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The influence of canopy-layer composition on understory plant diversity in southern temperate forests

Forest Ecosystems 2017年第2期4卷 154-166页

作者： Luciana Mestre Monica Toro-Manriquez Rosina Soler Alejandro Huertas-herrera Guillermo Martinez-Pastur Maria Vanessa Lencinas National Scientific and Technical Research Council (CONICET) Austral Center for Scientific Research (CADIC-CONICET) Houssay 200 9410 Ushuaia Tierradel Fuego Argentina

Background： Understory plants represents the largest component of biodiversity in most forest ecosystems and plays a key role in forest *** their importance, the influence of overstory-layer composition on understory plant diversity is relatively poorly understood within deciduous-evergreen broadleaved mixed *** aim of this work was to evaluate how tree overstory-layer composition influences on understory-layer diversity in three forest types（monospecific deciduous Nothofagus pumilio（Np）, monospecific evergreen Nothofagus betuloides（Nb）, and mixed ***（M） forests）, comparing also between two geographical locations（coast and mountain） to estimate differences at landscape ***： We recorded 46 plant species： 4 ferns, 12 monocots, and 30 ***-layer composition influences the herb-layer structure and diversity in two different ways： while mixed forests have greater similarity to evergreen forests in the understory structural features, deciduous and mixed were similar in terms of the specific composition of plant *** pure stands were the most diverse, meanwhile evergreen stands were least *** of exclusive species of mixed forest could represent a transition where evergreen and deciduous communities meet and ***, landscape has a major influence on the structure, diversity and richness of understory vegetation of pure and mixed forests likely associated to the magnitude and frequency of natural disturbances, where mountain forest not only had highest herb-layer diversity but also more exclusive ***： Our study suggests that mixed Nothofagus forest supports coexistence of both pure deciduous and pure evergreen understory plant species and different assemblages in coastal and mountain *** the mixture of canopy patch types within mixed stands will be important for conserving the natural patterns of understory plant composition in southern beech mixe

关键词： Landscape Understory communities Understory structure Forest structure Nothofagus Conservation

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Fragmentation patterns and systematic transitions of the forested landscape in the upper Amazon region, Ecuador 1990-2008

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Journal of Forestry Research 2014年第2期25卷 301-309页

作者： Santiago Bonilla-Bedoya Juan R.Molina José E.Macedo-Pezzopane Miguel A.herrera-Machuca DepartaTento de Ingeniería Forestal E.T.S.I.A.M.Universidad de CórdobaCaTpus de Excelencia Internacional Agroali Tentario (ceiA3) Secretaria Nacional de Educación Superior CienciaTecnología e Innovación del EcuadorWhy Tper E7-37 y Alpallana Quito. Ecuador Departa Tento de Engenharia Florestal Universidade Federal do Espírito Santo

The analysis of the systematic transitions in the forested landscape and the study of the forest fragmentation patterns allow us to deepen our understanding of the changes in the vegetation ground cover. The importance of knowing the intricate patterns of the land usage of the upper basin of the Amazon region is widely recognized. This zone is one of the most diverse biological areas in the world, is home to large areas of mature tropical cloud forest and demonstrates high probabilities of stable climatic conditions in light of global warming. The research quan- tiffed systematic transitions through the ＂loss＂ and ＂gain＂ of the different categories of landscape during the eighteen-year study period of the Ecuadorian Amazon Region （EAR）, the forest fragmentation patterns were also analyzed based on a set of indicators. Therefore, with respect to the entirety of the landscape, the results registered for the ground coverage in forested areas during the first period （1990-2000）, show a decrease of 6.99% and an increase of 0.68%; and during the second period （2000-2008）, show a decrease of 3.99% and an increase of 2.14%. It demonstrated that forest and agricultural areas tended to replace or be replaced by herbaceous vegetation faster than expected fortuitously. Finally, the indices of fragmentation signaled intense changes during the 1990-2000 period with a reduction during the period 2000-2008. Per- centages registered in the Largest Patch Index （LPI） were between 79.58%; 52.39% and 49.99% respectively; while the Patch Density （PD） varied between 0.04; 0.06 and 0.07. This suggests the propensity of for- est cover to remain intact. The results of this investigation suggest a tendency towards stability in Ecuador＇s Amazon landscape. Within the framework for development and management of this area, the tendency is natural regeneration. This permits a consolidation of the conservation, reforestation, forestation and agricultural forestry plans, programs and systems for the

关键词： Ecuadorian Amazon systematic transitions fragmentation natural regeneration

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Exploring alternative treatments for Helicobacter pylori infection

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World Journal of Gastroenterology 2014年第6期20卷 1450-1469页

作者： Guadalupe Ayala Wendy Itzel Escobedo-Hinojosa Carlos Felipe de la Cruz-herrera Irma Romero Centro de Investigación sobre Enfermedades Infecciosas Instituto Nacional de Salud Pública INSP Departamen-to de Bioquímica Facultad de Medicina Universidad Nacional Autónoma de México

Helicobacter pylori(H. pylori) is a successful pathogen that can persist in the stomach of an infected person for their entire life. It provokes chronic gastric inflammation that leads to the development of serious gastric diseases such as peptic ulcers, gastric cancer and Mucosa associated lymphoid tissue lymphoma. It is known that these ailments can be avoided if the infection by the bacteria can be prevented or eradicated. Currently, numerous antibiotic-based therapies are available. However, these therapies have several inherent problems, including the appearance of resistance to the antibiotics used and associated adverse effects, the risk of re-infection and the high cost of antibiotic therapy. The delay in developing a vaccine to prevent or eradicate the infection has furthered research into new therapeutic approaches. This review summarises the most relevant recent studies on vaccine development and new treatments using natural resources such as plants, probiotics and nutraceuticals. In addition, novel alternatives based on microorganisms, peptides, polysaccharides, and intragastric violet light irradiation are presented. Alternative therapies have not been effective in eradicating the bacteria but have been shown to maintain low bacterial levels. Nevertheless, some of them are useful in preventing the adverse effects of antibiotics, modulating the immune response, gastroprotection, and the general promotion of health. Therefore, those agents can be used as adjuvants of allopathic anti-H. pylori eradication therapy.

关键词： Helicobacter pylori Treatment Natural products Probiotics Nutraceuticals

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Forage offering and seasonal intake comparisons to evaluate European rabbit threat in Nothofagus forests of southern Patagonia

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Ecological Processes 2022年第1期11卷 604-617页

作者： Alejandro Huertas herrera Mónica Toro‑Manríquez Laura Borrelli María Vanessa Lencinas Guillermo Martínez Pastur Centro de Investigación en Ecosistemas de la Patagonia(CIEP) Camino Baguales s/n Km 4CoyhaiqueChile Ulterarius Consultores Ambientales y Científicos Ltda. Ignacio Serrano 420CoyhaiqueChile Instituto Nacional de Tecnología Agropecuaria(INTA) EEA BarilocheModesta Victoria 44508400 San Carlos de BarilocheRío NegroArgentina Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas(CADIC)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 2009410 UshuaiaTierra del FuegoArgentina.

Background:The European rabbit(Oryctolagus cuniculus L.1758)was introduced into different regions of the world,generating significant trade‑offs that critically impacted native ***,we evaluate the rabbit’s forage intakes in three vegetation types(forests,shrublands,and grasslands)along the four seasons in a temperate forest landscape in Southern Patagonia and discuss the potential threats over native *** formulated the following questions:(i)what is the forage offer at each vegetation type?(ii)what is the rabbit’s forage intake and how it varied across the seasons along the year?and(iii)which vegetation types and plant life forms were more used according to the rabbit’s forage intakes?Methods:We censused understory vegetation to characterize the forage offer at each vegetation type and determined seasonal dietary intakes using microhistological analysis of *** plant species identified in the field were grouped according to life form classes(tree regeneration,shrubs,forbs,graminoids,orchids,ferns,bryophytes,and hemiparasites).Data were analysed through uni‑and multi‑variate analyses,determining relationships between forage offer and the rabbit’s forage ***:Forage intakes revealed changes in plant life form consumption across vegetation types,where intake pressure was considerably different for tree regeneration(p=0.001),graminoids(p=0.001),and hemiparasites(p=0.001).Besides,significant changes in consumption among seasons were detected for shrubs(p=0.001),ferns(p=0.030),and hemiparasites(p=0.002).Although many species play an important role in the rabbit’s forage intake networks(e.g.,Chiliotrichum diffusum,Holcus lanatus),the strongest intake linkages were found in exotic grasses(e.g.,Poa pratensis and Festuca sp.),native hemiparasites(e.g.,Misodendrum sp.),native shrubs(e.g.,Empetrum rubrum),and native trees(e.g.,Nothofagus sp.).The summer and autumn seasons presented higher intake compared to the winter and spring seasons.F

关键词： Forest ecology Oryctolagus cuniculus Plant-animal interaction Vegetation type Herbivory Habitat use

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Risk factors for major gastrointestinal bleeding in the general population in Finland

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World Journal of Gastroenterology 2022年第18期28卷 2008-2020页

作者： Pareen Vora Ronald herrera Arto Pietila Ulrich Mansmann Gunnar Brobert Markku Peltonen Veikko Salomaa Integrated Evidence Generation Bayer AGBerlin 13353Germany Institute for Medical Information Processing Biometryand EpidemiologyLudwig Maximilians UniversitätMunich 81337Germany Pettenkofer School of Public Health Ludwig Maximilians UniversitätMunich 81337Germany Department of Public Health and Welfare National Institute for Health and Welfare(THL)Helsinki FI-00271Finland Medical Affairs Bayer ABSolna 17165Sweden

BACKGROUND Data on non-drug related risk-factors for gastrointestinal bleeding(GIB)in the general population are limited,especially for life-style factors,clinical measurements and laboratory *** To identify and investigate non-drug risk factors for major GIB in the general population of *** We performed a retrospective cohort study using data from the FINRISK health examination surveys,which have been conducted every 5 years across Finland from 1987 to *** were adults aged 25 years to 74 years,excluding those with a previous hospitalization for ***-up from enrollment was performed through linkage to national electronic health registers and ended at an event of GIB that led to hospitalization/death,death due to any other cause,or after 10 *** included demographics,socioeconomic and lifestyle factors,clinical measurements,laboratory parameters and *** selection was undertaken using Least Absolute Shrinkage and Selection Operator(LASSO)and factors associated with GIB were identified using Cox *** Among 33,508 participants,403(1.2%)experienced GIB[256 men(63.5%);mean age,56.0 years(standard deviation(SD)±12.1)]and 33105 who did not experience GIB[15768 men(47.6%);mean age,46.8(SD±13)years],within 10 years of *** associated with a significantly increased risk of GIB were baseline age[per 10-year increase;hazard ratio(HR)1.62,95%confidence interval(CI):1.42-1.86],unemployment(HR:1.70,95%CI:1.11-2.59),body mass index(BMI)(HR:1.15,95%CI:1.01-1.32),gamma-glutamyl transferase(GGT)(HR:1.05,95%CI:1.02-1.09),precursors of GIB(HR:1.90,95%CI:1.37-2.63),cancer(HR:1.47,95%CI:1.10-1.97),psychiatric disorders(HR:1.32,95%CI:1.01-1.71),heart failure(HR:1.46,95%CI:1.04-2.05),and liver disorders(HR:3.20,95%CI:2.06-4.97).Factors associated with a significantly decreased risk of GIB were systolic blood pressure(SBP)(HR:0.78,95%CI:0.64-0.96),6-10 cups of coffee a day(HR:0.67,95%CI:0.46-0

关键词： Risk factors Gastrointestinal hemorrhage General population Finland Life style Population health

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Magnetic lattices for ultracold atoms and degenerate quantum gases

