bluuebunny/crossref_metadata_2025 huggingface dataset:
Ti6Al4V coating for carbon/carbon composites synthesized by magnetron sputtering: microstructure and in‐vitro biotests
Authors: Zhang Lei‐Lei , Li He‐Jun , Lu Jin‐Hua , Zhang Yu‐Lei , Cao Sheng , Zhao Xue‐Ni , He Zi‐Bo
Published: December 2012

In order to improve the cell compatibility of biomedical carbon/carbon composites, Ti6Al4V coatings were applied on carbon/carbon composites by magnetron sputtering technique. The microstructure and cell responses of the coatings were evaluated, and the bonding strength between the coatings and carbon/carbon composites was analyzed. The Ti6Al4V coatings modulated the surface morphology, decreased the surface roughness, improved the surface wettability and achieved a strong bonding strength to carbon/carbon composites. The cells showed larger cell extension and higher cell proliferation for the Ti6Al4V coatings than for the carbon/carbon composites. Copyright © 2012 John Wiley & Sons, Ltd.
The performance of different propensity score methods for estimating marginal hazard ratios
Authors: Austin Peter C.
Published: December 2012

Propensity score methods are increasingly being used to reduce or minimize the effects of confounding when estimating the effects of treatments, exposures, or interventions when using observational or non‐randomized data. Under the assumption of no unmeasured confounders, previous research has shown that propensity score methods allow for unbiased estimation of linear treatment effects (e.g., differences in means or proportions). However, in biomedical research, time‐to‐event outcomes occur frequently. There is a paucity of research into the performance of different propensity score methods for estimating the effect of treatment on time‐to‐event outcomes. Furthermore, propensity score methods allow for the estimation of marginal or population‐average treatment effects. We conducted an extensive series of Monte Carlo simulations to examine the performance of propensity score matching (1:1 greedy nearest‐neighbor matching within propensity score calipers), stratification on the propensity score, inverse probability of treatment weighting (IPTW) using the propensity score, and covariate adjustment using the propensity score to estimate marginal hazard ratios. We found that both propensity score matching and IPTW using the propensity score allow for the estimation of marginal hazard ratios with minimal bias. Of these two approaches, IPTW using the propensity score resulted in estimates with lower mean squared error when estimating the effect of treatment in the treated. Stratification on the propensity score and covariate adjustment using the propensity score result in biased estimation of both marginal and conditional hazard ratios. Applied researchers are encouraged to use propensity score matching and IPTW using the propensity score when estimating the relative effect of treatment on time‐to‐event outcomes. Copyright © 2012 John Wiley & Sons, Ltd.
Single Quantum Dot Analysis Enables Multiplexed Point Mutation Detection by Gap Ligase Chain Reaction
Authors: Song Yunke , Zhang Yi , Wang Tza‐Huei
Published: December 2012

Gene point mutations present important biomarkers for genetic diseases. However, existing point mutation detection methods suffer from low sensitivity, specificity, and a tedious assay processes. In this report, an assay technology is proposed which combines the outstanding specificity of gap ligase chain reaction (Gap‐LCR), the high sensitivity of single‐molecule coincidence detection, and the superior optical properties of quantum dots (QDs) for multiplexed detection of point mutations in genomic DNA. Mutant‐specific ligation products are generated by Gap‐LCR and subsequently captured by QDs to form DNA–QD nanocomplexes that are detected by single‐molecule spectroscopy (SMS) through multi‐color fluorescence burst coincidence analysis, allowing for multiplexed mutation detection in a separation‐free format. The proposed assay is capable of detecting zeptomoles of KRAS codon 12 mutation variants with near 100% specificity. Its high sensitivity allows direct detection of KRAS mutation in crude genomic DNA without PCR pre‐amplification.
A new approach to authenticating and encrypting Voice over Internet Protocol communications
Authors: Lago‐Fernández J. , Gil‐Castiñeira F. , González‐Castaño F.J. , Román‐Portabales A.
Published: December 2012

Traditionally, call authentication and security have not raised user concerns because wiretapping requires physical access to the phone line and special equipment. However, Voice over Internet Protocol (VoIP) communications are becoming increasingly popular, and there is the perception that they may be easier to intercept or impersonate (thus creating higher demand for security solutions), especially if the connection occurs over wireless links. The Session Initiation Protocol is widely used for managing voice and video communications over the Internet, and the Real‐time Transport Protocol is used to carry voice and/or video streams. Session Initiation Protocol, however, was not designed with security in mind and is vulnerable to attacks.

Furthermore, there are cases in which it is necessary to authenticate the call participants (e.g., when they are asked to disclose confidential information). There are few practical solutions to this problem, essentially because they require complex infrastructures to manage keys and certificates.

