bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphogenetic movements in the neural plate and neural tube: mouse
Authors: Massarwa R'ada , Ray Heather J. , Niswander Lee
Published: May 2013

The neural tube (NT), the embryonic precursor of the vertebrate brain and spinal cord, is generated by a complex and highly dynamic morphological process. In mammals, the initially flat neural plate bends and lifts bilaterally to generate the neural folds followed by fusion of the folds at the midline during the process of neural tube closure (NTC). Failures in any step of this process can lead to neural tube defects (NTDs), a common class of birth defects that occur in approximately 1 in 1000 live births. These severe birth abnormalities include spina bifida, a failure of closure at the spinal level; craniorachischisis, a failure of NTC along the entire body axis; and exencephaly, a failure of the cranial neural folds to close which leads to degeneration of the exposed brain tissue termed anencephaly. The mouse embryo presents excellent opportunities to explore the genetic basis of NTC in mammals; however, its in utero development has also presented great challenges in generating a deeper understanding of how gene function regulates the cell and tissue behaviors that drive this highly dynamic process. Recent technological advances are now allowing researchers to address these questions through visualization of NTC dynamics in the mouse embryo in real time, thus offering new insights into the morphogenesis of mammalian NTC. WIREs Dev Biol 2014, 3:59–68. doi: 10.1002/wdev.120

This article is categorized under:

Early Embryonic Development > Gastrulation and Neurulation

Nervous System Development > Vertebrates: Regional Development

Birth Defects > Craniofacial and Nervous System Anomalies
Estimation of black‐tailed prairie dog colonies in Montana
Authors: Rauscher Ryan L. , Story Scott J. , Gude Justin A. , Russell Robin E.
Published: May 2013

Black‐tailed prairie dog (Cynomys ludovicianus) is an influential species in prairie ecosystems. Accurate estimates of active prairie dog colony area are needed to assess the status of the species and evaluate the effects of management actions. In 2008, Montana Fish, Wildlife and Parks conducted a survey of potential black‐tailed prairie dog habitat. Using fixed‐wing aircraft and an aerial line‐intercept method, we surveyed 771 transects totaling 56,530 km in 32 counties in central and eastern Montana, USA, excluding tribal lands. We recorded 667 black‐tailed prairie dog colony intercepts totaling 336,636 m in 21 counties. Ground intercepts were 1.091 (95% credible intervals = 1.087–1.094) times longer than air intercepts. The estimated percent of colonies classified as active from the air that were active on the ground was 86.8% (95% credible intervals = 77.9–93.5%). Corrected estimates resulted in 77,430 ha (95% credible intervals = 69,480–83,380) of active and 12,990 ha (95% credible intervals = 7,039–20,970) of inactive black‐tailed prairie dog colonies. We conducted a sensitivity analysis of the estimated area of active prairie dog colonies by reducing a percentage of long intercepts assumed to be entirely active. More than 30% of active intercepts >750 m in length would need to, in fact, be inactive in order for our active colony area estimates to differ >10,000 ha (13%; i.e., outside of our margin of error) from our estimates. Aerial line‐intercept methods provide a reliable and repeatable method for obtaining estimates of active and inactive prairie dog colony area over large areas. Our estimates provide the basis for long‐term monitoring of prairie dogs on a landscape scale. © 2013 The Wildlife Society.
National Survey of Fluid Therapy in Acute Pancreatitis: Current Practice Lacks a Sound Evidence Base
Authors: Haydock Matthew D. , Mittal Anubhav , van den Heever Marc , Rossaak Jeremy I. , Connor Saxon , Rodgers Michael , Petrov Maxim S. , Windsor John A. ,   Pancreas Network of New Zealand
Published: May 2013

Background

Fluid therapy (FT) is a critical intervention in managing acute pancreatitis (AP). There is a paucity of evidence to guide FT and virtually no data on current prescribing practice. This survey aims to characterize current practice and opinion with regard to FT in AP throughout New Zealand.

Methods

Information was collected on fluid selection, administration, and goal‐directed FT. The survey was distributed online and in print to all doctors employed in General Surgery Departments in New Zealand on 1 May 2012. Monthly email reminders were sent for 6 months.

Results

The overall response rate was 47 % (n= 190/408). Crystalloids were the preferred initial fluid for all categories of severity; however, colloid use increased with severity (p< 0.001). Fluid volume also increased with severity (p= 0.001), with 74 % of respondents prescribing >4 L for AP with organ failure (OF). Clinicians treating 26–50 patients per year with AP were less likely to prescribe colloid for AP with OF (8 vs 43 %) (p= 0.001). Rate of fluid administration in AP with OF varied according to physicians’ seniority (p= 0.004); consultants prescribed >4 L more than other groups (83 vs 68 %). Only 17 % of respondents reported the use of guidelines.

