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journal of Materials Science & Technology 2019年第1期35卷 192-200页

作者： Q.Wen W.Y.Li W.B.Wang F.F.Wang Y.j.Gao V.patel State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding Technologies Northwestern Polytechnical University China FSW Center China Academy of Launch Vehicle Technology Beijing Institute of Astronautical Systems Engineering Capital Aerospace Machinery Company Pandit Deendayal Petroleum University

Stationary shoulder friction stir lap welding(SSFSLW) was employed to weld 2024 aluminum alloy. A coupled Eulerian-Lagrangian(CEL) model was developed to investigate the lap interface behavior during SSFSLW. Numerical results of material movement and equivalent plastic strain were in good agreement with the experimental work. With increasing welding speed, the distances from the hook tip to the top surface of the upper workpiece on the retreating side(RS) and the advancing side(AS) increase, while the distance between two wave-shaped alclads decreases. A symmetric interface bending is observed on the AS and the RS during plunging, while the interface bending on the AS is bigger than that on the RS during welding. The peak temperature of the interface on the AS is higher than that on the RS. The equivalent plastic strain gradually increases as the distance to the weld center decreases, and its peak value is obtained near the bottom of the weld.

关键词： Stationary shoulder friction stir lap welding Coupled Eulerian-Lagrangian Temperature field Material distribution Equivalent plastic strain

Use of doppler ultrasound to predict need for transjugular intrahepatic portosystemic shunt revision

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World journal of Hepatology 2022年第6期14卷 1200-1209页

作者： Nikki Duong Marcus Healey Kunal patel Brian j Strife Richard K Sterling Division of Gastroenterology Hepatologyand NutritionVirginia Commonwealth University Medical CenterRichmondVA 23219United States Department of Internal Medicine Virginia Commonwealth University Medical CenterRichmondVA 23219United States Division of Interventional Radiology Virginia Commonwealth University Medical CenterRichmondVA 23219United States

BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)is used to treat complications of portal hypertension,such as ascites and variceal bleeding(VB).While liver doppler ultrasound(DUS)is used to assess TIPS patency,trans-shunt venography(TSV)is the gold *** To determine the accuracy of DUS to assess TIPS dysfunction and for need for *** Retrospective review of patients referred for TIPS revision from ***,DUS parameters at baseline and at the DUS preceding TIPS revision,TSV data were *** operating characteristics curves,sensitivity,specificity,performance for doppler to predict need for revision were *** and multivariate analyses were used to predict clinical factors associated with need for TIPS *** The cohort consisted of 89 patients with cirrhosis(64%men,76%white,31%alcohol as etiology);median age 59 *** for initial TIPS were VB(41%),refractory ascites(51%),and other(8%).TIPS was revised in 44%.On univariate analysis,factors associated with need for TIPS revision were male(P=0.03),initial indication for TIPS(P=0.05)and indication for revision(P=0.01).Revision of TIPS was associated with lower mortality(26%vs 46%)and significantly lower rates of transplant(13%vs 24%;P=0.1).In predicting need for TIPS revision,DUS has a 40%sensitivity,45%specificity,PPV 78%,and NPV 14%.The most accurate location for shunt velocity measure was distal velocity(Area under the curve:0.79;P=0.0007).CONCLUSION DUS has poor overall sensitivity and specificity in predicting need for TIPS ***-invasive methods of predicting TIPS dysfunction are needed since those needing TIPS revision had better survival.

关键词： Transjugular intrahepatic portosystemic shunt Doppler ultrasound Portal hypertension

Development of an ionic polymer-metal composite stepper motor using a novel actuator model

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International journal of Smart and Nano Materials 2010年第4期1卷 261-277页

作者： A.j.McDaid K.C.Aw K.patel S.Q.Xie E.Haemmerle Department of Mechanical Engineering The University of AucklandNew Zealand

A novel ionic polymer–metal composite(IPMC)actuated stepper motor was developed in order to demonstrate an innovative design process for complete IPMC *** motor was developed by utilizing a novel model for IPMC actuators integrated with the complete mechanical model of the *** dynamic,nonlinear IPMC model can accurately predict the displacement and force actuation in air for a large range of input voltages as well as accounting for interactions with mechanical systems and external *** integrating this geometrically scalable IPMC model with a mechanical model of the motor mechanism an appropriate size IPMC strip has been chosen to achieve the required motor *** entire integrated system has been simulated and its performance *** system has been built and the experimental results validated to show that the motor works as simulated and can indeed achieve continuous 360rotation,similar to conventional *** has proven that the model is an indispensable design tool for integrated IPMC actuators into real *** newly developed system has demonstrated the complete design process for smart material actuator systems,representing a large step forward and aiding in the progression of IPMCs towards wide acceptance as replacements for traditional actuators.