In this paper, we solve this problem with a novel approach: the use of national public key infrastructures in combination with national Electronic Identity smart cards, created by governments to execute trusted electronic transactions and establish trusted identities. In addition, we will show how our approach enables new use cases (e.g., institutions – hospitals, banks, government, etc. – can be confident that they exchange confidential information to the intended person and vice versa) and simplifies the steps necessary to secure and authenticate a VoIP communication with ZRTP, simplifying and therefore encouraging the use of secure VoIP communications between authenticated users. Copyright © 2012 John Wiley & Sons, Ltd.
“Just a Typical Teenager”: The Social Ecology of “Normal Adolescence”—Insights from Diabetes Care
Authors: Allen Davina
Published: December 2012

In Western society “normal adolescence” is understood to be a biologically driven phase characterized by emotional turmoil and irrational behavior. Despite being discredited within academic literature this discourse persists both in formal theory and everyday use. Drawing on the case of diabetes care, I argue that the discourse of “normal adolescence” derives its power from its value as a vocabulary of motive through which to navigate the contradictions inherent in the social order at this stage of the life‐course. While helping us to comprehend sociologically the ecological niche in which “normal adolescence” is sustained, this analysis raises questions about the persistence of this discourse for social action.
Simulation on locating Partial Discharge source occurring on distribution line by estimating the DOA of emitted EM waves
Authors: Tian Ye , Kawada Masatake
Published: December 2012

A new method for locating the position of partial discharge (PD), which occurs on distribution line, is presented. The method uses the direction‐of‐arrival (DOA) of electromagnetic (EM) waves emitted from PD source. The DOAs of EM waves in azimuth and elevation angles are estimated by using the two‐dimensional improved coherent signal subspace method (2D I‐CSM). The position of PD can be located as the intersection of DOAs estimated at two points. In this paper, the finite difference time domain (FDTD) method is applied to simulate the propagation of EM waves emitted from PD, which occurs on distribution line. The proposed method is applied to locate the position of PD based on the simulation results. The method is shown to be useful for locating the position of PD in multipath environment. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
The crude extract of Corni Fructus induces apoptotic cell death through reactive oxygen species‐modulated pathways in U‐2 OS human osteosarcoma cells
Authors: Liao Ching‐Lung , Hsu Shu‐Chun , Yu Chien‐Chih , Yang Jai‐Sing , Tang Nou‐Ying , Wood Wellington Gibson , Lin Jaung‐Geng , Chung Jing‐Gung
Published: December 2012

Crude extract of Corni Fructus (CECF) has been used in Traditional Chinese medicine for the treatment of different diseases for hundreds of years. The purpose of this study was to investigate the cytotoxic effects of CECF on U‐2 OS human osteosarcoma cells. Flow cytometry was used for measuring the percentage of viable cells, cell‐cycle distribution, apoptotic cells in sub‐G1 phase, reactive oxygen species (ROS), Ca2+ levels, and mitochondrial membrane potential (ΔΨm). Comet assay and 4′‐6‐diamidino‐2‐phenylindole staining were used for examining DNA damage and condensation. Western blotting was used to examine apoptosis‐associated protein levels in U‐2 OS cells after exposed to CECF. Immunostaining and confocal laser system microscope were used to examine protein translocation after CECF incubation. CECF decreased the percentage of viability, induced DNA damage and DNA condensation, G0/G1 arrest, and apoptosis in U‐2 OS cells. CECF‐stimulated activities of caspase‐8, caspase‐9, and caspase‐3, ROS, and Ca2+ production, decreased ΔΨm levels of in U‐2 OS cells. CECF increased protein levels of caspase‐3, caspase‐9, Bax, cytochrome c, GRP78, AIF, ATF‐6α, Fas, TRAIL, p21, p27, and p16 which were associated with cell‐cycle arrest and apoptosis. These findings suggest that CECF triggers apoptosis in U‐2 OS cells via ROS‐modulated caspase‐dependent and ‐independent pathways. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 1020–1031, 2014.
Hydrated Rare Earth Structural Networks containing the Phenylene‐1, 2‐dioxydiacetate (PDDA) Ligand
Authors: Behrsing Thomas , Deacon Glen B. , Junk Peter C. , Skelton Brian W. , Sobolev Alexandre N. , White Allan H.
Published: December 2012

Reaction of LnCl3 with Na2(PDDA) (PDDA = phenylene‐1, 2‐dioxydiacetate) in a 1 to 2 mol ratio in aqueous solution yielded [Ln2(PDDA)3(H2O)6]·2H2O, structurally characterized for Ln = Ce (1), Sm (2) (redetermination), Tb (3) and Y (4) in a monoclinic C2/c array, a second related structural form [orthorhombic, Pbcn] being obtained for Tb (5), Ho (6) and Er (7). The ‘domains of existence' of these two previously described forms are now extended to Ce–Dy, Y, and Eu–Er, respectively. Reaction under the same conditions for the heavier Yb3+ ion yielded [Yb2(PDDA)3(H2O)6](∞|∞)·4H2O (8), orthorhombic, Pbca. In the case of Ln = La the bimetallic species [NaLa(PDDA)2(H2O)2](∞|∞)·4H2O (9) was obtained, while reaction of LnCl3 with Na2(PDDA) in a 1 to 3 mol ratio led to the isolation of the isotypic (monoclinic, P21/c) [NaLn(PDDA)2(H2O)2](∞|∞)·4H2O) for Ln = Ce (10) and Sm (12). With the smaller Ln = Yb, the more definitively bimetallic [NaYb(PDDA)2(H2O)2](∞|∞)·3H2O (13) (triclinic, P$\bar{1}$)) was obtained, the trihydrate solvation ascribed differing from that recorded (dihydrate) in a cosynchronous report.
Energetics and life‐history of bats in comparison to small mammals
Authors: Becker N. I. , Encarnação J. A. , Tschapka M. , Kalko E. K. V.
Published: December 2012

