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Statistical distribution of geomechanical properties and‘Sweet Spots’identification in part of the upper Bakken

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Petroleum Research 2023年第3期8卷 301-308页

作者： Nelson R.K.Tatsipie james j.Sheng Texas Tech University United States

Completions and Reservoir Quality are two key attributes that are used to characterize nonconventional hydrocarbon *** is because,for optimum exploitation of these unconventional assets,horizontal wells need to be drilled in“Sweet Spots”(i.e.,regions where Completions and Reservoir Quality are both superior).One way to quantify these qualities is to use reservoir and geomechanical *** properties can be estimated on a location basis from well logs,and then mapped over terrain using geostatistical *** study presents a‘Sweet Spots’identification workflow based on three performance indexes(Storage Potential Index,Brittleness Index,and Horizontal Stress Index)that can be used to quantify CQ and *** performance indexes are computed from petrophysical property volumes(of Young's Modulus,Bulk Modulus,Shear Modulus,Poisson's Ratio,Minimum Horizontal Stress,Volume of Shale,Total Organic Carbon,Thickness,and Porosity)which are in turn computed from well logs and geostatistical *** the end,the study offers a method to compare the predicted“Sweet Spots”against available production data via their correlation *** resulting reasonable formation property maps,the successful identification of‘Sweet Spots’,and a correlation coefficient of 0.88(between the predicted“Sweet Spots”and well production data)point to the potential of the proposed effort.

关键词： Sweet spots Sequential Gaussian simulation Storage potential index Brittleness index Horizontal stress index

Progressive heterosis in genetically defined tetraploid maize

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journal of Genetics and Genomics 2019年第8期46卷 389-396页

作者： jacob D.Washburn Mitchell j.McElfresh james A.Birchler Division of Biological Sciences University of Missouri

Progressive heterosis, i.e., the additional hybrid vigor in double-cross tetraploid hybrids not found in their single-cross tetraploid parents, has been documented in a number of species including alfalfa,potato, and maize. In this study, four artificially induced maize tetraploids, directly derived from standard inbred lines, were crossed in pairs to create two single-cross hybrids. These hybrids were then crossed to create double-cross hybrids containing genetic material from all four original lines. Replicated fieldbased phenotyping of the materials over four years indicated a strong progressive heterosis phenotype in tetraploids but not in their diploid counterparts. In particular, the above ground dry weight phenotype of double-cross tetraploid hybrids was on average 34% and 56% heavier than that of the single-cross tetraploid hybrids and the double-cross diploid counterparts, respectively. Additionally,whole-genome resequencing of the original inbred lines and further analysis of these data did not show the expected spectrum of alleles to explain tetraploid progressive heterosis under the complementation of complete recessive model. These results underscore the reality of the progressive heterosis phenotype,its potential utility for increasing crop biomass production, and the need for exploring alternative hypothesis to explain it at a molecular level.

关键词： Maize Tetraploid Heterosis Dominance complementation Progressive heterosis

Semi-transparent,flexible,and electrically conductive silicon mesh by capillarity-driven welding of vapor-liquid-solid-grown nanowires over large areas

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Nano Research 2020年第5期13卷 1465-1471页

作者： Thomas A.Celano Seokhyoung Kim David j.Hill james F.Cahoon Department of Chemistry University of North Carolina at Chapel HillChapel HillNC 27599-3290USA

Bottom-up synthesis of semiconductor nanowires(NWs)by the vapor-liquid-solid(VLS)mechanism has enabled diverse technological applications for these *** metallic NWs,however,it has been challenging to form large-area interconnected NW ***,we generate centimeter-scale meshes of mechanically and electrically interconnected Si NWs by sequentially growing,collapsing,and joining the NWs using a capillarity-driven welding *** fabricate meshes from VLS-grown NWs ranging in diameter from 20 to 100 nm and find that the meshes are three-dimensional with a thickness ranging from^1 to^10 microns depending on the NW *** extinction measurements reveal that the networks are semi-transparent with a color that depends on the absorption and scattering characteristics of individual ***,active voltage contrast imaging of both centimeter-and micron-scale meshes reveals widespread electrical *** a sacrificial layer,we demonstrate that the mesh can be liberated from the growth substrate,yielding a highly flexible and transparent *** transport measurements both on the growth substrate and on liberated,flexible films reveal electrical conduction across a centimeter scale with a sheet resistance of^160-180 kΩ/square that does not change significantly upon *** the ability to encode complex functionality in semiconductor NWs through the VLS process,we believe these meshes of networked NWs could find application as neuromorphic memory,electrode scaffolds,and bioelectronic interfaces.

