ANALYSIS OF FATIGUE FRACTURE BASED ON PERIDYNAMIC

Perdynamic（PD） is used for analyzing crack propagation in engineering material fracture,the bonds constitute to the constitutive relation of the peridynamic,and the broken bonds represent to material fracture,but it can’t be used for the fatigue analysis.Based on the Miner’s linear cumulative damage theory,the bond fatigue break criterion was proposed instead of the old break criterion,the PD fatigue fracture model for high cycle fatigue was constructed.Finally,a bending fatigue fracture analysis was carried out on a standard involute gear,the results show that the fatigue fracture process for gear by PD fatigue fracture model is consistent with experiment,the PD fatigue fracture model provides a method which consists of life prediction and fatigue crack propagation

Influence of phytohormones and polyamines on the growth and lipid content of Dunaliella bardawil

如何提高微藻的生长速度,获取高生物量的产出,同时保持较高的脂类含量是目前微藻生物质能源研发中面临的普遍问题.本文对比研究了3种植物激素吲哚乙酸(IAA)、赤霉素(gA)和脱落酸(AbA)以及3种多胺腐胺(PuT)、亚精胺(SPd)和精胺(SPM)对巴氏杜氏藻生长和脂类含量的影响.结果表明,3种植物激素和多胺对藻细胞生长均有促进作用.与对照组相比,SPM实验组的细胞密度提高了35.2%,其次为IAA,提高了26.6%.SPM处理同样提高了藻的生物量,达26.1%,而IAA则仅为9.4%.植物激素和多胺同样影响了藻细胞的脂类含量,其中SPM实验组藻细胞脂类含量最高,达29.7%,比对照组提高了22.7%,其次为IAA,提高了20.1%.因此,适量添加植物激素和多胺可有效促进巴氏杜氏藻的生长,提高脂类含量.For mass production of bio-fuel,the economic feasibility of microalgal culture greatly depends on the productivity of biomass and lipids.The influence of 3 phytohormones( IAA,GA,ABA) and 3 polyamines( Put,Spd,Spm) on the growth and lipid content of Dunaliella bardawil( HL-1) were studied.Our results show that the growth of D.bardawil is improved by phytohormone and polyamines.Cell density and biomass in Spm treatment has increased by 35.2% and 26.1% than that of the control,and by 26.6% and 9.4% in IAA treatment,comparatively.Moreover,the cell lipid content is affected by phytohormone and polyamines.The lipid content in Spm treatment is the highest( 29.7%) with 22.7% increase than the control and the next is IAA treatment with 20.1%increase.Therefore,it is useful to add phytohormone and polyamines for the growth and lipid content of D.bardawil.深圳市科技研发资金招研引智资助项目(ZYD201111080010A); 厦门市海洋经济发展专项资助项目(14CZP046HJ20); 福建省科技重点资助项目(2009N0052

Anxiety，depression and insomnia in pregnant women during the COVID － 19 epidemic in Beijing

目的:评估新冠肺炎流行期间孕妇的焦虑抑郁症状与睡眠问题及其相关因素。方法:2020年2月28日-4月26日,通过网络问卷平台调查北京四家助产机构就诊的885例孕妇的焦虑抑郁症状及睡眠问题。采用广泛焦虑量表(GAD-7)评估焦虑症状,采用患者健康问卷抑郁症状群量表(PHQ-9)评估抑郁症状,采用失眠严重程度指数量表(ISI)评估失眠症状。结果:本样本中焦虑症状、抑郁症状及失眠症状检出率分别为12.2%,24.6%和13.6%。缺少照顾(OR=1.73)、有分娩担忧(OR=3.95)及心理弹性差(OR=4.57)是焦虑症状的危险因素;家庭收入高(OR=1.94)、有分娩担忧(OR=2.39)及心理弹性差(OR=3.04)是抑郁症状的危险因素;除已婚外其他婚姻状况(OR=4.95)、孕周较长(13～27周,OR=2.03;28周及以上,OR=2.13)、有躯体疾病史(OR=1.77)、存在分娩担忧(OR=2.78)及心理弹性差(OR=1.67)是失眠症状危险因素。结论:新冠肺炎流行期间北京市孕妇焦虑症状、抑郁症状及失眠症状常见,尤其是存在分娩担忧及心理弹性差的孕妇。</p