Mammals can be aligned along a slow‐fast life‐history continuum and a low–high metabolic rate continuum based on their traits. Small non‐volant mammals occupy the fast/high end in both continua with high reproductive rates and short life spans linked with high mass‐specific metabolic rates. Bats occupy the high end of the metabolic continuum, but the slow end of the life‐history continuum with low reproductive rates and long life spans. Typically, both continua are linked, and similar life‐history traits of species are reflected in more similar metabolic rates. We therefore hypothesized that metabolic rates are similar in species with similar life‐history traits. Resting metabolic rates (RMR) were measured for three ecologically and morphologically similar sympatric bat species (Myotis nattereri,M. bechsteinii, andPlecotus auritus; Vespertilionidae) and compared to data from other similar‐sized, temperate insectivorous mammals with other life‐history strategies. The bat species share similar life‐histories and RMRs, both of which differ from the remaining mammals and therefore supporting our hypothesis. To verify that bats are similar in RMR, two energetically contrasting periods were compared. RMRs in post‐lactating females did not differ between bat species. It was, however, positively correlated with parasite load in bothMyotisspecies. However, RMRs differed during energy‐demanding pregnancy whereM. nattererihad the significantly lowest RMR, suggesting metabolic compensation as an energy‐saving strategy. We conclude that the energy requirements of bat species with similar life‐history traits resemble each other during periods of low energetic demands and are more similar to each other than to other small temperate mammals.
Induced pluripotent stem cells in reproductive medicine
Authors: Teramura Takeshi , Frampton John
Published: December 2012

Despite recent advances in reproductive medicine, there are still no effective treatments for severe infertility caused by congenital absence of germ cells or gonadotoxic treatments during prepubertal childhood. However, the development of technologies for germ cell formation from stem cells in vitro, induction of pluripotency from somatic cells, and production of patient‐specific pluripotent stem cells may provide new solutions for treating these severe fertility problems. It may be possible to produce germ cells in vitro from our own somatic cells that can be used to restore fertility. In addition, these technologies may also bring about novel therapies by helping to elucidate the mechanisms of human germ cell development. In this review, we describe the current approaches for obtaining germ cells from pluripotent stem cells, and provide basic information about induction of pluripotency and germ cell development.
Comparative functional analysis of CYP71AV1 natural variants reveals an important residue for the successive oxidation of amorpha‐4,11‐diene
Authors: Komori Aya , Suzuki Munenori , Seki Hikaru , Nishizawa Tomoko , Meyer Jacobus Johannes Marion , Shimizu Hideaki , Yokoyama Shigeyuki , Muranaka Toshiya
Published: December 2012

Artemisinin is an antimalarial sesquiterpenoid isolated from the aerial parts of the plant Artemisia annua. CYP71AV1, a cytochrome P450 monooxygenase was identified in the artemisinin biosynthetic pathway. CYP71AV1 catalyzes three successive oxidation steps at the C12 position of amorpha‐4,11‐diene to produce artemisinic acid. In this study, we isolated putative CYP71AV1 orthologs in different species of Artemisia. Comparative functional analysis of CYP71AV1 and its putative orthologs, together with homology modeling, enabled us to identify an amino acid residue (Ser479) critical for the second oxidation reaction catalyzed by CYP71AV1. Our results clearly show that a comparative study of natural variants is useful to investigate the structure–function relationships of CYP71AV1.
Biological features of core networks that result from a high-fat diet in hepatic and pulmonary tissues in mammary tumour-bearing, obesity-resistant mice
Authors: Kim Eun Ji , Oh Hea Young , Heo Hyoung-Sam , Hong Ji Eun , Jung Sung-Jae , Lee Ki Won , Park Jong Hoon , Hur Cheol-Goo , Park Jung Han Yoon
Published: December 2012

We previously demonstrated that the chronic consumption of a high-fat diet (HFD) promotes lung and liver metastases of 4T1 mammary carcinoma cells in obesity-resistant BALB/c mice. To examine early transcriptional responses to tumour progression in the liver and lungs of HFD-fed mice, 4-week-old female BALB/c mice were divided into four groups: sham-injected, control diet (CD)-fed; sham-injected, HFD-fed (SH); 4T1 cell-injected, CD-fed (TC); 4T1 cell-injected, HFD-fed (TH). Following 16 weeks of either a CD or HFD, 4T1 cells were injected into the mammary fat pads of mice in the TC and TH groups and all mice were continuously fed identical diets. At 14 d post-injection, RNA was isolated from hepatic and pulmonary tissues for microarray analysis of mRNA expression. Functional annotation and core network analyses were conducted for the TH/SH Unique gene set. Inflammation in hepatic tissues and cell mitosis in pulmonary tissues were the most significant biological functions in the TH/SH Unique gene set. The biological core networks of the hepatic TH/SH Unique gene set were characterised as those genes involved in the activation of acute inflammatory responses (Orm1, Lbp, Hp and Cfb), disordered lipid metabolism and deregulated cell cycle progression. Networks of the pulmonary Unique gene set displayed the deregulation of cell cycle progression (Cdc20, Cdk1 and Bub1b). These HFD-influenced alterations may have led to favourable conditions for the formation of both pro-inflammatory and pro-mitotic microenvironments in the target organs that promote immune cell infiltration and differentiation, as well as the infiltration and proliferation of metastatic tumour cells.
Leader Survival and Natural Disasters
Authors: Quiroz Flores Alejandro , Smith Alastair
Published: December 2012

