492 research outputs found
Predictors of Musculoskeletal Disorders Among Teachers: An Exploratory Investigation in Malaysia
Purpose: The present study aimed to examine the prevalence and gender differences in MSDs among teachers, as well as the interaction of associated predictor .In addition, another aim of the study was to investigate the contribution of these predictors, which have not been examined thoroughly particularly in Malaysia. Methodology: A cross-sectional study was employed in this study. A questionnaire was used to measure physical factors, psychosocial factors, workload, work-life balance, general well-being, and MSDs levels among primary school teachers (N=460) from 10 primary schools in Kota Kinabalu. Findings: The prevalence of MSD in the past 6 months was 61.7% (95% CI: 57.4% – 65.9%). The present study findings also indicated that there were significant gender differences in MSDs between female and male teachers (t = 1.04, p< .05). Hierarchical multiple regression was conducted to examine a range of predictors related to MSDs. Physical factors (ß = .17, p<0.05). Multiple regression was used for a variety of predictors that are associated with MSD. Physical factors (ß = .17, p<0.05), psychosocial factors (ß = -.14, p<0.05), and general well-being (ß = .43, p<0.01) are significantly associated with MSD in Malaysian primary school teachers. Overall, model statistic result was F (3, 276) = 36.730, p=0.001, R² = .45 and adjusted R² = .435. The model explained 44.7% (r= 0.67) of the variance in MSD discomfort. Conclusion: The studies concerning MSDs among teachers revealed the need for a significant effort, not only to examine the risk factors but also to develop interventions to minimize MSDs for those in the teaching profession
Mechanism of Evolution Shared by Gene and Language
We propose a general mechanism for evolution to explain the diversity of gene
and language. To quantify their common features and reveal the hidden
structures, several statistical properties and patterns are examined based on a
new method called the rank-rank analysis. We find that the classical
correspondence, "domain plays the role of word in gene language", is not
rigorous, and propose to replace domain by protein. In addition, we devise a
new evolution unit, syllgram, to include the characteristics of spoken and
written language. Based on the correspondence between (protein, domain) and
(word, syllgram), we discover that both gene and language shared a common
scaling structure and scale-free network. Like the Rosetta stone, this work may
help decipher the secret behind non-coding DNA and unknown languages.Comment: 15 pages, 13 figures, 3 tabl
Variable-heavy (VH) families influencing IgA1&2 engagement to the antigen, FcαRI and superantigen proteins G, A, and L
Interest in IgA as an alternative antibody format has increased over the years with much remaining to be investigated in relation to interactions with immune cells. Considering the recent whole antibody investigations showing significant distal effects between the variable (V) and constant (C)- regions that can be mitigated by the hinge regions of both human IgA subtypes A1 and A2, we performed an in-depth mechanistic investigation using a panel of 28 IgA1s and A2s of both Trastuzumab and Pertuzumab models. FcαRI binding were found to be mitigated by the differing glycosylation patterns in IgA1 and 2 with contributions from the CDRs. On their interactions with antigen-Her2 and superantigens PpL, SpG and SpA, PpL was found to sterically hinder Her2 antigen binding with unexpected findings of IgAs binding SpG at the CH2-3 region alongside SpA interacting with IgAs at the CH1. Although the VH3 framework (FWR) is commonly used in CDR grafting, we found the VH1 framework (FWR) to be a possible alternative when grafting IgA1 and 2 owing to its stronger binding to antigen Her2 and weaker interactions to superantigen Protein L and A. These findings lay the foundation to understanding the interactions between IgAs and microbial superantigens, and also guide the engineering of IgAs for future antibody applications and targeting of superantigen-producing microbes
The Haldane Energy Gap of A Doped Linear-Chain Heisenberg Antiferromagnet
Using the valence-bond-solid (VBS) approach and the Schwinger boson mean
field approximation, we study the dependence of the Haldane gap of a spin-1
linear chain Heisenberg antiferromagnet on impurity doping with different
spins. The impurity spins affect the singlet pairing order parameter
and the constraint factor . As a result, the Haldane gap is reduced by
a factor , with as the impurity concentration, and
eventually collapses at with as the VBS correlation
length. This theoretical prediction can be verified by neutron scattering
experiments.Comment: REVTEX, 12 pages, no figure