Conclusions

This survey reveals significant variation in prescription of FT for AP, and aggressive FT is commonly prescribed for AP with OF. There is little adherence to published guidelines or best available evidence.
Duration and Timing of Exposure to Neighborhood Poverty and the Risk of Adolescent Parenthood
Authors: Wodtke Geoffrey T.
Published: May 2013

Theory suggests that the impact of neighborhood poverty depends on both the duration and timing of exposure. Previous research, however, has not properly analyzed the sequence of neighborhoods to which children are exposed throughout the early life course. This study investigates the effects of different longitudinal patterns of exposure to disadvantaged neighborhoods on the risk of adolescent parenthood. It follows a cohort of children in the PSID from age 4 to 19 and uses novel methods for time-varying exposures that overcome critical limitations of conventional regression when selection processes are dynamic. Results indicate that sustained exposure to poor neighborhoods substantially increases the risk of becoming a teen parent and that exposure to neighborhood poverty during adolescence may be more consequential than exposure earlier during childhood.
Catalytic preference of Salmonella typhimurium LT2 sialidase for N‐acetylneuraminic acid residues over N‐glycolylneuraminic acid residues
Authors: Minami Akira , Ishibashi Sayaka , Ikeda Kiyoshi , Ishitsubo Erika , Hori Takanori , Tokiwa Hiroaki , Taguchi Risa , Ieno Daisuke , Otsubo Tadamune , Matsuda Yukino , Sai Saki , Inada Mari , Suzuki Takashi
Published: May 2013

In a comparison of sialidase activities toward N‐acetylneuraminic acid (Neu5Ac) and N‐glycolylneuraminic acid (Neu5Gc), we found that Salmonella typhimurium LT2 sialidase (STSA) hardly cleaved 4‐methylumbelliferyl Neu5Gc (4MU‐Neu5Gc). The k
cat/K
m value of STSA for 4MU‐Neu5Gc was found to be 110 times lower than that for 4‐methylumbelliferyl Neu5Ac (4MU‐Neu5Ac). Additionally, STSA had remarkably weak ability to cleave α2‐3‐linked‐Neu5Gc contained in gangliosides and equine erythrocytes. In silico analysis based on first‐principle calculations with transition‐state analogues suggested that the binding affinity of Neu5Gc2en is 14.3 kcal/mol more unstable than that of Neu5Ac2en. The results indicated that STSA preferentially cleaves Neu5Ac residues rather than Neu5Gc residues, which is important for anyone using this enzyme to cleave α2‐3‐linked sialic acids.
“Pay attention and take some notes”: Middle school youth, multimodal instruction, and notions of citizenship
Authors: Pellegrino Anthony M. , Zenkov Kristien , Calamito Nicholas
Published: May 2013

The study of a middle school social studies and literacy project this paper addresses occurred in the national capital region of the United States, where perceptions of “patriotism” and immigration policies were the subjects of frequent media reports. With this examination the authors considered one overarching research question: how do middle school students describe and illustrate citizenship when given access to multimodal texts and media (e.g., digital photography and slam poetry)? The authors called on young adolescents to create slam poems with incorporated images to address the question “What does it mean to be a ‘citizen’?”. The authors examined products of this project, which included surveys and slam poems, to address this research question, identifying findings that might inform social studies educators’ practices and curricula. Employing alternative and multimodal texts motivated students to engage with this project and to more candidly share expansive perspectives about what they believe makes a “citizen”.
Editorial
Authors: Lehmann Jennifer
Published: May 2013

No doubt the mid-year will see academic staff scurrying to complete Semester 1 teaching and marking, and those of you working in the field will be well into the swing of the year and facing a variety of funding issues as the new financial year emerges. The last few years have been difficult in terms of funding for health and community service programmes and, while the focus has been on enquiries into child abuse, mental health assessment of young children, the acute lack of affordable housing and pressures on single parents raising children, the Australian atmosphere, in general, is one of restraint and pulling back from funding of welfare services. This comes at a time when Australia has enjoyed much better financial well-being than many other countries in the world and, ironically, there appears to have been a drop in what the Government refers to as welfare dependency. However, as the population is continuing to increase and we are continuing to experience the economic losses associated with severe weather events and climate change, it seems we are also, as a nation, less inclined to be generous to those who experience ongoing disadvantage. The gap, according to Nicholas Biddle and Maxine Montaigne (2012) of the Australian National University, is not as great as that in the USA ‒ hardly something we would want to emulate‒ but is still increasing. While on average Australians have experienced an increase in income since the 2006 Census, this is not evenly distributed between states, regions and suburbs. We know that loss of a stable and sufficient income, as in the event of loss of employment, has major impacts on the well-being of family members and this was the message reiterated at the ‘Securing the Future’ Conference held last November. Clearly, we have a long way to go before our services will be able to truly address structural disadvantage.
Reading with Angels: Improving Literacy among Children in Foster Care
Authors: Knight Ruth
Published: May 2013

The Pyjama Foundation is an Australian charity working to improve the literacy and numeracy outcomes for children in foster care. The foundation delivers the Pyjama Foundation Love of Learning programme, a learning-based mentoring programme in which volunteer ‘Pyjama Angels’ visit children in care each week to read books, play games and engage in other learning-based activities.

This study surveyed 121 Love of Learning mentors (‘Pyjama Angels’) to assess their perceptions of the relationships they had developed with the children they mentored and of the children's improvement in their literacy skills, a key aim of the programme.

