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Variable retention harvesting: conceptual analysis according to different environmental ethics and forest valuation

Ecological Processes 2019年第1期8卷 485-491页

作者： Leonardo Galetto Carolina Torres guillermo J.Martínez Pastur Departamento de Diversidad Biológica y Ecología FCEFyNUniversidad Nacional de Córdoba(UNC)Vélez Sarsfield 16115000 CórdobaArgentina Instituto Multidisciplinario de Biología Vegetal(IMBIV) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Vélez Sarsfield 16115000 CórdobaArgentina Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 2009410 UshuaiaTierra del FuegoArgentina.

Background:Conceptual clarity is important to attain precise communication of scientific knowledge and to implement appropriate technological and policy *** concepts referring to forest management are widely used by decision-makers,regardless of their *** the scientific and methodological issues of forestry practices are frequently discussed in the literature,their normative dimensions are rarely ***,linguistic uncertainty increases when different environmentally ethical perspectives and ways of valuing forests are *** objective was to compare different conceptualizations on the silvicultural systems suggested for forest management and the implications they have for *** have conceptually contrasted highintensity forestry practices with variable retention harvesting,considering different environmentally ethical perspectives and forest valuation ***:Clear boundaries between clear-cutting,selective logging,and variable retention harvesting can be evidenced when different ethical points of view and alternatives in the human-nature relationships are *** have found a variety of definitions of variable retention harvesting that can be analyzed under different ethical *** contrasting views on variable retention harvesting can be evidenced if nature is considered to be purely at human’s service or if it is conceptualized as humans co-inhabiting with *** latter position implies that the maintenance of ecological,evolutionary,and historical processes supported by unmanaged forest stands is a crucial step for forest management proposals based on variable retention ***:Forestry practices that are focused on forest yields and that misinterpret functional uncertainty of forest functioning would be ***,forestry with variable retention harvesting could imply good yields with reasonable conservation management in some contexts,while it could be unacce

关键词： Environmental ethical perspectives Consequentialism Deontological ethics Virtue ethics Policy options for forest and biocultural conservation

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Fracture Response of Reinforced Concrete Deep Beams Finite Element Investigation of Strength and Beam Size

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Applied Mathematics 2013年第11期4卷 1568-1582页

作者： guillermo A. Riveros Vellore Gopalaratnam Department of Civil and Environmental Engineering University of Missouri-Columbia Columbia MO USA Information Technology Laboratory US Army Engineer Research and Development Center Vicksburg MS USA

This article presents a finite element analysis of reinforced concrete deep beams using nonlinear fracture mechanics. The article describes the development of a numerical model that includes several nonlinear processes such as compression and tension softening of concrete, bond slip between concrete and reinforcement, and the yielding of the longitudinal steel reinforcement. The development also incorporates the Delaunay refinement algorithm to create a triangular topology that is then transformed into a quadrilateral mesh by the quad-morphing algorithm. These two techniques allow automatic remeshing using the discrete crack approach. Nonlinear fracture mechanics is incorporated using the fictitious crack model and the principal tensile strength for crack initiation and propagation. The model has been successful in reproducing the load deflections, cracking patterns and size effects observed in experiments of normal and high-strength concrete deep beams with and without stirrup reinforcement.

关键词： Automatic Remeshing Bond Slip Concrete Discrete Crack Finite Element Fracture Mechanics Size Effects Tensile Softening

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Influence of steel jacket thickness on the RC bridges' seismic vulnerability

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第1期6卷 15-34页

作者： Bertha Olmos José Manuel Jara Gerardo Gómez guillermo Martínez Department of Civil Engineering Universidad Michoacana de San Nicolas de Hidalgo

