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Hydromechanical characterization of gas transport amidst uncertainty for underground nuclear explosion detection

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j.urnal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2019-2032页

作者： Wenfeng Li Chelsea W.neil j.William Carey Meng Meng Luke P.Frash Philip H.Stauffer Earth and Environmental Sciences Los Alamos National LaboratoryLos AlamosNM87544USA Department of Mineral Engineering New Mexico TechSocorroNM87801USA

Given the challenge of definitively discriminating between chemical and nuclear explosions using seismic methods alone,surface detection of signature noble gas radioisotopes is considered a positive identification of underground nuclear explosions(UNEs).However,the migration of signature radionuclide gases between the nuclear cavity and surface is not well understood because complex processes are involved,including the generation of complex fracture networks,reactivation of natural fractures and faults,and thermo-hydro-mechanical-chemical(THMC)coupling of radionuclide gas transport in the *** this study,we provide an experimental investigation of hydro-mechanical(HM)coupling among gas flow,stress states,rock deformation,and rock damage using a unique multi-physics triaxial direct shear rock testing *** testing system also features redundant gas pressure and flow rate measurements,well suited for parameter uncertainty *** porous tuff and tight granite samples that are relevant to historic UNE tests,we measured the Biot effective stress coefficient,rock matrix gas permeability,and fracture gas permeability at a range of pore pressure and stress *** Biot effective stress coefficient varies from 0.69 to 1 for the tuff,whose porosity averages 35.3%±0.7%,while this coefficient varies from 0.51 to 0.78 for the tight granite(porosity<1%,perhaps an underestimate).Matrix gas permeability is strongly correlated to effective stress for the granite,but not for the porous *** experiments reveal the following key engineering implications on transport of radionuclide gases post a UNE event:(1)The porous tuff shows apparent fracture dilation or compression upon stress changes,which does not necessarily change the gas permeability;(2)The granite fracture permeability shows strong stress sensitivity and is positively related to shear displacement;and(3)Hydromechanical coupling among stress states,rock damage,and gas flow appears to be

关键词： Underground nuclear explosion uncertainty quantification Radionuclide transport Biot effective stress coefficient Fracture permeability Matrix permeability

An extra embryonic phase in the true freshwater crab Sinopotamon yangtsekiense Bott,1967(Decapoda,Potamidae)

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Chinese j.urnal of Oceanology and Limnology 2010年第4期28卷 725-730页

作者：吴惠仙薛俊增 CUMBERLIDGE neil Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources(MOE-affiliated) Shanghai Ocean University Department of Biology Northern Michigan University

The true freshwater crabs(Crustacea,Decapoda,Brachyura) are highly adapted to life in freshwater and complete their life cycle entirely independently of sea *** true freshwater crabs exhibit direct development and lack the free-living larval forms(zoea and megalopa) typical of most other *** a prolonged embryonic period(during which they pass through the typical brachyuran larval forms embryologically) the eggs of true freshwater crabs hatch to produce j.venile(hatchling) *** provide here the first report and description of the continuous record of embryonic development from egg-laying up to hatching in the Chinese true freshwater crab Sinopotamon yangtsekiense Bott,1967(Potamoidea,Potamidae).Direct development(complete secondary embryonization) in *** was observed to take 77 days and to include an additional embryonic phase(termed here the egg-j.venile-crab) that occurs in the embryo between the imprisoned megalopa and the newly-emerged j.venile(hatchling) *** is significant because the only other freshwater crab whose embryonic development has been studied in detail is Potamon fluviatilis(Potamidae) which takes 45-47 days and involves only nine embryonic stages.

