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Consistent constitutive modeling of metallic target penetration using empirical, analytical, and numerical penetration models

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defence Technology（防务技术） 2016年第2期12卷 201-213页

作者： John(Jack) P.RIEGEL iii david dAVISON R3 Technology Inc. 7324 Fountain Spring Ct. Shock Transients Inc.

Historically, there has been little correlation between the material properties used in(1) empirical formulae,(2) analytical formulations, and(3) numerical models. The various regressions and models may each provide excellent agreement for the depth of penetration into semi-infinite targets. But the input parameters for the empirically based procedures may have little in common with either the analytical model or the numerical model. This paper builds on previous work by Riegel and Anderson(2014) to show how the Effective Flow Stress(EFS) strength model, based on empirical data, can be used as the average flow stress in the analytical Walker–Anderson Penetration model(WAPEN)(Anderson and Walker,1991) and how the same value may be utilized as an effective von Mises yield strength in numerical hydrocode simulations to predict the depth of penetration for eroding projectiles at impact velocities in the mechanical response regime of the materials. The method has the benefit of allowing the three techniques(empirical, analytical, and numerical) to work in tandem. The empirical method can be used for many shot line calculations, but more advanced analytical or numerical models can be employed when necessary to address specific geometries such as edge effects or layering that are not treated by the simpler methods. developing complete constitutive relationships for a material can be costly. If the only concern is depth of penetration, such a level of detail may not be required. The effective flow stress can be determined from a small set of depth of penetration experiments in many cases, especially for long penetrators such as the L/d = 10 ones considered here, making it a very practical approach. In the process of performing this effort, the authors considered numerical simulations by other researchers based on the same set of experimental data that the authors used for their empirical and analytical assessment. The goals were to establish a baseline with a full constitut

关键词：本构模型渗透模型数值模型金属靶材料性质流动应力程序模拟数值计算

Quantification of the morphological transition in cadmium selenide nanocrystals as a function of reaction temperature

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Frontiers of Materials Science 2016年第1期10卷 8-14页

作者： Michael Tanner CAMERON Jordan A. ROGERSON douglas A. BLOM Albert d. dUKES iii department of Physical Sciences Lander University 320 Stanley Avenue CPO Box 6030 Greenwood SC 29649 USA NanoCenter and Electron Microscopy Center University of South Carolina Columbia SC 29208 USA

Controlling the morphology of semiconductor nanocrystals has typically relied on controlling the concentration and species of surface ligands utilized in synthesis. Specific shapes, such as branched structures are of particular interest as the light harvesting and charge separating layer in a photovoltaic device. In this work we quantify how changes in the reaction temperature affect the resulting morphology of the nanocrystals. The narrowness of the temperature range over which the morphological transition occurred provides guidance to the tolerances necessary in the synthesis of CdSe utilized in commercial devices on a large scale.

关键词： CdSe nanocrystals morphology control synthesis electron microscopy

Storylines of family medicine Ⅺ:professional identity formation—nurturing one’s own story

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Family Medicine and Community Health 2024年第S03期12卷 99-108页

作者： William B Ventres Leslie A Stone Hamish J Wilson Sumi M Sexton david J doukas Jessica P Cerdena david M Kelley Michael d Fetters Jeffrey J Haney John J Frey iii Family and Preventive Medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA General Practice and Rural Health University of Otago Dunedin School of MedicineDunedinNew Zealand Family Medicine Georgetown University School of MedicineWashingtonDistrict of ColumbiaUSA Family and Community Medicine Tulane University School of MedicineNew OrleansLouisianaUSA Family Medicine Residency Program Middlesex HealthMiddletownConnecticutUSA Family Medicine University of Michigan Medical SchoolAnn ArborMichiganUSA Medical Education and Clinical Sciences Washington State UniversitySpokaneWashingtonUSA Family Medicine and Community Health University of Wisconsin-Madison School of Medicine and Public HealthMadisonWisconsinUSA

Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅺ:professional identity formation—nurturing one’s own story’,authors address the following themes:‘The social construction of professional identity’,‘On becoming a family physician’,‘What’s on the test?—professionalism for family physicians’,‘The ugly doc-ling’,‘Teachers—the essence of who we are’,‘Family medicine research—it starts in the clinic’,‘Socially accountability in medical education’,‘Personal philosophy and how to find it’and‘Teaching and learning with Storylines of Family Medicine’.May these essays encourage readers to find their own creative spark in medicine.

