Computer simulation study of the nematic–vapour interface in the Gay–Berne model

We present computer simulations of the vapour–nematic interface of the Gay–Berne model. We considered situations which correspond to either prolate or oblate molecules. We determine the anchoring of the nematic phase and correlate it with the intermolecular potential parameters. On the other hand, we evaluate the surface tension associated to this interface. We find a corresponding states law for the surface tension dependence on the temperature, valid for both prolate and oblate molecules.Fundación Portuguesa para la Ciencia y la Tecnología EXCL / FIS-NAN / 0083/2012Ministerio de Economía y Competitividad FIS2012-32455Junta de Andalucía P09-FQM-493

Numerical study of surface-induced reorientation and smectic layering in a nematic liquid crystal

Surface-induced profiles of both nematic and smectic order parameters in a nematic liquid crystal, ranging from an orienting substrate to "infinity", were evaluated numerically on base of an extended Landau theory. In order to obtain a smooth behavior of the solutions at "infinity" a boundary energy functional was derived by linearizing the Landau energy around its equilibrium solutions. We find that the intrinsic wave number of the smectic structure, which plays the role of a coupling between nematic and smectic order, strongly influences the director reorientation. Whereas the smectic order is rapidly decaying when moving away from the surface, the uniaxial nematic order parameter shows an oscillatory behavior close to the substrate, accompanied by a non-zero local biaxiality.Comment: LaTeX, 17 pages, with 4 postscript figure

Localization criteria for Anderson models on locally finite graphs

We prove spectral and dynamical localization for Anderson models on locally finite graphs using the fractional moment method. Our theorems extend earlier results on localization for the Anderson model on \ZZ^d. We establish geometric assumptions for the underlying graph such that localization can be proven in the case of sufficiently large disorder

Dynamic properties of liquid Ni revisited

Liquid Ni has previously been studied by different approaches such as molecular dynamics simulations and experimental techniques including inelastic neutron and X-ray scattering. Although some puzzling results, such as the shape of the sound dispersion curve for q ≤ 1.0 Å−1, have already been sorted out, there still persist some discrepancies, among different studies, for greater q-values. We have performed ab initio simulation calculations which show how those differences can be reconciled. Moreover, we have found that the transverse current spectral functions have some features which, so far, had previously been shown by high pressure liquid metals

Potential common radiation problems for components and diagnostics in future magnetic and inertial confinement fusion devices

This work aims at identifying common potential problems that future fusion devices will encounter for both magnetic (MC) and inertial (IC) confinement approaches in order to promote joint efforts and to avoid duplication of research

Impact of Public Housing Relocations: Are Changes in Neighborhood Conditions Related to STIs Among Relocaters?

Cross-sectional and ecologic studies suggest that place characteristics influence sexual behaviors and sexually-transmitted infections (STIs). Using data from a predominately substance-misusing cohort of African-American adults relocating from US public housing complexes, this multilevel longitudinal study tested the hypothesis that participants who experienced greater post-relocation improvements in neighborhood conditions (i.e., socioeconomic disadvantage, social disorder, STI prevalence, male:female sex ratios) would have reduced odds of testing positive for an STI over time

Female Genital Mutilation: perceptions of healthcare professionals and the perspective of the migrant families

<p>Abstract</p> <p>Background</p> <p>Female Genital Mutilation (FGM) is a traditional practice which is harmful to health and is profoundly rooted in many Sub-Saharan African countries. It is estimated that between 100 and 140 million women around the world have been victims of some form of FGM and that each year 3 million girls are at risk of being submitted to these practices. As a consequence of the migratory phenomena, the problems associated with FGM have extended to the Western countries receiving the immigrants. The practice of FGM has repercussions on the physical, psychic, sexual and reproductive health of women, severely deteriorating their current and future quality of life. Primary healthcare professionals are in a privileged position to detect and prevent these situations of risk which will be increasingly more present in Spain.</p> <p>Methods/Design</p> <p>The objective of the study is to describe the knowledge, attitudes and practices of the primary healthcare professionals, working in 25 health care centres in Barcelona and Girona regions, regarding FGM, as well as to investigate the perception of this subject among the migrant communities from countries with strong roots in these practices. A transversal descriptive study will be performed with a questionnaire to primary healthcare professionals and migrant healthcare users.</p> <p>Using a questionnaire specifically designed for this study, we will evaluate the knowledge, attitudes and skills of the healthcare professionals to approach this problem. In a sub-study, performed with a similar methodology but with the participation of cultural mediators, the perceptions of the migrant families in relation to their position and expectancies in view of the result of preventive interventions will be determined.</p> <p>Variables related to the socio-demographic aspects, knowledge of FGM (types, cultural origin, geographic distribution and ethnicity), evaluation of attitudes and beliefs towards FGM and previous contact or experience with cases or risk situations will be obtained.</p> <p>Discussion</p> <p>Knowledge of these harmful practices and a preventive approach from a transcultural perspective may represent a positive intervention model for integrative care of immigrants, respecting their values and culture while also being effective in eliminating the physical and psychic consequences of FGM.</p

