12 research outputs found

    Topological flat bands in strained graphene: substrate engineering and optical control

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    The discovery of correlated phases in twisted moir\'e superlattices accelerated the search for low-dimensional materials with exotic properties. A promising approach uses engineered substrates to strain the material. However, designing substrates for tailored properties is hindered by the incomplete understanding of the relationship between substrate's shapes and electronic properties of the deposited materials. By analyzing effective models of graphene under periodic deformations with generic crystalline profiles, we identify strong C2zC_{2z} symmetry breaking as the critical substrate geometric feature for emerging energy gaps and quasi-flat bands. We find continuous strain profiles producing connected pseudo-magnetic field landscapes are important for band topology. We show that the resultant electronic and topological properties from a substrate can be controlled with circularly polarized light, which also offers unique signatures for identifying the band topology imprinted by strain. Our results can guide experiments on strain engineering for exploring interesting transport and topological phenomena.Comment: Title changed, second part replaced by new contents. Supporting information will be freely available from the website of Nano Letter

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Data-Augmentation for Bangla-English Code-Mixed Sentiment Analysis: Enhancing Cross Linguistic Contextual Understanding

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    In today&#x2019;s digital world, automated sentiment analysis from online reviews can contribute to a wide variety of decision-making processes. One example is examining typical perceptions of a product based on customer feedbacks to have a better understanding of consumer expectations, which can help enhance everything from customer service to product offerings. Online review comments, on the other hand, frequently mix different languages, use non-native scripts and do not adhere to strict grammar norms. For a low-resource language like Bangla, the lack of annotated code-mixed data makes automated sentiment analysis more challenging. To address this, we collect online reviews of different products and construct an annotated Bangla-English code mix (BE-CM) dataset (Dataset and other resources are available at https://github.com/fokhruli/CM-seti-anlysis). On our sentiment corpus, we also compare several alternative models from the existing literature. We present a simple but effective data augmentation method that can be utilized with existing word embedding algorithms without the need for a parallel corpus to improve cross-lingual contextual understanding. Our experimental results suggest that training word embedding models (e.g., Word2vec, FastText) with our data augmentation strategy can help the model in capturing the cross-lingual relationship for code-mixed sentences, thereby improving the overall performance of existing classifiers in both supervised learning and zero-shot cross-lingual adaptability. With extensive experimentations, we found that XGBoost with Fasttext embedding trained on our proposed data augmentation method outperforms other alternative models in automated sentiment analysis on code-mixed Bangla-English dataset, with a weighted F1 score of 87&#x0025;

    Prevalence and multidrug-resistant pattern of Salmonella from the eggs and egg-storing trays of retail markets of Bangladesh

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    Aim: Salmonellosis is one of the most common and widely distributed foodborne illnesses in human, and multidrugresistance of Salmonella spp. has increased in developing countries with the indiscriminate use of antibiotics in the poultry production system. A cross-sectional study was conducted on randomly selected retail markets of Chittagong City Corporation to determine the prevalence and antimicrobial resistance pattern of Salmonella isolated from commercial layer eggs, eggshell surface, and egg-storing trays. Materials and Methods: Chicken eggs, egg surface, and egg-storing trays samples from the retail markets were collected for isolating Salmonella spp. (bacteriological culture methods) followed by antimicrobial susceptibility testing (disc diffusion method) against Salmonella isolates during the period from July to December 2013. Results: Out of the 310 layer eggs, egg surface, and egg-storing trays samples, the highest prevalence of Salmonella spp. was found in eggs trays (57.15%) and the lowest (13.33%) in eggs and the prevalence differed significantly (p0.05). Isolated Salmonella was tested for resistance to eight different antimicrobial agents, using disc diffusion method. Among eight antimicrobial tested (n=111), 100% resistance were found to ampicillin and amoxicillin followed by erythromycin (60-100%), tetracycline (72-93%), ciprofloxacin (22-66%), colistin (27-66%), enrofloxacin (42-54%), and pefloxacin 23.07% across the study sites. Ciprofloxacin remained sensitive in 40.9% cases and, pefloxacin and colistin appeared to be almost sensitive (61-72%) against Salmonella isolates at studied areas. Salmonella isolates showed multidrug-resistance pattern up to five of the eight antimicrobials tested. Conclusion: It can be said that the rational use of antibiotics needs to be adopted in commercial poultry farming system of Bangladesh to prevent the emergence of drug-resistance Salmonella to protect the public health consequences

    Occurrence of diseases and disease conditions in cattle and goats at the Upazilla Veterinary Hospital, Debidwar, Comilla

