Error estimate and adaptive refinement in mixed discrete least squares meshless method

The node moving and multistage node enrichment adaptive refinement procedures are extended in mixed discrete least squares meshless (MDLSM) method for efficient analysis of elasticity problems. In the formulation of MDLSM method, mixed formulation is accepted to avoid second-order differentiation of shape functions and to obtain displacements and stresses simultaneously. In the refinement procedures, a robust error estimator based on the value of the least square residuals functional of the governing differential equations and its boundaries at nodal points is used which is inherently available from the MDLSM formulation and can efficiently identify the zones with higher numerical errors. The results are compared with the refinement procedures in the irreducible formulation of discrete least squares meshless (DLSM) method and show the accuracy and efficiency of the proposed procedures. Also, the comparison of the error norms and convergence rate show the fidelity of the proposed adaptive refinement procedures in the MDLSM method

Cloning, bioinformatics study and evaluation expression of gene of enterotoxigenic Escherichia coli CFA/I major subunit (CfaB)

زمینه و هدف: اشرشیاکولی انتروتوکسیژنیک (ETEC) عامل اصلی اسهال کودکان در کشورهای در حال توسعه و مسافران به این مناطق می‌باشد. از طریق ساختارهای سطحی به نام فاکتورهای کلونیزاسیون به سلول‌های میزبان متصل می شود. اشرشیاکولی انتروتوکسیژنیک در بسیاری از مناطق شیوع فاکتور کلونیزاسیون نوع یک (CFA/I) از سایر فاکتورهای کلونیزاسیون بیشتر می باشد و این ترکیب به عنوان ترکیب کلیدی در تولید واکسن محسوب می‌گردد. مولکول کد کننده زیر واحد اصلی آنتی ژن فاکتور کلونیزاسیون (CfaB) به عنوان زیر واحد اصلی این فیمبریه کاندیدای مناسبی برای واکسن می‌باشد. این مطالعه با هدف همسانه سازی ژن CfaB و بررسی تولید پروتئین نوترکیب انجام شد. روش بررسی: در این مطالعه توصیفی آزمایشگاهی اطلاعات مربوط به ژن فاکتور کلونیزاسیون CfaB از بانک ژن استخراج شد و پرایمرهای مناسب آن طراحی شدند. با استفاده از واکنش PCR، ژن مورد نظر تکثیر و سپس درون ناقل همسانه‌سازی (pTZ57R/T) و سپس در ناقل بیانی (pET28a(+)) همسانه سازی شد و بیان ژن CfaB مورد ارزیابی قرار گرفت. یافته‌ها: صحت همسانه سازی با استفاده از واکنش هضم آنزیمی و تعیین توالی تایید شد. بیان این توالی در شرایط مختلف مانند دما، میزبان و محیط کشت های مختلف بررسی گردید اما توالی طبیعی در pET 28a بیان نداشت. نتیجه‌گیری: در طول توالی ژن کد کننده زیر واحد اصلی آنتی ژن فاکتور کلونیزاسیون کدون های نادر پشت سرهم وجود دارد که باعث کاهش بیان این پروتئین می شود

(3-Amino­phen­yl)diphenyl­phosphine oxide–2-propanol (1/1)

The title compound, C18H16NOP·C3H8O, was synthesized by the reduction of (3-nitro­phen­yl)diphenyl­phosphine oxide in the presence of 2-propanol as recrystallization solvent. There are two molecules in the asymmetric unit. Each P atom is tetra­coordinated by three C and one O atom from two phenyl fragments, one aniline group and one double-bonded O atom in a distorted tetra­hedral geometry. C—H⋯π and N—H⋯π inter­actions are present. In the crystal structure, a wide range of non-covalent inter­actions consisting of hydrogen bonding [of the types of O—H⋯O, N—H⋯O and C—H⋯O, with D⋯A distances ranging from 2.680 (3) to 3.478 (3) Å] and π–π [centroid–centroid distance of 3.7720 (15) Å] stacking inter­actions connect the various components into a supra­molecular structure

Detection of Acinetobacter baumannii by PCR-ELISA method

زمینه و هدف: اسینتوباکتر بومانی عامل عفونت های دستگاه تنفسی، دستگاه ادراری، خون و زخم ها به خصوص در بخش مراقبت های ویژه می باشد و توانایی کسب مقاومت دارا می باشد. به منظور تشخیص به موقع و پیگیری فرایند درمان این عفونت ها، لازم است که تکنیک ها به طور مستمر اصلاح شوند. با توجه به اینکه تاکنون مطالعه ای در زمینه شناسایی و جداسازی این باکتری در نمونه های بالینی در ایران با روش PCR-ELISA انجام نشده است، این مطالعه با هدف جداسازی اسینتوباکتر بومانی با روش PCR-ELISA انجام شده است. روش بررسی: در این تحقیق روش PCR-ELISA با استفاده از آغازگرهای اختصاصی و پروب بر روی سویه استاندارد مورد بررسی قرار گرفت. بعد از تکثیر و نشاندار کردن توالی ژن gltA، محصول نشاندار در کف میکرو پلیت کوت گردید و با استفاده از آنتی بادی ضد دیگوکسی ژنین کانژوگه با پراکسیداز شناسایی شد. یافته ها: بررسی توالی bp722 از بخش حفظ شده ژن gltA اسینتوباکتر بائومانی و نتایج حاصل از مطالعه بر روی این باکتری با استفاده از روش PCR-ELISA و به کارگیری آغازگرها و پروب نشان داد که این روش علاوه بر دقت و حساسیت، برای تشخیص سریع باکتری مناسب است. نتیجه گیری: نتایج حاصل، حاکی از حساسیت بیشتر و سرعت بالای روش PCR-ELISA در مقایسه با PCR معمولی است. این تکنیک همچنین علاوه بر سهولت بررسی تعداد بیشتر نمونه، از خطر کمتری نسبت به روش PCR معمولی برخوردار است