关键词： own becoming professional

Investigating Physiological and Morphological Mechanisms of drought Tolerance in Wheat (<i>Triticum aestivum</i>L.) Lines with 1RS Translocation

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American Journal of Plant Sciences 2014年第13期5卷 1936-1944页

作者： david Karki William Wyant iii William A. Berzonsky Karl d. Glover Formerly Plant Science department South Dakota State University Brookings USA Plant Science department South Dakota State University Brookings USA

Rye (Secale cereale L.) chromosome translocation is reported to enhance yield attributes in common wheat (Triticum aestivum L.). We used 1RS translocations within the spring wheat cultivar “Pavon76” to measure and identify the translocation that is suitable to withstand moisture stress conditions without significant loss in yield potential. Four lines were grown under two water regimes in greenhouse environment in 2011 and 2012. The rye translocation increased root and shoot biomass in some cases, reduced plant height, and delayed maturity in some cases. The 1RS.1BL translocation produced the highest grain yield associated with the lowest root and shoot biomass under both well watered and water stressed conditions. Root and shoot biomass were recorded the highest for 1RS.1AL under well watered condition. However it produced the least biomass for both traits under water stressed conditions. In most cases, lines were not statistically differentiated for seminal root angle, abscisic acid concentration, water use efficiency, and grain yield. Results from our study show that the 1RS.1BL translocation is more suited to produce high grain yield under moisture limiting conditions.

关键词： Wheat Rye Translocation Chromosome Water Regime

Additive neurorestorative effects of exercise and docosahexaenoic acid intake in a mouse model of Parkinson’s disease

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Neural Regeneration Research 2025年第2期20卷 574-586页

作者： Olivier Kerdiles Méryl-Farelle Oye Mintsa Mi-mba Katherine Coulombe Cyntia Tremblay VincentÉmond Martine Saint-Pierre Clémence Rouxel Line Berthiaume Pierre Julien Francesca Cicchetti Frédéric Calon Facultéde pharmacie UniversitéLaval1050 Avenue de la MédecineQuebecQCCanada Axe Neuroscience Centre de recherche du CHU de Québec-UniversitéLaval(Pavillon CHUL)2705 Boulevard LaurierQuebecQCCanada Institute of Nutrition and Functional Foods QuebecQCCanada Optinutribrain International Associated Laboratory(NutriNeuro FranceINAFCanada)QuebecQCCanada Axe Endocrinologie et Néphrologie Centre de recherche du CHU de Québec-UniversitéLavalQuebecQCCanada département de Médecine Facultéde MédecineUniversitéLavalQuebecQCCanada département de Psychiatrie et Neurosciences Facultéde MédecineQuebecQCCanada

There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after *** that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic ***,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal *** weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 *** this period,the animals had access to a running wheel,which they could use or *** acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars ***,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned *** to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal dOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned *** present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease.

关键词： 6-hydroxydopamine dopamine dopamine transporter exercise neurorestoration Parkinson’s disease polyunsaturated fatty acids omega-3

Factors associated with increased incidence of severe toxicities following yttrium-90 resin microspheres in the treatment of hepatic malignancies

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World Journal of Gastroenterology 2016年第10期22卷 3006-3014页

作者： John d Roberson II Andrew M Mc donald Craig J Baden Chee Paul Lin Rojymon Jacob Omer L Burnett iii School of Medicine University of Alabama at Birmingham Birmingham AL 35294-3412 United States department of Radiation Oncology University of Alabama at Birmingham Birmingham AL 35233 United States Center for Clinical and Translational Science University of Alabama at Birmingham Birmingham AL 35205 United States

