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Effects of the allelopathic plant Artemisia herba-alba Asso on the soil seed bank of a semi-arid plant community

Journal of Plant Ecology 2017年第6期10卷 927-936页

作者： Antonio I.Arroyo yolanda Pueyo Ramón Reiné Maria Luz Giner Concepción L.Alados Instituto Pirenaico de Ecología(CSIC) Av.Montañana 1005P.O.Box 13.034Zaragoza 50080Spain Escuela Politécnica Superior(Universidad de Zaragoza) Ctra.Cuarte s/nHuesca 22071Spain

Aims Seed bank strongly influences composition and structure of above-ground *** attention has been paid to the role of allel-opathy driving soil seed bank dynamics,even though allelochemicals released by allelopathic plants might determine whether a species can or cannot germinate from the soil seed bank and,therefore,to co-exist in the neighborhood of the allelopathic ***,the effects of allelopathic plants on community organization through the effects of allelochemicals on soil seed bank remain largely *** this study,we assessed spatial heterogeneities in soil seed bank caused by the presence of allelopathic plants,and evaluated allelo-pathic effects on seed bank germination and seedling *** We examined the effects of the allelopathic shrub Artemisia herba-alba Asso on the spatial structure(in terms of species richness and seed density)of the soil seed bank of a semi-arid ecosystem in NE ***,we evaluated seed bank richness and density at three microsites:under the canopy of ***-alba individuals,under the canopy of Salsola vermiculata L.(a non-allelopathic shrub)individuals,and in bare *** addition,we assessed the effects of aqueous extract of ***-alba on soil seed bank germination(seed-ling emergence and emergence timing)and seedling *** Findings We found that seed bank richness and density were higher under shrub canopy than they were in bare ***-alba and *** microsites had similar seed bank ***,seed bank density was higher under ***-alba because of the high abundance of ***-alba *** extract reduced seedling emergence from the seed bank by 50%,and affected mortality of some emerged *** the other hand,aqueous extract did not influence the emergence timing of *** conclude that,although the presence of allelo-pathic plants does not cause relevant changes in seed bank struc-ture relative to similar non-allelopathi

关键词： allelopathic shrub aqueous extract Middle Ebro Valley seed bank inhibition seed bank density seedling emergence

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Aggregate Consumption： An Analysis by Numeric Simulation

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Chinese Business Review 2017年第8期16卷 403-413页

作者： Ricardo Luis chaves Feij6 University of Sao Paulo Ribeirao Preto Brazil

It is estimated that the aggregate consumption behavior of families by computational procedures in an abstract model contemplates the maximization of agent utility in each period （two dates）, the attendance of budgetary restrictions and the conditions of general equilibrium （without production）. It uses the technique of selection of candidate points in a simulation process with a portfolio of efficient assets and a hypothesis for the process of determining the returns of the securities： A GARCH process. By this technique, it compares the stochastic volatility patterns between the artificial series, obtained in the simulation, and the real series of household aggregate consumption in the US and Brazil.

关键词： aggregate consumption numeric simulation general equilibrium stochastic process

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Gastrointestinal tuberculosis:An autopsy-based study

Infectious Medicine

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Infectious Medicine 2023年第2期2卷 122-127页

作者： Julio Cesar Mantilla Juan Joséchaves Ferney Africano-Lopez Néstor Blanco-Barrera Marta Juliana Mantilla Department of Pathology Universidad Industrial de SantanderBucaramanga 680002Colombia Department of Pathology Hospital Universitario de SantanderBucaramanga 680002Colombia Department of Pathology Fundación Universitaria de Ciencias de la SaludBogotá111411Colombia Department of Gastroenterology Gastrocenter and Medical SpecialitiesIpiales 524061Colombia Department of Gastroenterology Universidad Militar Nueva GranadaBogotá250240Colombia Department of Rheumatology Universidad de la SabanaChía 250001Colombia

Background:Tuberculosis is a disease of great relevance since it is one of the leading causes of morbidity and mortality *** tuberculosis is an unusual *** is defined as the involvement of any segment of the digestive tract,associated viscera,and *** study’s main objective is to collect information from autopsies of patients diagnosed with gastrointestinal tuberculosis in a Pathology reference center in ***:This is a retrospective and descriptive study of autopsy reports.A total of 4,500 autopsies were performed between January 2004 and December *** inclusion criteria were authorization of a family member following local law regulations and a final autopsy diagnosis of gastrointestinal tuberculosis using microscopic ***:Forty-eight patients with gastrointestinal tuberculosis autopsies were included in our *** of the patients were male(n=35,72.9%)with a median age of 40.5 years *** immunodeficiency virus infection history was reported in 28 cases(58.33%).The most affected gastrointestinal tract site was the terminal *** and thickened epithelium were common autopsies macroscopic *** multiorgan compromise was a relevant finding in patients with gastrointestinal ***:Gastrointestinal tuberculosis is a disease of great importance,being its diagnosis a clinical *** can be reported in a high percentage of cases,so autopsy diagnosis can help reveal more accurate data about this condition.

关键词： Gastrointestinal tuberculosis Autopsy Forensic pathology Infections Colombia

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Collaborative Virtual Learning in Education in STEM Education

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Management Studies 2020年第4期8卷 315-324页

作者： yolanda Mpu E.O.Adu University of Fort Hare AliceSouth Africa

There has been a recent explosion of interest from academics across a wide range of disciplines in the use of Multi-User Virtual Environments for education,driven by the success of platforms such as Internet Communication Technology learning skills in higher *** digital virtual worlds are used in the 21st century learning,advances in the capabilities and the spread of technology have fed a recent boom in interest in massively multi-user 3D virtual worlds for entertainment,and this in turn has led to a surge of interest in their educational *** these platforms are used more often as environments for teaching and learning,there is increased need to integrate them with other institutional systems,Web-based Virtual Learning Environments(VLE)in *** this paper,we briefly review the use of virtual worlds for education,from informal learning to formal instruction,and consider what is required to turn a virtual world from a Multi-User Virtual Environment into a fully fledged 3D Virtual Learning Environment(VLE).In this we focus on the development of Moodle—a system which integrates the popular 3D virtual world of Second Life with the open-source Virtual Learning Environment.

关键词： Multi-User Virtual Environments 3D Virtual Learning Environments moodle second life digital virtual worlds internet communication technology

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Did maize domestication and early spread mediate the population genetics of corn leafhopper?

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Insect Science 2019年第3期26卷 569-586页

作者： Julio S. Bernal Amanda M. Davila-Flores Raul F. Medina yolanda H. Chen Kyle E. Harrison Kimberly A. Berrier Department of Entomology Texas A&M University College Station Texas USA Department of Plant and Soil Sciences University of Vermont Burlington Vermont USA

Investigating how crop domestication and early farming mediated crop attributes, distributions, and interactions with antagonists may shed light on today's agricultural pest problems. Crop domestication generally involved artificial selection for traits desirable to early farmers, for example, in creased productivity or yield, and enhanced qualities, though invariably it altered the interactions between crops and insects, and expanded the geographical ranges of crops. Thus, some studies suggest that with crop domestication and spread, insect populations on wild crop ancestors gave rise to pestiferous insect populations on crops. Here, we addressed whether the emergence of corn leafhopper (Dalbulus ma id is) as an agricultural pest may be associated with domestication and early spread of maize (Zea mays mays). We used AFLP markers and mitochondrial COI sequences to assess population genetic structuring and haplotype relationships among corn leafhopper samples from maize and its wild relative Zea diploperennis from multiple locations in Mexico and Argentina. We uncovered seven corn leafhopper haplotypes contained within two haplogroups, one haplogroup containing haplotypes associated with maize and the other containing haplotypes associated with Z. diploperennis in a mountainous habitat. Within the first haplogroup, one haplotype was predominant across Mexican locations, and another across Argentinean locations;both were considered pestiferous. We suggested that the divergence times of the maize-associated haplogroup and of the "pestiferous" haplotypes are correlated with the chronology of maize spread following its domestication. Overall, our results support a hypothesis positing that maize domestication favored corn leafhopper genotypes preadapted for exploiting maize so that they became pestiferous, and that with the geographical expansi on of maize farming, corn leafhopper colonized Z. diploperennis, a host exclusive to secluded habitats that serves as a refuge fo

关键词： Dalbulus maidis haplotype network analysis perennial teosinte population genetic structuring Zea diploperennis Zea mays mays

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Protective Green Patinas on Copper in Outdoor Constructions

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Journal of Environmental Protection 2011年第7期2卷 956-959页

作者： yolanda Hedberg Inger Odnevall Wallinder 不详

The last 15 years of research related to atmospheric corrosion and the release of copper to the environment are shortly summarized. Brown and green patinas with high barrier properties for corrosion are gradually evolved on copper at atmospheric conditions. The corrosion process and repeated dry and wet cycles results in a partial dissolution of corrosion products within the patina. Dissolved copper can be released and dispersed into the environment via the action of rainwater, however the major part is rearranged within the patina during drying cycles. The majority of corrosion products formed have a poor solubility, very different from water soluble copper salts. The release process is very slow and takes place independent of patina color. Its extent has only a marginal effect on the adherent patina. Released copper rapidly interacts with organic matter and in contact with different surfaces already in the close vicinity of the building, such as drainage systems, storm water pipes, pavements, stone materials and soil systems. These surfaces all have high capacities to retain copper in the runoff water and to reduce its concentration and chemical form to non-available and non-toxic levels for aquatic organisms.

关键词： Copper Runoff Patina

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Robust hybrid bismuth perovskites as potential photocatalysts for overall water splitting

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Nano Research 2024年第5期17卷 4593-4601页

作者： Antonio J.Chacón-García Herme G.Baldovi Artem A.Babaryk Antonio Rodríguez-Diéguez Sergio Navalón yolanda Pérez Hermenegildo García Patricia Horcajada Advanced Porous Materials Unit IMDEA Energy InstituteAvda.Ramón y Cajal 328935 MóstolesMadridSpain Departamento de Química Universitat Politècnica de València46022 ValènciaSpain Departamento Química Inorgánica Universidad de Granada1807GranadaSpain Departamento de Biología y Geología Física y Química Inorgánica.ESCET.Universidad Rey Juan Carlos28933 MóstolesMadridSpain Instituto de tecnología química CSIC-UPV Universitat Politècnica de València(UPV)46022Spain

Organic-inorganic hybrid perovskites have gained great attention as promising photocatalysts for hydrogen ***,due to their poor stability in water,the use of aqueous hydrohalic acid solutions is specifically required for an efficient hydrogen ***,three novel photoactive lead-free hybrid perovskites based on bismuth and triazolium cations(denoted as IEF-15,IEF-16,and IEF-17(IEF stands for IMDEA energy frameworks))were synthesized and fully characterized(structural,compositional,optical,etc.).Further,these solids were proposed as photocatalysts for the challenging gas phase overall water splitting(OWS)***,IEF-16 thin films exhibited a remarkable photocatalytic activity in both H_(2) and O_(2) evolution,as a consequence of its appropriate bandgap and energy-band alignment,achieving hydrogen evolution rates ofμmol·g_(H_(2))^(-)1846 and 360 after 24 h under ultraviolet-visible(UV-vis)irradiation or simulated solar irradiation,*** study additionally highlights the remarkable structural and photochemical stability of IEF-16 under different operational conditions(*** volume,irradiation and temperature),paving the way for green hydrogen production from OWS using perovskite-based photocatalysts.

关键词： bismuth-based hybrid perovskites thin films photocatalysis overall water splitting green hydrogen

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Pressurized Liquid Extraction of Pigments from Chlamydomonas *** Chemical Characterization by HPLC–MS/MS

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Journal of Analysis and Testing 2018年第2期2卷 149-157页

作者： Lidia Montero Mahshid Sedghi yolanda García Carlos Almeida Carl Safi Nicole Engelen‑Smit Alejandro Cifuentes Jose A.Mendiola Elena Ibáñez Applied Analytical Chemistry University of Duisburg-EssenUniversitaetsstr.545141 EssenGermany Laboratory of Foodomics Bioactivity and Food Analysis DepartmentInstitute of Food Science Research CIAL(CSIC-UAM)Campus de CantoblancoC/Nicolás Cabrera 928049 MadridSpain Spanish Bank of Algae Instituto de Oceanografía y Cambio GlobalFundación Canaria Parque Científico‑TecnológicoUniversidad de Las Palmas de Gran CanariaMuelle de Taliarte s/n35214 Telde(Canary Islands)Spain Wageningen Food and Biobased Research Wageningen University and ResearchPO Box 176700 AA WageningenThe Netherlands

Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae Chlamydomonas *** experimental design is employed to determine the effect of the extraction conditions on the extraction yield and the antioxidant capacity of the different extracts determined using 1,1-diphenyl-2-picryl-hydrazyl and TEAC *** the extracts show significant antioxidant activity in all ***,in this work,the carotenoid and chlorophyll composition of the Chlamydomonas extracts was analyzed by HPLC–DAD–APCI–MS/MS for the first time,being the main compounds lutein and pheophythin a′.

