bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical and experimental research on the influence of multiple piezoelectric effects on physical parameters of piezoelectric actuator
Authors: Shi Liping , Zhou Haimin , Huang Jie , Tan Jiliang
Published: March 2015

Compared with the traditional actuator of machinery and electricity, the piezoelectric actuator has the advantages of a compact structure, small volume, no mechanical friction, athermancy and no electromagnetic interference. Therefore, it has high application value in the fields of MEMS, bioengineering, medical science and so on. This article draws conclusions from the influence of multiple piezoelectric effects on the physical parameters (dielectric coefficient, equivalent capacity, energy conversion and piezoelectric coefficient) of piezoelectric actuators. These data from theoretical and experimental research show the following: (1) The rate between the dielectric coefficient of piezoelectric in mechanical freedom and clamping is obtained from the secondary direct piezoelectric effect, which enhances the dielectric property, increases the dielectric coefficient and decreases the coefficient of dielectric isolation; (2) Under external field, En(ex)=E1, exterior stress T = 0, that is to say, under the boundary condition of mechanical freedom, piezoelectric can store electric energy and elasticity, which obtains power density, elastic density and an electromechanical coupling factor; (3) According to the piezoelectric strain Si(1), piezoelectric displacement Dm(2) and piezoelectric strain Si(3) of multiple piezoelectric effects, when the dielectric coefficient of the first converse piezoelectric effect ε33 is 1326 and the dielectric coefficient of the secondary direct piezoelectric effect increases to 3336, the dielectric coefficient of the ceramic chip increases. When the piezoelectric coefficient of the first converse piezoelectric effect d33 is 595 and the piezoelectric coefficient of the secondary direct piezoelectric effect decreases to 240, the piezoelectric coefficient of the ceramic chip will decrease. It is of major significance both in the applications and in basic theory to research the influence of multiple piezoelectric effects on the physical parameters of piezoelectric actuators. On the one hand, this can further increase the control precision of piezoelectric actuators. On the other hand, it can be applied to research on the physical parameters and self-sensing actuators, like piezoelectric quartz and piezoelectric ceramic self-sensing actuators, which will be of great service for MEMS.
Dramatic enhancement of 1.54 μm emission in Er doped GaN quantum well structures
Authors: Al tahtamouni T. M. , Stachowicz M. , Li J. , Lin J. Y. , Jiang H. X.
Published: March 2015

Erbium (Er) doped III-nitride materials have attracted much attention due to their capability to provide highly thermal stable optical emission in the technologically important as well as eye-safer 1540 nm wavelength window. There is a continued need to exploring effective mechanisms to further improve the quantum efficiency (QE) of the 1.54 μm emission in Er-doped III-nitrides. GaN/AlN multiple quantum wells (MQWs:Er) have been synthesized by metal organic chemical vapor deposition and explored as an effective means to improve the QE of the 1.54 μm emission via carrier confinement and strain engineering. The 1.54 μm emission properties from MQWs:Er were probed by photoluminescence (PL) emission spectroscopy. It was found that the emission intensity from MQWs:Er is 9 times higher than that of GaN:Er epilayers with a comparable Er active layer thickness. The influences of the well and barrier width on the PL emission at 1.54 μm were studied. The results revealed that MQWs:Er consisting of well width between 1 and 1.5 nm and the largest possible barrier width before reaching the critical thickness provide the largest boost in QE of the 1.54 μm emission. These results demonstrate that MQWs:Er provide a basis for efficient photonic devices active at 1.54 μm.
Density and x-ray emission profile relationships in highly ionized high-Z laser-produced plasmas
Authors: Yoshida Kensuke , Fujioka Shinsuke , Higashiguchi Takeshi , Ugomori Teruyuki , Tanaka Nozomi , Kawasaki Masato , Suzuki Yuhei , Suzuki Chihiro , Tomita Kentaro , Hirose Ryoichi , Ejima Takeo , Ohashi Hayato , Nishikino Masaharu , Sunahara Atsushi , Li Bowen , Dunne Padraig , O'Sullivan Gerry , Yanagida Tatsuya , Azechi Hiroshi , Nishimura Hiroaki
Published: March 2015

We present a benchmark measurement of the electron density profile in the region where the electron density is 1019 cm–3 and where the bulk of extreme ultraviolet (EUV) emission occurs from isotropically expanding spherical high-Z gadolinium plasmas. It was found that, due to opacity effects, the observed EUV emission is mostly produced from an underdense region. We have analyzed time-resolved emission spectra with the aid of atomic structure calculations and find the multiple ion charge states around 18+ during the laser pulse irradiation.
Direct probing of electron and hole trapping into nano-floating-gate in organic field-effect transistor nonvolatile memories
Authors: Cui Ze-Qun , Wang Shun , Chen Jian-Mei , Gao Xu , Dong Bin , Chi Li-Feng , Wang Sui-Dong
Published: March 2015

Electron and hole trapping into the nano-floating-gate of a pentacene-based organic field-effect transistor nonvolatile memory is directly probed by Kelvin probe force microscopy. The probing is straightforward and non-destructive. The measured surface potential change can quantitatively profile the charge trapping, and the surface characterization results are in good accord with the corresponding device behavior. Both electrons and holes can be trapped into the nano-floating-gate, with a preference of electron trapping than hole trapping. The trapped charge quantity has an approximately linear relation with the programming/erasing gate bias, indicating that the charge trapping in the device is a field-controlled process.
The
frequency
natural antisense transcript first promotes, then represses,
frequency
gene expression via facultative heterochromatin
Authors: Li Na , Joska Tammy M. , Ruesch Catherine E. , Coster Samuel J. , Belden William J.
Published: March 2015