AIM: To further define variables associated with increased incidences of severe toxicities following administration of yttrium-90 (90Y) ***: Fifty-eight patients undergoing 79 treatments were retrospectively assessed for development of clinical and laboratory toxicity incidence following 90Y administration. Severe toxicity events were defined using Common Terminology Criteria for Adverse Events version 4.03 and defined as grade ≥ 3. Univariate logistic regression analyses were used to evaluate the effect of different factors on the incidence of severe toxicity events. Multicollinearity was assessed for all factors with P ded due to multicollinearity were included in a multivariate logistic regression model for each measurement of severe ***: Severe (grade ≥ 3) toxicities occurred following 21.5% of the 79 treatments included in our analysis. The most common severe laboratory toxicities were severe alkaline phosphatase (17.7%), albumin (12.7%), and total bilirubin (10.1%) toxicities. decreased pre-treatment albumin (OR = 26.2, P = 0.010) and increased pre-treatment international normalized ratio (INR) (OR = 17.7, P = 0.048) were associated with development of severe hepatic toxicity. Increased pre-treatment aspartate aminotransferase (AST; OR = 7.4, P = 0.025) and decreased pre-treatment hemoglobin (OR = 12.5, P = 0.025) were associated with severe albumin toxicity. Increasing pre-treatment model for end-stage liver disease (MELd) score (OR = 1.8, P = 0.033) was associated with severe total bilirubin toxicity. Colorectal adenocarcinoma histology was associated with severe alkaline phosphatase toxicity (OR = 5.4, P = 0.043).CONCLUSION: Clinicians should carefully consider pre-treatment albumin, INR, AST, hemoglobin, MELd, and colorectal histology when choosing appropriate candidates for 90Y microsphere therapy.

关键词： Yttrium-90 microspheres Liver metastases Multivariate analysis Toxicity incidence Colorectal adenocarcinoma

The Impact of Exchange Rate Volatility on Asset Returns in African Countries

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The Impact of Exchange Rate Volatility on Asset Returns in A...

作者： MAKON iii MARTIN 浙江工商大学

学位级别：硕士

本文研究了汇率波动对股票收益率和债券收益率的影响,以及埃塞俄比券亚、尼日利亚、坦桑尼亚、赞比亚和南非五个非洲经济体的外汇、股票和债市场之间的波动溢出。为了实现这一目标,我们使用了一个带有BEKK 数规范的多变量GARCH-M模型来... 详细信息

本文研究了汇率波动对股票收益率和债券收益率的影响,以及埃塞俄比券亚、尼日利亚、坦桑尼亚、赞比亚和南非五个非洲经济体的外汇、股票和债市场之间的波动溢出。为了实现这一目标,我们使用了一个带有BEKK 数规范的多变量GARCH-M模型来获取来自不同国家央行的每周数据汇率据来自不同央行而这些国家的金融市场则用于获取股票和债券的数债据数据分析的结果表明,汇率波动对我们样本中所有五个国家的十年期券收益都有较大影响,而南非除外,汇率波动具有负面此外,汇率波动对埃塞俄比亚,赞比亚和南非的股票收益率产生积极影响,而对尼日利亚和坦桑尼亚股票收益率的影响则为负值。这些结果表明,埃塞俄比亚、赞比亚和南非的股票收益率随着汇率波动的增加而上升尼日利亚和坦桑尼亚的股票收益率则随着汇率波动的减少而下降。此外,股票收益率,债券收益率和外汇市场之间的波动溢出结果表明,南非的波动是从资本市场向外汇市场传导的,而货币市场波动影响着坦桑尼亚的资本市场此研究结果为埃塞俄比亚和尼日利亚的双向波动传播提供了一些证据。令人惊讶的是,在赞比亚,波动从外汇市场传导到债券市场,而股票变化影响外汇市场。根据这些结果,我们建议所研究国家的货币当局采取有助于缓解本国货币波动的政策,以使资本在各自经济体的流入和流出趋于平稳,并降低投资者和各自经济体的波动成本。再者,一些旨在扩大可供投资者使用的金融工具和衍生工具,通过对冲汇率波动和对投资组合流动进行细致管理来降低风险的措施,也将具有极其重要的意义。

