13 research outputs found

    Stress analysis of a stepped shaft with a keyway

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    A stress concentration case which is encountered in practice more than any other is the shoulder fillet. Shafts, axles, spindles, rotors etc., usually involve, in each case, a number of diameters connected by shoulders with fillet radii and very often it is necessary for a keyway to be near a shoulder. The objective in this study is to analyse the stresses in a shouldered shaft with a keyway subjected to an axial tensile load and to study the dependence of the keyway-end stresses on the distance between the shoulder fillet and the keyway end. This is done by performing a finite element analysis of the model. Two three-dimensional models with a grid of 3-D isoparametric solid elements are generated using the GE CALMA software. In Model 1 the keyway cuts into the shoulder fillet whereas in Model 2 the keyway end terminates just before the fillet. The stress determination is done by ANSYS, a powerful finite element analysis package. A comparative study of the two models shows that stress reductions occur at the keyway end when the keyway runs into the shoulder fillet. The results of this analysis also serve as a guide for the prediction of stresses for a stepped shaft with a keyway subjected to a bending moment

    Effectively Predicting the Presence of Coronary Heart Disease Using Machine Learning Classifiers

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    Coronary heart disease is one of the major causes of deaths around the globe. Predicating a heart disease is one of the most challenging tasks in the field of clinical data analysis. Machine learning (ML) is useful in diagnostic assistance in terms of decision making and prediction on the basis of the data produced by healthcare sector globally. We have also perceived ML techniques employed in the medical field of disease prediction. In this regard, numerous research studies have been shown on heart disease prediction using an ML classifier. In this paper, we used eleven ML classifiers to identify key features, which improved the predictability of heart disease. To introduce the prediction model, various feature combinations and well-known classification algorithms were used. We achieved 95% accuracy with gradient boosted trees and multilayer perceptron in the heart disease prediction model. The Random Forest gives a better performance level in heart disease prediction, with an accuracy level of 96%.publishedVersio

    Identification and Comprehensive Genome-Wide Analysis of Glutathione S-Transferase Gene Family in Sweet Cherry (Prunus avium) and Their Expression Profiling Reveals a Likely Role in Anthocyanin Accumulation

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    Glutathione S-transferases (GSTs) in plants are multipurpose enzymes that are involved in growth and development and anthocyanins transportation. However, members of the GST gene family were not identified in sweet cherry (Prunus avium). To identify the GST genes in sweet cherry, a genome-wide analysis was conducted. In this study, we identified 67 GST genes in P. avium genome and nomenclature according to chromosomal distribution. Phylogenetic tree analysis revealed that PavGST genes were classified into seven chief subfamily: TCHQD, Theta, Phi, Zeta, Lambda, DHAR, and Tau. The majority of the PavGST genes had a relatively well-maintained exon–intron and motif arrangement within the same group, according to gene structure and motif analyses. Gene structure (introns-exons) and conserved motif analysis revealed that the majority of the PavGST genes showed a relatively well-maintained motif and exons–introns configuration within the same group. The chromosomal localization, GO enrichment annotation, subcellular localization, syntenic relationship, Ka/Ks analysis, and molecular characteristics were accomplished using various bioinformatics tools. Mode of gene duplication showed that dispersed duplication might play a key role in the expansion of PavGST gene family. Promoter regions of PavGST genes contain numerous cis-regulatory components, which are involved in multiple stress responses, such as abiotic stress and phytohormones responsive factors. Furthermore, the expression profile of sweet cherry PavGSTs showed significant results under LED treatment. Our findings provide the groundwork for future research into induced LED anthocyanin and antioxidants deposition in sweet cherries

    Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

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    Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

    A Non-Integer High-Order Sliding Mode Control of Induction Motor with Machine Learning-Based Speed Observer

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    The induction motor (IM) drives are prone to various uncertainties, disturbances, and non-linear dynamics. A high-performance control system is essential in the outer loop to guarantee the accurate convergence of speed and torque to the required value. Super-twisting sliding mode control (ST-SMC) and fractional-order calculus have been widely used to enhance the sliding mode control (SMC) performance for IM drives. This paper combines the ST-SMC and fractional-order calculus attributes to propose a novel super-twisting fractional-order sliding mode control (ST-FOSMC) for the outer loop speed control of the model predictive torque control (MPTC)-based IM drive system. The MPTC of the IM drive requires some additional sensors for speed control. This paper also presents a novel machine learning-based Gaussian Process Regression (GPR) framework to estimate the speed of IM. The GPR model is trained using the voltage and current dataset obtained from the simulation of a three-phase MPTC based IM drive system. The performance of the GPR-based ST-FOSMC MPTC drive system is evaluated using various test cases, namely (a) electric fault incorporation, (b) parameter perturbation, and (c) load torque variations in Matlab/Simulink environment. The stability of ST-FOSMC is validated using a fractional-order Lyapunov function. The proposed control and estimation strategy provides effective and improved performance with minimal error compared to the conventional proportional integral (PI) and SMC strategies

    Comprehensive Comparative Analysis of the GATA Transcription Factors in Four Rosaceae Species and Phytohormonal Response in Chinese Pear (Pyrus bretschneideri) Fruit