Significance

The circadian clock is predominantly regulated by transcriptional negative feedback, where the protein(s) arising from the central clock gene(s) inhibit their own expression. In
Neurospora
and mammals, the clock genes have natural antisense transcripts (NATs): long noncoding RNAs that overlap and are expressed in opposite orientation to the protein coding genes. Previously, we demonstrated that
Neurospora frequency
NAT is needed for normal DNA methylation. This report demonstrates that proper regulation of the
frequency
antisense transcript is needed to establish repressive heterochromatin. However, prior to establishing heterochromatin, NAT expression creates a transcriptionally permissive state that helps promote sense transcript expression. Broader implications indicate that NATs, in general, may first promote sense gene expression prior to establishing heterochromatin.
Systematic identification of signal integration by protein kinase A
Authors: Filteau Marie , Diss Guillaume , Torres-Quiroz Francisco , Dubé Alexandre K. , Schraffl Andrea , Bachmann Verena A. , Gagnon-Arsenault Isabelle , Chrétien Andrée-Ève , Steunou Anne-Lise , Dionne Ugo , Côté Jacques , Bisson Nicolas , Stefan Eduard , Landry Christian R.
Published: March 2015

Significance

Protein kinase A (PKA) complexes are versatile signaling enzymes controlling homeostasis in eukaryotes. This enzyme is involved in multiple functions under physiological and pathological conditions in humans and governs the virulence of many pathogenic fungi. Here we systematically identify PKA regulators in yeast. Notably, we describe signaling to PKA that involves feedback from the cellular recycling process, autophagy. We also uncover a posttranslational modification, acetylation, that regulates PKA activity in both yeast and mammals, and we show that this mechanism impacts aging. Thus, we identify what regulates PKA as a first step toward the ability to cure diseases and infections, for instance, by providing new candidate genes for drug targeting in health research and antifungals for agricultural and medical purposes.
The uncertain climate footprint of wetlands under human pressure
Authors: Petrescu Ana Maria Roxana , Lohila Annalea , Tuovinen Juha-Pekka , Baldocchi Dennis D. , Desai Ankur R. , Roulet Nigel T. , Vesala Timo , Dolman Albertus Johannes , Oechel Walter C. , Marcolla Barbara , Friborg Thomas , Rinne Janne , Matthes Jaclyn Hatala , Merbold Lutz , Meijide Ana , Kiely Gerard , Sottocornola Matteo , Sachs Torsten , Zona Donatella , Varlagin Andrej , Lai Derrick Y. F. , Veenendaal Elmar , Parmentier Frans-Jan W. , Skiba Ute , Lund Magnus , Hensen Arjan , van Huissteden Jacobus , Flanagan Lawrence B. , Shurpali Narasinha J. , Grünwald Thomas , Humphreys Elyn R. , Jackowicz-Korczyński Marcin , Aurela Mika A. , Laurila Tuomas , Grüning Carsten , Corradi Chiara A. R. , Schrier-Uijl Arina P. , Christensen Torben R. , Tamstorf Mikkel P. , Mastepanov Mikhail , Martikainen Pertti J. , Verma Shashi B. , Bernhofer Christian , Cescatti Alessandro
Published: March 2015

Significance

Wetlands are unique ecosystems because they are in general sinks for carbon dioxide and sources of methane. Their climate footprint therefore depends on the relative sign and magnitude of the land–atmosphere exchange of these two major greenhouse gases. This work presents a synthesis of simultaneous measurements of carbon dioxide and methane fluxes to assess the radiative forcing of natural wetlands converted to agricultural or forested land. The net climate impact of wetlands is strongly dependent on whether they are natural or managed. Here we show that the conversion of natural wetlands produces a significant increase of the atmospheric radiative forcing. The findings suggest that management plans for these complex ecosystems should carefully account for the potential biogeochemical effects on climate.
Sparse feature selection methods identify unexpected global cellular response to strontium-containing materials
Authors: Autefage Hélène , Gentleman Eileen , Littmann Elena , Hedegaard Martin A. B. , Von Erlach Thomas , O’Donnell Matthew , Burden Frank R. , Winkler David A. , Stevens Molly M.
Published: March 2015

Significance

Although new-generation biomaterials are increasingly complex and sophisticated, their development remains largely empirical, and functional outcomes are difficult to predict. Extending the biological evaluation of biomaterials beyond the assessment of preassumed effects would allow a better understanding of the material-driven cell responses. Here we illustrate how applying an objective, nondiscriminative approach to explore the global cell responses to a series of bone substitutes with various compositions can uncover unexpected, important changes at the gene and cellular levels and can provide in-depth knowledge of the effects of specific material properties on cell behavior.
An ancestral bacterial division system is widespread in eukaryotic mitochondria
Authors: Leger Michelle M. , Petrů Markéta , Žárský Vojtěch , Eme Laura , Vlček Čestmír , Harding Tommy , Lang B. Franz , Eliáš Marek , Doležal Pavel , Roger Andrew J.
Published: March 2015

