bluuebunny/crossref_metadata_2025 huggingface dataset:
Ocular Surface APCs Are Necessary for Autoreactive T Cell-Mediated Experimental Autoimmune Lacrimal Keratoconjunctivitis
Authors: Schaumburg Chris S. , Siemasko Karyn F. , De Paiva Cintia S. , Wheeler Larry A. , Niederkorn Jerry Y. , Pflugfelder Stephen C. , Stern Michael E.
Published: September 2011

As specialized sentinels between the innate and adaptive immune response, APCs are essential for activation of Ag-specific lymphocytes, pathogen clearance, and generation of immunological memory. The process is tightly regulated; however, excessive or atypical stimuli may ignite activation of APCs in a way that allows self-Ag presentation to autoreactive T cells in the context of the necessary costimulatory signals, ultimately resulting in autoimmunity. Studies in both animal models and patients suggest that dry eye is a chronic CD4+ T cell-mediated ocular surface autoimmune-based inflammatory disease. Using a desiccating stress-induced mouse model of dry eye, we establish the fundamental role of APCs for both the generation and maintenance of ocular-specific autoreactive CD4+ T cells. Subconjunctival administration of liposome-encapsulated clodronate efficiently diminished resident ocular surface APCs, inhibited the generation of autoreactive CD4+ T cells, and blocked their ability to cause disease. APC-dependent CD4+ T cell activation required intact draining cervical lymph nodes, as cervical lymphadenectomy also inhibited CD4+ T cell-mediated dry eye disease. In addition, local depletion of peripheral conjunctival APCs blocked the ability of dry eye-specific CD4+ T cells to accumulate within the ocular surface tissues, suggesting that fully primed and targeted dry eye-specific CD4+ T cells require secondary activation by resident ocular surface APCs for maintenance and effector function. These data demonstrate that APCs are necessary for the initiation and development of experimental dry eye and support the standing hypothesis that dry eye is a self-Ag–driven autoimmune disease.
Outo-etnografie as selfhulp vir predikante met bedieningsmoegheid: Verkennende opmerkings
Authors: Brunsdon Alfred R. , Lotter George A.
Published: August 2011

Auto-ethnography as self-help for ministers with ministry-fatigue: Exploratory remarks This article addressed the possible benefits of auto-ethnography as a form of self-help for ministers suffering from ministry-fatigue. Given the fact that the ministry is a vocation with little or no support for its workers, ministers must develop self-help skills to manage fatigue. Auto-ethnography is an exciting new development in the field of qualitative research methodology. In recent times, a number of researchers have used this method to shed light on various phenomena, especially those of a personal nature. This article explored the notion that, apart from making a contribution to science, auto-ethnography also has therapeutic value for writers who implement this method. This article made some exploratory remarks on this issue, with special reference to the therapeutic possibilities that it may have for ministers suffering from ministry-fatigue.
Optimal Management of Severe/Refractory Asthma
Authors: Pakhale Smita , Mulpuru Sunita , Boyd Matthew
Published: September 2011

Asthma is a chronic inflammatory disease of the airways, affecting approximately 300 million people worldwide. Asthma results in airway hyperresponsiveness, leading to paroxysmal symptoms of wheeze, cough, shortness of breath, and chest tightness. When these symptoms remain uncontrolled, despite treatment with high doses of inhaled and ingested corticosteroids, asthmatic patients are predisposed to greater morbidity and require more health care support. Treating patients with severe asthma can be difficult and often poses a challenge to physicians when providing ongoing management. This clinical review aims to discuss the definition, prevalence and evaluation of severe asthmatics, and provides a review of the existing pharmacologic and non-pharmacologic treatment options.
Comparison Theorem for Conjugate Points of a Fourth-order Linear Differential Equation
Authors: Ben Amara Jamel
Published: August 2011

In 1961, J. Barrett showed that if the first conjugate point η(a) exists for the differential equation (r(x)y'')'' = p(x)y, where r(x) > 0 and p(x) > 0, then so does the first systems-conjugate point . The aim of this note is to extend this result to the general equation with middle term (q(x)y')' without further restriction on q(x), other than continuity.
Evolution of Eigenvalues along Rescaled Ricci Flow
Authors: Li Junfang
Published: August 2011

In this paper, we discuss monotonicity formulae of various entropy functionals under various rescaled versions of Ricci flow. As an application, we prove that the lowest eigenvalue of a family of geometric operators -4Δ+kR is monotonic along the normalized Ricci flow for all k≥1 provided the initial manifold has nonpositive total scalar curvature.
Does the Environment Moderate the Impact of a Mass Media Campaign to Promote Walking?
Authors: Gebel Klaus , Bauman Adrian E. , Reger-Nash Bill , Leyden Kevin M.
Published: September 2011

Purpose.

To examine if a mass media campaign influenced walking differently in people in different physical environments.

Design.

Quasi-experimental study.

Setting.

Wheeling, West Virginia.

Participants.

Random sample of adults age 50 to 65 years, response rate: 72.1% (n = 719 in intervention community, n = 753 in comparison community).

Intervention.

Mass media campaign.

Measures.

Self-reported measures were used in before and after telephone surveys for walking and the physical environment. Measures included 11 environmental walkability items, from which two subscales (i.e., usable sidewalks/aesthetics and facilities) were extracted.

