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Effects of experimental season of prescribed fire and nutrient addition on structure and function of previously grazed grassland

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Journal of Plant Ecology 2018年第4期11卷 576-584页

作者： elizabeth h.boughton Patrick J.Bohlen Julia h.Maki MacArthur Agro-ecology Research Center 300 Buck Island Ranch RoadLake PlacidFL 33852USA University of Central Florida Biology 4110 Libra DriveOrlandoFL 32816USA School of Natural Resources and Environment University of Florida103 Black HallPO Box 116455GainesvilleFL 32611USA

Aims Understanding the drivers of grassland structure and function fol-lowing livestock removal will inform grassland restoration and ***,we investigated the effects of fire and nutri-ent addition on structure and function in a subtropical semi-native grassland recently released from grazing in south-central *** examined responses of soil nutrients,plant tissue nutrients,bio-mass of live,standing dead and litter,and plant species composi-tion to experimental annual prescribed fire applied during different seasons(wet season *** season),and nutrient additions(N,P and N+P)over 9 *** Experimental plots were set up in a randomized block split-plot design,with season of prescribed fire as the main treatment and nutrient addition as the subplot *** cover data were collected annually from 2002 to 2011 and plant tissue and plant biomass data were collected in 2002-2006 and *** nutrients were analyzed in 2004,2006 and *** Findings Soil total phosphorus(P)levels increased substantially with P addition but were not influenced by prescribed *** of P and N led to increased P and N concentrations in live plant tissues,but prescribed fire reduced N in live *** of tissue N were higher in all plots at the beginning of the exper-iment,an effect that was likely due to grazing activity prior to removal of *** tissue N steadily declined over time in all plots,with annually burned plots declining faster than unburned *** fire was an important driver of standing dead and litter biomass and was important for main-taining grass biomass and percent *** addition was also important:the addition of both N and P was associated with greater live biomass and woody *** of grazing,lack of prescribed fire,and addition of N+P led to a reduction of grass biomass and a large increase in biomass of a woody *** prescribed fire promoted N loss from the system by reducing

关键词： grassland nutrient enrichment nutrient limitation prescribed fire productivity

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Quantification of changes in zero valent iron morphology using X-ray computed tomography

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Journal of Environmental Sciences 2013年第11期25卷 2344-2351页

作者： Ping Luo elizabeth h.Bailey Sacha J.Mooney Division of Agricultural and Environmental Sciences School of Biosciences University of Nottingham Sutton Bonington CampusSutton Bonington

Morphological changes within the porous architecture of laboratory scale zero valent iron （ZVI） permeable reactive barriers （PRBs）, after exposure to different groundwater conditions, have been quantified experimentally for different ZVI/sand ratios （10%, 50% and 100%, W/W） with the aim of inferring porosity changes in field barriers. Column studies were conducted to simulate interaction with different water chemistries, a synthetic groundwater, acidic drainage and deionised （DI） water as control. Morphological changes, in terms of pore size and distribution, were measured using X-ray computed tomography （CT）. CT image analysis revealed significant morphological changes in columns treated with different water chemistries. For example, 100% ZVI （W/W） columns had a higher frequency of small pores （0.6 mm） was observed in ZVI grains reacted with typical groundwater, resulting in a porosity of 27%, compared to 32% when exposed to DI water. In comparison, ZVI grains treated with the acidic drainage had higher porosity （44%） and larger average pore size （2.8 mm）. 10% ZVI PRB barrier material had the highest mean porosity （56%） after exposure to any water chemistry whilst 100% ZVI （W/W） columns always had the lowest （34%） with the 50% ZVI （W/W） in between （40%）. These results agree with previously published PRB field data and simultaneously conducted geochemical monitoring and mass balance calculation, indicating that both the geochemical and hydraulic environment of the PRB play an important role in determining barrier lifespan. This study suggests that X-ray CT image analysis is a powerful tool for studying the detailed inter pores between ZVI grains within PRBs.

