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A Dominant Allele of Arabidopsis Pectin-Binding Wall-Associated Kinase Induces a Stress Response Suppressed by MPK6 but Not MPK3 Mutations

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Molecular Plant 2012年第4期5卷 841-851页

作者： bruce D. Kohorn Susan l. Kohorn Tanya Todorova Gillian Baptiste Kevin Stansky Meghan McCullough Department of Biology Bowdoin College ME 04011 USA

The plant cell wall is composed of a matrix of cellulose fibers, flexible pectin polymers, and an array of as- sorted carbohydrates and proteins. The receptor-like Wall-Associated Kinases （WAKs） of Arabidopsis bind pectin in the wall, and are necessary both for cell expansion during development and for a response to pathogens and wounding. Mitogen Activated Protein Kinases （MPKs） form a major signaling link between cell surface receptors and both transcrip- tional and enzyme regulation in eukaryotes, and Arabidopsis MPK6 and MPK3 indeed have important roles in develop- ment and the response to stress and pathogens. A dominant allele of WAK2 requires kinase activity and activates a stress response that includes an increased ROS accumulation and the up-regulation of numerous genes involved in pathogen resistance, wounding, and cell wall biogenesis. This dominant allele requires a functional pectin binding and kinase domain, indicating that it is engaged in a WAK signaling pathway. A null mutant of the major plasma membrane ROS-producing enzyme complex, rbohd/f does not suppress the WAK2cTAP-induced phenotype. A mpk6, but not a mpk3, null allele is able to suppress the effects of this dominant WAK2 mutation, thus distinguishing MPK3 and MPK6, whose activity previously was thought to be redundant. Pectin activation of gene expression is abated in a wak2-null, but is tempered by the WAK-dominant allele that induces elevated basal stress-related transcript levels. The results suggest a mechanism in which changes to the cell wall can lead to a large change in cellular responses and help to explain how pathogens and wounding can have general effects on growth.

关键词： Wall Associated Kinases MPK3 MPK6 pectin oligogalacturonides.

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Selective androgen receptor modulators for the treatment of late onset male hypogonadism

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Asian Journal of Andrology 2014年第2期16卷 256-261,I0009页

作者： Christopher C Coss Amanda jones Michael l Hancock Mitchell S Steiner James T Dalton GTx Inc. Memphis Tennessee USA.

Several testosterone preparations are used in the treatment of hypogonadism in the ageing male. These therapies differ in their convenience, flexibility, regional availability and expense but share their pharmacokinetic basis of approval and dearth of long-term safety data. The brevity and relatively reduced cost of pharmacokinetic based registration trials provides little commercial incentive to develop improved novel therapies for the treatment of late onset male hypogonadism. Selective androgen receptor modulators （SARMs） have been shown to provide anabolic benefit in the absence of androgenic effects on prostate, hair and skin. Current clinical development for SARMs is focused on acute muscle wasting conditions with defined clinical endpoints of physical function and lean body mass. Similar regulatory clarity concerning clinical deficits in men with hypogonadism is required before the beneficial pharmacology and desirable pharmacokinetics of SARMs can be employed in the treatment of late onset male hypogonadism.

关键词： hypogonadism late onset hypogonadism selective androgen receptor modulators testosterone

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AN ANAlYSIS oF THE SHEAR FAIlURE OF RIGID-lINEAR HARDENING BEAMS UNDER IMPUlSIVE lOADING

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Acta Mechanica Sinica 1996年第4期12卷 338-348页

作者：王礼立 Norman jones Ningbo University Ningbo 315211China and also University of Science and Technology of ChinaHefei 230026China Impact Research Centre Department of Mechanical EngineeringUniversity of Liverpool.P.O.Box 147Liverpool L69 3BXU.K.

A theoretical rigid-plastic analysis for the dynamic shear failure of beams under impulsive loading is presented when using a travelling plastic shear hinge model which tabes into account material strain hardening. The maximum dynamic shear strain and shear strain-rate can be predicted in addition to the permanent transverse deflections and other parameters. The conditions for the three modes of shear failure, i.e., excess deflection failure, excess shear strain failure and adiabatic shear failure are analyzed. The special case of an infinitesimally small plastic zone is discussed and compared with Nonaka's solution for a rigid, perfectly plastic material. The results can also be generalized to examine the dynamic response of fibre-reinforced beams.

