bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving information density in ferroelectric polymer films by using nanoimprinted gratings
Authors: Martínez-Tong D. E. , Soccio M. , García-Gutiérrez M. C. , Nogales A. , Rueda D. R. , Alayo N. , Pérez-Murano F. , Ezquerra T. A.
Published: May 2013

In this work, well-defined low aspect ratio nanostructures based on nanogratings on thin films of poly(vinylidene fluoride–trifluoroethylene) copolymers were prepared. By using these nanogratings, an improved management of writing and reading information of about 500 Gbit/in.2 (0.01 bit/nm2) can be reached as revealed by Piezoresponse Force Microscopy. Structural investigation by means of X-ray diffraction techniques indicates that the physical confinement generated by nanoimprint promotes the development of smaller and edge-on oriented crystals. Our results evidence that one-dimensional nanostructuring can be a straightforward approach to improve the control of the polarization in ferroelectric polymer thin films.
Communication: Dynamical embedding: Correct quantum response from coupling TDDFT for a small cluster with classical near-field electrodynamics for an extended region
Authors: Gao Yi , Neuhauser Daniel
Published: May 2013

We show how to obtain the correct electronic response of a large system by embedding; a small region is propagated by TDDFT (time-dependent density functional theory) simultaneously with a classical electrodynamics evolution using the Near-Field method over a larger external region. The propagations are coupled through a combined time-dependent density yielding a common Coulomb potential. We show that the embedding correctly describes the plasmonic response of a Mg(0001) slab and its influence on the dynamical charge transfer between an adsorbed H2O molecule and the substrate, giving the same spectral shape as full TDDFT (similar plasmon peak and molecular-dependent differential spectra) with much less computational effort. The results demonstrate that atomistic embedding electrodynamics is promising for nanoplasmonics and nanopolaritonics.
Importance of the localization for inter-subband scattering rates in quasi two-dimensional structures
Authors: Ndebeka-Bandou C. , Carosella F. , Ferreira R. , Bastard G.
Published: May 2013

The inter-subband scattering in quasi two-dimensional heterostructures is critically examined in the case of cascade structures with a double well design. We show that when two kinds of elastic scatterers are present, the scattering frequencies may markedly differ from the one evaluated for plane wave states for the in-plane motion at the Born approximation. We argue that this feature results from the disorder-induced spatial localization of the eigenstates in the layer plane. The scatterer location dependence of the scattering frequencies is also discussed. At low concentration the in-plane localization is found to increase the inter-subband scattering.
Effect of the short collection length in silicon microscale wire solar cells
Authors: Kim Hyunyub , Kim Joondong , Lee Eunsongyi , Kim Dong-Wook , Yun Ju-Hyung , Yi Junsin
Published: May 2013

Electrical and optical properties of silicon microscale wire (SiMW) solar cells were investigated. Diverse designs were applied for SiMW geometries as light absorbers. Finite-difference time-domain simulation shows a focused optical field in the wires inducing an optical absorption enhancement in SiMW solar cells. SiMW solar cells provided remarkably higher Voc values (0.597-0.61 V) than that of the planar solar cell (0.587 V). As for the electrical aspects, the position of the space charge region in a SiMW directly affects the carrier collection efficiency according to the SiMW diameter and significantly modulates the photogenerated-currents and voltages in solar cells.
Increased open-circuit voltage in a Schottky device using PbS quantum dots with extreme confinement
Authors: Choi Hyekyoung , Kwan Kim Jun , Hoon Song Jung , Kim Youngjo , Jeong Sohee
Published: May 2013

We fabricated the PbS nanocrystal quantum dots (NQDs) based Schottky structure device (ITO/PbS/LiF/Al) with varying bandgap of NQDs from 0.8 to 2.2 eV. The open-circuit voltage increased monotonically with NQD's bandgap until 0.67 V, achieved using extremely confined, 1.5 nm sized-PbS NQDs. The power conversion efficiency reached the maximum value over 3% under AM 1.5 with NQD's bandgap of about 1.3 eV. Size-dependent photovoltaic evaluation in extreme confinement regime provides basis for efficient multi-junction solar cells composed of PbS NQDs of different sizes.
Imaging a nuclear reactor using cosmic ray muons
Authors: Perry John , Azzouz Mara , Bacon Jeffrey , Borozdin Konstantin , Chen Elliott , Fabritius Joseph , Milner Edward , Miyadera Haruo , Morris Christopher , Roybal Jonathan , Wang Zhehui , Busch Bob , Carpenter Ken , Hecht Adam A. , Masuda Koji , Spore Candace , Toleman Nathan , Aberle Derek , Lukić Zarija
Published: May 2013

The passage of muons through matter is dominated by the Coulomb interaction with electrons and nuclei. The muon interaction with electrons leads to continuous energy loss and stopping of the muons. The muon interaction with nuclei leads to angular diffusion. We present experimental images of a nuclear reactor, the AGN-201M reactor at the University of New Mexico, using data measured with a particle tracker built from a set of sealed drift tubes. The data are compared with a geant4 model. In both the data and simulation, we identify specific regions corresponding to elements of the reactor structure, including its core, moderator, and shield.
Effect of excited states on the ground-state modulation bandwidth in quantum dot lasers
Authors: Wu Yuchang , Suris Robert A. , Asryan Levon V.
Published: May 2013

