A Continuum Solution to the Problems of Composite Laminate Analysis

In this paper, a method of solution and some numerical results of free vibration and buckling of composite laminates are presented. All the edges of the laminates are assumed as simply supported. Ritz's method of solution is used with deflection surface expressed in terms of double series in Chebyshev polynomials satisfying the simply supported laminate boundary conditions. The numerical results obtained using the present analysis for isotropic as well as orthotropic plate cases, are compared with the available results. A detailed investigation on ht unnatural frequencies and mode shapes of fourlayered, simply supported composite laminates made up of graphite FRP is then undertaken. Numerical results for the first few frequencies and the critical buckling values of symmetric and antisymmetric laminates so obtained, are presented her

Vitamin D and people with intellectual disability

Copyright © 2008 Royal Australian College of General Practitioners Copyright to Australian Family Physician. Reproduced with permission. Permission to reproduce must be sought from the publisher, The Royal Australian College of General Practitioners.BACKGROUND: Vitamin D is essential for the normal functioning of a diverse range of metabolic processes, especially bone health. It is widely appreciated that the elderly are at increased risk of vitamin D insufficiency, but it is less well known that people with intellectual disability are also at increased risk. OBJECTIVE: This article summarises the issues regarding vitamin D in people with intellectual disability, making recommendations about screening, management and follow up. DISCUSSION: The prevalence of intellectual disability in the Australian population has been estimated at just over 1%, implying that most general practitioners will care for several people with intellectual disability. Relatively simple steps are likely to have a significant impact on the health of this vulnerable group of people.Simon Vanlint, Michael Nugent and Seeta Durvasul

Estimate of CRP and TNF-alpha level before and after periodontal therapy in cardiovascular disease patients

Introduction: Epidemiological studies show that individuals with periodontitis have a radically amplified threat to develop cardiovascular disease. CRP& TNF-α, are acute phase proteins monitored as a marker of inflammatory status, which have been identified as a major risk factor for atherosclerotic complications. Elevated CRP & TNF-α level in periodontitis patients have been reported by several groups. The present study was performed to determine whether presence of periodontitis and periodontal therapy could influence the serum levels of CRP & TNF-α in cardiovascular disease patients. Methods: Forty cardiovascular disease subjects participated in the study. They were classified into two groups. Group A (Control) where no periodontal treatment was given, Group B (Test) where periodontal treatment (scaling & root planing) was performed. Periodontal clinical parameters like OHI-S, probing pocket depth, were evaluated together with serum CRP, TNF-α, at baseline and reassessed after 8 weeks for all the subjects in both the groups. Results: The CRP & TNF-α levels in both the groups decreased but the decrease in the Group A was minimal and was not statistically significant (P>0.05); whereas in Group B where periodontal therapy was performed, there was statistically significant decrease. Conclusion: It can be concluded from the study that there can be a possible causal relationship between pathogenesis of periodontal disease and CVD as inferred from the statistical significant outcome in the form of decreased inflammatory biomarkers after the periodontal treatment.Key words: CVD, CRP, TNF-alpha, lipopolysaccharide, periodontiti

Protesto cambiário: conceito, histórico e natureza jurídica

O autor procura mostrar o que é e a que se destina o protesto cambiário. Define conceito, sua natureza jurídica, e faz um relato histórico desde a sua origem, até os dias de hoje

In Silico Binding of 2-Aminocyclobutanones to SARS-CoV-2 Nsp13 Helicase and Demonstration of Antiviral Activity

The landscape of viral strains and lineages of SARS-CoV-2 keeps changing and is currently dominated by Delta and Omicron variants. Members of the latest Omicron variants, including BA.1, are showing a high level of immune evasion, and Omicron has become a prominent variant circulating globally. In our search for versatile medicinal chemistry scaffolds, we prepared a library of substituted α-aminocyclobutanones from an α-aminocyclobutanone synthon (11). We performed an in silico screen of this actual chemical library as well as other virtual 2-aminocyclobutanone analogs against seven SARS-CoV-2 nonstructural proteins to identify potential drug leads against SARS-CoV-2, and more broadly against coronavirus antiviral targets. Several of these analogs were initially identified as in silico hits against SARS-CoV-2 nonstructural protein 13 (Nsp13) helicase through molecular docking and dynamics simulations. Antiviral activity of the original hits as well as α-aminocyclobutanone analogs that were predicted to bind more tightly to SARS-CoV-2 Nsp13 helicase are reported. We now report cyclobutanone derivatives that exhibit anti-SARS-CoV-2 activity. Furthermore, the Nsp13 helicase enzyme has been the target of relatively few target-based drug discovery efforts, in part due to a very late release of a high-resolution structure accompanied by a limited understanding of its protein biochemistry. In general, antiviral agents initially efficacious against wild-type SARS-CoV-2 strains have lower activities against variants due to heavy viral loads and greater turnover rates, but the inhibitors we are reporting have higher activities against the later variants than the wild-type (10–20X). We speculate this could be due to Nsp13 helicase being a critical bottleneck in faster replication rates of the new variants, so targeting this enzyme affects these variants to an even greater extent. This work calls attention to cyclobutanones as a useful medicinal chemistry scaffold, and the need for additional focus on the discovery of Nsp13 helicase inhibitors to combat the aggressive and immune-evading variants of concern (VOCs)