The statistical data analysis based on the structural equation modelling and multiple regression approach showed that several factors had a statistically significant impact on the mentors’ perceptions of the children's improvement in literacy skills: relationship with the child, child's engagement and tenure in the programme, and frequency of meetings. Age and gender of the mentors were not found to have a statistically significant impact on mentors’ perceptions of this improvement, while mentors’ perceptions of their relationship with the children was the most important factor influencing their perceptions of improvement in literacy skills. The study did not include objective measures of the children's literacy outcomes, so its results are limited to the mentors’ perceptions. However, this study offers valuable insights for mentoring programmes working with children living in foster care.
Regulating for Australia's Youngest Workers
Authors: van der Waarden Natalie
Published: May 2013

Child labour is a phrase associated with exploitation, poverty, insufficient education and various forms of physical abuse. These connotations do not match Australian perceptions about the employment of children and are not correlated with mainstream dialogue on teenagers in part time and casual employment. Child employment is an accepted part of Australian society, with older children making up a significant portion of the workforce. Minimum standards are increasingly regarded a critical safeguard for young Australians at work, evidenced by recent state level statutory amendment and enactment of dedicated legislation. This article makes two submissions; first, it suggests the regulation of young people's working conditions is inappropriately neglected at national level in Australia, and secondly, it proposes national standards should be set and equated with those in other developed economies, meeting international standards. The 1994 European Community Directive on the Protection of Young Workers is referred to as a suitable benchmark.
A structured process for reviewing the operation of the Mental Health Act 2001 in an Irish mental health service
Authors: Mulligan M. , Maher T. , Lucey J. V.
Published: May 2013

This paper provides a description of a structured template which allows review of the operation of the Mental Health Act 2001 at St Patrick's Mental Health Services (incorporating St Patrick's University Hospital, St Edmundsbury Hospital and Willow Grove Adolescent Unit). These structured processes were implemented to ensure rigorous monitoring of all clinical governance activities associated with adherence to the Mental Health Act (MHA) 2001. The paper describes in detail the information contained in the St Patrick's Mental Health Services dashboard for 2012. The dashboard displays the key performance indicators that are monitored and the paper describes how these were reviewed by the Hospital's Clinical Governance Committee on a weekly basis for the three approved centres. The dashboard has also been used by the Clinical Governance Committee to provide ongoing education and engagement with staff in order to improve the operation of the MHA 2001. The use of this structured monitoring process has allowed the hospital to measure adherence to the MHA 2001 and also to measure activities that impact directly on the care and treatment of patients detained under the Act. The use of structured monitoring tools (i.e. the dashboard) to review the operation of the MHA 2001 allows for coherent observation of key events and issues which can cause concern in terms of the operation of the Act.
Chronic oral carbamazepine treatment elicits mood-stabilising effects in mice
Authors: Kara Nirit Z. , Karpel Orit , Toker Lilach , Agam Galila , Belmaker Robert H. , Einat Haim
Published: May 2013

Objective

The underlying biology of bipolar disorder and the mechanisms by which effective medications induce their therapeutic effects are not clear. Appropriate use of animal models are essential to further understand biological mechanisms of disease and treatment, and further understanding the therapeutic mechanism of mood stabilisers requires that clinically relevant administration will be effective in animal models. The clinical regimens for mood-stabilising drugs include chronic oral administration; however, much of the work with animal models includes acute administration via injection. An effective chronic and oral administration of the prototypic mood stabiliser lithium was already established and the present study was designed to do the same for the mood stabiliser carbamazepine.

Methods

Mice were treated for 3 weeks with carbamazepine in food. ICR mice were treated with 0.25%, 0.5% and 0.75%, and C57bl/6 mice with 0.5% and 0.75%, carbamazepine in food (w/w, namely, 2.5, 5.0 or 7.5 g/kg food). Mice were then tested for spontaneous activity, forced swim test (FST), tail suspension test (TST) and amphetamine-induced hyperactivity.

Results

Oral carbamazepine administration resulted in dose-dependent blood levels reaching 3.65 μg/ml at the highest dose. In ICR mice, carbamazepine at the 0.5% dose had no effect on spontaneous activity, but significantly reduced immobility in the TST by 27% and amphetamine-induced hyperactivity by 28%. In C57bl/6 mice, carbamazepine at the 0.75% dose reduced immobility time in the FST by 26%.

Conclusions

These results demonstrate a behaviourally effective oral and chronic regimen for carbamazepine with mood stabilising-like activity in a standard model for mania-like behaviour and two standard models for depression-like behaviour.
Occurrence of the Ordovician-type aglaspididTremaglaspisin the Cambrian Weeks Formation (Utah, USA)
Authors: LEROSEY-AUBRIL RUDY , ORTEGA-HERNÁNDEZ JAVIER , KIER CARLO , BONINO ENRICO
Published: May 2013

The Guzhangian Weeks Formation preserves a diverse, yet virtually unstudied, non-trilobite arthropod fauna. Here we describeTremaglaspis vanroyisp. nov., the oldest representative of an enigmatic group of extinct arthropods, the Aglaspidida.Tremaglaspiswas previously known from the Lower Ordovician and its morphology was regarded as particularly derived within the clade. Its occurrence in the Cambrian of Utah suggests that much of the early evolutionary history of the Aglaspidida remains unknown. A review of the environmental settings of previous aglaspidid findings suggests that these arthropods preferentially inhabited shallow-water environments, which may partially explain their limited fossil record.
Effect of unidirectional water currents on displacement behaviour of the green sea urchin Strongylocentrous droebachiensis
Authors: Morse Bryan L. , Hunt Heather L.
Published: May 2013

