed for venous sinus stenosis, collateral emissaries, and persistent fetal sinuses. Categorization of anomalous venous drainage was performed, and the relationship with surgical morbidity was assessed.

Results:

Forty-one patients were identified. Anomalies were present in 31 patients (76%) consisting of dural sinus stenosis in 28 (68%), dilated emissaries in 26 (63%), and fetal sinuses in 7 (17%). Pfeiffer syndrome was most commonly associated with anomalous drainage (100%). Venous anomalies were associated with elevated intracranial pressure (ICP), shunted hydrocephalus, Chiari malformations, and sleep apnea. In 5 cases, the surgical plan was adjusted based on anomalous anatomy. No mortalities occurred. Intraoperative complication rate was 7.3%, all with anomalous drainage. Median estimated blood loss was 1,100 cc for patients with anomalies versus 400 cc without anomalies (P = 0.181).

Conclusion:

Cranial venous anomalies are commonly detected in patients with syndromic craniosynostosis and may affect surgical morbidity and outcome with a higher estimated blood loss, alteration of procedure, and postoperative morbidity. Detailed preoperative imaging of the venous drainage is therefore recommended in cases of syndromic synostosis.
Spinal protein kinase C/extracellular signal–regulated kinase signal pathway mediates hyperalgesia priming
Authors: Chen Wei-Hsin , Chang Ya-Ting , Chen Yong-Cyuan , Cheng Sin-Jhong , Chen Chien-Chang
Published: January 2018

Chronic pain can be initiated by one or more acute stimulations to sensitize neurons into the primed state. In the primed state, the basal nociceptive thresholds of the animal are normal, but, in response to another hyperalgesic stimulus, the animal develops enhanced and prolonged hyperalgesia. The exact mechanism of how primed state is formed is not completely understood. Here, we showed that spinal protein kinase C (PKC)/extracellular signal–regulated kinase (ERK) signal pathway is required for neuronal plasticity change, hyperalgesic priming formation, and the development of chronic hyperalgesia using acid-induced muscle pain model in mice. We discovered that phosphorylated extracellular signal–regulated kinase–positive neurons in the amygdala, spinal cord, and dorsal root ganglion were significantly increased after first acid injection. Inhibition of the phosphorylated extracellular signal–regulated kinase activity intrathecally, but not intracerebroventricularly or intramuscularly before first acid injection, prevented the development of chronic pain induced by second acid injection, which suggests that hyperalgesic priming signal is stored at spinal cord level. Furthermore, intrathecal injection of PKC but not protein kinase A blocker prevented the development of chronic pain, and PKC agonist was sufficient to induce prolonged hyperalgesia response after acid injection. We also found that mammalian target of rapamycin–dependent protein synthesis was required for the priming establishment. To test whether hyperalgesic priming leads to synaptic plasticity change, we recorded field excitatory postsynaptic potentials from spinal cord slices and found enhanced long-term potentiation in mice that received one acid injection. This long-term potentiation enhancement was prevented by inhibition of extracellular signal–regulated kinase. These findings show that the activation of PKC/ERK signal pathway and downstream protein synthesis is required for hyperalgesic priming and the consolidation of pain singling.
Risk of preterm birth following late pregnancy exposure to NSAIDs or COX-2 inhibitors
Authors: Bérard Anick , Sheehy Odile , Girard Sylvie , Zhao Jin-Ping , Bernatsky Sasha
Published: January 2018

Pregnant women may take nonsteroidal antiinflammatory drugs (NSAIDs), selective cyclooxygenase (COX)-2 inhibitors, or biological agents to relieve symptoms or manage disease flares in late pregnancy. We aimed to quantify the risk of prematurity associated with late pregnancy exposure to nonselective NSAIDs, selective COX-2 inhibitors, and biological agents. Using data from Quebec Pregnancy Cohort, we performed a population-based cohort study. We included all women who were covered by the Quebec Drug Plan and had a singleton live birth between January 1, 1998 and December 31, 2009. Late pregnancy exposure was defined as having filled at least 1 prescription for nonselective NSAIDs, selective COX-2 inhibitors, or biological agents in the 3 months before delivery. Prematurity was defined as <37 weeks of gestation. Crude and adjusted odds ratios (OR) were obtained using generalized estimation equation models. Covariates included maternal autoimmune diseases, demographics, concomitant drug use, history of pregnancy complications, and other comorbidities. A total of 156,531 pregnancies met inclusion criteria and were considered for analyses. In the 3 months before delivery, 391 pregnancies were exposed to nonselective NSAIDs, 55 to COX-2 inhibitors, and 12 to biological agents. After adjustment for maternal autoimmune diseases, concomitant medication use, and other risk factors, COX-2 inhibitor use in late pregnancy was associated with a 2.46-fold increased risk of prematurity (adjusted OR, 2.46; 95% confidence interval, 1.28-4.72) compared to nonuse; only late pregnancy exposure to celecoxib was found to increase the risk (adjusted OR, 3.41; 95% confidence interval, 1.29-9.02). In conclusion, celecoxib use during late pregnancy may increase the risk of prematurity.
The role of patient registries for rare genetic lipid disorders
Authors: Ng David M. , Hooper Amanda J. , Bellgard Matthew I. , Burnett John R.
Published: January 2018

Purpose of review

We review the role, utility and current status of patient registries for rare genetic lipid disorders.