关键词： semiconductor nanowire conductive network flexible electronics welding thermal annealing active-voltage contrast

Absence of Na^+/sugar cotransport activity in Barrett's metaplasia

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World journal of Gastroenterology 2008年第9期14卷 1365-1369页

作者： Lisa j Murray Owen Tully David S Rudolph Marysue Whitby Mary C Valenzano Giancarlo Mercogliano james j Thornton james M Mullin Lankenau Institute for Medical Research WynnewoodPAUnited States Saint Joseph's UniversityDepartment of BiologyPhiladelphiaPA 19096United States Lankenau Hospital Department of Medicine WynnewoodPA 19096United States Lankenau Hospital Department of MedicineWynnewoodPA 19096 United States Lankenau Institute for Medical Research WynnewoodPAUnited States Lankeanu Hospital Division of GastroenterologyWynnewood PA 19096United States Lankeanu Hospital Division of GastroenterologyWynnewoodPA 19096United States

AIM:To evaluate the presence of Na+-dependent, active, sugar transport in Barrett's epithelia as an intestinal biomarker, based on the well-documented, morphological intestinal phenotype of Barrett's esophagus (BE). METHODS: We examined uptake of the nonmeta- bolizable glucose analogue, alpha-methyl-D-glucoside (AMG), a substrate for the entire sodium glucose cotransporter (SGLT) family of transport proteins. During upper endoscopy, patients with BE or with uncomplicated gastroesophageal reflux disease (GERD) allowed for duodenal, gastric fundic, and esophageal mucosal biopsies to be taken. Biopsies were incubated in bicarbonate-buffered saline (KRB) containing 0.1 mmol/L 14C-AMG for 60 min at 20℃. Characterized by abundant SGLT, duodenum served as a positive control while gastric fundus and normal esophagus, known to lack SGLT, served as negative controls. RESULTS: Duodenal biopsies accumulated 249.84 ± 35.49 (SEM) picomoles AMG/μg DNA (n = 12), gastric fundus biopsies 36.20 ± 6.62 (n = 12), normal esophagus 12.10 ± 0.59 (n = 3) and Barrett's metaplasia 29.79 ± 5.77 (n = 8). There was a statistical difference (P < 0.01) between biopsies from duodenum and each other biopsy site but there was no statistically significant difference between normal esophagus and BE biopsies. 0.5 mmol/L phlorizin (PZ) inhibited AMG uptake into duodenal mucosa by over 89%, but had nosignificant effect on AMG uptake into gastric fundus, normal esophagus, or Barrett's tissue. In the absence of Na+ (all Na+ salts replaced by Li+ salts), AMG uptake in duodenum was decreased by over 90%, while uptake into gastric, esophageal or Barrett's tissue was statistically unaffected. CONCLUSION: Despite the intestinal enterocyte phenotype of BE, Na+-dependent, sugar transport activity is not present in these cells.

关键词： Barrett's esophagus Cancer Biomarker Sodium glucose cotransporters Glucose transport Alphamethyl-D-glucoside Phlorizin Esophagus Metaplasia

Estimating geographic variation of infection fatality ratios during epidemics

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Infectious Disease Modelling 2024年第2期9卷 634-643页