Sea urchins can have important ecological effects on benthic communities through their aggregation and feeding behaviour. Urchin movement has been demonstrated to be negatively affected by wave action, but the impact of unidirectional tidal currents on urchin movement has not been investigated. This study examines the effect of unidirectional water velocity on the direction of displacement and movement rate of the green sea urchin, Strongylocentrotus droebachiensis. In laboratory flume experiments there was a clear effect of water currents on the displacement of sea urchins. At speeds ≤30 cm s−1 urchins moved across the current in a downstream direction, but at speeds of ≥36 cm s−1 the urchins switched directions by more than 90° and moved across the current in an upstream direction. There was a significant effect of flow speed on urchin movement speed, with urchin movement speed decreasing as water current speed increased.
Planters and Naturalists: Transnational Knowledge on Colonial Indigo Plantations in South Asia
Authors: KUMAR PRAKASH
Published: May 2013

The knowledge of indigo culture that developed on indigo plantations in colonial Bengal was remarkably cosmopolitan in its borrowings. The protean knowledge that was assembled in the first plantations in the Caribbean in the mid-seventeenth century had roots in various peasant traditions on the Indian subcontinent and elsewhere in the world. French naturalists committed this knowledge to texts, making them legible and portable whilst the needs of European empires ensured the perfection of this knowledge on separate continents even as it picked up heterogeneous forms at numerous sites. The heterogeneity of the knowledge attached to the practice of indigo manufacture was reproduced on the Indian subcontinent when indigo was reinvented as a colonial commodity. European planters generously drew on the texts describing indigo-making that were easily available, as the practice of dye making continued to evolve in the colonial locality. Some surviving peasant traditions of indigo culture on the subcontinent also impinged on the evolving knowledge. Thus multiple logics rather than the single colonial logic lay beneath the development of colonial indigo plantations in Bengal. An understanding of the process requires attention to the global genealogies of this knowledge system.
Comparative characterization of microRNA profiles of different genotypes ofToxoplasma gondii
Authors: XU M. J. , ZHOU D. H. , HUANG S. Y. , ZHAO F. R. , NISBET A. J. , LIN R. Q. , SONG H. Q. , ZHU X. Q.
Published: May 2013

The present study compared the miRNA expression profiles of fiveToxoplasma gondiistrains, namely RH (Type I, ToxoDB10), TgXD (Type I, ToxoDB10), PRU (Type II, ToxoDB1), QHO (Type II, ToxoDB1) and TgC7 (ToxoDB9), by Solexa deep sequencing, bioinformatics analysis and real-time quantitative PCR. A total of 7, 15, 10, 12 and 10 miRNAs were found from RH, TgXD, PRU, QHO and TgC7 strains, respectively. Thirteen miRNAs were shared by three genotypes, with only one miRNA shared by all of the 5 strains and others shared by 2 or more strains. A large number of targets ranging from 1 to 185 were identified for commonly shared miRNAs and strain-specific miRNAs with complete or nearly complete complementarity. Functional prediction showed that these targets were mostly focused on catalytic activity (191 targets) and binding activity (183 targets). Nonetheless, the majority of targets and most of the miRNAs are related to the virulence or invasion proteins of different strains ofT. gondii, including ROP and MIC, as well as some other proteins, such as AMA1, GRA and RHO. The present study characterized comparatively the miRNA profiles of 3 different genotypes ofT. gondii, identified genotype-shared miRNAs and strain-specific miRNAs.
Can parasites use predators to spread between primary hosts?
Authors: CABLE JOANNE , ARCHARD GABRIELLE A. , MOHAMMED RYAN S. , MCMULLAN MARK , STEPHENSON JESSICA F. , HANSEN HAAKON , van OOSTERHOUT COCK
Published: May 2013

Parasites typically have low reproductive fitness on paratenic hosts. Such hosts offer other significant inclusive fitness benefits to parasites, however, such as increased mobility and migration potential. The parasite fauna of the guppy (Poecilia reticulata) is dominated by the directly transmitted ectoparasites Gyrodactylus bullatarudis and Gyrodactylus turnbulli. In the wild, close predatory and competitive interactions occur between the guppy and the killifish Rivulus hartii. Previous observations suggest that these fish can share gyrodactylids, so we tested experimentally whether these parasites can use R. hartii as an alternative host. In aquaria, G. bullatarudis was the only species able to transmit from prey to predator. Both parasite species transferred equally well to prey when the predator was experimentally infected. However, in semi-natural conditions, G. bullatarudis transmitted more successfully to the prey fish. Importantly, G. bullatarudis also survived significantly longer on R. hartii out of water. As R. hartii can migrate overland between isolated guppy populations, G. bullatarudis may have an enhanced ability to disperse and colonize new host populations, consistent with its wider distribution in the wild. To our knowledge, this is the first empirical study demonstrating a predator acting as a paratenic host for the parasites of its prey.
Effect of cathode materials on the generation of runaway electron beams and X-rays in atmospheric pressure air
Authors: Zhang Cheng , Tarasenko Victor F. , Shao Tao , Baksht Evgeni Kh. , Burachenko Alexander G. , Yan Ping , Kostyray Igor' D.
Published: May 2013

