bluuebunny/crossref_metadata_2025 huggingface dataset:
Patients with recurrent biliary tract cancer have a better prognosis than those with unresectable disease: retrospective analysis of a multi‐institutional experience with patients of advanced biliary tract cancer who received palliative chemotherapy
Authors: Ikezawa Kenji , Kanai Masashi , Ajiki Tetsuo , Tsukamoto Tadashi , Toyokawa Hideyoshi , Terajima Hiroaki , Furuyama Hiroaki , Nagano Hiroaki , Ikai Iwao , Kuroda Nobukazu , Awane Masaaki , Ochiai Toshiya , Takemura Shigekazu , Miyamoto Atsushi , Kume Makoto , Ogawa Masao , Takeda Yutaka , Taira Kaoru , Ioka Tatsuya
Published: June 2013

Background

Prognostic factors for patients with advanced biliary tract cancer (BTC) who received palliative chemotherapy have not been fully established. Especially, the status of unresectable/recurrent disease has not been well studied because of a small number of patients with recurrent BTC in previous studies.

Methods

This multicenter retrospective study was conducted in 18 institutions in Japan. We retrospectively reviewed data regarding 403 patients with pathologically proven BTC who received palliative chemotherapy between April 2006 and March 2009. One hundred and ninety‐two patients with recurrent BTC were included. Univariate and multivariate analyses were performed to identify prognostic factors.

Results

The median overall survival was significantly longer in the recurrent BTC patients than in the unresectable BTC patients (398 days vs. 323 days, P = 0.004). After adjustment using multivariate analysis, the status of recurrent/unresectable disease remained an independent prognostic factor (hazard ratio 1.33, 95% confidence interval 1.04–1.70, P = 0.022) in addition to performance status, extent of disease, carbohydrate antigen 19‐9 levels, and carcinoembryonic antigen levels.

Conclusions

The status of unresectable/recurrent disease was shown as an independent prognostic factor in the BTC patients. This result may help to predict life expectancy of BTC patients and design future clinical trials evaluating palliative chemotherapy in BTC.
An extended dysfunctional area in the congestive area of the remnant liver after hemi‐hepatectomy with middle hepatic vein resection for liver cancers evaluated on the gadoxetic acid disodium‐enhanced magnetic resonance imaging
Authors: Mu Han , Ariizumi Shunichi , Katagiri Satoshi , Egawa Hiroto , Yamamoto Masakazu
Published: June 2013

Background

The aim of the present study was to evaluate the liver function in the congestive area of the remnant liver after hemi‐hepatectomy with middle hepatic vein (MHV) resection for liver cancers.

Methods

From November 2009 through December 2012, 18 patients underwent hemi‐hepatectomy including the MHV for liver cancers. Post‐hepatectomy, the volume of the congestive area, which appeared as a hyper‐intense area on T2‐weighted images and dysfunctional area, which appeared as a low intensity area on hepatobiliary phase images in the remnant liver was evaluated in all patients by gadoxetic acid disodium‐enhanced magnetic resonance imaging.

Results

Fifteen of 18 patients showed a congestive area, and 16 of 18 patients showed a dysfunctional area in the remnant liver. The dysfunctional rate (median 11%) was significantly larger than the congestive rate (median 5%, P = 0.0004). The dysfunctional rate was associated with tumor invasion to the root of the MHV, and no tumor invasion to the root of the MHV was identified as a significant predictor of a larger dysfunctional area (odds ratio 25.888, P = 0.0267) on multivariate analysis.

Conclusion

Hemi‐hepatectomy with MHV resection for liver cancers should be performed considering the dysfunctional area in the remnant liver, which is associated with tumor invasion to the root of the MHV.
The supervisor POS–LMX–subordinate POS chain: Moderation by reciprocation wariness and supervisor's organizational embodiment
Authors: Eisenberger Robert , Shoss Mindy Krischer , Karagonlar Gökhan , Gonzalez‐Morales M. Gloria , Wickham Robert E. , Buffardi Louis C.
Published: June 2013

We present three studies providing an increased understanding of the interdependence between perceived organizational support (POS) and leader–member exchange (LMX). Using employees from a social service agency and new hires from a variety of organizations, we report evidence for a relational chain leading from supervisors' perceptions of support by the organization (supervisor POS) to the formation of high‐quality LMX relationships with their subordinates (first link), who interpret high‐quality LMX as support from the organization (subordinate POS, second link) and, ultimately, repay the organization with increased dedication and effort (examined here in terms of reduced withdrawal behavior). The relationship between supervisor POS and LMX with subordinates was strongly moderated by supervisor fear of exploitation in exchange relationships (reciprocation wariness), holding only for supervisors with low reciprocation wariness. Consistent with the view that employees perceive the organization as partly responsible for treatment received from supervisors, LMX was found to be more strongly related to POS when employees highly identified their supervisors with the organization (supervisor's organizational embodiment), and this interaction extended to reduced withdrawal behavior. Copyright © 2013 John Wiley & Sons, Ltd.
Dry corrosion of the aluminium alloy (EN AC‐48100), influence of temperature, ethanol and water content
Authors: Tuchscheerer F. , Krüger L. , Mandel M. , Müller S. , Liebsch S.
Published: June 2013

