bluuebunny/crossref_metadata_2025 huggingface dataset:
In vitro toxicity evaluation of silica-coated iron oxide nanoparticles in human SHSY5Y neuronal cells
Authors: Kiliç Gözde , Costa Carla , Fernández-Bertólez Natalia , Pásaro Eduardo , Teixeira João Paulo , Laffon Blanca , Valdiglesias Vanessa
Published: October 2015

Iron oxide nanoparticles (ION) have been widely used in biomedical applications, for both diagnosis and therapy, due to their unique magnetic properties. They are intensively explored in neuromedicine mostly because of their ability to cross the blood brain barrier. Hence, their potential harmful effects on neuronal cells need to be carefully assessed. The objective of this study was to evaluate the toxicity of silica-coated ION (S-ION) (10–200 μg ml−1) on human neuronal SHSY5Y cells. Alterations in the cell cycle, cell death by apoptosis or necrosis, and membrane integrity were assessed as cytotoxicity parameters. Genotoxicity was determined by a γH2AX assay, a micronucleus (MN) test, and a comet assay. Complementarily, possible effects on DNA damage repair were also analysed by means of a DNA repair competence assay. All analyses were performed in complete and serum-free cell culture media. Iron ion release from the nanoparticles was notable only in complete medium. Despite being effectively internalized by the neuronal cells, S-ION presented in general low cytotoxicity; positive results were only obtained in some assays at the highest concentrations and/or the longest exposure time tested (24 h). Genotoxicity evaluations in serum-free medium were negative for all conditions assayed; in complete medium, dose and time-dependent increase in DNA damage not related to the production of double strand breaks or chromosome loss (according to the results of the γH2AX assay and MN test), was obtained. The presence of serum slightly influenced the behaviour of S-ION; further studies to investigate the formation of a protein corona and its role in nanoparticle toxicity are necessary.
Effect of base sequence context on the conformational heterogeneity of aristolactam-I adducted DNA: structural and energetic insights into sequence-dependent repair and mutagenicity
Authors: Kathuria Preetleen , Sharma Purshotam , Wetmore Stacey D.
Published: October 2015

Aristolochic acids (AAs) are nephrotoxic and potentially carcinogenic plant mutagens that form bulky DNA adducts at the exocyclic amino groups of the purines. The present work utilizes classical molecular dynamics simulations and free energy calculations to investigate the role of lesion site sequence context in dictating the conformational outcomes of DNA containing ALI-N6-dA, the most persistent and mutagenic adduct arising from the AAs. Our calculations reveal that the anti base-displaced intercalated conformer is the lowest energy conformer of damaged DNA in all sequence contexts considered (CXC, CXG, GXC and GXG). However, the experimentally-observed greater mutagenicity of the adduct in the CXG sequence context does not correlate with the relative thermodynamic stability of the adduct in different sequences. Instead, AL-N6-dA adducted DNA is least distorted in the CXG sequence context, which points toward a possible differential repair propensity of the lesion in different sequences. Nevertheless, the structural deviations between adducted DNA with different lesion site sequences are small, and therefore other factors (such as interactions between the adducted DNA and lesion-bypass polymerases during replication) are likely more important for dictating the observed sequence-dependent mutagenicity of ALI-N6-dA.
Converting the bis-FeIV state of the diheme enzyme MauG to Compound I decreases the reorganization energy for electron transfer
Authors: Dow Brian A. , Davidson Victor L.
Published: October 2015

The electron transfer (ET) properties of two types of high-valent hemes were studied within the same protein matrix; the bis-FeIV state of MauG and the Compound I state of Y294H MauG. The latter is formed as a consequence of mutation of the tyrosine which forms the distal axial ligand of the six-coordinate heme that allows it to stabilize FeIV in the absence of an external ligand. The rates of the ET reaction of each high-valent species with the type I copper protein, amicyanin, were determined at different temperatures and analysed by ET theory. The reaction with bis-FeIV wild-type (WT) MauG exhibited a reorganization energy (λ) that was 0.39 eV greater than that for the reaction of Compound I Y295H MauG. It is concluded that the delocalization of charge over the two hemes in the bis-FeIV state is responsible for the larger λ, relative to the Compound I state in which the FeV equivalent is isolated on one heme. Although the increase in λ decreases the rate of ET, the delocalization of charge decreases the ET distance to its natural substrate protein, thus increasing the ET rate. This describes how proteins can balance different ET properties of complex redox cofactors to optimize each system for its particular ET or catalytic reaction.
HFR code: a flexible replication scheme for cloud storage systems
Authors: Zhu Bing , Li Hui , Shum Kenneth W. , Li Shuo‐Yen Robert
Published: October 2015