In this work, experiments were performed to study the effect of cathode materials on the amplitude of the super-short avalanche electron beam (SAEB) current and X-ray density during discharges in atmospheric-pressure air. In the experiments, discharges were generated by three nanosecond-pulse generators in air gaps between a plane anode and a tubular cathode made of different metals. The output pulse of the three generators had a rise time of 0.3, 1, 15 ns, and a full width at half maximum of 1, 2, 30–40 ns, respectively. For the generators with pulse rise-time of 0.3 and 1 ns, the cathodes used in these experiments were made of stainless steel, permalloy, titanium, niobium, copper, brass, and aluminum. For the generator with pulse rise-time of 15 ns, the cathodes were made of stainless steel, titanium, copper, and aluminum. When the rise time of the applied pulse is 0.3 ns, our experimental results show that the amplitude of the voltage across the gap depends on the cathode material and reaches its maximum value when a stainless steel cathode is used. It is also observed that, under such situation, the maximum amplitudes of the SAEB current occur at maximum voltages across the gap when all other factors are equal. Furthermore, the amplitude of the SAEB current hereof is found to depend not only on the material of the sharp edge of the tubular cathode, but also on the material of the side surface of the tubular cathode. When the rise time of the applied pulse is 1 ns, the experimental results show that the average number of electrons in SAEB is also affected by the cathode materials. In addition, in the case that the rise time of the voltage pulse is 15 ns and the gap spacing is 8 cm, the experimental results show that the cathode material has no effect on the voltage amplitude across the gap and the X-ray density. The increase of the pulse repetition frequency from 250 to 500 Hz under such condition can lead to a three-fold increase in X-ray density in a repetitive pulsed mode.
Growth rate of modulation instability of a laser pulse propagating in clustered gas
Authors: Mishra Rohit K. , Jha Pallavi
Published: May 2013

This paper deals with the analysis of growth rate of modulation instability of a laser pulse propagating in a clustered gas. Finite pulse effects are considered to be a perturbation. Growth rates of modulation instability for 100 fs and 80 fs at the centroid as well as at the front and back of the pulses are evaluated and graphically analyzed. It has been shown that with decrease in pulse duration the growth rate of modulation instability increases at the front, back as well as at the centroid of the pulse. It is also shown that the change in growth rate of modulation instability at the front as well as at the back of the pulse in comparison to the centroid of the pulse for 80 fs pulse is less in comparison to that of 100 fs pulse.
A finger skill transfer system using a multi-fingered haptic interface robot and a hand motion image
Authors: Endo Takahiro , Kobayashi Mana , Kawasaki Haruhisa
Published: May 2013

The teaching of how to exert fingertip forces and how to move the fingers is essential for transferring skill using the fingers to perform fine motor tasks. In this paper we accomplish the transfer of fingertip forces and positions in three-dimensional space by combining a multi-fingered haptic interface robot, which can measure and present the three-dimensional forces and positions at five fingertips, and an image display system that records a trainer's hand image and displays it to a trainee. Several experimental results show a high fingertip force and position transferability and the great potential of our proposed transfer system.
Leaf physiological response to light environment of three tree fern species in a Mexican cloud forest
Authors: Riaño K. , Briones O.
Published: May 2013

Abundance and physiology of three understorey tree fern species were compared in a Mexican cloud forest. We hypothesized that the distribution of species would be associated with canopy openness and leaf physiological characteristics. In gullies (1–2% full sun), Alsophila firma was abundant, Cyathea divergens was distributed in moderately open places (4–9%), and Lophosoria quadripinnata preferred more open canopy (9–30%). Although 11 leaf traits of five plants of each species growing under closed and open canopies over 1 y did not differ within species, there were significant interspecific differences. Alsophila firma had comparatively low maximum electron transport rate ETRmax (26.8 ± 1.81 μmol m−2 s−1) and ETR light saturation point (ETRLSP: 261 ± 36.1 μmol m−2 s−1), high specific leaf area (SLA), thin leaves and decreased quantum yield during a leaf desiccation experiment. Cyathea divergens had relatively high maximum quantum yield (0.84 ± 0.004), ETRmax (37.3 ± 1.8 μmol m−2 s−1) and ETRLSP (409 ± 40.0 μmol m−2 s−1). Lophosoria quadripinnata had comparatively thick leaves, low SLA, high predawn water potential, high density (606 ± 25.5 mm−2) and small length (0.026 ± 0.002 mm) stomata. The results support the hypothesis that light sensitivity shapes tree fern distribution in the cloud forest.
X-ray powder diffraction data for compound Er3Co4Al12
Authors: Wen Zhenwei , Liu Chen , Zeng Lingmin , Yan Jialin
Published: May 2013

A new compound Er3Co4Al12 was prepared by arc melting under argon atmosphere. The powder X-ray diffraction data of Er3Co4Al12 were successfully indexed, giving a hexagonal structure with a = 8.6185(2) Å, c = 9.2347(3) Å, and unit-cell volume V = 594.04 Å3. Compound Er3Co4Al12 has the Gd3Ru4Al12 type-structure, Z = 2 and space group P63/mmc.
Synthesis and characterization of powder four borate Sr3Sm2(BO3)4
Authors: Si Jia-Yong , Cai Ge-Mei
Published: May 2013