关键词： true freshwater crab Sinopotamon yangtsekiense embryonic development egg larvae

High-density lipoproteins:an emerging target in the prevention of cardiovascular disease

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Cell Research 2006年第10期16卷 799-808页

作者： Belinda A Cutri neil j.Hime Stephen j.Nicholls The Heart Research Institute CamperdownSydneyNSW 2050Australia Department of Immunology The Scripps Research InstituteLa JollaCA 92037USA Department of Cardiovascular Medicine The Cleveland Clinic FoundationMail Code JJ659500 Euclid AvenueClevelandOH 44195USA

High-density lipoproteins (HDLs) have been well established to protect against the development of atheroscleroticcardiovascular *** has become apparent that in addition to the promotion of reverse cholesterol transport,HDLspossess a number of additional functional properties that may contribute to their beneficial influence on the arterial wall.A number of exciting therapeutic strategies have been developed that target HDL and its ability to protect against thedevelopment of atherosclerotic *** paper will review how the promotion of the functional properties of HDLinhibits the formation of atherosclerotic plaque and stabilises lesions in patients with established disease.

关键词： high-density lipoproteins cardiovascular disease atherosclerotic plaque stabilises lesions

Hyperresolution information and hyperresolution ignorance in modelling the hydrology of the land surface

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Science China Earth Sciences 2015年第1期58卷 25-35页

作者： Keith BEVEN Hannah CLOKE Florian PAPPENBERGER Rob LAMB neil HUNTER Lancaster Environment Centre Lancaster UniversityLancaster LA1 4YQUK and Department of Earth SciencesUppsala UniversityUppsalaSweden Department of Geography and Environmental Science Department of MeteorologyUniversity of ReadingReadingUK European Centre for Medium-range Weather Forecasts ReadingUK School of Geographical Sciences University of BristolBristolUK College of Hydrology and Water Resources Hehai University j.A Trust South BarnBroughton HallSkipton BD23 3AEUK j.A Consulting South BarnBroughton HallSkipton BD23 3AEUK

There is a strong drive towards hyperresolution earth system models in order to resolve finer scales of motion in the *** problem of obtaining more realistic representation of terrestrial fluxes of heat and water,however,is not j.st a problem of moving to hyperresolution grid *** is much more a question of a lack of knowledge about the parameterisation of processes at whatever grid scale is being used for a wider modelling *** grid scales cannot alone solve the problem of this hyperresolution *** paper discusses these issues in more detail with specific reference to land surface parameterisations and flood inundation *** importance of making local hyperresolution model predictions available for evaluation by local stakeholders is *** is expected that this will be a maj.r driving force for improving model performance in the future.

关键词： hyperresolution models epistemic uncertainties models of everywhere communicating uncertainty flood risk

Assessing Chemical Mixtures and Human Health: Use of Bayesian Belief Net Analysis

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j.urnal of Environmental Protection 2012年第6期3卷 462-468页

作者： Anindya Roy neil j. Perkins Germaine M. Buck Louis Department of Mathematics and Statistics University of Maryland Baltimore County Baltimore USA Division of Epidemiology Statistics & Prevention Research Eunice Kennedy Shriver National Institute of Child Health & Human Development Rockville USA

Background: Despite humans being exposed to complex chemical mixtures, much of the available research continues to focus on a single compound or metabolite or a select subgroup of compounds inconsistent with the nature of human exposure. Uncertainty regarding how best to model chemical mixtures coupled with few analytic approaches remains a formidable challenge and served as the impetus for the study. Obj.ctives: To identify the polychlorinated biphenyl (PCB) congener(s) within a chemical mixture that was most associated with an endometriosis diagnosis using novel graphical modeling techniques. Methods: Bayesian Belief Network (BBN) models were developed and empirically assessed in a cohort comprising 84 women aged 18 - 40 years who underwent a laparoscopy or laparotomy between 1999 and 2000;79 (94%) women had serum concentrations for 68 PCB congeners quantified. Adj.sted odds ratios (AOR) for endometriosis were estimated for individual PCB congeners using BBN models. Results: PCB congeners #114 (AOR = 3.01;95% CI = 2.25, 3.77) and #136 (AOR = 1.79;95% CI = 1.03, 2.55) were associated with an endometriosis diagnosis. Combinations of mixtures inclusive of PCB #114 were all associated with higher odds of endometriosis, underscoring its potential relation with endometriosis. Conclusions: BBN models identified PCB congener 114 as the most influential congener for the odds of an endometriosis diagnosis in the context of a 68 congener chemical mixture. BBN models offer investigators the opportunity to assess which compounds within a mixture may drive a human health effect.