Recent findings

The creation and maintenance of rare genetic lipid disorder patient registries is critical for disease monitoring, improving clinical best practice, facilitating research and enabling the development of novel therapeutics. An open-source disease registry platform, termed the Rare Disease Registry Framework, has been developed, optimized and deployed for homozygous familial hypercholesterolemia. A global disease-specific registry for lipoprotein lipase deficiency (LPLD), GENetherapy In the mAnagement of Lipoprotein Lipase deficiency, has been established with the aim of enrolling 20–40% of LPLD patients worldwide and will study the natural history of LPLD as well as therapeutic response to the gene therapy alipogene tiparvovec. Similarly, a registry for lysosomal acid lipase deficiency patients in Europe and the United States is studying the clinical outcomes of the enzyme-replacement therapy sebelipase alfa.

There are currently few disease-specific rare lipid disorder patient registries. The very nature of rare genetic lipid disorders would suggest that larger national or international registries are necessary to capture clinical data on a sufficient number of patients to provide insight into the prevalence and natural history of these conditions. Furthermore, these registries can help to identify and address deficiencies in current diagnostic and management practices, and facilitate clinical trials of new therapies.
Forty Years of Lower Extremity Take-Backs: Flap Type Influences Salvage Outcomes
Authors: Stranix John T. , Lee Z-Hye , Jacoby Adam , Anzai Lavinia , Mirrer Josh , Avraham Tomer , Thanik Vishal , Levine Jamie P. , Saadeh Pierre B.
Published: January 2018

Background:

Considering that muscle has higher metabolic demand than fasciocutaneous tissue and can be more difficult to monitor clinically, the authors compared take-back salvage rates between fasciocutaneous and muscle free flaps for lower extremity trauma reconstruction.

Methods:

The authors conducted a retrospective review of 806 free flaps (1979 to 2016); 481 soft-tissue flaps performed for below-knee trauma met inclusion criteria. Primary outcome measures were perioperative complications, specifically, take-backs and flap salvage rates. Univariate and multivariate regression analysis was performed where appropriate.

Results:

Take-backs occurred in 71 flaps (muscle,n= 44; fasciocutaneous,n= 27) at an average of 3.7 ± 5.4 days postoperatively. Indications were venous (48 percent), arterial (31 percent), unknown (10 percent), and hematoma (10 percent). Overall outcomes were complete salvage (37 percent), partial failure (25 percent), and total failure (38 percent). Take-backs occurring within 48 hours postoperatively correlated with higher salvage rates (p= 0.022). Fasciocutaneous flaps demonstrated increased take-back rates compared with muscle flaps (p= 0.005) that more frequently occurred within 48 hours postoperatively (relative risk, 13.2;p= 0.012). Fasciocutaneous flaps were successfully salvaged more often than muscle-based flaps (p< 0.001). Multivariable regression strongly demonstrated higher risk of take-back failure for muscle flaps (relative risk, 9.42;p= 0.001), despite higher take-back rates among fasciocutaneous flaps (relative risk, 2.28;p= 0.004).

Conclusions:

Compared with muscle-based flaps, fasciocutaneous flaps demonstrated earlier and more frequent take-backs for suspected vascular compromise, with higher successful take-back salvage rates. Furthermore, muscle flaps with skin paddles also demonstrated better salvage outcomes than those without. These findings may reflect a combination of lower metabolic demand and easier visual recognition of vascular compromise in fasciocutaneous tissue.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, III.
Neuroimaging in neurodevelopmental disorders: focus on resting-state fMRI analysis of intrinsic functional brain connectivity
Authors: Jack Allison
Published: January 2018

Purpose of review

Resting-state fMRI assessment of instrinsic functional brain connectivity (rs-fcMRI) in autism spectrum disorders (ASD) allows assessment of participants with a wide range of functioning levels, and collection of multisite databases that facilitate large-scale analysis. These heterogeneous multisite data present both promise and methodological challenge. Herein, we provide an overview of recent (1 October 2016–1 November 2017) empirical research on ASD rs-fcMRI, focusing on work that helps clarify how best to leverage the power of these data.

Recent findings

Recent research indicates that larger samples, careful atlas selection, and attention to eye status of participants will improve the sensitivity and power of resting-state fMRI analyses conducted using multisite data. Use of bandpass filters that extend into a slightly higher frequency range than typical defaults may prevent loss of disease-relevant information. Connectivity-based parcellation as an approach to region of interest analyses may allow for improved understanding of functional connectivity disruptions in ASD. Treatment approaches using rs-fcMRI to determine target engagement, predict treatment, or facilitate neurofeedback demonstrate promise.

Rs-fcMRI data have great promise for biomarker identification and treatment development in ASD; however, ongoing methodological development and evaluation is crucial for progress.