Recent Advancements in the LC- and GC-Based Analysis of Malondialdehyde (MDA): A Brief Overview

Malondialdehyde (MDA) is an end-product of lipid peroxidation and a side product of thromboxane A2 synthesis. Moreover, it is not only a frequently measured biomarker of oxidative stress, but its high reactivity and toxicity underline the fact that this molecule is more than “just” a biomarker. Additionally, MDA was proven to be a mutagenic substance. Having said this, it is evident that there is a major interest in the highly selective and sensitive analysis of this molecule in various matrices. In this review, we will provide a brief overview of the most recent developments and techniques for the liquid chromatography (LC) and gas chromatography (GC)-based analysis of MDA in different matrices. While the 2-thiobarbituric acid assay still is the most prominent methodology for determining MDA, several advanced techniques have evolved, including GC–MS(MS), LC–MS(MS) as well as several derivatization-based strategies

Real-world effectiveness of caplacizumab vs the standard of care in immune thrombotic thrombocytopenic purpura

Immune thrombotic thrombocytopenic purpura (iTTP) is a thrombotic microangiopathy caused by anti-ADAMTS13 antibodies. Caplacizumab is approved for adults with an acute episode of iTTP in conjunction with plasma exchange (PEX) and immunosuppression. The objective of this study was to analyze and compare the safety and efficacy of caplacizumab vs the standard of care and assess the effect of the concomitant use of rituximab. A retrospective study from the Spanish TTP Registry of patients treated with caplacizumab vs those who did not receive it was conducted. A total of 155 patients with iTTP (77 caplacizumab, 78 no caplacizumab) were included. Patients initially treated with caplacizumab had fewer exacerbations (4.5% vs 20.5%; P <.05) and less refractoriness (4.5% vs 14.1%; P <.05) than those who were not treated. Time to clinical response was shorter when caplacizumab was used as initial treatment vs caplacizumab used after refractoriness or exacerbation. The multivariate analysis showed that its use in the first 3 days after PEX was associated with a lower number of PEX (odds ratio, 7.5; CI, 2.3-12.7; P <.05) and days of hospitalization (odds ratio, 11.2; CI, 5.6-16.9; P <.001) compared with standard therapy. There was no difference in time to clinical remission in patients treated with caplacizumab compared with the use of rituximab. No severe adverse event was described in the caplacizumab group. In summary, caplacizumab reduced exacerbations and refractoriness compared with standard of care regimens. When administered within the first 3 days after PEX, it also provided a faster clinical response, reducing hospitalization time and the need for PEX

A Protective Role for ELR+ Chemokines during Acute Viral Encephalomyelitis

The functional role of ELR-positive CXC chemokines in host defense during acute viral-induced encephalomyelitis was determined. Inoculation of the neurotropic JHM strain of mouse hepatitis virus (JHMV) into the central nervous system (CNS) of mice resulted in the rapid mobilization of PMNs expressing the chemokine receptor CXCR2 into the blood. Migration of PMNs to the CNS coincided with increased expression of transcripts specific for the CXCR2 ELR-positive chemokine ligands CXCL1, CXCL2, and CXCL5 within the brain. Treatment of JHMV-infected mice with anti-CXCR2 blocking antibody reduced PMN trafficking into the CNS by >95%, dampened MMP-9 activity, and abrogated blood-brain-barrier (BBB) breakdown. Correspondingly, CXCR2 neutralization resulted in diminished infiltration of virus-specific T cells, an inability to control viral replication within the brain, and 100% mortality. Blocking CXCR2 signaling did not impair the generation of virus-specific T cells, indicating that CXCR2 is not required to tailor anti-JHMV T cell responses. Evaluation of mice in which CXCR2 is genetically silenced (CXCR2−/− mice) confirmed that PMNs neither expressed CXCR2 nor migrated in response to ligands CXCL1, CXCL2, or CXCL5 in an in vitro chemotaxis assay. Moreover, JHMV infection of CXCR2−/− mice resulted in an approximate 60% reduction of PMN migration into the CNS, yet these mice survived infection and controlled viral replication within the brain. Treatment of JHMV-infected CXCR2−/− mice with anti-CXCR2 antibody did not modulate PMN migration nor alter viral clearance or mortality, indicating the existence of compensatory mechanisms that facilitate sufficient migration of PMNs into the CNS in the absence of CXCR2. Collectively, these findings highlight a previously unappreciated role for ELR-positive chemokines in enhancing host defense during acute viral infections of the CNS