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Timing of Proterozoic magmatism in the Sunsas belt, Bolivian Precambrian Shield, SW Amazonian Craton

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Geoscience Frontiers 2021年第6期12卷 277-293页

作者： Ingrid m.Nedel Reinhardt A.Fuck Amarildo S.Ruiz Gerardo R.matos-Salinas Alanielson da C.D.ferreira Instituto de Geociências Universidade de Brasília(UnB)Brasília-DFBrazil Faculdade de Geociências Universidade Federal de Mato GrossoCuiabá-MTBrazil Instituto de Investigaciones Geológicas y del medio Ambiente Universidad Mayor de San Andrés(UMSA)Pabellón GeologíaCalle 27Campus Universitario Cota CotaLa PazBolivia Department of Earth Sciences Stellenbosch UniversityPrivate Bag X1Matieland7602 StellenboschSouth Africa

We present new U–Pb zircon and monazite ages from the Sunsas belt granitic magmatism in Bolivia, SW Amazonian Craton. The geochronological results revealed four major magmatic events recorded along the Sunsas belt domains. The older igneous event formed a granitic basement coeval to the Rio Apa Terrane(1.95–1.85 Ga) in the southern domain. The second magmatic episode is represented by 1.68 Ga granites associated to the Paraguá Terrane(1.69–1.66 Ga) in the northern domain. The 1.37–1.34 Ga granites related to San Ignacio orogeny represent the third and more pervasive magmatic event, recorded throughout the Sunsas belt. moreover, magmatic ages of ~1.42 Ga revealed that the granitogenesis associated to the Santa Helena orogeny also affected the Sunsas belt, indicating that it was not restricted to the Jauru Terrane. Lastly, the 1.10–1.04 Ga youngest magmatism was developed during the Sunsas orogeny and represents the final magmatic evolution related to Rodinia assembly. Likewise, the 1.95–1.85 and 1.68 Ga inherited zircon cores obtained in the ~1.3 Ga and 1.0 Ga granite samples suggest strong partial melting of the Paleoproterozoic sources. The 1079 ± 14 ma and 1018 ± 6 ma monazite crystallization ages can be correlated to the collisional tectono-thermal event of the Sunsas orogeny, associated to reactions of medium-to high-grade metamorphism. Thus, the Sunsas belt was built by heterogeneous 1.95–1.85 Ga and 1.68 Ga crustal fragments that were reworked at 1.37–1.34 Ga and 1.10–1.04 Ga related to orogenic collages. Furthermore, the 1.01 Ga monazite age suggests that granites previously dated by zircon can bear evidence of a younger thermal history. Therefore, the geochronological evolution of the Sunsas belt may have been more complex than previously thought.

关键词： SW Amazonian Craton Sunsas belt U–Pb geochronology Zircon monazite

Comparison of different statistical approaches to evaluate morphometric sperm subpopulations in men

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Asian Journal of Andrology 2016年第6期18卷 819-823页

作者： Jesus L Yaniz sandra Vicente-Fiel Caries Soler Pilar Recreo Teresa Carretero Araceli Bono Jose m Berne Pilar Santolaria TECNOGAm research group Environmental Sciences Institute (IUCA) Department of Animal Production and Food Sciences Higher Polytechnic School University of Zaragoza Ctra. Cuarte S/N 22071 Huesca Spain Department of Functional Biology and Physical Anthropology University of Valencia 46100 Burjassot Valencia Spain R+D Department Proiser R+D Scientific Park University of Valencia 46980 Paterna Valencia Spain TECNOGAm research group Environmental Sciences Institute (IUCA) Departament of Human Anatomy and Histology Faculty of Health and Sport Sciences of Huesca Plaza Universidad 3 22002 Huesca Spain TECNOGAm research group Environmental Sciences Institute (IUCA) Hospital General San Jorge de Huesca Area de Urologla Av. Martfnez de Velasco 36 22004 Huesca Spain