Die korrosiven Eigenschaften der Aluminiumlegierung EN AC‐48100 (Al‐17wt%Si‐4wt%Cu‐Mg) wurden in ethanolhaltigen Kraftstoffen bei verschiedenen Wassergehalten (0,05 Vol.‐%, 0,2 Vol.‐%, 0,35 Vol.‐%), Temperaturen (20°, 60°C, 80°C) und Ethanolgehalten (10 Vol.‐%, 25 Vol.‐%, 50 Vol.‐%, 85 Vol.‐%) untersucht. Dabei konnte eine starke Abhängigkeit der Alkoholatkorrosion vom Wassergehalt und der Temperatur festgestellt werden. Bei einem Wasseranteil von 0,05 Vol.‐% im Ethanolkraftstoff und einer Kraftstofftemperatur von 80°C kommt es bereits nach kurzer Zeit zu starker Korrosion. Bei geringen Ethanolkonzentrationen wird die Korrosion in hohem Maße durch den Ethanolgehalt beeinflusst. Ab 25 Vol.‐% Ethanol im Kraftstoff ist der Einfluss der Ethanolkonzentration auf den durch Korrosion verursachten Masseverlust gering. Aufgrund der Beobachtungen und Messungen wurde eine Theorie zur Ursache des mehrstufigen Charakters des auftretenden Korrosionsmechanismus entwickelt.
Nanoparticle‐based chemical exchange saturation transfer (CEST) agents
Authors: Castelli Daniela Delli , Terreno Enzo , Longo Dario , Aime Silvio
Published: June 2013

The frequency‐encoding property of chemical exchange saturation transfer (CEST) agents places them in a unique position among the MRI contrast agents, as it allows the visualization of more agents in the same MR image, as well as making it possible to set up innovative MRI‐responsive agents. The sensitivity issue shown by molecular CEST agents (either diamagnetic or paramagnetic) has been tackled with the design of nanoparticle‐based CEST agents endowed with a large number of exchangeable protons that ensure large saturation transfer levels. Several systems have been considered, namely supramolecular adducts, dendrimers, micelles and liposomes loaded with CEST agents (in most cases, paramagnetic CEST agents). A particularly sensitive system is represented by lipoCEST agents, consisting of liposomes whose inner water resonance is shifted by the co‐presence of paramagnetic lanthanide complexes. The exchangeable pool of protons is represented by all the water molecules contained in the inner liposome cavity (106–108). Although in vitro work has provided excellent results, in vivo translation appears to be hampered to some extent by the peculiar behavior shown by these particles on administration to living animals. Copyright © 2013 John Wiley & Sons, Ltd.
Adolescent suicidal behavior across the excess weight status spectrum
Authors: Zeller Meg H. , Reiter‐Purtill Jennifer , Jenkins Todd M. , Ratcliff Megan B.
Published: June 2013

Objective:

Relative suicidal behavioral risks (ideation, attempts) for overweight, obese, and extremely obese adolescents (vs. healthy weight) and who did/did not accurately perceive themselves as overweight were examined in this study.

Design and Methods:

A new variable (weight status/accuracy) was computed that combined actual weight status (based on BMI) with weight perception accuracy. To evaluate the effect of weight status/accuracy on each suicidal risk behavior, logistic regression was performed to calculate odds‐ratios and 95% confidence intervals (CI). Potential model covariates included gender, age, race, survey year, and whether they had felt sad/hopeless.

Results:

Weight perception accuracy increased as the degree of excess weight increased. Relative to healthy weight, being obese or extremely obese (but not overweight) was associated with significantly greater risk for adolescent engagement in suicidal ideation, but was unrelated to suicide attempts. Adolescents in all excess weight categories who were accurate in their weight perception were at significantly greater odds of suicidal ideation, whereas those who were inaccurate were of no greater odds of suicidal ideation than healthy weight youth who accurately perceived their weight. Findings regarding suicide attempts varied based on actual weight/weight perception accuracy and race/ethnicity.

Conclusion:

The present findings are both important and clinically relevant. While widely accepted that there are multiple pathways to suicide, our understanding of adolescent suicidal behavior risks and accordingly, prevention efforts, will be informed by comprehensive prospective studies that should also, from here forward, consider categorization of the entire weight spectrum (e.g., extreme obesity).
Anti‐hypertensive treatment preserves appetite suppression while preventing cardiovascular adverse effects of tesofensine in rats
Authors: Bentzen Bo Hjorth , Grunnet Morten , Hyveled‐Nielsen Lars , Sundgreen Claus , Lassen Jørgen Buus , Hansen Henrik H.
Published: June 2013

Objective:

Tesofensine is a novel triple monoamine reuptake inhibitor which is in development for the treatment of obesity. Preclinical and clinical data suggest that appetite suppression is an important mechanism by which tesofensine exerts its robust weight reducing effect. Notably, the strong hypophagic response to tesofensine treatment is demonstrated to be linked to central stimulation of noradrenergic and dopaminergic neurotransmission. The sympathomimetic mode of action of tesofensine may also associate with the elevated heart rate and blood pressure observed in clinical settings, and we therefore sought experimentally to address this issue.

Design and Methods:

The anorexigenic and cardiovascular effects of tesofensine were studied simultaneously in telemetrized conscious rats in a combined real‐time food intake and cardiovascular telemetry monitoring system.

