Fatigue test loading methodfor wagon body basedon measured load

Purpose–In this paper,the C80 special coal gondola car was taken as the subject,and the load test data of the car body at the center plate,side bearing and coupler measured on the dedicated line were broken down to generate the random load component spectrums of the car body under five working conditions,namely expansion,bouncing,rolling,torsion and pitching according to the typical motion attitude of the car body.Design/methodology/approach–On the basis of processing the measured load data,the random load component spectrums were equivalently converted into sinusoidal load component spectrums for bench test based on the principle of pseudo-damage equivalence of load.Relying on the fatigue and vibration test bench of the whole railway wagon,by taking each sinusoidal load component spectrum as the simulation target,the time waveform replication(TWR)iteration technology was adopted to create the drive signal of each loading actuator required for the fatigue test of car body on the bench,and the drive signal was corrected based on the equivalence principle of measured stress fatigue damage to obtain the fatigue test loads of car body under various typical working conditions.Findings–The fatigue test results on the test bench were substantially close to the measured test results on the line.According to the results,the relative error between the fatigue damage of the car body on the test bench and the measured damage on the line was within the range of
16.03%–27.14%.Originality/value–The bench test results basically reproduced the fatigue damage of the key parts of the car body on the line.

Effect of dietary energy level on body weight, testicular development and semen quality of local barred chicken of the western highlands of Cameroon

This study was designed to examine the effects of dietary energy levels on some growth and reproductive parameters of local barred chickens in Cameroon. For this purpose, One hundred and forty four day-old barred male chicks, weighing 28.33 g in average were randomly divided into 12 groups of 12 chicks each. Three feeding programs (FP) comprising each a starter diet from day old to 12 weeks (S0: 2800 Kcal/Kg;S1: 2900 Kcal/Kg;S2: 3000 Kcal/Kg) and grower diet from 13 to 20 weeks (G0: 2900 Kcal/Kg;G1: 3000 Kcal/ Kg;G2: 3100 Kcal/Kg) were used and designated FP1, FP2 and FP3 respectively. Each of the FP was randomly allotted of 4 groups of 12 birds in a completely randomized design. Throughout experiment (1 day old to 20 weeks), body weight was recovered every 2 weeks. At 20 weeks of age, roosters were sacrificed;semen characteristic was analyzed and testes were characterized. Between 2 to 10 weeks old, body weight of cocks fed with FP3 was significantly higher (P < 0.05) as compared to others FP. Inversely, from 12 to 20 weeks, body weight of cocks receiving FP1 was significantly higher (P < 0.05) than that of cocks receiving feeding programs 2 and 3. At 20 weeks, 100% of cocks fed on FP3 produced semen versus 66.66% and 16.66% respectively for those on FP1 and FP2. Semen volume and mass motility of cocks fed on FP3 or FP1 were significantly (P < 0.05) higher than FP2. It was concluded that FP1 had more suitable dietary energy levels for growth and reproduction of local barred cocks.

Early detection and intervention in diabetic gastroparesis:Role of body surface gastric mapping

Diabetic gastrointestinal neuropathy is a diabetes-related complication,associated with a complex interplay of hyperglycemic damage,autoimmune responses,oxidative stress,gastrointestinal hormones,and vascular insufficiency.Patients with diabetes should be monitored and therapeutic intervention introduced to prevent neuropathy due to diabetes prior to“the point of no return”.Determining gastric bioelectrical activity by body surface gastric mapping may be a promising option to monitor diabetic gastrointestinal neuropathy.

Fatigue research of metro car body based on operational loads

Purpose–The principle of infinite life design currently directs fatigue resistance strategies for metro car bodies.However,this principle might not fully account for the dynamic influence of operational loads and the inevitable presence of defects.This study aims to integrate methods of service life estimation and residual life assessment,which are based on operational loads,into the existing infinite life verification framework to further ensure the operational safety of subway trains.Design/methodology/approach–Operational loads and fatigue loading spectra were determined through the field test.The material test was conducted to investigate characteristics of the fracture toughness and the crack growth rate.The fatigue strength of the metro car body was first verified using the finite element method and Moore–Kommers–Japer diagrams.The service life was then estimated by applying the Miner rule and high-cycle fatigue curves in a modified form of the Basquin equation.Finally,the residual life was assessed utilizing a fracture assessment diagram and a fitted curve of crack growth rate adhered to the Paris formula.Findings–Neither the maximum utilization factor nor the cumulative damage exceeds the threshold value of 1.0,the metro car body could meet the design life requirement of 30 years or 6.6 million km.However,three out of five fatigue key points were significantly influenced by the operational loads,which indicates that a single fatigue strength verification cannot achieve the infinite life design objective of the metro car body.For a projected design life of 30 years,the tolerance depth is 12.2 mm,which can underscore a relatively robust damage tolerance capability.Originality/value–The influence of operational loads on fatigue life was presented by the discrepancy analysis between fatigue strength verification results and service life estimation results.The fracture properties of butt-welded joints were tested and used for the damage tolerance assessment.The damage tolerance life can be effectively related by a newly developed equation in this study.It can be a valuable tool to provide the theoretical guidance and technical support for the structural improvements and maintenance decisions of the metro car body.