Fractional repetition (FR) codes are a family of repair‐efficient storage codes that provide exact and uncoded node repair at the minimum bandwidth regenerating point. The advantageous repair properties are achieved by a tailor‐made two‐layer encoding scheme which concatenates an outer maximum‐distance‐separable (MDS) code and an inner repetition code. In this study, the authors generalise the application of FR codes and propose heterogeneous fractional repetition (HFR) code, which is adaptable to the scenario where the repetition degrees of coded packets are different. The authors provide explicit code constructions by utilising group divisible designs, which allow the design of HFR codes over a large range of parameters. The constructed codes achieve the system storage capacity under random access repair and have multiple repair alternatives for node failures. Further, the authors take advantage of the systematic feature of MDS codes and present a novel design framework of HFR codes, in which storage nodes can be wisely partitioned into clusters such that data reconstruction time can be reduced when contacting nodes in the same cluster.
Structural and vibrational properties of single crystals of Scandia, Sc2O3 under high pressure
Authors: Ovsyannikov Sergey V. , Bykova Elena , Bykov Maxim , Wenz Michelle D. , Pakhomova Anna S. , Glazyrin Konstantin , Liermann Hanns-Peter , Dubrovinsky Leonid
Published: October 2015

We report the results of single-crystal X-ray diffraction and Raman spectroscopy studies of scandium oxide, Sc2O3, at ambient temperature under high pressure up to 55 and 28 GPa, respectively. Both X-ray diffraction and Raman studies indicated a phase transition from the cubic bixbyite phase (so-called C-Res phase) to a monoclinic C2/m phase (so-called B-Res phase) at pressures around 25–28 GPa. The transition was accompanied by a significant volumetric drop by ∼6.7%. In addition, the Raman spectroscopy detected a minor crossover around 10–12 GPa, which manifested in the appearance of new and disappearance of some Raman modes, as well as in softening of one Raman mode. We found the bulk modulus values of the both C-Res and B-Res phases as B0 = 198.2(3) and 171.2(1) GPa (for fixed B′ = 4), respectively. Thus, the denser high-pressure lattice of Sc2O3 is much softer than the original lattice. We discuss possible mechanisms that might be responsible for the pronounced elastic softening in the monoclinic high-pressure phase in this “simple” oxide with an ultra-wide band gap.
Spin-wave-driven high-speed domain-wall motions in soft magnetic nanotubes
Authors: Yang Jaehak , Yoo Myoung-Woo , Kim Sang-Koog
Published: October 2015

We report on a micromagnetic simulation study of interactions between propagating spin waves and a head-to-head domain wall in geometrically confined magnetic nanotubes. We found that incident spin waves of specific frequencies can lead to sufficiently high-speed (on the order of a few hundreds of m/s or higher) domain-wall motions in the same direction as that of the incident spin-waves. The domain-wall motions and their speed vary remarkably with the frequency and the amplitude of the incident spin-waves. High-speed domain-wall motions originate from the transfer torque of spin waves' linear momentum to the domain wall, through the partial or complete reflection of the incident spin waves from the domain wall. This work provides a fundamental understanding of the interaction of the spin waves with a domain wall in the magnetic nanotubes as well as a route to all-magnetic control of domain-wall motions in the magnetic nanoelements.
Effects of atmospheric pressure cold plasma on human hepatocarcinoma cell and its 5-fluorouracil resistant cell line
Authors: Yang H. , Lu R. , Xian Y. , Gan L. , Lu X. , Yang X.
Published: October 2015

Atmospheric pressure cold plasma showed selective killing efficiency on cancer cells in vitro and in vivo, which makes plasma a potential option for cancer therapy. However, the plasma effects on chemotherapeutic drugs-resistant cells are rarely to be found. In this paper, the effects of plasma on human hepatocellular carcinoma Bel7402 cells and 5-fluorouracil (5-FU) resistant Bel7402/5FU cells were intensively investigated. The results showed that plasma induced superior toxicity to Bel7402 cells compared with Bel7402/5FU cells. Incubation with plasma-treated medium for 20 s induced more than 85% death rate in Bel7402 cells, while the same death ratio was achieved when Bel7402/5FU cells were treated for as long as 300 s. The hydrogen peroxide in the medium played a leading role in the cytotoxicity effects. Further studies implicated that when the treatment time was shorter than 60 s, the depolarization of mitochondrial membrane potential and apoptosis occurred through the intracellular reactive oxygen species accumulation in Bel7402 cells. Molecular analysis showed an increase in the transcription factor activity for AP-1, NF-кB, and p53 in Bel7402 cells. No obvious damage could be detected in plasma-treated Bel7402/5FU cells due to the strong intracellular reactive oxygen stress scavenger system.
Revisiting the glass transition and dynamics of supercooled benzene by calorimetric studies
Authors: Tu Wenkang , Chen Zeming , Li Xiangqian , Gao Yanqin , Liu Riping , Wang Li-Min
Published: October 2015

The glass transition and dynamics of benzene are studied in binary mixtures of benzene with five glass forming liquids, which can be divided into three groups: (a) o-terphenyl and m-xylene, (b) N-butyl methacrylate, and (c) N,N-dimethylpropionamide and N,N-diethylformamide to represent the weak, moderate, and strong interactions with benzene. The enthalpies of mixing, ΔHmix, for the benzene mixtures are measured to show positive or negative signs, with which the validity of the extrapolations of the glass transition temperature Tg to the benzene-rich regions is examined. The extrapolations for the Tg data in the mixtures are found to converge around the point of 142 K, producing Tg of pure benzene. The fragility m of benzene is also evaluated by extrapolating the results of the mixtures, and a fragility m ∼ 80 is yielded. The obtained Tg and m values for benzene allow for the construction of the activation plot in the deeply supercooled region. The poor glass formability of benzene is found to result from the high melting point, which in turn leads to low viscosity in the supercooled liquid.
Radio-frequency ion deflector for mass separation
Authors: Schlösser Magnus , Rudnev Vitaly , Ureña Ángel González
Published: October 2015