We consider direct and indirect (excited-state-mediated) capture of carriers from the waveguide region into the lasing ground state in quantum dots (QDs) and calculate the modulation response of a QD laser. We show that, when only indirect capture is involved, the excited-to-ground-state relaxation delay strongly limits the ground-state modulation bandwidth of the laser—at the longest tolerable relaxation time, the bandwidth becomes zero. When direct capture is also involved, the effect of excited-to-ground-state relaxation is less significant and the modulation bandwidth is considerably higher.
Enhanced bias stress stability of a-InGaZnO thin film transistors by inserting an ultra-thin interfacial InGaZnO:N layer
Authors: Huang Xiaoming , Wu Chenfei , Lu Hai , Ren Fangfang , Chen Dunjun , Zhang Rong , Zheng Youdou
Published: May 2013

Amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistors (TFTs) having an ultra-thin nitrogenated a-IGZO (a-IGZO:N) layer sandwiched at the channel/gate dielectric interface are fabricated. It is found that the device shows enhanced bias stress stability with significantly reduced threshold voltage drift under positive gate bias stress. Based on x-ray photoelectron spectroscopy measurement, the concentration of oxygen vacancies within the a-IGZO:N layer is suppressed due to the formation of N-Ga bonds. Meanwhile, low frequency noise analysis indicates that the average trap density near the channel/dielectric interface continuously drops as the nitrogen content within the a-IGZO:N layer increases. The improved interface quality upon nitrogen doping agrees with the enhanced bias stress stability of the a-IGZO TFTs.
Two-stage processes of electrically induced-ferroelectric to relaxor transition in 0.94(Bi1/2Na1/2)TiO3-0.06BaTiO3
Authors: Jo Wook , Daniels John , Damjanovic Dragan , Kleemann Wolfgang , Rödel Jürgen
Published: May 2013

The stability of electrically induced long-range ferroelectric order in a relaxor 0.94(Bi1/2Na1/2)TiO3-0.06BaTiO3 ceramic material has been investigated by temperature-dependent X-ray diffraction and electrical property measurements. The depolarization and ferroelectric-to-relaxor transition are identified as separate and discrete processes. It is observed that the induced ferroelectric domains first lose their ferroelectric/ferroelastic texture coincident with a peak signal in the thermally induced depolarization current. With further increase in temperature, the detextured ferroelectric domains are dissociated into nanoscale entities. This fragmentation marks the ferroelectric-to-relaxor transition. It is suggested that the ferroelectric-to-relaxor transition has features of a second order phase transition.
Spatial relationships of sympatric wolves (Canis lupus) and coyotes (C. latrans) with woodland caribou (Rangifer tarandus caribou) during the calving season in a human-modified boreal landscape
Authors: Latham A. David M. , Latham M. Cecilia , Boyce Mark S. , Boutin Stan
Published: May 2013

Context Woodland caribou (Rangifer tarandus caribou) populations have declined across most of North America. Wolf (Canis lupus) predation on adults is partially responsible for declines; however, caribou declines also can be attributed to low calf survival. Wolves and invading coyotes (C. latrans) may contribute to mortality of calves. Aim We assessed wolf and coyote food habits and population and individual level selection for caribou-preferred habitats (bogs and fens) during the caribou calving season (15 April to 30 June) in north-eastern Alberta, Canada, to determine what role these predators might play as a mortality factor for caribou calves. Methods We deployed global positioning system and very high-frequency (VHF) radio-collars on 32 wolves and nine coyotes in January 2006 – January 2008, and VHF collars on 42 adult female caribou individuals in 2003–08. We assessed wolf and coyote habitat selection using used-available resource-selection functions, and spatial overlap of wolves and coyotes with caribou using logistic regression to estimate coefficients for latent selection-difference functions. We collected and analysed scats to assess wolf and coyote food habits. Key results Wolves generally avoided caribou-preferred habitats, particularly bogs. Most coyotes selected caribou-preferred habitats (bogs and/or fens); however, relative to caribou, they were found closer to upland forests. Hair from adult and calf caribou was uncommon in wolf and coyote diet and caribou is likely to be an uncommon alternative prey for these predators. Conclusions We found that >25% of wolf packs and most coyotes selected caribou-preferred habitats during the calving season. Although caribou was not an important prey, limited secondary predation, by these predators and black bears (Ursus americanus), on adult and calf caribou is likely to be contributing to caribou population declines. Implications We caution that predation on caribou is likely to escalate as coyotes expand into this region and increasing human disturbance continues to create habitat for white-tailed deer (Odocoileus virginianus), which is an important prey for both wolves and coyotes.
Shrinking the Haystack: Using an AUV in an Integrated Ocean Observatory to Map Atlantic Sturgeon in the Coastal Ocean
Authors: Oliver Matthew J , Breece Matthew W , Fox Dewayne A , Haulsee Danielle E , Kohut Josh T , Manderson John , Savoy Tom
Published: May 2013

Physical processes in the coastal Mid-Atlantic create a complex and dynamic seascape. Understanding how coastal fishes respond to this complexity has been a major motivation in establishing coastal biotelemetry arrays. Most coastal arrays maximize the probability offish detection by positioning hydrophones near geophysical bottlenecks. The development of a real-time ocean observatory allows for synchronous mapping of dynamic hydrographic structures important to coastal fishes. These observations provide important context for interpreting the impact of oceanographic features on the behavior of telemetered animals. In a proofofconcept mission, we deployed a Slocum glider in a real-time ocean observatory to demonstrate how mobile listening assets could be dynamically reallocated in response to the mesoscale physics of the coastal ocean. The Slocum glider detected four Atlantic Sturgeon Acipencer oxyrinchus oxyrinchus that were in a shallow, well-mixed, and relatively warm and fresh water mass in a region of historic Atlantic Sturgeon bycatch.

