الملخص
Objective:To develope and analyze and optimize the performance of some kinds of environmentally friendly flexible X-ray protective materials in attempt to tackle the various environmental and high energy consumption problems in the development of traditional medical X-ray protective clothing.Methods:The Monte Carlo program was used to establish a simplified model of medical X-ray tube. The aim was to carry out numerical simulation and prediction of the shielding materials′ performance against X-ray, prepare the flexible X-ray shielding materials through experiments and test and verify the their shielding performances The development and optimization path was also obtained by comparing the result between simulation and experiment.Results:Bi was the preferred alternative to toxic Pb elements, while W was able to compensate for weak X-ray absorption zone of Bi. The shielding efficiency of the composite material doped with 25% Bi+ 25% W was able to reach 77.8% and 66.3% at 80 and 120 kV p tube voltages, respectively. Conclusions:With both the selection of elements and the optimization of functional particles, the combination of W and Bi is an economical, environmentally friendly, and efficient shielding way within the energy range of medical diagnostic X-rays. The numerical simulation helps reduce experimental costs, shorten the research period, and improve the design efficiency of X-ray shielding materials.
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Objective@#The aim of this study was to observe the changes in cardiorespiratory fitness after high intensity interval training(HIIT), and to provide a reference basis for scientific and reasonable sports plans.@*Methods@#A total of 26 female college students with sedentary lifestyle were randomly allocated into MCT group (n=13) and HIIT group(n=13). All the participants undertook a graded exercise test to obtain VO 2max. The MCT group was trained with 60% VO 2max intensity for 30 min, while HIIT group received exercises with 90% VO 2max intensity every 3 min, intermittent 2 min, for 6 sessions three times a week for 8 weeks. Before and after 8 weeks of training, the subjects were tested for body shape, cardiorespiratory function and aerobic exercise capacity.@*Results@#BMI[(22.34±2.73)(21.56±2.39)kg/m2], percentage of body fat [(31.43±5.65)%, (28.85±5.52)%] of HIIT group and BMI [(22.98±3.23)(22.35±3.09)kg/m2], percentage of body fat [(33.15±4.48)%, (31.48±4.73)%] of MCT group showed significant changes before and after training(P<0.01). For cardiorespiratory function, there was a significant change in VC [(3.30±0.60)(3.61±0.54)L], vital capacity index(56.22±10.73, 63.51±10.53), and MVV [(81.44±20.45, 91.17±15.64)L/min] in HIIT group. There was also a significant change in VC [(3.08±0.41)(3.19±0.36)L] and vital capacity index (52.74±8.66, 55.62±7.88) in MCT group, and there was a significant difference between the two groups(P<0.01). In terms of aerobic exercise capacity, maximal oxygen uptake in HIIT group [(2 204.15±232.39)(2 539.23±339.39)mL/min] and MCT group [(2 136.15±240.76)(2 462.00±318.29)mL/min] increased significantly after training(P<0.01).@*Conclusion@#Both HIIT and MCT can significantly improve lung function and aerobic performance of sedentary female college students, but HIIT is found more effective than MCT training.
الملخص
Objective To analyze the immunogenomic characteristics of antibody repertoire in re-sponse to influenza vaccine in order to provide a theoretical basis for further development of antibody. Meth-ods Based on a time-series immunoglobulin heavy chain ( IGH) repertoire sequencing dataset, we analyzed the immunogenomic characteristics of antibody repertoire in response to trivalent influenza vaccine ( TIV ) from three aspects which included the features in complementarity-determining region 3 ( CDR3 ) , antibody mutation and VDJ usage. Results The frequency of antibody mutation increased significantly upon vaccina-tion. Analysis of the CDR3 region indicated that polar and aromatic amino acids had a higher preference. The length of CDR3 region in naive B cells followed a normal distribution, while specific CDR3 sequences with 15 to 18 amino acids in length occupied a dominant position after vaccination. In addition, the VDJ us-age altered obviously and IGHV3-7-derived antibody had a significant response to the vaccine. Response in-tensity reached the peak on day 7 and gradually weakened over time. Conclusion Antibody repertoire evolves dynamically to express specific antibody upon vaccination and the characteristics of immune responses at sequence level could be used to evaluate their effectiveness.
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Objective To investigate the effects of acidosis on the current change of transient receptor potential channel M7 (TRPM7) and collagen production in mouse cardiac fibroblast (MCFs), and to explore the pathophysiological function of TRPM7 on the cardiac fibrosis. Methods (1) The model of MCFs was established and isolated. (2) MCFs was subcuhured. (3) Patch clamp technique was used to observe the current characteristics of TRPM7 in low PH solutions. (4) The influence of acidic condition on Ca2+ influx in MCFs was recorded by calcium fluorescent indicators. Results (1) There was a high level expression of TRPM7 in MCFs and the electrophysiological characteristics of TRPM7-like (TRPM7L) was similar to that of TRPM7. (2) Ca2+ influx was increased in acidic condition, and the F340/F380 ratio was increased from 1.0 to 4. 6 at pH 4.0 compared with pH 7.0 (t=2.72, P<0.01). Conclusions (1) TRPM7 is the molecular basis of the native TRPM7L in MCFs and TRPM7L plays an important role in Ca2+ influx. (2) The pathophysiological function of MCFs is influenced by regulation of Ca2+ influx mediated by TRPM7L in the condition of acidosis.
الملخص
Objective To investigate the changes of TRPM 7-like current in mouse cardiac fibroblast(CFs) after myocardial infarction and the effect of myocardial ischemia on the TRPM 7 expression and current. Methods (1) The model of myocardial infarction was made and CFs were isolated;(2) CFs were cultured and infected by TRPM 7 siRNA;(3) The effects of myocardial ischemia on TRPM 7 current were recorded by whole cell patch clamp technique;(4) The influences of myocardial isehemia on Ca2+ influx in CFs were recorded by Ca2+ fluorescence imaging. (5) The effects of ischemia on total collagen content of CFs were studied. Results (1) Ca2+ inward current of CFs was increased after myocardial infarction [(16.2±1.7) vs. (7.4±0.7) pA/pF, P<0.053];(2) TRPM 7 current was reduced by 90% after siRNA infection;(3) The total collagen content of CFs after ischemia was approximately 2.3-fold higher than basic value. Conclusions Ca2+ influx in CFs plays an important role in the pathophysiological process of myocardial fibrosis.
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In terms of students,faculty and teaching methods,this article is involved in the problem of postgraduates'innovative ability and put up some solutions to that.The aim of the article is to help postgraduates to improve their innovative ability.