关键词： shear failure rigid-linear hardening plastic beam dynamic response impulsive loading adiabatic shear

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Do coyotes Canis latrans influence occupancy ot prey in suburban forest fragments？

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Current Zoology 2016年第1期62卷 1-6页

作者： Brandon M. jones Michael V. COVE Marcus A. lASHlEY Victoria l. JACKSON Department of Biology and Agriculture University of Central Missouri Warrensburg M0 64093 USA Department of Applied Ecology North Carolina State University Raleigh NC 27695 USA Department of Forestry and Environmental Resources North Carolina State University Raleigh NC 27695 USA Department of Wildlife Fisheries and Aquaculture Mississippi State University Starkville MS 39762 USA

With the extirpation of apex predators from many North American systems, coyotes Canis latrans have become the de facto top predator and are ubiquitous members of most ecosystems. Keystone predators aid in maintaining ecosystem function by regulating the mammal community through direct predation and instilling the landscape of fear, yet the value of coyotes regulating systems to this capacity is understudied and likely variable across environments. Since coyotes are common in the Midwestern United States, we utilized camera traps and occupancy analyses to as- sess their role in regulating the distribution of mammalian herbivores in a fragmented suburban ecosystem. Forest cover was a strong positive predictor of white-tailed deer Odocoileus virginianus detection, while coyote occurrence had a negative effect. Coyotes exerted a negative effect on squirrel （Sciurus spp.） and eastern cottontail rabbit Sylvilagus floridanus occurrence, while urban cover was a positive predictor for the prey species＇ occurrence. These results suggest all 3 species behaviorally avoid coyotes whereby deer seek denser forest cover and squirrels and cottontails mitigate risk by increasing use of urban areas. Although previous studies reveal limited influence of coyote on the rest of the carnivore guild in suburban systems, we suggest coyotes play an important role in regulating the herbivorous mammals and hence may provide similar eco- logical, benefits in urban/suburban forest fragments through trophic cascades. Furthermore, since hunting may not be allowed in urban and suburban habitats, coyotes might also serve as the pri- mary regulator of nuisance species occurring at high abundance such as white-tailed deer and squirrels.

关键词： camera traps coyote deer rabbit squirrel urban wildlife.

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Gastric emptying, postprandial blood pressure, glycaemia and splanchnic flow in Parkinson's disease

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World Journal of Gastroenterology 2016年第20期22卷 4860-4867页

作者： laurence G Trahair Thomas E Kimber Katerina Flabouris Michael Horowitz Karen l jones Discipline of Medicine The University of Adelaide NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health The University of Adelaide Neurology Unit Royal Adelaide Hospital

AIM: To determine gastric emptying, blood pressure, mesenteric artery blood flow, and blood glucose responses to oral glucose in Parkinson’s ***: Twenty-one subjects (13 M, 8 F; age 64.2 ± 1.6 years) with mild to moderate Parkinson’s disease (Hoehn and Yahr score 1.4 ± 0.1, duration of known disease 6.3 ± 0.9 years) consumed a 75 g glucose drink, labelled with 20 MBq 99mTc-calcium phytate. Gastric emptying was quantified with scintigraphy, blood pressure and heart rate with an automated device, superior mesenteric artery blood flow by Doppler ultrasonography and blood glucose by glucometer for 180 min. Autonomic nerve function was evaluated with cardiovascular reflex tests and upper gastrointestinal symptoms by ***: The mean gastric half-emptying time was 106 ± 9.1 min, gastric emptying was abnormally delayed in 3 subjects (14%). Systolic and diastolic blood pressure fell (P lood flow and blood glucose (P llowing the drink. Three subjects (14%) had definite autonomic neuropathy and 8 (38%) had postprandial hypotension. There were no significant relationships between changes in blood pressure, heart rate or mesenteric artery blood flow with gastric emptying. Gastric emptying was related to the score for autonomic nerve function (R = 0.55, P lationship between the blood glucose at t = 30 min (R = -0.52, P le the blood glucose at t = 180 min was related directly (R = 0.49, P ld to moderate Parkinson’s disease, gastric emptying is related to autonomic dysfunction and a determinant of the glycaemic response to oral glucose.

关键词： Gastric emptying Hypotension Parkinson’ s disease Blood pressure Glucose

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Organic mulching promotes soil organic carbon accumulation to deep soil layer in an urban plantation forest

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Forest Ecosystems 2021年第1期8卷 11-21页

作者： Xiaodan Sun Gang Wang Qingxu Ma Jiahui liao Dong Wang Qingwei Guan Davey l.jones College of Biology and Environment Nanjing Forestry UniversityNanjing 210037China Co-Innovation Center of Sustainable Forestry in Southern China Nanjing 210037China School of Natural Sciences Bangor UniversityGwynedd LL572UWUK College of Environmental Science and Engineering China West Normal UniversityNanchong 637000China UWA School of Agriculture and Environment The University of Western AustraliaPerthWA 6009Australia