Electrostatic cylindrical deflectors act as energy analyzer for ion beams. In this article, we present that by imposing of a radio-frequency modulation on the deflecting electric field, the ion transmission becomes mass dependent. By the choice of the appropriate frequency, amplitude, and phase, the deflector can be used as mass filter. The basic concept of the new instrument as well as simple mathematic relations are described. These calculations and further numerical simulations show that a mass sensitivity is achievable. Furthermore, we demonstrate the proof-of-principle in experimental measurements, compare the results to those of from a 1 m linear time-of-flight spectrometer, and comment on the mass resolution of the method. Finally, some potential applications are indicated.
Investigation of gold/GaN nanorod arrays for hypersonic detection: The effect of periodicity
Authors: Yang Szu-Chi , Shen Tung-Po , Wu Tsung-Tsong , Huang Yu-Ru , Sun Chi-Kuang
Published: October 2015

Gold nanodisk arrays on the upper surface of GaN nanorods were developed with the aim of achieving hypersonic imaging with a detection frequency above 10 GHz. In this paper, we report the interesting phenomenon that the hypersonic signal detected by a single gold nanodisk in this structure might be dependent on the array periodicity and rod length. When the array periodicity is of the same order of or longer than the surface hypersonic wavelength, the detected signal would be enhanced by the period-dependent resonance of the surface hypersonic waves scattered by the nanorod/substrate interface. When the array periodicity is smaller than the surface hypersonic wavelength, the coupling of extensional modes between neighboring nanorods, as the detection frequency approaches the coupled-extensional-mode frequency, would enhance the detected signals. Although these enhancements are beneficial to heat transport at nanorod/substrate interfaces, they will cause cross-talk between the neighboring detection rod unit and should be avoided by choosing the correct period for imaging array applications. Our result further indicates that the extensional mode coupling could be avoided by increasing the rod-length to shift the extensional mode frequency away from the detection frequency. This work not only investigates the transport behavior of hypersonic-frequency acoustic phonons at the interface between a bulk material and a nanostructure, but also suggests that the effects of the periodicity and nanorod length need to be taken into consideration for the design of future hypersonic imaging arrays.
Magnetic and structural properties of ferromagnetic Fe5PB2 and Fe5SiB2 and effects of Co and Mn substitutions
Authors: McGuire Michael A. , Parker David S.
Published: October 2015

Crystallographic and magnetic properties of Fe5PB2, Fe4CoPB2, Fe4MnPB2, Fe5SiB2, Fe4CoSiB2, and Fe4MnSiB2 are reported. All adopt the tetragonal Cr5B3 structure-type and are ferromagnetic at room temperature with easy axis of magnetization along the c-axis. The spin reorientation in Fe5SiB2 is observed as an anomaly in the magnetization near 170 K and is suppressed by substitution of Co or Mn for Fe. The silicides are found to generally have larger magnetic moments than the phosphides, but the data suggest smaller magnetic anisotropy in the silicides. Cobalt substitution reduces the Curie temperatures by more than 100 K and ordered magnetic moments by 16%–20%, while manganese substitution has a much smaller effect. This suggests Mn moments align ferromagnetically with the Fe and that Co does not have an ordered moment in these structures. Anisotropic thermal expansion is observed in Fe5PB2 and Fe5SiB2, with negative thermal expansion seen along the c-axis of Fe5SiB2. First principles calculations of the magnetic properties of Fe5SiB2 and Fe4MnSiB2 are reported. The results, including the magnetic moment and anisotropy, are in good agreement with experiment.
Spin wave scattering and interference in ferromagnetic cross
Authors: Nanayakkara Kasuni , Jacob Ajey P. , Kozhanov Alexander
Published: October 2015

Magnetostatic spin wave scattering and interference across a CoTaZr ferromagnetic spin wave waveguide cross junction were investigated experimentally and by micromagnetic simulations. It is observed that the phase of the scattered waves is dependent on the wavelength, geometry of the junction, and scattering direction. It is found that destructive and constructive interference of the spin waves generates switching characteristics modulated by the input phase of the spin waves. Micromagnetic simulations are used to analyze experimental data and simulate the spin wave scattering and interference.
Vertical cavity lasing from melt-grown crystals of cyano-substituted thiophene/phenylene co-oligomer
Authors: Tanaka Yosuke , Goto Kaname , Yamashita Kenichi , Yamao Takeshi , Hotta Shu , Sasaki Fumio , Yanagi Hisao
Published: October 2015