The Criteria for Reducing Centrally Restricted Three-Body Problem to Two-Body Problem

Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubation of much heavier planets such as Jupiter and Saturn if the natural satellite lies deep inside the respective host Planet Hill sphere. Each planet has a Hill radius aH and planet mean radius RP and the ratio R1=RP/aH. Under very low R1 (less than 0.006) the approximation of CRTBP (centrally restricted three-body problem) to two-body problem is valid and planet has spacious Hill lobe to capture a satellite and retain it. This ensures a high probability of capture of natural satellite by the given planet and Sun’s perturbation on Planet-Satellite binary can be neglected. This is the case with Earth, Mars, Jupiter, Saturn, Neptune and Uranus. But Mercury and Venus has R1=RP/aH =0.01 and 5.9862 × 10-3 respectively hence they have no satellites. There is a limit to the dimension of the captured body. It must be a much smaller body both dimensionally as well masswise. The qantitative limit is a subject of an independent study.

基于试卷分析探讨思维导图及3DBody解剖软件应用于系统解剖学教学的效果

本文以皖南医学院2015级护理专业本科系统解剖学期末试卷分析为基础,探讨了在系统解剖学多媒体结合板书的教学模式中融入思维导图及3D Body解剖软件的教学实践。试卷分析结果表明,将思维导图及3D Body解剖软件融入到现有的教学模式中,有利于学生学习兴趣的激发、主观能动性的充分发挥、自主学习习惯的培养、从局部到整体知识链的构建和形象思维及逻辑思维能力的培养,有助于提高教学质量。

Dent Resistance for Automobile Body Panels

Dent resistance of automobile body panels is an important property for automobile design and manufacture, but the study on this aspect is not still profound. This study is to summarize the testing methods and physical significations of static and dynamic dent resistance of automobile body panels combined with the author＇s study, and to analyze the dent behaviors in the round. Several influence factors on dent resistance are expatiated including the mechanical properties of materials, stress states after forming, bake hardening ability, modulus, methods of testing, and structure of specimens and so on. The automotive lightweight and application of high strength steel sheets and aluminum alloys sheets are analyzed, and the significance of testing of dent resistance, especially for dynamic dent resistance of auto-panels, and the finite element simulation analysis are emphasized. To explain the physical phenomenon of dent behaviors, the latest and concerned study results are also discussed. According to this study, a dent resistance test and evaluation standard of Society of Automotive Engineers of China for automotive body panel is presented and is being carried out, and an industry conference is hold to discuss the working-out of the standard, a primary schedule of this standard is confirmed now. The study can guide the further testing and study of dent resistant of auto-panels.

Body mass index is not associated with sperm-zona pellucida binding ability in subfertile males

Lifestyle factors, such as weight and nutritional status may affect male fertility, including sperm fertilization ability. The objective of this retrospective study was to evaluate the association between body mass index （BMI） and sperm-zona pellucida binding ability assessed according to the zona binding （ZB） test, which has been described to be a relevant diagnostic tool for the prediction of in vitro fertilization （IVF） ability. Three hundred and six male patients from couples diagnosed with primary idiopathic or mild male factor infertility were included. Correlations between BMI and semen parameters according to ZB test indices were assessed, together with frequencies of positive and negative tests across the BMI categories. In this selected population, BMI was not related to conventional semen parameters or sperm quality assessed according to the ability of spermatozoa to bind to the zona pellucida. The previously described poor outcomes of IVF procedures in cases of male obesity could be due to other sperm defects, such as alterations of sperm capacitation or acrosome reaction. The link between male BMI and biological outcomes during IVF procedures, such as fertilization rates, should be further evaluated.