关键词：汇率资金流动 GARCH模型非洲溢出效应汇率波动

decreasing recurrent bowel obstructions,improving quality of life with physiotherapy:Controlled study

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World Journal of Gastroenterology 2018年第19期24卷 2108-2119页

作者： Amanda d Rice Kimberley Patterson Evette d Reed Belinda F Wurn Kristen Robles Bernhard Klingenberg Leonard B Weinstock Janey SA Pratt C Richard King iii Lawrence J Wurn department of Internal Medicine College of Medicine-PhoenixUniversity of ArizonaPhoenixAZ 85004United States Clear Passage Therapies GainesvilleFL 32606United States department of Mathematics and Statistics Williams CollegeWilliamstownMA 01267United States Clinical Medicine and Surgery Washington University School of MedicineSpecialists in GastroenterologyLLCSt.LouisMO 63141United States department of Surgery Stanford University School of MedicinePalo AltoCA 94035United States College of Medicine University of FloridaGainesvilleFL 32607United States

AIM To compare(1) quality of life and(2) rate of recurrent small bowel obstructions(SBO) for patients treated with novel manual physiotherapy vs no treatment. METHOdS One hundred and three subjects(age 19-89) with a history of recurrent adhesive SBO were treated with a manual physiotherapy called the Clear Passage Approach(CPA) which focused on decreasing adhesive crosslinking in abdominopelvic viscera. Pre-and post-therapy data measured recurring obstructions and quality of life, using a validated test sent 90 d after therapy. Results were compared to 136 untreated control subjects who underwent the same measurements for subjects who did not receive any therapy, which is the normal course for patients with recurring SBO. Comparison of the groups allowed us to assess changes when the physiotherapy was added as an adjunct treatment for patients with recurring *** despite histories of more prior hospitalizations, obstructions, surgeries, and years impacted by bowel issues, the 103 CPA-treated subjects reported a significantly lower rate of repeat SBO than 136 untreated controls(total obstructions P = 0.0003; partial obstructions P = 0.0076). Subjects treated with the therapy demonstrated significant improvements in five of six total domains in the validated Small Bowel Obstruction Questionnaire(SBO-Q). domains of diet, pain, gastrointestinal symptoms, quality of life(QOL) and pain severity when compared to post CPA treatment were significantly improved(P dication domain was not changed in the CPA treated group(P = 0.176).CONCLUSION CPA physical therapy was effective for patients with adhesive SBO with significantly lower recurrence rate, improvement in reported symptoms and overall quality of life of subjects.

关键词： Clear passage approach Manual therapy Physical therapy Small bowel obstructions Adhesions Physiotherapy Alternative therapy

Characterizing motor impulsivity of individuals classified as overweight to obese

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Sports Medicine and Health Science 2023年第4期5卷 314-318页

作者： Kyle d.Flack Robert E.Anderson iii Kylie F.McFee Bridgette T.day department of dietetics and Human Nutrition College of AgricultureUniversity of KentuckyLexingtonKYUSA

deficits in the impulse control system are an important predictor of energy intake and body *** classified as overweight to obese may possess these deficits as a general behavioral trait or they may be food*** present study assessed motor impulsivity(ability to suppress a pre-potent response)when presented with food and neutral(non-food)cues,testing if deficits in motor impulsivity is specific to food cues or a general trait among participants classified as overweight to *** proportion of inhibitory failures to no-go targets following food cues(10.8%)was significantly greater than the proportion of inhibitory failures to no-go targets following neutral cues(1.9%,pdifferences remained when covering for sex and *** indicates deficits in food-specific impulse control(as opposed to general impulse control)are present in those classified as overweight to *** the specific aspect of impulse control that is present in this population is needed for the development of future impulse control training interventions that seek to change eating behaviors as a means for weight control.

关键词： Impulsivity Inhibitory control Impulse control Response inhibition Food cues Obesity Go/NoGo task