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Perception of artificial conspecifics by bearded dragons(Pogona vitticeps)

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Integrative Zoology 2019年第2期14卷 214-222页

作者： Anna FROHNWIESER thomas W.PIKE John c.MURRAY Anna WILKINSON School of Life Sciences University of LincolnLincolnUK School of computer Science University of LincolnLincolnUK Wildlife Research center Kyoto UniversityKyotoJapan

Artificial animals are increasingly used as conspecific stimuli in animal behavior ***,researchers often have an incomplete understanding of how the species under study perceives conspecifics,and,hence,which features are needed for a stimulus to be perceived *** investigate the features that bearded dragons(Pogona vitticeps)attend to,we measured their lateralized eye use when assessing a successive range of *** ranged through several stages of realism in artificial conspecifics,to see how features such as color,the presence of eyes,body shape and motion influence *** found differences in lateralized eye use depending on the sex of the observing bearded dragon and the artificial conspecific,as well as the artificial conspecific’s ***,this approach can inform the design of robotic animals that elicit biologically-meaningful responses in live animals.

关键词： bearded dragons conspecifics lateralized eye use perception

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HPLc-UV法测定银杏内酯A、B、c

天津中医药 2024年第9期41卷 1182-1186页

作者：胡哲铭皮紫月 JOHN OSILAMA thomas 郭盼天津中医药大学现代中药发现与制剂技术教育部工程中心天津301617

[目的]建立高效液相色谱-紫外检测器(HPLc-UV)法测定银杏内酯A、B、c的浓度,并对其进行方法学验证。[方法]考察了包括检测波长、8种不同的流动相体系及其比例、进样量、流速和柱温。方法验证涵盖了专属性、精密度、准确度、线性范围、... 详细信息

[目的]建立高效液相色谱-紫外检测器(HPLc-UV)法测定银杏内酯A、B、c的浓度,并对其进行方法学验证。[方法]考察了包括检测波长、8种不同的流动相体系及其比例、进样量、流速和柱温。方法验证涵盖了专属性、精密度、准确度、线性范围、重复性、系统适用性、加样回收率和稳定性。[结果]色谱柱为Agilent Tc-5 c_(18),检测波长为220 nm,流动相为水-甲醇(70∶30),进样量为20μL,柱温30℃,流速为1.0 mL/min且线性关系良好,色谱峰之间无互相干扰。[结论]该方法准确、有效,经济且易得,操作简单,为其他银杏内酯药物含量测定提供了可靠的参考。

关键词：银杏内酯高效液相色谱方法学验证

Estimation of diaphragm wall deflections for deep braced excavation in anisotropic clays using ensemble learning

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Geoscience Frontiers 2021年第1期12卷 365-373页

作者： Runhong Zhang chongzhi Wu Anthony T.c.Goh thomas Bohlke Wengang Zhang School of civil Engineering Chongqing UniversityChongqing400045China School of civil and Environmental Engineering Nanyang Technological University639798Singapore Institute of Engineering Mechanics Karlsruhe Institute of Technology(KIT)Kaiserstraße 1076131KarlsruheGermany Key Laboratory of New Technology for construction of cities in Mountain Area Chongqing UniversityMinistry of EducationChongqing400045China

This paper adopts the NGI-ADP soil model to carry out finite element analysis,based on which the effects of soft clay anisotropy on the diaphragm wall deflections in the braced excavation were *** than one thousand finite element cases were numerically analyzed,followed by extensive parametric *** models were developed via ensemble learning methods(ELMs),including the e Xtreme Gradient Boosting(XGBoost),and Random Forest Regression(RFR)to predict the maximum lateral wall deformation(δhmax).Then the results of ELMs were compared with conventional soft computing methods such as Decision Tree Regression(DTR),Multilayer Perceptron Regression(MLPR),and Multivariate Adaptive Regression Splines(MARS).This study presents a cutting-edge application of ensemble learning in geotechnical engineering and a reasonable methodology that allows engineers to determine the wall deflection in a fast,alternative way.