Analyses of the occurrence of natural disasters show that in large coalition systems, such as democracies, their occurrence has little effect on protest or leader survival. However, if large numbers of people die in these disasters, more protests occur and leader survival diminishes. In contrast, for leaders in small coalition systems, the occurrence of disasters increases protests and reduces tenure, but the level of fatalities has little effect. The anticipation of these potential political effects accounts for why many more people die in disasters in small coalition systems than in large coalition systems.
A whole-of-population study of the prevalence and patterns of criminal offending in people with schizophrenia and other mental illness
Authors: Morgan V. A. , Morgan F. , Valuri G. , Ferrante A. , Castle D. , Jablensky A.
Published: December 2012

Background

Large epidemiological studies are needed to better understand the prevalence and profile of offending by people with mental illness. This study used a whole-of-population design to examine the prevalence, type and pattern of offending across all psychiatric diagnoses, including schizophrenia, compared to the general population.

Method

We used whole-of-population longitudinal record-linked data for a cohort of all Western Australians born 1955–1969 to determine arrest history over the period 1985–1996 and to ascertain recorded history of psychiatric illness. Of the cohort, 116 656 had been arrested and 40 478 were on the psychiatric case register.

Results

The period prevalence of arrest for people with any psychiatric illness was 32.1%. The highest arrest prevalence, by diagnostic category, was for substance use disorders (59.4%); the prevalence for schizophrenia was 38.7%. Co-morbid substance use disorders significantly increased risk of arrest in people with schizophrenia. The prevalence of mental illness among offenders was 11.1%: 6.5% of offenders had substance use disorders and 1.7% had schizophrenia. For the majority of offenders with a psychiatric illness, first arrest preceded first contact with mental health services; for schizophrenia only, this proportion was increasing over time. The mean percentage annual change in the number of arrests during 1985–1996 rose significantly for offenders with a psychiatric illness other than schizophrenia and dropped significantly for those with no mental illness. Compared to non-psychiatric offenders, offenders with schizophrenia were more likely to offend alone, to offend in open places and to target strangers.

Conclusions

Our findings open the way to an informed approach to the management of offenders with mental illness.
Perceptions de l’arrêt de la dialyse et des traitements de maintien de la vie chez la clientèle québécoise en hémodialyse hospitalière: comparaison selon l’âge
Authors: Gagnon Judith , Saint-Arnaud Jocelyne , Bourdeau Marc , Côté Josée , Chapados Claire , Michaud Cécile
Published: December 2012

The End-Stage Renal Disease population is aging. Considering that hemodialysis is a treatment that maintains and prolongs life, this descriptive-comparative study looks at the perceptions of patients according to age group -<65 years, n=121 and ≥65 years, n=123, as it pertains to dialysis treatment cessation and life-sustaining treatments. Results: Older patients are more indecisive as to what dialysis treatment cessation may actually represent for them (p=0,01). They expressed a greater need for support from the health care team if they decided to stop dialysis treatments (p=0,02); a greater involvement from the physician (p=0,04); and, in the event patients could not take part in end-of-life decision-making, they would give priority to the wishes of loved ones instead of their own wishes (p=0,01). Conclusion: Advanced care planning is necessary to demystify hemodialysis withdrawal and to support patients and their loved ones through this process.
General Synod of the Scottish Episcopal Church
Authors: Guild Ivor
Published: December 2012

To a Synod with little controversial on the agenda apart from the decision about the Anglican Covenant, the Primus in his charge at the opening Eucharist spoke of the economic wilderness through which society and the Church were travelling. The Covenant had been a response to the apparent wilderness of disagreement and disorder in the Anglican Communion, and he hoped that the Synod would express its deep commitment to the version of the Communion in which members were drawn closer to one another. The Scottish Church aspired to be fully engaged in society.
Validierung des Instruments zur stressbezogenen Arbeitsanalyse für Klinikärztinnen und -ärzte (ISAK)
Authors: Keller Monika , Bamberg Eva , Kersten Maren , Nienhaus Albert
Published: December 2012

Die Arbeitsbedingungen von Klinikärztinnen und -ärzten sind häufig mit Stressoren verbunden, die sich in gesundheitlichen Beeinträchtigungen sowie sinkender Qualität der Patientenversorgung auswirken können. Um Kliniken bei der Verbesserung der ärztlichen Arbeitsbedingungen zu unterstützen, wurde ein Instrument zur stressbezogenen Arbeitsanalyse für Klinikärztinnen und -ärzte entwickelt. Es erfasst die spezifischen Stressoren und Ressourcen dieser Zielgruppe und liegt in Form eines Fragebogens vor. Anhand einer Stichprobe mit N=571 Klinikärztinnen und -ärzten wurde dieser Fragebogen validiert: Konfirmatorische Faktorenanalysen zeigen befriedigende bis gute Fit-Indizes. Die internen Konsistenzen der Fragebogenskalen sind ausreichend bis sehr gut, für die Interraterübereinstimmung zeigen sich befriedigende Ergebnisse. Die Skaleninterkorrelationen sprechen für eine gute Konstruktvalidität. Korrelationen und multiple Regressionsanalysen mit mehreren Befindensvariablen bekräftigen die Bedeutsamkeit der Skalen im Stressgeschehen von Ärztinnen und Ärzten. Damit liegt ein Fragebogen vor, mit dem die Arbeitsbedingungen von Klinikärztinnen und -ärzten reliabel und valide bewertet werden können, und der einen ersten Schritt zur Verbesserung ihrer Arbeitsbedingungen ermöglicht.
Genetic Links Between Temperamental Traits of the Regulative Theory of Temperament and the Big Five
Authors: Kandler Christian , Held Lydia , Kroll Caroline , Bergeler Alina , Riemann Rainer , Angleitner Alois
Published: December 2012