Results:

Acute administration of tesofensine caused a dose‐dependent hypophagic effect as well as increased heart rate and blood pressure. Interestingly, combined treatment with metoprolol (b1 adrenoceptor blocker, 10‐20 mg/kg, p.o.) fully prevented the cardiovascular sympathetic effects of tesofensine while leaving the robust inhibitory efficacy on food intake unaffected. Similarly, the angiotensin AT1 receptor antagonist telmisartan (1.0‐3.0 mg/kg, p.o.) did not interfere with the anti‐obesity effects of tesofensine, however, telmisartan only partially reversed the increase in systolic blood pressure and had no effect on the elevated heart rate induced by tesofensine.

Conclusion:

These data suggests that tesofensine causes elevations in heart rate and blood pressure by increasing sympathetic activity, and that different adrenoceptor subtypes may be responsible for the anti‐obesity and cardiovascular effects of tesofensine.
An intercomparison of subgrid models for large‐eddy simulation of katabatic flows
Authors: Smith Craig M. , Porté‐Agel Fernando
Published: June 2013

We present an intercomparison of three subgrid‐scale (SGS) models for large‐eddy simulation (LES) of katabatic flows. The SGS closures we study include the Smagorinsky formulation, a scale‐invariant dynamic model, and a scale‐dependent dynamic model. Downslope fluxes of mass and buoyancy deficit are highly sensitive to SGS closure choice. Due to strong shear and strong stratification, the dynamic models show a reduction of the Smagorinsky coefficient near the surface relative to the Smagorinsky model. Furthermore, results from both scale‐dependent dynamic models suggest that the assumptions of scale invariance in the dynamic model are violated. We present a second set of experiments which focus on grid resolution requirements of eddy‐resolving simulations of drainage flows. Downslope buoyancy and mass flux predictions produced by the scale‐dependent dynamic model are more robust with respect to grid resolution and grid anisotropy than the scale‐invariant dynamic and Smagorinsky SGS models. Predictions of vertically integrated downvalley mass and buoyancy fluxes are more sensitive to vertical grid resolution than horizontal grid resolution.
Regional Sustainability Partnerships: The Leadership Needed to Make Them Work Effectively
Authors: Milliman John , Grosskopf John
Published: June 2013

Durable partnerships require sound group processes and leadership skills
US EPA Releases Draft TSCA Chemical Risk Assessments: What Can We Infer?
Authors: Bergeson Lynn L.
Published: June 2013

Draft risk assessments provide insights into US EPA's direction
Organizations in Transition: An Updated Annotated Bibliography of Published Literature on Environmental, Health, and Safety Organizations (2004–Present)—Part 1: Intrinsic Organizational Properties
Authors: Epshtein Olga , MacLean Richard
Published: June 2013

Selected articles on the practical aspects of managing EHS/S organizations
Two ultimate tests of constrained supersymmetry
Authors: Kowalska Kamila , Roszkowski Leszek , Sessolo Enrico Maria
Published: June 2013

Abstract

We examine the prospects of using two alternative and complementary ways to explore the regions that are favored by global constraints in two simple unified supersymmetric models: the CMSSM and the NUHM. First, we consider BR (B
s → μ
+
μ
−), which has recently been for the first time measured by LHCb. In the CMSSM we show that ultimate, but realistic, improvement in the determination of the observable to about 5-10% around the Standard Model value would strongly disfavor the A-funnel region, while not affecting much the other favored regions. Second, we show that all the favored regions of the CMSSM will be, for the most part, sensitive to direct dark matter searches in future one-tonne detectors. A signal at low WIMP mass (≲ 450 GeV) and low spin-independent cross section would then strongly favor the stau coannihilation region while a signal at higher WIMP mass (~ 800 GeV to ~ 1.2 TeV) would clearly point to the region where the neutralino is higgsino-like with mass ~ 1 TeV. A nearly complete experimental testing of the CMSSM over multi-TeV ranges of superpartner masses, far beyond the reach of direct SUSY searches at the LHC, can therefore be achievable. In the NUHM, in contrast, similar favored regions exist but a sample study reveals that even a precise determination of BR (B
s → μ
+
μ
−) would have a much less constraining power on the model, including the A-funnel region. On the other hand, this could allow one to, by detecting in one-tonne detectors a signal for 500 GeV ≲ mχ ≲ 800 GeV, strongly disfavor the CMSSM.
The Transnational Alliance for Genetic Counseling: Promoting International Communication and Collaboration
Authors: Edwards Janice G.
Published: June 2013

The Transnational Alliance for Genetic Counseling seeks to promote communication and collaboration among genetic counselor educators, internationally. Connecting and building global relationships among colleagues also promotes the development of the genetic counseling profession. Genetic counselors everywhere can achieve deeper understanding of their work by seeking international perspectives.
Bilateral Ulnar Neuropathy at the Elbow Secondary to Neuropathic Arthropathy Associated With Syringomyelia
Authors: Aly Abdel‐Rahman , Rajasekaran Sathish , Obaid Haron , Bernacki Barry
Published: June 2013