作者： joshua Ladau Eoin L.Brodie Nicola Falco Ishan Bansal Elijah B.Hoffman Marcin P.joachimiak Ana M.Mora Angelica M.Walker Haruko M.Wainwright Yulun Wu Mirko Pavicic Daniel jacobson Matthias Hess james B.Brown Katrina Abuabara Departments of Computational Precision Health and Dermatology University of CaliforniaSan FranciscoCA94115USA Arva Intelligence Inc.Salt Lake CityUT84101USA Computational Biosciences Group Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Earth and Environmental Sciences Area Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Graduate Group in Biostatistics University of CaliforniaBerkeleyCA94720USA Biosystems Data Science Environmental Genomics and Systems BiologyLawrence Berkeley National LaboratoryBerkeleyCA94720USA Center for Environmental Research and Community Health(CERCH) School of Public HealthUniversity of CaliforniaBerkeleyCA94720USA Bredesen Center for Interdisciplinary Research and Graduate Education University of TennesseeKnoxvilleTN37996USA Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyBostonMA02139USA Biosciences Oak Ridge National LaboratoryOak RidgeTN37830USA University of California DavisCA95616USA Statistics Department University of CaliforniaBerkeleyCA94720USA Division of Epidemiology and Biostatistics University of California Berkeley School of Public Health2121 Berkeley WayBerkeleyCA94720USA

Objectives We aim to estimate geographic variability in total numbers of infections and infection fatality ratios(IFR;the number of deaths caused by an infection per 1,000 infected people)when the availability and quality of data on disease burden are limited during an *** We develop a noncentral hypergeometric framework that accounts for differential probabilities of positive tests and reflects the fact that symptomatic people are more likely to seek *** demonstrate the robustness,accuracy,and precision of this framework,and apply it to the United States(U.S.)COVID-19 pandemic to estimate county-level SARS-CoV-2 *** The estimators for the numbers of infections and IFRs showed high accuracy and precision;for instance,when applied to simulated validation data sets,across counties,Pearson correlation coefficients between estimator means and true values were 0.996 and 0.928,respectively,and they showed strong robustness to model *** the county-level estimators to the real,unsimulated COVID-19 data spanning April 1,2020 to September 30,2020 from across the U.S.,we found that IFRs varied from 0 to 44.69,with a standard deviation of 3.55 and a median of *** The proposed estimation framework can be used to identify geographic variation in IFRs across settings.

关键词： Infection fatality ratio Infection fatality rate Noncentral hypergeometric distribution COVID-19 SARS-CoV-2

Adenosine-treated bioprinted muscle constructs prolong cell survival and improve tissue formation

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Bio-Design and Manufacturing 2021年第3期4卷 441-451页

作者： Dongxu Ke Adam M.jorgensen Sang j.Lee james j.Yoo Sean V.Murphy Wake Forest Institute for Regenerative Medicine Wake Forest School of MedicineWinston-SalemNCUSA Novaprint Therapeutics Suzhou Co. LtdSuzhouJiangsuChina

It is crucial to maintaining the viability of biofabricated human-sized tissues to ensure their successful survival and function after *** is a purine nucleoside that has the function to suppress cellular metabolism and has been previously proposed as a method to prolong cell viability under *** this study,we optimized the dose concentration of adenosine for incorporation into bioprinted constructs to preserve long-term cell viability in *** results showed that muscle cells(C2C12)containing 6,7,or 8 mM adenosine maintained high cell viability for 20 days under hypoxic conditions(0.1%O2),whereas cells without adenosine treatment showed 100%cell death after 11 *** 20 days under hypoxic conditions,muscle cells treated with adenosine proliferated and differentiated when transferred to normoxic *** these adenosine concentrations,6 mM was picked as the optimized adenosine concentration for further investigations due to its most effective results on improving cell *** bioprinted muscle constructs containing adenosine(6 mM)maintained high cell viability for 11 days under hypoxic conditions,while the control constructs without adenosine had no live *** in vivo validation,the bioprinted constructs with adenosine implanted under the dorsal subcutaneous space in mice,showed the enhanced formation of muscle tissue with minimal central necrosis and apoptosis,when compared to the constructs without *** positive in vitro and in vivo results demonstrate that the use of adenosine is an effective approach to preventing the challenge of hypoxia-induced necrosis in bioprinted tissues for clinical translation.