This study investigated the phenotypic, genetic, and environmental relationships between Big Five personality traits and temperamental traits on the basis of the regulative theory of temperament (RTT) using a multitrait-multimethod twin dataset. This allowed us to test specific hypotheses of the five factor theory (FFT) and the RTT. The Big Five personality factors were measured with the Neuroticism-Extraversion-Openness Five-Factor Inventory (NEO-FFI). The six regulatory temperamental traits were captured by the Formal Characteristics of Behavior-Temperament Inventory (FCB-TI). We analyzed self-reports as well as averaged peer ratings from 737 monozygotic and 395 dizygotic twins. Results showed phenotypic links between Big Five and RTT traits that could be attributed mainly to genetic factors. Genetic influences on the variance in Big Five personality traits did not account for the vast majority of genetic variance in all temperamental traits of the RTT contradicting the hypothesis of the FFT that the Big Five exhaustively cover basic temperamental traits. In line with the RTT, the FCB-TI scales showed large genetic links to Neuroticism and Extraversion and rather small links to Openness, Agreeableness, and Conscientiousness, supporting the idea of a differentiation between regulative and integrative aspects of personality.
DIPRA: A user‐friendly program to model multi‐element diffusion in olivine with applications to timescales of magmatic processes
Authors: Girona Társilo , Costa Fidel
Published: December 2012

Modeling the diffusion of elements in olivine from volcanic rocks has recently become one of the most useful techniques to determine the timescales of the processes that occur in magma reservoirs before eruptions. However, many potential users are not versed in the numerical methods needed to solve the diffusion equation for timescale determinations. Here we present DIPRA (Diffusion Process Analysis), a user‐friendly computer tool that models easily and intuitively the olivine chemical zoning by performing an automatic, visual, and quick fit to the natural profiles. The code is developed under a finite difference scheme and allows simultaneous modeling of diffusion of Fe, Mg, Mn, Ni, and Ca. DIPRA accounts for most variables that affect the diffusivity, including temperature, pressure, oxygen fugacity, major element composition, and anisotropy. Initial and boundary conditions can be done as complex as desired, including changing boundary composition with time. Such versatility allows modeling the large variety of scenarios that are characteristic of volcanic systems. We also have implemented a methodology to estimate objectively the uncertainties of the timescales from the uncertainties of the data and temperature. We expect that our application will increase the number and quality of timescale determinations from crystal zoning studies. It may be also useful as a teaching resource for higher education courses.
Cluster observations of kinetic structures and electron acceleration within a dynamic plasma bubble
Authors: Zhou Meng , Deng Xiaohua , Ashour‐Abdalla Maha , Walker Raymond , Pang Ye , Tang Chaoling , Huang Shiyong , El‐Alaoui Mostafa , Yuan Zhigang , Li Huimin
Published: December 2012

Fast plasma flows are believed to play important roles in transporting mass, momentum, and energy in the magnetotail during active periods, such as the magnetospheric substorms. In this paper, we present Cluster observations of a plasma‐depleted flux tube, i.e., a plasma bubble associated with fast plasma flow before the onset of a substorm in the near‐Earth tail around X = −18 RE. The bubble is bounded by both sharp leading (∂bz/∂x < 0) and trailing (∂bz/∂x > 0) edges. The two edges are thin current layers (approximately ion inertial length) that carry not only intense perpendicular current but also field‐aligned current. The leading edge is a dipolarization front (DF) within a slow plasma flow, while the trailing edge is embedded in a super‐Alfvénic convective ion jet. The electron jet speed exceeds the ion flow speed thus producing a large tangential current at the trailing edge. The electron drift is primarily given by the E × B drift. Interestingly, the trailing edge moves faster than the leading edge, which causes shrinking of the bubble and local flux pileup inside the bubble. This resulted in a further intensification of Bz, or a secondary dipolarization. Both the leading and trailing edges are tangential discontinuities that confine the electrons inside the bubble. Strong electron acceleration occurred corresponding to the secondary dipolarization, with perpendicular fluxes dominating the field‐aligned fluxes. We suggest that betatron acceleration is responsible for the electron energization. Whistler waves and lower hybrid drift waves were identified inside the bubble. Their generation mechanisms and potential roles in electron dynamics are discussed.
Changes in the Earth's magnetic field over the past century: Effects on the ionosphere‐thermosphere system and solar quiet (Sq) magnetic variation
Authors: Cnossen Ingrid , Richmond Arthur D.
Published: December 2012

