Fatigue Strength Analysis and Fatigue Damage Evaluation of Roller Chain

This paper deals with the roller chain commonly used for transmission of mechanical power on many kinds of industrial machinery, including conveyors, cars, motorcycles, bicycles, and so forth. It consists of a series of four components called a pin, a bush, a plate, and a roller, which are driven by a sprocket. To clarify the fatigue damage, in this paper, the finite element method (FEM) is applied to those components under three different types of states, that is, the press-fitting state, the static tensile state, and the sprocket-engaging state. By comparing those states, the stress amplitude and the average stress of each component are calculated and plotted on the fatigue limit diagram. The effect of the plastic zone on the fatigue strength is also discussed. The results show that the fatigue crack initiation may start around the middle inner surface of the bush. As am example, the FEM results show that the fatigue crack of the inner plate may start from a certain point at the hole edge. The results agree with the actual fractured position in roller chains used in industry

Efficacy and feasibility of dose-dense neoadjuvant chemotherapy versus conventional neoadjuvant chemotherapy in patients with HER2-negative breast cancer: A single-center retrospective study

Background: Dose-dense chemotherapy (DDCT) is a standard treatment for patients with high-risk breast cancer. Although there are numerous reports regarding DDCT, it is unclear whether sequential DDCT is effective or feasible as preoperative treatment for Japanese patients. We evaluated the efficacy and safety of neoadjuvant DDCT for patients with human epidermal growth factor receptor 2 (HER2)-negative breast cancer.Methods: This retrospective study evaluated 39 patients with breast cancer, who were preoperatively treated with anthracyclinecontaining regimens and taxanes. According to the chemotherapy regimens patients were divided into the DDCT group (ddgroup) and the conventional chemotherapy (CCT) group (q3w-group). The efficacy of neoadjuvant chemotherapy was evaluated based on the pathological complete response (pCR) rate. Adverse events were evaluated according to the Common Terminology Criteria for Adverse Events version 5.0.Results: There were no apparent differences in tumor stage, histopathological subtype, or surgical procedure. There was not significant difference in the pCR rate (dd-group, 17.6%; q3w-group, 22.7%). Three-year disease-free survival rates were similar in two groups. The rates of dose reduction, delay of treatment, and discontinuation of treatment in the two groups did not differ to a statistically significant extent. There were no significant differences in the adverse events of the two groups

Evidence of mature adipocyte proliferation regulated by proliferin

Despite much research, whether mature adipocytes proliferate remains controversial. Here, we examined 5-bromo-2′-deoxyuridine (BrdU)-labelling of mature adipocytes. Although BrdU incorporation into subcutaneous adipocytes was less than that in visceral adipocytes, pioglitazone (Pio) treatment increased BrdU incorporation in subcutaneous, but not visceral, adipocytes in rats. Fully differentiated 3T3-L1 adipocytes exhibited an increase in cell number and BrdU incorporation with time, with this increase enhanced by Pio treatment. We therefore screened for genes that encode growth factors regulated by Pio, and selected proliferin (PLF). Both gene silencing of PLF by small interfering RNA and treatment with anti-PLF antibody suppressed proliferation in 3T3-L1 adipocytes. In adipocytes isolated from Pio-treated rats, the tissue-specific pattern of PLF expression was similar to that of BrdU incorporation. Administration of an anti-PLF antibody to mice reduced BrdU incorporation into adipocytes. Mature adipocytes thus have the ability to replicate, and this proliferation is positively regulated by PLF

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Romantic relationships developed by international students at some colleges and universities in Hawaiʻi

Thesis (M.A.)--University of Hawaii at Manoa, 2004.Includes bibliographical references (leaves 208-219).xiii, 219 leaves, bound ill. 29 c

Zinc deficiency causes delayed ATP clearance and adenosine generation in rats and cell culture models

Zinc deficiency causes myriad pathophysiological symptoms, but why distinct phenotypes are generated by zinc deficiency remains unclear. Considering that several ectoenzymes involved in purinergic signaling through extracellular adenine-nucleotide hydrolysis possess zinc ions in their active sites, and disorders in purinergic signaling result in diverse diseases that are frequently similar to those caused by zinc deficiency, herein we examine whether zinc deficiency affects extracellular adenine-nucleotide metabolism. Zinc deficiency severely impairs the activities of major ectoenzymes (ENPP1, ENPP3, NT5E/CD73, and TNAP), and also strongly suppresses adenine-nucleotide hydrolysis in cell-membrane preparations or rat plasma, thereby increasing ATP and ADP levels and decreasing adenosine levels. Thus, zinc deficiency delays both extracellular ATP clearance and adenosine generation, and zinc modulates extracellular adenine-nucleotide metabolism. Since the finely tuned balance between extracellular adenine nucleotides and adenosine is critical for purinergic signaling, these findings provide a novel insight into why zinc deficiency results in diverse symptoms

Fast three-dimensional terahertz computed tomography using real-time line projection of intense terahertz pulse

We demonstrated fast three-dimensional transmission terahertz computed tomography by using real-time line projection of intense terahertz beam generated by optical rectification in lithium niobate crystal. After emphasizing the advantage of intense terahertz pulse generation for two-dimensional spatio-temporal terahertz imaging, peak-to-peak amplitudes of pulsed terahertz electric field have been used to obtain a series of projection images at different rotation angles. Then a standard reconstruction algorithm has been employed to perform final three-dimensional reconstruction. Test samples including a medicine capsule have been investigated with a total acquisition time to only 6 minutes

Real-time line projection for fast terahertz spectral computed tomography

We demonstrated fast terahertz spectral computed tomography by using real-time line projection of a terahertz beam. Two types of cross-sectional images of continuously rotating samples have been measured in only a few seconds. From temporal data, a peak-to-peak sinogram and cross sections have been reconstructed using a filtered backprojection algorithm. Using fast Fourier transform from temporal data, spectral cross sections of the sample have been obtained