RESUMEN

los procesos fisicos que ocurren en zona costera del Atlántico medio generan un paisaje complejo y dinámico. La comprensión de cómo los peces costeros responden a tal complejidad ha sido una motivación importante para establecer un arreglo de biotelemetría en la franja costera. Muchos de los arreglos costeros maximizan la probabilidad de detector peces mediante el uso de hidrófonos cerca de los cuellos de botella geofisicos. El desarrollo de un observatorio oceánico de monitoreo en tiempo real permite un mapeo sincrónico de estructuras hidrográficas dinámicas que son relevantes para los peces costeros. Estas observaciones bindan el contexto para interpretar el impacto que tienen ciertos rasgos oceanográficos en el comportamiento de animates rastreados mediante telemetría. En una misión diseñada para probar este concepto, se desplegó el deslizador Slocum en un observatorio oceánico para demostrar cómo los aparatos móviles de monitoreo pueden ser reubicados de forma dinámica en respuesta a procesos fisicos de mesoescala que ocurren en el océano costero. El deslizador Slocum detectó cuatro especímenes de esturión del Atlántico Acipencer oxyrinchus oxyrinchus encontrados en una masa de agua fresca, somera y relativamente cálida en una region en la que históricamente el esturión del Atlántico ha sido parte de la captura incidental.
pH Dynamics of Tricaine Methanesulfonate (MS-222) in Fresh and Artificial Seawater
Authors: Christiansen Emily Fenimore , Stoskopf Michael K
Published: May 2013

Tricaine methanesulfonate (MS-222) solutions are used routinely for clinical and experimental anesthesia of a variety of aquatic organisms. It is commonly accepted that MS-222 alters pH when added to freshwater, and buffering freshwater anesthetic solutions is considered to be the standard of care. However, buffering saltwater solutions is considered by many to be unnecessary; some individuals question whether any water with high natural mineral hardness needs to be buffered when MS-222 is added. To assess the need for buffering, we studied the dynamics of pH change when adding clinically relevant amounts of MS-222 to artificial seawater and to freshwater of varying hardness. We found that artificial seawater does not possess adequate buffering capacity to prevent a physiologically significant drop in pH when MS-222 is added, and hardness does not accurately predict the reaction of water pH to the addition of MS-222 in clinically relevant concentrations. Our data for salt water suggest that MS-222 solutions should be buffered to saturation with sodium bicarbonate and in freshwater should be titrated to the particular water source to satisfy the optimal pH of the species being anesthetized.
Controlling Mortality Caused by External Columnaris in Largemouth Bass and Bluegill with Chloramine-T or Hydrogen Peroxide
Authors: Bowker James D , Carty Daniel , Trushenski Jesse T , Bowman Molly P , Wandelear Niccole , Matthews Michael
Published: May 2013

Columnaris (causative agent, Flavobacterium columnare) is a widespread fish disease of concern among fish culturists in the USA. If left untreated, an entire population of fish may become infected, and morbidity and mortality may reach high levels. In virtually all instances, columnaris outbreaks require intervention to prevent significant losses. A number of sanitizing agents, most notably chloramine-T (CLT) and hydrogen peroxide (HP), have been used to control mortality associated with a variety of bacterial pathogens causing external infections. However, the majority of trials conducted to demonstrate the effectiveness of these chemicals, thereby gaining U.S. Food and Drug Administration approval for their use in treating fish infected with columnaris, have been conducted on salmonids. Accordingly, we conducted seven experiments to evaluate the effectiveness of CLT or HP to control mortality associated with external columnaris in Florida Largemouth Bass Micropterus salmoides floridanus and Bluegill Lepomis macrochirus. Treatment with CLT or HP significantly reduced cumulative mortality in five of the seven experiments. Cumulative mortality was strongly correlated to pretreatment mortality in treated and control tanks in the five Largemouth Bass experiments, suggesting that intervention at later stages of columnaris progression may result in less favorable outcomes. Odds ratios calculated for individual experiments indicated varying degrees of success in controlling mortality; however, meta-analysis of all experiments indicated treatment with either CLT or HP significantly increased probability of survival, regardless of fish species or test article. These results demonstrate that both chemicals can be effective in controlling mortality associated with external columnaris in Largemouth Bass and Bluegills and that timely treatment of fish will likely result in lower overall mortality.
Growth of Juvenile Scup Fed Two Commercial Diets
Authors: Perry Dean M , Redman Dylan H , Mercaldo-Allen Renee , Kuropat Catherine A , Widman James C
Published: May 2013

