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A NEW DIRECT DISCONTINUOUS GAlERKIN METHOD WITH SYMMETRIC STRUCTURE FOR NONlINEAR DIFFUSION EQUATIONS

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Journal of Computational Mathematics 2013年第6期31卷 638-662页

作者： chad Vidden Jue Yan Department of Mathematics Iowa State University Ames IA USA

In this paper we continue the study of discontinuous Galerkin finite element methods for nonlinear diffusion equations following the direct discontinuous Galerkin （DDG） meth- ods for diffusion problems [17] and the direct discontinuous Galerkin （DDG） methods for diffusion with interface corrections [18]. We introduce a numerical flux for the test func- tion, and obtain a new direct discontinuous Galerkin method with symmetric structure. Second order derivative jump terms are included in the numerical flux formula and explicit guidelines for choosing the numerical flux are given. The constructed scheme has a sym- metric property and an optimal l2 （l2） error estimate is obtained. Numerical examples are carried out to demonstrate the optimal （k ＋ 1）th order of accuracy for the method with pk polynomial approximations for both linear and nonlinear problems, under one-dimensional and two-dimensional settings.

关键词： Discontinuous Galerkin Finite Element method Diffusion equation Stability,Convergence.

A tri-layer approach to controlling nanopore formation in oxide supports

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Nano Research 2019年第6期12卷 1223-1228页

作者： Abha A.Gosavi James l.Hedrick Peng-Cheng Chen Justin M.Notestein chad A.Mirkin Department of Chemical and Biological Engineering Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA International Institute for Nanotechnology Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA Department of Materials Science and Engineering Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA Department of Chemistry Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA

A novel tri-layer approach for immobilizing metal nanoparticles in SiO2 supports is *** this work,we show that under rapid heating to temperatures of approximately 1,000 ℃,metal nanoparticles less than 15 nm in size will entrench in the SiO2 layer on a silicon wafer to create pores as deep as 250 *** studied and characterized this entrenching behavior and subsequent nanopore formation for a wide variety of metal nanoparticles,including Au,Ag,Pt,Pd,and *** also demonstrate that an Al2O3 layer acts as a barrier to such pore ***,by creating a tri-layer architecture consisting of SiO2 on Al2O3 on silicon wafers,we can control the depth to which nanoparticles entrench between 3-5 *** small range allows one to entrench particles for the purpose of immobilization but still present them above the *** two advances of moving into the sub-15 nm size regime and of controlled particle immobilization through entrenchment have important implications in studying site-isolated and stabilized metal nanoparticles for applications in sensing,separations,and catalysis.

关键词： nanopore formation nanoparticle entrenchment nanoparticle stabilization atomic force microscopy Au nanoparticles

Reproduction and beyond,kisspeptin in ruminants

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Journal of Animal Science and Biotechnology 2015年第3期6卷 264-268页

作者： Joseph A.Daniel chad D.Foradori Brian K.Whitlock James l.Sartin Department of Animal Science Berry College Department of Anatomy Physiology & PharmacologyAuburn University Department of large Animal Clinical Sciences University of Tennessee

Kisspeptin （Kp） is synthesized in the arcuate nucleus and preoptic area of the hypothalamus and is a regulator of gonadotropin releasing hormone in the hypothalamus. In addition, Kp may regulate additional functions such as increased neuropeptide Y gene expression and reduced proopiomelanocortin （POMC） gene expression in sheep. Other studies have found a role for Kp to release growth hormone （GH）, prolactin and luteinizing hormone （lH） from cattle, rat and monkey pituitary cells. Intravenous injection of Kp stimulated release lH, GH, prolactin and follicle stimulating hormone in some experiments in cattle and sheep, but other studies have failed to find an effect of peripheral injection of Kp on GH release. Recent studies indicate that Kp can stimulate GH release after intracerebroventricular injection in sheep at doses that do not release GH after intravenous injection. These studies suggest that Kp may have a role in regulation of both reproduction and metabolism in sheep. Since GH plays a role in luteal development, it is tempting to speculate that the ability of Kp to release GH and lH is related to normal control of reproduction.

关键词： Growth hormone leptin luteinizing Neuropeptide Y POMC

Incorporating within- and between-patch resource selection in identification of critical habitat for brood-rearing greater sage-grouse

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Ecological Processes 2015年第1期4卷 57-71页

作者： Matthew R Dzialak chad V Olson Stephen l Webb Seth M Harju Jeffrey B Winstead Hayden-Wing Associates LLCNatural Resource ConsultantsLaramieWY 2308 South 8th StreetUSA The Samuel Roberts Noble Foundation 2510 Sam Noble ParkwayArdmoreOK 73401USA

Introduction:Incorporating information on animal behavior in resource-based predictive modeling(e.g.,occurrence mapping)can elucidate the relationship between process and spatial pattern and depict habitat in terms of its structure as well as its *** this paper,we assigned location data on brood-rearing greater sage-grouse(Centrocercus urophasianus)to either within-patch(encamped)or between-patch(traveling)behavioral modes by estimating a movement-based relative displacement *** were to estimate and validate spatially explicit models of within-versus between-patch resource selection for application in habitat management and compare these models to a non-behaviorally adjusted ***:A single model,the vegetation and water resources model,was most plausible for both the encamped and traveling modes,including the non-behaviorally adjusted *** encamped,sage-grouse selected for taller shrubs,avoided bare ground,and were closer to mesic *** sage-grouse selected for greater litter cover and herbaceous *** for proximity to mesic areas was common to both encamped and traveling modes and to the non-behaviorally adjusted *** non-behaviorally adjusted map was similar to the encamped model and validated ***,we observed different selection patterns during traveling that could have been masked had behavioral state not been accounted ***:Characterizing habitat that structured between-patch movement broadens our understanding of the habitat needs of brood-rearing sage-grouse,and the combined raster surface offers a reliable habitat management tool that is readily amenable to application by GIS users in efforts to focus sustainable landscape management.

关键词： Behavioral mode Brood-rearing Centrocercus urophasianus Conditional logistic regression Conservation planning Information-theoretic approach Relative displacement index Species occurrence model

Atrazine removal from water by activated charcoal cloths

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International Soil and Water Conservation Research 2020年第2期8卷 205-212页

作者： Javier M.Gonzalez lynnette R.Murphy chad J.Penn Veera M.Boddu laura l.Sanders National Soil Erosion Research laboratory USDA-ARSWest LafayetteIN47907USA Earth Science Department Northeastern Illinois UniversityChicagoIL60625USA O’Neill School of Public and Environmental Affairs University of IndianaBloomingtonIN47405USA Plant Polymer Research Unit National Center for Agriculture Utilization ResearchUSDA-ARSPeoriaIL61604USA

Pollution control structures may be adapted to enhance the removal of nutrients and pesticides from water. Charcoal-like material is known to sorb organic compounds in solution, including atrazine, a herbicide used to control broadleaf weeds, which persists in soils and can migrate from soils to water bodies, ultimately affecting water quality. The primary goal of this study was to investigate if activated charcoal cloths (single-weave, SW;double-weave, DW;and knitted, KT) are more efficient to remove atrazine from aqueous solutions than a cloth without activated charcoal (control) currently used in pollution control structures. The approach consisted of sorption kinetics, flow-through, and desorption/degradation experiments using 50 and 1000μg l-1 atrazine solutions. Results showed that within 30 min of contact time, the control sorbed from 22.6 to 36.1% of atrazine in solution;whereas the activated charcoal cloths sorbed from 76 to 99% of atrazine in solution (SW > KT > DW). The flow-through ex-periments showed that the SW sorbed 88.2, 76.1, and 52.2%of atrazine at the contact time of 0.75, 5, and 10 min, respectively. After 28 days of incubation, previously sorbed atrazine on the SW cloth did not degrade and lts showed that activated charcoal cloths are a practical alternative for improving atrazine removal in water in pollution control structures.

关键词： Atrazine Activated charcoal Water quality Pesticide Cloth

landscape features and weather influence nest survival of a ground-nesting bird of conservation concern,the greater sage-grouse,in humanaltered environments

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Ecological Processes 2012年第1期1卷 83-97页

作者： Stephen l Webb chad V Olson Matthew R Dzialak Seth M Harju Jeffrey B Winstead Dusty lockman Hayden-Wing Associates LLC2308 South 8th StreetLaramieWY82070USA KC Harvey Environmental LLC376 Gallatin Park DriveBozemanMT59715USA

Introduction:Ground-nesting birds experience high levels of nest ***,birds can make selection decisions related to nest site location and characteristics that may result in physical,visual,and olfactory impediments to ***:We studied daily survival rate[DSR]of greater sage-grouse(Centrocercus urophasianus)from 2008 to 2010 in an area in Wyoming experiencing large-scale alterations to the *** used generalized linear mixed models to model fixed and random effects,and a correlation within nesting attempts,individual birds,and ***:Predation of the nest was the most common source of nest failure(84.7%)followed by direct predation of the female(13.6%).Generally,landscape variables at the nest site(≤30 m)were more influential on DSR of nests than features at larger spatial *** of shrub canopy cover at the nest site(15-m scale)and distances to natural gas wells and mesic areas had a positive relationship with DSR of nests,whereas distance to roads had a negative relationship with DSR of *** added to the vegetation model,maximum wind speed on the day of nest failure and a 1-day lag in precipitation(i.e.,precipitation the day before failure)improved model fit whereby both variables negatively influenced DSR of ***:Nest site characteristics that reduce visibility(i.e.,shrub canopy cover)have the potential to reduce depredation,whereas anthropogenic(i.e.,distance to wells)and mesic landscape features appear to facilitate ***,predators may be more efficient at locating nests under certain weather conditions(i.e.,high winds and moisture).

关键词： behavior Centrocercus urophasianus conservation depredation generalized linear mixed models greater sage-grouse human development management nest survival weather

Changing the paradigm：the potential for targeted therapy in laryngeal squamous cell carcinoma

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Cancer Biology & Medicine 2016年第1期13卷 87-100页

作者： Megan l.ludwig Andrew C.Birkeland Rebecca Hoesli Paul Swiecicki Matthew E.Spector J.chad Brenner Department of Otolaryngology Head and Neck SurgeryUniversity of Michigan Medical SchoolAnn ArborMI 48109USA Cellular and Molecular Biology Program University of MichiqanAnn ArborMI 48109USA Department of Hematology Oncology University of Michigan Medical SchoolAnn ArborMI 48109USA Comprehensive Cancer Center University of Michigan Medical SchoolAnn ArborMI 48109USA

laryngeal squamous cell carcinoma(lSCC) remains a highly morbid and fatal disease. Historically, it has been a model example for organ preservation and treatment stratification paradigms. Unfortunately, survival for lSCC has stagnated over the past few decades. As the era of next-generation sequencing and personalized treatment for cancer approaches, lSCC may be an ideal disease for consideration of further treatment stratification and personalization. Here, we will discuss the important history of lSCC as a model system for organ preservation, unique and potentially targetable genetic signatures of lSCC, and methods for bringing stratified, personalized treatment strategies to the 21^(st) century.

关键词： Head and neck cancer laryngeal squamous cell carcinoma genetics targeted therapy personalized medicine

Microbial Reduction of Graphene Oxide by Shewanella

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Nano Research 2011年第6期4卷 563-570页

作者： Gongming Wang Fang Qian chad W. Saltikov Yongqin Jiao Yat li Department of Chemistry and Biochemistry University of California 1156 High Street Santa Cruz CA 95064 USA Physical and life Sciences Directorate Lawrence Livermore National Laboratory Livermore CA 94550 USA Department of Microbiology and Environmental Toxicology University of California 1156 High Street Santa Cruz CA 95064 USA

Graphene oxide （GO） can be reduced to graphene in a normal aerobic setup under ambient conditions as mediated by microbial respiration of Shewanella cells. The microbially-reduced graphene （MRG） exhibited excellent electrochemical properties. Extracellular electron transfer pathways at the cell/GO interface were systematically investigated, suggesting both direct electron transfer and electron mediators are involved in the GO reduction.

关键词： Electrogenic bacterial graphene green synthesis extracellular electron transfer

Material transport in dip-pen nanolithography

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Frontiers of physics 2014年第3期9卷 385-397页

作者： Keith A. Brown Daniel J. Eichelsdoerfer Xing liao Shu He chad A. Mirkin Department of Chemistry Northwestern University 2145 Sheridan Road Evanston IL 60208 USA International Institute for Nanotechnology Northwestern University 2145 Sheridan Road Evanston IL 60208 USA Department of Materials Science and Engineering Northwestern University 2145 Sheridan Road Evanston IL 60208 USA

Dip-pen *** （DPN） is a useful method for directly printing materials on surfaces with sub-50nm resolution. Because it, involves the physical transport of materials from a scanning probe tip to a surface and the subsequent chemical interaction of that material with the surface, there are many factors to consider when attempting to understand DPN. In this review, we overview the physical and chemical processes that are known to play a role in DPN, Through a detailed review of the literature, we classify inks into three general categories based on their transport properties, and highlight the myriad ways that. DPN can be used to perform chemistry at the tip of a scanning probe.

关键词： dip-pen nanolithography scanning probe lithography materials transport