Background:Soil organic carbon(SOC)is important for soil quality and fertility in forest *** SOC fractions are sensitive to environmental changes,which reflect the impact of short-term internal and external management measures on the soil carbon *** mulching(OM)alters the soil environment and promotes plant ***,little is known about the responses of SOC fractions in rhizosphere or bulk soil to OM in urban forests and its correlation with carbon composition in ***:A one-year field experiment with four treatments(OM at 0,5,10,and 20 cm thicknesses)was conducted in a 15-year-old ligustrum lucidum *** in the SOC fractions in the rhizosphere and bulk soil;the carbon content in the plant fine roots,leaves,and organic mulch;and several soil physicochemical properties were *** relationships between SOC fractions and the measured variables were ***:The OM treatments had no significant effect on the SOC fractions,except for the dissolved organic carbon(DOC).OM promoted the movement of SOC to deeper soil because of the increased carbon content in fine roots of *** were significant correlations between DOC and microbial biomass carbon and SOC and easily oxidised organic *** OM had a greater effect on organic carbon fractions in the bulk soil than in the *** thinnest(5 cm)mulching layers showed the most rapid carbon decomposition over *** time after OM had the greatest effect on the SOC fractions,followed by soil ***:The frequent addition of small amounts of organic mulch increased SOC accumulation in the present *** is a potential management model to enhance soil organic matter storage for maintaining urban forest productivity.

关键词： Soil organic carbon labile organic carbon fractions Rhizosphere Urban plantation forest Organic mulching

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Approaches to antiretroviral therapy in China

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Cell Research 2005年第Z1期15卷 895-902页

作者： bruce l GIllIAM Robert R REDFIElD Division of Clinical Care and Research Institute of Human Virology University of Maryland Baltimore MD 21201 USA

China has recognized the threat of HIV to its population and responded with a national antiretroviral treatment (ART) program. However, high ART failure rates and the spread of resistance within populations are important realities to consider when developing and managing ART programs in China and worldwide. Concepts which will define treatment success and local and national programmatic goals are 1) access to ART, 2) durability of ART at the patient level, 3) scalability of treatment modalities, and the 4) sustainability of the program at the community or national level. In the face of limited resources, China must also consider when to start ARV therapy, which agents to use, when to switch them, and how to treat highly experienced patients with drug resistance. The optimal ARV regimen to start with is changing frequently with the introduction of new agents and the presentation of new data. Currently, a regimen including tenofovir, emtricitabine or lamivudine and a nonnucleoside reverse transcriptase inhibitor appears to have optimal characteristics to treat HIV/AIDS in China. However, critical to all of these choices is the evaluation of programs implemented to insure wide scale success. China has wisely begun this process of evaluating the perfor- mance of local programs through systematic monitoring and evaluation of treatment outcomes. This will allow regi- mens and programs that work to be expanded, and programs with high failure rates to be eliminated. In the end, evidence based data supporting treatment strategies will allow China to successfully confront its AIDS epidemic early and prevent its tragic consequences

关键词： antiretroviral therapy scalability HIV/AIDS.

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Structural and microstructural description of relaxor-ferroelectric transition in quenched Na_(1/2)Bi_(1/2)TiO_(3)-BaTiO_(3)

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Journal of Materiomics 2022年第4期8卷 823-832页

作者： Andreas Wohninsland Ann-Katrin Fetzer Rachel Broughton Jacob l.jones K.V.lalitha Department of Materials-and Geosciences Technical University of Darmstadt64287DarmstadtGermany Department of Materials Science and Engineering North Carolina State UniversityRaleighNC27695USA

Quenching lead-free Na_(1/2)Bi_(1/2)TiO_(3)-based ceramics from sintering temperature is established to increasethe depolarization temperature,Td and the lattice *** situ synchrotron X-ray diffractionmeasurements were carried out on furnace cooled and quenched Na_(1/2)Bi_(1/2)TiO_(3)-BaTiO_(3)(NBT-BT)with 6and 9 mol.%BT to discern the field-induced ferroelectric *** fractions were determined fromfull pattern Rietveld refinements and utilized together with the change in unit cell volume to calculatevolumetric strain resulting from phase ***-6BT demonstrates a cubic symmetry in thefurnace cooled state but quenching stabilizes the rhombohedral R3c phase and delays the formation of afield-induced,long range-ordered tetragonal phase,thereby shifting the onset of macroscopic strain tohigher fields.A field-induced phase transition from a weakly distorted rhombohedral to tetragonal phasecan be observed in furnace cooled ***,this phase transition cannot be detected inquenched NBT-9BT,since the ferroelectric tetragonal P4mm phase is stabilized in the initial *** to the furnace cooled materials,both the quenched compositions exhibit overall negligiblevolumetric strain as a function of electric ***,scanning electron micrographs of chemi-cally etched,poled and unpoled samples reveal an increased lamellar domain contrast in the *** these findings strengthen the hypothesis of a stabilized ferroelectric order resulting in theabsence of a field-induced phase transformation in quenched NBT-BT.