Bacterial division initiates at the site of a contractile Z-ring composed of polymerized FtsZ. The location of the Z-ring in the cell is controlled by a system of three mutually antagonistic proteins, MinC, MinD, and MinE. Plastid division is also known to be dependent on homologs of these proteins, derived from the ancestral cyanobacterial endosymbiont that gave rise to plastids. In contrast, the mitochondria of model systems such as
Saccharomyces cerevisiae
, mammals, and
Arabidopsis thaliana
seem to have replaced the ancestral α-proteobacterial Min-based division machinery with host-derived dynamin-related proteins that form outer contractile rings. Here, we show that the mitochondrial division system of these model organisms is the exception, rather than the rule, for eukaryotes. We describe endosymbiont-derived, bacterial-like division systems comprising FtsZ and Min proteins in diverse less-studied eukaryote protistan lineages, including jakobid and heterolobosean excavates, a malawimonad, stramenopiles, amoebozoans, a breviate, and an apusomonad. For two of these taxa, the amoebozoan
Dictyostelium purpureum
and the jakobid
Andalucia incarcerata
, we confirm a mitochondrial localization of these proteins by their heterologous expression in
Saccharomyces cerevisiae
. The discovery of a proteobacterial-like division system in mitochondria of diverse eukaryotic lineages suggests that it was the ancestral feature of all eukaryotic mitochondria and has been supplanted by a host-derived system multiple times in distinct eukaryote lineages.
KLHL3 regulates paracellular chloride transport in the kidney by ubiquitination of claudin-8
Authors: Gong Yongfeng , Wang Jinzhi , Yang Jing , Gonzales Ernie , Perez Ronaldo , Hou Jianghui
Published: March 2015

Significance

The role of tight junction permeability in causing human diseases is an important but understudied area. Here, we discovered a previously unidentified mechanism in the kidney that uses the Kelch-like 3-dependent ubiquitination pathway to regulate claudin-8 and the paracellular permeability to chloride. The importance of posttranslational regulation of tight junction structure and function is shown here, with emphasis on its potential role in causing human hypertension if a proper ubiquitination pathway is disrupted by genetic mutations. Such a mechanism may also be explored as a pharmacologic tool to correct tight junction permeability defects and related diseases.
Trichodesmium
genome maintains abundant, widespread noncoding DNA in situ, despite oligotrophic lifestyle
Authors: Walworth Nathan , Pfreundt Ulrike , Nelson William C. , Mincer Tracy , Heidelberg John F. , Fu Feixue , Waterbury John B. , Glavina del Rio Tijana , Goodwin Lynne , Kyrpides Nikos C. , Land Miriam L. , Woyke Tanja , Hutchins David A. , Hess Wolfgang R. , Webb Eric A.
Published: March 2015

Significance

The free-living cyanobacterium
Trichodesmium
is a major source of new nitrogen and fixed carbon to the tropical and subtropical oceans, but despite its importance, we know little about the molecular mechanisms it uses to succeed in its oligotrophic habitat. Here we show that its gene-sparse genome is littered with large, conserved, expressed intergenic spaces, which is atypical for most known free-living prokaryotes. Paradoxically, although its genome is enriched in predicted transposases and repeat sequences, it exhibits conserved intragenus synteny and similar intergenic architecture relative to its sympatric, gene-dense relatives
Prochlorococcus
and
Synechococcus
. This observation demonstrates a successful alternative to the genomic streamlining strategy observed in other free-living oligotrophs such as
Prochlorococcus
or
Pelagibacter
.
An adenosine triphosphate-independent proteasome activator contributes to the virulence of
Mycobacterium tuberculosis
Authors: Jastrab Jordan B. , Wang Tong , Murphy J. Patrick , Bai Lin , Hu Kuan , Merkx Remco , Huang Jessica , Chatterjee Champak , Ovaa Huib , Gygi Steven P. , Li Huilin , Darwin K. Heran
Published: March 2015

Significance

The proteasome of
Mycobacterium tuberculosis
is required to cause lethal infections and is thus a potential drug target. Bacterial proteasomes degrade proteins modified by pupylation, but evidence suggests that the
M. tuberculosis
proteasome possesses additional functions. In this work, we describe a degradation pathway in
M. tuberculosis
controlled by a previously unidentified proteasomal cofactor, Rv3780. Rv3780 enhanced the ATP-independent proteasomal degradation of peptides and proteins and was required to maintain levels of a unique set of putative proteasome substrates. Importantly, an Rv3780 mutant was attenuated for growth in mice. To our knowledge, these studies show for the first time that an ATP-independent proteasomal-degradation pathway plays a role in the physiology of an important human pathogen.
Criticality of metals and metalloids
Authors: Graedel T. E. , Harper E. M. , Nassar N. T. , Nuss Philip , Reck Barbara K.
Published: March 2015

Significance

In the past decade, sporadic shortages of metals and metalloids crucial to modern technology have inspired attempts to determine the relative “criticality” of various materials as a guide to materials scientists and product designers. The variety of methodologies that have been used for this purpose have (predictably) resulted in widely varying results, which are therefore of little use. In the present study, we develop a comprehensive, flexible, and transparent approach that we apply to 62 metals and metalloids. We find that the metals of most concern tend to be those with three characteristics: they are available largely or entirely as byproducts, they are used in small quantities for highly specialized applications, and they possess no effective substitutes.
TCR contact residue hydrophobicity is a hallmark of immunogenic CD8+T cell epitopes
Authors: Chowell Diego , Krishna Sri , Becker Pablo D. , Cocita Clément , Shu Jack , Tan Xuefang , Greenberg Philip D. , Klavinskis Linda S. , Blattman Joseph N. , Anderson Karen S.
Published: March 2015

