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Between Eurasia and China: Saddles Excavated in Xinjiang at Zaghunluq and Subeshi

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欧亚学刊

欧亚学刊 2011年 59-75页

作者： Katheryn m.Linduff sandra Olsen

Introduction sometime between six and four thousand years ago,human beings discovered that by riding on horseback they could travel at greater speeds and for longer distances than they could on *** discovery transformed the course of human history,enabling more efficient exploration and incursions into remote *** such transport,and the ability to move goods,weapons and food,conquerors such as Alexander the Great(356-323 BCE)could

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Detection and determination of undeclared synthetic caffeine in weight loss formulations using HPLC-DAD and UHPLC-mS/mS

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Journal of Pharmaceutical Analysis 2018年第6期8卷 366-372页

作者： Carine Viana Gabriela m.Zemolin Thaís R.Dal molin Luciana Gobo sandra maria Ribeiro Gabriela C.Leal Gabriela Z.marcon Leandro m.de Carvalho Graduate Program in Pharmaceutical Sciences Federal University of Santa Maria (UFSM) Center of Health Sciences Federal University of Santa Maria (UFSM) Department of Chemistry Federal University of Santa Maria (UFSM)

Caffeine is present in products marketed for weight loss, with the purpose of increasing thermogenesis and lipid metabolism. The dosage declared by the product manufacturer, or even its presence, is not always correctly described on the label. This work aimed to investigate the undeclared synthetic caffeine in weight loss formulations by a high-performance liquid chromatography with diode array detection(HPLC-DAD) method. From one hundred products purchased through Brazilian e-commerce, seventeen contained caffeine, either naturally or synthetically added to formulation. The caffeine-containing samples were confirmed by an ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-mS/mS) method, and adulteration was clearly proven in five products. The content highest caffeine contained 448.8 mg per dose. Other irregularities were also found; nevertheless, the most serious was the addition of synthetic drugs without asking the consumers. Additional drugs expose the consumer to more possible side-effects as well as deleterious drug interactions. Intentional adulteration with any unlabeled substance is typically motivated by a desire to increase or alter the claimed effect of the marketed product to gain a commercial advantage.

关键词： Undeclared synthetic caffeine Weight loss formulations HPLC-DAD UHPLC-mS/mS

Preparation and characterization of phosphate-modified mesoporous TiO2 incorporated in a silica matrix and their photocatalytic properties in the photodegradation of Congo red

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Frontiers of materials Science 2017年第3期11卷 250-261页

作者： Alberto ESTRELLA GONZALEZ maximiliano ASOmOZA Ulises ARELLANO sandra CIPAGAUTA DiAZ Silvia SOLíS Department of Chemistry Metropolitan Autonomous University-lztapalapa P.O. Box 55-532 C.P. 09340 México City México

This study describes the development of mesostructured TiO2 photo- catalysts modified with PO4^3- to improve its specific surface area and reduce the recombination rate of the electron-hole pairs. The mesoporous photocatalyst was successfully incorporated into a high specific surface area silica matrix by the hydrolysis reaction of tetraethyl orthosilicate （TEOS）. Pluronic 123 and phosphoric acid were used as the directing agent for the structure of the mesoporous TiO2 and as a source of phosphorus, respectively, TiO2, P/TiO2, TiO2-SiO2 and P/TiO2-SiO2 materials were characterized by BET, XRD, TEm-EDS, FTIR and UV-vis DRS measurements. The photoactivity of TiO2-SiO2 nanocomposites containing 15 wt.% photocatalystJsilica was evaluated in the degradation reaction of anionic dyes with UV radiation. The proposed nanomaterials showed high potential for applications in the remediation of wastewater, being able to reuse in several cycles of reaction, maintaining its photoactivity and stability. The separation and recovery time of the material is reduced between cycles since no centrifugation or filtration processes are required after the photooxidation reaction.