Application of RELUX simulation to investigate energy saving potential from daylighting in a new educational building in UK
Daylighting is a renewable energy solution for illumination and visual comfort in buildings. Daylighting performance and its induced energy saving largely depends on various factors, including room geometry, window-to-wall ratio, window transmittance, surface reflectance of construction and surrounding obstructers, artificial lighting array, its daylight-related control strategies and so forth. During the last few decades, lighting simulation tools developed quickly to provide researchers and architects a faster and reliable ways to simulate complex lighting environment. The aim of this paper is to deal with a quantitative analysis of annual energy saving potential from daylighting in a real building using various methods. A case study of a newly constructed educational atrium building, Engineering and Science Learning Centre (ESLC) in the University of Nottingham, UK, is presented. Computational analysis using validated lighting simulation tool RELUX will be conducted to simulate the daylighting performance in the selected rooms. Particularly, an economical measurement of window transmittance and interior surface reflectance will be conducted, and the measured results will be input into the simulation software to increase the accuracy of simulation results. The annual energy saving potential in artificial lighting from daylighting is determined by European Standard EN15193 and also estimated using static climate-based Daylight Factor (DF) method and dynamic climate-based Daylight Coefficient (DC) methods
Spinor Bose-Einstein condensates
An overview on the physics of spinor and dipolar Bose-Einstein condensates
(BECs) is given. Mean-field ground states, Bogoliubov spectra, and many-body
ground and excited states of spinor BECs are discussed. Properties of
spin-polarized dipolar BECs and those of spinor-dipolar BECs are reviewed. Some
of the unique features of the vortices in spinor BECs such as fractional
vortices and non-Abelian vortices are delineated. The symmetry of the order
parameter is classified using group theory, and various topological excitations
are investigated based on homotopy theory. Some of the more recent developments
in a spinor BEC are discussed.Comment: To appear in Physics Reports. The PDF file with high resolution
figures is available from the following website:
http://cat.phys.s.u-tokyo.ac.jp/publication/review_of_spinorBEC.pd
Diagnosing Sarcopenia with AI-Aided Ultrasound (DINOSAUR)—A Pilot Study
Background: Sarcopenia has been recognized as a determining factor in surgical outcomes and is associated with an increased risk of postoperative complications and readmission. Diagnosis is currently based on clinical guidelines, which includes assessment of skeletal muscle mass but not quality. Ultrasound has been proposed as a useful point-of-care diagnostic tool to assess muscle quality, but no validated cut-offs for sarcopenia have been reported. Using novel automated artificial intelligence (AI) software to interpret ultrasound images may assist in mitigating the operator-dependent nature of the modality. Our study aims to evaluate the fidelity of AI-aided ultrasound as a reliable and reproducible modality to assess muscle quality and diagnose sarcopenia in surgical patients. Methods: Thirty-six adult participants from an outpatient clinic were recruited for this prospective cohort study. Sarcopenia was diagnosed according to Asian Working Group for Sarcopenia (AWGS) 2019 guidelines. Ultrasonography of the rectus femoris muscle was performed, and images were analyzed by an AI software (MuscleSound® (Version 5.69.0)) to derive muscle parameters including intramuscular adipose tissue (IMAT) as a proxy of muscle quality. A receiver operative characteristic (ROC) curve was used to assess the predictive capability of IMAT and its derivatives, with area under the curve (AUC) as a measure of overall diagnostic accuracy. To evaluate consistency between ultrasound users of different experience, intra- and inter-rater reliability of muscle ultrasound parameters was analyzed in a separate cohort using intraclass correlation coefficients (ICC) and Bland–Altman plots. Results:The median age was 69.5 years (range: 26–87), and the prevalence of sarcopenia in the cohort was 30.6%. The ROC curve plotted with IMAT index (IMAT% divided by muscle area) yielded an AUC of 0.727 (95% CI: 0.551–0.904). An optimal cut-off point of 4.827%/cm2 for IMAT index was determined with a Youden’s Index of 0.498. We also demonstrated that IMAT index has excellent intra-rater reliability (ICC = 0.938, CI: 0.905–0.961) and good inter-rater reliability (ICC = 0.776, CI: 0.627–0.866). In Bland–Altman plots, the limits of agreement were from −1.489 to 1.566 and −2.107 to 4.562, respectively. Discussion: IMAT index obtained via ultrasound has the potential to act as a point-of-care evaluation for sarcopenia screening and diagnosis, with good intra- and inter-rater reliability. The proposed IMAT index cut-off maximizes sensitivity for case finding, supporting its use as an easily implementable point-of-care test in the community for sarcopenia screening. Further research incorporating other ultrasound parameters of muscle quality may provide the basis for a more robust diagnostic tool to help predict surgical risk and outcomes.</p