Significance

The design of effective T-cell vaccines against pathogens and tumor antigens is challenged by the highly inefficient identification of the subset of peptides from a given antigen that effectively stimulate an immune response. Here we report that the relative hydrophobicity of T-cell receptor contact residues is markedly enriched in immunogenic major histocompatibility complex class I epitopes in both human and murine MHCs, and in both self and pathogen-derived immunogenic epitopes. Incorporating hydrophobicity into T-cell epitope prediction models increases the efficiency of epitope identification, which will manifest in the time and cost of T-cell vaccine development. Amino acid hydrophobicity may represent a biochemical basis by which T cells discriminate immunogenic epitopes within the background of self peptides.
Infection by
Toxoplasma gondii
, a severe parasite in neonates and AIDS patients, causes impaired anion secretion in airway epithelia
Authors: Guo Hong-Mei , Gao Jiang-Mei , Luo Yu-Li , Wen Yan-Zi , Zhang Yi-Lin , Hide Geoff , Zhou Wen-Liang , Ayala Francisco J. , Lun Zhao-Rong
Published: March 2015

Significance

The airway epithelia modulate the inflammatory responses to various pathogens. Pulmonary disease caused by
Toxoplasma gondii
infection affects human neonates, children, and immunocompromised individuals. However, it is not clear how
T. gondii
infection impacts airway epithelia. We report the use of a short-circuit current (
I
sc
) technique to determine the Cl
−
secretion induced by ATP in tracheal epithelia infected by
T. gondii.
We surprisingly found that the ATP-evoked Cl
−
secretion in
T. gondii
-infected mouse tracheal epithelia was significantly suppressed. We also found that the mRNA expression level of the P2Y2 receptor increased significantly in
T. gondii
-infected mouse trachea, via real-time quantitative PCR. Our study provides previously unidentified insights into the mechanism underlying host impairment caused by
T. gondii
infection.
Single-molecule analysis of RAG-mediated V(D)J DNA cleavage
Authors: Lovely Geoffrey A. , Brewster Robert C. , Schatz David G. , Baltimore David , Phillips Rob
Published: March 2015

Significance

V(D)J recombination is essential for assembling immunoglobulin and T-cell receptor genes. The lymphoid-specific RAG recombinase proteins (RAG1 and RAG2) perform DNA cleavage at recombination signal sequences (RSSs) during V(D)J recombination. Although RAG-mediated DNA cleavage has been analyzed in bulk, it has not at the single-molecule level. We used singly tethered DNA particle motion to examine the process in real time. We have found that RAG–RSS binding is reversible, with measurable dwell times before release. We also directly observed a reversible synaptic complex before RAG-mediated hairpin formation and measured its dwell time. These biochemical findings are compatible with a model for V(D)J recombination in vivo, in which the RAG recombinase often samples multiple partner RSSs before initiating the V(D)J recombination reaction.
Evidence for tunneling in base-catalyzed isomerization of glyceraldehyde to dihydroxyacetone by hydride shift under formose conditions
Authors: Cheng Liang , Doubleday Charles , Breslow Ronald
Published: March 2015

Significance

This paper describes experimental and computational evidence that the hydride shift that converts glyceraldehyde to dihydroxyacetone at basic pH with Ca
2+
catalysis proceeds primarily by quantum tunneling. This answers the last question about the mechanism of the formose reaction, in which formaldehyde is converted to higher sugars under these conditions. This reaction has long been seen as an important clue to the formation of molecules needed for life under prebiotic conditions on Earth. Earlier work showed that the mechanism involved a hydride shift, not a deprotonation, and this work confirms those conclusions. It shows the critical role of tunneling, a quantum effect important in chemistry and biology, and in likely prebiotic reactions on Earth or elsewhere, one concern of astrobiology.
Archaic Argument: Aristotle’s Rhetoric and the Problem of First Principles
Authors: Jasso John J.
Published: March 2015

Among Aristotle’s arts of argumentation, two are directly linked to archai, or first principles. Analytic deduces from them and dialectic tests their veracity. This article situates rhetoric as likewise useful for philosophical investigation in Aristotle’s own system by demonstrating how the Rhetoric assigns to rhetorical practice attributes that are uniquely related to the archai—without which investigations into and based on them would be impossible. That is, given the primary nature of the first principles as described by Aristotle, the strategic use of metaphor is the only intellectual machinery he has for articulating, disseminating, and gaining acquiescence for them.
Marine Distribution and Habitat Use of Atlantic Sturgeon in New York Lead to Fisheries Interactions and Bycatch
Authors: Dunton Keith J. , Jordaan Adrian , Conover David O. , McKown Kim A. , Bonacci Lisa A. , Frisk Michael G.
Published: March 2015

