594 research outputs found

    Computational modelling of solvent effects in a prolific solvatomorphic porous organic cage

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    Crystal structure prediction methods can enable the in silico design of functional molecular crystals, but solvent effects can have a major influence on relative lattice energies sometimes thwarting predictions. This is particularly true for porous solids, where solvent included in the pores can have an important energetic contribution. Here we present a Monte Carlo solvent insertion procedure for predicting the solvent filling of porous structures from crystal structure prediction landscapes, tested using a highly solvatomorphic porous organic cage molecule, CC1. We use this method to rationalise the fact that the predicted global energy minimum structure for CC1 is never observed from solvent crystallisation. We also explain the formation of three different solvatomorphs of CC1 from three structurally-similar chlorinated solvents. Calculated solvent stabilisation energies are found to correlate with experimental results from thermogravimetric analysis, suggesting a future computational framework for a priori materials design that includes solvation effects

    Marine Biodiversity in South Africa: An Evaluation of Current States of Knowledge

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    Continental South Africa has a coastline of some 3,650 km and an Exclusive Economic Zone (EEZ) of just over 1 million km2. Waters in the EEZ extend to a depth of 5,700 m, with more than 65% deeper than 2,000 m. Despite its status as a developing nation, South Africa has a relatively strong history of marine taxonomic research and maintains comprehensive and well-curated museum collections totaling over 291,000 records. Over 3 million locality records from more than 23,000 species have been lodged in the regional AfrOBIS (African Ocean Biogeographic Information System) data center (which stores data from a wider African region). A large number of regional guides to the marine fauna and flora are also available and are listed

    Safety and Immunogenicity of H5N1 Influenza Vaccine Based on Baculovirus Surface Display System of Bombyx mori

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    Avian influenza virus (H5N1) has caused serious infections in human beings. This virus has the potential to emerge as a pandemic threat in humans. Effective vaccines against H5N1 virus are needed. A recombinant Bombyx mori baculovirus, Bmg64HA, was constructed for the expression of HA protein of H5N1 influenza virus displaying on the viral envelope surface. The HA protein accounted for approximately 3% of the total viral proteins in silkworm pupae infected with the recombinant virus. Using a series of separation and purification methods, pure Bmgp64HA virus was isolated from these silkworm pupae bioreactors. Aluminum hydroxide adjuvant was used for an H5N1 influenza vaccine. Immunization with this vaccine at doses of 2 mg/kg and 0.67 mg/kg was carried out to induce the production of neutralizing antibodies, which protected monkeys against influenza virus infection. At these doses, the vaccine induced 1:40 antibody titers in 50% and 67% of the monkeys, respectively. The results of safety evaluation indicated that the vaccine did not cause any toxicity at the dosage as large as 3.2 mg/kg in cynomolgus monkeys and 1.6 mg/kg in mice. The results of dose safety evaluation of vaccine indicated that the safe dose of the vaccine were higher than 0.375 mg/kg in rats and 3.2 mg/kg in cynomolgus monkeys. Our work showed the vaccine may be a candidate for a highly effective, cheap, and safe influenza vaccine for use in humans

    The fate of steroid estrogens: Partitioning during wastewater treatment and onto river sediments

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    This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2010 Springer Science+Business Media B.V.The partitioning of steroid estrogens in wastewater treatment and receiving waters is likely to influence their discharge to, and persistence in, the environment. This study investigated the partitioning behaviour of steroid estrogens in both laboratory and field studies. Partitioning onto activated sludge from laboratory-scale Husmann units was rapid with equilibrium achieved after 1 h. Sorption isotherms and Kd values decreased in the order 17α-ethinyl estradiol > 17α-estradiol > estrone > estriol without a sorption limit being achieved (1/n >1). Samples from a wastewater treatment works indicated no accumulation of steroid estrogens in solids from primary or secondary biological treatment, however, a range of steroid estrogens were identified in sediment samples from the River Thames. This would indicate that partitioning in the environment may play a role in the long-term fate of estrogens, with an indication that they will be recalcitrant in anaerobic conditions.EPSR

    The politics of regulatory enforcement and compliance: Theorizing and operationalizing political influences

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    There is broad consensus in the literature on regulatory enforcement and compliance that politics matters. However, there is little scholarly convergence on what politics is or rigorous theorization and empirical testing of how politics matters. Many enforcement and compliance studies omit political variables altogether. Among those that address political influences on regulatory outcomes, politics has been defined in myriad ways and, too often, left undefined. Even when political constructs are explicitly operationalized, the mechanisms by which they influence regulatory outcomes are thinly hypothesized or simply ignored. If politics is truly as important to enforcement and compliance outcomes as everyone in the field seems to agree, regulatory scholarship must make a more sustained and systematic effort to understand their relationship, because overlooking this connection risks missing what is actually driving regulatory outcomes. This article examines how the construct of “politics” has been conceptualized in regulatory theory and analyzes how it has been operationalized in empirical studies of regulatory enforcement and compliance outcomes. It brings together scholarship across disciplines that rarely speak but have much to say to one another on this subject in order to constitute a field around the politics of regulation. The goal is to sharpen theoretical and empirical understandings of when and how regulation works by better accounting for the role politics plays in its enforcement

    Ultraviolet radiation shapes seaweed communities

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    The Prevalence of the Term Subluxation in Chiropractic Degree Program Curricula Throughout the World

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    Background: The subluxation construct generates debate within and outside the profession. The International Chiropractic Education Collaboration, comprised of 10 chiropractic programs outside of North America, stated they will only teach subluxation in a historical context. This research sought to determine how many chiropractic institutions worldwide still use the term in their curricula and to expand upon the previous work of Mirtz & and Perle. Methods: Forty-six chiropractic programs, 18 United States (US) and 28 non-US, were identified from the World Federation of Chiropractic Educational Institutions list. Websites were searched by multiple researchers for curricular information September 2016–September 2017. Some data were not available on line, so email requests were made for additional information. Two institutions provided additional information. The total number of mentions of subluxation in course titles, technique course (Tech) descriptions, principles and practice (PP) descriptions, and other course descriptions were reported separately for US and non-US institutions. Means for each category were calculated. The number of course titles and descriptions using subluxation was divided by the total number of courses for each institution and reported as percentages. Results: Means for use of subluxation by US institutions were: Total course titles = .44; Tech = 3.83; PP = 1.50; other = 1.16. For non-US institutions, means were: Total course titles = .07; Tech = .27; PP = .44; other = 0. The mean total number of mentions was 6.94 in US vs. 0.83 in non-US institutions. Similarly, the mean course descriptions was 6.50 in US vs. 0.72 in non-US institutions. Conclusions: The term subluxation was found in all but two US course catalogues. The use of subluxation in US courses rose from a mean of 5.53 in 2011 to 6.50 in 2017. US institutions use the term significantly more frequently than non-US. Possible reasons for this were discussed. Unscientific terms and concepts should have no place in modern education, except perhaps in historical context. Unless these outdated concepts are rejected, the chiropractic profession and individual chiropractors will likely continue to face difficulties integrating with established health care systems and attaining cultural authority as experts in conservative neuro-musculoskeletal health care.https://doi.org/10.1186/s12998-018-0191-

    High resolution 3-Dimensional imaging of the human cardiac conduction system from microanatomy to mathematical modeling

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    Cardiac arrhythmias and conduction disturbances are accompanied by structural remodelling of the specialised cardiomyocytes known collectively as the cardiac conduction system. Here, using contrast enhanced micro-computed tomography, we present, in attitudinally appropriate fashion, the first 3-dimensional representations of the cardiac conduction system within the intact human heart. We show that cardiomyocyte orientation can be extracted from these datasets at spatial resolutions approaching the single cell. These data show that commonly accepted anatomical representations are oversimplified. We have incorporated the high-resolution anatomical data into mathematical simulations of cardiac electrical depolarisation. The data presented should have multidisciplinary impact. Since the rate of depolarisation is dictated by cardiac microstructure, and the precise orientation of the cardiomyocytes, our data should improve the fidelity of mathematical models. By showing the precise 3-dimensional relationships between the cardiac conduction system and surrounding structures, we provide new insights relevant to valvar replacement surgery and ablation therapies. We also offer a practical method for investigation of remodelling in disease, and thus, virtual pathology and archiving. Such data presented as 3D images or 3D printed models, will inform discussions between medical teams and their patients, and aid the education of medical and surgical trainees