Analysis.

Multiple linear regression.

Results.

Overall, walking increased by 2.7 minutes per week (standard deviation [SD] = 231.1, not significant [NS]). When confined to those insufficiently active at baseline (i.e., <30 minutes per day) the minutes walked increased by 92.1 minutes (SD = 152.9, p < .001). For the insufficiently active at baseline in the top half of the environmental factor of usable sidewalks, walking increased by 19 minutes more than in the bottom half (NS). For the factor of aesthetics and facilities, people in the more walkable environment increased walking by 87 minutes more than those in the bottom half (p < .001).

Conclusion.

In this community-wide physical activity, intervention changes in walking after the campaign were significantly moderated by some environmental attributes. This contributes to the limited evidence on the impact of the environment in enhancing community physical activity interventions. This finding needs to be replicated in other community interventions with greater environmental variation.
Digital Certification in the Brazilian Egovernment
Authors: Ferneda Edilson , Alonso Luiza Beth Nunes , Braga Lamartine Vieira
Published: September 2011

This article aims to analyze the role of digital certification in the development process of the electronic government actions in Brazil, as well to provide future perspectives. Qualitative research was done and the data gathering performed through semi-structured interviews. Ten nationally recognized stakeholders were interviewed either for the conceiving of public policies regarding electronic government as well for the implementation and inspection of related projects. The study demonstrates that digital certification is straightly connected with information security. Indirectly, the security that digital certification provides is the major condition for the development of the electronic government, once it can provide the bases for the improvement of internal process in Public Administration and the increase of public services and better quality for the interface between the State and the citizen.
The Significance of Management Information Systems for Enhancing Strategic and Tactical Planning
Authors: Karim Akram Jalal
Published: September 2011

Management Information Systems (MIS) is the key factor to facilitate and attain efficient decision making in an organization. This research explores the extent to which management information systems implemented to make successful decisions at two selected financial organizations. The research examined whether the selected financial institutions of Bahrain vary as to the use of Management Information Systems leadership of decision making for strategic and tactical planning purposes. The research adapted the quantitative research design to examine two research hypotheses. A total of 190 forms were equally distributed to those who are working at different management levels at the selected organizations. The results of the research showed that MIS was primarily used to enhance strategic planning in both financial institutions. The regression analysis revealed that Tactical planning is found to have no effect on Decision Making, while Strategic planning has a clear effect on the Decision Making Effectiveness in both organizations
A contribuição de Thomas Kuhn para a produção científica em administração
Authors: Walter Silvana Anita , Rocha Daniela Torres da
Published: August 2011

Este estudo objetiva analisar como os conceitos desenvolvidos por Kuhn, na obra A estrutura das revoluções científicas, têm e podem contribuir com os estudos da área de administração. Outro objetivo consiste em verificar se a área de administração emprega o termo paradigma conforme o sentido atribuído por Kuhn. Realizou-se uma pesquisa bibliográfica e bibliométrica nos estudos do EnANPAD, de 1997 a 2007. Observou-se, nos 66 estudos encontrados com citações de Kuhn (1962), que as áreas do EnANPAD que possuem mais artigos citando o autor são a de ensino e pesquisa e a de estudos organizacionais. Constatou-se que a maioria dos estudos revisados emprega o termo paradigma conforme o sentido atribuído por Kuhn (1962), e que os conceitos mais citados são: revolução científica, paradigma, fase pré-paradigmática e ciência normal. Identificou-se como tais conceitos estão contribuindo com a administração, principalmente no que se refere ao entendimento de características dessa área de estudo.
SOA, ERP II e competências organizacionais: traços de inovação na moderna gestão de TI
Authors: Biancolino César Augusto , Riccio Edson Luiz , Maccari Emerson Antônio
Published: August 2011

Este trabalho tem como objetivo avaliar qual é o papel das competências organizacionais que estão vinculadas ao universo de gestão da tecnologia SOA e dos sistemas ERPs no processo de sustentação do valor de uso destes aplicativos no cenário macroeconômico brasileiro, em sua perspectiva de pós-implementação. Para tal, utiliza o referencial teórico associado tanto à literatura voltada para o estudo das competências organizacionais como também à literatura voltada para o a gestão dos sistemas ERPs, com foco em sua perspectiva de principal ator da suíte de aplicativos associados à Tecnologia da Informação. A metodologia utilizada no estudo previu o desenvolvimento do método de estudo de casos múltiplos, através do qual as informações colhidas nas empresas foram analisadas em conjunto e de forma cruzada, possibilitando a identificação mais robusta das competências organizacionais e de suas respectivas aderências ao problema da pesquisa. As evidências empíricas sugerem que de fato existe um conjunto de competências organizacionais, especializada na gestão da área de TI envolvendo os aplicativos ERPs, inovação em TI e das tecnologias SOA e ERP II. Tem-se como conclusão que há três principais competências organizacionais ligadas aos sistemas ERP II que devem ser desenvolvidas pelas empresas de forma a maximizar o valor de uso desta tecnologia em função da competitividade e resultados organizacionais.
Administração e políticas públicas em educação: uma revisão sistemática da produção do EnANPAD e EnAPG de 1997 a 2009
Authors: Medeiros Mirna de Lima , Alves Thiago , Passador João Luiz , Passador Cláudia Souza
Published: August 2011

