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轿车变速器的表面致密化粉末冶金齿轮的使用性能

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粉末冶金技术 2012年第4期30卷 313-315页

作者： Cünter Rau Lorenz S Sigl Gerold mrk frank Wattenberg 韩凤麟 PmG Füssen GmbH GETRAG Innovation Center Werkzeugmaschinenlabor

选择性表面致密化是改进粉末冶金钢的一种方法,高负载齿轮经过这种加工工艺处理,就能达到使用要求。本文介绍了粉末冶金螺旋齿轮的制造工艺与性能,用三轴总成成对试验台架、承载能力试验台架及噪声试验台架测定了齿轮的使用性能,并把试... 详细信息

选择性表面致密化是改进粉末冶金钢的一种方法,高负载齿轮经过这种加工工艺处理,就能达到使用要求。本文介绍了粉末冶金螺旋齿轮的制造工艺与性能,用三轴总成成对试验台架、承载能力试验台架及噪声试验台架测定了齿轮的使用性能,并把试验结果和具有同样几何形状与表面质量的锻钢齿轮的数据进行了比较。结果表明,粉末冶金齿轮的承载能力与噪声级可和锻钢齿轮相媲美。

关键词：粉末冶金齿轮选择性表面致密化

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Heart rate response and recovery during exercise predict future delirium risk——A prospective cohort study in middle-to older-aged adults

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作者： frank m.·怀特(frank m. White)原

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Journal of Sport and Health Science 2023年第3期12卷 312-323页

作者： Lei Gao Aden Gaba Peng Li Richa Saxena frank A.J.LScheer Oluwaseun Akeju martin K.Rutter Kun Hu Department of Anesthesia Critical Care and Pain MedicineMassachusetts General HospitalHarvard Medical SchoolBostonMA 02114USA medical Biodynamics Program Brigham and Women's HospitalBostonMA 02115USA Division of Sleep medicine Harvard Medical SchoolBostonMA 02115USA Broad Institute of massachusetts Institute of Technology and Harvard CambridgeMA 02142USA Center for Genomic medicine Massachusetts General HospitalBostonMA 02114USA Division of Diabetes Endocrinology and GastroenterologySchool of Medical SciencesFaculty of BiologyMedicine and HealthManchester Academic Health Science CentreUniversity of ManchesterManchester M139PLUK Diabetes Endocrinology and Metabolism CentreManchester University National Health Service Foundation TrustManchester M139WLUK

Background:Delirium is a neurocognitive disorder characterized by an abrupt decline in attention,awareness,and cognition after surgical/illness-induced stressors on the *** is now an increasing focus on how cardiovascular health interacts with neurocognitive disorders given their overlapping risk factors and links to subsequent dementia and *** common indicator for cardiovascular health is the heart rate response/recovery(HRR)to exercise,but how this relates to future delirium is ***:Electrocardiogram data were examined in 38,740 middle-to older-aged UK Biobank participants(mean age=58.1 years,range:40-72 years;47.3%males)who completed a standardized submaximal exercise stress test(15-s baseline,6-min exercise,and 1-min recovery)and required hospitalization during *** HRR index was derived as the product of the heart rate(HR)responses during exercise(peak/resting HRs)and recovery(peak/recovery HRs)and categorized into low/average/high groups as the bottom quartile/middle 2 quartiles/top quartile,*** between 3 HRR groups and new-onset delirium were investigated using Cox proportional hazards models and a2-year landmark analysis to minimize reverse *** factors,lifestyle factors/physical activity,cardiovascular risk,comorbidities,cognition,and maximal workload achieved were included as ***:During a median follow-up period of 11 years,348 participants(9/1000)newly developed *** with the high HRR group(16/1000),the risk for delirium was almost doubled in those with low HRR(hazard ratio=1.90,95%)confidence interval(95%CI):1.30-2.79,p=0.001)and average HRR(hazard ratio=1.54,95%CI:1.07-2.22,p=0.020)).Low HRR was equivalent to being 6 years older,a current smoker,or>3 additional cardiovascular disease *** were robust in sensitivity analysis,but the risk appeared larger in those with better cognition and when only postoperative delirium was considered(n=1

