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Eight decades of compositional change in a managed northern hardwood landscape

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Forest Ecosystems 2023年第3期10卷 398-410页

作者： Mark J.Ducey Olivia L.Fraser Mariko Yamasaki Ethan p.Belair william B.Leak University of New Hampshire Department of Natural Resources and the Environment114 James HallDurhamNH03824USA U.S.D.A.Forest Service White Mountain National Forest71 White Mountain DriveCamptonNH03223USA U.S.D.A.Forest Service Northern Research Station271 Mast RoadDurhamNH03824USA The Nature Conservancy Natural Climate SolutionsAfrica Regional Portland Office45 Exchange StSuite 303PortlandME04101USA

We analyzed over 8 decades of change in forest composition(represented by species proportion of basal area)and size class from more than 400 permanent plots located on the Bartlett Experimental Forest in the White Mountains of New *** data represent one of the longest-term landscape-scale records of forest change based on permanent plots in North *** analyzed the plots based on elevation class,land type indicating assumed successional direction(grouped into coniferous and deciduous),and inventory period within managed and unmanaged portions of the *** ongoing shift from small-to large-diameter stems is clear across all species,in response to the overall aging of the forest following exploitative harvesting in the 19th *** compositional changes include a continuing decline in shade-intolerant species(paper birch and aspen),along with the mid-tolerant yellow *** increase in red maple abundance through the early 1990s has leveled off or *** shade-tolerant species,increases in beech and red spruce were largely consistent with assumed land type on unmanaged plots,but heavy marking against diseased beech on managed plots restricted increase of that *** maple declined in abundance except where silvicultural intervention helped maintain *** contrast,eastern hemlock showed a continuing expansion at all elevations below 600 *** data continue to show little or no evidence of upward migration of species,despite evidence of recent regional change in ***,the BEF is poised for substantial changes when emerald ash borer and hemlock woolly adelgid,both of which are known to infest nearby areas,do arrive.

关键词： Northern hardwoods Succession Stand dynamics Silviculture

Helicobacter pylori vacA s1a and s1b alleles from clinical isolates from different regions of Chile show a distinct geographic distribution

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World Journal of Gastroenterology 2005年第40期11卷 6366-6372页

作者： MI Díaz A Valdivia p Martínez JL palacios p harris J Novales E Garrido D Valderrama C Shilling A Kirberg E Hebel J Fierro R Bravo F Siegel G Leon G Klapp A Venegas Departamento de Genética Molecular y Microbiología. pontificia Universidad Católica de Chile. Santiago Departamento de pediatría Centro de Diagnóstico Terapéutico Los Angeles Unidad de Gastroenterología Anatomía patológica Centro de Endoscopía Quirúrgica Hospital Base de Linares Hospital Regional de Valdivia Instituto de Bioquímica Hospital Regional de punta Arenas

AIM： To establish the most common vacA alleles in Helicobacter pylori （ H pylon） strains isolated from Chilean patients and its relationship with gastritis and gastroduodenal ulcers, METHODS： Two hundred and forty five Hpyloriclinical isolates were obtained from 79 biopsies from Chilean infected patients suffedng from gastrointestinal diseases. An average of 2-3 strains per patient was isolated and the vac4 genotype was analyzed by pCR and 3% agarose electrophoresis. Some genotypes were checked by DNA sequencing. RESULTS： The most prevalent vacA genotype in Chilean patients was slb ml （76%）, followed by sla ml （21%）. In oontrast, the s2 m2 genotype was scarcely represented （3%）. The slb ml genotype was found most frequently linked to gastropathies （p〈0.05） rather than ulcers. Ulcers were found more commonly in male and older patients. Curiously, patents IMng in dties located North and far South of Santiago, thecapital and largest Chilean city, carried almost exclusively strains with the slb ml genotype. In contrast, patients from Santiago and cities located South of Santiago carded strains with either one or both sla ml and slb ml genotypes. Regarding the s2 m2 genotype, comparison with GenBank sequences revealed that Chilean s2 sequence was identical to those of Australian, American, and Colombian strains but quite different from those of Alaska and India. CONCLUSION： Differences in geographic distribution of the s and m vacA alleles in Chile and a relationship of slb ml genotype with gastritis were found. Sequence data in part support a hispanic origin for the vacA genotype. Asymmetric distribution of genotypes slb ml and s2 m2 recedes H pyloristrain distribution in Spain and portugal.