We investigated the contribution of changes in the Earth's magnetic field to long‐term trends in the ionosphere, thermosphere, and solar quiet (Sq) magnetic variation using the Coupled Magnetosphere‐Ionosphere‐Thermosphere (CMIT) model. Simulations with the magnetic fields of 1908, 1958, and 2008 were done. The strongest differences occurred between ~40°S–40°N and ~100°W–50°E, which we refer to as the Atlantic region. The height and critical frequency of the F2 layer peak, hmF2 and foF2, changed due to changes in the vertical E × B drift and the vertical components of diffusion and transport by neutral winds along the magnetic field. Changes in electron density resulted in changes in electron temperature of the opposite sign, which in turn produced small corresponding changes in ion temperature. Changes in neutral temperature were not statistically significant. Strong changes in the daily amplitude of the Sq variation occurred at low magnetic latitudes due to the northward movement of the magnetic equator and the westward drift of the magnetic field. The simulated changes in hmF2, foF2, and Sq amplitude translate into typical trends of ±1 km/decade (night) to ±3 km/decade (day), −0.1 to +0.05 MHz/decade, and ±5 to ±10 nT/century, respectively. These are mostly comparable in magnitude to observed trends in the Atlantic region. The simulated Atlantic region trends in hmF2 and foF2 are ~2.5 times larger than the estimated effect of enhanced greenhouse gases on hmF2 and foF2. The secular variation of the Earth's magnetic field may therefore be the dominant cause of trends in the Atlantic region ionosphere.
An analysis of the current deflection around Dongsha Islands in the northern South China Sea
Authors: Wang Dongxiao , Wang Qiang , Zhou Weidong , Cai Shuqun , Li Li , Hong Bo
Published: December 2012

Based on the in situ data and ADCP observation in fall, it is found that a northeastward current at inter‐middle level flows on the Northern South China Sea (NSCS) continental shelf. This current flows almost along the isobaths, and it deflects from the isobaths veering toward deep water when flowing over the Dongsha Islands. Geographic currents derived from the climatologic hydrography data (WOA01) and absolute dynamic topography (ADT) data confirm the deflection of the northeastward current on NSCS continent. A fine resolution regional ocean model which can well reproduce the large scale circulation in the NSCS is used to analyze the dynamic about the deflection. The vorticity term balances shows that JEBAR (Joint Effect of Baroclinicity and Relief) drives the water column to depart from the isobaths. To the east of the Dongsha Islands, the isopycnal is almost orthogonal to the isobaths. The joint effect of the topographic and the baroclinic effect supplies negative vorticity and drives the water column to deflect from the isobaths and veer to deeper water. Momentum analysis along the stream line shows that, when the sea water flows around the Dongsha islands, the pressure gradient along the isobath pushes the sea water to accelerate, and then the Coriolis force orthogonal to the isobath increases and overcomes the corresponding pressure gradient, which drives the water deflected from the isobath toward the deep sea.
Uncertainty assessment of quantifying spatially concentrated groundwater discharge to small streams by distributed temperature sensing
Authors: Lauer Florian , Frede Hans‐Georg , Breuer Lutz
Published: December 2012

Key Points

Low artificially created inflow fractions could be detected

Quantitative results are comparably to directly measured inflow fractions

Uncertainty gets larger closer to the detection limits
Butyrate-producing Clostridium cluster XIVa species specifically colonize mucins in an in vitro gut model
Authors: Van den Abbeele Pieter , Belzer Clara , Goossens Margot , Kleerebezem Michiel , De Vos Willem M , Thas Olivier , De Weirdt Rosemarie , Kerckhof Frederiek-Maarten , Van de Wiele Tom
Published: December 2012

The human gut is colonized by a complex microbiota with multiple benefits. Although the surface-attached, mucosal microbiota has a unique composition and potential to influence human health, it remains difficult to study in vivo. Therefore, we performed an in-depth microbial characterization (human intestinal tract chip (HITChip)) of a recently developed dynamic in vitro gut model, which simulates both luminal and mucosal gut microbes (mucosal-simulator of human intestinal microbial ecosystem (M-SHIME)). Inter-individual differences among human subjects were confirmed and microbial patterns unique for each individual were preserved in vitro. Furthermore, in correspondence with in vivo studies, Bacteroidetes and Proteobacteria were enriched in the luminal content while Firmicutes rather colonized the mucin layer, with Clostridium cluster XIVa accounting for almost 60% of the mucin-adhered microbiota. Of the many acetate and/or lactate-converting butyrate producers within this cluster, Roseburia intestinalis and Eubacterium rectale most specifically colonized mucins. These 16S rRNA gene-based results were confirmed at a functional level as butyryl-CoA:acetate-CoA transferase gene sequences belonged to different species in the luminal as opposed to the mucin-adhered microbiota, with Roseburia species governing the mucosal butyrate production. Correspondingly, the simulated mucosal environment induced a shift from acetate towards butyrate. As not only inter-individual differences were preserved but also because compared with conventional models, washout of relevant mucin-adhered microbes was avoided, simulating the mucosal gut microbiota represents a breakthrough in modeling and mechanistically studying the human intestinal microbiome in health and disease. Finally, as mucosal butyrate producers produce butyrate close to the epithelium, they may enhance butyrate bioavailability, which could be useful in treating diseases, such as inflammatory bowel disease.
High-resolution NMR studies of structure and dynamics of human ERp27 indicate extensive interdomain flexibility
Authors: Amin Nader T. , Wallis A. Katrine , Wells Stephen A. , Rowe Michelle L. , Williamson Richard A. , Howard Mark J. , Freedman Robert B.
Published: December 2012

