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Holed Nanostructures Formed by Aluminum Droplets on a GaAs Substrate

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Nano research 2010年第7期3卷 490-495页

作者： Alvason Zhenhua Li Zhiming M.Wang jiang Wu gregory j.Salamo Institute of Nanoscale Science and Engineering University of ArkansasFayettevilleArkansas 72701USA

We have studied the morphology evolution of holed nanostructures formed by aluminum droplet epitaxy on a GaAs *** outer rings with concentric inner holed rings were ***,an empirical equation to describe the size distribution of the outer rings in the holed nanostructures has been *** contour line generated by the equation provides physical insights into quantum ring formation by droplets of groupⅢmaterials onⅢ-Ⅴsubstrates.

关键词： Droplet epitaxy aluminum droplets MBE GaAs holed nanostructures

Early Cretaceous overprinting of the Mesozoic Daqing Shan fold-and-thrust belt by the Hohhot metamorphic core complex,Inner Mongolia,China

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Geoscience Frontiers 2010年第1期1卷 1-20页

作者： gregory A.Davis Brian j.Darby Department of Earth Sciences University of Southern CaliforniaLos AngelesCA 90089-0740USA ExxonMobil Exploration Company HoustonTXUSA

The Early Cretaceous Hohhot metamorphic core complex （mcc） of the Daqing Shan （Mtns.） of central Inner Mongolia is among the best exposed and most spectacular of the spatially isolated mcc＇s that developed within the northern edge of the North China ＂craton＂. All of these mcc＇s were formed within the basement of a Late Paleozoic Andean-style arc and across older Mesozoic fold-and-thrust belts of variable age and tectonic vergence. The master Hohhot detachment fault roots southwards within the southem margin of the Daqing Shan for an along-strike distance of at least 120 km. Its geometry in the range to the north is complicated by interference patterns between （1） primary, large-scale NW-SE-trend- ing convex and concave fault corrugations and （2） secondary ENE-WSW-trending antiforms and syn- forms that folded the detachment in its late kinematic history. As in the Whipple Mtns. of California, the Hohhot master detachment is not of the Wernicke （1981） simple rooted type; instead, it was spawned from a mid-crustal shear zone, the top of which is preserved as a mylonitic front within Carboniferous metasedimentary rocks in its exhumed lower plate. 4~Ar-39Ar dating of siliceous volcanic rocks in basal sections of now isolated supradetachment basins suggest that crustal extension began at ca. 127 Ma, although lower-plate mylonitic rocks were not exposed to erosion until after ca. 119 Ma. Essentially synchronous cooling of bornblende, biotite, and muscovite in footwall mylonitic gneisses indicates very rapid exhumation and at ca. 122--120 Ma. Contrary to several recent reports, the master detachment clearly cuts across and dismembers older, north-directed thrust sheets of the Daqing Shah foreland fold-and-thrust belt. Folded and thrust-faulted basalts within its foredeep strata are as young as 132.6 ± 2.4 Ma, thus defining within 5--6 Ma the regional tectonic transition between crustal contraction and profound crustal extension.

关键词： North China Yin Shah Daqing Shan Hohhot mcc Cretaceous extension

From common gardens to candidate genes:an elegant case of homoploid hybrid speciation

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Molecular Plant 2021年第2期14卷 200-201页

作者： gregory L.Owens Department of Biology University of VictoriaVictoriaBCCanada

Homoploid hybrid speciation(HHS),where genetic contributions from two species combine to produce a third species without a change in pioidy,remains an intriguing and enigmatic evolutionary *** studies in the past decade have shown that introgression and admixture between species is common,and yet well documented cases of HHS remain rare(Schumer et al.,2014;Marques et al.,2019).This strikes at a key feature of HHS;it is a far higher bar to prove that hybridization was critical for speciation than it is to show that introgression *** former requires us to know how reproductive isolation(rI)is achieved,identify hybrid ancestry,and definitively link hybrid ancestry with reproductive *** this in mind,the work by Wang et al.(2020)fully documenting a case of HHS is particularly impressive in terms of both the scope and clarity of the results.

关键词： al. combine intro

Modelling the smart farm

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Information Processing in Agriculture 2017年第3期4卷 179-187页

作者： Michael j.O’Grady gregory M.P.O’Hare School of Computer Science University College DublinBelfieldDublin 4Ireland Earth Institute University College DublinBelfieldDublin 4Ireland

Smart farming envisages the harnessing of Information and Communication Technologies as an enabler of more efficient,productive,and profitable farming *** technologies do not suffice on their own;rather they must be judiciously combined to deliver meaningful information in near ***-support tools incorporating models of disparate farming activities,either on their own or in combination with other models,offer one popular approach;exemplars include GPFArM,APSIM,GrAZPLAN amongst many *** models tend to be generic in nature and their adoption by individual farmers is *** technologies offer an opportunity to remedy this situation;farm-specific models that can reflect near real-time events become tractable using such *** on the development,and application of farm-specific models is at a very early *** paper thus presents an overview of models within the farming enterprise;it then reviews the state-of the art in smart technologies that promise to enable a new generation of enterprise-specific models that will underpin future smart farming enterprises.

关键词： Smart agriculture Modelling Sensing Internet of things

High Altitude Frogs (rana kukonoris) Adopt a Diversified Bethedging Strategy in the Face of Environmental Unpredictability

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Asian Herpetological research 2018年第1期9卷 43-49页

作者： Wei CHEN Liqing PENG Lichun jIANG David A.PIKE Christopher r.FrIESEN gregory BrOWN Ecological Security and Protection Key Laboratory of Sichuan Province Mianyang Normal University Department of Biology Rhodes College School of Life and Environmental Sciences University of Sydney

Environmental unpredictability can influence strategies of maternal investment among eggs within a clutch. Models predict that breeding females should adopt a diversified bet-hedging strategy in unpredictable environments, but empirical field evidence from Asia is scarce. Here we tested this hypothesis by exploring spatial patterns in egg size along an altitudinal gradient in a frog species （rana kukunoris） inhabiting the Tibetan Plateau. Within-clutch variability in egg size increased as the environment became variable （e.g., lower mean monthly temperature and mean monthly rainfall at higher altitudes）, and populations in environments with more unpredictable rainfall produced eggs that were smaller and more variable in size. We provide support for a diversified bet-hedging strategy in high-altitude environments, which experience dynamic weather patterns and therefore are of unpredictable environmental quality. This strategy may be an adaptive response to lower environmental quality and higher unpredictable environmental variance. Such a strategy should increase the likelihood of breeding success and maximize maternal lifetime fitness by producing offspring that are adapted to current environmental conditions. We speculate that in high-altitude environments prone to physical disturbance, breeding females are unable to consistently produce the optimal egg size due to physiological constraints imposed by environmental conditions （e.g., duration of the active season, food availability）. Species and populations whose breeding strategies are adapted to cope with uncertain environmental conditions by adjusting offspring size and therefore quality show a remarkable degree of ability to cope with future climatic changes.

关键词： altitude bet-hedging strategy environmental quality egg size within-clutch variation unpredictable environment

Optimizing hepatitis C virus treatment through pharmacist interventions: Identification and management of drug-drug interactions

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World journal of Gastroenterology 2017年第9期23卷 1618-1626页

作者： jacob A Langness Matthew Nguyen Amanda Wieland gregory T Everson jennifer j Kiser Hepatology and Transplant Clinic University of Colorado Hospital Department of Pharmacy University of Colorado Hospital University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences Department of Gastroenterology School of MedicineUniversity of Colorado

To quantify drug-drug-interactions (DDIs) encountered in patients prescribed hepatitis C virus (HCV) treatment, the interventions made, and the time spent in this *** standard of care, a clinical pharmacist screened for DDIs in patients prescribed direct acting antiviral (DAA) HCV treatment between November 2013 and july 2015 at the University of Colorado Hepatology Clinic. HCV regimens prescribed included ledipasvir/sofosbuvir (LDV/SOF), paritaprevir/ritonavir/ombitasvir/dasabuvir (OBV/PTV/r + DSV), simeprevir/sofosbuvir (SIM/SOF), and sofosbuvir/ribavirin (SOF/rBV). This retrospective analysis reviewed the work completed by the clinical pharmacist in order to measure the aims identified for the study. The number and type of DDIs identified were summarized with descriptive *** hundred and sixty four patients (83.4% Caucasian, 57% male, average 56.7 years old) were identified; 369 for LDV/SOF, 48 for OBV/PTV/r + DSV, 114 for SIM/SOF, and 133 for SOF/rBV. Fifty-one point five per cent of patients were cirrhotic. Overall, 5217 medications were reviewed (7.86 medications per patient) and 781 interactions identified (1.18 interactions per patient). The number of interactions were fewest for SOF/rBV (0.17 interactions per patient) and highest for OBV/PTV/r + DSV (2.48 interactions per patient). LDV/SOF and SIM/SOF had similar number of interactions (1.28 and 1.48 interactions per patient, respectively). Gastric acid modifiers and vitamin/herbal supplements commonly caused interactions with LDV/SOF. Hypertensive agents, analgesics, and psychiatric medications frequently caused interactions with OBV/PTV/r + DSV and SIM/SOF. To manage these interactions, the pharmacists most often recommended discontinuing the medication (28.9%), increasing monitoring for toxicities (24.1%), or separating administration times (18.2%). The pharmacist chart review for each patient usually took approximately 30 min, with additional time for more complex patients

