Superrotation in Terrestrial Atmospheres

Atmospheric superrotation with prograde equatorial winds and an equatorial angular momentum maximum is ubiquitous in planetary atmospheres. It is clear that eddy fluxes of angular momentum toward the equator are necessary to generate it. But under what conditions superrotation arises has remained unclear. This paper presents simulations and a scaling theory that establish conditions under which superrotation occurs in terrestrial atmospheres. Whether superrotation arises depends on the relative importance of factors that favor or disfavor superrotation. Convection preferentially generates Rossby waves near the equator, where the Rossby number is O(1). Since the Rossby waves transport angular momentum toward their source regions, this favors superrotation. Meridional temperature gradients preferentially lead to baroclinic instability and wave generation away from the equator. Eddy transport of angular momentum toward the baroclinic source region implies transport out of low latitudes, which disfavors superrotation. Simulations with an idealized GCM show that superrotation tends to arise when the equatorial convective generation of wave activity and its associated eddy angular momentum flux convergence exceed the baroclinic eddy angular momentum flux divergence. Convective and baroclinic wave activity generation is related through scaling arguments to mean-flow properties, such as planetary rotation rates and meridional temperature gradients. The scaling arguments show, for example, that superrotation is favored when the off-equatorial baroclinicity and planetary rotation rates are low, as they are, for example, on Venus. Similarly, superrotation is favored when the convective heating strengthens, which may account for the superrotation seen in extreme global warming simulations

Principle and design of pseudo-natural products

Natural products (NPs) are a significant source of inspiration towards the discovery of new bioactive compounds based on novel molecular scaffolds. However, there are currently only a small number of guiding synthetic strategies available to generate novel NP-inspired scaffolds, limiting both the number and types of compounds accessible. In this Perspective, we discuss a design approach for the preparation of biologically relevant small-molecule libraries, harnessing the unprecedented combination of NP-derived fragments as an overarching strategy for the synthesis of new bioactive compounds. These novel ‘pseudo-natural product’ classes retain the biological relevance of NPs, yet exhibit structures and bioactivities not accessible to nature or through the use of existing design strategies. We also analyse selected pseudo-NP libraries using chemoinformatic tools, to assess their molecular shape diversity and properties. To facilitate the exploration of biologically relevant chemical space, we identify design principles and connectivity patterns that would provide access to unprecedented pseudo-NP classes, offering new opportunities for bioactive small-molecule discovery

Discovery of 2,4-dimethoxypyridines as novel autophagy inhibitors

© 2018 Elsevier Ltd Autophagy is a catabolic process, which mediates degradation of cellular components and has important roles in health and disease. Therefore, small molecule modulators of autophagy are in great demand. Herein, we describe a phenotypic high-content screen for autophagy inhibitors, which led to the discovery of a dimethoxypyridine-based class of autophagy inhibitors, which derive from previously reported, natural product-inspired MAP4K4 inhibitors. Comprehensive structure-activity relationship studies led to a potent compound, and biological validation experiments indicated that the mode of action was upstream or independent of mTOR

Dyslipidemia and Food Security in Low-Income US Adolescents: National Health and Nutrition Examination Survey, 2003-2010.

INTRODUCTION: Low levels of food security are associated with dyslipidemia and chronic disease in adults, particularly in women. There is a gap in knowledge about the relationship between food security among youth and dyslipidemia and chronic disease. We investigated the relationship between food security status and dyslipidemia among low-income adolescents. METHODS: We analyzed data from adolescents aged 12 to 18 years (N = 1,072) from households with incomes at or below 200% of the federal poverty level from the National Health and Nutrition Examination Survey (NHANES) 2003-2010. We used logistic regression to examine the relationship between household food security status and the odds of having abnormalities with fasting total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), serum triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), TG/HDL-C ratio, and apolipoprotein B (Apo B). Models included age, sex, race/ethnicity, smoking status, partnered status in the household, and maternal education, with additional adjustment for adiposity. RESULTS: Household food security status was not associated with elevated TC or LDL-C. Adolescents with marginal food security were more likely than food-secure peers to have elevated TGs (odds ratio [OR] = 1.86; 95% confidence interval [CI], 1.14-3.05), TG/HDL-C ratio (OR = 1.74; 95% CI, 1.11-2.82), and Apo B (OR = 1.98; 95% CI, 1.17-3.36). Female adolescents with marginal food security had greater odds than male adolescents of having low HDL-C (OR = 2.69; 95% CI, 1.14-6.37). No elevated odds of dyslipidemia were found for adolescents with low or very low food security. Adjustment for adiposity did not attenuate estimates. CONCLUSION: In this nationally representative sample, low-income adolescents living in households with marginal food security had increased odds of having a pattern consistent with atherogenic dyslipidemia, which represents a cardiometabolic burden above their risk from adiposity alone

Effects of a Mindfulness-Based Intervention on Distress, Weight Gain, and Glucose Control for Pregnant Low-Income Women: A Quasi-Experimental Trial Using the ORBIT Model.