Population declines of Atlantic Sturgeon Acipenser oxyrinchus oxyrinchus prompted initial fisheries closures and an eventual endangered or threatened species listing across the U.S. portion of their range in 2012. Atlantic Sturgeon aggregations and migration routes along the coast of Long Island overlap with commercial fishing activities that may lead to incidental take in nondirected fisheries. Thus, understanding the distribution and movement of Atlantic Sturgeon in relation to commercial fisheries can help management agencies determine impacts and develop bycatch mitigation measures. Stratified random sampling and targeted bottom trawl surveys were used to identify the temporal and spatial use of marine habitat in New York waters. The majority of survey captures were restricted to depths of less than 15 m and known aggregation areas. During the aggregation periods (May, June, September, and October) in known aggregation areas, catches were an order of magnitude higher than in other areas and months of the year. Northeast Fisheries Observer Program bycatch data from 1989 to 2013 was analyzed for the New York region and suggested that bycatch occurs within two main gear types: otter bottom trawls and sink gill nets. Trawling bycatch contained primarily subadult Atlantic Sturgeon and is highest during the Summer Flounder Paralichthys dentatus fishery in New York State waters. Trawling overlaps spatially and temporally with identified Atlantic Sturgeon aggregation areas, while bycatch in gill nets targeted adult fish farther offshore in federal waters. Bycatch in these fisheries may be a regional threat to recovery, and spatial and temporal closures, gear modifications, or other bycatch reduction techniques are suggested to protect aggregating and migrating fish.

Received July 28, 2014; accepted November 4, 2014
Scholarly article seeking, reading, and use: a continuing evolution from print to electronic in the sciences and social sciences
Authors: TENOPIR Carol , KING Donald W. , CHRISTIAN Lisa , VOLENTINE Rachel
Published: March 2015

Electronic journals are now the norm for accessing and reading scholarly articles. This article examines scholarly article reading patterns by faculty in five US universities in 2012. Selected findings are also compared to some general trends from studies conducted periodically since 1977. In the 2012 survey, over three‐quarters (76%) of the scholarly readings were obtained through electronic means and just over half (51%) of readings were read on a screen rather than from a print source or being printed out. Readings from library sources are overwhelmingly from e‐sources. The average number of articles read per month was 20.66, with most articles read by the medical and other sciences, and on average each article was read for 32 minutes.
Beyond authorship: attribution, contribution, collaboration, and credit
Authors: Brand Amy , Allen Liz , Altman Micah , Hlava Marjorie , Scott Jo
Published: March 2015

Key points

As the number of authors on scientific publications increases, ordered lists of author names are proving inadequate for the purposes of attribution and credit.

A multi‐stakeholder group has produced a contributor role taxonomy for use in scientific publications.

Identifying specific contributions to published research will lead to appropriate credit, fewer author disputes, and fewer disincentives to collaboration and the sharing of data and code.
Poincaré duality for Ext–groups between strict polynomial functors
Authors: Chałupnik Marcin
Published: March 2015

We study the relation between left and right adjoint functors to the precomposition functor. As a consequence, we obtain various dualities for the Ext–groups in the category of strict polynomial functors.
Quantitative analysis of three-dimensional fibrillar collagen microstructure within the normal, aged and glaucomatous human optic nerve head
Authors: Jones H. J. , Girard M. J. , White N. , Fautsch M. P. , Morgan J. E. , Ethier C. R. , Albon J.
Published: March 2015

The aim of this study was to quantify connective tissue fibre orientation and alignment in young, old and glaucomatous human optic nerve heads (ONH) to understand ONH microstructure and predisposition to glaucomatous optic neuropathy. Transverse (seven healthy, three glaucomatous) and longitudinal (14 healthy) human ONH cryosections were imaged by both second harmonic generation microscopy and small angle light scattering (SALS) in order to quantify preferred fibre orientation (PFO) and degree of fibre alignment (DOFA). DOFA was highest within the peripapillary sclera (ppsclera), with relatively low values in the lamina cribrosa (LC). Elderly ppsclera DOFA was higher than that in young ppsclera (
p
< 0.00007), and generally higher than in glaucoma ppsclera. In all LCs, a majority of fibres had preferential orientation horizontally across the nasal–temporal axis. In all glaucomatous LCs, PFO was significantly different from controls in a minimum of seven out of 12 LC regions (
p
< 0.05). Additionally, higher fibre alignment was observed in the glaucomatous inferior–temporal LC (
p
< 0.017). The differences between young and elderly ONH fibre alignment within regions suggest that age-related microstructural changes occur within the structure. The additional differences in fibre alignment observed within the glaucomatous LC may reflect an inherent susceptibility to glaucomatous optic neuropathy, or may be a consequence of ONH remodelling and/or collapse.
Toxicity and medical countermeasure studies on the organophosphorus nerve agents VM and VX
Authors: Rice Helen , Dalton Christopher H. , Price Matthew E. , Graham Stuart J. , Green A. Christopher , Jenner John , Groombridge Helen J. , Timperley Christopher M.
Published: March 2015