This study was designed to characterize morphometric sperm subpopulations in normozoospermic men by using different statistical methods and examining their suitability to classify correctly different sperm nuclear morphologies present in human ejaculates. Ejaculates from 21 normozoospermic men were collected for the study. After semen collection and analysis, samples were prepared for morphometric determination. At least 200 spermatozoa per sample were assessed for sperm morphometry by computer-assisted sperm morphometry analysis （CASA-morph） using fluorescence. Clustering and discriminant procedures were performed to identify sperm subpopulations from the morphometric data obtained. Clustering procedures resulted in the classification of spermatozoa into three morphometric subpopulations （large-round 30.4%, small-round 46.6%, and large-elongated 22.9%）. In the second analysis, using discriminant methods, the classification was made independently of size and shape. Three morphological categories according to nuclear size （small 〈10.90 μm^2, intermediate 10.91-13.07 μm^2, and large 〉13.07 μm^2） and four categories were defined on 400 canonical cells （100 × 4） from 10 men according to sperm nuclear shape （oval, pyriform, round, and elongated）. Thereafter, the resulting classification functions were used to categorize 4200 spermatozoa from 21 men. Differences in the class distribution were observed among men from both clustering and discriminant procedures. It was concluded that the combination of CASA-morph fluorescence-based technology with multivariate cluster or discriminant analyses provides new information on the description of different morphometric sperm subpopulations in normal individuals, and that important variations in the distribution of morphometric sperm subpopulations may exist between men, with possible functional implications.

关键词： computer-assisted sperm morphometry analysis man sperm subpopulations

Synthesis and characterization of nano-hydroxyapatite added with magnesium obtained by wet chemical precipitation

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Progress in Natural Science:materials International 2021年第4期31卷 575-582页

作者： Brandon A.Correa-Pi?a Omar m.Gomez-Vazquez sandra m.Londo?o-Restrepo Luis F.Zubieta-Otero Beatriz m.millan-malo mario E.Rodriguez-García Posgrado en Ciencia e Ingeniería de materiales Centro de Física Aplicada y Tecnología Avanzada Universidad Nacional Autónoma de México Campus Juriquilla Departamento de Nanotecnología Centro de Física Aplicada y Tecnología Avanzada Universidad Nacional Autónoma de México Campus Juriquilla

Biogenic hydroxyapatites from mammalian bones naturally contain traces of ions, like mg, which play a vital role in the bone remodeling process. In this way, synthetic hydroxyapatites should include this kind of mineral. In this work, hydroxyapatite added with mg was synthesized by wet precipitation using（NH;）H;PO;, Ca（NO;）;.4 H;O,and mg（NO;）;.6 H;O（0, 0.032, 0.061, and 0.123 m）. Inductively coupled plasma and X-ray diffraction evidenced the mg inclusion in the hydroxyapatite lattice in the same levels reported for natural hydroxyapatites. The calcination at 600℃ was performed to remove the reaction by-products, but it also gave rise to physicochemical changes as the coalescence and crystals recrystallization. It produced, in turn, an improvement in the crystalline quality, according to Raman analysis. Despite those physicochemical changes, all the samples remained nanometric according to scanning electron microscopy imaging.

关键词： magnesium Physicochemical properties Calcination Nanometric crystal size Coalescence Recrystallization

Contribution of inrush current to mechanical failure of power transformers windings

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High Voltage 2019年第4期4卷 300-307页

作者： Rafael m.R.Barros Edson Gda Costa Jalberth F.Araujo Filipe L.mde Andrade Tarso V.ferreira Department of Electrical Engineering Federal University of Campina GrandeAprigio Veloso St.882Campina GrandeBrazil

This work presents a study regarding the contribution of inrush current to the occurrence of mechanical fatigue in windings of a power transformer and,consequently,the impact of that phenomenon on the equipment's *** order to perform the study,electromagnetic transient simulations were used to determine the inrush current in a three-phase transformer ***,three-dimensional simulations,based on the finite element method,were performed to determine the electromechanical stresses in the equipment windings,under the effect of the inrush ***,the methods of critical plans and Palmgren–miner were applied to perform the fatigue *** the results,the impact of inrush current on the integrity of the transformer's windings was determined,as well as,to estimate the reduction of lifespan of the equipment due to inrush *** number of inrushes needed for the total reduction of lifespan of the equipment due to mechanical fatigue was also *** results can be used in the transformers design stage,with the purpose of assisting the evaluation of mechanical withstand of equipment,which can minimise the possibility of failure and increase its lifespan.