African genomes illuminate the early history and transition to selfing in Arabidopsis thaliana

Over the past 20 y, many studies have examined the history of the plant ecological and molecular model, Arabidopsis thaliana, in Europe and North America. Although these studies informed us about the recent history of the species, the early history has remained elusive. In a large-scale genomic analysis of African A. thaliana, we sequenced the genomes of 78 modern and herbarium samples from Africa and analyzed these together with over 1,000 previously sequenced Eurasian samples. In striking contrast to expectations, we find that all African individuals sampled are native to this continent, including those from sub-Saharan Africa. Moreover, we show that Africa harbors the greatest variation and represents the deepest history in the A. thaliana lineage. Our results also reveal evidence that selfing, a major defining characteristic of the species, evolved in a single geographic region, best represented today within Africa. Demographic inference supports a model in which the ancestral A. thaliana population began to split by 120-90 kya, during the last interglacial and Abbassia pluvial, and Eurasian populations subsequently separated from one another at around 40 kya. This bears striking similarities to the patterns observed for diverse species, including humans, implying a key role for climatic events during interglacial and pluvial periods in shaping the histories and current distributions of a wide range of species

Phonology modulates the illusory vowels in perceptual illusions: Evidence from Mandarin and English

Native speakers perceive illusory vowels when presented with sound sequences that do not respect the phonotactic constraints of their language (Dupoux, Kakehi, Hirose, Pallier, & Mehler, 1999; Kabak & Idsardi, 2007). There is, however, less work on the quality of the illusory vowel. Recently, it has been claimed that the quality of the illusory vowel is also modulated by the phonology of the language, and that the phenomenon of illusory vowels can be understood as a result of the listener reverse inferring the best parse of the underlying representation given their native language phonology and the acoustics of the input stream (Durvasula & Kahng, 2015). The view predicts that listeners are likely to hear different illusory vowels in different phonological contexts. In support of this prediction, we show through two perceptual experiments that Mandarin Chinese speakers (but not American English speakers) perceive different illusory vowels in different phonotactic contexts. Specifically, when presented with phonotactically illegal alveopalatal coda consonants, Mandarin speakers perceived an illusory /i/, but in illegal alveolar stop coda contexts, they perceived a /?/

Gene expression drives the evolution of dominance.

Dominance is a fundamental concept in molecular genetics and has implications for understanding patterns of genetic variation, evolution, and complex traits. However, despite its importance, the degree of dominance in natural populations is poorly quantified. Here, we leverage multiple mating systems in natural populations of Arabidopsis to co-estimate the distribution of fitness effects and dominance coefficients of new amino acid changing mutations. We find that more deleterious mutations are more likely to be recessive than less deleterious mutations. Further, this pattern holds across gene categories, but varies with the connectivity and expression patterns of genes. Our work argues that dominance arises as a consequence of the functional importance of genes and their optimal expression levels

African genomes illuminate the early history and transition to selfing in Arabidopsis thaliana

Over the past 20 y, many studies have examined the history of the plant ecological and molecular model, Arabidopsis thaliana, in Europe and North America. Although these studies informed us about the recent history of the species, the early history has remained elusive. In a large-scale genomic analysis of African A. thaliana, we sequenced the genomes of 78 modern and herbarium samples from Africa and analyzed these together with over 1,000 previously sequenced Eurasian samples. In striking contrast to expectations, we find that all African individuals sampled are native to this continent, including those from sub-Saharan Africa. Moreover, we show that Africa harbors the greatest variation and represents the deepest history in the A. thaliana lineage. Our results also reveal evidence that selfing, a major defining characteristic of the species, evolved in a single geographic region, best represented today within Africa. Demographic inference supports a model in which the ancestral A. thaliana population began to split by 120-90 kya, during the last interglacial and Abbassia pluvial, and Eurasian populations subsequently separated from one another at around 40 kya. This bears striking similarities to the patterns observed for diverse species, including humans, implying a key role for climatic events during interglacial and pluvial periods in shaping the histories and current distributions of a wide range of species.Peer Reviewe