ERp27 (endoplasmic reticulum protein 27.7 kDa) is a homologue of PDI (protein disulfide-isomerase) localized to the endoplasmic reticulum. ERp27 is predicted to consist of two thioredoxin-fold domains homologous with the non-catalytic b and b′ domains of PDI. The structure in solution of the N-terminal b-like domain of ERp27 was solved using high-resolution NMR data. The structure confirms that it has the thioredoxin fold and that ERp27 is a member of the PDI family. 15N-NMR relaxation data were obtained and ModelFree analysis highlighted limited exchange contributions and slow internal motions, and indicated that the domain has an average order parameter S2 of 0.79. Comparison of the single-domain structure determined in the present study with the equivalent domain within full-length ERp27, determined independently by X-ray diffraction, indicated very close agreement. The domain interface inferred from NMR data in solution was much more extensive than that observed in the X-ray structure, suggesting that the domains flex independently and that crystallization selects one specific interdomain orientation. This led us to apply a new rapid method to simulate the flexibility of the full-length protein, establishing that the domains show considerable freedom to flex (tilt and twist) about the interdomain linker, consistent with the NMR data.
Theoretical investigations of the electronic states of NaXe: A comparative study
Authors: Salem F. Ben , Rhouma M. Ben El Hadj , Spiegelman F. , Mestdagh J.-M. , Hochlaf M.
Published: December 2012

The electronic state properties of NaXe are investigated using ab initio methodologies and various pseudopotential approaches for comparison. The spectroscopic terms and dipole moments of the lowest electronic states up to the Na(3d) +Xe dissociation limit are determined. The difference between valence or smaller core pseudopotential on Xe is shown to be negligible and so is the difference between all-electron and valence pseudopotential completed by core-polarization treatments of Na. These calculations are used as references to test the performance of a treatment involving a zero electron pseudopotential description of xenon together with a one-electron pseudopotential description of Na. When compared with the reference calculations, the one-electron model leads to reasonable quantitative results. The potential energy curves and spectroscopic data of all Rydberg excited states of NaXe up the Na(5f)+Xe dissociation limit are determined using this method. Long distance wells and barriers in the range R = 15–40 bohrs are identified for some of the higher states with 2Σ+ symmetry.
Skew photonic Doppler velocimetry to investigate the expansion of a cloud of droplets created by micro-spalling of laser shock-melted metal foils
Authors: Loison D. , de Rességuier T. , Dragon A. , Mercier P. , Benier J. , Deloison G. , Lescoute E. , Sollier A.
Published: December 2012

Dynamic fragmentation in the liquid state after shock-induced melting, usually referred to as micro-spallation, is an issue of great interest for both basic and applied sciences. Recent efforts have been devoted to the characterization of the resulting ejecta, which consist in a cloud of fine molten droplets. Major difficulties arise from the loss of free surface reflectivity at shock breakout and from the wide distribution of particle velocities within this cloud. We present laser shock experiments on tin and aluminium, to pressures ranging from about 70 to 160 GPa, with complementary diagnostics including a photonic Doppler velocimeter set at a small tilt angle from the normal to the free surface, which enables probing the whole cloud of ejecta. The records are roughly consistent with a one-dimensional theoretical description accounting for laser shock loading, wave propagation, phase transformations, and fragmentation. The main discrepancies between measured and calculated velocity profiles are discussed in terms of edge effects evidenced by transverse shadowgraphy.
Large in-plane permittivity of Ba0.6Sr0.4TiO3 thin films crystallized using excimer laser annealing at 300 °C
Authors: Kang Min-Gyu , Cho Kwang-Hwan , Ho Do Young , Lee Young-Jin , Nahm Sahn , Yoon Seok-Jin , Kang Chong-Yun
Published: December 2012

We demonstrated a way to fabricate the crystalline Ba0.6Sr0.4TiO3 (BST) thin films using excimer laser annealing technique on the amorphous BST thin films fabricated by sol-gel process. The grain size of the laser-annealed films is larger than that of the conventionally thermal-annealed films. However, an uncrystallized, amorphous layer was observed near the film/substrate interface due to the limited laser absorption depth. The uncrystallized layer has a critical influence on out-of-plane dielectric property of BST films. The significant difference of the relative dielectric permittivity (εr) between in-plane (1383) and out-of-plane (184) directions is observed.
Modulation instability of an intense laser beam in the hot magnetized electron-positron plasma in the quasi-neutral limit
Authors: Sepehri Javan N.
Published: December 2012

The aim of the present study is to investigate the problem of modulation instability of an intense laser beam in the hot magnetized electron-positron plasma. Propagation of the intense circularly polarized laser beam along the external magnetic field is studied using a relativistic fluid model. A nonlinear equation describing the interaction of the laser pulse with the magnetized hot pair plasma is derived based on the quasi-neutral approximation, which is valid for the hot plasma. Also, the nonlinear dispersion equation for the hot plasma is obtained. The growth rate of the instability is calculated and its dependence on temperature and external magnetic field are considered.
Polylithiated (OLi2) functionalized graphane as a potential hydrogen storage material
Authors: Hussain Tanveer , Adit Maark Tuhina , De Sarkar Abir , Ahuja Rajeev
Published: December 2012

Hydrogen storage capacity, stability, bonding mechanism, and the electronic structure of polylithiated molecules (OLi2) functionalized graphane (CH) has been studied by means of first principle DFT. Molecular dynamics have confirmed the stability, while Bader charge analysis describes the bonding mechanism of OLi2 with CH. The binding energy of OLi2 on CH sheet has been found to be large enough to ensure its uniform distribution without any clustering. It has been found that each OLi2 unit can adsorb up to six H2 molecules resulting into a storage capacity of 12.90 wt. % with adsorption energies within the range of practical H2 storage application.
Direct observation of giant metallic domain evolution driven by electric bias in VO2 thin films on TiO2(001) substrate
Authors: Kanki Teruo , Kawatani Kenichi , Takami Hidefumi , Tanaka Hidekazu
Published: December 2012