关键词： porosity change X-ray computer tomography mass balance permeable reactive barrier zero valent iron acidic drainage typical groundwater pore-clogging

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Opportunities to increase soil carbon sequestration in grazing lands in the southeastern United States

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Grassland Research 2024年第1期3卷 69-78页

作者： Maria L.Silveira Priscila Junia Rodrigues da Cruz Joao Mauricio Bueno Vendramini Elizabeth.boughton Rosvel Bracho Abmael da Silva Cardoso Range Cattle Research and Education Center University of FloridaOnaFloridaUSA Archbold Biological Station Lake PlacidFloridaUSA School of Forest Fisheriesand Geomatics SciencesUniversity of FloridaGainesvilleFloridaUSA

Background:Grazing lands provide numerous ecosystem services,including the capacity to store large amounts of soil carbon(C);however,our understanding of the factors affecting soil C responses to management is ***:In this paper,we synthesized information about the impacts of grazing land management on soil C within the southeastern region of the United ***:Most studies(68%)demonstrated that proper management increased soil C stocks with an average C accumulation rate of 1.4 Mg C ha-1 *** remaining(32%)studies showed no effect of management on soil *** of the studies reported negative impacts of management on soil *** largest increase in soil C(8 Mg C ha-1 year-1)was associated with the conversion of cropland to pastureland while overseeding legumes into grass pastures resulted in the lowest C sequestration rates(0.2 Mg C ha-1 year-1).Conclusions:Considering the rates of soil C accretion and the extensive area occupied by grazing lands,data in this synthesis conﬁrm that the adoption of improved management practices can increase soil C sequestration in the southeastern United *** addition,because most improved management practices can also have co-beneﬁts,they may be favorable for forage and livestock production and other ecosystem services.

关键词： grazing management pasture soil carbon

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Oximes： Unrecognized Chameleons in Genera and Specialized Plant Metabolism

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Molecular Plant 2018年第1期11卷 95-117页

作者： Mette S rensen elizabeth h.J. Neilson Birger Lindberg Moiler Plant Biochemistry Laboratory Department of Plant and Environmental Sciences University of Copenhagen Thorvaldsensvej 40 Frederiksberg C Copenhagen Denmark VILLUM Center for Plant Plasticity University of Copenhagen Thorvaldsensvej 40 Frederiksberg C Copenhagen Denmark Center for Synthetic Biology University of Copenhagen Thorvaldsensvej 40 Frederiksberg C Copenhagen Denmark

Oximes （R1R2C=NOh） are nitrogen-containing chemical constituents that are formed in species representing all kingdoms of life. In plants, oximes are positioned at important metabolic bifurcation points between general and specialized metabolism. The majority of plant oximes are amino acid-derived metabolites formed by the action of a cytochrome P450 from the CYP79 family. Auxin, cyanogenic glucosides, glucosinolates, and a number of other bioactive specialized metabolites including volatiles are produced from oximes. Oximes with the E configuration have high biological activity compared with Z-oximes. Oximes or their derivatives have been demonstrated or proposed to play roles in growth regulation, plant defense, pollinator attraction, and plant communication with the surrounding environment. In addition, oxime-derived products may serve as quenchers of reactive oxygen species and storage compounds for reduced nitrogen that may be released on demand by the activation of endogenous turnover pathways. As highly bioactive molecules, chemically synthesized oximes have found versatile uses in many sectors of society, especially in the agro- and medical sectors. This review provides an update on the structural diversity, occurrence, and biosynthesis of oximes in plants and discusses their role as key players in plant general and specialized metabolism.

关键词： structural diversity CYP79 auxin cyanogenic glucosides volatile organic compounds E-oxime Z-oxime

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Retinal nerve fiber layer changes based on historic CD4 nadir among hIV positive patients undergoing glaucoma evaluation

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International Journal of Ophthalmology(English edition) 2019年第5期12卷 789-794页

作者： Sarah h.Van Tassel Paul Petrakos elizabeth Marlow elizabeth Mauer harjot K.Singh Anna M.Demetriades Department of Ophthalmology Weill Cornell Medicine Division of Biostatistics and Epidemiology Department of Healthcare Policy & ResearchWeill Cornell Medicine Division of Infectious Disease New York-Presbyterian Hospital/Weill Cornell Medicine