关键词： ionic polymer-metal composite(IPMC) stepper motor mechanical design model application

Autologous treatment for ALS with implication for broad neuroprotection

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Translational Neurodegeneration 2022年第1期11卷 718-736页

作者： Daehwan Kim Subin Kim Ashley Sung Neetika patel Nathan Wong Michael j.Conboy Irina M.Conboy Department of Bioengineering and QB3 Institute University of CaliforniaBerkeleyCA 94720USA

Background: Amyotrophic lateral sclerosis (ALS) is characterized by a progressive loss of motor neurons (MNs), leading to paralysis, respiratory failure and death within 2-5 years of diagnosis. The exact mechanisms of sporadic ALS, which comprises 90% of all cases, remain unknown. In familial ALS, mutations in superoxide dismutase (SOD1) cause 10% of cases. Methods: ALS patient-derived human-induced pluripotent stem cells (ALS hiPSCs, harboring the SOD1AV4 mutation), were differentiated to MNs (ALS-MNs). The neuroprotective effects of conditioned medium (CM) of hESCs (H9), wt hiPSCs (WTC-11) and the ALS iPSCs, on MN apoptosis and viability, formation and maintenance of neurites, mitochon-drial activity and expression of inflammatory genes, were examined. For in vivo studies, 200 μl of CM from the ALS iPSCs (CS07 and CS053) was injected subcutaneously into the ALS model mice (transgenic for the human SOD1G93A mutation). Animal agility and strength, muscle innervation and mass, neurological score, onset of paralysis and lifes-pan of the ALS mice were assayed. After observing significant disease-modifying effects, the CM was characterized biochemically by fractionation, comparative proteomics, and epigenetic screens for the dependence on pluripotency. CM of fibroblasts that were differentiated from the wt hiPSCs lacked any neuroprotective activity and was used as a negative control throughout the studies. Results: The secretome of PSCs including the ALS patient iPSCs was neuroprotective in the H2O2 model. In the model with pathogenic SOD1 mutation, ALS iPSC-CM attenuated all examined hallmarks of ALS pathology, rescued human ALS-MNs from denervation and death, restored mitochondrial health, and reduced the expression of inflam-matory genes. The ALS iPSC-CM also improved neuro-muscular health and function, and delayed paralysis and mor-bidity in ALS mice. Compared side by side, cyclosporine (CsA), a mitochondrial membrane blocker that prevents the leakage of mitochondri

关键词： Neurodegeneration Amyotrophic lateral sclerosis SOD1 mutation Pluripotent stem cells Secretome

Multidrug resistance associated proteins in multidrug resistance

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Chinese journal of Cancer 2012年第2期31卷 58-72页

作者： Kamlesh Sodani Atish patel Rishil j.Kathawala Department of Pharmaceutical Sciences College of Pharmacy and Allied Health ProfessionsSt.John's UniversityQueensNY 11439USA

Multidrug resistance proteins(MRPs) are members of the C family of a group of proteins named ATP-binding cassette(ABC) *** ABC transporters together form the largest branch of proteins within the human *** MRP family comprises of 13 members,of which MRP1 to MRP9 are the major transporters indicated to cause multidrug resistance in tumor cells by extruding anticancer drugs out of the *** are mainly lipophilic anionic transporters and are reported to transport free or conjugates of glutathione(GSH),glucuronate,or *** addition,MRP1 to MRP3 can transport neutral organic drugs in free form in the presence of free ***,MRPs can transport drugs that differ structurally and mechanistically,including natural anticancer drugs,nucleoside analogs,antimetabolites,and tyrosine kinase *** of these MRPs transport physiologically important anions such as leukotriene C4,bilirubin glucuronide,and cyclic *** review focuses mainly on the physiological functions,cellular resistance characteristics,and probable in vivo role of MRP1 to MRP9.