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    The GATA gene family is one of the most important transcription factors (TFs). It extensively exists in plants, contributes to diverse biological processes such as the development process, and responds to environmental stress. Although the GATA gene family has been comprehensively and systematically studied in many species, less is known about GATA genes in Chinese pears (Pyrus bretschneideri). In the current study, the GATA gene family in the four Rosaceae genomes was identified, its structural characteristics identified, and a comparative analysis of its properties was carried out. Ninety-two encoded GATA proteins were authenticated in the four Rosaceae genomes (Pyrus bretschneideri, Prunus avium, Prunus mume, and Prunus persica) and categorized into four subfamilies (Ⅰ–Ⅳ) according to phylogeny. The majority of GATA genes contained one to two introns and conserved motif composition analysis revealed their functional divergence. Whole-genome duplications (WGDs) and dispersed duplication (DSD) played a key role in the expansion of the GATA gene family. The microarray indicated that, among P. bretschneideri, P. avium, P. mume and P. persica, GATA duplicated regions were more conserved between Pyrus bretschneideri and Prunus persica with 32 orthologous genes pairs. The physicochemical parameters, duplication patterns, non-synonymous (ka), and synonymous mutation rate (ks) and GO annotation ontology were performed using different bioinformatics tools. cis-elements respond to various phytohormones, abiotic/biotic stress, and light-responsive were found in the promoter regions of GATA genes which were induced via stimuli. Furthermore, subcellular localization of the PbGATA22 gene product was investigated, showing that it was present in the nucleus of tobacco (Nicotiana tabacum) epidermal cells. Finally, in silico analysis was performed on various organs (bud, leaf, stem, ovary, petal, and sepal) and different developmental stages of fruit. Subsequently, the expression profiles of PbGATA genes were extensively expressed under exogenous hormonal treatments of SA (salicylic acid), MeJA (methyl jasmonate), and ABA (abscisic acid) indicating that play important role in hormone signaling pathways. A comprehensive analysis of GATA transcription factors was performed through systematic biological approaches and comparative genomics to establish a theoretical base for further structural and functional investigations in Rosaceae species

    Genome-wide analysis of plant specific YABBY transcription factor gene family in carrot (Dacus carota) and its comparison with Arabidopsis

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    Abstract YABBY gene family is a plant-specific transcription factor with DNA binding domain involved in various functions i.e. regulation of style, length of flowers, and polarity development of lateral organs in flowering plants. Computational methods were utilized to identify members of the YABBY gene family, with Carrot (Daucus carota) ‘s genome as a foundational reference. The structure of genes, location of the chromosomes, protein motifs and phylogenetic investigation, syntony and transcriptomic analysis, and miRNA targets were analyzed to unmask the hidden structural and functional characteristics YABBY gene family in Carrots. In the following research, it has been concluded that 11 specific YABBY genes irregularly dispersed on all 9 chromosomes and proteins assembled into five subgroups i.e. AtINO, AtCRC, AtYAB5, AtAFO, and AtYAB2, which were created on the well-known classification of Arabidopsis. The wide ranges of YABBY genes in carrots were dispersed due to segmental duplication, which was detected as prevalent when equated to tandem duplication. Transcriptomic analysis showed that one of the DcYABBY genes was highly expressed during anthocyanin pigmentation in carrot taproots. The cis-regulatory elements (CREs) analysis unveiled elements that particularly respond to light, cell cycle regulation, drought induce ability, ABA hormone, seed, and meristem expression. Furthermore, a relative study among Carrot and Arabidopsis genes of the YABBY family indicated 5 sub-families sharing common characteristics. The comprehensive evaluation of YABBY genes in the genome provides a direction for the cloning and understanding of their functional properties in carrots. Our investigations revealed genome-wide distribution and role of YABBY genes in the carrots with best-fit comparison to Arabidopsis thaliana

    Impact of heat stress on agro-morphological, physio-chemical and fiber related paramters in upland cotton (Gossypium hirsutum L.) genotypes

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    The unpredictably changing climatic conditions, especially high temperatures, are putting a continuous threat to sustainable cotton production. The current study was designed to investigate the impact of heat stress on several morpho-physiological, biochemical, and fibre quality-related traits. The results revealed the presence of significant variations in agro-morphological, physio-chemical and staple length-related parameters for upland cotton genotypes and stress treatments. Further analysis of pooled data unveiled that heat stress had a detrimental impact on all studied plant traits. Severe reduction in plant height, nodes per plant, sympodial branches per plant, number of bolls per plant, ginning out-turn, and staple length were recorded under heat stress. A significant reduction in net photosynthetic rate (Pn) up to 28.6 % was observed in cotton genotype BH-200 (24.7 to 19.2 µmole m−2 s−1). The accumulation of hydrogen peroxide (H2O2) was increased from 7.1 % in BH-306 to 28.7 % in BH-200 under heat stress due to the incidence of oxidative stress. A substantial increase in the accumulation of antioxidants i.e., catalase (65 %–74 %), peroxidase (54 %–169 %), and superoxide dismutase (52 %–98 %) was seen under high-temperature stress conditions. The correlation coefficient analysis unveiled a significantly positive correlation of seed cotton yield with nodes per plant (r = 0.432*), net photosynthetic rate (r = 0.829**), peroxidase (r = 0.974**), and superoxide dismutase (r = 0.868**), under heat stress conditions. However, a negative but statistically significant correlation of seed cotton yield with ginning out turn (r = −0.466*), staple length (r = −0.898**), hydrogen peroxide (r = −0.955**) and catalase (r = −0.904**) was also observed. The overall results unveiled that cotton genotype BH-232 has a comparatively higher heat tolerance than other contesting genotypes while BH-306 showed the highest susceptibility to heat stress. Hence, BH-232 could be recommended after its approval for general cultivation in heat-prone areas of Pakistan
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