AIM: To determine relationships between retinal nerve fiber layer(RNFL) thickness and nadir CD4 cell count in human immunodeficiency virus(hIV) positive patients evaluated for glaucoma ***: Data were reviewed for 329 hIV positive patients evaluated for glaucoma suspicion. high-definition optical coherence tomography(OCT) RNFL measurements were obtained at least 6 mo apart. Analyses were performed to identify relationships between nadir CD4 count and RNFL ***: Totally 110 eyes of 55 patients met inclusion criteria, of which 46 eyes were from subjects with nadir CD4had nadir CD4≥200 cells/mm^3. Patients with nadir CD4had significantly thicker superior(119.7±18.6 μm) and temporal(63.8±11.7 μm) quadrants at time of initial OCT compared to the superior(112.8±16.8 μm, P=0.048) and temporal(57.1±11.9 μm, P=0.004) quadrants of patients with higher nadir CD4. This trend toward thicker RNFL among subjects with lower nadir CD4 cell counts persisted at the time of follow up OCT where participants with nadir CD4howed average RNFL thickness in the superior and temporal quadrants of 117.9±18.3 μm and 63.8±12.8 μm, respectively, compared to a superior thickness of 110.5±16.9 μm(P=0.034) and temporal thickness of 57.3±11.6 μm(P=0.007) among those with higher nadir CD4. CONCLUSION: Patients with lower nadir CD4 cell counts have thicker RNFL in the superior and temporal quadrants compared to those with higher nadir CD4 counts. RNFL thickness in hIV positive patients may be affected by historic hIV disease control and should be considered when evaluating hIV positive patients for glaucoma.

关键词： glaucoma glaucoma suspect human immunodeficiency virus retinal nerve fiber layer

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Lip rejuvenation and filler complications in the perioral region

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Plastic and Aesthetic Research 2022年第1期9卷 413-419页

作者： elizabeth h.Wick Erin Ostby Lisa D.Grunebaum Department of Otolaryngology-head and Neck Surgery University of MiamiMiamiFL 33136USA Department of Surgery Division of Otolaryngology-Head and Neck SurgeryUniversity of VermontBurlingtonVT 05401USA

Lip and perioral augmentation procedures have become increasingly popular over the last two decades due to cultural trends,emphasizing youth and *** understanding of lip anatomy and aesthetics has traditionally formed the basis for successful ***,as new technology becomes available,patient standards have increased,requiring an intricate understanding of filler properties and the advantages of different technical *** chapter touches on pertinent anatomy and aesthetics of perioral *** also provides an overview of the properties of the fillers currently available in the United States marketplace for perioral *** technique and materials currently favored by the senior author are described in greater ***,the chapter will overview potential complications and recommended management.

关键词： hyaluronic acid filler lip augmentation perioral augmentation rheology

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A Unifi ed Geometric Rule for Designing Nanomagnetism in Graphene

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Nano Research 2008年第6期1卷 497-501页

作者： Decai Yu elizabeth M.Lupton h.J.Gao Chao Zhang Feng Liu Department of Materials Science and Engineering University of UtahSalt Lake CityUT 84112USA Institute of Physics Chinese Academy of ScienceBeijing 100080China School of Engineering Physics University of WollongongNSW 2522Australia

Based on the underlying graphene lattice symmetry and an itinerant magnetism model on a bipartite lattice,we propose a unifi ed geometric rule for designing graphene-based magnetic nanostructures:spins are parallel(ferromagnetic(FM))on all zigzag edges which are at angles of 0°and 120°to each other,and antiparallel(antiferromagnetic(AF))at angles of 60°and 180°.The rule is found to be consistent with all the systems that have been studied so *** the rule,we predict several novel graphene-based magnetic nanostructures:0-D FM nanodots with the highest possible magnetic moments,1-D FM nanoribbons,and 2-D magnetic superlattices.

关键词： Nanomagnetism graphene-based nanostructures magnetic ordering

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Soybean Ferritin:Isolation,Characterization,and Free Radical Generation

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Journal of Integrative Plant Biology 2012年第1期54卷 45-54页

作者： Andrea Galatro elizabeth Robello Susana Puntarulo Physical Chemistry-PRALIB School of Pharmacy and BiochemistryUniversity of Buenos Aires

The main aim of this work was to assess the multi-task role of ferritin （Ft） in the oxidative metabolism of soybean （Glycine max）. Soybean seeds incubated for 24 h yielded 41 4- 5μg Ft/g fresh weight. The rate of in vitro incorporation of iron （Fe） into Ft was tested by supplementing the reaction medium with physiological Fe chelators. The control rate, observed in the presence of 100μM Fe, was not significantly different from the values observed in the presence of 100 μM Fe-his. however, it was significantly higher in the presence of 100 μM Fe-citrate （approximately 4.5-fold） or of 100 μM Fe-ATP （approximately 14-fold）. Moreover, a substantial decrease in the Trp-dependent fluorescence of the Ft protein was determined during Fe uptake from Fe-citrate, as compared with the control. On the other hand, Ft addition to homogenates from soybean embryonic axes reduced endogenously generated ascorbyl radical, according to its capacity for Fe uptake. The data presented here suggest that Ft could be involved in the generation of free radicals, such as hydroxyl radical, by Fe-catalyzed reactions. Moreover, the scavenging of these radicals by Ft itself could then lead to protein damage. however, Ft could also prevent cellular damage by the uptake of catalytically active Fe.