关键词： Brain health Delirium Exercise stress test UK Biobank

Purification of Active Peroxidase Isoenzymes and Their Responses to Nitrogen Fertilization and Rotation of Biomass Sorghum

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American Journal of Plant Sciences 2012年第10期3卷 1422-1429页

作者： Jason P. Wight frank m. Hons Sanique m. South Godson O. Osuji Biotechnology and Biochemistry Laboratory CARC Prairie View A&M University Prairie View USA Department of Soil and Crop Sciences Texas A&M University College Station USA

Peroxidases (EC 1.***.1.7) participate in lignin biosynthesis. But peroxidation is not a tool for assaying lignocellulose metabolism because the active cannot yet be separated from the inactive peroxidases. A biochemical tool for assaying plant cell wall responses to agronomic practices is needed in the lignocellulosic feedstock renewable energy industry. Peroxidase of biomass sorghum was purified to 9 - 13 charge isomers by free solution IEF (Rotofor) technique. Free solution IEF was more effective than chromatographic purification of active peroxidase isoenzymes. Native PAGE separated each charge isomer to three anionic and three cationic isoenzymes. Hydrogen peroxide and o-dianisidine assays showed that only 20% - 30% of the isoenzymes displayed normal michaelis-menten kinetics. Sorghum planted without nitrogen fertilization induced the hydrogen peroxide noncompetitive inhibition of peroxidase, but 280 kg·ha–1 nitrogen fertilization and 100% sorghum mineral residue return to the soil tripled the concentration of active peroxidase and relieved the inhibition with concomitant increases of 350 kg lignin and 3532 kg·cellulose·ha–1. Nitrogen fertilization without crop rotation induced hydrogen peroxide inhibition of the peroxidase, but nitrogen fertilization and 25% sorghum rotation changed the PI of the active peroxidase from neutral to mildly acidic and relieved the inhibition with concomitant enormous increases of 690 kg lignin and 7151 kg·cellulose·ha–1. Hydrogen peroxide inhibition kinetics is consistent with the known peroxidase-substrate intermediate dead-end complex formation. Lignocellulosic yield was greatest under the agronomic management that combined 280 kg·ha–1 nitrogen fertilizer with 25% sorghum residue, which resulted in a shift of pI value of the active peroxidase due to a reduction in the Km value of the peroxidase. Therefore, up to 75% of sorghum biomass rather than only 50% can be harvested for conversion to bioenergy products.

关键词： Oxidoreduction Isoenzyme Patterns Inhibition by Hydrogen Peroxide Lignocellulose Yield Sorghum-Sorghum Rotation

Lipidomics reveals carnitine palmitoyltransferase 1C protects cancer cells from lipotoxicity and senescence

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Journal of Pharmaceutical Analysis 2021年第3期11卷 340-350页

作者： Huizhen Zhang Yongtao Wang Lihuan Guan Yixin Chen Panpan Chen Jiahong Sun frank J.Gonzalez min Huang Huichang Bi Guangdong Provincial Key Laboratory of New Drug Design and Evaluation School of Pharmaceutical SciencesSun Yat-Sen UniversityGuangzhou510006China Laboratory of metabolism Center for Cancer ResearchNational Cancer InstituteNational Institutes of HealthBethesdaMD20892USA