Neuropathic arthropathy (NA), also known as Charcot joint, refers to a chronic progressive degenerative arthritis that is associated with an underlying central or peripheral neurologic disorder. The elbow is rarely reported to be involved in NA, but when affected, it is commonly a result of a cervical syrinx or tabes dorsalis. Few reports in the literature describe ulnar neuropathy at the elbow (UNE) associated with NA of the elbow, and none describe bilateral UNE in association with a cervicothoracic syrinx. We present a unique case of bilateral UNE resulting from NA of the elbow associated with a cervicothoracic syrinx.
Paleoclimate and growth rates of speleothems in the northwestern Iberian Peninsula over the last two glacial cycles
Authors: Stoll Heather M. , Moreno Ana , Mendez-Vicente Ana , Gonzalez-Lemos Saul , Jimenez-Sanchez Montserrat , Dominguez-Cuesta Maria Jose , Edwards R. Lawrence , Cheng Hai , Wang Xianfeng
Published: June 2013

Speleothem growth requires humid climates sufficiently warm to stimulate soil CO2 production by plants. We compile 283 U/Th dates on 21 stalagmites from six cave systems in the NW coast of Spain to evaluate if there are patterns in stalagmite growth that are evidence of climatic forcing. In the oldest stalagmites, from marine oxygen isotope stage (MIS) 7–5, growth persists through the glacial period. Hiatuses and major reductions in growth rate occur during extreme minima in summer insolation. Stalagmites active during the last interglaciation cease growth at the MIS 5–4 boundary (74 ka), when regional sea-surface temperature cooled significantly. During MIS 3, only two stalagmites grew; rates were highest between 50 and 60 ka during the maximum in summer insolation. One stalagmite grew briefly at 41 ka, 36.5 and 28.6 ka, all during warm phases of the Dansgaard–Oeschger cycles. A pronounced Holocene optimum in stalagmite growth occurs from 9 to 6 ka. The cessation of most growth by 4.1 ka, coincident with broad increases in aridity over the Mediterranean and areas influenced by the North African Monsoon, suggest that regions such as NW Spain, with dominant Atlantic moisture sources, also experienced increased aridity at this time.
Biostratigraphic significance of brachiopods near the Devonian–Carboniferous boundary
Authors: MOTTEQUIN BERNARD , BRICE DENISE , LEGRAND-BLAIN MARIE
Published: June 2013

The biostratigraphic significance of selected uppermost Famennian (Upper Devonian) and lower Tournaisian (Mississippian) brachiopod genera, belonging to the orders Rhynchonellida (e.g.Araratella), Spiriferida (e.g.Sphenospira,Prospira), Spiriferinida (Syringothyris) and Productida (except Chonetidina), is discussed. Owing to the difficulties of identifying productidine and strophalosiidine genera, in contrast to rhynchonellides and spiriferides, the biostratigraphic potential of the former has generally been overlooked. Brachiopods flourished in neritic environments that were unfavourable for conodonts and ammonoids. In the absence of the latter traditional marker fossils, they are potentially important for locating the Devonian–Carboniferous boundary in shallow water depositional settings in conjunction with rugose corals and foraminifers. On a worldwide scale, further work is required to reach a better assessment of the aftermath of the Hangenberg biological Crisis on brachiopods, notably in revising the faunas from the classical areas of the Famennian and Tournaisian stages in Western Europe.
Studentische Lehre im Fach Kinder- und Jugendpsychiatrie und -psychotherapie in Deutschland
Authors: Becker Katja , Resch Franz , Fegert Jörg M. , Häßler Frank
Published: June 2013

Einleitung: Wissen über kinder- und jugendpsychiatrische Störungen, deren Diagnostik und Therapie, Kenntnisse über Risiken devianter Entwicklungen, sowie das Erlernen von Fertigkeiten im adäquaten Umgang mit Kindern und Jugendlichen gehören in jede Medizinerausbildung. Die vorliegende Arbeit ist eine Bestandsaufnahme der Lehre im Fach Kinder- und Jugendpsychiatrie (KJP) an den medizinischen Fakultäten in Deutschland. Methodik: Es wurden alle Lehrstuhlinhaber für KJP befragt zur Einbindung in die Pflichtlehre, zu den Lehrangeboten für KJP vor Ort und zu Lehrangeboten für andere Fachbereiche. Ergebnisse: An 25 von 26 medizinischen Fakultäten mit Lehrstuhl für KJP ist das Fach KJP bereits in die Pflichtlehre für Mediziner integriert. Die Vorlesung wird entweder als eigenständige KJP-Vorlesung gehalten oder ist in die Vorlesung Psychiatrie, Pädiatrie und/oder Psychosomatik integriert. Die durchschnittlich 1.2 Semesterwochenstunden umfassende Hauptvorlesung (Range von 0.1 bis 2 SWS; entsprechend 2 bis 28 Unterrichtseinheiten KJP pro Semester) wird durch zahlreiche weitere Lehrangebote ergänzt, wie Praktika, vertiefende Veranstaltungen und Wahlpflichtfachangebote. Das KJP-Wahltertial des Praktischen Jahrs kann an allen Orten mit KJP-Lehrstuhl absolviert werden. Oft wird KJP-Lehre auch für andere Fachbereiche angeboten, am häufigsten für Studierende der Psychologie und der Pädagogik. Schlussfolgerung: Ein übergeordnetes Ziel sollte es sein, KJP aufgrund ihrer Bedeutung als Approbationsfach in der ärztlichen Ausbildungsordnung zu verankern und zukünftig an allen 35 Universitäten mit Fachbereich Medizin in Deutschland zu lehren.
Toward Improved Spectral Measures of /s/: Results From Adolescents
Authors: Koenig Laura L. , Shadle Christine H. , Preston Jonathan L. , Mooshammer Christine R.
Published: June 2013

Purpose

This article introduces theoretically driven acoustic measures of /s/ that reflect aerodynamic and articulatory conditions. The measures were evaluated by assessing whether they revealed expected changes over time and labiality effects, along with possible gender differences suggested by past work.