关键词： Bayesian Belief Network Endometriosis Environment Mixtures Polychlorinated Biphenyls

Characterization of the tunicamycin gene cluster unveiling unique steps involved in its biosynthesis

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Protein & Cell 2010年第12期1卷 1093-1105页

作者： Wenqing Chen Dongj.ng Qu Lipeng Zhai Meifeng Tao Yemin Wang Shuangj.n Lin neil P.j.Price Zixin Deng Laboratory of Microbial Metabolism and School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200030China National Center for Agricultural Utilization Research(NCAUR) USDA-ARS1815 North University StreetPeoriaIllinois 61604USA College of Pharmacy Wuhan UniversityWuhan 430072China

Tunicamycin,a potent reversible translocase I inhibitor,is produced by several Actinomycetes *** tunicamycin structure is highly unusual,and contains an 11-carbon dialdose sugar and anα,β-1″,11′-glycosidic *** we report the identification of a gene cluster essential for tunicamycin biosynthesis by high-throughput heterologous expression(HHE)strategy combined with a *** of the genes into heterologous non-producing Streptomyces hosts results in production of tunicamycin by these strains,demonstrating the role of the genes for the biosynthesis of *** disruption experiments coupled with bioinformatic analysis revealed that the tunicamycin gene cluster is minimally composed of 12 genes(tunA–tunL).Amongst these is a putative radical SAM enzyme(Tun B)with a potentially unique role in biosynthetic carbon-carbon bond ***,a seven-step novel pathway is proposed for tunicamycin ***,two gene clusters for the potential biosynthesis of tunicamycin-like antibiotics were also identified in Streptomyces clavuligerus ATCC 27064 and Actinosynnema mirums DSM *** data provide clarification of the novel mechanisms for tunicamycin biosynthesis,and for the generation of new-designer tunicamycin analogs with selective/enhanced bioactivity via combinatorial biosynthesis strategies.

关键词： tunicamycin biosynthetic gene cluster high-throughput heterologous expression bioassay combinatorial biosynthesis

Functional group resolved NMR relaxation of 3-carbon adsorbates in mesoporous alumina

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Magnetic Resonance Letters 2023年第3期3卷 248-255,I0004页

作者： neil Robinson Carmine D’Agostino Michael Lj.hns Department of Chemical Engineering The University of Western Australia35 Stirling HighwayPerthWA 6009Australia Department of Chemical Engineering The University of ManchesterOxford RoadManchesterM139PLUK Dipartimento di Ingegneria Civile ChimicaAmbientale e Dei Materiali(DICAM)Alma Mater Studiorum e Universita di BolognaVia Terracini28Bologna40131Italy

NMR relaxation analysis provides a unique and non-invasive probe of fluid dynamics within porous materials,and may be applied to the interpretation of a wide variety of material and interfacial ***,we report two-dimensional^(1)H T_(1)-T_(2)relaxation correlation measurements of a range of three-carbon adsorbates(1-propanol,2-propanol and propanoic acid)imbibed within the mesoporous metal oxide *** data,acquired across field strengths of 2 MHz,12.7 MHz and 43 MHz,clearly reveal two populations in each measurement,identified as the alkyl and hydroxyl moieties of each *** results expand the range of materials in which such functional group resolved relaxation is known to occur,and demonstrate the clear persistence of such phenomena using a range of typical benchtop NMR systems employed to study fluid-saturated porous media.