    Interoceptive hypersensitivity and interoceptive exposure in patients with panic disorder: specificity and effectiveness

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    BACKGROUND: Interoceptive exposure has been validated as an effective component of cognitive behavioral therapy (CBT) for the treatment of panic disorder but has hitherto received little research attention. We examined the effectiveness of various interoceptive exposure exercises using the Body Sensations Questionnaire (BSQ) (Chambless et al., 1984). METHODS: We first performed an exploratory principal factor analysis of all the items contained in the BSQ to obtain meaningful dimensions of interoceptive fears. Next, we examined the correlations between each interoceptive exposure task's degree of similarity to panic attacks and each BSQ factor and then examined whether the BSQ factor scores decreased in comparison with the baseline values when the corresponding exposure tasks were successfully completed by the subjects. RESULTS: The factor analyses revealed four factors, which we named "pseudoneurological fears", "gastrointestinal fears", "cardiorespiratory fears" and "fears of dissociative feelings." Among the nine interoceptive exposure tasks, 'hyperventilation', 'shaking head', 'holding breath' and 'chest breathing' were considered to reproduce pseudoneurological symptoms, 'breathing through a straw' was considered to reproduce gastrointestinal symptoms, and 'spinning' was considered to reproduce both pseudoneurological and dissociative symptoms; none of the interoceptive exercises were found to reproduce cardiorespiratory symptoms. Among each group of patients for whom 'hyperventilation', 'holding breath', 'spinning' or 'chest breathing' was effective, a significant improvement in the BSQ pseudoneurological fears factor scores was observed. On the other hand, no significant difference between the baseline and endpoint values of the BSQ gastrointestinal fears or the BSQ fears of dissociative feelings factor scores were observed among the patients for whom 'spinning' or 'breathing through a straw' was effective. CONCLUSION: Several interoceptive exposure tasks were particularly effective in reducing pseudoneurological fears. New interoceptive tasks, especially tasks related to cardiorespiratory and dissociative feelings, are needed

    Prevalence and Factors Associated with Intestinal Parasitic Infection among Children in an Urban Slum of Karachi

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    Background:Intestinal parasitic infections are endemic worldwide and have been described as constituting the greatest single worldwide cause of illness and disease. Poverty, illiteracy, poor hygiene, lack of access to potable water and hot and humid tropical climate are the factors associated with intestinal parasitic infections. The study aimed to estimate prevalence and identify factors associated with intestinal parasitic infections among 1 to 5 years old children residing in an urban slum of Karachi Pakistan. Methods And PrincipalFindings:A cross sectional survey was conducted from February to June 2006 in Ghosia Colony Gulshan Town Karachi, Pakistan. A simple random sample of 350 children aged 1-5 years was collected. The study used structured pre-tested questionnaire, anthropometric tools and stool tests to obtain epidemiological and disease data. Data were analyzed using appropriate descriptive, univariate and multivariable logistic regression methods. The mean age of participants was 2.8 years and 53% were male. The proportions of wasted, stunted and underweight children were 10.4%, 58.9% and 32.7% respectively. The prevalence of Intestinal parasitic infections was estimated to be 52.8% (95% CI: 46.1, 59.4). Giardia lamblia was the most common parasite followed by Ascaris lumbricoides, Blastocystis hominis and Hymenolepis nana. About 43% children were infected with single parasite and 10% with multiple parasites. Age {Adjusted Odds Ratio (aOR) = 1.5, 95% CI: 1.1, 1.9}, living in rented households (aOR = 2.0, 95% CI: 1.0, 3.9) and history of excessive crying (aOR = 1.9, 95% CI: 1.0, 3.4) were significantly associated with intestinal parasitic infections.Conclusion:Intestinal parasites are highly prevalent in this setting and poverty was implicated as an important risk factor for infection. Effective poverty reduction programmes and promotion of deworming could reduce intestinal parasite carriage. There is a need for mass scale campaigns to create awareness about health and hygiene
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