To support the effort to eliminate the Syrian Arab Republic chemical weapons stockpile safely, there was a requirement to provide scientific advice based on experimentally derived information on both toxicity and medical countermeasures (MedCM) in the event of exposure to VM, VX or VM–VX mixtures. Complementaryin vitroandin vivostudies were undertaken to inform that advice. The penetration rate of neat VM was not significantly different from that of neat VX, through either guinea pig or pig skinin vitro. The presence of VX did not affect the penetration rate of VM in mixtures of various proportions. A lethal dose of VM was approximately twice that of VX in guinea pigs poisoned via the percutaneous route. There was no interaction in mixed agent solutions which altered thein vivotoxicity of the agents. Percutaneous poisoning by VM responded to treatment with standard MedCM, although complete protection was not achieved.
A heuristic for the distribution of point counts for random curves over a finite field
Authors: Achter Jeffrey D. , Erman Daniel , Kedlaya Kiran S. , Wood Melanie Matchett , Zureick-Brown David
Published: March 2015

How many rational points are there on a random algebraic curve of large genus
g
over a given finite field

? We propose a heuristic for this question motivated by a (now proven) conjecture of Mumford on the cohomology of moduli spaces of curves; this heuristic suggests a Poisson distribution with mean
q
+1+1/(
q
−1). We prove a weaker version of this statement in which
g
and
q
tend to infinity, with
q
much larger than
g
.
Novel crystalline phase and first-order phase transitions of human insulin complexed with two distinct phenol derivatives
Authors: Valmas A. , Magiouf K. , Fili S. , Norrman M. , Schluckebier G. , Beckers D. , Degen T. , Wright J. , Fitch A. , Gozzo F. , Giannopoulou A. E. , Karavassili F. , Margiolaki I.
Published: March 2015

The primary focus of the present work is the study of the effects that two ligands and the crystallization pH have on the crystalline forms of human insulin. For this purpose, human insulin (HI) was co-crystallized with two distinct phenolic derivatives: the organic ligandsmeta-cresol (m-cresol) and 4-nitrophenol. The formation of polycrystalline precipitates was then followed by means of structural characterization of the individual specimens in terms of unit-cell symmetry and parameters. In both cases, two different polymorphs were identifiedviaX-ray powder diffraction measurements, the first of hexagonal symmetry (R3 space group) at higher pH values and the second of monoclinic symmetry (space groupP21) with unit-cell parametersa= 87.4282 (5),b = 70.5020 (3),c= 48.3180 (4) Å, β = 106.8958 (4)°, the latter of which to our knowledge has never been observed before.
A covalent adduct of MbtN, an acyl-ACP dehydrogenase fromMycobacterium tuberculosis, reveals an unusual acyl-binding pocket
Authors: Chai Ai-Fen , Bulloch Esther M. M. , Evans Genevieve L. , Lott J. Shaun , Baker Edward N. , Johnston Jodie M.
Published: March 2015

Mycobacterium tuberculosis(Mtb) is the causative agent of tuberculosis. Access to iron in host macrophages depends on iron-chelating siderophores called mycobactins and is strongly correlated withMtbvirulence. Here, the crystal structure of anMtbenzyme involved in mycobactin biosynthesis, MbtN, in complex with its FAD cofactor is presented at 2.30 Å resolution. The polypeptide fold of MbtN conforms to that of the acyl-CoA dehydrogenase (ACAD) family, consistent with its predicted role of introducing a double bond into the acyl chain of mycobactin. Structural comparisons and the presence of an acyl carrier protein, MbtL, in the same gene locus suggest that MbtN acts on an acyl-(acyl carrier protein) rather than an acyl-CoA. A notable feature of the crystal structure is the tubular density projecting from N(5) of FAD. This was interpreted as a covalently bound polyethylene glycol (PEG) fragment and resides in a hydrophobic pocket where the substrate acyl group is likely to bind. The pocket could accommodate an acyl chain of 14–21 C atoms, consistent with the expected length of the mycobactin acyl chain. Supporting this, steady-state kinetics show that MbtN has ACAD activity, preferring acyl chains of at least 16 C atoms. The acyl-binding pocket adopts a different orientation (relative to the FAD) to other structurally characterized ACADs. This difference may be correlated with the apparent ability of MbtN to catalyse the formation of an unusualcisdouble bond in the mycobactin acyl chain.
Setting new trends of integrated Building Information Modelling (BIM) for construction industry
Authors: Wang Xiangyu , Chong Heap-Yih
Published: March 2015

Purpose

– The purpose of this paper is to set new trends of integrated Building Information Modelling (BIM) for the construction industry. BIM has been accepted by construction to some extent as an innovative approach/technology to improve project performance in the aspects of productivity, efficiency and safety. However, maximisation BIM requires strategic research direction to drive this technology across the full spectrum of the project life cycle.

Design/methodology/approach

– This paper identifies the new trends for adopting BIM in the aspect of integration within Architecture, Engineering and Construction (AEC) sectors.

Findings

– Research findings identify three stages where project performance can be improved by using BIM: pre-construction phase, construction phase and the maintenance/operation phase.

Originality/value

– BIM must evolve to be fully integrated with other technologies, thereby contributing to project performance in various stages of project life cycle.
Preparation and scheduling system of emergency supplies in disasters
Authors: Jia Liu , Kefan Xie
Published: March 2015

Purpose

– After the occurrence of a disaster, emergency supplies should arrive at disaster area in the shortest possible time. Therefore, it is of pivotal importance to speed up the preparation and scheduling process. In other words, only when the preparation process and scheduling process coordinate well, could the emergency supplies arrive at disaster area in time. Consequently, the purpose of this paper is to explore a method that can strengthen the coordination in various kinds of situations.