关键词： Anisotropic clay NGI-ADP Wall deflection Ensemble learning eXtreme gradient boosting Random forest regression

Scattering Behavior of Waveguide channels of a New coupled Integrable Dispersionless System

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chinese Physics Letters 2011年第12期28卷 43-46页

作者： Abbagari Souleymanou Victor K.Kuetche thomas B.Bouetou Timoleon c.Kofane National Advanced School of Engineering University of Yaounde IP.O.Box 8390Cameroon Department of Physics Faculty of ScienceUniversity of Yaounde IP.O.Box 812Cameroon Department of Mathematics Faculty of ScienceUniversity of Yaounde IP.O.Box 812Cameroon

Based upon the powerful Hirota method for unearthing soliton solutions to nonlinear partial differential evolution equations,we investigate the scattering properties of a new coupled integrable dispersionless system while surveying the interactions between its self-confined travelling wave *** a result,we ascertain three types of scattering features depending strongly upon a characteristic *** such findings to depict soliton solutions with nonzero angular momenta,we derive an extended form of the dispersionless system,which is valuable for further physical applications.

关键词： parameter soliton dispersion

Reforestation Programs in Southwest china:Reported Success,Observed Failure, and the Reasons Why

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Journal of Mountain Science 2007年第4期4卷 275-292页

作者： christine Jane Trac Stevan Harrell thomas M. Hinckley Amanda c. Henck Department of Biology University of Washington Department of Anthropology Box 353010 University of Washington Seattle WA 98195 USA college of Forest Resources University of Washington Department of Earth and Space Sciences University of Washington

Ever since the disastrous floods of 1998, the chinese government has used the Natural Forest Protection and Sloping Land conversion Programs to promote afforestation and reforestation as means to reduce runoff, control erosion, and stabilize local livelihoods. These two ambitious programs have been reported as large-scale successes, contributing to an overall increase in china’s forest cover and to the stated goals of environmental stabilization. A small-scale field study at the project level of the implementation of these two programs in Baiwu Township, Yanyuan county, Sichuan, casts doubt upon the accuracy and reliability of these claims of success; ground observations revealed utter failure in some sites and only marginal success in others. Reasons for this discrepancy are posited as involving ecological, economic, and bureaucratic factors. Further research is suggested to determine whether these discrepancies are merely local aberrations or represent larger-scale failures in reforestation programs.

关键词： Forests afforestation reforestation grain-to-green natural forest protection plan china Sichuan Liangshan

Influence of La3+ ion in the yttria matrix in improving the microhardness of infrared transparent nano LaxY2-xO3 sintered via hybrid heating

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Journal of Advanced ceramics 2017年第3期6卷 240-250页

作者： Jijimon K. thomas Mathew c. T. Jacob KOSHY Sam SOLOMON Electronic Materials Research Laboratory Department of Physics Mar Ivanios College Thiruvananthapuram 695015 Kerala India

In the present work, hybrid sintering technique which couples the resistive heating and microwave heating is employed to sinter infrared transparent La0.15Y1.85O3 to 99.2% of the theoretical density for the first time to the best of our knowledge. The presence of La3+ in the yttria matrix improves the hardness properties to a greater extent without affecting the transmittance properties, but there is a deterioration in the thermal properties of the sample. So we have limited our studies to La0.15Y1.85O3 which shows better optical, thermal, and hardness properties. The pellets fabricated from the ultra-fine nano powder with average particle size of ~12 nm synthesized by combustion technique and sintered at 1430 ℃ with an average grain size of 0.22 μm show ~80.1% transmittance in the UV–visible region and 81% in mid infrared region. For a comparative study of the optical, mechanical, and thermal properties, two other variants of sintering strategies namely conventional sintering and microwave sintering are also employed. A comprehensive analysis on the hardness reveals that the hardness of the pellets sintered via hybrid heating is 9.73 GPa and is superior to the pellets sintered using the other two techniques. The thermal conductivity of the sample is also analyzed in detail. The results clearly indicate that the La0.15Y1.85O3 ultra-fine nano powder synthesised by the single-step combustion method and sintered via microwave hybrid heating shows better transmittance properties without compromising the mechanical properties, and can be used very effectively for the fabrication of infrared transparent windows and domes.

