2D and 3D Dense-Fluid Shear Flows via Nonequilibrium Molecular Dynamics. Comparison of Time-and-Space-Averaged Tensor Temperature and Normal Stresses from Doll's, Sllod, and Boundary-Driven Shear Algorithms

Homogeneous shear flows (with constant strainrate du/dy) are generated with the Doll's and Sllod algorithms and compared to corresponding inhomogeneous boundary-driven flows. We use one-, two-, and three-dimensional smooth-particle weight functions for computing instantaneous spatial averages. The nonlinear stress differences are small, but significant, in both two and three space dimensions. In homogeneous systems the sign and magnitude of the shearplane stress difference, P(xx) - P(yy), depend on both the thermostat type and the chosen shearflow algorithm. The Doll's and Sllod algorithms predict opposite signs for this stress difference, with the Sllod approach definitely wrong, but somewhat closer to the (boundary-driven) truth. Neither of the homogeneous shear algorithms predicts the correct ordering of the kinetic temperatures, T(xx) > T(zz) > T(yy).Comment: 34 pages with 12 figures, under consideration by Physical Review

Microscopic and Macroscopic Stress with Gravitational and Rotational Forces

Many recent papers have questioned Irving and Kirkwood's atomistic expression for stress. In Irving and Kirkwood's approach both interatomic forces and atomic velocities contribute to stress. It is the velocity-dependent part that has been disputed. To help clarify this situation we investigate [1] a fluid in a gravitational field and [2] a steadily rotating solid. For both problems we choose conditions where the two stress contributions, potential and kinetic, are significant. The analytic force-balance solutions of both these problems agree very well with a smooth-particle interpretation of the atomistic Irving-Kirkwood stress tensor.Comment: Fifteen pages with seven figures, revised according to referees' suggestions at Physical Review E. See also Liu and Qiu's arXiv contribution 0810.080

The Trophic Life Cycle Stage of the Opportunistic Fungal Pathogen \u3cem\u3ePneumocystis murina\u3c/em\u3e Hinders the Ability of Dendritic Cells to Stimulate CD4\u3csup\u3e+\u3c/sup\u3e T Cell Responses

The life cycle of the opportunistic fungal pathogen Pneumocystis murina consists of a trophic stage and an ascus-like cystic stage. Infection with the cyst stage induces proinflammatory immune responses, while trophic forms suppress the cytokine response to multiple pathogen-associated molecular patterns (PAMPs), including β-glucan. A targeted gene expression assay was used to evaluate the dendritic cell response following stimulation with trophic forms alone, with a normal mixture of trophic forms and cysts, or with β-glucan. We demonstrate that stimulation with trophic forms downregulated the expression of multiple genes normally associated with the response to infection, including genes encoding transcription factors. Trophic forms also suppressed the expression of genes related to antigen processing and presentation, including the gene encoding the major histocompatibility complex (MHC) class II transactivator, CIITA. Stimulation of dendritic cells with trophic forms, but not a mixture of trophic forms and cysts, reduced the expression of MHC class II and the costimulatory molecule CD40 on the surface of the cells. These defects in the expression of MHC class II and costimulatory molecules corresponded with a reduced capacity for trophic form-loaded dendritic cells to stimulate CD4+ T cell proliferation and polarization. These data are consistent with the delayed innate and adaptive responses previously observed in immunocompetent mice inoculated with trophic forms compared to responses in mice inoculated with a mixture of trophic forms and cysts. We propose that trophic forms broadly inhibit the ability of dendritic cells to fulfill their role as antigen-presenting cells

Macrolide antibiotics for non-cystic fibrosis bronchiectasis

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To determine the impact of macrolide antibiotics in the treatment of adults and children with non-cystic fibrosis bronchiectasis

Report of the panel on the land surface: Process of change, section 5

The panel defined three main areas of study that are central to the Solid Earth Science (SES) program: climate interactions with the Earth's surface, tectonism as it affects the Earth's surface and climate, and human activities that modify the Earth's surface. Four foci of research are envisioned: process studies with an emphasis on modern processes in transitional areas; integrated studies with an emphasis on long term continental climate change; climate-tectonic interactions; and studies of human activities that modify the Earth's surface, with an emphasis on soil degradation. The panel concluded that there is a clear requirement for global coverage by high resolution stereoscopic images and a pressing need for global topographic data in support of studies of the land surface

TGF-β Isoform Specific Regulation of Airway Inflammation and Remodelling in a Murine Model of Asthma

The TGF-β family of mediators are thought to play important roles in the regulation of inflammation and airway remodelling in asthma. All three mammalian isoforms of TGF-β, TGF-β1–3, are expressed in the airways and TGF-β1 and -β2 are increased in asthma. However, there is little information on the specific roles of individual TGF-β isoforms. In this study we assess the roles of TGF-β1 and TGF-β2 in the regulation of allergen-induced airway inflammation and remodelling associated with asthma, using a validated murine model of ovalbumin sensitization and challenge, and isoform specific TGF-β neutralising antibodies. Antibodies to both isoforms inhibited TGF-β mediated Smad signalling. Anti-TGF-β1 and anti-TGF-β2 inhibited ovalbumin-induced sub-epithelial collagen deposition but anti-TGF-β1 also specifically regulated airway and fibroblast decorin deposition by TGF-β1. Neither antibody affected the allergen-induced increase in sub-epithelial fibroblast-like cells. Anti- TGF-β1 also specifically inhibited ovalbumin-induced increases in monocyte/macrophage recruitment. Whereas, both TGF-β1 and TGF-β2 were involved in regulating allergen-induced increases in eosinophil and lymphocyte numbers. These data show that TGF-β1 and TGF-β2 exhibit a combination of specific and shared roles in the regulation of allergen-induced airway inflammation and remodelling. They also provide evidence in support of the potential for therapeutic regulation of specific subsets of cells and extracellular matrix proteins associated with inflammation and remodelling in airway diseases such as asthma and COPD, as well as other fibroproliferative diseases