Diante do consenso sobre a importância da educação para o desenvolvimento econômico e social dos países, acredita-se que a administração das escolas e das organizações responsáveis pela gestão das redes de ensino é tema relevante para pesquisas em Administração. Nesse contexto, o objetivo deste artigo é descrever a contribuição do EnANPAD e do EnAPG para a produção de conhecimento sobre administração e políticas públicas da educação básica.Para isso foi realizada uma revisão sistemática nos anais destes eventos referentes ao período de 1997 a 2009. Foram analisados 49 artigos por meio de protocolo que permitiu descrever: características dos trabalhos (distribuição temporal das publicações e as características das autorias); aspectos metodológicos (abordagem e tipologia das pesquisas do ponto de vista acadêmico/científico); e temas abordados. Percebeu-se que a produção está distribuída heterogêneamente no tempo; os autores são em sua maioria vinculados a instituições do Sudeste e Sul do Brasil; há um equilíbrio entre estudos exploratórios e descritivos; e há poucos estudos inferênciais. A abordagem qualitativa é predominante (55%), contudo, há número representativo de trabalhos quantitativos (35%). Quanto aos temas, verificou-se que 81,6% dos artigos se referem a quatro temas principais: desigualdade socioeconômica, financiamento da educação, qualidade do ensino e instrumentos de gestão.
Contributions of primary and secondary biogenic VOC tototal OH reactivity during the CABINEX (Community Atmosphere-Biosphere INteractions Experiments)-09 field campaign
Authors: Kim S. , Guenther A. , Karl T. , Greenberg J.
Published: August 2011

Abstract. We present OH reactivity measurements using the comparative reactivity method with a branch enclosure technique for four different tree species (red oak, white pine, beech and red maple) in the UMBS PROPHET tower footprint during the Community Atmosphere Biosphere INteraction EXperiment (CABINEX) field campaign in July of 2009. Proton Transfer Reaction-Mass Spectrometry (PTR-MS) was sequentially used as a detector for OH reactivity and BVOC concentrations including isoprene and monoterpenes (MT) for enclosure air. Therefore, the measurement dataset contains both measured and calculated OH reactivity from well-known BVOC. The results indicate that isoprene and MT, and in one case a sesquiterpene, can account for the measured OH reactivity. Significant discrepancy between measured OH reactivity and calculated OH reactivity from isoprene and MT is found for the red maple enclosure dataset but it can be reconciled by adding reactivity from emission of a sesquiterpene, α-farnesene, detected by GC-MS. This leads us to conclude that no significant unknown BVOC emission contributed to ambient OH reactivity from these trees at least during the study period. However, this conclusion should be followed up by more comprehensive side-by-side intercomparison between measured and calculated OH reactivity and laboratory experiments with controlled temperature and light environments to verify effects of those essential parameters towards unknown/unmeasured reactive BVOC emissions. This conclusion leads us to explore the contribution towards ambient OH reactivity (the dominant OH sink in this ecosystem) oxidation products such as hydroxyacetone, glyoxal, methylglyoxal and C4 and C5-hydroxycarbonyl using recently published isoprene oxidation mechanisms (Mainz Isoprene Mechanism II and Leuven Isoprene Mechanism). Evaluation of conventionally unmeasured first generation oxidation products of isoprene and their possible contribution to ambient missing OH reactivity indicates that the ratio of OH reactivity from unmeasured products over OH reactivity from MVK + MACR is strongly dependent on NO concentrations. The unmeasured oxidation products can contribute ~7.2 % (8.8 % from LIM and 5.6 % by MIM 2 when NO = 100 pptv) of the isoprene contribution towards total ambient OH reactivity. This amount can explain ~8.0 % (9.7 % from LIM and 6.2 % from MIM 2) of missing OH reactivity, reported by Di Carlo et al. (2004) at the same site. Further study on the contribution from further generation of unmeasured oxidation products is needed to constrain tropospheric photochemical reactivity of BVOC that have important implications for both photochemical ozone and secondary organic aerosol formation.
Aerosol optical properties determined from sky-radiometer over Loess Plateau of Northwest China
Authors: Liu Y. , Huang J. , Shi G. , Takamura T. , Khatri P. , Bi J. , Shi J. , Wang T. , Wang X. , Zhang B.
Published: August 2011

Abstract. The aerosol optical properties and their associated radiative forcing are retrieved from sky-radiometer and surface solar radiation data collected over the Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL) for the period of March to May (MAM) 2009. The result shows that the seasonal mean aerosol optical depth (AOD) at 500 nm in MAM is 0.4. The single scattering albedo (SSA) at 500 nm in MAM at SACOL fluctuates significantly ranging from 0.82 to 0.97. The averaged value of SSA there for background aerosol is 0.92 in MAM, while it is smaller (0.89) during the dust event outbreak period. The smaller SSA can be interpreted as the result of larger particles during dust events. The averaged asymmetry factor (ASY) at 500 nm during dust event period is 0.81, which is much larger than 0.68 of background aerosols. The averaged shortwave radiative effect of the aerosols during dust event period in MAM is −6.25, −86.33 and 80.08 wm−2, respectively, at the top of the atmosphere (TOA), surface and in the atmosphere. The aerosols heat the atmosphere during dust event period by up to 2 K day−1 (daily averaged), which is 67 % larger than the heating (1.2 K day−1) of background aerosols. The significant heating effect in the atmosphere of the aerosols during dust event is determined by larger AOD and smaller SSA.
Time series of vegetation indices and the modifiable temporal unit problem
Authors: de Jong R. , de Bruin S.
Published: August 2011