Vertical-cavity organic lasers are fabricated with melt-grown crystals of a cyano-substituted thiophene-phenylene co-oligomer. Due to lying molecular orientation, surface-emitting lasing is achieved even in the half-cavity crystal grown on a distributed Bragg reflector (DBR) under optical pumping at room temperature. Anticrossing splits in angle-resolved photoluminescence spectra suggest the formation of exciton-polaritons between the cavity photons and the confined Frenkel excitons. By constructing the full-cavity structure sandwiched between the top and bottom DBRs, the lasing threshold is reduced to one order, which is as low as that of the half cavity. Around the threshold, the time profile of the full-cavity emission is collapsed to a pulsed shape accompanied by a finite turn-on delay. We discuss these observed characteristics in terms of a polariton contribution to the conventional photon lasing.
Supplementation with crushed rapeseed causes reduction of methane emissions from lactating dairy cows on pasture
Authors: Storlien T. M. , Prestløkken E. , Beauchemin K. A. , McAllister T. A. , Iwaasa A. , Harstad O. M.
Published: October 2015

The main objective of this study was to investigate the effect of supplementing a pasture diet with crushed rapeseed on enteric methane (CH4) emissions from lactating dairy cows. The experiment was conducted as a crossover design using eight multiparous lactating Norwegian red dairy cows [(means ± s.d.) 548 ± 52 kg bodyweight, 38 ± 14 days in milk and 35 ± 3.7 kg milk/day, at the start of the experiment] maintained in two groups and fed two diets in two periods with the second period extended (18 days) to investigate the persistence of the CH4 response. Four of the eight cows were fitted with a rumen cannula with two cannulated cows assigned to each group. Cows were maintained on pasture (24 h/day) with access to 9 kg/day of concentrate containing 10% crushed rapeseed (RSC) or a control concentrate (CC). Dietary fat content was 63 g/kg dry matter for RSC and 42 g/kg dry matter for CC. The CH4 production was measured for five consecutive days in each period using the sulfur hexafluoride tracer gas technique. Compared with CC, RSC caused a reduction in enteric CH4 emission (221 vs 251 g/day and 8.1 vs 9.0 g/kg of energy-corrected milk), and this response persisted in the extension period. Cows fed RSC had higher milk yield compared with cows fed CC (31.7 vs 29.6 kg/day). However, milk fat and protein content were lower in milk from cows fed RSC than CC. Therefore, energy-corrected milk was not affected by treatment. Feeding RSC lowered milk fat content of palmitic acid compared with CC. The study showed that adding crushed RSC to the diet can be an effective means of reducing CH4 emissions from lactating dairy cows on pasture, without negatively affecting milk production.
La tolerancia a la ambigüedad y los procesos cognitivos del traductor
Authors: Bolaños-Medina Alicia
Published: October 2015

Tolerance for ambiguity (TA) is a cognitive factor that influences the perception of uncertainty and that, when not sufficiently present, may adversely affect problem solving and decision making, both key processes in translation. This being so, it has even been stated that TA is a personality trait which must be taken into account as far as translator training and recruitment are concerned (Tirkkonen-Condit 2000). After reviewing the main research conducted so far on TA from the disciplines of psychology and translation, the results of an exploratory field study based on descriptive methodology and self-report measures are shown. The Multiple Stimulus Types Ambiguity Tolerance Scale (Arquero and McLain 2010) or MSTAT-II is the main psychometric instrument applied to all participants (n=107). On the one hand, a positive correlation was found between tolerance of ambiguity and individuals’ own assessment of their self-efficacy when searching the Internet for documentation. On the other hand, those subjects who thought that they did not meet the requirements for becoming professional translators in the future obtained low scores in TA, and a significant difference in TA was found between them and those who believed to meet such requirements. The results of this preliminary work suggest that TA is relevant to the study of the cognitive processes of translators and that psychometric instruments of proven reliability and validity can be useful for process-oriented translation research.
Big business of plagiarism under the guise of (re)translation
Authors: Şahin Mehmet , Duman Derya , Gürses Sabri
Published: October 2015

Taking Turkey’s case as a basis, the current study focuses on the retranslation practice with an aim to discuss plagiaristic forms of retranslation which may create serious repercussions in the field of translation such as violating translators’ copyrights, complicating the issue of translator’s voice, producing defective cultural artifacts and affecting culture in general negatively. The study tries to outline and exemplify commonly-accepted impetuses for retranslation and inquire the validity of the rationale for the retranslations with a particular focus on Turkey. For our analysis, we used a total of 40 classical books distributed by a national newspaper as a promotional campaign. Following a brief discussion on voice in translation, an overview of publishing and retranslation practices in Turkey; this study presents guidelines for a more comprehensive analysis of the phenomenon of plagiarism in retranslation and translation in general. The analyses of both qualitative and quantitative data derived from the sample of classical books showed that the books were just reproduction rather than retranslation or translation at all. The article concludes with a discussion on the possible impact of fake retranslations on translation practice and culture in general and calls for further empirical studies to prevent plagiarism in translation.
From the shop floor to the kitchen table: the shifting centre of precarious workers’ politics in South Africa
Authors: Scully Ben
Published: October 2015

This article argues that, as wage work has become more precarious, the importance of the household in the livelihood strategies of precarious South African workers has increased. The shifting importance of the household in relation to the workplace in the economic lives of workers has implications for the political strategies that these workers adopt. The article draws on data from a national household survey combined with insights from the author's fieldwork across rural and urban sites in South Africa. It contributes to the growing literature on the politics of precarious work in the global South.
Preparation of reminiscent aroma mixture of Japanese soy sauce
Authors: Bonkohara Kaori , Fuji Maiko , Nakao Akito , Igura Noriyuki , Shimoda Mitsuya
Published: October 2015