Lipotoxicity, caused by intracellular lipid accumulation, accelerates the degenerative process of cellular senescence, which has implications in cancer development and therapy. Previously, carnitine palmitoyltransferase 1C(CPT1C), a mitochondrial enzyme that catalyzes carnitinylation of fatty acids, was found to be a critical regulator of cancer cell senescence. However, whether loss of CPT1C could induce senescence as a result of lipotoxicity remains unknown. An LC/mS-based lipidomic analysis of PANC-1,mDA-mB-231, HCT-116 and A549 cancer cells was conducted after siRNA depletion of CPT1C. Cellular lipotoxicity was further confirmed by lipotoxicity assays. Significant changes were found in the lipidome of CPT1C-depleted cells, including major alterations in fatty acid, diacylglycerol, triacylglycerol, oxidative lipids, cardiolipin, phosphatidylglycerol, phosphatidylcholine/phosphatidylethanolamine ratio and sphingomyelin. This was coincident with changes in expressions of mRNAs involved in *** and biochemical analyses revealed higher lipid accumulation and increased malondialdehyde and reactive oxygen species, signatures of lipid peroxidation and oxidative stress. Reduction of ATP synthesis, loss of mitochondrial transmembrane potential and down-regulation of expression of mitochondriogenesis gene m RNAs indicated mitochondrial dysfunction induced by lipotoxicity, which could further result in cellular senescence. Taken together, this study demonstrated CPT1C plays a critical role in the regulation of cancer cell lipotoxicity and cell senescence, suggesting that inhibition of CPT1C may serve as a new therapeutic strategy through induction of tumor lipotoxicity and senescence.

关键词： Lipidomics Lipid accumulation Lipid peroxidation Oxidative stress mitochondrial dysfunction Anticancer target

Endoscopic ultrasonography-guided drainage for patients with symptomatic obstruction and enlargement of the pancreatic duct

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World Journal of Gastroenterology 2015年第46期21卷 13140-13151页

作者： Uwe Will Andreas Reichel frank Fueldner frank meyer Department of Internal medicine Ⅲ (Gastroenterology and Hepatology) Municipal Hospital (SRH Waldklinikum Gmb H) Department of General Abdominal and Vascular SurgeryUniversity Hospital

AIm: To evaluate the use of translumenal pancreatography with placement of endoscopic ultrasonography(EUS)-guided drainage of the pancreatic ***: This study enrolled all consecutive patients between June 2002 and April 2014 who underwent EUSguided pancreatography and subsequent placement of a drain and had symptomatic retention of fluid in the pancreatic duct after one or more previous unsuccessful attempts at endoscopic retrograde cannulation of the pancreatic duct. In all,94 patients underwent 111 interventions with one of three different approaches:(1) EUS-endoscopic retrograde drainage with a rendezvous technique;(2) EUS-guided drainage of the pancreatic duct; and(3) EUS-guided,internal,antegrade drainage of the pancreatic ***: The mean duration of the interventions was 21 min(range,15-69 min). mean patient age was 54 years(range,28-87 years); the m:F sex ratio was 60:34. The technical success rate was 100%,achieving puncture of the pancreatic duct including pancreatography in 94/94 patients. In patients requiring drainage,initial placement of a drain wassuccessful in 47/83 patients(56.6%). Of these,26 patients underwent transgastric/transbulbar positioning of a stent for retrograde drainage; plastic prostheses were used in 11 and metal stents in 12. A ring drain(antegrade internal drainage) was placed in three of these 26 patients because of anastomotic stenosis after a previous surgical intervention. The remaining 21 patients with successful drain placement had transpapillary drains using the rendezvous technique; the majority(n = 19) received plastic prostheses,and only two received metal stents(covered self-expanding metal stents). The median follow-up time in the 21 patients with transpapillary drainage was 28 mo(range,1-79 mo),while that of the 26 patients with successful transgastric/transduodenal drainage was 9.5 mo(range,1-82 mo). Clinical success,as indicated by reduced or absence of further pain after the EUS-guided intervention was

关键词： Endoscopic ultrasonography Endoscopic ultrasonogra

Diet high in fructose leads to an overexpression of lipocalin-2 in rat fatty liver

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World Journal of Gastroenterology 2014年第7期20卷 1807-1821页

作者： Salamah mohammad Alwahsh min Xu Hatice Ali Seyhan Shakil Ahmad Sabine mihm Giuliano Ramadori frank Christian Schultze Department of Gastroenterology and Endocrinology University Medical Center Goettingen37075 GoettingenGermany Department of General Visceral and Pediatric SurgeryUniversity Medical Center Goettingen37075 GoettingenGermany

AIm: To explore lipocalin-2 (LCN-2) expression and its possible role and mechanism(s) of production in rat models of diet-inducible fatty liver.