Juvenile Scup Stenotomus chrysops 0.35–0.95 g were fed two different commercial diets for 9 weeks to determine growth rates. Diets were hand-distributed to four replicate groups of 45 fish, four times a day. Survival among all treatments was high (90.0–92.5%), and both diets supported good growth. After five weeks, Scup fed diet 1 were significantly greater in length and weight than fish fed diet 2. These differences remained significant throughout the rest of the study. Specific growth rate (SGR) values were 5.8%/d for fish fed diet 1 and 5.5%/d for diet 2, while feed conversion ratios (FCR) were 1.22 for diet 1 and 1.25 for diet 2. Relative growth rate (RGR) values were diet 1 = 3,689% and diet 2 = 3,077%, and daily weight gain (DWG) values were diet 1 = 0.38 g/d and diet 2 = 0.31 g/d. Scup fed diet 1 had significantly greater final live weight, total length, weight gain, SGR, RGR, and DWG measurements than did fish fed diet 2. Juvenile Scup exhibited high growth rates and low feed conversion ratios when fed the two commercial diets, identifying them as a strong candidate species for commercial aquaculture.
Ligand-induced activation of a formin–NPF pair leads to collaborative actin nucleation
Authors: Graziano Brian R. , Jonasson Erin M. , Pullen Jessica G. , Gould Christopher J. , Goode Bruce L.
Published: May 2013

Formins associate with other nucleators and nucleation-promoting factors (NPFs) to stimulate collaborative actin assembly, but the mechanisms regulating these interactions have been unclear. Yeast Bud6 has an established role as an NPF for the formin Bni1, but whether it also directly regulates the formin Bnr1 has remained enigmatic. In this paper, we analyzed NPF-impaired alleles of bud6 in a bni1Δ background and found that Bud6 stimulated Bnr1 activity in vivo. Furthermore, Bud6 bound directly to Bnr1, but its NPF effects were masked by a short regulatory sequence, suggesting that additional factors may be required for activation. We isolated a novel in vivo binding partner of Bud6, Yor304c-a/Bil1, which colocalized with Bud6 and functioned in the Bnr1 pathway for actin assembly. Purified Bil1 bound to the regulatory sequence in Bud6 and triggered NPF effects on Bnr1. These observations define a new mode of formin regulation, which has important implications for understanding NPF-nucleator pairs in diverse systems.
Cellular and molecular mechanisms underlying muscular dystrophy
Authors: Rahimov Fedik , Kunkel Louis M.
Published: May 2013

The muscular dystrophies are a group of heterogeneous genetic diseases characterized by progressive degeneration and weakness of skeletal muscle. Since the discovery of the first muscular dystrophy gene encoding dystrophin, a large number of genes have been identified that are involved in various muscle-wasting and neuromuscular disorders. Human genetic studies complemented by animal model systems have substantially contributed to our understanding of the molecular pathomechanisms underlying muscle degeneration. Moreover, these studies have revealed distinct molecular and cellular mechanisms that link genetic mutations to diverse muscle wasting phenotypes.
Dynamic bonds and polar ejection force distribution explain kinetochore oscillations in PtK1 cells
Authors: Civelekoglu-Scholey Gul , He Bin , Shen Muyao , Wan Xiaohu , Roscioli Emanuele , Bowden Brent , Cimini Daniela
Published: May 2013

Duplicated mitotic chromosomes aligned at the metaphase plate maintain dynamic attachments to spindle microtubules via their kinetochores, and multiple motor and nonmotor proteins cooperate to regulate their behavior. Depending on the system, sister chromatids may display either of two distinct behaviors, namely (1) the presence or (2) the absence of oscillations about the metaphase plate. Significantly, in PtK1 cells, in which chromosome behavior appears to be dependent on the position along the metaphase plate, both types of behavior are observed within the same spindle, but how and why these distinct behaviors are manifested is unclear. Here, we developed a new quantitative model to describe metaphase chromosome dynamics via kinetochore–microtubule interactions mediated by nonmotor viscoelastic linkages. Our model reproduces all the key features of metaphase sister kinetochore dynamics in PtK1 cells and suggests that differences in the distribution of polar ejection forces at the periphery and in the middle of PtK1 cell spindles underlie the observed dichotomy of chromosome behavior.
Victor Ambros: The broad scope of microRNAs
Authors: Sedwick Caitlin
Published: May 2013

Ambros studies how microRNAs impact development.
Faithful representations of Leibniz algebras
Authors: Barnes Donald
Published: May 2013

Let

L
L

be a Leibniz algebra of dimension

n
n

. We prove the existence of a faithful

L
L

-module of dimension less than or equal to

n
+
1

n+1

.
Existence and properties of geometric quotients
Authors: Rydh David
Published: May 2013

In this paper, we study quotients of groupoids and coarse moduli spaces of stacks in a general setting. Geometric quotients are not always categorical, but we present a natural topological condition under which a geometric quotient is categorical. We also show the existence of geometric quotients of finite flat groupoids and give explicit local descriptions. Exploiting similar methods, we give an easy proof of the existence of quotients of flat groupoids with finite stabilizers. As the proofs do not use Noetherian methods and are valid for general algebraic spaces and algebraic stacks, we obtain a slightly improved version of Keel and Mori’s theorem.
Conditions favouring Bromus tectorum dominance of endangered sagebrush steppe ecosystems
Authors: Reisner Michael D. , Grace James B. , Pyke David A. , Doescher Paul S.
Published: May 2013

Ecosystem invasibility is determined by combinations of environmental variables, invader attributes, disturbance regimes, competitive abilities of resident species and evolutionary history between residents and disturbance regimes. Understanding the relative importance of each factor is critical to limiting future invasions and restoring ecosystems.