The seismic demands of bridges subjected to strong earthquakes are mostly concentrated on piers. The main objective of this study is to assess the seismic vulnerability of retrofitted bridges with steel jackets. It analyzes the influence of the steel jacket thickness on the seismic capacity and demand of bridges. The bridges in study have two simple supported spans with superstructure composed by AASHTO type girders and a substructure formed with one circular pier over a stiff foundation. They are located on the Pacific coast of Mexico that is a zone of high seismicity. The bridges seismic capacity are evaluated through nonlinear static analyses and the shear force and displacement demands were determined using capacity spectra with a group of 10 real accelerograms from a subduction source. The response spectra were scaled to several peak ground accelerations(PGA) with the aim to estimate four damage scenarios linked each one to a probability of exceedance in a specific period, for return periods in the range of 72-3500 years that represent service level and maximum considered earthquake. Results show that the confining effect provided by the steel jackets substantially improves the seismic performance of the bridges piers. The increase of jacket thickness guides to important increments on columns base shear capacity, and the influence of the steel jacket thickness depends on the limit state and bridge slenderness ratio.

关键词： Steel jacket Piers’retrofit Subduction earthquakes RC piers’vulnerability

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Graphic correlation of Argentine Precordillera and North American Lower/Middle Ordovician sections

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Episodes 2006年第1期29卷 16-19页

作者： Walter C. Sweet guillermo L. Albanesi Department of Geological Sciences The Ohio State University Columbus Ohio 43210 USA CONICET - Museo de Paleontologia Universidad Nacional de Cordoba C. C. 1598 5000 Cordoba Argentina.

Present work demonstrates that a level equivalent to the proposed Whiterockian basal GSSP can be located graphically in a composite section anchored by the Niquivil section of the Argentine Precordillera. The FAD ofCooperignathus aranda in the Niquivil composite section, a candidate for GSSP of the Lower/Middle Ordovician boundary, projects to a level very close to the FAD of Tripodus laevis in the Whiterockian reference section. The conodont-based framework reported here includes the potential for recognition of the proposed Whiterock Canyon-based GSSP, the Cooperignathus aranda-based GSSP, and, possibly, the Baltoniodus triangularisbased GSSP, recently proposed.

关键词：奥陶纪美国相关性阿根廷生物地层学

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Changes in iron transporter divalent metal transporter 1 in proximal jejunum after gastric bypass

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World Journal of Gastroenterology 2014年第21期20卷 6534-6540页

作者： Andrés Marambio guillermo Watkins Fabiola Castro Andrea Riffo Roberta Zú?iga Jaime Jans María E Villanueva guillermo Díaz Department of Surgery University of Chile Clinical HospitalSantiago 8380456Chile Department of Gastroenterology Chilean Air Force Clinical HospitalSantiago 7560171Chile Department of Pharmacological and Toxicological Chemistry University of Chile Chemistry and Pharmacy FacultySantiago 8380492Chile Pathology Service University of Chile Clinical HospitalSantiago 8380456Chile

AIM: To describe the variation that divalent metal transporter 1 (DMT1) shows in patients after Roux-en-Y gastric bypass (RYGB) surgery.

关键词： Roux-en-Y gastric bypass Bariatric surgery Divalent metal transporter 1 Anaemia Iron

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Seed loss before seed predation: experimental evidence of the negative effects of leaf feeding insects on acorn production

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Integrative Zoology 2018年第3期13卷 238-250页

作者： Tara CANELO Álvaro GAYTÁN guillermo GONZÁLEZ-BORNAY Raul BONAL Forest Research Group INDEHESAUniversity of ExtremaduraPlasenciaSpain DITEG Research Group University of Castilla-La ManchaToledoSpain CREAF Cerdanyola del VallèsCataloniaSpain

Insect herbivory decreases plant fitness by constraining plant growth,survival and reproductive *** studies on the effects of herbivory in trees rely on correlational inter-individual comparisons and could,thus,be affected by confounding factors linked to both herbivory and plant *** the Mediterranean Holm oak(Quercus ilex)as a study model,we followed an experimental approach in which leaf-feeding insects(mainly Lepidoptera caterpillars)were excluded from some shoots in all study *** subjected to herbivore exclusion exhibited lower defoliation rates and produced more acorns than control *** constrained shoot growth throughout the study period,but had no effect on the number of female flowers produced per *** production was,however,lower in control shoots due to their higher abortion rates,and also to their greater mortality risk during summer drought,as shoots with fewer leaves were less likely to *** reaction to herbivory inhibits certain physiological pathways involved in plant growth,which,together with the effects of physical damage,reduces the amount and efficiency of the photosynthetic *** increases their vulnerability to environmental stresses,such as water deficit,which limit resource *** is likely a key factor affecting oak regeneration,as it may be a significant source of seed loss prior to pre-dispersal acorn *** experimental studies could help to elucidate its effects in contrasting *** Mediterranean regions,the harsher droughts predicted by climate change models could worsen the effects of insect herbivory on oak reproductive output.

关键词： drought stress insect defoliation oak seed abortion shoot mortality

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Liquid biopsy to detect resistance mutations against anti-epidermal growth factor receptor therapy in metastatic colorectal cancer

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World Journal of Gastrointestinal Oncology 2022年第9期14卷 1654-1664页

作者： guillermo Valenzuela Mauricio Burotto Katherine Marcelain Jaime Gonzalez-Montero Department of Basic and Clinical Oncology University of ChileSantiago 8380453Chile Department of Internal Medicine Hospital del SalvadorSantiago 7500922Chile Department of Oncology Bradford-Hill Clinical Research CenterSantiago 8420383Chile

Colorectal cancer(CRC) is a major cause of mortality worldwide, associated with a steadily growing prevalence. Notably, the identification of KRAS, NRAS, and BRAF mutations has markedly improved targeted CRC therapy by affording treatments directed against the epidermal growth factor receptor(EGFR) and other anti-angiogenic therapies. However, the survival benefit conferred by these therapies remains variable and difficult to predict, owing to the high level of molecular heterogeneity among patients with CRC. Although classification into consensus molecular subtypes could optimize response prediction to targeted therapies, the acquisition of resistance mutations to targeted therapy is, in part, responsible for the lack of response in some patients. However, the acquisition of such mutations can induce challenges in clinical practice. The utility of liquid biopsy to detect resistance mutations against anti-EGFR therapy has recently been described. This approach may constitute a new standard in the decision algorithm for targeted CRC therapy.

关键词： Colorectal neoplasms Precision medicine Liquid biopsy Cetuximab Panitumumab

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Nesting innovations allow population growth in an invasive population of rose-ringed parakeets

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Current Zoology 2022年第6期68卷 617-626页

作者： Dailos HERNANDEZ-BRITO Jose L.TELLA guillermo BLANCO Martina CARRETE Department of Conservation Biology Donana Biological Station(CSIC)Calle Americo Vespucio26Sevilla 41092Spain Department of Evolutionary Ecology Museo Nacional de Ciencias Naturales(CSIC)Calle JoseGutierrez Abascal2Madrid 28006Spain Department of Physical Chemical and Natural SystemsUniversidad Pablo de OlavideCarretera de Utrerakm 1Sevilla 41013Spain

Certain traits of recipient environments,such as the availability of limiting resources,strongly determine the establishment success and spread of non-native *** limitations may be overcome through behavioral plasticity,allowing them to exploit alternative ***,we show how a secondary cavity nester bird,the rose-ringed parakeet Psittacula krameri,innovates its nesting behavior as a response to the shortage of tree cavities for nesting in its invasive range in Tenerife(Canary Islands).We observed that some breeding pairs excavated their own nest cavities in palms,thus becoming primary cavity nester,whereas others occupied nests built with wood sticks by another invasive species,the monk parakeet Myiopsitta *** use of these novel nesting strategies increased the number of breeding pairs by up to 52%over 6 years,contributing to a 128.8%increase of the whole *** nests were located at greater heights above ground and were more aggregated around conspecifics but did not result in greater breeding success than natural *** of monk parakeet colonies by rose-ringed parakeets also benefited the former species through a protective-nesting association against nest *** results show how an invasive species innovate nesting behaviors and increase nest-site availability in the recipient environment,thus facilitating its population growth and invasion *** behavioral innovations in other invasive rose-ringed parakeet populations may be overlooked,and should be considered for effective management plans.