Identification of QTL genes for BMD variation using both linkage and gene-based association approaches
Low bone mineral density (BMD) is a risk factor for osteoporotic fracture with a high heritability. Previous large scale linkage study in Northern Chinese has identified four significant quantitative trait loci (QTL) for BMD variation on chromosome 2q24, 5q21, 7p21 and 13q21. We performed a replication study of these four QTL in 1,459 Southern Chinese from 306 pedigrees. Successful replication was observed on chromosome 5q21 for femoral neck BMD with a LOD score of 1.38 (nominal p value = 0.006). We have previously identified this locus in a genome scan meta-analysis of BMD variation in a white population. Subsequent QTL-wide gene-based association analysis in 800 subjects with extreme BMD identified CAST and ERAP1 as novel BMD candidate genes (empirical p value of 0.032 and 0.014, respectively). The associations were independently replicated in a Northern European population (empirical p value of 0.01 and 0.004 for CAST and ERAP1, respectively). These findings provide further evidence that 5q21 is a BMD QTL, and CAST and ERAP1 may be associated with femoral neck BMD variation
Role of the Functional Toll-Like Receptor-9 Promoter Polymorphism (-1237T/C) in Increased Risk of End-Stage Renal Disease:A Case-Control Study
Inflammation induced by infectious and noninfectious triggers in the kidney may lead to end stage renal disease (ESRD). Toll-like receptor 9 (TLR-9) a receptor for CpG DNA is involved in activation of immune cells in renal disease and may contribute to chronic inflammatory disease progression through an interleukin-6 (IL-6) dependent pathway. Previous studies indicate that -1237T/C confers regulatory effects on TLR-9 transcription. To date the effect of TLR-9 polymorphisms on ESRD remains unknown. We performed a case-control study and genotyped 630 ESRD patients and 415 controls for -1237T/C, -1486T/C and 1635G/A by real-time PCR assays and assessed plasma concentration of IL-6 by ELISA. Haplotype association analysis was performed using the Haploview package. A luciferase reporter assay and real-time PCR were used to test the function of the -1237T/C promoter polymorphism. A significant association between -1237T/C in TLR-9 and ESRD was identified. The TCA, TTA and CCA haplotype of TLR-9 were associated with ESRD. ESRD patients carrying -1237TC had a higher mean plasma IL-6 level when compared with -1237TT. The TLR-9 transcriptional activity of the variant -1237CC allele is higher than the -1237TT allele. The results indicate that in a Han Chinese population the presence of the C allele of -1237T/C in the TLR-9 gene increases susceptibility towards development of ESRD. In vitro studies demonstrate that -1237T/C may be involved in the development of ESRD through transcriptional modulation of TLR-9
The Histone H3K79 Methyltransferase Dot1L Is Essential for Mammalian Development and Heterochromatin Structure
Dot1 is an evolutionarily conserved histone methyltransferase specific for lysine 79 of histone H3 (H3K79). In Saccharomyces cerevisiae, Dot1-mediated H3K79 methylation is associated with telomere silencing, meiotic checkpoint control, and DNA damage response. The biological function of H3K79 methylation in mammals, however, remains poorly understood. Using gene targeting, we generated mice deficient for Dot1L, the murine Dot1 homologue. Dot1L-deficient embryos show multiple developmental abnormalities, including growth impairment, angiogenesis defects in the yolk sac, and cardiac dilation, and die between 9.5 and 10.5 days post coitum. To gain insights into the cellular function of Dot1L, we derived embryonic stem (ES) cells from Dot1L mutant blastocysts. Dot1L-deficient ES cells show global loss of H3K79 methylation as well as reduced levels of heterochromatic marks (H3K9 di-methylation and H4K20 tri-methylation) at centromeres and telomeres. These changes are accompanied by aneuploidy, telomere elongation, and proliferation defects. Taken together, these results indicate that Dot1L and H3K79 methylation play important roles in heterochromatin formation and in embryonic development
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