Method

Productions of /s/ were extracted from various speaking tasks from typically speaking adolescents (6 boys, 6 girls). Measures were made of relative spectral energies in low- (550–3000 Hz), mid- (3000–7000 Hz), and high-frequency regions (7000–11025 Hz); the mid-frequency amplitude peak; and temporal changes in these parameters. Spectral moments were also obtained to permit comparison with existing work.

Results

Spectral balance measures in low–mid and mid–high frequency bands varied over the time course of /s/, capturing the development of sibilance at mid-fricative along with showing some effects of gender and labiality. The mid-frequency spectral peak was significantly higher in nonlabial contexts, and in girls. Temporal variation in the mid-frequency peak differentiated ±labial contexts while normalizing over gender.

Conclusions

The measures showed expected patterns, supporting their validity. Comparison of these data with studies of adults suggests some developmental patterns that call for further study. The measures may also serve to differentiate some cases of typical and misarticulated /s/.
Equation of state and phase diagram of ammonia at high pressures from ab initio simulations
Authors: Bethkenhagen Mandy , French Martin , Redmer Ronald
Published: June 2013

We present an equation of state as well as a phase diagram of ammonia at high pressures and high temperatures derived from ab initio molecular dynamics simulations. The predicted phases of ammonia are characterized by analyzing diffusion coefficients and structural properties. Both the phase diagram and the subsequently computed Hugoniot curves are compared to experimental results. Furthermore, we discuss two methods that allow us to take into account nuclear quantum effects, which are of considerable importance in molecular fluids. Our data cover pressures up to 330 GPa and a temperature range from 500 K to 10 000 K. This regime is of great interest for interior models of the giant planets Uranus and Neptune, which contain, besides water and methane, significant amounts of ammonia.
Formation mechanisms of embedded nanocrystals in SiNx
Authors: Canniff J. C. , Wood A. W. , Goldman R. S.
Published: June 2013

We have investigated the formation of embedded nanocrystals (NCs) in SiNx using Ga+ focused-ion beam irradiation of SiNx membranes, followed by rapid thermal annealing (RTA). During irradiation, redeposition is enhanced by developing side walls, leading to enhanced near-surface [Ga] and [Si]. Subsequent RTA leads to the formation of Si and Ga NCs embedded in SiNx. When the ratio of the irradiated area to the sidewall area is increased, redeposition is limited, and SiNx and GaN NCs are also apparent. We discuss the effect of limited redeposition on NC formation and the catalytic effect of Ga on Si NC nucleation and growth.
Note: Optical optimization for ultrasensitive photon mapping with submolecular resolution by scanning tunneling microscope induced luminescence
Authors: Chen L. G. , Zhang C. , Zhang R. , Zhang X. L. , Dong Z. C.
Published: June 2013

We report the development of a custom scanning tunneling microscope equipped with photon collection and detection systems. The optical optimization includes the comprehensive design of aspherical lens for light collimation and condensing, the sophisticated piezo stages for in situ lens adjustment inside ultrahigh vacuum, and the fiber-free coupling of collected photons directly onto the ultrasensitive single-photon detectors. We also demonstrate submolecular photon mapping for the molecular islands of porphyrin on Ag(111) under small tunneling currents down to 10 pA and short exposure time down to 1.2 ms/pixel. A high quantum efficiency up to 10−2 was also observed.
Lightcone dualities for curves in the lightcone unit 3-sphere
Authors: Izumiya Shyuichi , Jiang Yang , Sato Takami
Published: June 2013

In this paper, we consider the curves in the unit 3-sphere in the lightcone. The unit 3-sphere can be canonically embedded in the lightcone and de Sitter 4-space in Lorentz-Minkowski 5-space. We investigate these curves in the framework of the theory of Legendrian dualities between pseudo-spheres in Lorentz-Minkowski 5-space.
The effect of solute segregation on strain localization in nanocrystalline thin films: Dislocation glide vs. grain-boundary mediated plasticity
Authors: Lohmiller Jochen , Kobler Aaron , Spolenak Ralph , Gruber Patric A.
Published: June 2013

Deformation mechanisms of nanocrystalline Au and AuCu thin films on compliant substrates were investigated by synchrotron-based in situ tensile testing and Automated Crystal Orientation Mapping using transmission electron microscopy. The results demonstrate that intragranular dislocation plasticity, inferred from evolution of deformation texture, is responsible for the formation of periodic and ordered shear bands in AuCu films. In contrast, pure Au films deform homogeneously without shear band formation and without evolution of deformation texture. Cu solutes are deemed to pin grain boundaries thereby enforce dislocation glide, while in pure Au, plasticity is carried by grain boundary shear and grain boundary migration.
Practicable alleviation of efficiency droop effect using surface plasmon coupling in GaN-based light emitting diodes
Authors: Yang Wei , He Yongfa , Liu Lei , Hu Xiaodong
Published: June 2013

