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Tensile and cyclic deformation response of friction-stir-welded dissimilar aluminum alloy joints:Strain localization effect

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Journal of Materials Science & Technology 2021年第14期73卷 91-100页

作者： P.l.Niu W.Y.li d.l.Chen State Key laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding TechnologiesNorthwestern Polytechnical UniversityXi'an710072.China department of Mechanical and Industrial Engineering Ryerson University350 Victoria StreetTorontoOntarioM5B2K3Canada

Cyclic deformation behavior of friction-stir-welded dissimilar AA2024-T351 to AA7075-T65 aluminum alloy joints was evaluated via stepwise tests at different strain rates,along with transmission electron microscopy examinations to characterize the precipitates required to assess internal *** backscatter diffraction was employed to observe the inhomogeneous microstructures of the FSWed *** localization appeared in the heat affected zone(HAZ)of AA2024 *** cyclic deformation of 500 cycles at a total strain amplitude of 0.5%,the strength of the dissimilar joints resumed basically to that of AA2024 base *** the AA2024 HAZ was obviously hardened,which should be attributed to the introduced dislocations during cyclic deformation *** hardening capacity of the joints increased with decreasing strain rate.

关键词： Friction stir welding dissimilar aluminum alloys Strain localization Cyclic hardening Slip irreversibility

Alcohol-induced protein hyperacetylation: Mechanisms and consequences

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World Journal of Gastroenterology 2009年第10期15卷 1219-1230页

作者： Blythe d Shepard Pamela l Tuma department of Biology The Catholic University of America 620 Michigan Avenue NE Washington DC 20064 United States

Although the clinical manifestations of alcoholic liver disease are well-described, little is known about the molecular basis of liver injury. Recent studies have indicated that ethanol exposure induces global protein hyperacetylationo This reversible, post- translational modification on the E-amino groups of lysine residues has been shown to modulate multiple, diverse cellular processes ranging from transcriptional activation to microtubule stability. Thus, alcohol- induced protein hyperacetylation likely leads to major physiological consequences that contribute to alcohol-induced hepatotoxicity. lysine acetylation is controlled by the activities of two opposing enzymes, histone acetyltransferases and histone deacetylases. Currently, efforts are aimed at determining which enzymes are responsible for the increased acetylation of specific substrates. However, the greater challenge will be to determine the physiological ramifications of protein hyperacetylation and how they might contribute to the progression of liver disease. In this review, we will first list and discuss the proteins known to be hyperacetylated in the presence of ethanol. We will then describe what is known about the mechanisms leading to increased protein acetylation and how hyperacetylation may perturb hepatic function.

关键词： Ethanol Hepatotoxicity Acetylation deacetylases Acetyltransferases

Alcohol-induced alterations of the hepatocyte cytoskeleton

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World Journal of Gastroenterology 2010年第11期16卷 1358-1365页

作者： Blythe d Shepard Pamela l Tuma department of Biology The Catholic University of America

The hepatocyte cytoskeleton consists of three fi lamentous networks: microtubules, actin microfi laments and keratin intermediate filaments. Because of the abundance of the proteins that comprise each system and the central role each network plays in a variety of cellular processes, the three fi lament systems have been the focus of a host of studies aimed at understanding the progression of alcohol-induced liver injury. In this review, we will briefly discuss the hepatic organization of each cytoskeletal network and highlight some components of each system. We will also describe what is known about ethanol-induced changes in the dynamics and distributions of each cytoskeletal system and discuss what is known about changes in protein expression levels and post-translational modifi cations. Finally, we will describe the possible consequences of these cytoskeletal alterations on hepatocyte function and how they might contribute to the progression of liver disease.

关键词： Ethanol Hepatotoxicity Tubulin Actin Keratin

Factors associated with refractory pain in emergency patients admitted to emergency general surgery

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World Journal of Emergency Medicine 2021年第1期12卷 12-17页

作者： William Gilliam Jackson FBarr brandon Bruns brandon Cave Jordan Mitchell Tina Nguyen Jamie Palmer Mark Rose Safura Tanveer Chris Yum Quincy K.Tran Johns Hopkins University Baltimore 21218USA Research Associate Program in Emergency Medicine and Critical Care Department of Emergency MedicineUniversity of Maryland School of MedicineBaltimore 21201USA R Adams Cowley Shock Trauma Center University of Maryland School of MedicineBaltimore 21201USA department of Surgery University of Maryland School of MedicineBaltimore 21201USA louisiana State University Louisiana 70803USA University of Maryland School of Medicine Baltimore 21201USA department of Emergency Medicine University of Maryland School of MedicineBaltimore 21201USA

