bluuebunny/crossref_metadata_2025 huggingface dataset:
High‐efficiency single etch step apodized surface grating coupler using subwavelength structure
Authors: Benedikovic Daniel , Cheben Pavel , Schmid Jens H. , Xu Dan‐Xia , Lapointe Jean , Wang Shurui , Halir Robert , Ortega‐Moñux Alejandro , Janz Siegfried , Dado Milan
Published: October 2014

Grating couplers are key elements enabling the coupling of light between planar waveguide circuits and optical fibers. In this work, it is demonstrated using simulations and experiments that a high coupling efficiency can be achieved for an arbitrary buried oxide thickness by judicious adjustment of the grating radiation angle. The coupler strength is engineered by subwavelength structure, allowing straightforward apodization and single etch step fabrication. The design has been implemented using Fourier‐eigenmode expansion and finite difference time domain methods. The measured coupling loss of a continuously apodized grating is −2.16 dB with a 3 dB bandwidth of 64 nm, therefore opening promising prospects for low‐cost and high‐volume fabrication using 193 nm deep‐ultraviolet lithography. It is also shown by simulations that a coupling loss as low as −0.42 dB is predicted for a modified coupler structure with bottom mirror.
Performance of modified‐release tacrolimus after conversion in liver transplant patients indicates potentially favorable outcomes in selected cohorts
Authors: Considine Aisling , Tredger J. Michael , Heneghan Michael , Agarwal Kosh , Samyn Marianne , Heaton Nigel D. , O'Grady John G. , Aluvihare Varuna R.
Published: October 2014

Clinical outcomes, dose changes, and dose‐equalized tacrolimus concentrations were examined sequentially in 129 liver transplantation (LT) recipients after successful conversion to once daily modified‐release tacrolimus either early (within 1 month) or late (>1 month) after LT. The data were compared with data for a group of 60 patients maintained on twice daily conventional‐release tacrolimus. Formulation‐ and time‐dependent changes in dose requirements for once and twice daily tacrolimus differed after transplantation. A 1.7‐fold initial increase in the median daily dose was required to achieve target tacrolimus concentrations in the early‐conversion cohort (P = 0.006), whereas a 1.25‐fold increase was required for those converted later (P = 0.013 and P < 0.001 for the difference). In the subsequent 2 months, the median daily dose fell by 20% in the early‐conversion cohort, remained stable for the late‐conversion cohort, but rose by 33% with conventional therapy. Lower median dose‐equalized concentrations persisted for up to 3 months after the conversion to modified‐release therapy. Sex, ethnicity, and the underlying liver disease did not significantly affect these variables. The frequency of treated biopsy‐proven acute rejection episodes fell approximately 4‐fold after the conversion to modified‐release tacrolimus, most notably in the late‐conversion cohort, which experienced a high incidence of rejection before conversion. Posttransplant increases in serum creatinine concentrations were smaller after the introduction of modified‐release tacrolimus in the late‐conversion group (0.7 versus 4 mg/mL for twice daily tacrolimus over 6 months). Reduced interpatient variability in tacrolimus concentrations was evident in the early‐conversion cohort versus the twice daily cohort. A decline in intrapatient variability accompanied the reduction in acute rejection in the late‐conversion cohort. Our data highlight potential benefits for the rejection rate and renal function on conversion to once daily modified‐release tacrolimus late after LT. Liver Transpl 21:29‐37, 2015. © 2014 AASLD.
Characterization of Langmuir Films Prepared from Copolyesterurethanes Based on Oligo(ω‐pentadecalactone) and Oligo(ε‐caprolactone) Segments
Authors: Schöne Anne‐Christin , Schulz Burkhard , Richau Klaus , Kratz Karl , Lendlein Andreas
Published: October 2014

A series of multiblock copolymers (PDLCL) synthesized from oligo(ω‐pentadecalactone)diol (OPDL) and oligo(ε‐caprolactone)diol (OCL), which are linked by 2,2(4),4‐trimethyl‐hexa­methylene diisocyanate (TMDI), is investigated by the Langmuir monolayer technique at the air–water interface. Brewster angle microscopy (BAM) and spectroscopic ellipsometry are employed to characterize the polymer film morphologies in situ. PDLCL containing ≥40 wt% OCL segments form homogeneous Langmuir monofilms after spreading. The film elasticity modulus decreases with increasing amounts of OPDL segments in the copolymer. In contrast, the OCL‐free polyesterurethane OPDL‐TMDI cannot be spread to monomolecular films on the water surface properly, and movable slabs are observed by BAM even at low surface pressures. The results of the in situ morphological characterization clearly show that essential information concerning the reliability of Langmuir monolayer degradation (LMD) experiments cannot be obtained from the evaluation of the π–A isotherms only. Consequently, in situ morphological characterization turns out to be indispensable for characterization of Langmuir layers before LMD experiments.