关键词： Hpylori vacA alleles Chilean isolates s1 s2 m1 and m2 sequences

Dynamic knee valgus kinematics and their relationship to pain in women with patellofemoral pain compared to women with chronic hip joint pain

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Journal of Sport and Health Science 2019年第5期8卷 486-493页

作者： Eric Schmidt Marcie harris-Hayes Gretchen B.Salsich program in physical Therapy Washington University School of MedicineSt.LouisMO 63108USA program in physical Therapy Department of Physical Therapy and Athletic TrainingSaint Louis UniversitySt.LouisMO 63104USA Department of Orthopaedic Surgery Washington University School of MedicineSt.LouisMO 63108USA

Background:Dynamic knee valgus(DKV)is an abnormal movement pattern visually characterized by excessive medial movement of the lower extremity during weight *** in hip and knee kinematic components of DKV may explain the emergence of different pain problems in people who exhibit the same observed movement *** a secondary analysis of exiting data sets,we sought to determine whether hip and knee frontal and transverse plane angles during a functional task differed between women with patellofemoral pain and women with chronic hip joint pain and the relationship between joint-specific kinematics and pain in these 2 pain ***:In the original studies,3-dimensional hip and knee kinematics during a single-limb squat were obtained in 20 women with patellofemoral pain and 14 women with chronic hip joint pain who demonstrated visually classified *** intensity during the squat was assessed in both *** the secondary analysis,kinematic data were compared between pain groups using their respective control groups as a *** each pain group,correlation coefficients were used to determine the relationship between kinematics and pain during the ***:Hip adduction and contralateral pelvic drop were greater in those with chronic hip joint pain compared to those with patellofemoral pain(effect sizes ≥0.40).Greater knee external rotation(r= 0.47,p= 0.04)was correlated with greater knee pain in those with patellofemoral pain,while greater hip adduction(r = 0.53,p = 0.05)and greater hip internal rotation(r = 0.55,p = 0.04)were correlated with greater hip pain in those with chronic hip joint ***:Hip frontal plane motion was greater in those with chronic hip joint pain compared to those with patellofemoral *** both groups,greater abnormal movement at the respective joint(e.g.,knee external rotation in the patellofemoral pain group and hip adduction and internal rotation in the chronic hip joint pain gro

关键词： Anterior knee pain syndrome Femoroacetabular impingement Hip joint Kinematics Knee joint Single-limb squat

A new perspective on quiet Sun magnetism

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Science China(physics,Mechanics & Astronomy) 2009年第11期52卷 1660-1664页

作者： LITES Bruce william High Altitude Observatory National Center for Atmospheric ResearchP.O. Box 3000 Boulder CO 80307 USA

The Hinode mission has provided us with a new, quantitative view of the magnetism of the quiet Sun. It has revealed that the quiet internetwork areas are blanketed by horizontal fields that appear at first sight to have more flux than the vertical fields resolved on the same 0.3 size scale. These measurements point to the possibility that the horizontal fields might be the primary source of the "hidden turbulent flux" of the quiet Sun anticipated from Hanle effect depolarization. In this paper, evidence is presented suggesting that the "seething" horizontal fields observed by Harvey in 2007 and the horizontal fields revealed by Hinode are the same phenomenon. Because the seething fields appear to be of uniform fluctuation over the whole disk, the phenomenon is most likely not associated with the dynamo source of solar activity. Thus, the small-scale "hidden turbulent flux" lends support to the notion of a local solar dynamo acting on granular sizes and time scales.