To prepare an aroma mixture of Japanese soy sauce by fewest components, the aroma concentrate of good sensory attributes was prepared by polyethylene membrane extraction, which could extract only the volatiles with diethyl ether. GC-MS-Olfactometry was done with the aroma concentrate, and 28 odor-active compounds were detected. Application of aroma extract dilution analysis to the separated fraction revealed high flavor dilution factors with respect to acetic acid, 4-hydroxy-2(or5)-ethyl-5(or2)-methyl-3(2H)-furanone (HEMF), 3-methyl-1-butanol (isoamyl alcohol), and 3-(methylsulfanyl)propanal (methional). A model aroma mixture containing above four odorants showed a good similarity with the aroma of the soy sauce itself. Consequently, the reminiscent aroma mixture of soy sauce was prepared in water. The ratio of acetic acid, HEMF, isoamyl alcohol, and methional was 2500:300:100:1.
Left Main Coronary Artery Compression in Pulmonary Arterial Hypertension
Authors: Albadri Kadhem , Jensen Jesper M. , Christiansen Evald H. , Mellemkjær Søren , Nielsen‐Kudsk Jens Erik
Published: October 2015

In patients with pulmonary arterial hypertension (PAH), chest pain is most likely due to right ventricular demand ischemia. We report a patient with idiopathic PAH who developed severe angina due to extrinsic compression of the left main coronary artery (LMCA) from a dilated pulmonary artery trunk. The diagnosis was verified by electrocardiogram after exercise, coronary angiography including intravascular ultrasound, and cardiac multidetector computed tomography (MDCT). The origin of the LMCA was high in the left coronary sinus, facilitating extrinsic compression. The patient was successfully treated by percutaneous coronary intervention with stent implantation in the LMCA. Extrinsic compression of the LMCA is a severe and potentially fatal complication that should be considered in all patients with PAH and angina. MDCT is the method of choice for first‐line diagnosis.
Unilateral Emphysema in Infancy, a Rare Presentation of Aberrant Bronchial Artery
Authors: El-Desoky Tarek , Osman Engy , Osman Amal , Elgamal Adel M. , Zaki Ahmed
Published: October 2015

Aberrant bronchial arteries are rarely seen and may originate from various vascular structures. Hemoptysis is the most common clinical presentation of cases with anomalous bronchial artery. We report a case of a 1-month-old infant presented with respiratory distress and left lung emphysema. Radiologic investigations and bronchoscopy revealed that the cause is an aberrant left bronchial artery compressing the left main bronchus. Surgical division of the aberrant vessel was performed with gradual improvement of the emphysema and respiratory distress. Unilateral emphysema due to vascular compression was previously reported. However, to the best of our knowledge, this is the first reported case of aberrant bronchial artery presenting with external compression of a main bronchus and unilateral emphysema. Also, this is the youngest reported case with an aberrant bronchial artery.
Tuning microscale, retractable, membrane-breaking protein needles
Authors: Polka Jessica K , Silver Pamela A
Published: October 2015

The refractile (R) bodies found in Caedibacter taeniospiralis, a bacterial endosymbiont of Paramecium tetraurelia, are large, polymeric protein structures that can switch between two conformations. At cytoplasmic pH, they resemble coiled ribbons of protein 500nm in diameter. At low pH, they extend to form hollow needles up to 20 microns long. They can be expressed heterologously from an operon containing four short open reading frames and can function in vitro in diverse buffer conditions. In this study, R bodies purified from Escherichia coli were found to be capable of undergoing many consecutive extension-contraction cycles. Furthermore, the solubility of R bodies, which can easily be interpreted by eye, was found to correlate with their extension state. This macroscopic phenotype was used to develop a quantitative, high-throughput assay for R body state, enabling a visual screen of R body mutants defective in extension. The role of specific amino acids in extension was determined, and this information was used to construct rationally-designed mutants tailored to extend at higher pH. Furthermore, R bodies were able to rupture E. coli spheroplasts to release soluble proteins across lipid bilayers. Taken together, these results show that R bodies act as tunable, pH-actuated pistons suitable for a variety of membrane-breaking applications.
Combining Dependent P-values with an Empirical Adaptation of Brown’s Method
Authors: Poole William , Gibbs David L. , Shmulevich Ilya , Bernard Brady , Knijnenburg Theo
Published: October 2015

Motivation:Combining P-values from multiple statistical tests is a common exercise in bioinformatics. However, this procedure is non-trivial for dependent P-values. Here we discuss an empirical adaptation of Brown’s Method (an extension of Fisher’s Method) for combining dependent P-values which is appropriate for the correlated data sets found in high-throughput biological experiments.

Results:We show that Fisher’s Method is biased when used on dependent sets of P-values with both simulated data and gene expression data from The Cancer Genome Atlas (TCGA). When applied on the same data sets, the Empirical Brown’s Method provides a better null distribution and a more conservative result.