Polycrystalline Sr3Sm2(BO3)4 borate has been synthesized through a solid-state reaction, and the title compound is stable in air and water. Its crystal structure was investigated from powder X-ray diffraction data using the Rietveld method. The fundamental building units of the crystal Sr3Sm2(BO3)4 are isolated BO3 anionic groups, distorted Sm–O polyhedra, and irregular Sr–O polyhedra, with the crystal structure isostructural to Sr3Nd2(BO3)4. The infrared spectrum of Sr3Sm2(BO3)4 has been measured, which is consistent with the crystallographic study. According to diffuse reflection measurement of Sr3Sm2(BO3)4 powders, the absorption edge is in the deep UV range and UV-vis transmittance is very high. Phosphor Sr3Sm2(BO3)4 exhibits an orange-red emission.
X-ray powder diffraction data for norandrostenedione
Authors: Tang Pei Xiao , Wu Xiao Qing , Pan Qing Qing , Zhang Li Li , Cheng Qiang , Li Hui
Published: May 2013

X-ray powder diffraction data, unit-cell parameters, and space group for norandrostenedione, C18H24O2, are reported [a = 26.3955(15) Å,b = 8.0476(4) Å,c = 7.3002(3) Å,α = β = γ = 90°, unit-cell volumeV = 1550.71 Å3,Z = 4, and space groupP212121]. All measured lines were indexed and are consistent with theP212121space group. No detectable impurity was observed.
The Politics of International Law and the Perils and Promises of Interdisciplinarity
Authors: AALBERTS TANJA E.
Published: May 2013

In the previous editorial, Larissa van den Herik and Jean d'Aspremont referred to LJIL's ‘special plural identity’. On the one hand, this plurality shows in its table of contents; on the other hand, the plural identity is equally – if not even more – treasured in terms of appreciating the plurality of voices within the legal discipline, as the editors-in-chief also highlight. Diversity and heterogeneity are an asset for academic debate, and LJIL as such seeks to provide a forum for scholars from different ‘paradigms’. The appreciation of diversity and plurality is also reflected in the interest of LJIL to look beyond the confines of the legal discipline itself and engage with external perspectives to foster discussions about international law. It is in light of this open-mindedness and the wish to reach out to non-legal audiences, and to the international relations community in particular, that I was invited to join the LJIL team some years ago. Whereas there is a growing audience of IR scholars genuinely interested in (theorizing) international law, LJIL is not very well known as a journal with that profile for its International Legal Theory section. As a leading scholar in IR once remarked: ‘LJIL is the best kept secret in IR’. So when the request came for me to write an editorial, it seemed only apt to reflect upon some of the perils and promises of interdisciplinarity from my experience as an IR scholar within the LJIL editorial board.
Double aortic arch: postnatal obliteration of the left aortic arch. Is arterial duct closure responsible?
Authors: Rose David , D'Ascoli Riccardo , Ventriglia Flavia , Miraldi Fabio
Published: May 2013

We present a case of double aortic arch with a predominant right and a double arterial duct detected by echocardiogram in a 28-week gestation foetus. The first evaluation revealed that both arches were perfused; the 1-month postnatal echocardiogram showed the closure of both arterial ducts and the partial obliteration of the left aortic arch between the left subclavian artery and the dorsal aorta. In our case, the postnatal obliteration of the left arch in a double aortic arch was probably due to the closure of the left-sided arterial duct.
PTSD in Paramedics: Resilience and Sense of Coherence
Authors: Streb Markus , Häller Pascal , Michael Tanja
Published: May 2013

Background: Paramedics are frequently subjected to traumatic experiences and have higher PTSD prevalence rates than people in the general population. However, the vast majority of paramedics do not develop PTSD. While several risk factors for PTSD have been established, little is known about protective factors. It has been suggested that a good sense of coherence (SOC) and high resilience lower the risk for developing PTSD. Aims: To examine whether SOC and resilience are associated with PTSD severity in paramedics. Method: A cross-sectional study investigated SOC, resilience and PTSD in paramedics (N = 668). PTSD was assessed with the Posttraumatic Stress Diagnostic Scale (PDS); resilience and SOC were measured with the Resilience Scale (RS-11) and the Sense of Coherence Scale (SOC-L9). Further measures included preparation of dealing with traumatic events and availability of psychological help. Results: As expected, both resilience and SOC were negatively correlated with PTSD symptoms. The regression analysis showed that 19.2% of the total variance in symptom severity was explained by these variables. However, SOC was a better predictor than resilience for PTSD severity, as it accounted for more unique variance. Paramedics who were prepared for dealing with work-related traumatic events and who received psychological help had less severe PTSD symptoms and higher SOC scores than paramedics for whom these services were not available. Conclusions: Enhancing resilience, and especially SOC, seems a promising approach to reduce PTSD symptom severity in high risk groups like paramedics.
Cyanobacteria isolated from the high-intertidal zone: a model for studying the physiological prerequisites for survival in low Earth orbit
Authors: Olsson-Francis Karen , Watson Jonathan S. , Cockell Charles S.
Published: May 2013