We studied the practicable alleviation of efficiency droop effect in GaN-based light emitting diodes (LEDs) with surface plasmon (SP) coupling. Our approach is based on a simple ABC model which is extended by a Purcell factor that relates the SP coupling rate to the radiative recombination rate based on Fermi's golden rule. Purcell factors as small as two are found to be sufficient to obtain a low efficiency droop of only 5.2% at a current density of 200 A/cm2. It is shown that a high probability of photon extraction from the SP modes is required for enhanced light output power. SP coupling is more beneficial to improve LED performance within the “green-yellow gap” suffering from low luminescence efficiency (less than 20%).
Spin filter effect at room temperature in GaN/GaMnN ferromagnetic resonant tunnelling diode
Authors: Wójcik P. , Adamowski J. , Wołoszyn M. , Spisak B. J.
Published: June 2013

We have investigated the spin current polarization without the external magnetic field in the resonant tunneling diode with the emitter and quantum well layers made from the ferromagnetic GaMnN. For this purpose, we have applied the self-consistent Wigner-Poisson method and studied the spin-polarizing effect for the parallel and antiparallel alignments of the magnetization of the ferromagnetic layers. The results of our calculations show that the antiparallel magnetization is much more advantageous for the spin filter operation and leads to the full spin current polarization at low temperatures and 35% spin polarization of the current at room temperature.
Graphene metamaterial for optical reflection modulation
Authors: Zhu Weiren , Rukhlenko Ivan D. , Premaratne Malin
Published: June 2013

We theoretically demonstrate an advanced optical modulator based on graphene-enabled metamaterial with voltage-controllable reflectance. A significant modulation depth of the reflection coefficient is achieved through a voltage biasing of the graphene's Fermi level, leading to an almost instantaneous change in the effective permittivity of the graphene. We show that even a single graphene layer integrated into the structure of a simple metamaterial absorber enables a relative change in the reflectance as high as 361% at near-infrared frequencies. The designed modulator may be used in optical communication systems and biomedical sensing apparatus.
Dispersal and home-range dynamics of exotic, male sika deer in Maryland
Authors: Kalb David M. , Bowman Jacob L. , Eyler T. Brian
Published: June 2013

Content
An unknown number (n = four or five) and sex of sika deer (Cervus nippon yakushimae) were introduced to the Delmarva Peninsula, Maryland, in 1916. Since introduction, their population has grown exponentially.

Aims
The purpose of our study was to investigate dispersal and home-range size to enable better management of this exotic species in the presence of native white-tailed deer (Odocoileus virginianus).

Methods
We collected telemetry locations on 60 males (captured during their first winter) from 2008 to 2010. Animals were classified into three movement groups, including local, migratory and nomadic post-dispersal.

Key results
Average home-range sizes ranged from 464 to 4121 ha and were influenced by season and deer movement grouping (P = 0.0001). Of 20 deer that dispersed, 19 did so at 1 year of age. Dispersal distance and direction were random across the landscape (P = 0.899). Local deer were the most common movement group (70%; 42 of 60) and were characterised by short movements confined to a well established home range. We observed 14 deer migrations, characterised by round-trip movements associated with seasons and directionality (P = 0.003). Four deer were classified as nomadic and had long-distance movements across the landscape unassociated with seasons.

Conclusions
To aid managers in controlling the expansion of the population, we provide data regarding the manner, distance and direction that sika deer move. Our results show that sika deer have variable movement strategies and large home ranges.

Implications
Variation in movement types will influence spread of the population, confounding species interactions, management and harvest strategies. The present results may have implications to other areas that also have sika populations.
Fitness landscape for nucleosome positioning
Authors: Weghorn Donate , Lässig Michael
Published: June 2013

Histone–DNA complexes, so-called nucleosomes, are the building blocks of DNA packaging in eukaryotic cells. The histone-binding affinity of a local DNA segment depends on its elastic properties and determines its accessibility within the nucleus, which plays an important role in the regulation of gene expression. Here, we derive a fitness landscape for intergenic DNA segments in yeast as a function of two molecular phenotypes: their elasticity-dependent histone affinity and their coverage with transcription factor binding sites. This landscape reveals substantial selection against nucleosome formation over a wide range of both phenotypes. We use it as the core component of a quantitative evolutionary model for intergenic DNA segments. This model consistently predicts the observed diversity of histone affinities within wild
Saccharomyces paradoxus
populations, as well as the affinity divergence between neighboring
Saccharomyces
species. Our analysis establishes histone binding and transcription factor binding as two separable modes of sequence evolution, each of which is a direct target of natural selection.
Protein tyrosine phosphatase
UBASH3B
is overexpressed in triple-negative breast cancer and promotes invasion and metastasis
Authors: Lee Shuet Theng , Feng Min , Wei Yong , Li Zhimei , Qiao Yuanyuan , Guan Peiyong , Jiang Xia , Wong Chew Hooi , Huynh Kelly , Wang Jinhua , Li Juntao , Karuturi K. Murthy , Tan Ern Yu , Hoon Dave S. B. , Kang Yibin , Yu Qiang
Published: June 2013