Availability:The Empirical Brown’s Method is available in Python, R, and MATLAB and can be obtained fromhttps://github.com/IlyaLab/CombiningDependentPvaluesUsingEBM.1
Y-chromosome structural diversity in the bonobo and chimpanzee lineages
Authors: Oetjens Matthew T. , Shen Feichen , Emery Sarah B. , Zou Zhengting , Kidd Jeffrey M.
Published: October 2015

The male specific regions of primate Y-chromosomes (MSY) are enriched for multi-copy genes highly expressed in the testis. These genes are located in large repetitive sequences arranged as palindromes, inverted-, and tandem-repeats termed amplicons. In humans, these genes have critical roles in male fertility and are essential for the production of sperm. The structure of human and chimpanzee amplicon sequences show remarkable difference relative to the remainder of the genome, a difference that may be the result of intense selective pressure on male fertility. Four populations of common chimpanzees have undergone extended periods of isolation and appear to be in the early process of speciation. A recent study found amplicons enriched for testis-expressed genes on the primate X-chromosome the target of hard selective sweeps, and male-fertility genes on the Y-chromosome may also be the targets of selection. However, little is understood about Y-chromosome amplicon diversity within and across chimpanzee populations. Here, we analyze 9 common chimpanzee (representing three subspecies:Pan troglodytes schweinfurthii, Pan troglodytes ellioti, andPan troglodytes verus) and two bonobo (Pan paniscus) male whole-genome sequences to assess Y ampliconic copy-number diversity across the Pan genus. We observe that the copy-number of Y chromosome amplicons is variable amongst chimpanzees and bonobos, and identify several lineage-specific patterns, including variable copy-number of azoospermia candidatesRBMYandDAZ. We detect recurrent switchpoints of copy-number change along the ampliconic tracts across chimpanzee populations, which may be the result of localized genome instability or selective forces.
Policies to promote entrepreneurial activity and economic performance
Authors: Castaño-Martínez María-Soledad , Méndez-Picazo María-Teresa , Galindo-Martín Miguel-Ángel
Published: October 2015

Purpose

– The purpose of this paper is to analyse the effects of some political measures on entrepreneurship to promote economic growth and employment, specifically, R
&
D policies, training, elimination of administrative barriers, access to finance support and promotion of entrepreneurial culture.

Design/methodology/approach

– Seven hypotheses are tested developing a latent variables model with data from 13 European countries (Austria, Belgium, Denmark, Finland, France, Germany, Ireland, Italy, the Netherlands, Portugal, Spain, Sweden and UK) in 2012, using partial least squares estimation method.

Findings

– Greater expenditure on R
&
D by governments and universities, public investment in education and measures to stimulate entrepreneurial culture have a positive effect on entrepreneurship. Furthermore, countries with complex legal systems which regulate the start-up of an economic activity and where access to credit is complicated, present lower levels of entrepreneurship. Societies with a greater number of innovative entrepreneurs present higher levels of entrepreneurial activity and economic performance. Finally, human capital and entrepreneurial activity positively affect economic performance in the case of the European countries studied in the sample.

Practical implications

– The results obtained in the paper would facilitate the design of measures to stimulate to entrepreneurs and improve economic performance.

Originality/value

– Several factors, qualitative and quantitative, have been considered in the analysis that they have not traditionally included in the analysis of the entrepreneurship behaviour taking into account the role played by the policy makers measures to improve such behaviour.
20 years of performance measurement in sustainable supply chain management – what has been achieved?
Authors: Beske-Janssen Philip , Johnson Matthew Phillip , Schaltegger Stefan
Published: October 2015

Purpose

– The purpose of this paper is to systematically review the academic literature on sustainability performance measurement for sustainable supply chain management (SSCM) published over the past 20 years. The development and current state of instruments, concepts and systems to measure and manage sustainability performance are examined and research gaps are identified.

Design/methodology/approach

– A systematic literature review is conducted spanning two decades of publications in peer-reviewed academic journals. The publications are analyzed with regard to frequency and bibliometrical metrics and research content.

Findings

– The research examines the development of the field over 20 years, which has witnessed a steep rise in related publications only for the past five years, indicating a late interest in the area compared to other sustainability topics. Social performance measures entered the discussion particularly late, whereas economic and environmental measurement almost exclusively dominated the field for the first few years.

Research limitations/implications

– The authors identify research gaps and discuss future directions for research. The analysis shows how the research area develops from a topic dealt with by a small group of interested researchers into a broader research field acknowledged in the scientific community.

Practical implications

– Findings underline the importance of measuring performance for sustainability management of supply chains. The review identifies what measurement and management tools are discussed in the literature over time.

Originality/value

– This is the first literature review on sustainability performance measurement for SSCM summarizing the development over the time span of 20 years.
Horizontal logistics collaboration for enhanced supply chain performance: an international retail perspective
Authors: Sanchez Rodrigues Vasco , Harris Irina , Mason Robert
Published: October 2015

Purpose

– The paper aims to develop a supply chain-driven model horizontal logistics collaboration (HLC). HLC initiatives can fail. To improve the chance of success, a thorough consideration of the potential issues involved, such as seeking supply chain partners’ support, ensuring access to information/data security and assessing whether an HLC model could bring improvements to a wide range of supply chain metrics rather than reductions in distribution costs only, needs to be understood before deciding to proceed with such an initiative.