关键词： La3+ concentration microhardness hybrid sintering infrared transparent ceramics thermal conductivity

current role of palliative interventions in advanced pancreatic cancer

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World Journal of Gastrointestinal Surgery 2018年第7期10卷 75-83页

作者： chelsey c ciambella Rachel E Beard thomas J Miner Department of Surgical Oncology Warren Alpert Medical School Brown University

Pancreatic adenocarcinoma is the third leading cause of cancer death in the United States. Unfortunately, at diagnosis, most patients are not candidates for curative resection. Surgical palliation, a procedure performed with the intention of relieving symptoms or improving quality of life, comes to the forefront of management. This article reviews the palliative management of unresectable pancreatic cancer, including obstructive jaundice, duodenal obstruction and pain control with celiac plexus block. Although surgical bypasses for both biliary and duodenal obstructions usually achieve good technical success, they result in considerable perioperative morbidity and mortality, even when performed laparoscopically. The effectiveness of selfexpanding metal stents for biliary drainage is excellent with low morbidity. Surgical gastrojejunostomy for duodenal obstruction appears to be best for patients with a life expectancy of greater than 2 mo while endoscopic stenting has been shown to be feasible with good symptom relief in those with a shorter life expectancy. Regardless of the palliative procedure performed, all physicians involved must be adequately trained in end of life management to ensure the best possible care for patients.

关键词： Surgical palliation Duodenal obstruction Hepatojejunostomy Gastrojejunostomy Endoscopic stenting Malignant ascites celiac block Palliative triangle Pancreatic cancer Obstructive jaundice

Reduced non-cpG methylation is a potential epigenetic target after spinal cord injury

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Neural Regeneration Research 2023年第11期18卷 2489-2496页

作者： Zhourui Wu chen Li Ran Zhu Yiqiu cao thomas c.chen Liming cheng Key Laboratory of Spine and Spinal cord Injury Repair and Regeneration(Tongji University) Ministry of EducationShanghaiChina Division of Spine Department of OrthopedicsTongji HospitalTongji University School of MedicineShanghaiChina Institute of Spinal and Spinal cord Injury Tongji University School of MedicineShanghaiChina Department of Neurosurgery Keck School of MedicalUniversity of Southern CaliforniaLos AngelesCAUSA

DNA methylation is a critical epigenetic regulator in the occurrence and development of diseases and is closely related to various functional responses in relation to spinal cord *** investigate the role of DNA methylation in spinal cord injury,we constructed a library with reduced-representation bisulfite sequencing data obtained at various time points(day 0-42)after spinal cord injury in *** DNA methylation levels,specifically non-cpG(cHG and cHH)methylation levels,decreased modestly following spinal cord *** post-spinal cord injury were classified as early(day 0-3),intermediate(day7-14),and late(day 28-42)based on similarity and hie rarchical cluste ring of global DNA methylation *** non-cpG methylation level,which included cHG and cHH methylation levels,was markedly reduced despite accounting for a minor proportion of total methylation *** multiple genomic sites,including the 5’untranslated regions,promoter,exon,intron,and 3’untranslated regions,the non-cpG methylation level was markedly decreased following spinal cord injury,whereas the cpG methylation level remained unchanged at these *** one-half of the differentially methylated regions were located in intergenic areas;the other differentially methylated regions in both cpG and non-cpG regions were cluste red in intron regions,where the DNA methylation level was *** function of genes associated with differentially methylated regions in promoter regions was also *** Gene Ontology analysis results,DNA methylation was implicated in a number of essential functional responses to spinal cord injury,including neuronal synaptic connection creation and axon ***,neither cpG methylation nor non-cpG methylation was implicated in the functional response of glial or inflammatory *** summary,our work elucidated the dynamic pattern of DNA methylation in the spinal co rd following injury and identified reduced noncpG meth

关键词： cpG methylation cytosine fraction differentially methylated regions DNA methylation DNA methyltransferases dynamic signatures Gene Ontology non-cpG methylation single-cell RNA-Seq spinal cord injury

Investigations of ZnO thin films deposited by a reactive pulsed laser ablation

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Science china(Technological Sciences) 2009年第1期52卷 99-103页

作者： Y. c. SOO H. KANDEL M. A. thomas c. P. DAGHLIAN Department of Physics and Astronomy University of Arkansas at Little Rock Little Rock E. M. Facilities Dartmouth College Hanover

Highly transparent ZnO thin films were deposited at different substrate temperatures by pulsed laser deposition in an oxygen atmosphere. The thin films were characterized by various techniques including X-ray diffraction, scanning electron microscopy, optical absorption, and photoluminescence. We demonstrated that oriented wurtzite ZnO thin films could be deposited at room temperature using a high purity zinc target. Variable temperature photoluminescence revealed new characteristics in the band edge emission. The underlying mechanism for the observed phenomena was also discussed.

关键词： thin films pulsed laser deposition optical property zinc oxide