Presenting a rapid method for detection of Bacillus cereus, Listeria monocytogenes and Campylobacter jejuni in food samples

Objective(s): Listeria monocytogens, Bacillus cereus and Campylobacter jejuni are three toxin producing bacteria over the world, especially in Iran, and it is essential to find a certain, rapid procedure to identify these microorganisms. In this research, these bacteria were simultaneously detected by multiplex PCR technique in foods. Materials and Methods: The primary approval of bacterial strains was performed by biochemical tests. PCR primers were designed based on the nucleotide sequences of the NHEB/NHEC gene of B. cereus, the hly gene of L. monocytogenes and the C gene of C. jejuni. The specificity of Multiplex PCR method was determined using seven food poisoning bacteria including Salmonella typhi, Shigella dysentery, Yersinia pestis, Staphylococcus aureus, Clostridium perfringens, Clostridium botulinum and Vibrio cholerae. To confirm the reaction, DNA extraction was performed from 30 food samples (milk), and gene amplification was performed by PCR. The length of amplified fragments was 300 bp, 210 bp and 160 bpfor NHEB/NHEC, hly and C genes, respectively. Results: The detection limits of the PCR method were 5, 4 and 3 pg for L. monocytogenes, B. cereus and C. jejuni, respectively. Specifisity test showed that this reaction is spesific to these 3 bacteria. Conclusion: In this study, we  introduced a new multiplex PCR method for simultsnus detection of L. monocytogens, B. cereus and C. jejuni. These results can be used  for detection of other toxin producing bacteria in food

Development of quantitative competitive PCR for determination of copy number and expression level of the synthetic glyphosate oxidoreductase gene in transgenic canola plants

Background: For successful in vitro plant regeneration, plant cell lines with multiple transgene integration and low transgene expression levels need to be ruled out. Although real-time polymerase chain reaction (real-time PCR) is a rapid way to accomplish this, it is also expensive and typically limits the size of the target sequence. Quantitative competitive PCR (QC-PCR) is proven to be a safe and accurate method for determination of both copy number and quantification of transcript levels of synthetic transgenes in transformed plants.Results: The glyphosate oxidoreductase gene was chemically synthesized and used to transform Brassica napus L. via Agrobactrium -mediated transformation. A construct containing the mutated form of a synthetic glyphosate oxidoreductase (gox) gene (internal standard) was prepared. Gene copy number was estimated in nine independent transgenic lines using QC-PCR as well as the standard method of Southern blot analysis. By quantitative competitive reverse transcriptase PCR (QC-RT-PCR), transcript levels were also determined in these lines. High (> 3), medium to high (2.2-3), medium to low (1-2.2), and low (< 1) levels of transcript were detected. Conclusions: No direct relationship was found between copy number and transgene expression levels. QC-PCR method could be implemented to screen putative transgenic plants and quickly select single T-DNA inserts. QC-PCR methods and the prepared competitor construct may be useful for future quantification of commercial transgenic food and feed

Detection of Nocardia, Streptomyces and Rhodococcus from bronchoalveolar lavage specimens of patients with HIV by Multiplex PCR Assay

Background: Nocardia, Streptomyces and Rhodococcus are life threatening opportunistic pathogens under immunodeficiency conditions, particularly among patients infected with HIV. Rapid and accurate detection of these infections can improve immune health quality, patient management and appropriate treatment. The aim of this study was to design a novel multiplex-PCR assay for rapid diagnosis of these three organisms directly from bronchoalveolar lavage (BAL) specimens of patients infected with HIV.Methods: The genus specific primers were designed for directdetection of Nocardia, Streptomyces and Rhodococcus in a single tube multiplex PCR. This PCR specifically amplified the target genes from pure cultures. It subsequently was applied on BAL specimens of 29 HIV positive patients that had previously been culture negative for actinomycete bacteria, of which Nocardia, Streptomyces and Rhodococcus are members.Results: Of 29 respiratory clinical specimens, there were positive for Nocardia spp. and one was positive for Streptomyces spp using the multiplex PCR assay. The sequencing of the PCR products identified the species as Nocardia cyriacigeorgica (n=2), Nocardia farcinica and Streptomyces albus.Conclusion: This novel multiplex PCR assay yielded reliable results for accurate identification of Nocardia, Streptomyces and Rhodococcus from BAL while the results of bacterial culture were negative.

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

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe