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Matter and Radiation at Extremes 2020年第1期5卷 16-22页

作者： Joseph Nilsen Andrea L.Kritcher Madison EMartin Robert E.Tipton heather d.whitley damian C.Swift Tilo doppner Benjamin L.Bachmann Amy E.Lazicki Natalie B.Kostinski Brian R.Maddox Gilbert W.Collins Siegfried H.Glenzer Roger W.Falcone Lawrence Livermore National Laboratory LivermoreCalifornia 94551USA University of Rochester RochesterNew York 14627USA SLAC National Accelerator Menlo ParkCalifornia 94025USA University of California Berkeley BerkeleyCalifornia 94720USA

Over the last six years many experiments have been done at the National Ignition Facility to measure the Hugoniot of materials,such asCHplastic at extreme pressures,up to 800 ***“Gbar”design employs a strong spherically converging shock launched through a solid ball of material using a hohlraum radiation *** shock front conditions are characterized using x-ray *** this paper we examine the role of radiation in heating the unshocked material in front of the shock to understand the impact it has on equation of state measurements and how it drives the measured data off the theoretical Hugoniot *** particular,the two main sources of radiation heating are the preheating of the unshocked material by the high-energy kilo-electron-volt x-rays in the hohlraum and the heating of the material in front of the shock,as the shocked material becomes hot enough to radiate *** our model,we estimate that preheating can reach 4 eV in unshocked material,and that radiation heating can begin to drive data off the Hugoniot significantly,as pressures reach above 400 Mb.

关键词： spherical equation radiative

Navigating the dynamic landscape of alpha-synuclein morphology: a review of the physiologically relevant tetrameric conformation

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Neural Regeneration Research 2020年第3期15卷 407-415页

作者： heather R.Lucas Ricardo d.Fernández department of Chemistry Virginia Commonwealth University

N-acetylatedα-synuclein(αSyn)has long been established as an intrinsically disordered protein associated with a dysfunctional role in Parkinson’s *** recent years,a physiologically relevant,higher order conformation has been identified as a helical tetramer that is tailored by buried hydrophobic interactions and is distinctively aggregation *** canonical mechanism by which the tetramer assembles remains *** novel biochemical approaches,computational methods,pioneering purification platforms,and powerful imaging techniques continue to develop,puzzling information that once sparked debate as to the veracity of the tetramer has now shed light upon this new counterpart inαSyn *** magnetic resonance and computational studies on multimericαSyn structure have revealed that the protein folding propensity is controlled by small energy barriers that enable large scale ***,familial mutations ablate tetramerization and reconfigure polymorphic *** this review,we will discuss the dynamic landscape ofαSyn quaternary structure with a focus on the tetrameric conformation.

关键词： alpha-synuclein amyloid fibrils intrinsically disordered protein multimer N-acetylation oligomer Parkinson’s disease protein folding protein structure tetramer

Comparison of cross sectional optical coherence tomography images of elevated optic nerve heads across acquisition devices and scan protocols

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Eye and Vision 2018年第1期5卷 163-171页

作者： Megh d.Patel Fareshta Khushzad heather E.Moss department of Ophthalmology Stanford University2370 Watson Courtsuite 200Palo AltoCA 94303USA department of Neurology and Neurological Sciences Stanford University2370 Watson Courtsuite 200Palo AltoCA 94303USA

Background:Optic nerve head measurements extracted from optical coherence tomography(OCT)show promise for monitoring clinical conditions with elevated optic nerve *** aim of this study is to compare reliability within and between raters and between image acquisition devices of optic nerve measurements derived from OCT scans in eyes with varying degrees of optic nerve ***:Wide angle line scans and narrow angle radial scans through optic nerve heads were obtained using three spectral domain(Sd)OCT devices on 5 subjects(6 swollen optic nerves,4 normal optic nerves).Three raters independently semi-manually segmented the internal limiting membrane(ILM)and Bruch’s membrane(BM)on each scan using customized *** rater segmented each scan *** were qualitatively and quantitatively ***-rater,intra-rater and inter-device reliability was assessed for the optic nerve cross sectional area calculated from the ILM and BM segmentations using intraclass correlation coefficients and graphical ***:Line scans from all devices were qualitatively *** scans for which frame rate could not be adjusted were of lower ***-rater reliability for segmentation and optic nerve cross sectional area was better than inter-rater reliability,which was better than inter-device reliability,though all ICC exceeded *** was not impacted by the degree of optic nerve ***:Sd-OCT devices acquired similar quality scans of the optic nerve head,with choice of scan protocol affecting the *** image derived markers,variability between devices was greater than that attributable to inter and intra-rater differences.

关键词： Optic nerve head Optical coherence tomography Bruch’s membrane Inner limiting membrane Comparison

An examination of the population dynamics of syngnathid fishes within Tampa Bay,Florida,USA

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Current Zoology 2010年第1期56卷 118-133页

作者： heather d.MASONJONES Emily ROSE Lori Benson McRAE danielle L.dIXSON Biology department University of Tampa Biology department Texas A & M University School of Marine and Tropical Biology James Cook University

Seagrass ecosystems worldwide have been declining, leading to a decrease in associated fish populations, especially those with low mobility such as syngnathids （pipefish and seahorses）. This two-year pilot study investigated seasonal patterns in density, growth, site fidelity, and population dynamics of Tampa Bay （FL） syngnathid fishes at a site adjacent to two marinas under construction. Using a modified mark-recapture technique, fish were collected periodically from three closely located sites that varied in seagrass species （Thalassia spp., Syringodium spp., and mixed-grass sites） and their distance from open water, but had consistent physical/chemical environmental characteristics. Fish were marked, photographed for body size and gender measurements, and released the same day at the capture site. Of the 5695 individuals surveyed, 49 individuals were recaptured, indicating a large, flexible population. Population density peaks were observed in July of both years, with low densities in late winter and late summer. Spatially, syngnathid densities were highest closest to the mouth of the bay and lowest near the shoreline. Seven species of syngnathid fishes were observed, and species-specific patterns of seagrass use emerged during the study. However, only two species, Syngnathus scovelli and Hippoeampus zosterae, were observed at high frequencies. For these two species, body size decreased across the study period, but while S. scovelli＇s population density decreased, H. zosterae＇s increased. Across six of the seven species, population size declined over the course of this preliminary study; however, seasonal shifts were impossible to distinguish from potential anthropogenic effects of construction [Current Zoology 56 （1）： 118-133, 2010].

关键词： Syngnathids Habitat-use Seahorse Pipefish Population density Mark-recapture

Scattering and diffraction of plane P-waves in a 2-d elastic half-space Ⅱ：shallow arbitrary shaped canyon

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 459-485页

作者： heather P.Brandow Vincent Lee Civil and Environmental Engineering University of Southern California Los Angeles 90089 United States

Scattering and diffraction of elastic in-plane P-and SV-waves by a surface topography such as an elastic canyon at the surface of a half-space is a classical problem which has been studied by earthquake engineers and strong-motion seismologists for over forty years. The case of out-of-plane SH waves on the same elastic canyon that is semi-circular in shape on the half-space surface is the first such problem that was solved by analytic closed form solutions over forty years ago by Trifunac. The corresponding case of in-plane P-and SV-waves on the same circular canyon is a much more complicated problem because, the in-plane P-and SV-scattered waves have different wave speeds and together they must have zero normal and shear stresses at the half-space surface. It is not until recently in 2014 that analytic solution for such problem is found by the author in the work of Lee and Liu. This paper uses the technique of Lee and Liu of defining these stress-free scattered waves to solve the problem of the scattered and diffraction of these in-plane waves on an almost-circular surface canyon that is arbitrary in shape.

关键词： diffraction elastic P-waves SV-waves weighted-residual method arbitrary-shaped canyon

A systematic review of randomized controlled trials examining the effectiveness of saffron(Crocus sativus L.) on psychological and behavioral outcomes

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Journal of Integrative Medicine 2015年第4期13卷 231-240页

作者： heather Ann Hausenblas Kacey Heekin heather Lee Mutchie Stephen Anton department of Kinesiology Jacksonville University department of Aging & Geriatric Research University of Florida

BACKGROUNd：Throughout the past three decades,increased scientifi c attention has been given to examining saffron’s（Crocus sativus L.）use as a potential therapeutic or preventive agent for a number of health conditions,including cancer,cardiovascular disease,and ***：The purpose of this systematic review is to examine and categorize the current state of scientifi c evidence from randomized controlled trials（RCTs）regarding the effi cacy of saffron on psychological/behavioral *** STRATEGY：Electronic and non-electronic systematic searches were conducted to identify all relevant human clinical research on *** search strategy was extensive and was designed according to the＂Preferred Reporting Items for Systematic Reviews and Meta-Analyses（PRISMA）.＂Reference lists of articles that met the inclusion criteria were *** English language studies were *** CRITERIA：Saffron trials in combination with other substances and saffron safety studies were considered,in accordance with the PRISMA *** studies must have a control *** studies must measure a physiological and/or a behavioral *** EXTRACTION ANd ANALYSIS：The methodological quality of all included studies was independently evaluated by two reviewers using the Jadad *** scores and P-values of measures were compared both inter-and intra-study for each parameter（i.e.,depression）.RESULTS：Twelve studies met our inclusion *** studies examined the effects of saffron on psychological/behavioral outcomes of：major depressive disorder（n=6）,premenstrual syndrome（n=1）,sexual dysfunction and infertility（n=4）,and weight loss/snacking behaviors（n=1）.The data from these studies support the effi cacy of saffron as compared to placebo in improving the following conditions：depressive symptoms（compared to anti-depressants and placebo）,premenstrual symptoms,and sexual *** addition,saffron use was also effective in reducing exce

关键词： Crocus health-rela ted outcomes systematic review

Virus-Induced Gene Silencing in the Culinary Ginger （Zingiber officinale）： An Effective Mechanism for down-Regulating Gene Expression in Tropical Monocots

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Molecular Plant 2009年第5期2卷 1084-1094页

作者： Tanya Renner Jennifer Bragg heather E. driscoll Juliana Cho Andrew O. Jackson Chelsea d. Specht department of Plant and Microbial Biology University of California Berkeley CA 94720 USA Present address: Genornics and Gene discovery USDA ARS PWA WRRC-GGD 800 Buchanan Street Albany CA 94710 USA

Virus-induced gene silencing （VIGS） has been shown to be effective for transient knockdown of gene expression in plants to analyze the effects of specific genes in development and stress-related responses. VlGS is well established for studies of model systems and crops within the Solanaceae, Brassicaceae, Leguminaceae, and Poaceae, but only recently has been applied to plants residing outside these families. Here, we have demonstrated that barley stripe mosaic virus （BSMV） can infect two species within the Zingiberaceae, and that BSMV-VIGS can be applied to specifically down-regulate phytoene desaturase in the culinary ginger Zingiber officinale. These results suggest that extension of BSMV-VlGS to monocots other than cereals has the potential for directed genetic analyses of many important temperate and tropical crop species.

关键词： Barley stripe mosaic virus virus-induced gene silencing VIGS Zingiber officinale Monocot.

Clinical trial perspective for adult and juvenile Huntington's disease using genetically-engineered mesenchymal stem cells

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Neural Regeneration Research 2016年第5期11卷 702-705页

作者： Peter deng Audrey Torrest Kari Pollock heather dahlenburg Geralyn Annett Jan A.Nolta Kyle d.Fink Stem Cell Program and Institute for Regenerative Cures University of California Davis Health System

Progress to date from our group and others indicate that using genetically-engineered mesenchymal stem cells（MSC） to secrete brain-derived neurotrophic factor（BdNF） supports our plan to submit an Investigational New drug application to the Food and drug Administration for the future planned Phase 1 safety and tolerability trial of MSC/BdNF in patients with Huntington＇s disease（Hd）. There are also potential applications of this approach beyond Hd. Our biological delivery system for BdNF sets the precedent for adult stem cell therapy in the brain and could potentially be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis（ALS）, spinocerebellar ataxia（SCA）, Alzheimer＇s disease, and some forms of Parkinson＇s disease. The MSC/BdNF product could also be considered for studies of regeneration in traumatic brain injury, spinal cord and peripheral nerve injury. This work also provides a platform for our future gene editing studies, since we will again use MSCs to deliver the needed molecules into the central nervous system.

关键词： mesenchymal stem cells neurodegenerative disorders, Huntington's disease genetic engineering brain derived neurotrophic factor

Porphyria cutanea tarda as a complication of therapy for chronic hepatitis C

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World Journal of Gastroenterology 2008年第38期14卷 5913-5915页

作者： James Azim heather McCurdy Richard H Moseley division of Gastroenterology department of Internal Medicine department of Veterans Affairs Medical Center and University of Michigan School of Medicine Ann ArborMichigan United States

There is a strong association between porphyria cutanea tarda (PCT) and chronic viral hepatitis C. Therapy for chronic viral hepatitis C may improve PCT. However, there are only a few reports of the de novo development of PCT during therapy for chronic viral hepatitis C. We describe the development of PCT in a 56-year-old patient with chronic viral hepatitis C after 12 wk of peginterferon/ribavirin therapy. In addition, the patient was homozygous for the H63d hereditary hemochromatosis gene (HFE ) mutation. The association of PCT with chronic viral hepatitis C and the possible role of hepatic iron overload and ribavirin-induced hemolytic anemia in the development of PCT during therapy for chronic viral hepatitis C are discussed.

关键词： Porphyria Hepatitis C virus Ribavirin Pegylated interferon Hemochromatosis

Impact of colorectal cancer screening participation in remote northern Canada:A retrospective cohort study

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World Journal of Gastroenterology 2020年第48期26卷 7652-7663页

作者： heather A Smith Andrew d Scarffe Nicole Brunet Cait Champion Kami Kandola Alisha Tessier Robin Boushey Craig Kuziemsky department of Surgery University of OttawaOttawa K1Y4E9OntarioCanada Telfer School of Management University of OttawaOttawa K1N6N5OntarioCanada Faculty of Medicine University of OttawaOttawa K1Y4E9OntarioCanada department of Surgery Northern Ontario School of MedicineSudbury P3E2C6OntarioCanada department of Health and Social Services Government of the Northwest TerritoriesYellowknife X1A1P5Northwest TerritoriesCanada department of Surgery Stanton Territorial Health AuthorityYellowknife X1A0H1Northwest TerritoriesCanada division of General Surgery University of OttawaOttawa K1H 8L6OntarioCanada Office of Research Services MacEwan UniversityEdmonton T5J4S2AlbertaCanada

BACKGROUNd Screening provides earlier colorectal cancer(CRC)detection and improves *** remains poorly understood if these benefits are realized with screening guidelines in remote northern populations of Canada where CRC rates are nearly twice the national average and access to colonoscopy is *** To evaluate the participation and impact of CRC screening guidelines in a remote northern *** This retrospective cohort study included residents of the Northwest Territories,a northern region of Canada,age 50-74 who underwent CRC screening by a fecal immunohistochemical test(FIT)between January 1,2014 to March 30,*** assess impact,individuals with a screen-detected CRC were compared to clinically-detected CRC cases for stage and location of CRC between *** assess participation,we conducted subgroup analyses of FIT positive individuals exploring the relationships between signs and symptoms of CRC at the time of screening,wait-times for colonoscopy,and screening *** sample Welch t-test was used for normally distributed continuous variables,Mann-Whitney-Wilcoxon Tests for data without normal distribution,and Chi-square goodness of fit test for categorical variables.A P value ofdered to be statistically *** 6817 fecal tests were completed,meaning an annual average screening rate of 25.04%,843(12.37%)were positive,629 individuals underwent a follow-up colonoscopy,of which,24.48%had advanced neoplasia(AN),5.41%had *** were no significant differences in stage,pathology,or location between screen-detected cancers and clinically-detected *** assessing participation and screening outcomes,we observed 49.51%of individuals referred for colonoscopy after FIT were ineligible for CRC screening,most often due to signs and symptoms of *** were more likely to have AN if they had signs and symptoms of cancer at the time of screening,waited over 180 d for colonoscopy,or were indigenous[

关键词： Gastroenterology Rural health services Public health Colorectal neoplasms Early detection of cancer Northwest Territories