Asymmetry of Testes in Guenther's Frog,Hylarana guentheri(Anuar:Ranidae)

Testes size in most animals commonly shows directional asymmetry. In birds, the left testis mass is usually larger than the right one, but the reports on the testes asymmetry in anurans are very few. Moller （1994） hypothesized that the right testis serves a compensatory role and increases in size when the left one is defective, and further suggested that testes asymmetry may be a reliable indicator of individual body condition. In this paper, we tested the compensation hypothesis in the Guenther＇s frog, Hylarana guentheri. From 60 sampled males, we found that there was a significant directional asymmetry in testes mass, with the left testis size being significantly correlated with relative testes asymmetry, providing evidence that the right testis had a compensatory function. However, testes mass and asymmetry were not correlated with body condition. Hence, we found no evidence that testes asymmetry in the Guenther＇s frog reflected male condition, and male age was also not related to testes mass or asymmetry.

Optimization of food deprivation and sucrose preference test in SD rat model undergoing chronic unpredictable mild stress

Background:The chronic unpredictable mild stress(CUMS)model has long been considered the best model for exploring the pathophysiological mechanisms underlying depression.However,there are no widely recognised standards for strategies for modeling and for behavioral testing.The present study aimed to optimize the protocols for food deprivation and the sucrose preference test(SPT)for the CUMS model.Methods:We first evaluated the effects of different long periods of food deprivation on the body weight of Sprague Dawley(SD)rats by testing food deprivation for 24 hours(8:00-8:00^+),food deprivation for 12 hours during the daytime(8:00-20:00)and food deprivation for 12 hours at night(20:00-8:00^+).Next,we established a SD rat CUMS model with 15 different stimulations,and used body weight measurement,SPT,forced swim test(FST),open field test(OFT)and Morris water maze(MWM)test to verify the success of the modeling.In the SPT,consumption of sucrose and pure water within 1 and 12 hours was measured.Results:Twelve hours of food deprivation during the daytime(8:00-20:00)had no effect on body weight,while 12 hours of food deprivation at night(20:00-8:00^+)and 24 hours of food deprivation(8:00-8:00^+)significantly reduced the mean body weight of the SD rats.When SPT was used to verify the successful establishment of the CUMS rat model,sucrose consumption measured within 12 hours was less variable than that measured within 1 hour.Conclusions:Twelve hours of food deprivation in the daytime(8:00-20:00)may be considered a mild stimulus for the establishment of a CUMS rat model.Measuring sucrose consumption over 12 hours is recommended for SPT.

High prevalence of vitamin A deficiency in Crohn's disease patients according to serum retinol levels and the relative dose-response test

AIM:To assess the vitamin A status of patients with Crohn's disease(CD) by evaluating serum retinol levels and the relative dose response(RDR) test(liver retinol stores).METHODS:Vitamin A nutritional status was measured by serum retinol obtained by high performance liquid chromatography and the RDR test for evaluation of the hepatic stores.Body composition was performed by densitometry by dual-energy X-ray absorptiometry.Vitamin A dietary intake was assessed from a semiquantitative food frequency questionnaire.RESULTS:This study included 38 CD patients and 33 controls.Low serum retinol concentrations were detected in 29% of CD patients vs 15% in controls(P < 0.005).The RDR test was positive in 37% of CD patients vs 12% in controls,which indicated inadequate hepatic vitamin A stores(P < 0.005).Individuals with hypovitaminosis A had lower BMI and body fat compared with those without this deficiency.There was no association between vitamin A deficiency and its dietary intake,ileal location,presence of disease activity and prior bowel resections.CONCLUSION:Patients with CD have higher prevalence of vitamin A deficiency,as assessed by two independent methods.

Research on leakage current test method

In the leakage current test, through the high speed data collection and digital filtering to the output voltage of the human body impedance network, leakage current test that is in accordance with many kinds of electrical safety standards can be realized, and the frequency distribution information of the leakage current can be got as well, which can be used to much more completely evaluate the possible damage degree of the leakage current to the human body and analyze the reason for the appearance of the leakage current in the electric equipment.

Simple schizophrenia revisited: Its schizophrenic body image deviation

Simple schizophrenia has not yet been recognized as a well-established diagnostic category as one of the subtypes of schizophrenia, however, its inclusion to the official diagnostic system is regarded as urgent for early intervention. Here, we report our new observation that body image distortion uniquely found in typical schizophrenia, as reflected in the perception of mass of flesh of living objects in the whole or part of the Rorschach stimuli (Koide et al., 2002), was shown in the patients conforming to the original description of simple schizophrenia, to revisit its relatedness to schizophrenia from a cognitive and perceptual point of view. The Rorschach test was administered to four inpatients of a local mental hospital, showing social and occupational decline, negative symptoms and absence of positive symptoms. The presence or absence of Rorschach flesh mass body image percepts was examined. All of four patients revealed Rorschach mass of flesh responses. The fact that simple schizophrenia exhibited the same body image distortion in the flesh mass passive global perception with typical schizophrenia suggests the adequacy of reconsidering simple schizophrenia as a form of schizophrenia.