Efforts to improve the clinical outcome of highly aggressive triple-negative breast cancer (TNBC) have been hindered by the lack of effective targeted therapies. Thus, it is important to identify the specific gene targets/pathways driving the invasive phenotype to develop more effective therapeutics. Here we show that ubiquitin-associated and SH3 domain-containing B (UBASH3B), a protein tyrosine phosphatase, is overexpressed in TNBC, where it supports malignant growth, invasion, and metastasis largely through modulating epidermal growth factor receptor (EGFR). We also show that
UBASH3B
is a functional target of anti-invasive microRNA
200a
(
miR200a
) that is down-regulated in TNBC. Importantly, the oncogenic potential of
UBASH3B
is dependent on its tyrosine phosphatase activity, which targets CBL ubiquitin ligase for dephosphorylation and inactivation, leading to EGFR up-regulation. Thus,
UBASH3B
may function as a crucial node in bridging multiple invasion-promoting pathways, thereby providing a potential therapeutic target for TNBC.
Human interactome resource and gene set linkage analysis for the functional interpretation of biologically meaningful gene sets
Authors: Zhou Xi , Chen Pengcheng , Wei Qiang , Shen Xueling , Chen Xin
Published: June 2013

Motivation: A molecular interaction network can be viewed as a network in which genes with related functions are connected. Therefore, at a systems level, connections between individual genes in a molecular interaction network can be used to infer the collective functional linkages between biologically meaningful gene sets.

Results: We present the human interactome resource and the gene set linkage analysis (GSLA) tool for the functional interpretation of biologically meaningful gene sets observed in experiments. GSLA determines whether an observed gene set has significant functional linkages to established biological processes. When an observed gene set is not enriched by known biological processes, traditional enrichment-based interpretation methods cannot produce functional insights, but GSLA can still evaluate whether those genes work in concert to regulate specific biological processes, thereby suggesting the functional implications of the observed gene set. The quality of human interactome resource and the utility of GSLA are illustrated with multiple assessments.

Availability:  http://www.cls.zju.edu.cn/hir/

Contact:  xinchen@zju.edu.cn

Supplementary information:  Supplementary data are available at Bioinformatics online.
Charge asymmetry in the proteins of the outer membrane
Authors: Slusky Joanna S. G. , Dunbrack Roland L.
Published: June 2013

Motivation: Outer membrane beta-barrels (OMBBs) are the proteins found in the outer membrane of bacteria, mitochondria and chloroplasts. There are thousands of beta-barrels reported in genomic databases with ∼2–3% of the genes in gram-negative bacteria encoding these proteins. These proteins have a wide variety of biological functions including active and passive transport, cell adhesion, catalysis and structural anchoring. Of the non-redundant OMBB structures in the Protein Data Bank, half have been solved during the past 5 years. This influx of information provides new opportunities for understanding the chemistry of these proteins. The distribution of charges in proteins in the outer membrane has implications for how the mechanism of outer membrane protein insertion is understood. Understanding the distribution of charges might also assist in organism selection for the heterologous expression of mitochondrial OMBBs.

Results: We find a strong asymmetry in the charge distribution of these proteins. For the outward-facing residues of the beta-barrel within regions of similar amino acid density for both membrane leaflets, the external side of the outer membrane contains almost three times the number of charged residues as the internal side of the outer membrane. Moreover, the lipid bilayer of the outer membrane is asymmetric, and the overall preference for amino acid types to be in the external leaflet of the membrane correlates roughly with the hydrophobicity of the membrane lipids. This preference is demonstrably related to the difference in lipid composition of the external and internal leaflets of the membrane.

Contact: joanna.slusky@fccc.edu

Supplementary information:  Supplementary data are available at Bioinformatics online.
The influence of product features on brand switching: the case of magnetic resonance imaging equipment
Authors: Al‐Kwifi Sam O. , McNaughton Rod B.
Published: June 2013

Purpose

This paper seeks to provide evidence that the long‐term success of capital‐intensive technology products requires continuous integration of innovations in the form of new features and capabilities that meet broad user preferences.

Design/methodology/approach

Magnetic resonance imaging (MRI) research centers, which represent lead users in this industry, are used as a case study. An online survey was developed to identify and rank the main factors behind brand switching, then secondary sources are used to confirm the research results.

Findings

A multi‐faceted approach to data collection is used to show that product innovations in the form of specific features are the main motive for switching to a new technology, consistent with the expectation that lead users seek technologies that maintain leading‐edge positions.

Research limitations/implications

There are limitations to generalizing from this case study to other industries. The findings can be generalized to industries with similar characteristics, such as aircraft and heavy machinery manufacturing. In practice, managers should find a reliable strategy to assess factors underpinning brand switching that is unique to their industry. Determining the main factors behind switching is a critical matter when defining the appropriate strategy to keep their market share from eroding.

Originality/value

The literature reports considerable research that investigates brand switching. However, most of it focuses on highly competitive markets for consumer goods. This paper addresses a paucity of knowledge about what influences lead users of capital‐intensive products to switch between brands.
Portfolio district reform meets school turnaround
Authors: Marsh Julie A. , Strunk Katharine O. , Bush Susan
Published: June 2013

Purpose

Despite the popularity of school “turnaround” and “portfolio district” management as solutions to low performance, there has been limited research on these strategies. The purpose of this paper is to address this gap by exploring the strategic case of Los Angeles Unified School District's Public School Choice Initiative (PSCI) which combined both of these reforms. It examines how core mechanisms of change played out in schools and communities during the first two years of implementation.