关键词： Non-alcoholic fatty liver disease Inflammation Endotoxins Lipopolysaccharide Oxidative stress mitochondrial dysfunction metabolic syndrome

6-相步光弹仪测试细纤维/树脂基体相界面剪应力

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江苏大学学报（自然科学版） 2010年第1期31卷 40-44页

作者：刘政袁新华 frank R Jones Ceramics and Composites Laboratory Department of Engineering MaterialsUniversity of Sheffield 江苏大学材料科学与工程学院江苏镇江212013

用新型的6-相步光弹仪,对直径25μm的单玻璃纤维增强环氧树脂复合材料的纤维-树脂相界面微观应力分布进行测试.相步弹性学分析表明纤维末端和纤维断裂处附近的等级条纹级数较高,存在较大的应力集中区域.试样两端加载18.38,25.61和32.53... 详细信息

用新型的6-相步光弹仪,对直径25μm的单玻璃纤维增强环氧树脂复合材料的纤维-树脂相界面微观应力分布进行测试.相步弹性学分析表明纤维末端和纤维断裂处附近的等级条纹级数较高,存在较大的应力集中区域.试样两端加载18.38,25.61和32.53mPa时,纤维末端相界面剪应力最大值分别出现在距纤维末端7,18和33μm处,为26.87,30.22和33.20mPa.纤维断裂处,加载为24.69mPa时,相界面剪应力最大值出现在距纤维断裂25μm处,约30mPa;加载增加到33.09mPa时,高的等级条纹级数区域向远离纤维断裂处延伸,相界面剪应力最大值增加到约36mPa.

关键词： 6-相步光弹仪相界面剪应力等级条纹级数等倾角

一种环境友好成膜型生物胶对蚊幼虫的杀灭作用（英文）

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中华卫生杀虫药械 2016年第5期22卷 421-426页

作者： frank k leung yirong song jing li phillip leung rose wang Waukegan illinois 60085U.S.A.

目的评估一种成膜型生物胶的物理特性、生物毒性,以及对水中蚊幼和蛹的杀灭作用。方法采用标准的药物毒理学模型鼠成纤维细胞进行毒性试验;利用人尿测试抗菌活性;采用100～1 000μm碳颗粒测试生物附着性与成膜的弹性;利用蚊幼和蚊蛹测... 详细信息

目的评估一种成膜型生物胶的物理特性、生物毒性,以及对水中蚊幼和蛹的杀灭作用。方法采用标准的药物毒理学模型鼠成纤维细胞进行毒性试验;利用人尿测试抗菌活性;采用100～1 000μm碳颗粒测试生物附着性与成膜的弹性;利用蚊幼和蚊蛹测试生物胶的灭蚊活性。结果该生物胶处理的大鼠成纤维细胞细胞正常生长,它对细胞染色质和细胞核无毒;它具有抗菌作用;该物质具有良好的成膜性,能够在数秒内形成塑料膜状的薄膜,且具有高弹性。一滴生物胶能够形成直径几英寸的膜。大力搅拌时,生物胶变成白色泡沫;该生物胶具有生物附着性,当生物胶形成的膜完全覆盖水面时,能够杀死100%的蚊子幼虫和蛹。结论这种生物胶具有易于使用,无毒,成膜快、环境友好的特点,完全覆盖水面后能够在24 h杀灭所有蚊幼虫和蛹。

关键词：成膜型生物胶环境友好无毒蚊幼虫新型蚊幼杀灭技术生物粘性膜