Aripiprazole versus other atypical antipsychotics for schizophrenia

BACKGROUND: In most western industrialised countries, second generation (atypical) antipsychotics are recommended as first line drug treatments for people with schizophrenia. In this review we specifically examine how the efficacy and tolerability of one such agent - aripiprazole - differs from that of other comparable second generation antipsychotics. OBJECTIVES: To evaluate the effects of aripiprazole compared with other atypical antipsychotics for people with schizophrenia and schizophrenia-like psychoses. SEARCH METHODS: We searched the Cochrane Schizophrenia Group Trials Register (November 2011), inspected references of all identified studies for further trials, and contacted relevant pharmaceutical companies, drug approval agencies and authors of trials for additional information. SELECTION CRITERIA: We included all randomised clinical trials (RCTs) comparing aripiprazole (oral) with oral and parenteral forms of amisulpride, clozapine, olanzapine, quetiapine, risperidone, sertindole, ziprasidone or zotepine for people with schizophrenia or schizophrenia-like psychoses. DATA COLLECTION AND ANALYSIS: We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. Where possible, we calculated illustrative comparative risks for primary outcomes. For continuous data, we calculated mean differences (MD), again based on a random-effects model. We assessed risk of bias for each included study. MAIN RESULTS: We included 12 trials involving 6389 patients. Aripiprazole was compared to olanzapine, risperidone and ziprasidone. All trials were sponsored by an interested drug manufacturer. The overall number of participants leaving studies early was 30% to 40%, limiting validity (no differences between groups).When compared with olanzapine no differences were apparent for global state (no clinically important change: n = 703, 1 RCT, RR short-term 1.00 95% CI 0.81 to 1.22; n = 317, 1 RCT, RR medium-term 1.08 95% CI 0.95 to 1.22) but mental state tended to favour olanzapine (n = 1360, 3 RCTs, MD total Positive and Negative Syndrome Scale (PANSS) 4.68 95% CI 2.21 to 7.16). There was no significant difference in extrapyramidal symptoms (n = 529, 2 RCTs, RR 0.99 95% CI 0.62 to 1.59) but fewer in the aripiprazole group had increased cholesterol levels (n = 223, 1 RCT, RR 0.32 95% CI 0.19 to 0.54) or weight gain of 7% or more of total body weight (n = 1095, 3 RCTs, RR 0.39 95% CI 0.28 to 0.54).When compared with risperidone, aripiprazole showed no advantage in terms of global state (n = 384, 2 RCTs, RR no important improvement 1.14 95% CI 0.81 to 1.60) or mental state (n = 372, 2 RCTs, MD total PANSS 1.50 95% CI -2.96 to 5.96).One study compared aripiprazole with ziprasidone (n = 247) and both the groups reported similar change in the global state (n = 247, 1 RCT, MD average change in Clinical Global Impression-Severity (CGI-S) score -0.03 95% CI -0.28 to 0.22) and mental state (n = 247, 1 RCT, MD change PANSS -3.00 95% CI -7.29 to 1.29).When compared with any one of several new generation antipsychotic drugs the aripiprazole group showed improvement in global state in energy (n = 523, 1 RCT, RR 0.69 95% CI 0.56 to 0.84), mood (n = 523, 1 RCT, RR 0.77 95% CI 0.65 to 0.92), negative symptoms (n = 523, 1 RCT, RR 0.82 95% CI 0.68 to 0.99), somnolence (n = 523, 1 RCT, RR 0.80 95% CI 0.69 to 0.93) and weight gain (n = 523, 1 RCT, RR 0.84 95% CI 0.76 to 0.94). Significantly more people given aripiprazole reported symptoms of nausea (n = 2881, 3 RCTs, RR 3.13 95% CI 2.12 to 4.61) but weight gain (7% or more of total body weight) was less common in people allocated aripiprazole (n = 330, 1 RCT, RR 0.35 95% CI 0.19 to 0.64). Aripiprazole may have value in aggression but data are limited. This will be the focus of another review. AUTHORS' CONCLUSIONS: Information on all comparisons are of limited quality, are incomplete and problematic to apply clinically. Aripiprazole is an antipsychotic drug with a variant but not absent adverse effect profile. Long-term data are sparse and there is considerable scope for another update of this review as new data emerges from the many Chinese studies as well as from ongoing larger, independent pragmatic trials