1,560 research outputs found

    Produtividade e avaliação econÎmica de sistemas de integração lavoura-pecuåria-floresta, em Campo Grande, MS.

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    Dissertação em Zootecnia, årea de concentração em Produção Animal no Cerrado-Pantanal, da Universidade Estadual de Mato Grosso do Sul, título de Mestre em Zootecnia, sob a co-orientação do Professor Doutor Roberto Giolo de Almeid

    Diatom species fluxes in the seasonally ice-covered Antarctic Zone:. New data from offshore Prydz Bay and comparison with other regions from the eastern Antarctic and western Pacific sectors of the Southern Ocean

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    The Antarctic Zone, the southernmost belt of the Antarctic Circumpolar Current, plays an important role in the control of atmospheric carbon dioxide concentrations. In the last decade, a number of studies have highlighted the importance of diatom assemblage composition in influencing the magnitude of the organic carbon and biogenic silica fluxes exported out of the mixed layer in Southern Ocean ecosystems. Here we investigate the relationship between the makeup of the diatom assemblage, organic carbon and biogenic silica export and several significant environmental parameters using sediment trap records deployed in different sectors of the Antarctic Zone. The study is divided in two parts. We first present unpublished diatom species flux data collected by a sediment trap in the offshore waters of Prydz Bay (Station PZB-1) over a year. The results of this study revealed a major export peak of diatom valves in Austral summer and two small unexpected secondary flux pulses dining full winter conditions. The summer diatom sinking assemblages were largely composed of small and rapidly dividing species such as Fragilariopsis cylindrus, Fragilariopsis curta and Pseudo-nitzschia lineola, while winter assemblages were dominated by Fragilariopsis kerguelensis most reflecting its persistent strategy and selective preservation. In the second part of the study, we compare the annual diatom assemblage composition and biogeochemical fluxes of Station PZB-1 with flux data documented in previous sediment trap studies conducted in other sectors of the Antarctic Zone in order to investigate how diatom floristics influence the composition and magnitude of particle fluxes in the Antarctic Zone. The lack of correlation between the annual diatom valve, organic carbon and biogenic silica fluxes across stations indicates that other factors aside from diatom abundance play a major role in the carbon and silica export in AZ. Among these factors, the composition of the diatom assemblage appears to be critical, as suggested by the strong and significant correlation between Bio-SiO2 and the valve fluxes of F. kerguelensis alone, that this species is the main Bio-SiO2 vector from the surface layer to the deep ocean in the AZ waters, regardless of its relative abundance. Lastly, the good correlation between the annual fluxes of the group of small Fragilariopsis species with satellite-derived chlorophyll-a concentration estimates over the study stations, suggest that high abundances of these species in the Southern Ocean paleorecords could be used as a proxy of high algal biomass accumulation.NSFNational Science Foundation (NSF) [OPP-9726186]CCMAR [PEstC/MAR/LA0015/2013]info:eu-repo/semantics/publishedVersio

    Modeling the individual height and volume of two integrated crop-livestock-forest systems of Eucalyptus spp. in the Brazilian Savannah.

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    The aim of this study was to model the individual height and volume of eucalyptus wood in two integrated crop-livestock-forest systems (ICLF1 and ICLF2) in Campo Grande, a city in the state of Mato Grosso do Sul, Brazil. Classic nonlinear growth models were adjusted for height (Logistic, Gompertz, Richards, Weibull, Van Bertalanffy, Brody, Mitscherlich, and Chapman and Richards) and volume (Shumacher-hall nonlinear, Takata, Honner, Logistic, Gompertz, and Weibull) in two structural arrangements: ICLF1, with a spacing of 14 x 2 m and density of 357 trees ha-1, and ICLF2, with a spacing of 22 x 2 m and density of 227 trees ha-1. Diameter at Breast Height (DBH) measurements were performed in 100% of trees, with measurements of the total height of some individuals and a rigorous scaling procedure in diameter classes. According to the calculated value of Student's t-test, there was no significant evidence that DBH and the average height of the trees were different between ICLF1 and ICLF2. Based on the Akaike information criterion (AIC), the corrected Akaike information criterion (AICC) and the Bayesian information criterion (BIC), the Richards model was selected to estimate heights and the Takata model was selected to estimate the volume

    Whale sharks as oceanic nurseries for Golden Trevally

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    The Golden Trevally, Gnathanodon speciosus, is a large predatory fish with an extremely broad tropical Indo-Pacific distribution that crosses many biogeographical boundaries. Both published information and freely available imagery suggest that small juvenile G. speciosus are often associated with whale sharks, Rhincodon typus; an association that could explain the unusually widespread distribution of G. speciosus, and suggests a novel nursery relationship. The possibility of such an association has the potential to reshape our understanding of the ecological roles played by long-range migrants such as R. typus and other megafauna, our understanding of the full extent of their conservation value, and how we manage both members of the relationship

    Oxidative Stress, DNA, Cell Cycle/Cell Cycle Associated Proteins and Multidrug Resistance Proteins: Targets of Human Amniotic Membrane in Hepatocellular Carcinoma

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    The anticancer effects of human amniotic membrane (hAM) have been studied over the last decade. However, the action mechanisms responsible for these effects are not fully understood until now. Previously results reported by our team proved that hAM is able to induce cytotoxicity and cell death in hepatocellular carcinoma (HCC), a worldwide high incident and mortal cancer. Therefore, this experimental study aimed to investigate the cellular targets of hAM protein extracts (hAMPE) in HCC through in vitro studies. Our results showed that hAMPE is able to modify oxidative stress environment in all HCC cell lines, as well as its cell cycle. hAMPE differently targets deoxyribonucleic acid (DNA), P21, P53, ÎČ-catenin and multidrug resistance (MDR) proteins in HCC cell lines. In conclusion, hAMPE has several targets in HCC, being clear that the success of this treatment depends of a personalized therapy based on the biological and genetic characteristics of the tumor