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Science Bulletin 2016年第14期61卷 1097-1106页

作者： Yibo Wang Prince Surendran Smitha Jose Tien Tran Ivan herrera Shannon Whitlock Russell Mc Lean Andrei Sidorov Peter Hannaford Centre for Quantum and Optical Science Swinburne University of Technology Dodd-Walls Centre for Photonic and Quantum Technologies Department of Physics University of Auckland Physikalisches Institut Universitt Heidelberg

We review recent developments in the use of magnetic lattices as a complementary tool to optical lattices for trapping periodic arrays of ultracold atoms and degenerate quantum gases. Recent advances include the realisation of Bose–Einstein condensation in multiple sites of a magnetic lattice of one-dimensional microtraps, the trapping of ultracold atoms in square and triangular magnetic lattices,and the fabrication of magnetic lattice structures with submicron period suitable for quantum tunnelling ***, we describe a proposal to utilise long-range interacting Rydberg atoms in a large spacing magnetic lattice to create interactions between atoms on neighbouring sites.

关键词： Magnetic lattices Ultracold atoms Degenerate quantum gases - Quantum simulation

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Small-signal Model for Dual-active-bridge Converter Considering Total Elimination of Reactive Current

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 450-458页

作者： Juan Ramon Rodriguez-Rodriguez Nadia Maria Salgado-herrera Jacinto Torres-Jimenez Nestor Gonzalez-Cabrera David Granados-Lieberman Martin Valtierra-Rodriguez the Universidad Nacional Autonoma de Mexico Facultad de IngenieriaDepto.Energia Electri-ca.Av.Universidad 3000Col.UNAM CUCoyoacanCDMXMexico the Instituto de Energias Renovables Universidad Nacional Autonoma de MexicoPriv.Xochicalco s/nCol.Centro.TemixcoMorelosMexico the Instituto Tec-nologico Superior de Irapuato Carretera Irapuato-Silao km 12.5.IrapuatoGuanajuatoMexico the Universidad Autonoma de Queretaro Campus San Juan del RioRio Moctezuma 249San Juan del RioQueretaroMexico

Emerging technologies such as electric vehicles,solid-state transformers,and DC transformers are implemented using the closed-loop bi-directional dual-active-bridge(DAB)*** this context,it is necessary to have average models that provide an efficient way of tuning the proportional integral(PI)compensator parameters for large-and small-signal *** present a novel small-signal model(SSM)for DAB converter with a single closed-loop PI controller and the total elimination of reactive current(IQ=0).The method applies a modulation technique for IQ=0 and introduces a composite function in the controller while reducing the original nonlinear switching model,which allows to decrease the order of the transfer function and analyze the closed-loop *** proposed SSM is analyzed using different response time,load,and DC voltage *** simulation and experimental results demonstrate the ease of implementation and effectiveness of the proposed model with respect to other SSM techniques.

关键词： Small-signal model(SSM) dual-active-bridge(DAB)converter reactive current elimination proportional integral(PI)control

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Sex differences in Alzheimer's disease:an urgent research venue to follow

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Neural Regeneration Research 2024年第12期19卷 2569-2570页

作者： Raquel Jiménez-herrera Ana Contreras Juan D.Navarro-López Lydia Jiménez-Díaz Neurophysiology&Behavior Lab University of Castilla-La ManchaSchool of Medicine of Ciudad RealCiudad RealSpain

Due to increasing life expectancy,the amount of people with dementia worldwide is expected to experience a substantial rise,with estimates indicating a growth from 55 million in 2019 to a staggering 139 million by the... 详细信息

关键词： Alzheimer predominant estimates

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Study and ICH validation of a reverse-phase liquid chromatographic method for the quantification of the intact monoclonal antibody cetuximab

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Journal of Pharmaceutical Analysis 2016年第2期6卷 117-124页