关键词： Antioxidant capacity Chlamydomonas sp. HPLC–DAD–APCI–MS/MS Pigments Pressurized liquid extraction Carotenoids

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Checking procalcitonin suitability for prognosis and antimicrobial therapy monitoring in burn patients

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Burns & Trauma 2018年第1期6卷 39-48页

作者： Luís Cabral Vera Afreixo Rita Meireles Miguel Vaz Catarina chaves Marisa Caetano Luís Almeida JoséArtur Paiva Department of Plastic Surgery and Burns Unit Unidade de QueimadosCoimbra University Hospital Centre(CHUC)Av.Bissaya Barreto s/n3000-075 CoimbraPortugal Autonomous Section of Health Sciences(SACS) University of AveiroAveiroPortugal CIDMA-Center for Research and Development in Mathematics and Applications iBiMEDInstitute for BiomedicineUniversity of AveiroAveiroPortugal Clinical Pathology Department Coimbra University Hospital Centre(CHUC)CoimbraPortugal Pharmacy Department Coimbra University Hospital Centre(CHUC)CoimbraPortugal MedinUP Department of Pharmacology and TherapeuticsFaculty of MedicineUniversity of PortoPortoPortugal Department of Emergency and Intensive Care Medicine Centro Hospitalar Sao JoaoPortoPortugal Faculty of Medicine University of PortoGrupo de Infeccao e SépsisPortoPortugal.

Background: Due to greater infection susceptibility, sepsis is the main cause of death in burn patients. Quick diagnosis and patient stratification, early and appropriated antimicrobial therapy, and focus control are crucial for patients’survival. On the other hand, superfluous extension of therapy is associated with adverse events and arousal of microbial resistance. The use of biomarkers, necessarily coupled with close clinical examination, may predict outcomes, stratifying patients who need more intensive care, and monitor the efficacy of antimicrobial therapy, allowing faster de-escalation or stop, reducing the development of resistance and possibly the financial burden, without increasing mortality. The aim of this work is to check the suitability of procalcitonin (PCT) to fulfill these goals in a large sample of septic burn patients. Methods: One hundred and one patients, with 15% or more of total body surface area (TBSA) burned, admitted from January 2011 to December 2014 at Coimbra Burns Unit (CBU), in Portugal were included in the sample. All patients had a diagnosis of sepsis, according to the American Burn Association (ABA) criteria. The sample was factored by survival (68 survivors and 33 non-survivors). The maximum value of PCT in each day was used for statistical analysis. Data were summarized by location measures (mean, median, minimum, maximum, quartiles) and dispersion measures (standard error and range measures). Statistical analysis was performed with SPSS?23.0 IBM? for Windows?. Results: There were statistically significant differences between PCT levels of patients from the survivor and non-survivor groups during the first and the last weeks of hospitalization as well as during the first week after sepsis suspicion, being slightly higher during this period. During the first 7 days of antimicrobial therapy, PCT was always higher in the non-survivor, still without reaching statistical significance, but when the analysis was extended till the 15th

关键词： Burns Sepsis Procalcitonin Prognosis Antimicrobial stewardship

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Tentative Identification of Phytochemicals and Antioxidant Activities during Fruit-Ripening on Chamaedorea radicalis Mart.

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 361-373页

作者： Gerardo Montelongo-Ruiz yolanda del Rocio Moreno-Ramirez Maria Cruz Juarez-Aragon NohemiNino-Garcia Reyna Ivonne Torres-Acosta Torres-Castillo Jorge Ariel Universidad Autonoma de Tamaulipas Instituto de Ecologia AplicadaCiudad Victoria87019Mexico Universidad Autonoma de Tamaulipas Unidad Academica Multidisciplinaria ManteCiudad Mante89840Mexico

This work aims to determine the phytochemical characterization of the pericarp of Chamaedorea radicalis *** as a non-timber product with potential to obtain phytochemicals with potential applications in the *** from *** were grouped in four ripening stages named as S1,S2,S3 and S4,according to maturity;S1 the most unripe stage and S4 the completely ripe *** of total phenolic compounds,free radical scavenging activities and total flavonoid contents using spectrophotometric methods were ***,the tentative identification of phytochemicals during fruit ripening was done using *** phenolic compound(TPC)content ranged from 7.24 to 12.53 mg gallic acid equivalents per gram of fresh weight(mg GAE/g FW).Total flavonoids(TF)contents ranged from 0.163 to 0.23 mg of quercetin equivalents per g FW(mg QE/g FW).Free radical scavenging activity against DPPH and ABTS radicals varied from 40.80 to 53.68 and from 22.29 to 37.76 mmol Trolox equivalents g FW(mmol TE/g FW),*** assay in vitro by FRAP(ferric reducing antioxidant power)method showed that S3 was the highest level with antioxidant power while S4 was the lowest with Red ripeness stage showed the lowest contents for all *** spectrometry allowed detection of 26 compounds,including phenolics,alkaloids and ***,Kaempferol 3-neohesperidoside and the four saponins identified were present in all ripeness *** phytochemical identification and the spectrophotometric determinations showed that the pericarp of *** presented antioxidants and compounds related to alkaloids,phenolics and *** presence and abundance of each phytochemical regarding each ripeness stage should be considered.

关键词： Metabolite identification palm free radical scavenging phenolic compounds saponins

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