We investigated factors potentially controlling Bromus tectorum invasions into Artemisia tridentata ssp. wyomingensis communities across 75 sites in the Great Basin. We measured soil texture, cattle grazing intensity, gaps among perennial plants and plant cover including B. tectorum, biological soil crusts (BSCs) and bare soil. Using a priori knowledge, we developed a multivariate hypothesis of the susceptibility of Artemisia ecosystems to B. tectorum invasion and used the model to assess the relative importance of the factors driving the magnitude of such invasions.

Model results imply that bunchgrass community structure, abundance and composition, along with BSC cover, play important roles in controlling B. tectorum dominance. Evidence suggests abundant bunchgrasses limit invasions by limiting the size and connectivity of gaps between vegetation, and BSCs appear to limit invasions within gaps. Results also suggest that cattle grazing reduces invasion resistance by decreasing bunchgrass abundance, shifting bunchgrass composition, and thereby increasing connectivity of gaps between perennial plants while trampling further reduces resistance by reducing BSC.

Synthesis and applications. Grazing exacerbates Bromus tectorum dominance in one of North America's most endangered ecosystems by adversely impacting key mechanisms mediating resistance to invasion. If the goal is to conserve and restore resistance of these systems, managers should consider maintaining or restoring: (i) high bunchgrass cover and structure characterized by spatially dispersed bunchgrasses and small gaps between them; (ii) a diverse assemblage of bunchgrass species to maximize competitive interactions with B. tectorum in time and space; and (iii) biological soil crusts to limit B. tectorum establishment. Passive restoration by reducing cumulative cattle grazing may be one of the most effective means of achieving these three goals.
A unifying quantitative framework for exploring the multiple facets of microbial biodiversity across diverse scales
Authors: Escalas Arthur , Bouvier Thierry , Mouchet Maud A. , Leprieur Fabien , Bouvier Corinne , Troussellier Marc , Mouillot David
Published: May 2013

Recent developments of molecular tools have revolutionized our knowledge of microbial biodiversity by allowing detailed exploration of its different facets and generating unprecedented amount of data. One key issue with such large datasets is the development of diversity measures that cope with different data outputs and allow comparison of biodiversity across different scales. Diversity has indeed three components: local (α), regional (γ) and the overall difference between local communities (β). Current measures of microbial diversity, derived from several approaches, provide complementary but different views. They only capture the β component of diversity, compare communities in a pairwise way, consider all species as equivalent or lack a mathematically explicit relationship among the α, β and γ components. We propose a unified quantitative framework based on the Rao quadratic entropy, to obtain an additive decomposition of diversity (γ = α + β), so the three components can be compared, and that integrate the relationship (phylogenetic or functional) among Microbial Diversity Units that compose a microbial community. We show how this framework is adapted to all types of molecular data, and we highlight crucial issues in microbial ecology that would benefit from this framework and propose ready‐to‐use R‐functions to easily set up our approach.
Disgust and Distinction: The Case of the Jellied Eel
Authors: Rhys-Taylor Alex
Published: May 2013

Drawing on a series of ethnographic encounters collected while hanging around at a seafood stand in east London, the following article aims to explore the relationship between individual expressions of distaste and the production of class, ethnic and generational forms of distinction. Starting with the visceral expressions of distaste directed towards a seafood stand, the following paragraphs draw on a combination of historical and ethnographic data rendered through a matrix of anthropological, sociological and psychoanalytic theory, to explore the role of everyday ambient experiences and the stratifying processes that cut across the lives of the city's inhabitants. Arguing against purely biological explanations of disgust, the paper explores how social histories and cultural experience inflect gut responses to the sensoria that suffuse urban environments. Moving the focus beyond the social construction of urban sensibilities, the paper goes on to develop an account of culturally inflected forms of distaste, shaping the city and the lives of its inhabitants.
The Magic of Mundane Objects: Culture, Identity and Power in a Country Vets' Practice
Authors: Hamilton Lindsay
Published: May 2013

This article explores and extends the idea that material objects lie at the heart of many of our social, and specifically workplace, interactions. The site of exploration is an ethnography of a British farm animal veterinary surgery. Drawing upon traditional cultural studies approaches alongside contemporary sociological understandings about the place of materials in social life, the article analyses how objects function to track and structure the ways that people of different professional status experience work at a veterinary surgery. It is argued that the power of the veterinary elite in this setting is best understood by paying close attention to ‘mundane' artefacts. The article argues that such objects, having almost no meaning on their own, can become potent cultural symbols if actors have the necessary social capital to ‘transform’ them. Here, Latimer's concept of ‘strong moves’ (2004) is extended to consider how the reinterpretation of objects might constitute a form of ‘cultural magic’. This article seeks to uncover some of the practical scenarios in which such ‘magical’ transformations play out and describes, through a series of tales from the field ( Van Maanen, 1985 ), the ways in which vets control and regulate their interactions with those outside the professional elite.
Maternal Situations: Sectarianism and Civility in a Divided City
Authors: Smyth Lisa , McKnight Martina
Published: May 2013