Abstract. Time series of vegetation indices (VI) derived from satellite imagery provide a consistent monitoring system for terrestrial plant systems. They enable detection and quantification of gradual changes within the time frame covered, which are of crucial importance in global change studies, for example. However, VI time series typically contain a strong seasonal signal which complicates change detection. Commonly, trends are quantified using linear regression methods, while the effect of serial autocorrelation is remediated by temporal aggregation over bins having a fixed width. Aggregating the data in this way produces temporal units which are modifiable. Analogous to the well-known Modifiable Area Unit Problem (MAUP), the way in which these temporal units are defined may influence the fitted model parameters and therefore the amount of change detected. This paper illustrates the effect of this Modifiable Temporal Unit Problem (MTUP) on a synthetic data set and a real VI data set. Large variation in detected changes was found for aggregation over bins that mismatched full lengths of vegetative cycles, which demonstrates that aperiodicity in the data may influence model results. Using 26 yr of VI data and aggregation over full-length periods, deviations in VI gains of less than 1 % were found for annual periods, while deviations (with respect to seasonally adjusted data) increased up to 24 % for aggregation windows of 5 yr. This demonstrates that temporal aggregation needs to be carried out with care in order to avoid spurious model results.
Spatial and temporal connections in groundwater contribution to evaporation
Authors: Lam A. , Karssenberg D. , van den Hurk B. J. J. M. , Bierkens M. F. P.
Published: August 2011

Abstract. In climate models, lateral terrestrial water fluxes are usually neglected. We estimated the contribution of vertical and lateral groundwater fluxes to the land surface water budget at a subcontinental scale, by modeling convergence of groundwater and surfacewater fluxes. We present a hydrological model of the entire Danube Basin at 5 km resolution, and use it to show the importance of groundwater for the surface climate. Results show that the contribution of groundwater to evaporation is significant, and can locally be higher than 30 % in summer. We demonstrate through the same model that this contribution also has important temporal characteristics. A wet episode can influence groundwater contribution to summer evaporation for several years afterwards. This indicates that modeling groundwater flow has the potential to augment the multi-year memory of climate models. We also show that the groundwater contribution to evaporation is local by presenting the groundwater travel times and the magnitude of groundwater convergence. Throughout the Danube Basin the lateral fluxes of groundwater are negligible when modeling at this scale and resolution. This suggests that groundwater can be adequately added in land surface models by including a lower closed groundwater reservoir of sufficient size with two-way interaction with surface water and the overlying soil layers.
A simple and self-consistent geostrophic-force-balance model of the thermohaline circulation with boundary mixing
Authors: Callies J. , Marotzke J.
Published: August 2011

Abstract. A simple model of the thermohaline circulation (THC) is formulated, with the objective to represent explicitly the geostrophic force balance of the basinwide THC. The model comprises advective-diffusive density balances in two meridional-vertical planes located at the eastern and the western walls of a hemispheric sector basin. Boundary mixing constrains vertical motion to lateral boundary layers along these walls. Interior, along-boundary, and zonally integrated meridional flows are in thermal-wind balance. Rossby waves and the absence of interior mixing render isopycnals zonally flat except near the western boundary, constraining meridional flow to the western boundary layer. The model is forced by a prescribed meridional surface density profile. This two-plane model reproduces both steady-state density and steady-state THC structures of a primitive-equation model. The solution shows narrow deep sinking at the eastern high latitudes, distributed upwelling at both boundaries, and a western boundary current with poleward surface and equatorward deep flow. The overturning strength has a 2/3-power-law dependence on vertical diffusivity and a 1/3-power-law dependence on the imposed meridional surface density difference. Convective mixing plays an essential role in the two-plane model, ensuring that deep sinking is located at high latitudes. This role of convective mixing is consistent with that in three-dimensional models and marks a~sharp contrast with previous two-dimensional models. Overall, the two-plane model reproduces crucial features of the THC as simulated in simple-geometry three-dimensional models. At the same time, the model self-consistently makes quantitative a conceptual picture of the three-dimensional THC that hitherto has been expressed either purely qualitatively or not self-consistently.
Social‐aware delay tolerant networking for mobile‐to‐mobile file sharing
Authors: Palazzi Claudio E. , Bujari Armir
Published: August 2011