    Cultural Adaptation and Validation of the Portuguese Version of the CANHELP Lite Bereavement Questionnaire

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    Satisfaction with care is an important outcome measure in end-of-life care. Validated instruments are necessary to evaluate and disseminate interventions that improve satisfaction with care at the end of life, contributing to improving the quality of care offered at the end of life to the Portuguese population. The purpose of this study was to perform a cross-cultural adaptation and psychometric analysis of the Portuguese version of the CANHELP Lite Bereavement Questionnaire.info:eu-repo/semantics/publishedVersio

    A capacity management tool for a portfolio of industrialization projects

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    The management of a project portfolio is a complex decision process because it encompasses the achievement of multiple objectives. A critical point that increases the complexity in the decision-making process of a portfolio manager is the allocation of human resources to manage the projects of the portfolio, project managers, which is crucial to the organization’s performance. In this case, the project manager can manage more than one project simultaneously and it is necessary to assign project managers to the projects, considering that project activities have an amount of work to be accomplished. The main objective of this work was to provide support for this capacity management problem, which aims to provide an easier decision-making process for the capacity management of an industrialization project portfolio. Therefore, it was developed: a hybrid model that creates a schedule respecting the resource constraints and the established due dates; a recommendation system that considers project managers’ allocation and projects requirements; and, an automatic status report that allows identifying the project portfolio capacity usage.This work is supported by: European Structural and Investment Funds in the FEDER component, through the Operational Competitiveness and Internationalization Programme (COMPETE 2020) [Project nÂș 39479; Funding Reference: POCI-01-0247-FEDER-39479]

    Evolution of oxygen-ion and proton conductivity in Ca-Doped Ln2Zr2O7 (Ln = Sm, Gd), located near pyrochlore fluorite phase boundary

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    Sm2-xCaxZr2O7-x/2 (x = 0, 0.05, 0.1) and Gd2-xCaxZr2O7-x/2 (x = 0.05, 0.1) mixed oxides in a pyrochlore-fluorite morphotropic phase region were prepared via the mechanical activation of oxide mixtures, followed by annealing at 1600 ?C. The structure of the solid solutions was studied by X-ray diffraction and refined by the Rietveld method, water content was determined by thermogravimetry (TG), their bulk and grain-boundary conductivity was determined by impedance spectroscopy in dry and wet air (100-900 ?C), and their total conductivity was measured as a function of oxygen partial pressure in the temperature range: 700-950 ?C. The Sm2-xCaxZr2O7-x/2 (x = 0.05, 0.1) pyrochlore solid solutions, lying near the morphotropic phase boundary, have proton conductivity contribution both in the grain bulk and on grain boundaries below 600 ?C, and pure oxygen-ion conductivity above 700 ?C. The 500 ?C proton conductivity contribution of Sm2-xCaxZr2O7-x/2 (x = 0.05, 0.1) is ~ 1 ? 10-4 S/cm. The fluorite-like Gd2-xCaxZr2O7-x/2 (x = 0.1) solid solution has oxygen-ion bulk conductivity in entire temperature range studied, whereas proton transport contributes to its grain-boundary conductivity below 700 ?C. As a result, of the morphotropic phase transition from pyrochlore Sm2-xCaxZr2O7-x/2 (x = 0.05, 0.1) to fluorite-like Gd2-xCaxZr2O7-x/2 (x = 0.05, 0.1), the bulk proton conductivity disappears and oxygen-ion conductivity decreases. The loss of bulk proton conductivity of Gd2-xCaxZr2O7-x/2 (x = 0.05, 0.1) can be associated with the fluorite structure formation. It is important to note that the degree of Ca substitution in such solid solutions (Ln2-xCax)Zr2O7-? (Ln = Sm, Gd) is low, x < 0.1. In both series, grain-boundary conductivity usually exceeds bulk conductivity. The high grain-boundary proton conductivity of Ln2-xCaxZr2O7-x/2 (Ln = Sm, Gd; x = 0.1) is attributable to the formation of an intergranular CaZrO3-based cubic perovskite phase doped with Sm or Gd in Zr sublattice. ? 2019 by the authors.371C-9F16-EBDE | Eduarda GomesN/

    The effects of online negative word‐of‐mouth on dissatisfied customers:A frustration–aggression perspective

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    Conceptualizing how customers construe online negative word‐of‐mouth (nWOM) following failure experiences remains unsettled, leaving providers with inconclusive recovery strategy programmes. This empirical study recognizes online nWOM as a co‐created encounter between the complainant (i.e., the initiator of the online nWOM) and the recipient (i.e., the consumer who engages with the online nWOM), examining their idiosyncrasies to discern their understanding of the experience. It introduces frustration–aggression theory to online WOM literature, recognizing that it can support a higher‐order understanding of phenomena. Through phenomenological hermeneutics, interviews and focus groups, data were collected from millennials in Albania and Kosovo that provided accounts of nuanced and distinctive online nWOM realities. The emerged insights extended extant theory to a three‐fold online nWOM typology (i.e., lenient online nWOM, moderate online nWOM and severe online nWOM) recognizing the negative impact customers have on a provider, which is controlled by frustration–aggression tags. Frustration–aggression variations across online nWOM led to the construct of three types of customers that engage in online nWOM, namely tolerable online nWOM customers, rigorous online nWOM customers and confrontational online nWOM customers. Findings culminated with satisfactory recovery strategies aligned to customer inferences regardless of the nWOM context
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