This paper explores the tensions between civility and sectarianism in contemporary Belfast. Drawing on interviews with mothers engaged in raising young children in the largely working-class and divided inner city, the paper offers a situated account of the dynamics of social reproduction and change. This is pursued through an analysis of the interplay between expectations of civility and sectarianism in three situations: walking, shopping and playing. The tensions and dilemmas of maternal action as the divided inner city is navigated indicate the gendered character of civility, an important emerging norm facilitating social change in the post-conflict era. The situation of motherhood itself, both at the centre of ethno-national reproduction and at the interface of public and private life, is not insignificant in routinely drawing mothers into the everyday dynamics of post-conflict continuity and change.
Dynamic Moral Hazard and Executive Stock Options
Authors: Dong Baomin , Guo Guixia , Wang Frank Yong
Published: May 2013

This paper shows that the optimal executive compensation scheme in a dynamic moral hazard environment is convex in the firm value. This implies that the optimal contract should include stock options. This is because the private benefit of shirking is increasing in firm value and the manager's utility is concave. Therefore, in contrast to the previous literature that takes stock options in the incentive contract exogenously, we rationalize the optimality of their use endogenously. Moreover, we show that the optimal amount of stock options (restricted stocks) increases with agency cost and the executive's reservation utility, decreases with the degree of risk aversion of the manager, and increases (decreases) with the firm size.
Optimal Advance Selling Strategy under Price Commitment
Authors: Zeng Chenhang
Published: May 2013

This paper studies a two‐period model of advance selling with experienced and inexperienced consumers. It concludes that advance selling weakly dominates no advance selling, and the optimal advance selling price may be at a discount, at a premium or at the regular selling price. Conditions for each possible advance selling strategy to prevail are characterized. However, without experienced consumers in the market, there are no incentives for the retailer to implement an advance selling price premium. How the consumer composition affects the retailer's optimal pricing strategy and profit is also examined.
Responses to Medicare Drug Costs among Near‐Poor versus Subsidized Beneficiaries
Authors: Fung Vicki , Reed Mary , Price Mary , Brand Richard , Dow William H. , Newhouse Joseph P. , Hsu John
Published: May 2013

Objective

There is limited information on the protective value of Medicare Part D low‐income subsidies (LIS). We compared responses to drug costs for LIS recipients with near‐poor (≤200 percent of the Federal Poverty Level) and higher income beneficiaries without the LIS.

Data Sources/Study Setting

Medicare Advantage beneficiaries in 2008.

Study Design

We examined three drug cost responses using multivariate logistic regression: cost‐reducing behaviors (e.g., switching to generics), nonadherence (e.g., not refilling prescriptions), and financial stress (e.g., going without necessities).

Data Collection

Telephone interviews in a stratified random sample (N = 1,201, 70 percent response rate).

Principal Findings

After adjustment, a comparable percentage of unsubsidized near‐poor (26 percent) and higher income beneficiaries reported cost‐reducing behaviors (23 percent, p = .63); fewer LIS beneficiaries reported cost‐reducing behaviors (15 percent, p = .019 vs near‐poor). Unsubsidized near‐poor beneficiaries were more likely to reduce adherence (8.2 percent) than higher income (3.5 percent, p = .049) and LIS beneficiaries (3.1 percent, p = .027). Near‐poor beneficiaries also more frequently experienced financial stress due to drug costs (20 percent) than higher income beneficiaries (11 percent, p = .050) and LIS beneficiaries (11 percent, p = .015).

Conclusions

Low‐income subsidies provide protection from drug cost‐related nonadherence and financial stress. Beneficiaries just above the LIS income threshold are most at risk for these potentially adverse behaviors.
The Proportion of Work‐Related Emergency Department Visits Not Expected to Be Paid by Workers' Compensation: Implications for Occupational Health Surveillance, Research, Policy, and Health Equity
Authors: Groenewold Matthew R. , Baron Sherry L.
Published: May 2013

Objective

To examine trends in the proportion of work‐related emergency department visits not expected to be paid by workers' compensation during 2003–2006, and to identify demographic and clinical correlates of such visits.

Data Source

A total of 3,881 work‐related emergency department visit records drawn from the 2003–2006 National Hospital Ambulatory Medical Care Surveys.

Study Design

Secondary, cross‐sectional analyses of work‐related emergency department visit data were performed. Odds ratios and 95 percent confidence intervals were modeled using logistic regression.

Principal Findings

A substantial and increasing proportion of work‐related emergency department visits in the United States were not expected to be paid by workers' compensation. Private insurance, Medicaid, Medicare, and workers themselves were expected to pay for 40 percent of the work‐related emergency department visits with this percentage increasing annually. Work‐related visits by blacks, in the South, to for‐profit hospitals and for work‐related illnesses were all more likely not to be paid by workers' compensation.

Conclusions

Emergency department‐based surveillance and research that determine work‐relatedness on the basis of expected payment by workers' compensation systematically underestimate the occurrence of occupational illness and injury. This has important methodological and policy implications.
The Disparate Impact of the ACA‐Dependent Expansion across Population Subgroups
Authors: O'Hara Brett , Brault Matthew W.
Published: May 2013

Objective

This study presents evidence on how the dependent provision in the Affordable Care Act (ACA) differentially affected coverage for young adults across states and population subgroups.

Study Design/Methods/Data

The data derive from the American Community Survey. Using a difference‐in‐difference design, we compare the target population (ages 19–25) with a control group (ages 26–29).

Principal Findings

Net private health insurance coverage increased by 4.6 percentage points and overall coverage increased by 4.2 percentage points for people aged 19–25; more for Whites than non‐White subgroups.