关键词： Sun magnetism fields granulation

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

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Journal 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(porosityperhaps 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

Whole-body heat exposure induces membrane changes in spermatozoa from the cauda epididymidis of laboratory mice

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Asian Journal of Andrology 2010年第4期12卷 591-598页

作者： Harsha Wechalekar Brian p. Setchell Eleanor J. peirce Mario Ricci Chris Leigh william G. Breed Discipline of Anatomy and pathology School of Medical Sciences Faculty of Health Sciences University of Adelaide Adelaide South Australia 5005 Australia Division of Health Sciences University of South Australia City East Campus Adelaide South Australia 5000 Australia

This study was carried out to determine if exposure to hot environmental temperatures had a direct, detrimental effect on sperm quality. For this the effect of whole-body heat exposure on epididymal spermatozoa of laboratory mice was investigated. C57BL/6 mice （n = 7） were housed in a microclimate chamber at 37℃-38℃ for 8 h per day for three consecutive days, while control mice （n = 7） were kept at 23℃-24℃. Cauda epididymal spermatozoa were obtained 16 h after the last heat treatment. The results showed that sperm numbers were similar in the two groups （p = 0.23）, but after heat treatment, a significant reduction in the percentage of motile sperm was present （p 〈 0.0001）. Membrane changes of the spermatozoa were investigated by staining with phycoerythrin （pE）- conjugated Annexin V, which detects exteriorization of phosphotidylserine from the inner to the outer leaflet of the sperm plasma membrane, and 7-aminoactinomycin D （7-AAD）, which binds to the sperm nucleus when the plasma membrane is damaged. The percentage of spermatozoa showing positive staining with Annexin V-pE or 7-AAD or both, was significantly higher （p 〈 0.05） in heat-exposed mice compared with controls. These results show that whole-body heat exposure to 37℃-38℃ induces membrane changes in the epididymal spermatozoa of mice, which may lead to apoptosis.

关键词： laboratory mice sperm membrane damage whole-body heat

Tomato Ovary-to-Fruit Transition is Characterized by a Spatial Shift of mRNAs for Cell Wall Invertase and its Inhibitor with the Encoded proteins Localized to Sieve Elements

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Molecular plant 2015年第2期8卷 315-328页

作者： william M. palmer School of Environmental and Life Sciences The University of Newcastle NSW 2308 Callaghan Australia Australia-China Research Centre for Crop Improvement The University of Newcastle NSW 2308 Callaghan Australia Institute of plant physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 300 Fenglin Road Shanghai 200032 China These authors contributed equally to the article. present address: College of Life Sciences. Central China Normal University Wuhan 430079 China

Central to understanding fruit development is to elucidate the processes mediating a successful transition from pre-pollination ovaries to newly set fruit, a key step in establishing fruit yield potential. In tomato, cell wall invertase （CWIN） LIN5 and its inhibitor INH1 are essential for fruit growth. However, the molecular and cellular basis by which they exert their roles in ovary-to-fruit transition remains unknown. To address this issue, we conducted a study focusing on ovaries and fruitlets at 2 days before and 2 days after anthesis, respectively. In situ hybridization analyses revealed that LIN5 and INH1 exhibited a dispersed expression in ovaries compared with their phloem-specific expression in fruitlets. Remarkably, LIN5 and INH1 proteins were immunologically co-localized to cell walls of sieve elements （SEs） in ovaries immediately prior to anthesis and in young fruitlets, but were undetectable in provascular bundles of younger ovaries. A burst in CWlN activity occurred during ovary-to-fruit transition. Interestingly, the ovaries, but not the fruit- lets, exhibited high expression of a defective invertase, SldeCWIN1, an ortholog of which is known to enhance inhibition of INH on CWlN activity in tobacco. Imaging of a fluorescent symplasmic tracer indicated an apoplasmic phloem unloading pathway operated in ovaries, contrary to the previously observed symplasmic unloading pathway in fruit pericarp. These new data indicate that （1） a phloem-specific patterning of the CWIN and INH mRNAs is induced during ovary-to-fruit transition, and （2） LIN5 protein functions specifically in walls of SEs and increases its activity during ovary-to-fruit transition, probably to facilitate phloem unloading and to generate a glucose signal positively regulating cell division, hence fruit set.