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On the semilinear Schrödinger equation with time dependent coefficients
Authors: Gonda Takuya , Machihara Shuji , Ozawa Tohru
Published: October 2014

We consider nonlinear Schrödinger equation with time dependent coefficients. Fanelli [5] found a transformation between solutions of the original equation and of the usual Schrödinger equation with power nonlinearity involving time dependent coefficients in some Lorentz spaces. In this paper we extend the results in [5] in space‐time integrability properties of solutions. Particularly, we prove that the existence and uniqueness of solutions can be described exclusively in terms of Lebesgue spaces (not Lorentz spaces as in [5]) as far as the space integrability of solutions. We also discuss the equation with coefficient of an explicit homogeneous function and describe the associated Strichartz estimate and contraction mapping argument.
Kinetics of Magnetic Field‐Induced Orientational Ordering in Block Copolymer/Superparamagnetic Nanoparticle Composites
Authors: Raman Vinay , Hatton T. Alan , Olsen Bradley D.
Published: October 2014

The combination of external potential dynamics and Brownian dynamics is introduced to study the kinetics of orientational ordering in block copolymer/superparamagnetic nanoparticle composites where the particles are smaller than the domain spacing and preferentially segregate into one block of the copolymer. This simulation method accounts for both excluded volume interactions and dipolar interactions between particles to quantify alignment kinetics. Two‐dimensional simulations reveal that higher dipolar interaction strengths lead to faster alignment of the block copolymer, where the orientation kinetics obeys an exponential rate law. The observed rate of alignment increases with increasing dipolar interaction strength and is dependent on the initial state of the block copolymer. The primary mechanism of orientational ordering is found to be the redistribution of monomer segments leading to bridging and growth of the block copolymer domains around the nanoparticles.

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Growth of White Rot Fungi in Composites Produced from Urban Plastic Waste and Wood
Authors: Catto André Luis , Rosseto Eduardo Soares , Reck Mateus Arduvino , Rossini Katiandry , da Silveira Rosa Mara Borges , Santana Ruth Marlene Campomanes
Published: October 2014

In the search for new biodegradable materials is found the combination of natural fibers with conventional polymeric materials or biodegradable polymers. The incorporation of natural fibers to thermoplastic polymer matrix is associated with improvement of their properties due to advantages such as the fact that the natural fibers are biodegradable and less abrasive when compared to synthetic fibers. The materials produced with conventional synthetic polymers are considered inert to immediate attack of microorganisms, as thermoplastic polymers used in this research, PP (polypropylene) and EVA (ethylene vinyl acetate). Thus, this study aims to evaluate the potential for biodegradation of wood plastic composites (WPC) obtained through the use of post‐consumer bottle caps and wood flour. The monitoring was conducted through cultivation of different species of fungi (basidiomycetes) on different substrates, being made by gravimetric analysis and visual monitoring of the composites, in order to assess that species of fungus has increased growth kinetics and its relation with different kinds of wood and then have an estimate of the potential biotic degradation of these materials. Based on results presented here, it is concluded that the Trametes villosa (TV) fungi is that best interacted with the wood contained in the composite in both species of Eucalyptus grandis (Eu) as Pinus elliottii (Pi).
Abnormalities of Masseteric Inhibitory Reflex in Hereditary Geniospasm: Evidence for a Brainstem Myoclonus
Authors: Macerollo Antonella , Saifee Tabish A. , Kassavetis Panagiotis , Pilurzi Giovanna , Schneider Susanne A. , Edwards Mark J. , Bhatia Kailash P.
Published: October 2014

We studied two unrelated families with several members suffering from geniospasm. Here, we aim to clarify the pathophysiology underlying the hereditary geniospasm through testing of brainstem excitability by the recovery cycles of the blink reflex (BR) and the masseteric inhibitory reflex (MIR). The R2 component of the BR and the SP2 component of the MIR and their recovery cycle were analyzed in 3 patients and 8 healthy, age‐matched subjects as the control group. Patients with geniospasm exhibited a different excitability of the BR, compared to the control, group, as shown by the larger R2 component area of BR in controls than patients. Notably, the mean recovery index was 0.61 ± 0.19 in geniospasm patients and 0.40 ± 0.15 in controls (P ≤ 0.05). Interestingly, the recovery cycle of the MIR showed a loss of inhibition in both patients studied, as indicated by the behavior of the SP2 component. Our cases showed a partial impairment of the activity of brainstem inhibitory interneurons, indicated by the abnormal recovery cycle of MIR. These results would implicate a mechanism akin to brainstem myoclonus for the generation of geniospasm.
Fast spin echo imaging of carotid artery dynamics
Authors: Boesen Mari E. , Maior Neto Luis A. Souto , Pulwicki Alexandra , Yerly Jerome , Lebel R. Marc , Frayne Richard
Published: October 2014

Purpose

We propose the use of a retrospectively gated cine fast spin echo (FSE) sequence for characterization of carotid artery dynamics. The aim of this study was to compare cine FSE measures of carotid dynamics with measures obtained on prospectively gated FSE images.

Methods

The common carotid arteries in 10 volunteers were imaged using two temporally resolved sequences: (i) cine FSE and (ii) prospectively gated FSE. Three raters manually traced a common carotid artery area for all cardiac phases on both sequences. Measured areas and systolic–diastolic area changes were calculated and compared. Inter‐ and intra‐rater reliability were assessed for both sequences.

Results

No significant difference between cine FSE and prospectively gated FSE areas were observed (P = 0.36). Both sequences produced repeatable cross‐sectional area measurements: inter‐rater intraclass correlation coefficient (ICC) = 0.88 on cine FSE images and 0.87 on prospectively gated FSE images. Minimum detectable difference (MDD) in systolic–diastolic area was 4.9 mm2 with cine FSE and 6.4 mm2 with prospectively gated FSE.