关键词： winding fatigue power

Assessment of conventional and air-jet wheel deflectors for drag reduction of the DrivAer model

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Advances in Aerodynamics 2021年第1期3卷 512-539页

作者： Kaloki L.Nabutola sandra K.S.Boetcher Department of mechanical Engineering Embry-Riddle Aeronautical UniversityDaytona BeachFLUSA

Aerodynamic drag is a large resistance force to vehicle motion,particularly at highway *** wheel deflectors were designed to reduce the wheel drag and,consequently,the overall vehicle drag;however,they may actually be detrimental to vehicle aerodynamics in modern *** the present study,computational fluid dynamics simulations were conducted on the notchback DrivAer model-a simplified,yet realistic,open-source vehicle model that incorporates features of a modern passenger *** and air-jet wheel deflectors upstream of the front wheels were introduced to assess the effect of underbody-flow deflection on the vehicle *** wheel-deflector designs with varying heights were observed and compared to 45◦and 90◦air-jet wheel *** conventional wheel deflectors reduced wheel drag but resulted in an overall drag increase of up to 10%.For the cases studied,the 90◦air jet did not reduce the overall drag compared to the baseline case;the 45◦air jet presented drag benefits of up to 1.5%at 35 m/s and *** to conventional wheel deflectors,air-jet wheel deflectors have the potential to reduce vehicle drag to a greater extent and present the benefit of being turned off at lower speeds when flow deflection is undesirable,thus improving efficiency and reducing emissions.

关键词： Vehicle aerodynamics Wheel and wheelhouse aerodynamics Automotive Active flow control Passive flow control DrivAer

Osteogenic differentiation of encapsulated cells in dexamethasone-loaded phospholipid-induced silk fibroin hydrogels

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Biomaterials Translational 2022年第3期3卷 213-220页

作者： Chavee Laomeephol Helena ferreira Sorada Kanokpanont Jittima Amie Luckanagul Nuno m Neves Siriporn Damrongsakkul Department of Pharmaceutics and Industrial Pharmacy Faculty of Pharmaceutical SciencesChulalongkorn UniversityBangkokThailand Biomaterial Engineering for medical and Health Research Unit Chulalongkorn UniversityBangkokThailand B’s Research Group I3Bs-Research Institute on BiomaterialsBiodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineGuimarãesPortugal ICVS/3B’s-PT Government Associate Laboratory Braga/GuimarãesPortugal Department of Chemical Engineering Faculty of EngineeringChulalongkorn UniversityBangkokThailand Biomedical Engineering Research Center Faculty of EngineeringChulalongkorn UniversityBangkokThailand Center of Excellence in Plant-produced Pharmaceuticals Chulalongkorn UniversityBangkokThailand

The tissue engineering triad comprises the combination of cells,scaffolds and biological ***,we prepared cell-and drug-loaded hydrogels using in situ silk fibroin(SF)hydrogels induced by dimyristoyl glycerophosphoglycerol(DmPG).DmPG is reported to induce rapid hydrogel formation by SF,facilitating cell encapsulation in the hydrogel matrix while maintaining high cell viability and proliferative *** addition,DmPG can be used for liposome formulations in entrapping drug ***(Dex)was loaded into the DmPG-induced SF hydrogels together with human osteoblast-like SaOS-2 cells,then the osteogenic differentiation of the entrapped cells was evaluated in vitro and compared to cells cultured under standard *** production by cells cultured in DmPG/Dex-SF hydrogels with Dex-depleted osteogenic medium was equivalent to that of cells cultured in conventional osteogenic medium containing *** extended-release of the entrapped Dex by the hydrogels was able to provide a sufficient drug amount for osteogenic *** controlled release of Dex was also advantageous for cell viability even though its dose in the hydrogels was far higher than that in osteogenic *** results confirmed the possibility of using DmPG-induced SF hydrogels to enable dual cell and drug encapsulation to fulfil the practical applications of tissue-engineered constructs.