We report on conductive changes caused by electric bias-driven insulator-to-metal transition in VO2 thin films on a TiO2(001) substrate and observe the evolution of giant metallic domains to reveal their microscopic origin. The metallic domains are anisotropically formed along the direction of applied current or voltage. This anisotropic formation of metallic states causes abrupt increase of conductivity when the fraction rate of metallic states is low, conforming with the directed percolation model. Our results illustrate the importance of spatially localized phase transitions to tune conductive behavior.
Investigation of the thermal charge “trapping-detrapping” in silicon nanocrystals: Correlation of the optical properties with complex impedance spectra
Authors: Ishii Masashi , Crowe Iain F. , Halsall Matthew P. , Knights Andrew P. , Gwilliam Russell M. , Hamilton Bruce
Published: December 2012

The charge confinement in silicon nanocrystals over the temperature range 35–300 K was investigated by complex impedance spectroscopy (CIS). A charge response found in the “dark” (i.e., no laser pumping) CIS spectrum indicated a frequency shift with temperature, which was well correlated with the temperature dependent photoluminescence (PL) intensity. From equivalent circuit analyses of this frequency shift, we were able to determine the charge “trapping-detrapping” mechanism giving rise to the luminescence. We find that the luminescence decay transient, expressed as a stretched exponential function, can be mathematically converted to a CIS spectrum.
Reassembling the Event: Estonia's ‘Bronze Night’
Authors: Kaiser Robert
Published: December 2012

At the end of April 2007, an event unfolded in Tallinn, Estonia, that came to be called the ‘Bronze Night’. Most of the research on this event—and on events in general—uses an after-the-act representational approach that treats events as effects whose cause lies elsewhere, external to the event in its becoming. Partially because of this, most research into events emphasizes temporal path-dependency and all but ignores the spatiality of events. Following Deleuze's philosophy of the event, I seek to learn from the Bronze Night as an event by using an in-the-act procedure of reassemblage. In reassembling the event, I pay special attention to its spatiality: to processes of deterritorialization and reterritorialization, to event-spaces produced and partially captured, and to the event's transitivity to new spaces. The paper ends with a discussion of the ways in which the conditions of the problem that actualized the event were newly determined in and through the event, creating opportunities for the event's counteractualization.
Binning, Gifting and Recovery: The Conduits of Disposal in Household Food Consumption
Authors: Evans David
Published: December 2012

This paper explores the movements and placings that work to configure food as waste. At issue here—following the work of Nicky Gregson, Kevin Hetherington, and Rolland Munro—are the multiple conduits that exist for ‘moving things along’ and the idea that consumption research needs to move beyond the unfortunate conjunction of disposal and waste. I suggest that the disposal of surplus food is enacted via a graduated process in which it first enters a ‘gap’ where ambiguities and anxieties surrounding its residual value and onward trajectory are addressed. Drawing on ethnographic examples, I explore the shifting contours and gradients that reduce the possibilities for disposing of food through conduits in which it can be handed down, handed around, or otherwise saved from wastage. I also unpack the overwhelming tendency for surplus food to be cast as ‘excess’ and placed in conduits—typically the bin—that connect it to the waste stream. Crucially, it is suggested that food is a specific genre of material culture and that this underpins the normativity of its binning alongside the attendant prevention of its recirculation or recovery. To conclude, I reflect on the broader implications of this analysis for understandings of consumption, disposal, and waste.
Racial Violence and the Cosmopolitan City
Authors: Mawani Renisa
Published: December 2012

In this paper I argue that cosmopolitanisms, as visions of living with difference, and race and racisms, as political regimes of subjection and subjectification, are mutually constitutive. Although scholars have made similar claims regarding earlier versions of cosmopolitanisms, developed largely from the work of Immanuel Kant, recent proponents have conceptualized their renewed formulations, detached from Eurocentric histories and newly expanded to include the migrant, refugee, and subaltern, as promissory visions of conviviality and often as an antidote to racisms. Despite efforts to expand cosmopolitanisms to include racial subjects previously excluded, these visions may be productive of new, renewed, and changing forms of racial subjection. Specifically, I argue that racisms are an immanent and organizing logic manifest in the production of racial heterogeneities and differentiations upon which cosmopolitical visions depend and also generative of the cosmopolitan outlook these encounters are thought to require. To situate and develop these claims, I open with a 1907 sketch published in the Illustrated London News which depicts Vancouver, Canada both as “the most cosmopolitan city in the world” (Begg, 1907, page 476) and as a site of anti-Asian violence. Approaching this image both as a historical example and as an opening for critical inquiry, I untangle the constitutive relations between racisms and cosmopolitanisms through the labor demands of global capitalism and in the cultivated indifference that is frequently identified as the hallmark of a cosmopolitan disposition. While the conjoined forces of colonialism and capitalism effectuated the historico-material basis of ethnoracial difference, what some have termed an ‘ordinary cosmopolitanism’, these conditions did not lead to conviviality alone. Rather, in racially charged colonial Vancouver, the indifference that Europeans putatively expressed in their encounters with migrants from China, Japan, and later India, commonly erupted into racial enmity and violence. What might this historical example afford to contemporary discussions regarding the present and future of the new cosmopolitanisms?