Peer‐to‐peer (P2P) overlay networks and mobile ad hoc networks share many key characteristics such as self‐organization and decentralization; they also face the crucial challenge of providing connectivity in a decentralized, dynamic environment. However, when considering ad hoc networks composed of mobile devices such as smartphones, we cannot rely on the continuous end‐to‐end path between peers as for classic Internet P2P applications; rather, we have to deal with low node density that creates mobile‐disconnected networks. Porting the P2P paradigm into mobile networks to create a mobile‐to‐mobile file sharing application will create a modern type of delay/disruption tolerant network. In this context, we discuss our new approach for P2P file sharing that considers networks composed of mobile smartphones. As an innovative feature, we leverage on peer mobility to reach data in other disconnected networks by implementing a delay/disruption tolerant network‐like store‐delegate‐and‐forward communication model, where a peer can delegate unaccomplished file download tasks to other peers. In order to increase the chances of eventually receiving the requested file while reducing the number of transmitted messages and data, social awareness is exploited by nodes to delegate unaccomplished tasks only to peers that are expected to be encountered again in the future. Copyright © 2011 John Wiley & Sons, Ltd.
EFFECT OF SANDY SEDIMENTS PRODUCED BY THE MECHANICAL CONTROL OF SAND DEPOSITION ON THE THERMAL REGIME OF UNDERLYING PERMAFROST ALONG THE QINGHAI‐TIBET RAILWAY
Authors: Xie s. , Qu J. , Zu R. , Zhang K. , Han Q. , Niu Q.
Published: August 2011

To date, the mechanical control of drifting sand is the main method used for the protection of the Qinghai‐Tibet Railway from damage. The thermal effect of sandy sediments which are held in place on the underlying permafrost is a key area of interest and the focus of this paper. A ground temperature investigation of the permafrost along the railway route was undertaken and results were related to the different mechanical control measures used to control moving sand which had resulted in varying sandy sediment thicknesses. The studies were conducted in the Hongliang River area of the Qinghai‐Tibet Plateau from June 2010 to September 2010 using thermistor sensors. The results showed that the permafrost ground temperature and its daily variation, as well as the thawing depth of the active layer, decreased after the setting‐up of sand movement controls which had resulted in the accumulation of thick sandy sediments within the outside fringe of sand‐control engineering, or a covering of thin sandy sediments within the inside trackside (fringe) of sand‐control engineering. Below the thick sandy sediment cover accumulated by sand‐blocking fences, the average maximum temperature decreased. Average temperature decreased and the average depth of seasonal thawing (average thinning) were 3·38°C, 0·54°C and 0·48 m, respectively. Below the thin sand sediment cover accumulated by the checkerboard sand barriers, the values for the same parameters were 1·02°C, 0·21°C and 0·5 m, respectively. This study found that the mechanical control of sand does not only protect the railway from obstruction, but also facilitates permafrost stability, which in turn can help promote safety in railway operations. Copyright © 2011 John Wiley & Sons, Ltd.
The alterations in hepatic microcirculation and Kupffer cell activity after biliary drainage in jaundiced mice
Authors: Okaya Tomohisa , Nakagawa Koji , Kimura Fumio , Shimizu Hiroaki , Yoshidome Hiroyuki , Ohtsuka Masayuki , Kato Atsushi , Yoshitomi Hideyuki , Ito Hiroshi , Miyazaki Masaru
Published: August 2011

Background/purpose

The aim of this study is to examine the effects of biliary drainage on hepatic microcirculation and Kupffer cell activity in the liver with obstructive jaundice.

Methods

Common bile duct ligation and division was performed on C57BL/6 mice to induce obstructive jaundice. Seven or 14 days after surgery, some mice underwent biliary drainage. Three days after biliary drainage, sinusoidal perfusion, leukocyte rolling and sticking in the postsinusoidal venules, and the diameters of sinusoids containing blood flow were evaluated using intravital microscopy. Kupffer cell phagocytic activity was estimated as the ratio of Kupffer cells that phagocytosed fluorescent‐labeled particles to sinusoids containing blood flow.

Results

Sinusoidal perfusion after biliary drainage was significantly increased compared with that in livers with obstructive jaundice, but remained decreased compared with controls. Although the number of rolling leukocytes and sticking leukocytes was significantly decreased, the diameters of sinusoids remained reduced, associated with an increase in Kupffer cell phagocytic activity compared with controls even after biliary drainage.

Conclusions

Leukocyte—endothelial cell interaction is ameliorated but sinusoids remain narrowed due to swelling of activated Kupffer cells; this might cause deterioration of hepatic microcirculation during the early phase of biliary drainage.
Endothelial dysfunction associated with obesity and the effect of weight loss interventions
Authors: Kerr S. M. P. , Livingstone M. B. E. , McCrorie T. A. , Wallace J. M. W.
Published: August 2011

Endothelial damage is central to the initiation and progression of atherosclerosis, while in addition vascular endothelial cells secrete several anti-atherogenic substances including the potent vasodilator nitric oxide. Increased adhesion molecule expression, in response to pathophysiological stimuli is perhaps the earliest indicator of compromised endothelial integrity. Obesity and adiposity are associated with an increased risk of CVD, influencing disease progression via a number of mechanisms, including enhanced endothelial activation. This review discusses possible mechanisms linking adiposity and more specifically regional fat depots with endothelial function and evaluates studies investigating the effect of weight loss on endothelial function, assessed by biochemical and physiological measurements. Overall, the research to date suggests that visceral adiposity is a stronger predictor of endothelial activation than overall adiposity, possibly mediated via the action of NEFA in circulation. While in general there is a suggestion that weight loss is associated with significant improvements in endothelial function, this is not apparent in all interventions and published literature to date provides less than convincing evidence for the effects of weight loss on endothelial activation.
Cerebral Oxygen Metabolism of Rats using Injectable 15O-Oxygen with a Steady-State Method
Authors: Kobayashi Masato , Mori Tetsuya , Kiyono Yasushi , Tiwari Vijay Narayan , Maruyama Rikiya , Kawai Keiichi , Okazawa Hidehiko
Published: August 2011