关键词： NMR relaxation Adsorption Porous media Low-field NMR

Changes during late-stage embryonic development from egg-j.venile to free-living hatchling in Chinese freshwater crab Sinopotamon yangtsekiense (Decapoda, Brachyura, Potamidae)

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Chinese j.urnal of Oceanology and Limnology 2013年第3期31卷 542-551页

作者：薛俊增刘艳 neil CUMBERLIDGE 吴惠仙 Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources Shanghai Ocean University Department of Biology Northern Michigan UniversityMarquette

This study expands on recent reports that direct development in the Chinese potamid freshwater crab Sinopotamon yangtsekiense involves the completion of all brachyuran larval stages (nauplius, zoea, and megalopa) inside the egg case during embryonic development. Detailed studies of embryonic development in this species revealed the presence of an additional larval stage (the egg-j.venile) between the megalopa and the free-living hatchling crab. We described and compared the appendages of the head, thorax, and abdomen of the egg-j.venile with those of the hatchling crab in S. yangtsekiense. Significant differences were found between most of the appendages of these two stages with a soft exoskeleton in the egg-j.venile, no j.int articulation, a slimmer appearance, and a lack of setae when compared with the newly emerged free-living hatchling crab. These modifications of the appendages are related to the confinement within the egg case of the egg-megalopa and egg-j.venile during direct development, and the need for the free-living hatchling freshwater crab to move, feed, and respire. In marine crabs, the megalopa gives rise to the first crab stage whereas in freshwater crabs the egg-j.venile follows the megalopa and immediately precedes the free-living first crab stage.

关键词： Sinopotamon yangtsekiense freshwater crab embryonic development egg-j.venile hatchlingcrab appendage

Ampullary cancer of intestinal origin and duodenal cancer-A logical clinical and therapeutic subgroup in periampullary cancer

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World j.urnal of Gastrointestinal Oncology 2017年第10期9卷 407-415页

作者： Manj. D Chandrasegaram Anthony j.Gill j.s Samra Tim Price j.hn Chen j.nathan Fawcett neil D Merrett the Prince Charles Hospital School of Medicine University of Queensland Sydney Medical School University of Sydney Cancer Diagnosis and Pathology Group Kolling Institute of Medical Research Royal North Shore Hospital Department of Surgery Royal North Shore Hospital Queen Elizabeth Hospital University of Adelaide Flinders Medical Centre Royal Adelaide Hospital Princess Alexandra Hospital Department of Upper GI Surgery Bankstown Hospital Discipline of Surgery Western Sydney University

Periampullary cancers include pancreatic, ampullary, biliary and duodenal cancers. At presentation, the maj.rity of periampullary tumours have grown to involve the pancreas, bile duct, ampulla and duodenum. This can result in difficulty in defining the primary site of origin in all but the smallest tumors due to anatomical proximity and architectural distortion. This has led to variation in the reported proportions of resected periampullary cancers. Pancreatic cancer is the most common cancer resected with a pancreaticoduodenectomy followed by ampullary(16%-50%), bile duct(5%-39%), and duodenal cancer(3%-17%). Patients with resected duodenal and ampullary cancers have a better reported median survival(29-47 mo and 22-54 mo) compared to pancreatic cancer(13-19 mo). The poorer survival with pancreatic cancer relates to differences in tumour characteristics such as a higher incidence of nodal, neural and vascular invasion. While small ampullary cancers can present early with biliary obstruction, pancreatic cancers need to reach a certain size before biliary obstruction ensues. This larger size at presentation contributes to a higher incidence of resection margin involvement in pancreatic cancer. Ampullary cancers can be subdivided into intestinal or pancreatobiliary subtype cancers with histomolecular staining. This avoids relying on histomorphology alone, as even some poorly differentiated cancers preserve the histomolecular profile of their mucosa of origin. Histomolecular profiling is superior to anatomic location in prognosticating survival. Ampullary cancers of intestinal subtype and duodenal cancers are similar in their intestinal origin and form a logical clinical and therapeutic subgroup of periampullary cancers. They respond to 5-FU based chemotherapeutic regimens such as capecitabine-oxaliplatin. Unlike pancreatic cancers, KRAS mutation occurs in only approximately a third of ampullary and duodenal cancers. Future clinical trials should group ampullary cancer

关键词： Periampullary cancer Pancreatobiliary subtype Intestinal subtype Ampullary cancer Duodenal cancer Epidermal growth factor receptor Pancreatic cancer Chemotherapy Pancreaticoduodenectomy KRAS