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    Objective: A significant number of animals enrolled at UVH regularly from surrounding villages for treating their sick animals, de-worming, vaccination purposes. Therefore, a study was done to define the occurrence of common diseases and disease conditions in cattle and goats at the Upazilla Veterinary Hospital, Debidwar under Comilla district. Materials and methods: Data on various diseases were collected from the record book of hospital during April 2016 to March 2017. The total number of animals were 889, among which cattle were 637 (71.65%) and goats were 252 (28.35%). The presumptive diagnosis was performed based on general examination, physical examination, and clinical examination of animals, and microscopic examination based on common laboratory techniques. Results: Based on clinical examinations, 14 different types of diseases and disease conditions were detected. In cattle (N=637; 71.65%), where FMD (14.44%, n=92), mastitis (6.59%, n=42), digestive disorders (19%, n=121), respiratory disorders (6.12%, n=39), parasitic infestations such as mixed infestation of both ecto- and endo-parasites (34.22%, n=218), acidosis (1.88%, n=12), myiasis (6.12%, n=39), corneal opacity (1.57%, n=10), protozoal diseases (1.26%, n=8), BQ (2.20%, n=14), milk fever (0.94%, n=6), reproductive disorders (4.87%, n=31) and others (0.75%, n=5) were detected. Age wise prevalence in young and adult were (38.62%, n=246) and (61.38%, n=391), respectively. Moreover, sex wise prevalence in male and female were (34.85%, n=222) and (65.15%, n=415) respectively. In goat, (N= 252; 28.35%) 11 different types of diseases and disease conditions such as PPR (12.30%, n=31), mastitis (2.38%, n=6), digestive disorders (19.84%, n=50), parasitic infestation (29.76%, n=75), respiratory disorders (15.08, n=38), myiasis (11.11%, n=28), corneal opacity (4.76%, n=12), acidosis (1.98%, n=5) protozoal diseases such as babesiosis, anaplasmosis (0.79%, n=2) and reproductive disorders (1.59%, n=4), correspondingly. Sex wise prevalence in male and female goat were (44.05%, n=111) and (55.95%, n=141), respectively. Conclusion: All the diseases and disease conditionswere recorded more or less frequently among all age group of cattle and goats though some of the specific diseases and disease conditionshad specific age and species susceptibility such as black quarter in young cattle and PPR in young goats, respectively. A comprehensive updated data with the total population record of that area and proper analysis is needed to identify the actual level of disease and disease conditions in UVH. [J Adv Vet Anim Res 2018; 5(2.000): 117-122

    Fast-food and obesity: Status among the younger population in Bangladesh

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    Increasing rate of fast-food consumption has been associated with different health related concerns (e.g., obesity, heart disease). This study aimed to determine the prevalence of fast-food consumption among young adult students in Chittagong, Bangladesh, and to assess the correlation of fast-food consumption with obesity. A total of 440 youth was included using a systemic random sampling from universities and colleges in Chittagong in order to perform a cross-sectional analysis. The students who reported frequent fast-food consumption (1–3 times per week) accounted for 30.5% (n=134) of the sample, while 32.5% (n=143) of participants reported consuming fast-food 8–15 times per month. There was a significant (p=0.030) difference between students who consumed and did not consume fast-food. Youth who reported consuming fast-food and soft drinks more than 4 times per week constituted 35.0% (n=154), followed by approximately 27.7% (n=122) who consumed these items 1–3 times per week. In addition, an obesity epidemic was observed among those who reported low levels of physical exercise or lack of sleep. The study illustrates that Bangladeshi youth face an increasing risk of becoming overweight and obese. Prevention is regarded as the most effective way to reduce the prevalence of obesity

    Fast-food and obesity: Status among the younger population in Bangladesh

    No full text
    Increasing rate of fast-food consumption has been associated with different health related concerns (e.g., obesity, heart disease). This study aimed to determine the prevalence of fast-food consumption among young adult students in Chittagong, Bangladesh, and to assess the correlation of fast-food consumption with obesity. A total of 440 youth was included using a systemic random sampling from universities and colleges in Chittagong in order to perform a cross-sectional analysis. The students who reported frequent fast-food consumption (1–3 times per week) accounted for 30.5% (n=134) of the sample, while 32.5% (n=143) of participants reported consuming fast-food 8–15 times per month. There was a significant (p=0.030) difference between students who consumed and did not consume fast-food. Youth who reported consuming fast-food and soft drinks more than 4 times per week constituted 35.0% (n=154), followed by approximately 27.7% (n=122) who consumed these items 1–3 times per week. In addition, an obesity epidemic was observed among those who reported low levels of physical exercise or lack of sleep. The study illustrates that Bangladeshi youth face an increasing risk of becoming overweight and obese. Prevention is regarded as the most effective way to reduce the prevalence of obesity

    Drug repurposing approach against novel Coronavirus disease (COVID-19) through virtual screening targeting SARS-CoV-2 main protease

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    Novel coronavirus disease (COVID-19) was identified from China in December 2019 and spread rapidly through human-to-human transmission, affecting so many people worldwide. Until now, there has been no specific treatment against the disease and repurposing of the drug. Our investigation aimed to screen potential inhibitors against coronavirus for the repurposing of drugs. Our study analyzed sequence comparison among SARS-CoV, SARS-CoV-2, and MERS-CoV to determine the identity matrix using discovery studio. SARS-CoV-2 Mpro was targeted to generate an E-pharmacophore hypothesis to screen drugs from the DrugBank database having similar features. Promising drugs were used for docking-based virtual screening at several precisions. Best hits from virtual screening were subjected to MM/GBSA analysis to evaluate binding free energy, followed by the analysis of binding interactions. Furthermore, the molecular dynamics simulation approaches were carried out to assess the docked complex’s conformational stability. A total of 33 drug classes were found from virtual screening based on their docking scores. Among them, seven potential drugs with several anticancer, antibiotic, and immunometabolic categories were screened and showed promising MM/GBSA scores. During interaction analysis, these drugs exhibited different types of hydrogen and hydrophobic interactions with amino acid residue. Besides, 17 experimental drugs selected from virtual screening might be crucial for drug discovery against COVID-19. The RMSD, RMSF, SASA, Rg, and MM/PBSA descriptors from molecular dynamics simulation confirmed the complex’s firm nature. Seven promising drugs for repurposing against SARS-CoV-2 main protease (Mpro), namely sapanisertib, ornidazole, napabucasin, lenalidomide, daniquidone, indoximod, and salicylamide, could be vital for the treatment of COVID-19. However, extensive in vivo and in vitro studies are required to evaluate the mentioned drug’s activity
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