Conclusion

This cine FSE method produced repeatable dynamic carotid artery measurements with less artifact and greater temporal efficiency compared with prospectively gated FSE. Magn Reson Med 74:1103–1109, 2015. © 2014 Wiley Periodicals, Inc.
Retrobulbar magnetic resonance angiography using binomial off‐resonant rectangular (BORR) pulse
Authors: Ye Yongquan , Wu Zhen , Lewis Nicholas A. , Fan Qingxia , Haacke E. Mark
Published: October 2014

Purpose

Applying a newly developed binomial off‐resonant rectangular (BORR) pulse method for high resolution three‐dimensional MR angiography (MRA) on retrobulbar ocular vessels, which has not been possible with routine MRA due to background fatty tissues.

Methods

BORR pulse was implemented in a gradient echo sequence by replacing the original excitation pulse, and were optimized for robust orbital fat suppression. Several other MRA methods, with or without fat suppression, were also compared, including time‐of‐flight, contrast enhanced MRA, and hybrid of opposite‐contrast MRA. Nine healthy subjects participated with written informed consents. To reduce eye motion, the subjects were instructed to casually stare at a projected cross during each MRA scan. Major vessels were evaluated by three independent radiologists using a 4‐point scale.

Results

The BORR method yielded the best MRA results for retrobulbar vessels without contrast enhancement, significantly superior than other MRA methods. BORR results had significantly higher visibility scores than all other methods for small vessels.

Conclusion

We have successfully revealed orbital vessels in retrobulbar space for the first time using MRA, by using the BORR pulse method. With a clear depiction of the vasculature without the need for contrast enhancement, our method has the potential to provide important diagnostic information for ocular vascular diseases. Magn Reson Med 74:1050–1056, 2015. © 2014 Wiley Periodicals, Inc.
A numerical study of the influence from pre‐existing cracks on granite rock fragmentation at percussive drilling
Authors: Saadati Mahdi , Forquin Pascal , Weddfelt Kenneth , Larsson Per‐Lennart , Hild Francois
Published: October 2014

The aim of this study is to investigate the effect of pre‐existing, or structural, cracks on dynamic fragmentation of granite. Because of the complex behavior of rock materials, a continuum approach is employed relying upon a plasticity model with yield surface locus as a quadratic function of the mean pressure in the principal stress space coupled with an anisotropic damage model. In particular, Bohus granite rock is investigated, and the material parameters are chosen based on previous experiments. The equation of motion is discretized using a finite element approach, and the explicit time integration method is employed. The pre‐existing cracks are introduced in the model by considering sets of elements with negligible tensile strength that leads to their immediate failure when loaded in tension even though they still carry compressive loads as crack closure occurs because of compressive stresses. Previously performed edge‐on impact tests are reconsidered here to validate the numerical model. Percussive drilling is simulated, and the influence of the presence of pre‐existing cracks is studied. The results from the analysis with different crack lengths and orientations are compared in terms of penetration stiffness and fracture pattern. It is shown that pre‐existing cracks in all investigated cases facilitate the drilling process. Copyright © 2014 John Wiley & Sons, Ltd.
Anodic Stripping Voltammetry of Silver Nanoparticles: Aggregation Leads to Incomplete Stripping
Authors: Cloake Samantha J. , Toh Her Shuang , Lee Patricia T. , Salter Chris , Johnston Colin , Compton Richard G.
Published: October 2014

The influence of nanoparticle aggregation on anodic stripping voltammetry is reported. Dopamine‐capped silver nanoparticles were chosen as a model system, and melamine was used to induce aggregation in the nanoparticles. Through the anodic stripping of the silver nanoparticles that were aggregated to different extents, it was found that the peak area of the oxidative signal corresponding to the stripping of silver to silver(I) ions decreases with increasing aggregation. Aggregation causes incomplete stripping of the silver nanoparticles. Two possible mechanisms of ‘partial oxidation’ and ‘inactivation’ of the nanoparticles are proposed to account for this finding. Aggregation effects must be considered when anodic stripping voltammetry is used for nanoparticle detection and quantification. Hence, drop casting, which is known to lead to aggregation, is not encouraged for preparing electrodes for analytical purposes.
Bildqualität ist nicht alles
Authors: Konopka Bernd
Published: October 2014

Kameras für Anwendungen in der Videoüberwachung müssen nicht nur qualitativ hochwertige Bilder liefern, sondern auch eine effiziente Übertragung und Speicherung dieser Bilder erlauben. Ein wesentliches Kriterium ist daher die eigene Intelligenz der Kamera, mit der sich dynamisch zu jedem Zeitpunkt die beste Balance aus Dateigröße und Bildqualität finden lässt.
Gute Aussichten für die Photonik
Authors: Löffler Annika
Published: October 2014

Die Schlüsseltechnologie Photonik blickt positiv in die Zukunft: bis zum Jahr 2020 soll das Weltmarktvolumen des Technologiefelds auf rund 615 Milliarden Euro ansteigen, wie die Branchenfachverbände VDMA, Spectaris und ZVEI sowie das Bundesministerium für Bildung und Forschung BMBF im 2013 erstmals vorgestellten „Branchenreport Photonik”︁ erwarten. Dies entspricht einem durchschnittlichen jährlichen Wachstum mindestens anderthalb Mal so hoch wie das Wachstum des weltweiten Bruttoinlandsprodukts, basierend auf einem unterstellten Weltmarktvolumen von rund 350 Milliarden Euro in 2011.
Janus hybrid hairy nanoparticles
Authors: Zhou Tian , Dong Bin , Qi Hao , Mei Shan , Li Christopher Y.
Published: October 2014

