127 research outputs found

    Effect of topology on the collapse transition and the instantaneous shape of a model heteropolymer

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    The effect of topology on the collapse transition and instantaneous shape of an energy polydisperse polymer (a model heteropolymer) is studied by means of computer simulations. In particular, we consider three different chain topology, namely, linear (L), ring (R) and trefoil knot (T). The heteropolymer is modeled by assigning each monomer an interaction parameter, εi\varepsilon_i, drawn randomly from a Gaussian distribution. Through chain size scaling the transition temperature, θ\theta, is located and compared among the chains of different topogies. The influence of topology is reflected in the value of θ\theta and observed that θ(L)>θ(R)>θ(T)\theta(\text{L}) > \theta(\text{R}) > \theta(\text{T}) in a similar fashion to that of the homopolymer counterpart. Also studied chain size distributions, and the shape changes across the transition temperature characterised through shape parameters based on the eigenvalues of the gyration tensor. It is observed that, for the model heteropolymer, in addition to chain topology the θ\theta-temperature also depends on energy polydispersity.Comment: 10 pages, 9 figure

    Size polydisperse model Ionic Liquid in bulk

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    The static and the dynamic properties of a size-polydisperse model ionic liquid is studied using molecular dynamics simulations. Here, size of the anions is derived from a Gaussian distribution while keeping cation size fixed, resulting in a system that closely corresponds to IL mixtures with a common cation. We systematically explore the behavior of thermodynamic transition temperatures, spatial ordering of ions and the resulting screening behavior as a function of polydispersity index, δ\delta. We observe a non-monotonic dependence of transition temperatures on δ\delta, and this non-monotonic behaviour is also reflected in other properties such as screening length. Furthermore, from the radial distribution function analysis it is found that, upon varying δ\delta, the spatial ordering of cations is affected, while no such changes is seen for anion. On the other hand, the analysis of ion motion through mean-square displacement show that for all δ\delta values considered both inertial and diffusive regimes are observed (as expected in the liquid state). However, in contrast to neutral counterpart, the overall relaxation time of the polydisperse IL system increases (and hence decreasing diffusion coefficient) with increasing δ\delta.Comment: 9 pages, 8 figure

    Zolpidem dependence with frontal lobe syndrome: a case report

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    Zolpidem is a non-benzodiazepine sedative hypnotic that binds to the benzodiazepine binding site on the gammaaminobutyric acid type A (GABA-A) receptors. It is the most commonly prescribed sleep medication which has been shown to be effective for treating insomnia on a short-term basis with fewer side effects than traditional benzodiazepines, which are feared for their abuse and dependence potential. Many studies have reported efficacy and safety of zolpidem in treatment of insomnia keeping in mind about its low abuse, and dependence capability. We present a case of zolpidem dependence in a 36-year-old male to emphasize that zolpidem also should be judiciously prescribed under supervision so that it does not develop tolerance, abuse and dependence

    Consortium on Vulnerability to Externalizing Disorders and Addictions (cVEDA):A developmental cohort study protocol

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    Background: Low and middle-income countries like India with a large youth population experience a different environment from that of high-income countries. The Consortium on Vulnerability to Externalizing Disorders and Addictions (cVEDA), based in India, aims to examine environmental influences on genomic variations, neurodevelopmental trajectories and vulnerability to psychopathology, with a focus on externalizing disorders. Methods: cVEDA is a longitudinal cohort study, with planned missingness design for yearly follow-up. Participants have been recruited from multi-site tertiary care mental health settings, local communities, schools and colleges. 10,000 individuals between 6 and 23 years of age, of all genders, representing five geographically, ethnically, and socio-culturally distinct regions in India, and exposures to variations in early life adversity (psychosocial, nutritional, toxic exposures, slum-habitats, socio-political conflicts, urban/rural living, mental illness in the family) have been assessed using age-appropriate instruments to capture socio-demographic information, temperament, environmental exposures, parenting, psychiatric morbidity, and neuropsychological functioning. Blood/saliva and urine samples have been collected for genetic, epigenetic and toxicological (heavy metals, volatile organic compounds) studies. Structural (T1, T2, DTI) and functional (resting state fMRI) MRI brain scans have been performed on approximately 15% of the individuals. All data and biological samples are maintained in a databank and biobank, respectively. Discussion: The cVEDA has established the largest neurodevelopmental database in India, comparable to global datasets, with detailed environmental characterization. This should permit identification of environmental and genetic vulnerabilities to psychopathology within a developmental framework. Neuroimaging and neuropsychological data from this study are already yielding insights on brain growth and maturation patterns.</p

    Merchants of knowledge: Petty retail and differentiation without consolidation among farmers in Maharashtra, India

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    This article focuses on the intermediary figure of the village‐level petty retailer of chemical inputs, providing an account of the everyday relationships of farmers with transnational and domestic agribusiness capital. Retailers are figures from whom farmers purchase seeds, fertilizers, pesticides, and other chemicals. The article traces the rise of village‐level retailers in western Maharashtra, India, since the 1990s, and finds that Maratha (a dominant landholding cultivator caste) households have ventured into retailing. Further, farmers depend on retailers for credit, technical knowledge, and for the sale of their harvest. By analysing the pressures and risks of petty retail, visible in interactions with farmers, the article argues that even as retailing provides avenues for upward mobility to petty agricultural commodity producers, the trade is too volatile for the gains to sustain. Thus, the entry of Marathas into petty retail is akin to an attempt at class differentiation but without consolidation.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/144696/1/joac12249.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144696/2/joac12249_am.pd

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    The wages of whiteness in the absence of wages: racial capitalism, reactionary intercommunalism and the rise of Trumpism

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    In November 1970, Black Panther Party leader Huey P. Newton gave a lecture at Boston College where he introduced his theory of intercommunalism. Newton re-articulated Marxist theories of imperialism through the lens of the Black liberation struggle and argued that imperialism had entered a new phase called ‘reactionary intercommunalism’. Newton’s theory of intercommunalism o ers nothing less than a proto-theorisation of what we have come to call neo-liberal globalisation and its e ects on what W. E. B. Du Bois had seen as the racialisation of modern imperialism. Due to the initial historical dismissal of the Black Panther Party’s political legacy, Newton’s thought has largely been neglected for the past 40 years. This paper revisits Newton’s theory of intercommunalism, with the aim of achieving some form of epistemic justice for his thought, but also to highlight how Newton’s recasting of imperialism as reactionary intercommunalism provides critical insight into the rise of Trumpism in the US

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

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    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication
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