Design/methodology/approach

– The paper first elaborates the preparation and scheduling process of emergency supplies in disasters. Then, it establishes a workflow simulation system of the emergency supplies preparation and scheduling based on Petri Net. Afterward, the paper proposes a simplified simulation system of emergency supplies preparation and scheduling which can be employed in actual emergency response. Finally, the paper takes China Lushan Earthquake for a case study.

Findings

– By employing the simulation system proposed by this paper, decision makers can simulate the whole emergency supplies preparation and scheduling process, which can help them find a method that can optimize the current process. Specifically, by analyzing the simulation results, the government can obtain conclusions as follows. First, whether the preparation and scheduling process of emergency supplies can speed up or not. Second, which part of the process should be improved to realize the acceleration. Third, the workload of the staffs and experts. Fourth, whether it is necessary to add staffs or experts to work in parallel.

Originality/value

– This paper proposes a system that can coordinate the preparation process and scheduling process of emergency supplies in disaster. Then, it employs the Petri Net based workflow model to do simulation. The simulation results show that the system designed is reasonable and can be used in practical decision making on the preparation and scheduling of emergency supplies.
The influence of corporate social responsibility disclosure on share prices
Authors: De Klerk Marna , de Villiers Charl , van Staden Chris
Published: March 2015

Purpose

– The purpose of this paper is to examine the association between share prices and the level of corporate social responsibility (CSR) disclosure of large UK companies, using CSR data from an independent firm and a time period and setting (the UK) that coincides with increased legislation and increased public awareness of corporate social and environmental issues. Against a background of increased interest by investors in CSR disclosure, prior mixed results on the association between CSR disclosure and share prices suggest the need for further research that overcome some of the identified limitations of the extant literature.

Design/methodology/approach

– A modified Ohlson (1995) model is used to examine the relationship between CSR disclosure and share prices among the 100 largest UK companies. Three different measures of CSR disclosure are used to ensure robustness of results.

Findings

– The paper finds that higher levels of CSR disclosure are associated with higher share prices. Furthermore, the paper provides evidence that CSR disclosure by companies operating in environmentally sensitive industries show a stronger association with share prices than CSR disclosure by companies operating in other industries. The paper concludes that CSR disclosure provides incremental value-relevant information to investors beyond financial accounting information.

Originality/value

– To the best of our knowledge, this is the first paper to provide evidence of the incremental value of CSR disclosure to share price determination in the UK, a country where CSR disclosure is high on the agenda. Our findings provide evidence that CSR disclosures by companies and, in particular, disclosures following the global reporting initiative(GRI) guidelines, are useful to investors and shareholders, as it is related to share price information.
Accreditation and quality assurance in the Egyptian higher education system
Authors: Schomaker Rahel
Published: March 2015

Purpose

– This study aims to analyze the quality of the Egyptian accreditation system. With a view on the high competition in the domestic labor market as well as with regards to the international competitiveness of Egyptian graduates and the potential role of Egyptian universities in the international market for higher education, a high quality of study programmes and the provision of skills which meet the employers’ needs is a pressing issue for policymakers in Egypt, in particular in the light of the recent and ongoing transformation process.

Design/methodology/approach

– Based on a triangulation of document analysis and semi-structured interviews, the authors analyze the strengths and weaknesses of the system of accreditation as well as current measures to improve quality in higher education and provide policy implications for further action undertaken by Egyptian policymakers to improve the accreditation system.

Findings

– First, the authors provide a sound overview of the newly established accreditation system in Egypt and analyze the role of the National Authority of Educational Quality Assurance and Accreditation within this process. Second, the paper addresses the structural shortcomings as well as implementation problems of the current accreditation system which limit the capacity of the national accreditation agency to provide accreditation for all institutions of higher education in Egypt and to ensure the overall quality of higher education. The role of peer reviewers is of pivotal importance in this context. A specific problem which has not been analyzed so far is the role of religious institutions, the so-called Al-Azhar institutions, in the accreditation process, and the consequences this will have for further developments in accreditation.

Practical implications

– The paper concludes with providing policy implications at the backdrop of the ongoing political transformation process in Egypt.

Originality/value

– The paper provides the first comprehensive analysis of the strengths and weaknesses of the Egyptian accreditation system and contributes to the understanding of the pivotal role of peer reviewers in this process. Also, for the first time, the challenges regarding accreditation of Al-Azhar institutions are targeted.
Investigating and compensating printed circuit board shrinkage induced failures during reflow soldering
Authors: Geczy Attila , Fejos Márta , Tersztyánszky László
Published: March 2015

Purpose

– This paper aims to reveal the causes and find an efficient method to compensate the shrinkage to reduce failure costs. Reflow-induced printed circuit board (PCB) shrinkage is inspected in automotive electronics production environment. The shrinkage of two-sided, large PCBs results in printing offset errors and consequently soldering failures on smaller components during the reflow soldering of the second PCB side.

Design/methodology/approach

– During the research, the investigations had to adapt to actual production in an electronics manufacturing plant. A measurement method was developed to approximate the overall shrinkage of the given product. With the shrinkage data, it is possible to perform an efficient compensation on the given stencil design in computer-aided manufacturing environment.

Findings

– It was found that even with the investigated lower-quality PCB materials, the compensation on the stencil significantly reduces the quantity of failures, offering an efficient method to improve the yield of the production.