Cyanobacteria are capable of surviving the adverse conditions of low Earth orbit (LEO). We have previously demonstrated thatGloeocapsastrain OU_20,Chroococcidiopsisand akinetes ofAnabaena cylindricawere able to survive 548 days of exposure to LEO. Motivated by an interest to understand how cyanobacteria can survive in LEO, we studied the strategies thatGloeocapsastrain OU_20 employs to survive in its natural environment, the upper region of the intertidal zone. Here, cyanobacteria are exposed to fluctuations in temperature, UV radiation, desiccation and salinity. We demonstrated that an increase in salinity from 6.5‰ (BG-11 medium) to 35.7‰ (similar to that of seawater), resulted in increased resistance to UV radiation (254 nm), vacuum (0.7×10−3±0.01 kPa) and cold temperatures (–20 °C). Concomitantly, biochemical analyses demonstrated that the amount of fatty acids and mycosporine-like amino acids (a UV absorbing pigment) were higher in the stressed cells. Morphological analysis demonstrated that the electron density and thickness of the mucilaginous sheath were also greater than in the control cells. Yet, the control and stressed cells both formed aggregates. As a result of studying the physiological adaptation ofGloeocapsastrain OU_20 in response to salinity, we postulate that survival in the high-intertidal zone and LEO involves a dense extracellular mucilaginous sheath and the formation of aggregates. We conclude that studying the physiological adaptation of cyanobacteria in the intertidal zone provides insight into understanding survival in LEO.
Nutrient and population dynamics in a subglacial reservoir: a simulation case study of the Blood Falls ecosystem with implications for astrobiology
Authors: Fisher Thomson Mason , Schulze-Makuch Dirk
Published: May 2013

Subglacial ecosystems have recently become of interest within the astrobiological community, as they represent a potentially habitable location in otherwise uninhabitable environments. We used data from Blood Falls, particularly the periodic discharge from the subglacial reservoir beneath Taylor Glacier, Antarctica, to construct an ecosystem model of the putative subglacial microbial community residing there using system dynamics modelling. The model results were, for the most part, within an order of magnitude of the geochemical field data. Productivity was quite low, at 6.4×10−5g carbon l−1yr−1. Based on the results, we draw the following conjectures for the search for life on Mars: A similar ecosystem would require a continual supply of oxidized iron for energy and generate significant amounts of reduced iron as a waste product, be relatively resilient to temporary disturbances, and, thermodynamically, would require at least 0.003 kJ mol l−1of energy to survive at that level of productivity. These results may help to better identify the constraints and boundaries of ecosystems in extreme environments, on Earth and other planetary bodies.
Music Making and the Aging Brain
Authors: Jäncke Lutz
Published: May 2013

The chapter reviews the evidence in support of the idea that cognitive functions can benefit from listening to music or making music and how this evidence might be used to stabilize cognitive aging and prevent or diminish cognitive decline. The beneficial effects are more or less direct (e. g., for auditory perception) or indirect (e. g., for arousal and motivation). The core functions engaged during music listening or music making are executive functions that include attention, working memory, planning, and motor control. These functions are mainly controlled by neural networks located in the frontal cortex, the brain area that undergoes strongest decline in volume with increasing age. In this paper it is argued that this shrinkage of the frontal cortex or the natural course of the decline in frontal brain volume can be counteracted by engaging frontal executive functions through music listening and making. However, current experimental data supporting beneficial effects of music listening and music making is scarce. Therefore, well controlled randomized control group experiments are urgently needed.
Enfants ayant reçu une irradiation de la région cranio-cervico-faciale : évaluation du besoin de traitement orthodontique
Authors: Akharzouz Caroline , Chauty Sarah , Bodard Anne-Gaëlle
Published: May 2013

Introduction : Actuellement, 1 sur 900 adultes âgés de 16 à 44 ans est un survivant d’un cancer de l’enfance. Le taux global de survie pour tous les types de cancers de l’enfance approche des 80 % et les progrès dans le traitement et les soins continuent à offrir des résultats prometteurs. Des années après leur traitement, ces enfants, malgré leurs problèmes de santé chronique, aspirent à avoir, dans la mesure du possible, un accès aux soins orthodontiques à l’instar des enfants en bonne santé. Objectifs : Pour répondre à cette nécessité et aux difficultés thérapeutiques que rencontrent les orthodontistes face à ces patients, nous avons mené une étude transversale épidémiologique au Centre anticancéreux Léon Bérard à Lyon. L’objectif était de recenser les besoins de traitement orthodontique des enfants de plus de 7 ans ayant reçu un traitement antinéoplasique par radiothérapie de la région cranio-cervico-faciale. Résultats : Notre étude conclut que les enfants ayant reçu une irradiation de la région cranio-faciale présentent des retards de croissance, une dissymétrie faciale dans 74 % des cas, un recouvrement et surplomb incisifs augmentés dans respectivement 70 % et 61 % des cas. Les anomalies de développement dentaire sont retrouvées chez 83 % des patients et représentées par des microdonties, des fermetures apicales prématurées et des hypoplasies. Nous retrouvons des troubles trophiques tels que l’hyposialie. Enfin, le besoin de traitement est avéré pour 61 % des patients, modéré dans 17 % des cas; il est lié à l’absence ou rétention de dents et à l’augmentation du surplomb incisif.
SIBSystem : une innovation dans le domaine du collage des attaches orthodontiques?
Authors: Moreau Alexis
Published: May 2013