Janus hairy nanoparticles (JHNPs) represent a new class of hybrid materials with a nanoparticle core and a layer of bicompartmentalized polymer brushes. This unique structure combines the complex properties of polymer brushes, the amphiphilic nature of surfactant, and the mechanical, optical, and electronic properties of nanoparticles. Over the past decade, tremendous efforts have been devoted to synthesizing JHNPs and understanding their structure and properties. In this review, we will summarize the recent progresses in the field, including fabrication approaches and the self‐ and directed assembly behavior of such JHNPs. We will specifically focus on the newly developed polymer single crystal directed nanoparticle assembly approach. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1620–1640
Organic‐inorganic nanocomposites composed of conjugated polymers and semiconductor nanocrystals for photovoltaics
Authors: Jung Jaehan , Yoon Young Jun , He Ming , Lin Zhiqun
Published: October 2014

Semiconductor organic‐inorganic nanocomposites have garnered much attention as they integrate the advantageous properties from conjugated polymers (CPs) and semiconductor nanocrystals (NCs). Recent developments in interfacial engineering of CP‐NC nanocomposites enabled the intimate contact between CPs and NCs, thereby facilitating charge separation between these two constituents. To capitalize on the use of CP‐NC nanocomposites for hybrid solar cells, several issues need to be addressed, including materials design and engineering, light harvesting, and morphology of photoactive layer. In this Review, the general working principle of hybrid solar cells and the development of p‐type and n‐type CPs are briefly introduced, followed by the highlight of recent advances in synthesis of CP‐NC nanocomposites in which CP and NC are in intimate contact for hybrid solar cells, and the discussion on various strategies for potentially improved power conversion efficiency. An outlook for future directions in this area is also presented. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1641–1660
Effect of Vegetation Cover on the Ground Thermal Regime of Wooded and Non‐Wooded Palsas
Authors: Jean Mélanie , Payette Serge
Published: October 2014

Although warming air temperatures are contributing to permafrost degradation across the circumpolar zone, understanding of permafrost and environmental feedbacks to climate change is limited. Palsas can be used as indicators of permafrost stability given their sensitivity to changes in temperature and precipitation. However, field observations on the effects of vegetation cover are needed to compare permafrost dynamics of wooded and non‐wooded palsas. This study examined the influence of vegetation on the soil thermal regime of wooded palsas covered by black spruce trees and non‐wooded palsas covered by shrubs in discontinuous permafrost of the Boniface River area of northern Quebec, Canada. It investigated the effects of organic layer thickness, vegetation and snow depth on soil temperature at 50 cm and 100 cm depths for over 2 years. The coldest summer soil temperatures were associated with thick organic layers. In summer, soil temperatures were colder under spruce stands than under shrub canopies and forest openings, whereas the thick snow cover in spruce stands and forest openings maintained warmer winter soil temperatures than under shrub canopies. Well‐defined zero‐curtain periods during fall and spring could be an early indicator of current changes in the soil thermal regime of palsas. At the northern edge of discontinuous permafrost, non‐wooded palsas have the most favourable conditions for permafrost stability, because heterogeneous vegetation cover on wooded palsas promotes snow trapping and lateral heat transfer. Vegetation types should be considered in estimating future rates of permafrost degradation. Copyright © 2014 John Wiley & Sons, Ltd.
Nasal NO as a biomarker: Don't say NO to the many challenges of translational medicine
Authors: Voynow Judith A. , Montpetit Alison J.
Published: October 2014

This editorial summarizes the challenges of exhaled breath biomarker research particularly for nasal NO. We also introduce a new focus for Pediatric Pulmonology, a section on Translational Medicine. Pediatr Pulmonol. 2015; 50:100–102. © 2014 Wiley Periodicals, Inc.
Analysis of Polar Precursors of 1,3,5,7‐Tetranitro‐1,3,5,7‐tetrazocine (HMX) Using Hydrophilic Interaction Chromatography
Authors: Zhu Chao , Meng Zihui , Xu Zhibin , Xue Min , Wang Fengyan , Liu Yue , Lin Zhihui , Qin Guangmin , Ge Zhongxue , Wang Bozhou
Published: October 2014

Octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) is currently one of the most widely used explosives. 1,3,5,7‐Tetraacetyl‐1,3,5,7‐tetraazacyclooctane (TAT) is an attractive precursor for the synthesis of HMX; the nitration of this key precursor results in both high yield and purity under mild condition. TAT can be prepared either by acetylation of 2,6‐diacetyl‐pentamethylenetetramine (DAPT) or by the condensation of ACN and 1,3,5‐trioxane. However, TAT and DAPT are polar compounds, and are difficult to analyze using reverse phase liquid chromatography. Herein, a chromatography method for the direct separation of these polar compounds was developed using hydrophilic interaction chromatography (HILIC) using a Venusil HILIC column, with ACN/water (95/5, v/v) as the mobile phase. The chromatographic analysis and identification of these polar compounds provide valuable information for the optimization of the synthetic process of TAT.
Modelling the Emergence of Shared Attitudes from Group Dynamics Using an Agent‐Based Model of Social Comparison Theory
Authors: Van Rooy Dirk , Wood Ian , Tran Eric
Published: October 2014