关键词： photocatalysis phosphated TiO2 TiO2-SiO2 Congo red dye

Tree mortality and biomass loss in drought-aff ected forests of East Texas,USA

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Journal of Forestry Research 2021年第1期32卷 67-80页

作者： mukti Ram Subedi Weimin Xi Christopher B.Edgar sandra Rideout-Hanzak ming Yan Department of Biological and Health Sciences Texas A&M University-KingsvilleKingsvilleTX 78363USA Department of Forest Resources University of MinnesotaSt.PaulMN 55108USA Department of Rangeland and Wildlife Sciences and Caesar Kleberg Wildlife Research Institute Texas A&M University-KingsvilleKingsvilleTX 78363USA School of Life Sciences Shanxi Normal UniversityLinfen 041004People’s Republic of China

Changes in tree mortality due to severe drought can alter forest structure,composition,dynamics,ecosystem services,carbon fl uxes,and energy interactions between the atmosphere and land *** utilized long-term(2000‒2017,3 full inventory cycles)Forest Inventory and Analysis(FIA)data to examine tree mortality and biomass loss in drought-aff ected forests for East Texas,*** that experienced six or more years of droughts during those censuses were selected based on 12-month moderate drought severity[Standardized Precipitation Evaporation Index(SPEI)-1.0].Plots that experienced other disturbances and inconsistent records were excluded from the *** total,222 plots were retained from nearly 4000 *** nonlinear mixed models(GNmms)were used to examine the changes in tree mortality and recruitment rates for selected *** results showed that tree mortality rates and biomass loss to mortality increased overall,and across tree sizes,dominant genera,height classes,and *** average mortality rate of 5.89%year−1 during the study period could be incited by water stress created by the regional prolonged and episodic drought *** overall plot and species-group level recruitment rates decreased during the study *** mortality showed mixed results regarding basal area and forest density using all plots together and when analyzed the plots by stand origin and *** mortality rates of smaller trees were detected and were likely compounded by densitydependent *** analysis of drought-induced tree mortality using hydro-meteorological data along with drought severity and length gradient is suggested to better understand the eff ects of drought on tree mortality and biomass loss around and beyond East Texas in the southeastern United States.

关键词： Generalized nonlinear mixed model Endogenous factors Drought index Standardized precipitation evaporation index(SPEI) Above-ground biomass Competition index Biomass lost to mortality East Texas

Quantifying the spatial and temporal distribution of tanglehead (Heteropogon contortus) on South Texas rangelands

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Ecological Processes 2018年第1期7卷 14-22页

作者： Jose m.mata Humberto L.Perotto-Baldivieso Fidel Hernández Eric D.Grahmann sandra Rideout-Hanzak John T.Edwards michael T.Page Taylor m.Shedd Caesar Kleberg Wildlife Research Institute Texas A&M University-Kingsville700 University Blvd.MSC 218KingsvilleTX 78363USA

Introduction:Tanglehead is a grass native to southwestern US rangelands;however,its prevalence as a native invasive on South Texas rangelands has increased rapidly during the last *** areas of monotypic stands have emerged in Jim Hogg,Duval,Brooks,and Kleberg *** aim of this research is to understand the spatial and temporal dynamics of these invasions as a model for the assessment of native invasive *** specific objectives were to(1)evaluate the feasibility of classifying tanglehead using 1-m resolution imagery data,(2)assess the spatial and temporal distribution of tanglehead in relation to soil type and distance from roads,and(3)quantify the temporal and spatial distribution of tanglehead on our study *** combined remote sensing approaches with landscape metrics to quantify the spatial and temporal distribution of tanglehead in five locations across our study *** calculated the normalized difference vegetation index and combined it with the original aerial imagery to conduct an unsupervised classification with the following land cover classes:woody vegetation,tanglehead,non-tanglehead herbaceous,and bare *** type and the distance from roads were assessed to determine the relationship between these factors and tanglehead spatial ***:We were able to successfully map tanglehead using the 1-m *** image classification approach resulted in accuracies greater than 85%for all *** occurred in sandy,loamy sand,and sandy loam *** 70% of tanglehead cover occurred within the first 150 m from the edge of *** cover increased from 7.1%(SE=1.1%)in 2008 to 17.8%(SE=5.4%)in *** established,small patches of tanglehead began aggregating or coalescing with existing stands,thereby creating larger patches over larger ***:Our study has shown the value of analyzing spatiotemporal dynamics of tanglehead with remote sensing techniques and landscape metrics to improve our unders