La mise en place des attaches orthodontiques sur la face vestibulaire des dents a connu deux avancées majeures ces 50 dernières années : le collage direct, d’une part, introduit par Newmann en 1965 et le collage indirect, d’autre part, issu des travaux de Silvermann et Cohen en 1972. Si l’on met de côté les évolutions technologiques des composants du collage (colles et attaches orthodontiques notamment), ces procédures ont finalement peu évolué. Par ailleurs, le collage direct est encore utilisé par une grande majorité des orthodontistes malgré la rapidité, l’ergonomie et la précision apportées par le collage indirect. L’originalité principale du système présenté dans cet article est de permettre de coller les attaches orthodontiques dans une position prédéterminée virtuellement selon un protocole de collage indirect mais avec l’efficacité du collage direct dans la mesure où la colle est directement appliquée sur la base vierge des attaches orthodontiques sans pré-encollage. Cette innovation est rendue possible par l’utilisation des dernières technologies de CFAO. L’article décrit les deux éléments constituant le SIBSystem (SIBTray et SIBClip) et explique les étapes de leur fabrication. L’utilisation clinique est également évoquée de même que les précautions et limites de ce système de collage innovant.
Electronic properties of aluminum/CdZnTe interfaces
Authors: Bai Xuxu , Jie Wanqi , Zha Gangqiang , Zhang Wenhua , Zhu Junfa , Wang Tao , Qian Dong , Liu Ying , Jia Jinfeng
Published: May 2013

Understanding complex correlations between the macroscopic device performance and the contact formation on the atomic level in CdZnTe radiation detectors remains an enormous challenge. In this work, an effort towards bridging that macro-nano knowledge gap is made by systematic study of the electronic structures in the interface of Al/CdZnTe(111)A and Al/CdZnTe(111)B with Al coverage from sub-monolayer to multilayers using photoemission spectroscopy. Remarkable difference of the electronic states was found in these two interfaces. A strong interaction between Al and CdZnTe(111)A was observed at room temperature and thick interface layers (>12 nm) formed. In contrast, an intermix layer with a thickness of about one atomic layer (∼0.3 nm) was formed at Al/CdZnTe(111)B interface.
Effects of alloying and local order in AuNi contacts for Ohmic radio frequency micro electro mechanical systems switches via multi-scale simulation
Authors: Gaddy Benjamin E. , Kingon Angus I. , Irving Douglas L.
Published: May 2013

Ohmic RF-MEMS switches hold much promise for low power wireless communication, but long-term degradation currently plagues their reliable use. Failure in these devices occurs at the contact and is complicated by the fact that the same asperities that bear the mechanical load are also important to the flow of electrical current needed for signal processing. Materials selection holds the key to overcoming the barriers that prevent widespread use. Current efforts in materials selection have been based on the material's (or alloy's) ability to resist oxidation as well as its room-temperature properties, such as hardness and electrical conductivity. No ideal solution has yet been found via this route. This may be due, in part, to the fact that the in-use changes to the local environment of the asperity are not included in the selection criteria. For example, Joule heating would be expected to raise the local temperature of the asperity and impose a non-equilibrium thermal gradient in the same region expected to respond to mechanical actuation. We propose that these conditions should be considered in the selection process, as they would be expected to alter mechanical, electrical, and chemical mechanisms in the vicinity of the surface. To this end, we simulate the actuation of an Ohmic radio frequency micro electro mechanical systems switch by using a multi-scale method to model a current-carrying asperity in contact with a polycrystalline substrate. Our method couples continuum solutions of electrical and thermal transport equations to an underlying molecular dynamics simulation. We present simulations of gold-nickel asperities and substrates in order to evaluate the influence of alloying and local order on the early stages of contact actuation. The room temperature response of these materials is compared to the response of the material when a voltage is applied. Au-Ni interactions are accounted for through modification of the existing Zhou embedded atom method potential. The modified potential more accurately captures trends in high-temperature properties, including the enthalpy of mixing and melting temperatures. We simulate the loading of a contacting asperity to several substrates with varying Ni alloying concentrations and compare solid solution strengthening to a phase-separated system. Our simulations show that Ni concentration and configuration have an important effect on contact area, constriction resistance, thermal profiles, and material transfer. These differences suggest that a substrate with 15 at. % Ni featuring phase segregation has fewer early markers that experimentally have indicated long-term failure.
Isochoric thermal conductivity of solid furan
Authors: Konstantinov V. A. , Sagan V. V. , Revyakin V. P. , Zvonaryova A. V. , Pursky O. I.
Published: May 2013

The thermal conductivity of solid furan samples with different densities has been measured under isochoric conditions in the high-temperature orientationally-disordered phase I. Our isochoric data show a gradual increase of ΛV with temperature, while the isobaric thermal conductivity decreases over this temperature range. This effect shows up more clearly in furan, where the atoms in the ring plane are not equivalent, than in the previously studied C6H6 and C6H12. The increase of ΛV with temperature can be attributed to weakening of the translational-orientational interaction, which in turn leads to reduced phonon scattering on rotational excitations. The experimental data are described in terms of a modified Debye model of thermal conductivity with heat transfer by both low-frequency phonons and “diffuse” modes.
Sound velocities in solid hydrogen under pressure
Authors: Freiman Yu. A. , Grechnev Alexei , Tretyak S. M. , Goncharov Alexander F. , Hemley Russell J.
Published: May 2013

We present results of semi-empirical lattice dynamics calculations of the sound velocities in solid hydrogen under pressure based on the many-body intermolecular potential and first-principle density-functional theory (DFT). Both the sound velocities and elastic moduli are in excellent agreement with data from Brillouin scattering measurements while Silvera–Goldman and Hemley–Silvera–Goldman potentials tend to overestimate the sound velocity. It is shown that the stiffer is the potential the greater is overestimated the sound velocity. As was the case for equation of state and Raman-active lattice phonon calculations, the employed many-body potential works well for phases I and II (up to ∼140 GPa) while for higher pressures the use of the DFT is preferable.