关键词： Bioprinting Hypoxia Adenosine Cell viability In vivo

A linear regression model (LRM) for groundwater chemistry in and around the Vaniyambadi industrial area, Tamil Nadu, India

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Chinese journal Of Geochemistry 2013年第1期32卷 19-26页

作者： Sajil Kumar P.j. Davis Delson P. Vernon j.G. james E.j. Brandenburg Technical University Cottbus-03046 Germany ITALCONSULT Riyadh-11421 Saudi Arabia Budapest University of Technology and Economics (BME) Budapest-Pf. 91 H-152 Hungary Water Institute Karunya UniversityCoimbatore-641114 India

A linear regression model in conjunction with cluster analysis was applied to the groundwater quality parameters for the Vaniyambadi industrial area, Tamil Nadu, India. These physico-chemical parameters were collected from 25 wells by intensive groundwater sampling conducted during january 2010. All the major ions, pH and electrical conductivity were analyzed. The abundances of cations were in the order of Na jor clusters representing the influence of tanneries and geological formations in the study area, which confirmed the results of major ion chemistry.

关键词：线性回归模型地下水化学工业区印度 LRM 聚类分析物理化学参数研究区域

Impact of source tissue and ex vivo expansion on the characterization of goat mesenchymal stem cells

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journal of Animal Science and Biotechnology 2015年第2期6卷 230-251页

作者： Nuradilla Mohamad-Fauzi Pablo j Ross Elizabeth A Maga james D Murray Department of Animal Science University of California Institute of Ocean and Earth Sciences University of Malaya Department of Population Health and Reproduction University of California

Background： There is considerable interest in using goats as models for genetically engineering dairy animals and also for using stem cells as therapeutics for bone and cartilage repair. Mesenchymal stem cells （MSCs） have been isolated and characterized from various species, but are poorly characterized in goats. Results： Goat MSCs isolated from bone marrow （BM-MSCs） and adipose tissue （ASCs） have the ability to undergo osteogenic, adipogenic and chondrogenic differentiation. Cytochemical staining and gene expression analysis show that ASCs have a greater capacity for adipogenic differentiation compared to BM-MSCs and fibroblasts. Different methods of inducing adipogenesis also affect the extent and profile of adipogenic differentiation in MSCs. Goat fibroblasts were not capable of osteogenesis, hence distinguishing them from the MSCs. Goat MSCs and fibroblasts express CD90, CD105, CD73 but not CD45, and exhibit cytoplasmic localization of OCT4 protein. Goat MSCs can be stably transfected by Nucleofection, but, as evidenced by colony-forming efficiency （CFE）, yield significantly different levels of progenitor cells that are robust enough to proliferate into colonies of integrants following G418 selection. BM-MSCs expanded over increasing passages in vitro maintained karyotypic stability up to 20 passages in culture, exhibited an increase in adipogenic differentiation and CFE, but showed altered morphology and amenability to genetic modification by selection. Conclusions： Our findings provide characterization information on goat MSCs, and show that there can be significant differences between MSCs isolated from different tissues and from within the same tissue. Fibroblasts do not exhibit trilineage differentiation potential at the same capacity as MSCs, making it a more reliable method for distinguishing MSCs from fibroblasts, compared to cell surface marker expression.

关键词： Adipose Bone marrow Characterization Differentiation Goat Mesenchymal stem cells

Overview and comparison of guidelines for management of pancreatic cystic neoplasms

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World journal of Gastroenterology 2019年第31期25卷 4405-4413页

作者： Aws Hasan Kavel Visrodia james j Farrell Tamas A Gonda Division of Digestive and Liver Diseases Department of MedicineColumbia UniversityNew YorkNY 10032United States Division of Digestive Diseases Department of MedicineYale UniversityNew HavenCT 06520United States

Pancreatic cysts are identified at an increasing *** mucinous cystic neoplasms represent a pre-malignant condition,the majority of these lesions do not progress to *** the last 10 years several societies have established guidelines for the diagnosis,initial evaluation and surveillance of these *** we provide an overview of five commonly used guidelines:2015 American Gastroenterological Association,2017 International Association of Pancreatology,American College of Gastroenterology 2018,European Study Group and American College of *** describe the similarities and differences between the methods used to formulate these guidelines,the population they target and their approaches towards initial evaluation and surveillance of cystic lesions.

关键词： Pancreatic cyst surveillance Cyst malignancy Guidelines