Design/methodology/approach

The paper draws on a mixed methods study, combining data from surveys, case studies, leader interviews, observations, and document review. It is guided by a conceptual framework grounded in research on school turnaround and portfolio districts, along with the district's implicit theory of change.

Findings

The paper finds early success in attracting diverse stakeholder participation, supporting plan development, and ensuring transparency. However, data also indicate difficulty establishing understanding and buy‐in, engaging parents and community, attracting sufficient supply of applicants, maintaining neutrality and the perception of fairness, and avoiding unintended consequences of competition – all of which weakened key mechanisms of change.

Research limitations/implications

Data from parent focus groups and school sites may not be representative of the entire population of parents and schools, and data come from a short period of time.

Practical implications

The paper finds that developing processes and procedures to support complex reform takes time and identifies roadblocks others may face when implementing school turnaround and portfolio management. The research suggests districts invest in ways to ensure neutrality and create a level playing field. It also indicates that leaders should anticipate challenges to engaging parents and community members, such as language and literacy barriers, and invest in the development of unbiased, high‐quality information and opportunities that include sufficient time and support to ensure understanding.

Originality/value

This paper begins to fill a gap in research on popular reform strategies for improving low‐performing schools.
New York City's Children First Networks: turning accountability on its head
Authors: Wohlstetter Priscilla , Smith Joanna , Gallagher Andrew
Published: June 2013

Purpose

The purpose of this paper is to report findings from an exploratory study of New York's Children First Networks (CFNs); to examine what is known about the CFNs thus far, drawing on new empirical research, as well as document review and analysis of secondary sources.

Design/methodology/approach

Organizational learning theory guided this qualitative study. As such, in‐depth interviews conducted with central office staff, network leadership teams, cluster leaders, and principals focused on the flow and management of information within the networks; the ways in which stakeholders developed shared meanings; how collective intelligence was built and transmitted; and organizational responses to the early experience of the CFNs.

Findings

Findings highlight the tools and processes the NYC Department of Education (DOE) has put into place to operationalize the CFNs. Respondents identified as critical the replacement of supervisory leadership from the district with customization of services provided by the network teams to promote principal‐led reforms. Increased efficiency was noted by interviewees, but a number of challenges in the reform’s implementation also surfaced that point to the limitations of the CFNs as a capacity‐building mechanism.

Research limitations/implications

As an exploratory study, this research is intended to inform larger‐scale, mixed‐methods investigations of school networks, especially those implementing reforms aimed at improving teaching and learning in schools. Research is needed into the resource exchanges between individuals and groups in networks, what differentiates high‐performing from lower‐performing networks, and how data are used to inform the evolution of network structures and practices.

Originality/value

This study is the first peer‐reviewed article on the evolution of New York City's Children First Networks.
Factors influencing consumer behaviour towards store brands: evidence from the French market
Authors: Fall Diallo Mbaye , Chandon Jean‐Louis , Cliquet Gérard , Philippe Jean
Published: June 2013

Purpose

This paper aims to investigate how consumer and image factors as well as store familiarity influence store brand (SB) purchase behaviour. SBs are now widely offered by European mass retailers. However, consumer behaviour toward SBs is not yet clearly understood in all European markets.

Design/methodology/approach

The authors analysed data collected from 266 respondents and used structural equation modelling to test the main hypotheses. They then carried out ANOVA and MANOVA analyses to test the effect of store familiarity on SB purchase behaviour.

Findings

Results indicate that store image perceptions, SB price‐image, value consciousness, and SB attitude have significant and positive influence on SB purchase behaviour. Store familiarity positively influences SB choice, but not SB purchase intention. None of the socio‐demographic variables (age, gender, household income, and family size) included as control variables have an effect on SB choice.

Research limitations/implications

The study is limited because it did not account for the effect of product categories on SB purchase behaviour. Consequently, results cannot be determined for different product categories. It would also be appropriate to measure SB choice in a more concrete way, such as using scanner data.

Practical implications

Findings highlight the importance of value consciousness, store image perceptions, and SB price‐image on SB purchase behaviour. They also show greater popularity of SB products among consumers, including those with high household income.

Originality/value

There is increased value to retailers in studying how consumer and image factors jointly influence SB purchase behaviour, whilst also accounting for store familiarity instead of brand familiarity.
Utilising product knowledge
Authors: McGuinness Donna , Hutchinson Karise
Published: June 2013

Purpose

The purpose of this paper is to demonstrate how product knowledge is utilised by specialist independent grocery retailers (SIGRs) and how it can enhance competitive advantage for these firms.

Design/methodology/approach

A case study approach was deemed most appropriate to gain insight into an unexplored area of study. A total of 30 in‐depth interviews were conducted over a six‐month period supported by the collection of observation data and documentation. A purposive sampling method was adopted and the owner managers of the chosen retailers were interviewed as key informants for the study.

Findings

It was found that four main resources created the concept product strategy and ultimately explained the success of SIGRs. These relate to knowledge of how to provide a unique product; knowledge of identifying and sourcing from quality suppliers; knowledge of recipes, preparation and storage methods; and knowledge of how to merchandise products.

Practical implications

It is argued that if these specialist grocery firms can achieve sustained competitive advantage from building and exploiting product knowledge, so too can other independent retailers in the sector.

Originality/value

This paper provides empirical evidence and theoretical understanding of product knowledge as a competitive advantage for SIGRs, which is a neglected area of study in the retail literature.