关键词： antipredator response behavioral flexibility biological invasions cavity nesters nesting innovation reproductive success

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Comparison of total immunoglobulin A levels in different samples in Leghorn and broiler chickens

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Asian Pacific Journal of Tropical Biomedicine 2017年第2期7卷 116-120页

作者： Rubén Merino-Guzmán Juan David Latorre Ramiro delgado Xochitl Hernandez-Velasco Amanda Desha Wolfenden Kyle Dean Teague Lucas Elzie Graham Brittany Danielle Mahaffey Mikayla Francis Ann Baxter Billy Marshall Hargis guillermo Tellez College of Veterinary Medicine National Autonomous University of Mexico Department of Poultry Science University of Arkansas Nutriavicola

Objective: To standardize an ELIsa protocol to quantify total immunoglobulin A(IgA)from different biological ***: Two independent experiments were conducted. In Experiment 1, total IgA levels were quantified from the lachrymal fluid, tracheal swab, and cloacal swab at various time points from Days 30 to 89 in white Leghorn chickens. Experiment 2 was conducted to evaluate the effect of 50 or 500 ppb of aflatoxin B1(AFB1) on total IgA quantified in samples from the lachrymal fluid, tracheal swab, gut content and cloacal swab in broiler chickens at 21 days of ***: Lachrymal fluid contained the highest level of IgA; however, the sampling procedure was time consuming and stressful to the bird, and the sample volume depends largely on the size of the chicken. Cloacal swabs also contained a high concentration of IgA; this sampling procedure was faster than lachrymal fluid sampling and was not affected by the age of the bird. Tracheal sampling was more difficult than cloacal sampling; the age of the bird limited the sampling, and the IgA concentration was the lowest detected at all sampling ages. 500 ppb of AFB1 significantly reduced total IgA concentration in the gut content compared with control or 50 ppb of AFB1 treated ***, a significant reduction in total IgA was also observed in those chickens that received 50 ppb of AFB1 in gut rinse when compared with cloacal ***: The results of this study suggest that cloacal swab is an easy and reliable way to evaluate mucosal IgA concentration in both Leghorn and broiler chickens.

关键词： Immunoglobulin A ELIsa Chicken Lachrymal fluid

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Photoelectrochemical CO_(2) electrolyzers: From photoelectrode fabrication to reactor configuration

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Journal of Energy Chemistry 2023年第10期85卷 455-480,I0012页

作者： Jose Antonio Abarca guillermo Díaz-sainz Ivan Merino-Garcia Angel Irabien Jonathan Albo Departamento de Ingenierías Química y Biomolecular Universidad de CantabriaETSIITAvenida de los Castros s/n39005 SantanderSpain

The photoelectrochemical conversion of CO_(2) into value-added products emerges as an attractive approach to alleviate climate change. One of the main challenges in deploying this technology is, however, the development and optimization of(photo)electrodes and photoelectrolyzers. This review focuses on the fabrication processes, structure, and characterization of(photo)electrodes, covering a wide range of fabrication techniques, from rudimentary to automated fabrication processes. The work also highlights the most relevant features of(photo)electrodes, with special emphasis on how to measure and optimize them. Finally, the review analyses the integration of(photo)electrodes in different photoelectrolyzer architectures, analyzing the most recent research work that comprises photocathode, photoanode,photocathode-photoanode, and tandem photoelectrolyzer configurations to ideally achieve self-sustained CO_(2) conversion systems. Overall, comprehensive guidelines are provided for future advancements in developing effective devices for CO_(2) conversion, bridging the gap towards the use of sunlight as the unique energy input and practical applications.

关键词： Decarbonization CO_(2)photoelectroreduction (Photo)Electrodes Fabrication techniques Photoelectrolyzer configuration

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