Handling Clone Mutations in Simulink Models with VCL

Like any other software system, real life Simulink models contain a considerable amount of cloning. These clones are not always identical copies of each other, but actually show a variety of differences from each other despite the overall similarities. Insufficient variability mechanisms provided by the platform make it difficult to create generic structures to represent these clones. Also, complete elimination of clones from the systems may not always be practical, feasible, or cost-effective. In this paper we propose a mechanism for clone management based on Variant Configuration Language (VCL) that provides a powerful variability handling mechanism. In this mechanism, the clones will be managed separate from the models in a non-intrusive way and the original models will not be polluted with extra complexity to manage clone instances. The proposed technique is validated by creating generic solutions for Simulink clones with a variety of differences present between them

Augmenting Machine Learning with Information Retrieval to Recommend Real Cloned Code Methods for Code Completion

Software developers frequently reuse source code from repositories as it saves development time and effort. Code clones accumulated in these repositories hence represent often repeated functionalities and are candidates for reuse in an exploratory or rapid development. In previous work, we introduced DeepClone, a deep neural network model trained by fine tuning GPT-2 model over the BigCloneBench dataset to predict code clone methods. The probabilistic nature of DeepClone output generation can lead to syntax and logic errors that requires manual editing of the output for final reuse. In this paper, we propose a novel approach of applying an information retrieval (IR) technique on top of DeepClone output to recommend real clone methods closely matching the predicted output. We have quantitatively evaluated our strategy, showing that the proposed approach significantly improves the quality of recommendation

Age-mediated changes in the gastrointestinal tract

Physiological functions of the two extreme ends of the age spectrum, children (<18 y old) and older adults (aged 65 y and over), differ from healthy young adults. This consequently affects the pharmacokinetic profiles of administered drugs, which, in turn, impacts upon clinical practice and drug therapy. The gastrointestinal milieu acts as a distinct and vital organ regulating the dissolution, absorption and metabolism of orally ingested drugs. Age-mediated alteration in the physiology and function of the gut can reshape the pharmacokinetics of certain drugs. However, our understanding of this topic is limited. This article references the gut physiology of healthy adults to capture the available evidence in the literature on the extent and nature of the changes in childhood and older age. The gut, as an organ, is examined with regards to the effect of age on luminal fluid, microbiota, transit and motility, and the intestinal mucosa. Whilst drastic developmental changes were observed in certain aspects of the gastrointestinal environment, the examination reveals significant gaps in our knowledge in the physiology and function of the developing or ageing gut. The revelation of the unknown paves the way towards a better characterization of the human gastrointestinal tract for optimized drug therapy in children and older adults

Does sex matter? The influence of gender on gastrointestinal physiology and drug delivery.

We all respond differently to drugs. Personalised medicine aims to improve efficacy and reduce side effects, and efforts are being made to understand the physiological differences that underlie responses to drugs. Genetics, diet and disease state can be key; however, gender also plays an important role in pharmacokinetics, pharmacodynamics and drug toxicity. Differences in metabolism and clearance of drugs as a consequence of distinct hepatic and renal processes in males and females are now much better understood but little is known about gender differences in the gastrointestinal tract. As the recipient of all orally administered medications, differences at this level can have a major impact on drug delivery and bioavailability; yet these continue to be ignored and insufficiently studied in the context of drug disposition. The aim of this review is to highlight the known gender differences in gut physiology. Clinical case studies are presented, where possible, to illustrate the influence of these differences on drug disposition and gaps in current knowledge are highlighted to encourage further research in this area

To Study the Histomorphological Changes in Cerebellar Purkinje Cells after Exposure to Fine Particulate Matter in C57BL/6J Mice

Objective: To study the histomorphological changes in cerebellar Purkinje cells after exposure to fine particulate matter in C57BL/6J mice. Study Design: Laboratory based experimental study. Place and Duration of Study: The study was conducted in the Anatomy department of the Army Medical College, Rawalpindi, from 15 June to 15 September 2020, in coordination with the Military Hospital, Rawalpindi, and the National Institute of Health (NIH), Islamabad. Materials and Methods: Thirty male and female C57BL/6 mice, 8 weeks of age, weighing 37± 2 gm were obtained from NIH, Islamabad. The animals were divided in two groups, 15 mice in each group (8 male and 7 female) Group A were marked as control, received regular diet and water ad libitum. Group B (experimental group) received dynamic inhalation of 3mg/m³ fine particles (soot) through air circulation for 6h/d for 12 weeks, in plastic cabin measuring 2x2x2 feet fitted with two small fans for evenly distribution of Particulate Matter. After exposure period, the animals were sacrificed. After sectioning the tissue and staining, the microscopic analysis was carried out. Purkinje cell margins were evaluated. Number of Purkinje cells and changes in Purkinje cell size were noted. Data was collected, analyzed with the statistical package for social sciences version 23. A p value ≤ 0.05 was considered significant. Result: The Purkinje cell margins were observed to become irregular and corrugated in the experimental groups B when compared with control group A. The number and size of Purkinje cells also showed difference when compared to the control group A. Conclusion: The present study concluded that fine particulate matter induces changes in histomorphological features of mice cerebellar tissue including Purkinje cells