关键词： Clinical pharmacist Drug-drug interaction Hepatitis C virus treatment

Friction characteristics of confined inflatable structures

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Friction 2014年第4期2卷 365-390页

作者： Eduardo M.SOSA gregory j.THOMPSON Ever j.BArBErO Subhadeep GHOSH Kevin L.PEIL Department of Civil and Environmental Engineering West Virginia UniversityMorgantownWV 26506-6103USA Department of Mechanical and Aerospace Engineering West Virginia UniversityMorgantownWV 26506-6106USA

The availability of high‐strength fabrics and progress in the development of large‐scale inflatable technology made possible the creation of temporary and quickly deployable structures for protection of underground *** structures are relatively lightweight and portable,and can maintain the required rigidity while in *** benefits have prompted the development of inflatable structures for use in confined spaces,such as tunnels and large‐diameter pipes to act as barriers for containing flooding with minimal infrastructure *** work presents experimental results obtained from the evaluation of frictional characteristics of the fabric material that constitute the structural membrane of confined inflatable structures developed for protection of underground transportation tunnels and other large *** tests at coupon level and slippage tests in a reduced‐scale inflatable structure were performed in order to evaluate the frictional characteristics of Vectran *** at coupon level were performed to determine the friction coefficient for different surface types and *** with the reduced‐scale inflatable structure contributed to the understanding of the friction characteristics at system level when subjected to different pressurization or depressurization sequences designed to induce *** results indicate that friction coefficient values at coupon level are about 29 percent higher than values derived from reduced‐scale tests.

关键词： friction fabric materials inflatable structures slippage Vectran

Discrete modeling of a longwall coal mine gob for CFD simulation

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International journal of Mining Science and Technology 2020年第4期30卷 463-469页

作者： Aditya juganda Claire Strebinger jurgen F.Brune gregory E.Bogin Colorado School of Mines GoldenCO 80401USA

One area of concern in longwall coal mines is the active gob directly behind the longwall face,where high concentrations of methane are likely to accumulate and active roof caving *** computational fluid dynamics(CFD)to simulate gas flows in and through the gob,most researchers have represented the entire gob as a porous medium governed by Darcy’s ***,Darcy-type porous flow may not be applicable for the highly porous and unconsolidated fringes of the *** addition,porous medium models do not allow for representative combustion modeling to simulate in-gob ignition and flame *** study presents a hybrid approach to modeling the gob using CFD:the outer part of the gob is modeled as discrete objects that simulate coarse rock rubble,while the gob center is modeled as a porous medium.

关键词： Longwall Coal Computational fluid dynamic Modeling Ventilation

Lactate as a regulator of iron homeostasis

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Life Metabolism 2023年第5期2卷 8-11页

作者： gregory j.Anderson David M.Frazer Iron Metabolism Laboratory QIMR Berghofer Medical Research InstituteBrisbaneQueensland 4006Australia Molecular Nutrition Laboratory QIMR Berghofer Medical Research InstituteBrisbaneQueensland 4006Australia

The key metabolic intermediate lactate can increase expression of the liver-derived peptide hepcidin,the central regulator of body iron homeostasis.A new paper by Liu et *** that lactate achieves this by binding to and activating soluble adenylyl cyclase,thereby increasing cellular cyclic adenosine monophosphate(cAMP)and enhancing signaling through the bone morphogenetic protein(BMP)pathway to modulate hepcidin expression.

关键词： expression thereby homeostasis