BackgroundStress can lead to excessive weight gain. Mindfulness-based stress reduction that incorporates mindful eating shows promise for reducing stress, overeating, and improving glucose control. No interventions have tested mindfulness training with a focus on healthy eating and weight gain during pregnancy, a period of common excessive weight gain. Here, we test the effectiveness of such an intervention, the Mindful Moms Training (MMT), on perceived stress, eating behaviors, and gestational weight gain in a high-risk sample of low income women with overweight/obesity.MethodWe conducted a quasi-experimental study assigning 115 pregnant women to MMT for 8 weeks and comparing them to 105 sociodemographically and weight equivalent pregnant women receiving treatment as usual. Our main outcomes included weight gain (primary outcome), perceived stress, and depression.ResultsWomen in MMT showed significant reductions in perceived stress (β = - 0.16) and depressive symptoms (β = - 0.21) compared to the treatment as usual (TAU) control group. Consistent with national norms, the majority of women (68%) gained excessive weight according to Institute of Medicine weight-gain categories, regardless of group. Slightly more women in the MMT group gained below the recommendation. Among secondary outcomes, women in MMT reported increased physical activity (β = 0.26) and had lower glucose post-oral glucose tolerance test (β = - 0.23), being 66% less likely to have impaired glucose tolerance, compared to the TAU group.ConclusionA short-term intervention led to significant improvements in stress, and showed promise for preventing glucose intolerance. However, the majority of women gained excessive weight. A longer more intensive intervention may be needed for this high-risk population. Clinical Trials.gov #NCT01307683

Pseudo Natural Products—Chemical Evolution of Natural Product Structure

Pseudo‐natural products (PNPs) combine natural product (NP) fragments in novel arrangements not accessible by current biosynthesis pathways. As such they can be regarded as non‐biogenic fusions of NP‐derived fragments. They inherit key biological characteristics of the guiding natural product, such as chemical and physiological properties, yet define small molecule chemotypes with unprecedented or unexpected bioactivity. We iterate the design principles underpinning PNP scaffolds and highlight their syntheses and biological investigations. We provide a cheminformatic analysis of PNP collections assessing their molecular properties and shape diversity. We propose and discuss how the iterative analysis of NP structure, design, synthesis, and biological evaluation of PNPs can be regarded as a human‐driven branch of the evolution of natural products, that is, a chemical evolution of natural product structure

Theoretical calculations of N 2-broadened half-widths of n 5

N 2 -broadening Temperature dependence of half-width Vibrational and rotational state dependence a b s t r a c t A number of satellite instruments are measuring nitric acid, HNO 3 , in the Earth's atmosphere. In order to do retrievals of temperature and concentration profiles, the spectral parameters for many thousands of HNO 3 transitions must be known. Currently the HITRAN database uses a constant estimated value for the air-broadened half-width of HNO 3 . To help improve the line shape parameters, complex Robert-Bonamy calculations were made to determine N 2 -broadened half-widths for some 5000 transitions of HNO 3 in the n 5 band. The intermolecular potential is a sum of electrostatic terms (dipole-quadrupole and quadrupole-quadrupole) and the atom-atom potential expanded to eighth order. The trajectory parameters were adjusted to yield better agreement with measurement. Velocity integrated calculations were made at seven temperatures in order to determine the temperature dependence of the half-widths. The half-width data are compared with available rotation band measurements. The average percent difference between the measured and calculated half-widths is À2.38 for N 2 -broadening and À0.65 for air-broadening. The temperature, vibrational, and rotational state dependence of the half-width are investigated

Perceptions of the Community Food Environment and Related Influences on Food Choice Among Midlife Women Residing in Rural and Urban Areas: A Qualitative Analysis

Introduction—Qualitative research on food choice has rarely focused on individuals’ perceptions of the community food environment. Women remain gatekeepers of the family diet and food purchasing. Therefore we assessed midlife, Southern women's perceptions of the food environment. Related influences on food choices at work and at home were also examined. Methods—We recruited 28 low- and moderate-income, midlife (37-67 years) women from rural and urban areas of southeastern North Carolina, using typical case and snowball sampling. They responded to questions about multilevel influences on food choice in semi-structured, in-depth interviews. Results—Women perceived differences between urban and rural food environments, with rural areas having fewer supermarkets and fast food restaurants compared to urban areas, which had fewer produce stands. Workplace food choices were affected by the social environment (co-workers), personal health concerns, and the surrounding food environment. Food chosen at home was primarily influenced by family members, health concerns, and convenient food sources. Discussion—While future studies should explore findings in more representative populations, potential intervention strategies can be inferred, including emphasizing healthful aspects of the food environment. Intervention and advocacy efforts are needed to improve aspects of the food environment that make healthy choices difficult. Originally published in Women & Health Vol. 49, No. 2-3, 2009

The vulnerability of public spaces: challenges for UK hospitals under the 'new' terrorist threat

This article considers the challenges for hospitals in the United Kingdom that arise from the threats of mass-casualty terrorism. Whilst much has been written about the role of health care as a rescuer in terrorist attacks and other mass-casualty crises, little has been written about health care as a victim within a mass-emergency setting. Yet, health care is a key component of any nation's contingency planning and an erosion of its capabilities would have a significant impact on the generation of a wider crisis following a mass-casualty event. This article seeks to highlight the nature of the challenges facing elements of UK health care, with a focus on hospitals both as essential contingency responders under the United Kingdom's civil contingencies legislation and as potential victims of terrorism. It seeks to explore the potential gaps that exist between the task demands facing hospitals and the vulnerabilities that exist within them