BACKGROUNd: Oligoanalgesia in emergency departments (Eds) is multifactorial. A previousstudy reported that emergency providers did not adequately manage patients with severe paindespite objective findings for surgical pathologies. Our study aims to investigate clinical andlaboratory factors, in addition to providers’ interventions, that might have been associated witholigoanalgesia in a group of Ed patients with moderate and severe pains due to surgical ***: We conducted a retrospective study of adult patients who were transferred directlyfrom referring Eds to the emergency general surgery (EGS) service at a quaternary academic centerbetween January 2014 and december 2016. Patients who were intubated, did not have adequaterecords, or had mild pain were excluded. The primary outcome was refractory pain, which wasdefi ned as pain reduction le between triage and Ed ***: We analyzed 200 patients, and 58 (29%) had refractory pain. Patients with refractory painhad signifi cantly higher disease severity, serum lactate (3.4±2.0 mg/dl vs. 1.4±0.9 mg/dl, P=0.001), and lessfrequent pain medication administration (median [interquartile range], 3 [3–5] vs. 4 [3–7], P=0.001), whencompared to patients with no refractory pain. Multivariable logistic regression showed that the number of painmedication administration (odds ratio [OR] 0.80, 95% confi dence interval [95% CI] 0.68–0.98) and Ed serumlactate levels (OR 3.80, 95% CI 2.10–6.80) were signifi cantly associated with the likelihood of refractory ***: In Ed patients transferring to EGS service, elevated serum lactate levelswere associated with a higher likelihood of refractory pain.

关键词： Serum lactate Refractory pain Emergency general surgery Emergency department

Effect of friction on corrosion behaviors of AISI 304 and Cr26Mo1 stainless steels in different solutions

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Journal of Iron and Steel Research International 2023年第12期30卷 2541-2556页

作者： Z.X.dai S.l.Jiang l.K.Ning X.d.Xu S.li d.l.duan Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026AnhuiChina liaoning Key laboratory of Aero-engine Materials Tribology Institute of Metal ResearchChinese Academy of SciencesShenyang110016LiaoningChina AnSteel lISCO Stainless Steel Co. Ltd.Guangzhou510760GuangdongChina

The corrosion and tribocorrosion behaviors of AISI 304 austenitic stainless steel and Cr26Mo1 ultrapure high chromium ferrite stainless steel in 3.5 wt.%NaCl and 0.5 mol/l H2SO4 solutions were *** electrochemical measurement technology was applied to identify electrochemistry behaviors during tribocorrosion tests in *** surface morphologies and compositions of the wear tracks were analyzed by scanning electron microscopy and Raman *** results showed that compositions of stainless steels,corrosive mediums and applied loads have great influence on tribocorrosion behaviors of stainless ***,the corrosion resistance in static state of stainless steels primarily dominates its tribocorrosion behavior;meanwhile,better mechanical properties are in favor of tribocorrosion ***,the corrosion rate is promoted significantly in 3.5%NaCl solution by friction,while the tendency is inconspicuous in 0.5 mol/l H2SO4 *** but not least,passive films on stainless steels can be wiped off by small friction *** the increase in applied load,the effect of friction converts to forming friction oxide film from removing passivation film,so that a critical load exists below which the friction force can promote the corrosion process extremely.

关键词： Tribocorrosion Stainless steel/PEEK friction pair Corrosive medium Applied load Microelectrode probe

Evaluating information-seeking approaches to metacognition

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Current Zoology 2011年第4期57卷 531-542页

作者： Jonathon d. CRYSTAl Allison l. FOOTE department of Psychological and Brain Sciences Indiana University Bloomington IN 47405 USA department of Psychology University of Georgia Athens GA 30602 USA

Metacognition has been divided into information monitoring and control processes. Monitoring involves knowing that you know or do not know some information without taking corrective action. Control involves taking corrective action based on the knowledge that you know or do not know some information. In comparative metacognition, considerable attention has been paid toward critically assessing putative evidence for information monitoring in non-human animals. However, less attention has been paid toward critically evaluating evidence for control processes in animals. We briefly review a critique of information-monitoring in animals. Next, we apply these concepts to a number of studies that focus on information seeking in animals. The main type of evidence for control processes in animals come from tube tipping experiments. Before having the opportunity to search for the bait in these experiments, the subject sometimes observes opaque tubes being baited but is sometimes prevented from seeing the baiting. The observations that the subjects look more if baiting was not seen and are more accurate if baiting was seen have been taken as evidence for metacognition in information-seeking experiments. We propose simple alternative hypotheses that are sufficient to explain putative evidence for information seeking in animals without positing metacognition. The alternative explanation focuses on two relatively simple principles： First, an animal has a default ＂look before you go＂ response which supersedes random searches in space. Second, spatially guided behavior follows a default rule of ＂go where something good is.＂ These principles can explain the results of tube tipping experiments without proposing metacognition [Current Zoology 57 （4）： 531-542, 2011].