关键词：多药耐药相关蛋白酪氨酸激酶抑制剂葡萄糖醛酸 MRPs 离子转运抗癌药物肿瘤细胞

Changes in macular thickness following glaucoma surgery

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International journal of Ophthalmology(English edition) 2016年第8期9卷 1236-1237页

作者： Priyamvada M. Pitale Usma Chatha Varun patel Lalita Gupta Michael Waisbourd Michael j Pro Glaucoma Research Center Wills Eye Hospital

Dear Sir,Previous reports have illustrated reversible structural changes in optic disc cupping,the lamina cribrosa,and the retinal nerve fiber layer(RNFL)following glaucoma surgery[1-3].However,few studies have assessed changes in macular thickness following such *** aim was to investigate the impact of intraocular pressure(IOP)reduction after glaucoma surgery on total macular thickness

关键词： IOP RNFL Changes in macular thickness following glaucoma surgery

Predictors of sperm recovery after cryopreservation n testicular cancer

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Asian journal of Andrology 2016年第1期18卷 35-38页

作者： james M Hotaling Darshan P patel Christopher Vendryes Natalya A Lopushnyan Angela P Presson Chong Zhang charles H Muller Thomas j Walsh Division of Urology Department of Surgery University of Utah Salt Lake City UT 84132 USA Department of Urology University of Illinois-Chicago Chicago IL 60612 USA Department of Urology University of Washington Seattle WA 98195 USA Division of Epidemiology Department of Internal Medicine University of Utah Salt Lake City UT 84132 USA

Our objective was to identify predictors of improved postthaw semen quality in men with testicular cancer banking sperm for fertility preservation. We reviewed 173 individual semen samples provided by 67 men with testicular germ cell tumor （TGCT） who cryopreserved sperm before gonadotoxic treatment between 1994 and 2010 at our tertiary university medical center. Our main outcomes measures were independent predictors for the greater postthaw total motile count （TMC） in men with TGCT. Men with NSGCT were more likely to be younger （P 〈 0.01） and had high cancer stage （Ⅱ or Ⅲ, P 〈 0.01） compared with men with seminoma. In our multiple regression model, NSGCT histology, use of density gradient purification, and fresh TMC 〉 median fresh TMC each had increased odds of a postthaw TMC greater than median postthaw TMC. Interestingly, age, advanced cancer stage （11 or III）, rapid freezing protocol, and motility enhancer did not show increased odds of improved postthaw TMC in our models. In conclusion, men with TGCT or poor fresh TMC should consider preserving additional vials （at least 15 vials） before oncologic treatment. Density gradient purification should be routinely used to optimize postthaw TMC in men with TGCT. Larger, randomized studies evaluating cancer stage and various cryopreservation techniques are needed to assist in counseling men with TGCT regarding fertility preservation and optimizing cryosurvival.

关键词： cryopreservation fertility preservation seminoma testicular neoplasms

Identification of Potential Species <i>Croton bonplandianum</i>, Sedges and <i>Balanitis aegyptiaca</i>for the Application of Phytoremediation

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American journal of Plant Sciences 2013年第6期4卷 1246-1251页

作者： pritesh Parmar Bhaumik Dave Ketankumar Panchal R. B. Subramanian B R D School of Biosciences Sardar Patel University Vallabh Vidya India.

Heavy metal contamination to the environment is a serious problem in the developing countries due to anthropogenic activities, a threat needs to remediate to sustain the life on earth, technology includes use of microorganisms and different plant species. In consideration of biomass, phytoremediation is a very useful techniques above all, can be exploit by identification of hyperaccumulator, which accumulates the heavy metal under metal stress condition. In view of constraints of efficient plant species in present study thirty seven different plant species were screened for the identification of heavy metal accumulators. Croton bonplandianum, sedges and Balanites aegyptiaca amongst the all exhibit superior potential of heavy metal accumulation. This is the first report to unravel the heavy metal accumulation property of three different plant species which can be exploited for the bioremediation of heavy metals.

关键词： Balanitis aegyptiaca Croton bonplandianum Hyperaccumulator Phytoremediation Screening Sedges

Counter-regulatory phosphatases TNAP and NPP1 temporally regulate tooth root cementogenesis

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International journal of Oral Science 2015年第1期7卷 27-41页

作者： Laura E Zweifler Mudita K patel Francisco H Nociti jr Helen F Wimer jose L Milln Martha j Somerman Brian L Foster National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) National Institutes of Health (NIH) Department of Prosthodontics and Periodontics Division of Periodontics School of Dentistry Campinas State University Department of Vertebrate Zoology National Museum of Natural History Smithsonian Institution Sanford Children’s Health Research Center Sanford-Burnham Medical Research Institute