关键词： fruit set invertase invertase inhibitor phloem unloading sugar signaling

Exercise during weight loss improves hepatic mitophagy

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Sports Medicine and Health Science 2022年第3期4卷 183-189页

作者： Megan E.Rosa-Caldwell Kaylee E.poole Andrew Seija Matthew p.harris Nicholas p.Greene Joshua S.Wooten Cacheixia Research Laboratory Exercise Science Research CenterDepartment of HealthHuman Performanceand RecreationUniversity of ArkansasFayettevilleARUSA Department of Neurology Beth Israel Deaconess Medical CenterBostonMAUSA Department of Applied Health Southern Illinois University EdwardsvilleEdwardsvilleILUSA

Non-alcoholic fatty liver disease(NAFLD)has recently become a public health concern concurrent with the obesity *** work has shown aberrant mitochondrial content/quality and autophagy in models of NAFLD,whereas exercise is known to improve these *** purpose of this study was to examine the effect of different weight-loss modalities on hepatic mitochondrial content,autophagy and mitophagy in ***-eight male C57BL/6J mice were divided into 1 of 4 groups:low fat diet(LFD,10%fat,18 weeks),high fat diet(HFD,60%fat diet,18 weeks),weight-loss by diet(D,60%fat diet for 10 weeks then 10%fat diet for 8 weeks)or weight-loss by diet and physical activity(D/pA,60%fat diet for 10 weeks,then 10%fat diet plus a running wheel for 8 weeks).Immunoblot data were analyzed by one-way analysis of variance(ANOVA)with significance denoted at pprotein contents were approximately 50%less in HFD compared to LFD.D/pA had 50%more BNIp3 compared to ***1 content was 40%higher in D and D/pA compared to ***/pARKIN levels were 40%lower in HFD,D,and D/pA compared to *** p-UbSer65 was 3-fold higher in ***3II/I ratio was 50%greater in HFD and D/pA,yet p62 protein content was 2.5 fold higher in ***-fat diet causes disruptions in markers of mitochondrial quality *** activity combined with diet were able to ameliorate these derangements and seemingly improve hepatic mitochondrial quality above control values.

关键词： Autophagy High-fat diet Mitochondria Hepatic metabolism

A Dialectal Chinese Speech Recognition Framework

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Journal of Computer Science & Technology 2006年第1期21卷 106-115页

作者：李净郑方 william Byrne Dan Jurafsky Center for Speech Technology State Key Laboratory of Intelligent Technology and Systems Department of Computer Science and Technology Tsinghua University Beijing 100084 P.R. China Machine Intelligence Laboratory Cambridge University U.K. Center for Language and Speech processing The Johns Hopkins University U.S.A. Department of Linguistics Stanford University U.S.A.

A framework for dialectal Chinese speech recognition is proposed and studied, in which a relatively small dialectal Chinese （or in other words Chinese influenced by the native dialect） speech corpus and dialect-related knowledge are adopted to transform a standard Chinese （or putonghua, abbreviated as pTH） speech recognizer into a dialectal Chinese speech recognizer. Two kinds of knowledge sources are explored： one is expert knowledge and the other is a small dialectal Chinese corpus. These knowledge sources provide information at four levels： phonetic level, lexicon level, language level, and acoustic decoder level. This paper takes Wu dialectal Chinese （WDC） as an example target language. The goal is to establish a WDC speech recognizer from an existing pTH speech recognizer based on the Initial-Final structure of the Chinese language and a study of how dialectal Chinese speakers speak putonghua. The authors propose to use contextindependent pTH-IF mappings （where IF means either a Chinese Initial or a Chinese Final）, context-independent WDC-IF mappings, and syllable-dependent WDC-IF mappings （obtained from either experts or data）, and combine them with the supervised maximum likelihood linear regression （MLLR） acoustic model adaptation method. To reduce the size of the multipronunciation lexicon introduced by the IF mappings, which might also enlarge the lexicon confusion and hence lead to the performance degradation, a Multi-pronunciation Expansion （MpE） method based on the accumulated uni-gram probability （AUp） is proposed. In addition, some commonly used WDC words are selected and added to the lexicon. Compared with the original pTH speech recognizer, the resulting WDC speech recognizer achieves 10-18% absolute Character Error Rate （CER） reduction when recognizing WDC, with only a 0.62% CER increase when recognizing pTH. The proposed framework and methods are expected to work not only for Wu dialectal Chinese but also for other dialectal Chinese languages and

关键词： dialectal Chinese speech recognition initial or final (IF) IF-mapping rule pronunciation modeling small quantity of speech data