Design/methodology/approach

– A two-stage methodology is deployed. As part of Stage 1, a series of 20 semi-structured interviews with senior managers from retailers, retailers’ suppliers and logistics service providers were undertaken. Subsequently, in Stage 2, a focus group with practitioners from retailers and logistics service providers was run to verify the findings gathered during Stage 1. Four elements of a new HLC project being considered are investigated by supply chain champions across the UK Fast-Moving Costumer Goods industry, namely, consideration factors, required synergies, enablers and anticipated output metrics.

Findings

– When considering whether to embark on an HLC project, the supply chain requirements need to be taken into account and potential supply chain performance benefits projected. The paper identified several consideration factors; synergies and enablers that support the development of HLC projects are identified, such as legislation, trust among partners, common suppliers and delivery bases, capable third party logistics (3PL) and an effective commercial model, including a fair sharing of benefits.

Research limitations/implications

– The research provides new understanding in accounting for the needs of the supply chain when considering an HLC initiative involving leading players from the retail sector.

Practical implications

– The importance of taking a supply chain approach when evaluating the feasibility of HLC is demonstrated. HLC arrangements among competing supply chains need to be designed and run by taking account of all supply chain partners, namely, suppliers, 3PLs and customers (in this case, retailers).

Originality/value

– The contribution is threefold: identification of outset consideration factors, ideal required synergies, actioning enablers and wider supply chain metrics of HLC; development of a supply chain-driven model for HLC, which includes in the decision-making whether or not to adopt a horizontal logistics collaboration model, wide supply chain metrics such as stock levels of finished products and shelf availability, inventory, working and fixed capital, and product waste in addition to distribution costs; and, the proposal of a new definition for HLC which challenges published definitions.
Do arbuscular mycorrhizal fungi stabilize litter‐derived carbon in soil?
Authors: Verbruggen Erik , Jansa Jan , Hammer Edith C. , Rillig Matthias C.
Published: October 2015

Fine roots and mycorrhiza often represent the largest input of carbon (C) into soils and are therefore of primary relevance to the soil C balance. Arbuscular mycorrhizal (AM) fungi have previously been found to increase litter decomposition which may lead to reduced soil C stocks, but these studies have focused on immediate decomposition of relatively high amounts of high‐quality litter and may therefore not hold in many ecological settings over longer terms.

Here, we assessed the effect of mycorrhizal fungi on the fate of C and nitrogen (N) contained within a realistic amount of highly 13C‐/15N‐labelled root litter in soil. This litter was either added fresh or after a 3‐month incubation period under field conditions to a hyphal in‐growth core where mycorrhizal abundance was either reduced or not through rotation. After 3 months of incubation with a plant under glasshouse conditions, the effect of turning cores on residual 13C and 15N inside the cores was measured, as well as 13C incorporation in microbial signature fatty acids and 15N incorporation of plants.

Turning of cores increased the abundance of fungal decomposers and 13C loss from cores, while 15N content of cores and plants was unaffected. Despite the difference in disturbance that turning the cores could have caused, the results suggest that mycorrhizal fungi and field incubation of litter acted to additively increase the proportion of 13C left in cores.

Synthesis. Apart from stimulating litter decomposition as previously shown, mycorrhizas can also stabilize C during litter decomposition and this effect is persistent through time.
Alternative Estimator for Industrial Gender Wage Gaps: A Normalized Regression Approach
Authors: Yun Myeong‐Su , Lin Eric S.
Published: October 2015

Using normalized regression equations, we propose an alternative estimator of industrial gender wage gaps which is identified in the sense that it is invariant to the choice of an unobserved non‐discriminatory wage structure, and to the choice of the reference groups of any categorical variables. The proposed estimator measures the pure impact of industry on gender wage gaps after netting out wage differentials due to differences in characteristics and their coefficients between men and women. Furthermore, the proposed estimator is easy to implement, and hypothesis testing is straightforward. We compare the proposed estimator with existing estimators using samples from the 1998 US Current Population Survey.
The Cyclical Properties of Unemployment and Vacancies in Taiwan
Authors: Kashiwagi Masanori
Published: October 2015

This paper examines the quantitative performance of the standard search and matching model in explaining the cyclical behaviour of Taiwan's labour market. Although the model accounts well for the data in some dimensions, simulated volatility is counterfactually very low, as pointed out in Shimer (2005) for the US labour market. Nevertheless, calibrated to Taiwan's data, the model explains a higher proportion of the observed volatility than the Shimer (2005) results, due to a higher parameter value for leisure; if an extremely high value is assumed, the model explains substantially better, but still partially, the volatility in Taiwan.
Possible Best Currency Basket Selection from the Perspective of Real Effective Exchange Rate
Authors: Wang Aihua , Balli Faruk , Li Xiumin
Published: October 2015

We calculated the real effective exchange rate indexes and measured their volatilities based on four currency baskets to find which currency basket is optimal for achieving China's policy target of keeping exchange rates stable. The volatility of the bilateral exchange rate between the RMB and the US dollar is also calculated to make a comparative analysis. Results showed that the bilateral exchange rate of the RMB and the US dollar is only stable in special time periods. In most time periods, pegging to the G3 currency basket is optimal to achieve the goal of stabilizing exchange rates while pegging to the AMU currency basket will result in the most volatile exchange rates.
The South Arabian form and its implications for the interpretation of desert kites
Authors: Brunner Ueli
Published: October 2015