Research limitations/implications

– Research was oriented by the confines of production (fixed PCB sources, given PCB materials, reflow process and production line), where an immediate solution is needed. Future investigations should be focussed on the PCB parameters (different epoxy types, glass-fibre reinforcements, etc.).

Practical implications

– The optimised production reduces overall failure costs. The stencil re-design and application is a fast and efficient way to immediately act against the shrinkage-induced failures. The method was successfully applied in automotive electronics production.

Originality/value

– The paper presents a novel approach on solving an emerging problem during reflow.
REVIEW: Wildlife camera trapping: a review and recommendations for linking surveys to ecological processes
Authors: Burton A. Cole , Neilson Eric , Moreira Dario , Ladle Andrew , Steenweg Robin , Fisher Jason T. , Bayne Erin , Boutin Stan
Published: March 2015

Reliable assessment of animal populations is a long‐standing challenge in wildlife ecology. Technological advances have led to widespread adoption of camera traps (CTs) to survey wildlife distribution, abundance and behaviour. As for any wildlife survey method, camera trapping must contend with sources of sampling error such as imperfect detection. Early applications focused on density estimation of naturally marked species, but there is growing interest in broad‐scale CT surveys of unmarked populations and communities. Nevertheless, inferences based on detection indices are controversial, and the suitability of alternatives such as occupancy estimation is debatable.

We reviewed 266 CT studies published between 2008 and 2013. We recorded study objectives and methodologies, evaluating the consistency of CT protocols and sampling designs, the extent to which CT surveys considered sampling error, and the linkages between analytical assumptions and species ecology.

Nearly two‐thirds of studies surveyed more than one species, and a majority used response variables that ignored imperfect detection (e.g. presence–absence, relative abundance). Many studies used opportunistic sampling and did not explicitly report details of sampling design and camera deployment that could affect conclusions.

Most studies estimating density used capture–recapture methods on marked species, with spatially explicit methods becoming more prominent. Few studies estimated density for unmarked species, focusing instead on occupancy modelling or measures of relative abundance. While occupancy studies estimated detectability, most did not explicitly define key components of the modelling framework (e.g. a site) or discuss potential violations of model assumptions (e.g. site closure). Studies using relative abundance relied on assumptions of equal detectability, and most did not explicitly define expected relationships between measured responses and underlying ecological processes (e.g. animal abundance and movement).

Synthesis and applications. The rapid adoption of camera traps represents an exciting transition in wildlife survey methodology. We remain optimistic about the technology's promise, but call for more explicit consideration of underlying processes of animal abundance, movement and detection by cameras, including more thorough reporting of methodological details and assumptions. Such transparency will facilitate efforts to evaluate and improve the reliability of camera trap surveys, ultimately leading to stronger inferences and helping to meet modern needs for effective ecological inquiry and biodiversity monitoring.
The international diffusion of electoral systems: The spread of mechanisms tempering proportional representation across Europe
Authors: Bol Damien , Pilet Jean‐Benoit , Riera Pedro
Published: March 2015

There is an assumption in much of the electoral engineering literature that domestic episodes of electoral system choice occur in a vacuum, isolated from international influences. Yet this assumption remains largely untested, despite the comparative focus of much of that literature. This article focuses on part of this gap by considering two electoral mechanisms that seek to limit party system fragmentation under proportional representation – low district magnitudes and high electoral thresholds – and shows that the mechanisms have spread across many European countries during the post‐1945 period. Analyses reveal that national legislators are more likely to adopt one of these electoral mechanisms when a large number of peer countries have made similar choices within the last two or three years. This effect is robust to various model specifications and to the inclusion of multiple controls. The article also offers some qualitative evidence from case studies and parliamentary debates.
Prompted to treatment by the criminal justice system: Relationships with treatment retention and outcome among cocaine users
Authors: Kiluk Brian D. , Serafini Kelly , Malin‐Mayor Bo , Babuscio Theresa A. , Nich Charla , Carroll Kathleen M.
Published: March 2015

Background and Objectives

A substantial portion of individuals entering treatment for substance use have been referred by the criminal justice system, yet there are conflicting reports regarding treatment engagement and outcome differences compared to those not referred. This study examined baseline characteristic and treatment outcome differences among cocaine‐dependent individuals participating in cocaine treatment randomized trials.

Methods

This secondary analysis pooled samples across five completed randomized controlled trials, resulting in 434 participants. Of these, 67 (15%) were prompted to treatment by the criminal justice system.

Results

This subsample of criminal justice prompted (CJP) individuals did not differ from those not prompted by the criminal justice system in terms of gender, race/ethnicity, marital status, or age. However, the CJP group reported more years of regular cocaine use, more severe employment and legal problems, as well as less readiness to change prior to treatment. Treatment outcomes did not differ significantly from those without a criminal justice prompt, and on some measures the outcomes for CJP group were better (e.g., percentage of days cocaine abstinent, number of therapy sessions attended).

Discussion and Conclusions

These findings suggest that being prompted to treatment by the criminal justice system may not lead to poorer treatment engagement or substance use outcomes for individuals participating in randomized controlled treatment trials.

Scientific Significance

Despite some baseline indicators of poorer treatment prognosis, individuals who have been prompted to treatment by the criminal justice system have similar treatment outcomes as those presenting to treatment voluntarily. (Am J Addict 2015;24:225–232)