Father absence and trajectories of offspring mental health across adolescence and young adulthood:Findings from a UK-birth cohort

Background High prevalence of parental separation and resulting biological father absence raises important questions regarding its impact on offspring mental health across the life course. We specifically examined whether these relationships vary by sex and the timing of exposure to father absence (early or middle childhood). Methods This study is based on up to 8409 children from the Avon Longitudinal Study of Parents and Children (ALSPAC). Participants provided self-reports of depression (Clinical Interview Schedule-Revised) at age 24 years and depressive symptoms (Short Mood and Feelings Questionnaire) between the ages of 10 and 24 years. Biological father absence in childhood was assessed through maternal questionnaires at regular intervals from birth to 10 years. We estimated the association between biological father absence and trajectories of depressive symptoms using multilevel growth-curve modelling. Results Early but not middle childhood father absence was strongly associated with increased odds of offspring depression and greater depressive symptoms at age 24 years. Early childhood father absence was associated with higher trajectories of depressive symptoms during adolescence and early adulthood compared with father presence. Differences in the level of depressive symptoms between middle childhood father absent and father present groups narrowed into adulthood. Limitations This study could be biased by attrition and residual confounding. Conclusions We found evidence that father absence in childhood is persistently associated with offspring depression in adolescence and early adulthood. This relationship varies by sex and timing of father's departure, with early childhood father absence emerging as the strongest risk factor for adverse offspring mental health trajectories Further research is needed to identify mechanisms that could inform preventative interventions to reduce the risk of depression in children who experience father absence

Country differences in the diagnosis and management of coronary heart disease : a comparison between the US, the UK and Germany

Background The way patients with coronary heart disease (CHD) are treated is partly determined by non-medical factors. There is a solid body of evidence that patient and physician characteristics influence doctors' management decisions. Relatively little is known about the role of structural issues in the decision making process. This study focuses on the question whether doctors' diagnostic and therapeutic decisions are influenced by the health care system in which they take place. This non-medical determinant of medical decision-making was investigated in an international research project in the US, the UK and Germany. Methods Videotaped patients within an experimental study design were used. Experienced actors played the role of patients with symptoms of CHD. Several alternative versions were taped featuring the same script with patients of different sex, age and social status. The videotapes were shown to 384 randomly selected primary care physicians in the three countries under study. The sample was stratified on gender and duration of professional experience. Physicians were asked how they would diagnose and manage the patient after watching the video vignette using a questionnaire with standardised and open-ended questions. Results Results show only small differences in decision making between British and American physicians in essential aspects of care. About 90% of the UK and US doctors identified CHD as one of the possible diagnoses. Further similarities were found in test ordering and lifestyle advice. Some differences between the US and UK were found in the certainty of the diagnoses, prescribed medications and referral behaviour. There are numerous significant differences between Germany and the other two countries. German physicians would ask fewer questions, they would order fewer tests, prescribe fewer medications and give less lifestyle advice. Conclusion Although all physicians in the three countries under study were presented exactly the same patient, some disparities in the diagnostic and patient management decisions were evident. Since other possible influences on doctors treatment decisions are controlled within the experimental design, characteristics of the health care system seem to be a crucial factor within the decision making process

Band Merging of Spitzer Detections in the SWIRE Fields

The Spitzer Wide-area Infra-Red Extragalactic (SWIRE) Survey has imaged 49 deg^2 of high-Galactic-latitude sky in seven infrared bands spanning wavelengths from 3.6 μm to 160 μm, with beam sizes ranging from about 2″ to 40″. Lists of extracted sources from the individual bands are merged using the Spitzer band merging software. Positions and their uncertainties are used to identify possible band-to-band matches, then decision theory is applied to choose a best match. We present our assessment of band merging reliability based on analysis of the random match rate, and we discuss our application of constraints of multi-band detections and proximity to produce reliable catalogs. We examine the crucial role played by positional uncertainties for extractions made with SExtractor and with Spitzer's Astronomical Point-source EXtraction (APEX) software

The global pandemic has shown we need an action plan for the ocean

The COVID-19 pandemic is the first serious test of how science can inform decision-making in the face of an immediate global threat, yielding important lessons on how science, society and policy interact. The global societal and economic impact of COVID-19 has shown that we need to assess, plan and prepare for potential future changes. These insights are particularly important for the ocean science community because of the global connectivity of the ocean and its crucial role in the Earth's climate system and in supporting all life on Earth. With climate change already impacting society and ecosystems, implementing mitigation measures to avoid and reduce emissions of greenhouses gases is an immediate priority (IPCC, 2021). Irreversible changes are already underway in the oceans and their impacts over the coming decades will continue to affect human communities, requiring societal responses and adaptation across multiple scales (IPCC, 2019, 2021)