关键词： ferritin free radical iron soybean.

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A systematic review of patient reported outcome measures (PROMs) and quality of life reporting in patients undergoing laparoscopic cholecystectomy

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hepatobiliary Surgery and Nutrition 2019年第3期8卷 228-245页

作者： Prita Daliya elizabeth h.Gemmill Dileep N.Lobo Simon L.Parsons Gastrointestinal Surgery Nottingham Digestive Diseases Centre and National Institute for Health Research(NIHR)Nottingham Biomedical Research CentreNottingham University Hospitals NHS Trust and University of NottinghamQueen’s Medical CentreNottingham NG72UHUK Department of General Surgery Sherwood Forest Hospitals NHS TrustKing’s Mill HospitalSutton-in-Ashfield NG174JLUK MRC/ARUK Centre for Musculoskeletal Ageing Research School of Life SciencesUniversity of NottinghamQueen’s Medical CentreNottingham NG72UKUK Trent Oesophago-Gastric Unit City Hospital CampusNottingham University Hospitals NHS TrustNottingham NG51PBUK

Patient reported outcome measures(PROMs)provide a valuable means of measuring outcomes subjectively from a patient's perspective,facilitating the assessment of service quality across healthcare providers,and assisting patients and clinicians in shared decision *** primary aim of this systematic review was to critically appraise all historic studies evaluating patient reported quality of life,in adult patients undergoing laparoscopic cholecystectomy for symptomatic *** secondary aim was to perform a quality assessment of cholecystectomy-specific PROM-validation studies.A literature review was performed in PubMed,Google ScholarTM,the Cochrane Library,Medline,CINAhL,EMBASE and PsychINFO databases up to September *** characteristics,PROM-specific details and a bias assessment were summarised for non-validation studies.A COnsensus-based Standards for the selection of health Measurement INstruments(COSMIN)analysis was performed to assess the methodological quality of identified PROM-validation *** one studies were found to evaluate health-related quality of life(hRQoL)after laparoscopic *** 94.1%of these studies included PROMs as a primary outcome measure,hrough randomised controlled trials(RCTs).There was significant variation in the selection and reporting of PROMs,with no studies declaring patient involvement in PROM selection,and 88.2%of studies failing to document the management of missing data points,or non-returned surveys(33.3%).In the 6 PROM-validation studies identified,only 5 psychometric properties were evaluated,the findings of which were limited due to the small number of *** systematic review identifies a lack in consistency of study design and PRO reporting in clinical *** an increasing number of studies are being performed to evaluate PROs,a lack of adherence to existing PRO administration and reporting guidelines is continuing to negatively affect st

关键词： Cholecystectomy patient reported outcomes(PROs) patient reported outcome measures(PROMs) quality of life(QoL) COnsensus-based Standards for the selection of health Measurement INstruments(COSMIN)

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Role of hepatitis B virus in development of hepatocellular carcinoma:Focus on covalently closed circular DNA

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World Journal of hepatology 2022年第5期14卷 866-884页

作者： Claryssa Bianca elizabeth Sidhartha Claudio Tiribelli Korri Elvanita El-Khobar Caecilia h C Sukowati Department of Biomedicine Indonesia International Institute for Life SciencesJakarta 13210Indonesia Centro Studi Fegato Fondazione Italiana Fegato ONLUSTrieste 34149Italy Eijkman Center for Molecular Biology National Research and Innovation Agency(BRIN)Jakarta 10340Indonesia

Chronic infection with hepatitis B virus(hBV)remains a major global health problem,especially in developing *** may lead to prolonged liver damage,fibrosis,cirrhosis,and hepatocellular *** chronic hBV infection is related to host immune response and the stability of the covalently closed circular DNA(cccDNA)in human *** addition to being essential for viral transcription and replication,cccDNA is also suspected to play a role in persistent hBV infections or hepatitis relapses since cccDNA is very stable in non-dividing human *** the pathogenicity and oncogenicity of hBV components would be essential in the development of new diagnostic tools and treatment *** review summarizes the role and molecular mechanisms of hBV cccDNA in hepatocyte transformation and hepatocarcinogenesis and current efforts to its detection and targeting.

关键词： hepatitis B virus Covalently closed circular DNA hepatocellular carcinoma hepatocarcinogenesis

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