We propose a novel agent‐based implementation of Festinger's social comparison theory (SCT). The social comparison model (SCM) consists of connectionist networks that simulate agent‐level social comparison processes. Agent networks are combined into an adaptive network structure that is shaped by social comparisons between individual agents. Simulations show how the SCM produces behavior consistent with the empirical literature on group dynamics. In addition, experimental results are reported that show how the SCM can simulate how critical and conformist norms affect interpersonal processes and emergent attitudes. We conclude that the coupling of simulations and experiments, and the use of psychologically plausible agent models within adaptive network structures, can provide new impetus to the development of models of individual and social cognition. An integrated framework such as the SCM allows investigating key theoretical predictions around the origin and maintenance of socially shared information through social comparisons in fundamentally novel ways. Copyright © 2014 John Wiley & Sons, Ltd.
6,6‐Dicyanopentafulvenes: Teaching an Old Dog New Tricks
Authors: Finke Aaron D. , Diederich François
Published: October 2014

6,6‐Dicyanopentafulvene (DCF) is a fascinating molecular entity that consists of a cyclopentadiene ring conjugated to an exocyclic double bond bearing two cyano groups on its periphery. Herein, we give a brief history of the chemistry of DCFs prior to our arrival to the field in 2011, followed by a summary of our work. We show how substitution on the ring and the exocyclic bond affects the HOMO and LUMO energies of pentafulvenes and how the design of DCFs was exploited computationally for the first time. Shortly after the report of the first rational synthesis of DCFs, we discovered that DCFs had a vast and astonishing array of reactivities to form new molecular entities. Simple, catalyst‐free reactions between DCF acceptors and electron‐rich donors led to the formation of scaffolds of exceptional complexity. Furthermore, our discovery that DCFs are capable of undergoing mild pentafulvene‐to‐benzene rearrangements challenges previous conventions of fulvene chemistry.

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Lapland longspur mortality at an oil well drilling rig site, Laramie County, Wyoming
Authors: Ramirez Pedro , Dickerson Kimberly , Lindstrom Jim , Meteyer Carol U. , Darrah Scott
Published: October 2014

Two hundred fifty‐one Lapland longspur (Calcarius lapponicus) carcasses were recovered around an oil well drilling rig in Laramie County, Wyoming, USA, on December 13–14, 2010, apparent victims of a winter storm and “light entrapment” from the lights on the drilling rig during foggy conditions. We found Lapland longspur carcasses distributed around the drilling rig from 33 m to 171 m. Investigators did not find evidence of bird carcasses on the drilling rig deck or equipment immediately adjacent to the drilling rig. We ruled out chemical toxins and disease as a cause of mortality. Weather conditions, the circular depositional pattern of carcasses around the drilling rig, and bird necropsy results led investigators to conclude that the Lapland longspur mortality was the result of the migrating birds entering the area illuminated by the drilling rig lights in freezing fog and the birds repeatedly circling the drilling rig until they fell to the ground in exhaustion and dying from subsequent trauma. Further research is needed to understand how to most effectively adjust lighting of onshore drilling rigs to reduce the potential for avian light entrapment. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Une morphologie de la circulation des savoirs la revue depuis 1800
Authors: Tesnière Valérie , Bouquin Corinne
Published: October 2014

L'enquête portant sur 1 385 titres, commençant parannales,journalou revue, a pour but de cerner l'évolution en France des revues « à caractère scientifique », du XIXesiècle à aujourd'hui. Elle permet de retracer sur deux siècles l'essor de la production et les périodes de reflux, d'insérer les titres scientifiques dans un contexte plus large de production éditoriale et d'insister sur l'importance de la fonction de circulation des idées et de l'information, par l'analyse croisée des rythmes de parution et de la courbe de croissance.
Les revues médicales depuis 1800
Authors: Tesnière Valérie , Cantau Alina
Published: October 2014

Les revues médicales arrivent en tête dans l'enquête statistique (15,4%). Principal outil de communication, représentant un marché éditorial conséquent lié à l'essor de la discipline médicale au XIXe siècle, la revue n'illustre cependant pas que la montée en puissance des spécialités. Outre l'importance d'une circulation rapide de l'information (prépondérance du mensuel), l'analyse de la production éditoriale souligne l'intrication complexe de la médecine généraliste et des spécialités avec les préoccupations de santé publique et de formation professionnelle.
Irreversible hyperoxidation of peroxiredoxin 2 is caused by tert‐butyl hydroperoxide in human red blood cells
Authors: Ishida Y.I. , Takikawa M. , Suzuki T. , Nagahama M. , Ogasawara Y.
Published: October 2014

Peroxiredoxin 2 (Prx2) is the third most abundant protein in red blood cells (RBCs). In this study, we have succeeded in implementing the rapid and simultaneous detection of the hyperoxidized (Prx2‐SO2/3) and reduced (Prx2‐SH) forms of Prx2 in human RBCs using reverse phase high‐performance liquid chromatography. The detection of a peak corresponding to Prx2‐SO2/3 was clearly observed following treatment of tert‐butyl hydroperoxide (t‐BHP), but not H2O2, and was found to be dose‐dependent. The identity of the peak was confirmed as Prx2 by immunoblotting and mass spectrometry analysis. Our results suggest that t‐BHP hyperoxidizes cysteine residues in Prx2 more readily than H2O2, and that accumulation of hyperoxidized Prx2 might reflect disruption of redox homeostasis in RBCs.
PHF21B as a candidate tumor suppressor gene in head and neck squamous cell carcinomas
Authors: Bertonha Fernanda Bernardi , Barros Filho Mateus de Camargo , Kuasne Hellen , dos Reis Patricia Pintor , da Costa Prando Erika , Muñoz Juan José Augusto Moyano , Roffé Martín , Hajj Glaucia Noeli Maroso , Kowalski Luiz Paulo , Rainho Claudia Aparecida , Rogatto Silvia Regina
Published: October 2014