关键词： distribution landscape sandy

Bile leakage after loop closure vs clip closure of the cystic duct during laparoscopic cholecystectomy:A retrospective analysis of a prospective cohort

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World Journal of Gastrointestinal Surgery 2020年第1期12卷 9-16页

作者： sandra C Donkervoort Lea m Dijksman Aafke H van Dijk Emile A Clous marja A Boermeester Bert van Ramshorst Djamila Boerma Department of Surgery Onze Lieve Vrouwe GasthuisAmsterdam 1090 HMNetherlands Department of Research and Epidemiology St.Antonius HospitalNieuwegein 3435 CMNetherlands Department of Surgery Academic Medical CentreAmsterdam 1105 AZNetherlands

BACKGROUND Laparoscopic cholecystectomy(LC)is one of the most frequently performed surgical *** stump leakage is an underestimated,potentially life threatening complication that occurs in 1%-6%of the *** a secure cystic duct occlusion technique during LC,bile leakage becomes a preventable *** To investigate the effect of polydioxanone(PDS)loop closure of the cystic duct on bile leakage rate in LC *** In this retrospective analysis of a prospective cohort,the effect of PDS loop closure of the cystic duct on bile leakage complication was compared to patients with conventional clip *** regression analysis was used to develop a risk score to identify bile leakage *** rate was assessed for categories of patients with increasing levels of bile leakage *** Of the 4359 patients who underwent LC,136(3%)underwent cystic duct closure by a PDS ***,loop closure patients had significantly more complicated biliary disease compared to the clipped closure *** the loop closure cohort,zero(0%)bile leakage occurred compared to 59 of 4223(1.4%)clip closure *** patients at increased bile leakage risk(risk score≥1)rates were 1.6%and up to 13%(4/30)for clip closure patients with a risk score≥*** risk increase paralleled a stepwise increase of actual bile leakage complication for clip closure patients,which was not observed for loop closure *** Cystic duct closure with a PDS loop during LC may reduce bile leakage in patients at increased risk for bile leakage.

关键词： Laparoscopic cholecystectomy Cystic duct occlusion Bile leak Endo-loop

The role of recrystallization and grain growth in optimizing the sheet texture of magnesium alloys with calcium addition during annealing

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Journal of magnesium and Alloys 2020年第1期8卷 252-268页

作者： Fei Guo Risheng Pei Luyao Jiang Dingfei Zhang sandra Korte-Kerzel Talal Al-Samman College of materials Science and Engineering Chongqing University of Technology400054 ChongqingChina Chongqing Key Laboratory of mold Technology Chongqing University of Technology400054 ChongqingChina Institut für metallkunde und metallphysik RWTH Aachen University52056 AachenGermany College of materials Science and Engineering Chongqing University400044 ChongqingChina

The contribution of recrystallization and grain growth to the texture evolution in AZ31 alloy and a modified version AZ31+0.5 wt.%Ca was investigated utilizing a multi-step annealing *** results showed that the addition of Ca triggered a considerable texture modification by increasing the texture spread and decreasing the overall texture *** effect was found to be temperature *** the annealing temperature remained lower than 450℃,a weak double peak texture with large basal pole tilt towards the RD was *** is correlated to microstructure observations of a large number of Ca-containing nano-sized particles that seemed to suppress grain growth below 450℃,which stabilized the weak recrystallization *** favorable texture was lost upon annealing at higher *** AZ31,recrystallization nuclei were found to preserve the orientation of their deformed parents,which offered limited potential to optimize the texture via annealing *** growth of recrystallized grains resulted in a distinct sheet texture transition from a double-peak to a single-peak basal *** of grain boundary energy and grain topology are discussed to explain the growth advantage of the sharp basal component over other orientations.