Conclusions and Implications

Changes in coverage for states appear driven by demographics rather than the existence of prior dependent expansions by the state. Disparities in health care coverage remain, but the absolute level of coverage is improving.
Control of Postharvest Blue Mold of Nanfeng Mandarin by Application of Strain YS‐1 Paenibacillus brasilensis
Authors: Tu Qihong , Chen Jinyin , Guo Juanhua
Published: May 2013

In order to study its commercial value, antagonistic spectrum and storage application of YS‐1 Paenibacillus brasilensis were investigated in this paper. YS‐1 P. brasilensis showed obvious antifungal activity to 5 different fruit pathogens, which was of broad antagonistic spectrum. Effect and application of YS‐1 P. brasilensis fermentation liquid on Nanfeng mandarin at different storage temperatures were also investigated with the puncture inoculation method. Results showed that lesion diameter and disease incidence at 25 °C were higher than those at 5 °C after end of the storage, and there was significant difference between them. P. brasilensis fermentation liquid was effective for control of Penicillium italicum on Nanfeng mandarin stored at 5 °C for 25 d or 25 °C for 20 d. Preharvest treatment combined with postharvest treatment significantly reduced the decay rate of Nanfeng mandarin by 5.8% more than the control, particularly in the 1st 2 mo of storage. Fruits treated with P. brasilensis fermentation liquid in preharvest and postharvest period tended to have higher total sugar content, titratable acidity, ascorbic acid (AsA) content, and soluble solids content than those in the control group, and there was significant difference between the 2 groups. A delay was observed in the drop in AsA content. In this article, strain YS‐1 is reported for the 1st time as a biocontrol agent against blue mold of Nanfeng mandarin. The research will provide an application reference for preservation of citrus.
Nuclear mitochondrial pseudogenes in Austinograea alayseae hydrothermal vent crabs (Crustacea: Bythograeidae): effects on DNA barcoding
Authors: Kim Se‐Joo , Lee Kyeong Yong , Ju Se‐Jong
Published: May 2013

Members of the brachyuran crab family, Bythograeidae, are among the most abundant and common crabs in vent fields. However, their identification based on morphological characteristics often leads to incorrect species recognition due to a lack of taxonomic factors and the existence of sibling (or cryptic) species. For these reasons, we used DNA barcoding for vent crabs using mitochondrial cytochrome c oxidase subunit 1 (CO1). However, several nuclear mitochondrial pseudogenes (Numts) were amplified from Austinograea alayseae Guinot, 1990, using universal primers (Folmer primers). The Numts were characterized in six haplotypes, with 13.58–14.11% sequence divergence from A. alayseae, a higher nonsynonymous substitution ratio than true CO1, and the formation of an independent clade in bythograeids. In a neighbour‐joining tree, the origin of the Numts would be expected to incorporate into the nucleus at an ancestral node of Austinograea, and they mutated more slowly in the nucleus than CO1 in the mitochondria. This evolutionary process may have resulted in the higher binding affinity of Numts for the Folmer primers than CO1. In the present study, we performed long PCR for the amplification of CO1 in A. alayseae. We also present evidence that Numts can introduce serious ambiguity into DNA barcoding, including overestimating the number of species in bythograeids. These results may help in conducting taxonomic studies using mitochondrial genes from organisms living in hydrothermal vent fields.
Dissolved hydrogen and nitrogen fixation in the oligotrophic North Pacific Subtropical Gyre
Authors: Wilson Samuel T. , del Valle Daniela A. , Robidart Julie C. , Zehr Jonathan P. , Karl David M.
Published: May 2013

The production of hydrogen (H2) is an inherent component of biological dinitrogen (N2) fixation, and there have been several studies quantifying H2 production relative to N2 fixation in cultures of diazotrophs. However, conducting the relevant measurements for a field population is more complex as shown by this study of N2 fixation, H2 consumption and dissolved H2 concentrations in the oligotrophic North Pacific Ocean. Measurements of H2 oxidation revealed microbial consumption of H2 was equivalent to 1–7% of ethylene produced during the acetylene reduction assay and 11–63% of 15N2 assimilation on a molar scale. Varying abundances of Crocosphaera and Trichodesmium as revealed by nifH gene abundances broadly corresponded with diel changes observed in both N2 fixation and H2 oxidation. However, no corresponding changes were observed in the dissolved H2 concentrations which remained consistently supersaturated (147–560%) relative to atmospheric equilibrium. The results from this field study allow the efficiency of H2 cycling by natural populations of diazotrophs to be compared to cultured representatives. The findings indicate that dissolved H2 concentrations may depend not only on the community composition of diazotrophs but also upon relevant environmental parameters such as light intensity or the presence of other H2‐metabolizing microorganisms.
Alcohol‐selling outlets and mortality in Switzerland—the Swiss National Cohort
Authors: Spoerri Adrian , Zwahlen Marcel , Panczak Radoslaw , Egger Matthias , Huss Anke ,   Swiss National Cohort
Published: May 2013

Aim

To examine the association of alcohol‐related mortality and other causes of death with neighbourhood density of alcohol‐selling outlets for on‐site consumption.

Design, setting and participants

Longitudinal study of the adult Swiss population (n = 4 376 873) based on census records linked to mortality data from 2001 to 2008.