Sphingomyelin as a myelin biomarker in CSF of acquired demyelinating neuropathies

Fast, accurate and reliable methods to quantify the amount of myelin still lack, both in humans and experimental models. The overall objective of the present study was to demonstrate that sphingomyelin (SM) in the cerebrospinal fluid (CSF) of patients affected by demyelinating neuropathies is a myelin biomarker. We found that SM levels mirror both peripheral myelination during development and small myelin rearrangements in experimental models. As in acquired demyelinating peripheral neuropathies myelin breakdown occurs, SM amount in the CSF of these patients might detect the myelin loss. Indeed, quantification of SM in 262 neurological patients showed a significant increase in patients with peripheral demyelination (p\u2009=\u20093.81\u2009*\u200910\u2009-\u20098) compared to subjects affected by non-demyelinating disorders. Interestingly, SM alone was able to distinguish demyelinating from axonal neuropathies and differs from the principal CSF indexes, confirming the novelty of this potential CSF index. In conclusion, SM is a specific and sensitive biomarker to monitor myelin pathology in the CSF of peripheral neuropathies. Most importantly, SM assay is simple, fast, inexpensive, and promising to be used in clinical practice and drug development

Evolution of a physiological pH 6.8 bicarbonate buffer system: application to the dissolution testing of enteric coated products.

The use of compendial pH 6.8 phosphate buffer to assess dissolution of enteric coated products gives rise to poor in vitro-in vivo correlations because of the inadequacy of the buffer to resemble small intestinal fluids. A more representative and physiological medium, pH 6.8 bicarbonate buffer, was developed to evaluate the dissolution behaviour of enteric coatings. The bicarbonate system was evolved from pH7.4 Hanks balanced salt solution to produce a pH 6.8 bicarbonate buffer (modified Hanks buffer, mHanks), which resembles the ionic composition and buffer capacity of intestinal milieu. Prednisolone tablets were coated with a range of enteric polymers: hypromellose phthalate (HP-50 and HP-55), cellulose acetate phthalate (CAP), hypromellose acetate succinate (HPMCAS-LF and HPMCAS-MF), methacrylic acid copolymers (EUDRAGIT® L100-55, EUDRAGIT® L30D-55 and EUDRAGIT® L100) and polyvinyl acetate phthalate (PVAP). Dissolution of coated tablets was carried out using USP-II apparatus in 0.1M HCl for 2h followed by pH 6.8 phosphate buffer or pH 6.8 mHanks bicarbonate buffer. In pH 6.8 phosphate buffer, the various enteric polymer coated products displayed rapid and comparable dissolution profiles. In pH 6.8 mHanks buffer, drug release was delayed and marked differences were observed between the various coated tablets, which is comparable to the delayed disintegration times reported in the literature for enteric coated products in the human small intestine. In summary, the use of pH 6.8 physiological bicarbonate buffer (mHanks) provides more realistic and discriminative in vitro release assessment of enteric coated formulations compared to compendial phosphate buffer

COVID-19 vaccine acceptance and hesitancy in low- and middle-income countries

Widespread acceptance of COVID-19 vaccines is crucial for achieving sufficient immunization coverage to end the global pandemic, yet few studies have investigated COVID-19 vaccination attitudes in lower-income countries, where large-scale vaccination is just beginning. We analyze COVID-19 vaccine acceptance across 15 survey samples covering 10 low- and middle-income countries (LMICs) in Asia, Africa and South America, Russia (an upper-middle-income country) and the United States, including a total of 44,260 individuals. We find considerably higher willingness to take a COVID-19 vaccine in our LMIC samples (mean 80.3%; median 78%; range 30.1 percentage points) compared with the United States (mean 64.6%) and Russia (mean 30.4%). Vaccine acceptance in LMICs is primarily explained by an interest in personal protection against COVID-19, while concern about side effects is the most common reason for hesitancy. Health workers are the most trusted sources of guidance about COVID-19 vaccines. Evidence from this sample of LMICs suggests that prioritizing vaccine distribution to the Global South should yield high returns in advancing global immunization coverage. Vaccination campaigns should focus on translating the high levels of stated acceptance into actual uptake. Messages highlighting vaccine efficacy and safety, delivered by healthcare workers, could be effective for addressing any remaining hesitancy in the analyzed LMICs.Publisher PDFPeer reviewe

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks