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Bayesian data analysis to quantify the uncertainty of intact rock strength

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Journal of Rock mechanics and Geotechnical Engineering 2018年第1期10卷 11-31页

作者： luis Fernando Contreras Edwin T.Brown marc Ruest The University of Queensland St Lucia CampusBrisbaneQLD 4072Australia Golder Associates Pty.Ltd. BrisbaneAustralia

One of the main difficulties in the geotechnical design process lies in dealing with uncertainty. Uncertainty is associated with natural variation of properties, and the imprecision and unpredictability caused by insufficient information on parameters or models. Probabilistic methods are normally used to quantify uncertainty. However, the frequentist approach commonly used for this purpose has some ***, it lacks a formal framework for incorporating knowledge not represented by data. Second, it has limitations in providing a proper measure of the confidence of parameters inferred from data. The Bayesian approach offers a better framework for treating uncertainty in geotechnical design. The advantages of the Bayesian approach for uncertainty quantification are highlighted in this paper with the Bayesian regression analysis of laboratory test data to infer the intact rock strength parameters σand mused in the Hoek-Brown strength criterion. Two case examples are used to illustrate different aspects of the Bayesian methodology and to contrast the approach with a frequentist approach represented by the nonlinear least squares(NLLS) method. The paper discusses the use of a Student’s t-distribution versus a normal distribution to handle outliers, the consideration of absolute versus relative residuals, and the comparison of quality of fitting results based on standard errors and Bayes factors. Uncertainty quantification with confidence and prediction intervals of the frequentist approach is compared with that based on scatter plots and bands of fitted envelopes of the Bayesian approach. Finally, the Bayesian method is extended to consider two improvements of the fitting analysis. The first is the case in which the Hoek-Brown parameter, a, is treated as a variable to improve the fitting in the triaxial region. The second is the incorporation of the uncertainty in the estimation of the direct tensile strength from Brazilian test results within the overall evaluati

关键词： Uncertainty Intact rock strength Bayesian analysis Hoek-Brown criterion

CHARACTERIZATIONS OF SEmI-PREQUASI-INVEXITY

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Journal of Systems Science & Complexity 2014年第5期27卷 1008-1026页

作者： ZHAO Yingxue mENG Xiaoge QIAO Han WANG Shouyang COLADAS URIA luis School of International Trade and Economics University of International Business and Economics School of Economics and management Beijing University of Aeronautics and Astronautics School of management University of Chinese Academy of Sciences Institute of Systems Science Academy of Mathematics and Systems ScienceChinese Academy of Sciences Department of Statistics and Operations Research Faculty of MathematicsSantiago de Compostela University

Because of its importance in optimization theory,the concept of convexity has been generalized in various *** these generalizations,to seek some practical criteria for them is especially *** this paper,some criteria are developed for semi-prequasi-invexity,which includes prequasi-invexity as the special *** characterizations among semi-prequasi-invex functions,strictly semi-prequasi-invex functions,and strongly semi-prequasi-invex functions are presented.

关键词： Convex programming dense semi-prequasi-invex function strictly semi-prequasi-invex function strongly semi-prequasi-invex function

Evaluating soil erosion and runoff dynamics in a humid subtropic, low stream order, southern plains watershed from cultivation and solar farm development

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International Soil and Water Conservation Research 2024年第2期12卷 432-445页

作者： luis mier-Valderrama Julianna Leal Humberto L.Perotto-Baldivieso Brent Hedquist Hector m.menendez Ambrose Anoruo Benjamin L.Turner Department of Agriculture Agribusinessand Environmental ScienceTexas A&M University-KingsvilleKingsvilleTXUSA Department of Rangeland and Wildlife Sciences And Caesar Kleberg Wildlife Research InstituteTexas A&M University-KingsvilleKingsvilleTXUSA Department of Physics and Geosciences Texas A&M University-KingsvilleKingsvilleTXUSA South Dakota State University West River Ag CenterRapid CitySDUSA

much work has been done to understand and improve soil and water conservation where agriculture has driven land use *** is known about soil-and water-related impacts from intensification driven by solar farming,especially at *** we employed Hydrologic Engineering Center's Hydrologic modeling System(HEC-HmS)to model Pond Creek,a rural watershed in Texas,*** use is primarily crop cultivation and secondarily pasture for cattle ***,several industrial-scale projects are planned to convert≈15–30%of Pond Creek from agriculture to solar *** model was parameterized using public data sources and information from local stakeholders,then calibrated to several historical precipitation *** were conducted by varying precipitation depth,duration,and land uses:native vegetation pre-cultivation(control),cultivation(current),current conditions with 15%solar farm conversion(solar),and current conditions with 30%solar farm conversion(solar x2).Shifting to solar farming led to significant increases in cumulative sediment load(+12%–30%),with no significant differences in peak discharge rate changes(+0.38%–4%).Comparison to soil loss tolerance values showed current and solar treatment erosion rates exceeded tolerance values between 0.17 and 2.29 tons per hectare and all treatments were significantly different than the native *** discuss high leverage strategies applicable to solar farm development sites as well as watersheds where they *** demand for land for renewable energy such as solar farming warrants greater attention from the soil and water conservation community to anticipate and mitigate impacts across landscapes.

关键词： Erosion Sediment loading Runoff Watershed management Solar energy HEC-HmS

A decrease of docosahexaenoic acid in testes of mice fed a high-fat diet is associated with impaired sperm acrosome reaction and fertility

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Asian Journal of Andrology 2021年第3期23卷 306-313页

作者： Julio Bunay Luz-maria Gallardo Jorge luis Torres-Fuentes m Veronica Aguirre-Arias Renan Orellana Nestor Sepulveda Ricardo D moreno Physiology Department Faculty of Biological SciencesPontificia Universidad Cat6lica de Chile(PUC)Santiago 8331150Chile Department of Chemistry and Biological Sciences Health Sciences FacultyUniversidad Bernardo 0 HigginsSantiago 8370854Chile Center of Excellence in Biotechnology of Reproduction Universidad de la FronteraTemuco 4780000Chile.

Obesity is a major worldwide health problem that is related to most chronic diseases,including male *** to its wide impact on health,mechanisms underlying obesity-related infertility remain *** this study,we report that mice fed a high-fat diet(HFD)for over 2 months showed reduced fertility rates and increased germ cell apoptosis,seminiferous tubule degeneration,and decreased intratesticular estradiol(E2)and E2-to-testosterone ***,we also detected a decrease in testicular fatty acid levels,behenic acid(C22:0),and docosahexaenoic acid(DHA,22:6n-3),which may be related to the production of dysfunctional ***,we did not detect any changes in the frequency of seminiferous tubule stages,sperm count,or rate of in vitro ***,there was an increase in spontaneous and progesterone-induced acrosomal exocytosis(acrosome reaction)in spermatozoa from HFD-fed *** data suggest that a decrease in E2 and fatty acid levels influences spermatogenesis and some steps of acrosome biogenesis that will have consequences for ***,our results add new evidence about the adverse effect of obesity in male reproduction and suggest that the acrosomal reaction can also be affected under this condition.

关键词： cholesterol estradiol fat acid testis testosterone

Juxta-caval hepatic angiomyolipoma masquerading as hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2003年第4期2卷 617-621页

作者： Alan m Hawxby michael Torbenson Elliot Fishman Leo Lawler luis m Arrazola Andrew S Klein the Departments of Surgery The Johns Hopkins Hospital Baltimore MD 21287 USA Pathology The Johns Hopkins Hospital Baltimore MD 21287 USA Radiology The Johns Hopkins Hospital Baltimore MD 21287 USA the Departments of Surgery The Johns Hopkins Hospital Baltimore MD 21287 USA

Hepatic angiomyolipoma is an uncommon primary benign epithelial liver neoplasm. most patients with angiomyolipomas are middle-aged women who commonly present with epigastric fullness or pain. Angiomyolipomas are tumors consisting of three tissue types: blood vessels, smooth muscle, and fat. Hepatic angiomyolipomas may be difficult to differentiate from other liver neoplasms by noninvasive imaging. We report a 58-year-old asymptomatic woman with a mass in the right lobe of the liver, found incidentally on routine abdominal sonography. Preoperative radiographic evaluation revealed a 6.5-cm hypervascular lesion abutting the inferior vena cava. Preoperative histologic study demonstrated an epithelial neoplasm suspicious for hepatocellular carcinoma. metastatic workup was negative. At resection, the tumor was found to be an angiomyolipoma composed of lipoid, vascular and smooth muscle cells. Further staining was positive for HmB-45. Resection margins were negative. The woman had an uneventful recovery and was discharged on postoperative day seven. She currently remains well several months after her right hepatectomy.

关键词： angiomyolipoma hepatectomy radiographic evaluation multiplanar imaging

Abdominal compartment syndrome among surgical patients

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World Journal of Gastrointestinal Surgery 2021年第4期13卷 330-339页

作者： monica Leon luis Chavez Salim Surani Department of medicine Centro Medico ABCCiudad de Mexico 01120Mexico Department of medicine University of TexasEl PasoTX 79905United States Department of medicine Texas A&M UniversityCorpus ChristiTX 78405United States

Abdominal compartment syndrome(ACS)develops when organ failure arises secondary to an increase in intraabdominal *** abdominal pressure is determined by multiple factors such as blood pressure,abdominal compliance,and other factors that exert a constant pressure within the abdominal *** conditions in the critically ill may increase abdominal pressure compromising organ perfusion that may lead to renal and respiratory *** surgical and trauma patients,aggressive fluid resuscitation is the most commonly reported risk factor to develop *** conditions that have also been identified as risk factors are ascites,hemoperitoneum,bowel distention,and large *** patients with abdominal trauma possess a higher risk of developing intra-abdominal hypertension(IAH).Certain surgical interventions are reported to have a higher risk to develop IAH such as damage control surgery,abdominal aortic aneurysm repair,and liver transplantation among *** monitoring of organ function and intra-abdominal pressure(IAP)allows clinicians to diagnose ACS rapidly and intervene with target-specific management to reduce *** decompression followed by temporary abdominal closure should be considered in all patients with signs of organ *** is still a great need for more studies to determine the adequate timing for interventions to improve patient outcomes.

关键词： Intra-abdominal hypertension Abdominal compartment syndrome Intraabdominal pressure Open abdomen treatment multiple organ failure Surgical decompression

Improving outcomes in pancreatic cancer: Key points in perioperative management

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World Journal of Gastroenterology 2014年第39期20卷 14237-14245页

作者： José m álamo luis m marín Gonzalo Suarez Carmen Bernal Juan Serrano Lydia Barrera miguel A Gómez Jordi muntané Francisco J Padillo Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREH o Ciberehd) Instituto de Salud Carlos Ⅲ 28029 Madrid Spain Francisco J Padillo Department of General Surgery Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla 41013 Seville Spain

This review focused in the perioperative management of patients with pancreatic cancer in order to improve the outcome of the disease. We consider that the most controversial points in pancreatic cancer management are jaundice management, vascular resection and neo-adjuvant therapy. Preoperative biliary drainage is recommended only in patients with severe jaundice, as it can lead to infectious cholangitis, pancreatitis and delay in resection, which can lead to tumor progression. The development of a phase III clinical trial is mandatory to clarify the role of neo-adjuvant radiochemotherapy in pancreatic adenocarcinoma. Venous resection does not adversely affect postoperative mortality and morbidity, therefore, the need for venous resection should not be a contraindication to surgical resection in selected patients. The data on arterial resection alone, or combined with vascular resection at the time of pancreatectomy are more heterogeneous, thus, patient age and comorbidity should be evaluated before a decision on operability is made. In patients undergoing R0 resection, arterial resection can also be performed.

关键词： Pancreatic cancer Obstructive jaundice Preoperative drainage Neo-adjuvant therapy Vascular resection

Stimuli-responsive photoluminescent copper(Ⅰ) halides for scintillation, anticounterfeiting, and light-emitting diode applications

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Aggregate 2024年第5期5卷 465-480页

作者： Dilruba A.Popy Yashpal Singh Yauhen Tratsiak Abby m.Cardoza John m.Lane luis Stand mariya Zhuravleva Neeraj Rai Bayram Saparov Department of Chemistry and Biochemistry University of OklahomaNormanOklahomaUSA Dave C.Swalm School of Chemical Engineering and Center for Advanced Vehicular Systems Mississippi State UniversityMississippi StateMississippiUSA Scintillation materials Research Center University of TennesseeKnoxvilleTennesseeUSA

Highly sensitive stimuli-responsive luminescent materials are crucial for appli-cations in optical sensing,security,and ***,we report two zero-dimensional(0D)copper(I)halides,(TEP)_(2)Cu_(2)Br_(4),(TEP)_(2)Cu_(4)Br_(6),and 1D(TEP)_(3)Ag_(6)Br_(9),which are comprised of isolated[Cu_(2)Br_(4)]^(2-),[Cu_(4)Br_(6)]^(2-),and[Ag_(6)Br_(9)]3-polyanions,respectively,separated by TEP^(+)(tetraethylphosphonium[TEP])cations.(TEP)_(2)Cu_(2)Br_(4) and(TEP)_(2)Cu_(4)Br_(6) demonstrate greenish-white and orange-red emissions,respectively,with near unity photoluminescence quantum yields,while(TEP)_(3)Ag_(6)Br_(9) is a poor light *** spectroscopy mea-surements and density-functional theory calculations reveal that photoemissions of these compounds originate from self-trapped excitons due to the excited-state distor-tions in the copper(I)halide *** of Cu(I)halides are radioluminescence active at room temperature under both X-andγ-rays *** light yields up to 15,800 ph/meV under 662 keVγ-rays of ^(137)Cs suggesting their potential for scintillation ***,(TEP)_(2)Cu_(2)Br_(4) and(TEP)_(2)Cu_(4)Br_(6) are inter-convertible through chemical stimuli or reverse *** addition,both compounds demonstrate luminescence on-off switching upon thermal *** sensitivity of(TEP)_(2)Cu_(2)Br_(4) and(TEP)_(2)Cu_(4)Br_(6) to the chemical and thermal stimuli coupled with their ultrabright emission allows their consideration for applications such as solid-state lighting,sensing,information storage,and anticounterfeiting.

关键词： 0D copper(I)halides anticounterfeiting efﬁcient photoluminescence scintillators solid-state lighting

Endophytes versus biotrophic and necrotrophic pathogens—are fungal lifestyles evolutionarily stable traits?

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Fungal Diversity 2013年第3期60卷 125-135页

作者： luis Delaye Graciela García-Guzmán martin Heil Departamento de Ingeniería Genética Centro de Investigación y de Estudios Avanzados(CINVESTAV)IrapuatoGuanajuatoMexico Departamento de Ecología Evolutiva Instituto de EcologíaUNAMMéxico CityMexico

Endophytes infect living plant tissues without causing symptoms of ***,many of them contribute to the resistance phenotype of their ***,fungal endophytes are generally closely related to plant pathogens,fungi that either develop within living host tissue(biotrophic fungi)or that kill the host cells and then live in the dead tissue(necrotrophic fungi).We adopted a phylogenetic approach to investigate whether these strategies represent evolutionarily stable lifestyles and to elucidate their general phylogenetic *** analysed 163 fungal strains for which we found information on the sequence of the 5.8S rRNA gene and the flanking internal transcribed spacer regions,the identity of the host plant and the concrete phenotypic outcome of the infection.A maximum-Likelihood analysis combined with ancestral character mapping by maximum parsimony revealed that some fungal lineages had switched multiple times between a necrotrophic and an endophytic *** character mapping indicated a minimum of four changes from an endophytic to a necrotrophic lifestyle,four changes in the opposite direction and eight changes among these lifestyles for which the direction could not be determined *** contrast,biotrophs formed five clusters that did not contain necrotrophs or *** biotrophy evolves there is apparently no regression to one of the other two *** conclude that biotrophy usually represents a derived and evolutionarily stable trait,whereas fungi easily can switch between an endophytic and necrotrophic lifestyle at the evolutionary and even the ecological *** experimental studies should focus on the environmental or genetic changes that cause the rapid switches between these two phenotypically different lifestyles.

关键词： Disease expression Fungi Plant pathogens Phylogenetic effects