Cementum is critical for anchoring the insertion of periodontal ligament fibers to the tooth root. Several aspects of cementogenesis remain unclear, including differences between acellular cementum and cellular cementum, and between cementum and bone. Biomineralization is regulated by the ratio of inorganic phosphate （Pi） to mineral inhibitor pyrophosphate （PPi）, where local Pi and PPi concentrations are controlled by phosphatases including tissue-nonspecific alkaline phosphatase （TNAP） and ectonucleotide pyrophosphatase/phosphodiesterase 1 （NPP1）. The focus of this study was to define the roles of these phosphatases in cementogenesis. TNAP was associated with earliest cementoblasts near forming acellular and cellular cementum. With loss of TNAP in the Alpl null mouse, acellular cementum was inhibited, while cellular cementum production increased, albeit as hypomineralized cementoid. In contrast, NPP1 was detected in cementoblasts after acellular cementum formation, and at low levels around cellular cementum. Loss of NPP1 in the Enppl null mouse increased acellular cementum, with little effect on cellular cementum. Developmental patterns were recapitulated in a mouse model for acellular cementum regeneration, with early TNAP expression and later NPP1 expression. In vitro, cementoblasts expressed Alpl gene/protein early, whereas Enppl gene/protein expression was significantly induced only under mineralization conditions. These patterns were confirmed in human teeth, including widespread TNAP, and NPP1 restricted to cementoblasts lining acellular cementum. These studies suggest that early TNAP expression creates a low PPi environment promoting acellular cementum initiation, while later NPP1 expression increases PPi, restricting acellular cementum apposition. Alterations in PPi have little effect on cellular cementum formation, though matrix mineralization is affected.

关键词： cementum bone ectonucleotide pyrophosphatase phosphodiesterase 1 periodontal ligament progressive ankylosis protein tissue-nonspecific ajkaljne phosphatase

High omega arachidonic acid/docosahexaenoic acid ratio induces mitochondrial dysfunction and altered lipid metabolism in human hepatoma cells

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World journal of Hepatology 2020年第3期12卷 84-98页

作者： Reem Ghazali Kosha j Mehta SW Annie Bligh Ihab Tewfik Dahn Clemens Vinood B patel School of Life Sciences University of WestminsterLondon W1W 6UWUnited Kingdom Clinical Biochemistry Department Faculty of medicineKing Abdulaziz UniversityJeddah 21589Saudi Arabia Centre for Education Faculty of Life Sciences and MedicineKing's College London SE11ULUnited Kingdom Caritas Institute of Higher Education Hong Kong 999077China Nebraska and Western Iowa Veterans Administration Medical Center and Department of Internal Medicine University of Nebraska Medical CenterOmahaNE 68198United States

BACKGROUND Non-alcoholic fatty liver disease(NAFLD) is a common cause of liver disease worldwide and is a growing epidemic. A high ratio of omega-6 fatty acids to omega-3 fatty acids in the diet has been implicated in the development of NAFLD. However, the inflicted cellular pathology remains unknown. A high ratio may promote lipogenic pathways and contribute to reactive oxygen species(ROS)-mediated damage, perhaps leading to mitochondrial ***, these parameters were investigated to understand their contribution to NAFLD *** To examine the effect of increasing ratios of omega-6:3 fatty acids on mitochondrial function and lipid metabolism *** Hep G2-derived VL-17 A cells were treated with normal(1:1, 4:1) and high(15:1,25:1) ratios of omega-6: omega-3 fatty acids [arachidonic acid(AA):docosahexaenoic acid(DHA)] at various time points. Mitochondrial activity and function were examined via MTT assay and Seahorse XF24 analyzer, *** accumulation was determined by using Enzy Chrom? and levels of ROS were measured by fluorescence intensity. Protein expression of the mediators of lipogenic, lipolytic and endocannabinoid pathways was assessed by Western *** High AA:DHA ratio decreased mitochondrial activity(P < 0.01;up to 80%) and promoted intracellular triglyceride accumulation(P < 0.05;40%-70%).Mechanistically, it altered the mediators of lipid metabolism;increased the expression of stearoyl-Co A desaturase(P < 0.05;22%-35%), decreased the expression of peroxisome proliferator-activated receptor-alpha(P < 0.05;30%-40%) and increased the expression of cannabinoid receptor 1(P < 0.05;31%).Furthermore, the high ratio increased ROS production(P < 0.01;74%-115%) and reduced mitochondrial respiratory functions such as basal and maximal respiration, ATP production, spare respiratory capacity and proton leak(P < 0.01;35%-68%).CONCLUSION High AA:DHA ratio induced triglyceride accumulation, increased oxida

关键词： Non-alcoholic fatty liver disease Lipogenesis Omega fatty acids Mitochondrial dysfunction Reactive oxygen species Oxidative stress