关键词： magnesium alloys microstructure Texture Recrystallization Grain growth

Nurses' views of fundamental relational skills used in clinical practice: a cross-sectional pilot study

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Frontiers of Nursing 2021年第3期8卷 223-232页

作者： Fiona Timmins Jan m.A.de Vries Yvonne muldowney Catherine mc Cabe Jacqueline Whelan Sinead Buckley sandra mcCarthy The School of Nursing and midwifery Trinity CollegeDublin 2Ireland Portlaoise General Hospital BallyroanPortlaoiseCo.LaoisIreland

Objective:Effective communication skills are one of the core competencies of nursing curricula *** are generally regarded as *** our complete trust in the profession,deficiencies and gaps ***,it is not clear to which extent nurses use key communication skills in practice,and whether or not confident in using these skills compounds environmental issues that *** study explored nurse’s confidence and application of relational skills competencies in nursing ***:A 13-item online survey was used to collect ***:Being self-aware on key areas where there was more *** also lacked confidence in exploring the impact of their personal feelings and values on their *** were also less confident on responding appropriately to instances of unsafe or unprofessional practice and using information and communication systems and ***:Given the potential impact of poor relational skills on quality client care,an increased emphasis on caring and compassion,and the ever-expanding use of communication technologies,there is a need to explore the need for reflective practice to enhance continuous professional development for nurses to enhance their relational skills.

关键词： communication relational nurse caring nursing competencies technology listening

The effect of particle size and amount of inoculum on fungal treatment of wheat straw and wood chips

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Journal of Animal Science and Biotechnology 2017年第1期8卷 217-225页

作者： sandra J. A. van Kuijk Anton S. m. Sonnenberg Johan J. P. Baars Wouter H. Hendriks John W. Cone Animal Nutrition Group Wageningen University De Elst 1 6708WD Wageningen The Netherlands Plant Breeding Wageningen University Droevendaalsesteeg 1 6708PB Wageningen The Netherlands

Background： The aim of this study was to optimize the fungal treatment of lignocellulosic biomass by stimulating the colonization. Wheat straw and wood chips were treated with Ceriporiopsis subvermispora and Lentinula edodes with various amounts of colonized millet grains（0.5, 1.5 or 3.0 % per g of wet weight of substrate） added to the substrates. Also, wheat straw and wood chips were chopped to either 0.5 or 2 *** of the fungal treatment after 0, 2, 4, 6, or 8 wk of incubation was determined by changes in chemical composition, in vitro gas production（IVGP） as a measure for rumen degradability, and ergosterol content as a measure of fungal ***： Incomplete colonization was observed for C. subvermispora treated wheat straw and L. edodes treated wood chips. The different particle sizes and amounts of inoculum tested, had no significant effects on the chemical composition and the IVGP of C. subvermispora treated wood chips. Particle size did influence *** treatment of wheat straw. The L. edodes treatment of 2 cm wheat straw resulted in a more selective delignification and a higher IVGP than the smaller particles. Addition of 1.5 % or 3 % L. edodes inoculum to wheat straw resulted in more selective delignification and a higher IVGP than addition of 0.5 % ***： Particle size and amount of inoculum did not have an effect on C. subvermispora treatment of wood chips. At least 1.5 % L. edodes colonized millet grains should be added to 2 cm wheat straw to result in an increased IVGP and acid detergent lignin（ADL） degradation.

关键词： Amount of inoculum Fungal treatment In vitro rumen degradability Lignin degradation Lignocellulosic biomass Particle size