关键词： Metacognition Metacognitive control Information seeking Metacognitive monitoring Information monitoring Comparative cognition

Influence of an External dC Electric Current on Plasma Cleaning Rate: an Application on the Enlarged Plasma-Surface Theor

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Plasma Science and Technology 2013年第5期15卷 448-454页

作者： Constantine l. XAPlANTERIS Eleni d. FIlIPPAKI Plasma Physics lab IMS NCSR "Demokritos" Hellenic Military Academy

during the last decades many researchers have been occupied with other plasma applications apart from the big challenge which the thermonuclear fusion poses. Many experiments have been carried out on the plasma behavior in contact with a solid surface; when the surface material consists of chemical compounds （e.g. oxides of metals）, then the plasma chemistry takes place. The present paper contains the final experimental and theoretical work of Plasma laboratory at ＂demokritos＂, which consists of an elaboration of plasma sheath parameters adapted to experimental conditions, a suitable choice of plasma gases （either H 2 or N 2 ）, and an electric po-tential current enforcement on objects. Additionally, a brief theory is given to explain the results, with a short reference to both boundary phenomena in thermonuclear reactors and low pressure plasma of glow discharges, so as to reveal the similarities and differences of these two cases. An extensive examination of the treated objects by X-ray diffraction method （XRd） gives results in agreement with the theoretical predictions. Using this improvement on plasma restoration system, （a combination of electric current on metallic object into suitable plasma）, it is shown that better results can be achieved on the cleaning and conservation of archaeological objects.

关键词： impurities plasma sheath parameters reduction of surfaces external poten-tial treatment rate

Effects of medium chain triglycerides on hepatic fatty acid oxidation in clofibrate-fed newborn piglets

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Animal Nutrition 2023年第1期12卷 334-344页

作者： Jinan Zhao brandon Pike Jin Huang Zhihua Feng Jack Odle Xi lin laboratory of developmental Nutrition Department of Animal SciencesNorth Carolina State UniversityRaleighNC 27695USA Zinpro Corporation Eden PrairieMN 55344USA College of Biological Engineering Henan University of TechnologyZhengzhou450001China College of Animal Science and Technology Agricultural University of HebeiBaoding071001China

To investigate whether increasing tricarboxylic acid(TCA)cycle activity and ketogenic capacity would augment fatty acid(FA)oxidation induced by the peroxisome proliferator-activated receptor-alpha(PPARα)agonist clofibrate,suckling newborn piglets(n=54)were assigned to 8 groups following a 2(±clofibrate)×4(glycerol succinate[SUC],triglycerides of 2-methylpentanoic acid[T2M],valeric acid[TC5]and hexanoic acid[TC6])factorial *** group was fed an isocaloric milk formula containing either 0%or 0.35%clofibrate(wt/wt,dry matter basis)with 5%SUC,T2M,TC5 or TC6 for 5 *** 6 pigs served as newborn *** acid oxidation was examined in fresh homogenates of liver collected on d 6 using[1-^(14)C]palmitic acid(1 mM)as a substrate(0.265μCi/μmol).Measurements were performed in the absence or presence of l-carnitine(1 mM)or inhibitors of 3-hydroxy-3-methylglutaryl-CoA synthase(l659699,1.6μM)or acetoacetate-CoA deacylase(iodoacetamide,50μM).Without clofibrate stimulation,^(14)C accumulation in CO_(2) was higher from piglets fed diets containing T2M and TC5 than SUC,but similar to those fed *** clofibrate stimulation,accumulation also was higher in homogenates from piglets fed TC5 than all other dietary *** between clofibrate and carnitine or the inhibitors were observed(P=0.0004)for acid soluble products(ASP).In vitro addition of carnitine increased^(14)C-ASP(Pll other treatments,regardless of clofibrate *** percentage of^(14)C in CO_(2) was higher(P=0.0023)in TC5 than in the control *** these results we suggest that dietary supplementation of anaplerotic and ketogenic FA could impact FA oxidation and modify the metabolism of acetyl-CoA(product ofβ-oxidation)via alteration of TCA cycle activity,but the modification has no significant impact on the hepatic FA oxidative capacity induced by PPARα.In addition,the availability of carnitine is a critical element to maintain FA oxidation during the neonatal perio

关键词： PPARα Clofibrate Newborn piglets Medium chain triglyceride(MCT) Hepatic fatty acid oxidation

Evaluation of effects of 1,3-dinitrobenzene on sperm motility of hamster using computer assisted semen analysis (CASA)

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Asian Journal of Andrology 2001年第2期3卷 109-114页

作者： l.d.C.Peiris H.d.M.Moore dept. of Zoology University of Colombo Colombo 03 Sri LankaDept. of Molecular Biology and Biotechnology University of Sheffield Sheffield S 10 2TN UK

Aim: To evaluate the effects of 1,3-dinitrobenznene (mdNB) on sperm motility of hamster and to correlate the re-sults with the fertility. Methods: Adult male hamsters were gavaged with one of the 3 dose regimes of mdNB(1.5 mg daily for 4 weeks ,1.5 mg one day a week for 4 weeks and 1.0 mg 3 days a week for 4 weeks). Computerassisted semen analysis (CASA) was used to analyse the sperm motility parameters, curvilinear velocity (VCl) andstraight line velocity (VSl) of sperm in distal corpus epididymides and distal cauda epididymides. In vitro fertilisationwas carried out only for 1.5 mg mdNB daily group to determine the sperm fertilising capacity. Results: There wasa significant reduction in sperm velocity parameters at weeks 3 and 4 after treatment, which was correlated with a de-cline in sperm fertility. Conclusion; Sperm velocity parameters may be used to determine the effect of a toxic insulton the sperm function.

关键词： mdNB sperm motility CASA sperm fertility