Measurements

Sex‐specific hazard ratios (HR) for death and 95% confidence intervals (95%CI) were calculated using Cox models adjusting for age, educational level, occupational attainment, marital status and other potential confounders. The density of alcohol‐selling outlets within 1000 m of the residence was calculated using geocodes of outlets and residences.

Findings

Compared with >17 outlets within 1000 m the HR for alcohol‐related mortality in men was 0.95 (95%CI: 0.89–1.02) for 8–17 outlets, 0.84 (95%CI: 0.77–0.90) for 3–7 outlets, 0.76 (95%CI: 0.68–0.83) for 1–2 outlets and 0.60 (95%CI: 0.51–0.72) for 0 outlets. The gradient in women was somewhat steeper, with a HR comparing 0 with >17 outlets of 0.39 (95%CI: 0.26–0.60). Mortality from mental and behavioural causes and lung cancer were also associated with density of alcohol‐selling outlets: HRs comparing 0 outlets with >17 outlets were 0.64 (95%CI: 0.52–0.79) and 0.79 (95%CI: 0.72–0.88), respectively, in men and 0.46 (95%CI: 0.27–0.78) and 0.63 (95%CI: 0.52–0.77), respectively, in women. There were weak associations in the same direction with all‐cause mortality in men but not in women.

Conclusions

In Switzerland, alcohol‐related mortality is associated with the density of outlets around the place of residence. Community‐level interventions to reduce alcohol outlet density may usefully complement existing interventions.
Efficacy of a combined nanoparticulate/calcium hydroxide root canal medication on elimination of Enterococcus faecalis
Authors: Javidi Maryam , Afkhami Farzaneh , Zarei Mina , Ghazvini Kiarash , Rajabi Omid
Published: May 2013

The purpose of this study was to evaluate the efficacy of Ca(OH)2 with or without a silver nanoparticle suspension to eliminate Enterococcus faecalis from root canals. A total of 66 extracted human single‐rooted teeth contaminated with E. faecalis were treated with 10% Ca(OH)2 alone, Ca(OH)2 with nanosilver or sterile water (as a negative control). Samples were obtained with paper points and Gates‐Glidden burs at 1 and 7 days after root canal preparation and the number of colony‐forming units (CFU) was determined. The number of CFUs observed after dressing with Ca(OH)2 + nanosilver was significantly less than the number observed with Ca(OH)2 alone after 1 or 7 days (P < 0.001, P < 0.001). No differences in antimicrobial properties were observed between the two time points in the Ca(OH)2 + nanosilver group (P > 0.05). Higher antimicrobial efficacy was observed in the Ca(OH)2 group after 7 days than 1 day (P < 0.001). This study highlighted the potential advantage of using a mixture of Ca(OH)2 and nanosilver for intracanal medicament.
Pressure changes during tracheal suctioning – a laboratory study
Authors: Palazzo S. G. C. , Soni B.
Published: May 2013

Suctioning is essential in managing tracheal tubes, but also has drawbacks. Using a bench model, we demonstrated the extent and time course of pressure changes during suctioning, examined their relationship with tracheal tube and catheter diameters and assessed the effects of artificial ‘sputum’ and of compensatory gas flow in the system. We suctioned at −20 kPa (−150 mmHg) and −80 kPa (−600 mmHg) using three different sized catheters and a 5.9‐mm diameter bronchoscope through tracheal tubes ranging from 6.5 mm to 9.0 mm in diameter. Pressure changes ranged from −0.1 kPa (−0.8 mmHg) to −20.4 kPa (−153.0 mmHg). We demonstrated more negative pressures with decreasing tracheal tube diameter (p = 0.024) and increasing catheter diameter (p = 0.038). Addition of artificial ‘sputum’ led to more negative, but unpredictable, pressures than those seen with clean tubes (p = 0.012). Bronchoscopic suctioning produced pressure changes even greater than the largest suction catheter (p = 0.0039). Using a closed system with continuous positive airway pressure and 155 l.min−1 compensatory gas flow attenuated the pressure changes generated both with a 4.0‐mm catheter (p = 0.0005) and on bronchoscopic suctioning (p = 0.0078). The time taken to reach 50% of minimum pressure was always less than 1 s. The use of high compensatory flows during suctioning merits clinical evaluation.
The Postal Sector as a Vector of Financial Inclusion
Authors: d'Alcantara G. , Gautier A.
Published: May 2013

Access to finance has become a major policy issue under the term Financial Inclusion. In this paper, we focus on the role of postal operators in financial inclusion policies. In developing countries, postal firms typically manage a dense network of counters with a unique coverage of rural areas where the banking sector is totally absent. We use a formal location model for postal counters and bank agencies to show that in rural areas a post‐bank partnership can be a vector of financial inclusion and that this can be done profitably.
The Impact of Price Regulation on the Cost of Capital
Authors: Camacho Fernando T. , Menezes Flavio M.
Published: May 2013

This paper investigates how price regulation under moral hazard can affect a regulated firm's cost of capital. We consider stylized versions of the two most typical regulatory frameworks that have been applied in the most recent decades by regulators: Price Cap and Cost of Service. We show that there is a trade‐off between lower operational costs and a higher cost of capital under Price Cap regulation and higher operational costs and a lower cost of capital under Cost of Service regulation. As a result, when the extent of moral hazard is not significant, Price Cap regulation generates lower welfare than does Cost of Service regulation.