A significant association between DNA losses on 22q13.31 and head and neck squamous cell carcinomas (HNSCC) was previously reported by our group. Our data indicated that PHF21B gene, mapped on 22q13.31 and encoding a protein with function of chromatin‐mediated transcriptional regulation, might be a putative tumor suppressor gene. To test this hypothesis, gene copy number was assessed in 75 HNSCC and 49 matched peripheral blood samples. PHF21B losses were detected in 43 tumors and were significantly associated with patients with familial history of cancer (P < 0.0001); i.e., 36/43 cases showed a positive family history of cancer and 22/36 had first‐degree relatives with cancer (P = 0.049). In attempt to investigate other mechanisms for PHF21B loss of function, DNA sequencing was performed and no mutations were detected. We next evaluated the gene expression levels after inhibition of DNA methylation in nine HNSCC and breast carcinoma cell lines. Additionally, PHF21B expression levels were evaluated in colon cancer HCT116 cells as well as in its counterpart DKO (double knockout of DNMT1 and DNMT3B). The higher expression levels of PHF21B gene detected in DKO cells were inversely correlated with the DNA methylation. Further, DNA methylation in the specific promoter‐associated CpG Island was investigated. Interestingly, gene hypermethylation was detected in 13/37 tumors: 5/13 HNSCC cases had family history of cancer in first‐degree relatives and 8/13 showed both, DNA methylation and PHF21B losses in the tumor sample. One patient had PHF21B loss in the peripheral blood cells and PHF21B methylation in the tumor sample. Additionally, overexpression of PHF21B in cell lines drastically reduces clonogenic and migratory abilities. These data suggest that PHF21B is a novel tumor suppressor gene that can be inactivated by genetic and epigenetic mechanisms in the human cancer.
Development of pharmacodynamic biomarkers for ATR inhibitors
Authors: Chen Tao , Middleton Fiona K. , Falcon Susanna , Reaper Philip M. , Pollard John R. , Curtin Nicola J.
Published: October 2014

Background

ATR, which signals DNA damage to S/G2 cell cycle checkpoints and for repair, is an attractive target in cancer therapy. ATR inhibitors are being developed and a pharmacodynamic assay is needed to support clinical studies.

Methods

Phosphorylation of ATR targets, Chk1 and H2AX, was evaluated in MCF7 and K562 cells, human volunteer PBMCs and whole blood by Western blot, immunofluorescence microscopy and flow cytometry after DNA damage. The effect of cell cycle phase, ATR knockdown and inhibition on these phosphorylation events was determined.

Results

Hydroxyurea, UV and 4NQO induced Chk1 and H2AX phosphorylation in MCF7 and K562 cells. UV/4NQO activation of ATR was detectable in non‐cycling cells. Chk1 phosphorylation was reduced by ATR knockdown and reflects ATR activity for 3 h, H2AX phosphorylation after UV/4NQO is ATR‐dependent for 1 h but increasingly ATM and DNA‐PK‐dependent at later time points. In isolated PBMCs both phospho‐targets were detectable after UV/4NQO but in PBMCs from whole blood treated with 4NQO only H2AX was detectable.

Conclusion

PhosphoChk1 and H2AX are useful biomarkers for ATR inhibition using a variety of immuno‐detection methods, but timing may be critical. Importantly, ATR activity is detectable in non‐cycling PBMCs allowing them to be used as a surrogate tissue for biomarker measurement. In PBMCs from whole blood treated with 4NQO phosphoH2AX was the most useful biomarker of ATR activity and a clinically viable pharmacodynamic assay for ATR inhibitors has been developed.
Policy transfer, neo-liberalism or coercive institutional isomorphism? Explaining the emergence of a regulatory regime for quality assurance in the Hong Kong higher education sector
Authors: Jarvis Darryl S L
Published: October 2014

abstract

The spread of quality assurance (QA) regimes in higher education has been an explosive phenomenon over the last 25 years. By one estimate, for example, half of all the countries in the world have adopted QA systems or QA regulatory agencies to oversee their higher education sector. Typically, this phenomenon is explained as a process of policy diffusion, the advent of marketization, the spread of neoliberalism, massification and, concomitantly, the emergence of a ‘global market’ for higher education, prompting governments to respond by validating standards, quality, and introducing certification and compliance regimes. In this paper I question the utility of these explanatory frameworks, specifically looking at the case of Hong Kong in order to explore the role coercive institutional isomorphism plays in policy adoption and the implications of this for regulatory performativity.
In vitro disappearance characteristics of selected categories of commercially available dog treats
Authors: de Godoy Maria R. C. , Vermillion Ryan , Bauer Laura L. , Yamka Ryan , Frantz Nolan , Jia Tim , Fahey George C. , Swanson Kelly S.
Published: October 2014