To develop a less-stressful and simple method for measurement of the cerebral metabolic rate of oxygen ( CMRO2) in small animals, the steady-state method was applied to injectable 15O2-PET (15O2-positron emission tomography) using hemoglobin-containing vesicles (15O2-HbV). Ten normal rats and 10 with middle cerebral arterial occlusion (MCAO) were studied using a small animal PET scanner. A series of 15O-PET scans with C15O-labeled HbV, H215O, and 15O2-HbV were performed with 10 to 15 minutes intervals to measure cerebral blood volume (CBV), cerebral blood flow (CBF), and CMRO2. Positron emission tomography scans were started with a tracer injection using a multiprogramming syringe pump, which provides a slowly increasing injection volume to achieve steady-state radioactivity for H215O and 15O2-HbV scans. The radioactivity concentration of 15O rapidly achieved equilibrium in the blood and whole brain at about 2 minutes after H215O and 15O2-HbV administration, which was stable during the scans. The whole brain mean values of CBF, CBV, and CMRO2 were 54.3 ± 2.0 mL per 100 g per minute, 4.9 ± 0.4 mL/100 g, and 2.8 ±0.2 μmoL per g per minute (6.2 ± 0.4 mL per 100 g per minute) in the normal rats, respectively. In the MCAO model rats, all hemodynamic parameters of the infarction area on the occlusion side significantly decreased. The steady-state method with 15O-labeled HbV is simple and useful to analyze hemodynamic changes in studies with model animals.
Resilience and Stuttering: Factors That Protect People From the Adversity of Chronic Stuttering
Authors: Craig Ashley , Blumgart Elaine , Tran Yvonne
Published: August 2011

Purpose

Chronic disorder can impose a significant negative mental health burden. This research was conducted to explore factors that may protect people from the adversity of chronic stuttering.

Method

The study employed a population group cohort design. Participants included 200 adults who have stuttered since childhood, and the sample was divided into those who were classified as resilient and nonresilient on the basis of their global psychopathology scores. Protective factor differences between the 2 groups were determined using multivariate analysis of variance and unique contributors to psychopathology were isolated using multiple regression.

Results

Factors that significantly distinguished between groups included superior levels of health status, social support, vitality and social functioning, fewer physical limitations, and a greater sense of self-efficacy. Three unique contributors to adaptive outcomes were found: self-efficacy, social support, and healthy social functioning.

Conclusions

A number of factors were isolated that potentially protect individuals with chronic stuttering from developing psychopathology. The findings provide a better understanding of how people cope with a chronic fluency disorder.
The stochastic Burgers equation with vorticity: Semiclassical asymptotic series solutions with applications
Authors: Neate Andrew , Reasons Scott , Truman Aubrey
Published: August 2011

We consider a stochastic Burgers type equation which incorporates a vector potential. The solution of this equation is not of gradient form and so this equation can be described as a stochastic Burgers equation with vorticity. Building on previous work on the standard stochastic Burgers equation, we discuss the related Hamilton-Jacobi theory in detail and show how to find semiclassical series expansions for our stochastic Burgers equation with vorticity. We examine the behaviour of the solution in the inviscid limit and discuss the geometric structure of the resulting singularities. We illustrate these results with an example of a Burgers type fluid in a rotating bucket under a harmonic oscillator potential. We conclude with a discussion of the relationship between the correspondence limit of Nelson's stochastic mechanics and stationary state solutions for Burgers equations and illustrate an example of the equations studied in this paper arising from considerations of the Coulomb potential.
Multilayer graphene nanoribbon under vertical electric field
Authors: Bala Kumar S. , Guo Jing
Published: August 2011

We study the effect of vertical electric-field (E-field) on the electronic properties of the multilayer armchair graphene nanoribbon (aGNR). Under E-field, the band structure of a bilayer aGNR undergoes interesting transformations, such as change in the electron velocity, sign of the electron effective mass, bandgap, and the position of the bandgap in the momentum space. Depending on the width of the aGNR and the applied E-field, the bandgap of the aGNR may either be increased or decreased. When the applied E-field is above a critical value, the bandgap of the bilayer aGNR is identical to that of the bilayer graphene, independent of the width. We also show that, for semiconducting multilayer aGNR with more than two layers, the bandgap decreases with increasing E-field, resulting in a semiconductor-to-metallic transition. This can be utilized to enhance the performance of graphene based transistor devices.
Effect of transverse magnetic field on laser produced plasma expansion into vacuum
Authors: Bennaceur-Doumaz D. , Djebli M.
Published: August 2011

A one-dimensional time-dependent magneto-hydrodynamic ideal model is used to investigate the dynamics of initially magnetized laser produced plasma expansion into vacuum, in the context of inertial fusion. The plasma is assumed to be fully ionized and in local thermodynamic equilibrium (LTE), allowing all charged particles to have the same temperatures. Self-similar solution shows that the density, velocity, and temperature increase with the strength of the magnetic field. The transverse magnetic field causes significant changes in the plasma expansion dynamics, including the plasma confinement. The plasma velocity increasing is also observed and the temperature is found to be larger compared to temperature in un-magnetized case.
Effects of anisotropic strain on perovskite LaMnO3+δ nanoparticles embedded in mesoporous silica
Authors: Tajiri T. , Saisho S. , Komorida Y. , Mito M. , Deguchi H. , Kohno A.
Published: August 2011