作者： Antonio Martinez-Ortega Agustin herrera Antonio Salmeron-Garcia Jose Cabeza Luis Cuadros-Rodriguez Natalia Navas Department of Analytical Chemistry University of Granada Faculty of Science Campus Fuentenueva s/n E-18071 Granada Spain UGC intercentro Interniveles Farmacia Granada San Cecilio Hospital Biomedical Research Institute ibs. GRANADA. Hospitales Universitarios de Granada University of Granada E-18012 Granada Spain Department of Analytical Chemistry Science Faculty Biomedical Research Institute ibis. GRANADA University of Granada Campus Fuentenuevo s/n E-18071 Granada Spain

Cetuximab （CTX） is a potent chimeric mouse/human monoclonal antibody （mAb） approved worldwide for treatment of metastatic colorectal cancer. Among the various biological and physical analyses per- formed for full study on this biopharmaceutic, the determination of the concentration preparations throughout manufacturing and subsequent handling in hospital is particularly relevant. In the present work, the study and validation of a method for quantifying intact CTX by reverse-phase high-perfor- mance liquid chromatography with diode array detection （（RP）HPLC/DAD） is presented. With that end, we checked the performance of a chromatographic method for quantifying CTX and conducted a study to validate the method as stability-indicating in accordance with the International Conference on Harmo- nization guidelines （ICH） for biotechnological drugs; therefore, we evaluated linearity, accuracy, preci- sion, detection and quantification limits, robustness and system suitability. The specificity of the method and the robustness of the mAb formulation against external stress factors were estimated by compre- hensive chromatographic analysis by subjecting CTX to several informative stress conditions. As de- monstrated, the method is rapid, accurate, and reproducible for CTX quantification. It was also suc- cessfully used to quantify CTX in a long-term stability study performed under hospital conditions.

关键词： Reverse-phase high performance liquidchromatography Diode detector Stress study Biopharmaceuticals Cetuximab

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An Invasive Succulent Plant (Kalanchoe daigremontiana) Influences Soil Carbon and Nitrogen Mineralization in a Neotropical Semiarid Zone

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Pedosphere 2018年第4期28卷 632-643页

作者： Ileana herrera Jose R. FERRER-PARIS Diana BENZO Saul FLORES Belkis GARCIA Jafet M. NASSAR Ecuela de Ciencias Ambientales Universidad Espiritu Santo Guayaquil 091650 (Ecuador) Centro de Ecologla Instituto Venezolano de Investigaciones Cientificas (IVIC) Caracas 1020 (Venezuela) Centro de Estudios Botdnieos y Agroforestales Instituto Venezolano de Investigaeiones Cientificas Maracaibo 4005 (Venezuela)

It has long been recognized that plant invasions may alter carbon （C） and nitrogen （N） cycles, but the direction and magnitude of such alterations have been rarely quantified. In this study, we quantified the effects caused by the invasion of a noxious exotic plant, Kalanchoe daigrernontiana （Crassulaceae）, on C and N mineralization and enzymatic and microbial activities in the soil of a semiarid locality in Venezuela. We compared soil parameters associated with these processes （C and N mineralization time and the cumulative values, fluorescein diacetate hydrolytic activity, and activities of dehydrogenase, β-glucosidase, glucosaminidase, and urease） between invaded and adjacent non-invaded sites. In addition, correlations among these parameters and the soil physical-chemical properties were also examined to determine if a positive feedback exists between nutrient availability and K. daigremontiana invasion. Overall, our results showed that C mineralization and transformation of organic compounds to NH4^＋ were favored at sites colonized by K. daigrernontiana. With this species, we found the highest cumulative amounts of NH4^＋-N and C and the lowest mineralization time. These results could be explained by higher activities of urease and glueosaminidase in soils under the influence of K. daigremontiana. In addition, higher amounts of organic matter and moisture content in invaded soils might favor C and N mineralization. In conclusion, invasion of Neotropical semiarid zones by K. daigrernontiana may influence the chemical and biological properties of the soils covered by this species, increasing nutrient bioavailability, which, in time, can facilitate the invasion process.

关键词： Akaike Information Criterion C and N pools enzymatic activity NH4^+-N NO3^--N nutrient availability plant invasion

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