Degradation of differently processed Mg-based implants leads to distinct foreign body reactions(FBRs)through dissimilar signaling pathways

Mg alloys have mechanical properties compatible with human bones.However,their rapid degradation and associated foreign body reactions in vivo significantly limit their application for human implants.In this study,three differently processed Mg alloys,pure Mg(PM),cold extruded Mg alloy AZ31(CE AZ31),and fully annealed AZ31 Mg alloy(FA AZ31)were comparatively investigated for their potential as implants using a rat model.All three implanted Mg alloys do not show any impact on hepato-and renal function,nor any signs of observable changes to vital organs.Proteomics analysis of tissues directly contacting the implants 2.5 months post implantation revealed that FA AZ31 activates very few inflammation and immune associated signaling pathways;while the CE AZ31 and PM produce more significant inflammatory responses as confirmed by cytokine array analyses.Further,FA AZ31 activated pathways for cell organization and development that may improve the recovery of injured tissues.Structurally,EBSD analysis reveals that the FA AZ31 alloy has a higher ratio of first-order pyramidal orientated(10–11){10–1–2}grain texture with a value of 0.25,while PM and CE AZ31 alloys have lower ratios of first-order pyramidal orientated texture with the values of 0.16 and 0.17,respectively.This is associated with recovery and recrystallisation during annealing which promotes grain texture which exhibits enhanced degradation behaviours and induces a more limited immune response in vivo.In conclusion,the FA AZ31 demonstrated better biocompatibility and corrosion resistance and is a promising candidate for metal-based degradable implants which warrants further investigation.

Physical Activity and Body Composition Relate to Cardiorespiratory Fitness Independently in Young Adults with Down Syndrome

BACKGROUND： Persons with Down syndrome （DS） typically possess low cardiorespiratory fitness （CRF）, engage in low levels of physical activity （PA）, and display elevated obesity levels, but the association between these variables is not clear in persons with DS. METHOD： We investigated the relationships among measures of CRF, PA, and body composition in 30 young adults with DS （age： 21.3 ± 5.5 years） using a cross-sectional study design. RESULTS： Male participants presented on average with a BMI of 32.9 ± 10.0 kg/m2, a percent body fat of 22.2 ±13.0%, and a six-minute walk distance （6MWD） of 411.7 ± 66.3 m. Female participants presented on average with a BMI of 31.6 ± 13.5 kg/m2, a percent body fat of 26.7 ± 15.1%, and a six-minute walk distance （6MWD） of 360.4 ± 91.2 m. 6MWD shared a positive relationship with leisure time physical activity levels （r = 0.56, β = 1.488） and a negative relationship with body mass index （BMI; r = -0.49, β = -2.561）. No relationship between body composition and PA was found. CONCLUSIONS： It seems that higher PA levels and lower BMI relate to better CRF in young adults with DS. Physical activity and body composition appear to be unrelated in persons with DS.

The Relationship between Maximum Oxygen Consumption （VO2 Max） and Body Fat Percentage of the Male Secondary School Pupils （15-18 Years）

The purpose of this study was to find out the type of relationship between VO2 max and percentage of body fat in male secondary school students. The research sample consisted of 30 male students studying at Al-Khawarizmi High School in Tlemcen. Their average age was 16.56 ± 0.69. We based our research on books and scientific journals, site visits, and personal meeting. We used the descriptive approach. The test was carried out and the measurements were taken at the institution＇s yard and the doctor＇s office respectively. We used the running test for one mile to measure the maximum oxygen consumption. The skin folds were taken in three areas： the chest, abdomen and mid-thigh, to estimate the proportion of fat in the body. The results showed that the relationship between maximum oxygen consumption and body fat percentage was strongly reversed at a significant level of 0.01, with Pearson correlation coefficient -0.597.

EXPERIMENTAL STUDY OF TURBULENT WINGBODY JUNCTION AND WAKE FLOW

The experiments on wing-body junction and wake flow were carried cul in alow-turbulence level wind tunnel. Intensive measurements of various flow parameters,such as the distributions of the pressure on the surfaces of the airfoil and the plate wall,the mean and the fluctuating velocities, as well as the turbulent kinetic energy, u'v' andu'w'etc., were performed. The results indicate that the secondary flow entrains the highvelocity low-turbulence fluid into the boundary layer and the wake vortex dominates thewake flow. Some regions of negative eddy viscosity are also found in the wake flow.