We applied anisotropic stress to LaMnO3+δ nanoparticles synthesized in one-dimensional pores of mesoporous silica and investigated the effects of the anisotropic strain on the nanoparticles, which consisted of ferromagnetic and antiferromagnetic particles. The nanoparticles in the one-dimensional pores were crushed without stress in the direction parallel to the silica walls that separated the pores when the mesoporous silica containing the nanoparticles is pressurized. X-ray diffraction patterns of the nanoparticles indicated that the lattice strain increased with increasing applied pressure. The lattice constants were found to reduce anisotropically, and the values saturated above a critical strain. Both the ferromagnetic and antiferromagnetic transition temperatures for the LaMnO3+δ nanoparticles initially increased with increasing pressure and then remained constant at around the critical strain. These results indicate that anisotropic stress causes distortion of the shape of nanoparticles. This induces an increase in the lattice strain and the anisotropic compression of the crystal structure, which, in turn, results in an increase in the transition temperatures.
Magnetic behavior of Fe(Se,Te) systems: First-principles calculations
Authors: Shi Hongliang , Huang Zhong-Bing , Tse John S. , Lin Hai-Qing
Published: August 2011

The magnetic behaviors in Fe(Se,Te) systems have been investigated systematically using density functional calculations. At the experimental lattice parameters, the ground state is found to be in the double stripe magnetic phase for FeTe but in the single stripe magnetic phase for FeSe and FeSe0.5Te0.5, and there is no preference in the different easy axes of magnetization. Substitution of Se by Te enlarges the size of the Fermi surface in FeSe0.5Te0.5, resulting in a stronger nesting effect and thus enhancing the superconductivity. It is found that the double stripe order in FeTe1-xSex changes to the single stripe order when x> 0.18. Spiral calculations on FeSe0.5Te0.5 show that the lowest energy is at the commensurate point Q→= (0.5,0.5), accompanied by additional local minima at two incommensurate points near Q→= (0.5,0.5). This observation is consistent with the experimentally observed positions of low energy magnetic excitations. Geometry optimization calculations show that the tetragonal cell relaxes to orthorhombic and monoclinic cells for FeSe and FeTe, respectively, but remains unchanged for FeSe0.5Te0.5.
Comparison of bulk and pitcher-catcher targets for laser-driven neutron production
Authors: Willingale L. , Petrov G. M. , Maksimchuk A. , Davis J. , Freeman R. R. , Joglekar A. S. , Matsuoka T. , Murphy C. D. , Ovchinnikov V. M. , Thomas A. G. R. , Van Woerkom L. , Krushelnick K.
Published: August 2011

Laser-driven d(d, n)-3He beam-target fusion neutron production from bulk deuterated plastic (CD) targets is compared with a pitcher-catcher target scheme using an identical laser and detector arrangement. For laser intensities in the range of (1–3) × 1019 W cm−2, it was found that the bulk targets produced a high yield (5 × 104 neutrons per steradian) beamed preferentially in the laser propagation direction. Numerical modeling shows the importance of considering the temperature adjusted stopping powers to correctly model the neutron production. The bulk CD targets have a high background target temperature leading to a reduced stopping power for the deuterons, which increases the probability of generating neutrons by fusion. Neutron production from the pitcher-catcher targets was not as efficient since it does not benefit from the reduced stopping power in the cold catcher target. Also, the inhibition of the deuteron acceleration by a proton rich contamination layer significantly reduces the pitcher-catcher neutron production.
Scanning magneto-optical Kerr microscope with auto-balanced detection scheme
Authors: Halahovets Y. , Siffalovic P. , Jergel M. , Senderak R. , Majkova E. , Luby S. , Kostic I. , Szymanski B. , Stobiecki F.
Published: August 2011

We have developed a scanning magneto-optical Kerr microscope dedicated to localization and measurement of the in-plane magnetization of ultra-thin layered magnetic nanostructures with high sensitivity and signal-to-noise ratio. The novel light detection scheme is based on a differential photodetector with automatic common mode noise rejection system with a high noise suppression up to 50 dB. The sensitivity of the developed detection scheme was tested by measurement of a single Co layer and a giant magnetoresistance (GMR) multilayer stack. The spatial resolution of the Kerr microscope was demonstrated by mapping an isolated 5×5 μm spin-valve pillar.
A microfluidics assisted porous silicon array for optical label-free biochemical sensing
Authors: Rea Ilaria , Orabona Emanuele , Lamberti Annalisa , Rendina Ivo , De Stefano Luca
Published: August 2011