Pet owners desire treats with adequate nutritional profiles, functional benefits, long-lasting properties and an interactive nature. Therefore, it is pivotal to understand the digestion characteristics of treats produced by different processing methods and having variable nutritional composition. The objective of the present study was to measure in vitro disappearance characteristics of selected categories of commercially available treats. In vitro procedures developed by Boisen and Eggum in 1991 were modified to handle larger sample sizes. Treat samples were evaluated in triplicate. Following incubation, in vitro DM disappearance (DMD) was calculated. In vitro DMD of selected treats varied widely. For the gastric phase, DMD ranged from 6·9 to 88·8 %, whereas intestinal phase digestion resulted in a DMD range of 10·7–100·0 % (P < 0·05). Because of differences in treat composition and size, they were divided into six categories: Biscuit, Bone, Chew, Dental, Meat Product and Rawhide. In general, Bone was the least digestible treat category in both gastric and intestinal phases. Meat Product and Rawhide treats had a DMD of 71·5–100 % after the intestinal phase, whereas Biscuit had values above 93 %. Chew and Dental treats had a wide DMD range (54·5–100 %). Understanding the DMD of commercially available treats is important to verify their safety for consumption and potential digestibility once ingested. These data indicate wide variation in DMD among and within different treat categories. This information will assist pet food sale associates, pet owners and veterinarians to make more educated decisions when it relates to selection and recommendations about commercially available treats. Future work is needed to expand the knowledge on in vitro DMD and safety of treats and to further investigate their impact on in vivo DM digestibility once fed to dogs.
Party Cohesion in Westminster Systems: Inducements, Replacement and Discipline in the House of Commons, 1836–1910
Authors: Eggers Andrew C. , Spirling Arthur
Published: October 2014

This article considers the historical development of a characteristic crucial for the functioning and normative appeal of Westminster systems: cohesive legislative parties. It gathers the universe of the 20,000 parliamentary divisions that took place between 1836 and 1910 in the British House of Commons, construct a voting record for every Member of Parliament (MP) serving during this time, and conducts analysis that aims to both describe and explain the development of cohesive party voting. In line with previous work, it shows that – with the exception of a chaotic period in the 1840s and 1850s – median discipline was always high and increased throughout the century. The study uses novel methods to demonstrate that much of the rise in cohesion results from the elimination of a rebellious ‘left tail’ from the 1860s onwards, rather than central tendency shifts. In explaining the aggregate trends, the article uses panel data techniques and notes that there is scant evidence for ‘replacement’ explanations that involve new members behaving in more disciplined ways than those leaving the chamber. It offers evidence that more loyal MPs were more likely to obtain ministerial posts, and speculates that this and other ‘inducement’-based accounts offer more promising explanations of increasingly cohesive parties.
The Power of the Dark Side: Negative Partisanship and Political Behaviour in Canada
Authors: Caruana Nicholas J. , McGregor R. Michael , Stephenson Laura B.
Published: October 2014

The origins and implications of partisan identification are well-studied, but negative partisan attitudes—dislike for a particular party—have escaped such scrutiny, even as the politics of negativity enjoys sustained popularity, especially come election time. In this paper we build upon the comparatively modest negative partisanship literature to consider the effects of negative partisan attitudes on a range of political behaviours. There are reasons to suspect that negative and positive partisanship may have different effects; thus, accounting for the unique influence of negative attitudes is important for understanding the full effect of partisanship on political behaviour. Our results, based upon Canadian Election Study data from 2008 and 2011, reveal that, in addition to vote choice, negative partisanship influences voter turnout and a range of political activities, both related and unrelated to parties. These findings provide evidence of the power of the “dark side” of partisanship.
Genome-wide copy number scan identifies IRF6 involvement in Van der Woude syndrome in an Indian family
Authors: MANJEGOWDA DINESH S. , PRASAD MANU , VEERAPPA AVINASH M. , RAMACHANDRA NALLUR B.
Published: October 2014

Van der Woude syndrome (VWS) is an autosomal dominant developmental malformation presenting with bilateral lower lip pits related to cleft lip, cleft palate and other malformations. We performed a whole-genome copy number variations (CNVs) scan in an Indian family with members suffering from VWS using 2·6 million combined SNP and CNV markers. We found CNVs affecting IRF6, a known candidate gene for VWS, in all three cases, while none of the non-VWS members showed any CNVs in the IRF6 region. The duplications and deletions of the chromosomal critical region in 1q32–q41 confirm the involvement of CNVs in IRF6 in South Indian VWS patients. Molecular network analysis of these and other cleft lip/palate related module genes suggests that they are associated with cytokine-mediated signalling pathways and response to interferon-gamma mediated signalling pathways. This is a maiden study indicating the involvement of CNVs in IRF6 in causing VWS in the Indian population.
Simulation and design of pre-ionization systems for Alborz tokamak
Authors: Shahshenas Shiva , Amrollahi Reza
Published: October 2014

Alborz tokamak is an educational system for studying plasma phenomena in many physics and engineering experiments. A hot filament and a reverse discharge loop are used in the tokamak as the pre-ionization system. The hot cathode prepares a local initial electron density, then the reverse discharge loop trigger the ionization avalanche by means of inducing a toroidal electric field. The parameters of the hot filament are determined in order to produce the desired electron source. Filament temperature is simulated by using three-dimensional finite element method. The average values of filament temperature and electron density at the plasma core (at the end of pre-ionization process) were calculated and are about 2750 K and 1019m−3, respectively. The resultant electron density and equivalent plasma resistivity due to reverse discharge loop are also calculated. In this paper, the simulation results, optimum structural style, the obtained parameters, the temperature of different parts of the filament and produced electron density are presented and discussed.
Human-related factors regulate the presence of domestic dogs in protected areas
Authors: Soto Carolina A. , Palomares Francisco
Published: October 2014

The presence of domestic species such as dogsCanis familiarisin protected areas can cause problems for native species as a result of competition, predation and disease transmission. To improve our ability to design effective control policies we investigated the factors affecting detection of dog tracks in a Mediterranean national park.