Critical Analysis of Children’s Drawings as a Diagnostic Tool for Body Schema and Body Image Disorder in Cerebral Palsy

Cerebral palsy is a multiple disability manifested by motor deficits and impairments of cognition, language, and body perception. To assess if body schema and body image distortion in children and youth with cerebral palsy can be represented through draw-a-person-test, outcome measure of conscious and subconscious body awareness, visual perception and cognition in two age-matched groups, one with cerebral palsy and other with developmental disability, were collected. The outcome was compared within the two groups and with reference data (healthy population) and correlated with the outcome of draw-a-person test. Decreased scores in the draw-a-person test in subjects with cerebral palsy compared both to subjects with developmental disorders and to healthy population had strongly correlated with decreased scores in visual perception. This suggests that draw-a-person test may provide a preliminary guidance for the assessment of visual perception. No statistically significant effect of cognitive abilities on performance in the draw-a-person test was found. The influence of both conscious and subconscious body awareness on the scores in the draw-a-person test was not significant, which confirms that this test alone is not fully reliable to detect the body schema and body image disorder in cerebral palsy.

静脉注射头孢菌素类药物患者过敏反应发生率及其影响因素的多中心临床研究

目的:分析头孢菌素类药物过敏反应的发生率及其影响因素。方法:横断面调研2021年4月1日至6月30日浙江省29家医疗机构所有接受静脉注射头孢菌素类药物的患者,统计头孢菌素类药物过敏反应的发生率,采用泊松回归模型分析头孢菌素类药物诱导过敏反应发生的相关影响因素。结果:研究共纳入56155例患者,头孢菌素类药物过敏反应总发生率为1.67‰,过敏反应发生率最高的是头孢唑肟(4.27‰),其次是头孢曲松(3.49‰)和头孢噻肟(2.40‰)。与皮试阴性组比较,非皮试组患者过敏反应发生率无明显增加(分别为1.75‰与1.63‰,RR=1.07,95%CI:0.70~1.63,P>0.05)。泊松回归分析结果显示,体重指数低于18.5 kg/m^(2)(RR=2.43,95%CI:1.23~4.82,P<0.05)、其他β-内酰胺类药物过敏史(RR=33.88,95%CI:1.47~781.12,P<0.05)会增加头孢菌素类药物过敏反应的发生率,且与头孢呋辛比较,头孢曲松(RR=3.08,95%CI:1.70~5.59,P<0.01)、头孢他啶(RR=1.89,95%CI:1.03~3.47,P<0.05)和头孢唑肟(RR=3.74,95%CI:1.64~8.50,P<0.01)过敏反应发生的风险增加。结论:头孢菌素类药物过敏反应与低体重指数和β-内酰胺类药物过敏史有关,头孢菌素类药物的常规皮试筛查并不能减少过敏反应发生。

基于表面增强拉曼光谱的肾结石患者体液代谢谱特点及应用价值

目的分析基于表面增强拉曼光谱(SERS)的肾结石患者体液代谢谱特点,探讨其应用价值,为肾结石患者的筛查工作提供参考。方法纳入福建省立医院泌尿外科确诊的25例肾结石患者(结石组)和25例健康体检者(对照组),采集其血液、尿液样本,利用SERS测量样本光谱,再进行平均谱和差异谱绘制。采用主成分分析结合线性判别分析(PCA-LDA)对归一化数据进行处理。最后采用受试者工作特征(ROC)曲线评估PCA-LDA方法的效能。结果结石组患者的体液(血液、尿液)拉曼光谱与对照组之间存在差异。根据既往报道的拉曼峰暂定分配,推测血浆和尿液中各有11种代谢物与肾结石有关,其中结石组尿液中的磷脂酰肌醇、苯丙氨酸、棕榈酸/脂肪酸等含量高于对照组,而尿嘧啶、糖原等成分的含量低于对照组。结石组患者血浆中的甲基带含量高于对照组,而糖原、磷脂酰肌醇、蛋白质-酪氨酸、苯丙氨酸、棕榈酸/脂肪酸、羟脯氨酸/酪氨酸和脂类的含量低于对照组。结论采用SERS检测可发现肾结石患者的尿液和血液代谢成分与健康体检者存在差异,结合PCA-LDA与ROC分析法可能有助于肾结石患者的筛查。