A porous silicon (PSi) based microarray has been integrated with a microfluidic system, as a proof of concept device for the optical monitoring of selective label-free DNA-DNA interaction. A 4 × 4 square matrix of PSi one dimensional photonic crystals, each one of 200 μm diameter and spaced by 600 μm, has been sealed by a polydimethylsiloxane (PDMS) channels circuit. The PSi optical microarray elements have been functionalized by DNA single strands after sealing: the microfluidic circuit allows to reduce significantly the biologicals and chemicals consumption, and also the incubation time with respect to a not integrated device. Theoretical calculations, based on finite element method, taking into account molecular interactions, are in good agreement with the experimental results, and the developed numerical model can be used for device optimization. The functionalization process and the interaction between DNA probe and target has been monitored by spectroscopic reflectometry for each PSi element in the microchannels.
Effect of deposition parameters and semi-empirical relations between non-linear refractive index with linear refractive index and third order susceptibility for a-Ge20Se70-xIn10Bix thin films
Authors: Sharma Ishu , Tripathi S. K. , Barman P. B.
Published: August 2011

Present work reports the influence of deposition parameters, i.e., the effect of the type of substrate on the optical properties of a-Ge20Se70-xIn10Bix (x = 0, 2, 4, 6, 8, and 10) thin films. Optical constants were accurately determined by envelope method using transmission spectra in the wavelength region of 400–1800 nm. The order obtained for the refractive index is nmica > nmicroscope glass > nquartz for different substrates used in the deposition of thin films. The bandgap of the film deposited on mica substrate is smallest as compared to the bandgap of the films deposited on microscopic glass and quartz. To open the possibility of the use of chalcogenide glasses for non-linear switching, these vitreous systems were studied with respect to their non-linear susceptibility and refractive index. Third-order optical susceptibility (χ(3)) is evaluated from changes of index of refraction using Wang approximations. We examined the dependence of susceptibility on the absorption edge, thereby showing that the susceptibility rapidly increases with the redshift in absorption edge. Different formulations were used to predict the non-linear behavior of the Ge-Se-In-Bi system. The linear refractive index and Wemple-DiDomenico parameters were used for the determination of nonlinear refractive index in the wavelength region of 400 to 1800 nm. The addition of Bi drastically increases the non-linear refractive index. In amorphous materials, maximum optical non-linearity has been predicted at a telecommunication wavelength (∼1550 nm). Comparison of our results shows a good agreement with values available in the literature at 0.8 eV or 1550 nm. Non-linear refractive indices, three orders higher than silica glass, were obtained in the system under investigation. The obtained results may lead to yield more sensitive optical limiting devices, and these glasses may be used as an optical material for a high speed communication fiber.
Time dependence of interlayer coupling in Pd(50 Å)/Co(tCo Å)/Pd(54 Å)/Co(tCo Å)/Pd(50 Å) multilayer with perpendicular anisotropy
Authors: Wen F. S. , Zhang F. , Lü Y. F. , Xiang J. Y. , Li W. , Lu Y. F. , Liu Z. Y. , Xu B. , Yu D. L. , He J. L. , Tian Y. J.
Published: August 2011

Time-dependent ferromagnetic (FM)-antiferromagnetic (AFM) interlayer coupling transition has been found in Pd(50 Å)/Co(tCo Å)/Pd(54 Å)/Co(tCo Å)/Pd(50 Å) multilayer. During exposure to the air, saturation magnetic moment and coercivity both drop with time; moreover, a shift of the minor loop center for AFM coupling also decreases with time. During exposure of the sample to the air, as one possibility, the observed time-dependent FM-AFM interlayer coupling transition and decrease of AFM coupling strength may result from absorption of gaseous elements, which can induce reduction of Pd-polarization and a decrease of saturation magnetic moment; another possibility may be the alloying of the Co/Pd interface.
Misfit dislocation formation via pre-existing threading dislocation glide in (112¯2) semipolar heteroepitaxy
Authors: Hsu Po Shan , Young Erin C. , Romanov Alexey E. , Fujito Kenji , DenBaars Steven P. , Nakamura Shuji , Speck James S.
Published: August 2011

Cathodoluminescence (CL) was used to study the onset of mechanical stress relaxation in low indium composition semipolar (112¯2) InxGa1−xN lattice-mismatched layers grown on bulk GaN substrates. Monochromatic CL of short interfacial misfit dislocation (MD) segments showed a single threading dislocation (TD) associated with each MD segment—demonstrating that the initial stage of MD formation in semipolar III-nitride heterostructures proceeded by the bending and glide of pre-existing TDs on the (0001) slip plane. The state of coherency as determined by panchromatic CL is also compared to that determined by x-ray diffraction analysis based on crystallographic epilayer tilt and Matthew-Blakeslee’s critical thickness calculations.
Drag reduction of a miniature boat with superhydrophobic grille bottom
Authors: Jiang C. G. , Xin S. C. , Wu C. W.
Published: August 2011

Water strider can slide on water surface with a very small drag force using its long superhydrophobic legs. Inspired by the water strider legs, we report here a novel design of superhydrophobic grille structure for drag reduction. A miniature boat covered with a superhydrophobic grille at the bottom is fabricated and compared with a normal boat with flat bottom in the same size, and a significant drag reduction is obtained by the former. Experiments also reveal that the grille structure exhibits a remarkable loading capacity supplied by the water surface tension. It is found that the optimal design of such a miniature boat with a considerable loading capacity and a small drag can be realized through controlling the length and the spacing of the grilles. This study shows a new idea to reduce the fluid drag in microfluidics, micro electromechanical system and other engineering areas.