关键词： lead-free Quenching Na_(1/2)Bi_(1/2)TiO_(3)-BaTiO_(3) Synchrotron diffraction Ferroelectric

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PROBING THE IMPACT OF GAMMA-IRRADIATION ON THE METABOlIC STATE OF NEURAl STEM AND PRECURSOR CEllS USING DUAl-WAVElENGTH INTRINSIC SIGNAl TWO-PHOTON EXCITED FlUORESCENCE

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Journal of Innovative Optical Health Sciences 2011年第3期4卷 289-300页

作者： TATIANA B.KRASIEVA ERICH GIEDZINSKI KATHERINE TRAN MARY lAN CHARlES l.lIMOlI bruce J.TROMBERG laser Microbeam and Medical Program Beckman laser Institute University of California Irvine1002 Health Sciences Road EastIrvineCA 92612USA Department of Radiation Oncology University of California IrvineCalifornia 92697USA

Two-photon excitedfluorescence(TPEF)spectroscopy and imaging were used to investigate the effects of gamma-irradiation on neural stem and precursor cells(NSPCs).While the observed signal from reduced nicotinamide adenine dinucleotide(NADH)was localized to the mitochondria,the signal typically associated with oxidizedflavoproteins(Fp)was distributed diffusely throughout the *** measured TPEF emission and excitation spectra were similar to the established spectra of NAD(P)H and *** intensity was markedly increased by addition of the electron transport chain(ETC)modulator menadione to the medium,along with a concomitant decrease in the NAD(P)H ***-dimensional(3D)neurospheres were imaged to obtain the cellular metabolic index(CMI),calculated as the ratio of Fp to NAD(P)Hfluorescence *** effects were found to differ between low-dose(50 cGy)and high-dose(50 cGy)***-dose irradiation caused a marked drop in CMI values accompanied by increased cellular *** higher doses,both NAD(P)H and Fp signals increased,leading to an overall elevation in CMI *** underscore the complex relationship between radiation dose,metabolic state,and proliferation status in NSPCs and highlight the ability of TPEF spectroscopy and imaging to characterize metabolism in 3D spheroids.

关键词： Multiphoton microscopy cellular metabolic index gamma radiation brain tumors NAD(P)H flavoproteins

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Dynamics of Nitrogen Speciation in Horticultural Soils in Suburbs of Shanghai,China

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Pedosphere 2010年第2期20卷 261-272页

作者： GE Ti-Da HUANG Dan-Feng P. ROBERTS D. l. jones SONG Shi-Wei School of Agriculture and Biology Shanghai Jiao Tong University Shanghai 201101 (China) School of the Environment and Natural Resources University of Wales Bangor Gwynedd LL57 2UW (UK) Key laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academyof Sciences Hunan 410125 (China)

Dissolved organic nitrogen （DON） represents a significant pool of soluble nitrogen （N） in soil ecosystems. Soil samples under three different horticultural management practices were collected from the Xiaxiyang Organic Vegetable and Fruit Farm, Shanghai, China, to investigate the dynamics of N speciation during 2 months of aerobic incubation, to compare the effects of different soils on the mineralization of ^14C-labeled amino acids and peptides, and to determine which of the pathways in the decomposition and subsequent ammonification and nitrification of organic N represented a significant blockage in soil N supply. The dynamics of N speciation was found to be significantly affected by mineralization and immobilization. DON, total free amino acids, and NH^＋-N were maintained at very low levels and did not accumulate, whereas NO3^--N gradually accumulated in these soils. The conversion of insoluble organic N to low-molecular-weight （lMW） DON represented a main constraint to N supply, while conversions of lMW DON to NH4^＋-N and NH4^＋-N to NO3^--N did not. Free amino acids and peptides were rapidly mineralized in the soils by the microbial community and consequently did not accumulate in soil. Turnover rates of the additional amino acids and peptides were soil-dependent and generally followed the order of organic soil 〉 transitional soil 〉 conventional soil. The turnover of high-molecular-weight DON was very slow and represented the major DON loss. Further studies are needed to investigate the pathways and bottlenecks of organic N degradation.

关键词： amino acids dissolved organic N mineralization N transformation peptides

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