We investigated the presence of dogs across 69 2 × 2 km grid squares in Doñana National Park in south-west Spain and used logistic regression models to analyse the associated environmental and human constraints. We did not detect dogs in areas away from the edges of the national park close to human settlements (track census effort > 470 km) and the detection of dog tracks was correlated with human presence. We conclude that domestic dogs occasionally enter the Park from the surrounding area and are a direct threat to wildlife at the edges of the Park. Management actions to reduce the effects of domestic dogs in protected areas where feral dog populations are not established should focus on the spatial extent of local settlements, regulation and awareness-raising to encourage responsible dog-ownership, and control measures such as removing un-owned dogs from boundaries and areas close to human dwellings, and forbidding unleashed dogs in public facilities.
‘Ironman’: Joseph Daniels and the white history of South Africa's deep south
Authors: van Sittert Lance
Published: October 2014

Polar history has historically been white history, nowhere more so than in South Africa, The recent attempt to imagine a post-apartheid deep south through the public recovery of a black boatman who drowned in the annexation of the Prince Edward Islands in 1948 has ironically left the white history largely intact. Re-reading the annexation not as ceremony and survey, but as labour calls the central claims of this white history into question; that the annexation was a triumph of white seamanship not black stevedoring; that Daniels’ death was a tragic accident not a result of racism; and that black labour was merely the manual appendage to white intellects. It reveals that the landing of 300 tons of cargo by black boatmen. was what enabled the ‘effective occupation’ of the islands. Daniels death was the avoidable result of an institutional racism that discounted the lives of black labour and exposed them at Marion Island to the dangerous work conditions of long hours in open boats in rough sea without adequate safety provisions; and that Daniels was a boatman, not an ‘unskilled labourer’, with a tradition of co-adventuring that valued an individual for their strength, skill and courage, not the colour of their skin and in which the individual was defined by their contribution to the group
Three-dimensional electromagnetic simulation of monolithic radial transmission lines for Z-pinch
Authors: Mao Chongyang , Zou Xiaobing , Wang Xinxin
Published: October 2014

The electromagnetic simulation of the monolithic radial transmission lines for future Z-pinch was performed. Focusing on the difference in the maximum transmitted power efficiency between the electromagnetic simulation and the circuit simulation, the monolithic radial transmission lines with different impedance profile (exponential, Gaussian, hyperbolic) were compared. The power efficiency for the exponential line is higher than that for the Gaussian lines and the hyperbolic line, which is similar to that from the circuit simulation. However, all the power efficiencies obtained with the electromagnetic simulation are about 15% lower than those obtained with the circuit simulation, indicating the existence of considerable non-TEM modes and a non-ignorable error in the circuit simulation based on the quasi-TEM mode approximation. In consideration of several monolithic radial transmission lines being stacked together and the flat electrodes required by the stacked lines, the hyperbolic line was compared with the exponential line with several wide radial slots cut on the flat electrodes. While the hyperbolic line has a little bit lower transmitted power efficiency than that of the exponential line, it is much easier in fabrication. For this reason, the hyperbolic line was recommended as the best choice.
Simplicial localisation of homotopy algebras over a prop
Authors: YALIN SINAN
Published: October 2014

We prove that a weak equivalence between two cofibrant (colored) props in chain complexes induces a Dwyer–Kan equivalence between the simplicial localisations of the associated categories of algebras. This homotopy invariance under base change implies that the homotopy category of homotopy algebras over a propPdoes not depend on the choice of a cofibrant resolution ofP, and gives thus a coherence to the notion of algebra up to homotopy in this setting. The result is established more generally for algebras in combinatorial monoidal dg categories.
Risk factors associated with an outbreak of dengue fever/dengue haemorrhagic fever in Hanoi, Vietnam
Authors: TOAN D. T. T. , HOAT L. N. , HU W. , WRIGHT P. , MARTENS P.
Published: October 2014

Dengue fever/dengue haemorrhagic fever (DF/DHF) appears to be emerging in Hanoi in recent years. A case-control study was performed to investigate risk factors for the development of DF/DHF in Hanoi. A total of 73 patients with DF/DHF and 73 control patients were included in the study. The risk factor analysis indicated that living in rented housing, living near uncovered sewers, and living in a house discharging sewage directly into to ponds were all significantly associated with DF/DHF. People living in rented houses were 2·2 times more at risk of DF/DHF than those living in their own homes [adjusted odds ratio (aOR) 2·2, 95% confidence interval (CI) 1·1–4·6]. People living in an unhygienic house, or in a house discharging sewage directly to the ponds were 3·4 times and 4·3 times, respectively, more likely to be associated with DF/DHF (aOR 3·4, 95% CI 1–11·7; aOR 4·3, 95% CI 1·1–16·9). These results contribute to the understanding of the dynamics of dengue transmission in Hanoi, which is needed to implement dengue prevention and control programmes effectively and efficiently.