关键词： DmPG osteogenic differentiation silk fibroin three-dimensional cell culture tissue engineering

mating Disruption of Striped Rice Stem Borer: Importance of Early Deployment of Dispensers and Impact on Airborne Pheromone Concentration

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Rice science 2021年第6期28卷 525-528,I0027-I0029页

作者： Aitor GAVARA sandra VACAS Jaime PRImO Vicente NAVARRO-LLOPIS Centre for Agricultural Chemical Ecology Mediterranean Agroforestry InstitutePolytechnic University of ValenciaBuilding 6CCamino de Vera s/n46022 ValenciaSpain

mating disruption(mD)is an effective environmentally-friendly control method against the striped rice stem borer(RSB),Chilo suppressalis(Lepidoptera:Crambidae).In this study,the current mD dispensers release the pheromone exponentially,with higher initial release rates that decrease throughout the *** adjust the timing of dispensers'deployment and evaluate the importance of controlling the early first or the second male flight,field trials were carried out to test the efficacy of two strategies:the early dispenser deployment prior to the first male flight(may)and the late deployment prior to the second flight(June).The early dispenser deployment was more effective in reducing plant damage inflicted by RSB when assessed at ***,neither of these strategies was able to inhibit the male catches of the third flight due to the dispensers5 *** to the airborne pheromone concentrations obtained,around 1.60 ng/m3 were capable to inhib社*** male flight effectively.

关键词： release Impact adjust

Associations between extracurricular activity participation and health-related variables in underrepresented children

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Sports medicine and Health Science 2020年第2期2卷 102-108页

作者： Jeanette m.Ricci Kimberly A.Clevenger sandra Sellers Sharon Davenport Karin A.Pfeiffer michigan State University 308 W Circle DrEast LansingMI48823USA Crim Fitness Foundation 452 S.Saginaw StSuite 1FlintMI48502USA

Background:Children from underrepresented populations exhibit low levels of physical activity(PA),diet quality,and health-related quality of life(QoL),but participation in extracurricular activities may positively impact these health ***:To examine differences in PA,dietary behavior,and QoL in underrepresented children by extracurricular activity dose(0,1,≥2)and type(sports,dance/martial arts,art/music).methods:Children(N=754;Grades 4–6)completed the Physical Activity Questionnaire for Children,KidsScreen-27(QoL),and the School Physical Activity and Nutrition Survey and self-reported extracurricular activity ***-way mANOVA tests were used in this ***:Individuals participating in 1 and≥2 activities(pmartial arts(pmusic(p=0.029)had higher PA than *** participating in≥2 activities reported higher fruit intake compared to 1 activity and non-participants(p=0.009;pmpared to non-participants(p=0.001;p=0.025,respectively).Conclusions:Extracurricular activity participation was positively associated with health behaviors in underrepresented *** may be encouraged to allocate some of their resources to extracurricular activity programing.

关键词： Physical activity Dietary behavior Quality of life Youth Sport participation

Accelerated partial breast irradiation: Past, present, and future

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World Journal of Clinical Oncology 2016年第5期7卷 370-379页

作者： Anne W Tann sandra S Hatch melissa m Joyner Lee R Wiederhold Todd A Swanson Department of Radiation Oncology the University of Texas Medical Branch

Accelerated partial breast irradiation(APBI) focuses higher doses of radiation during a shorter interval to the lumpectomy cavity, in the setting of breast conserving therapy for early stage breast cancer. The utilization of APBI has increased in the past decade because of the shorter treatment schedule and a growing body of outcome data showing positive cosmetic outcomes and high local control rates in selected patients undergoing breast conserving therapy. Technological advances in various APBI modalities, including intracavitary and interstitial brachytherapy, intraoperative radiation therapy, and external beam radiation therapy, have made APBI more accessible in the community. Results of early APBI trials served as the basis for the current consensus guidelines, and multiple prospective randomized clinical trials are currently ongoing. The pending long term results of these trials will help us identify optimal candidates that can benefit from ABPI. Here we provide an overview of the clinical and cosmetic outcomes of various APBI techniques and review the current guidelines for selecting suitable breast cancer patients. We also discuss the impact of APBI on the economics of cancer care and patient reported quality of life.

关键词： Breast cancer Intracavitary brachytherapy Accelerated partial breast irradiation Interstitial brachytherapy