There is a distinctive type of desert kite in southern Arabia. On low‐resolution aerial photographs it has the form of a Y and a closer look reveals a scissor‐shaped structure. The head and the tails are very distinctive: the head is an open structure with a continuous wall on the right side and many chambers on the left; the tail consists of many piles of stones arranged in a straight line, and only towards the head does it change into a continuous wall. These impressions, together with the—now known—wide distribution of desert kites in non‐arid regions as well, lead to the idea that the stone alignments of Carnac in France could also have served as animal traps.
Hunting in pre‐Islamic Arabia in light of the epigraphic evidence
Authors: Maraqten Mohammed
Published: October 2015

The hunting of wild animals for food, sport or for the defence of people and herds, was common in the ancient Near East, especially in early times. This paper gives a survey of hunting practices in pre‐Islamic Arabia primarily from the beginning of the first millenniumBCEto the eve of Islam in light of the epigraphic evidence and of rock art as well as archaeological discoveries.
Satisfaction of undergraduate students at University of Jordan after root canal treatment of posterior teeth using rotary or hand preparation
Authors: Abu‐Tahun Ibrahim , El‐Ma'aita Ahmad , Khraisat Ameen
Published: October 2015

The aim of this study was to report the satisfaction of fifth year undergraduate students on the clinical use of rotary endodontic preparation compared with stainless steel standard technique and to evaluate the impact of rotary nickel–titanium instruments on undergraduate teaching. This study was carried out by the fifth year undergraduate students attending peer review sessions as a part of their training program using a questionnaire to assess their satisfaction with these two techniques. The overall results indicated a statistically significant satisfaction of the undergraduate students with the use of the nickel–titanium system (P < 0.001) compared to stainless steel standard technique. Under the conditions of this study, the results showed a positive acceptance and consensus among novice dental students regarding the use of ProTaper rotary files and the need for undergraduate teaching of rotary nickel–titanium systems in Jordan.
A Unified Set-Based Test with Adaptive Filtering for Gene–Environment Interaction Analyses
Authors: Liu Qianying , Chen Lin S. , Nicolae Dan L. , Pierce Brandon L.
Published: October 2015

In genome-wide gene–environment interaction (GxE) studies, a common strategy to improve power is to first conduct a filtering test and retain only the SNPs that pass the filtering in the subsequent GxE analyses. Inspired by two-stage tests and gene-based tests in GxE analysis, we consider the general problem of jointly testing a set of parameters when only a few are truly from the alternative hypothesis and when filtering information is available. We propose a unified set-based test that simultaneously considers filtering on individual parameters and testing on the set. We derive the exact distribution and approximate the power function of the proposed unified statistic in simplified settings, and use them to adaptively calculate the optimal filtering threshold for each set. In the context of gene-based GxE analysis, we show that although the empirical power function may be affected by many factors, the optimal filtering threshold corresponding to the peak of the power curve primarily depends on the size of the gene. We further propose a resampling algorithm to calculate P-values for each gene given the estimated optimal filtering threshold. The performance of the method is evaluated in simulation studies and illustrated via a genome-wide gene–gender interaction analysis using pancreatic cancer genome-wide association data.
Prepregnancy Obesity and Primary Cesareans among Otherwise Low‐Risk Mothers in 38 U.S. States in 2012
Authors: Declercq Eugene , MacDorman Marian , Osterman Michelle , Belanoff Candice , Iverson Ronald
Published: October 2015

Background

The United States has recently experienced increases in both its rate of obesity and its cesarean rate. Our objective was to use a new item measuring prepregnancy body mass index (BMI) on the U.S. Standard Certificate of Live Birth to examine at a population level the relationship between maternal obesity and primary cesarean delivery for women at otherwise low risk for cesarean delivery.

Methods

By 2012, 38 states with 86 percent of United States births had adopted the U.S. Standard Certificate. The sample was limited to the 2,233,144 women who had a singleton, vertex, term (37–41 weeks) birth in 2012 and no prior cesarean. We modeled the likelihood of a primary cesarean by BMI category, controlling for maternal socio‐demographic and medical characteristics.

Results

Overall, 46.4 percent of otherwise low‐risk mothers had a prepregnancy BMI in the overweight (25.1%) or obese (21.3%) categories, with the obese category distributed as follows: obese I (BMI 30.0–34.9, 12.4%); obese II (BMI 35.0–39.9, 5.5%); and obese III (BMI 40+, 3.5%). Obesity rates were highest among American Indian and Alaska Native (32.5%) and non‐Hispanic black mothers (30.5%). After adjustment for demographic and medical risks, the adjusted risk ratios (95% confidence intervals) of cesarean for low‐risk primiparas were: 1.61 (1.60–1.63) for obese I, 1.86 (1.83–1.88) for obese II, and 2.21 (2.18–2.25) for obese III mothers compared with mothers in the normal weight category.

Discussion

A relationship between prepregnancy obesity and primary cesarean delivery among relatively low‐risk mothers remained even after controlling for social and medical risk factors.