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Evaluation and modeling of runoff and sediment yield for different land covers under simulated rain in a semiarid region of Brazil

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International Journal of Sediment Research 2018年第2期33卷 117-125页

作者： Richarde Marques da Silva Celso Augusto Guimares Santos José Yure Gomes dos Santos Department of Geosaences Federal University of Paraíba Department of Civil and Environmental Engineering Federal University of Paraíba federal University of Western Bahia Center for Humanities

This paper quantifies the runoff and sediment yield for four different land covers in a semiarid region of Brazil. The WESP model, a distributed, event-oriented runoff-erosion model, was applied and its physical parameters, nSand KR, were adjusted based on observed runoff and sediment yield data using simulated rainfall with an average intensity of 53 mm h-1. The sediment yield obtained was 53.02 kg ha-1(caatinga vegetation), 231.96 kg ha-1(bare soil), 309.75 kg ha-1(beans), and 847.38 kg ha-1(corn). The results showed that caatinga cover yields the lowest erosion and runoff when compared to the other *** results also show that the sediment yield and runoff values simulated with nS, KI, and KR parameters were well calibrated, within acceptable deviations. The caatinga vegetation was more effective in protecting the soil, when compared to the other types of coverage. The beans and corn covers had the highest values of runoff and sediment yield, even higher than those observed for bare soil.

关键词： Runoff Erosion Semiarid region WESP model

neurogenesis in the hippocampus of adult humans: controversy “fixed” at last

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neural Regeneration Research 2019年第11期14卷 1917-1918页

作者： Silene M.A. Lima Walace Gomes-Leal laboratory of neurobiology Institute of Biological SciencesFederal University of ParaBelem-ParaBrazil laboratory of Experimental neuroprotection and neuroregeneration Institute of Biological SciencesFederal University of ParaBelem-ParaBrazil

The presence of adult neurogenesis in the mammalian brain has been a theme of intense controversy for a long time since the original report by Altman and Das (1965). The scientific community, for about 30 years, has difficulties to accept that progenitor cells give rise to new neurons in some specific regions of the mammalian adult brain, the neurogenic niches (Kuhn et al., 1996;Doetsch et al., 1997, 1999).

关键词： neurogenesis hippocampus mammalian brain

Geological setting, mining and reduction of mercury vapor contamination in the gold-silver district of Vetas-Calofornia （Santander, Colombia）

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Episodes 2005年第4期28卷 252-256页

作者： Erwin Wolff Carreno Juan Manuel Pinzon Angel Rodolfo Contreras Moreno Christoph Bernardy Corporacion Autonoma Regional para la Defensa de la Mescta de Bucaramanga Carrera 23 N°37-63 Bucaramanga Colombia Formely with Corporacidn Autonoma Regional para la Defensa de la Mescta de Bucaramanga Carrera 23 N°37-63 Bucaramanga Colombia. Formerly with federal Institute for Geosciences and natural Resources Stilleweg 2 30655 Hannover Germany

Bucaramanga, with a population of about one million, is the capital of the Department of Santander （Colombia）, and has the Rio Surata as its main source of drinking water. In the upper reaches of the river, small-scale gold mining has been going onfor many centuries （Vetas-California mining district）. Geologically, the Vetas-California mining district is part of the Santander Massif which is composed of pre-Devonian metamorphic rocks and Mesozoic igneous rocks. The mineralisation is restricted to structurally controlled veins and is often associated with hydrothermal alteration. There is also disseminated mineralisation, but presently only the vein-type is mined. The processing residues are discharged into the nearby watercourses, contaminating the waters of the Surata river basin. As part of a joint Colombian-German technical cooperation project, with the purpose of controlling the negative environmental effects of gold mining pollution, an integrated distillation system for the recovery of mercuury. has been designed and tested.

关键词：地质条件矿床哥伦比亚蒸发作用金银

Charged scalar fields in a Kerr-Sen black hole:exact solutions, Hawkingradiation, and resonant frequencies

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Chinese Physics C 2019年第3期43卷 91-98页

作者： H.S.Vieira V.B.Bezerra Departamento de Física Universidade Federal da Paraíba

In this study, we consider charged massive scalar fields around a Kerr-Sen spacetime. The radial and angular parts of the covariant Klein-Gordon equation are solved in terms of the confluent Heun function. From the exact radial solution, we obtain the Hawking radiation spectrum and discuss its resonant frequencies. The massless case of the resonant frequencies is also examined.

关键词： Klein-Gordon equation charged and rotating black hole heterotic string field theory confluent Heun function black hole physics

A spatial framework for detecting anthropogenic impacts on predator-prey interactions that sustain ecological integrity in Mexico

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Ecological Processes 2018年第1期7卷 408-424页

作者： Franz Mora Coordinación del Sistema de Información Espacial para el Soporte de Decisiones sobre Impactos a la Biodiversidad.Comisión nacional para el Conocimiento y Uso de la Biodiversidad(COnABIO) Liga Periférico-Insurgentes SurNúm.4903Col.Parques del Pedregal14010 Delegación TlalpanMexico

Background:This paper presents several spatial indicators developed to evaluate anthropogenic impacts on predator-prey interactions and their relationship with ecological integrity loss in *** integrity loss is defined as the inability to sustain viable populations,habitat functions,and species interactions of nearctic and neotropical apex predators as a result of anthropogenic *** direct impacts,the indicators evaluate habitat loss and the number of inhospitable *** indirect impacts,the indicators evaluate the avoidance of human features such as highways,roads,and human *** total impact level is described at 1 km^(2) resolution,and registered within the domain defined by the spatial habitat requirements of apex *** impact level is associated with ecological integrity loss,or the ecosystem capacity to reorganize habitat functions and sustain predator-prey interactions as the most visible elements of ecological *** integrity loss is evaluated for different groups of apex predators that are classified with different levels of anthropogenic ***:The framework presented here identifies the spatial information needed for the assessment of cumulative anthropogenic *** characterizing their distribution range,nearctic predators have significantly larger intact habitats than neotropical predators but with higher ecological degradation,less landscape transformation,and overall less ecological *** observed within their distribution areas,indirect impacts have a generalized effect in the broad range of landscapes in *** integrity loss is the result of road,highway,and human settlement avoidance;but landscape transformation and human activity control the threshold for which ecological integrity loss becomes *** the other hand,there are no significant differences in impact levels among threat conservation categories for apex predators,which indicate that all predator

关键词： Anthropogenic impacts Ecological integrity Spatial indicators Apex predators Impact assessment

Ecophysiology and multivariate analysis for production of Tachigali vulgaris in Brazil:Influence of rainfall seasonality and fertilization

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Journal of Forestry Research 2023年第5期34卷 1289-1305页

作者： Pedro Henrique Oliveira Simoes Candido Ferreira de Oliveira neto Manoel Tavares de Paula Dênmora Gomes de Araújo Rodrigo Silva do Vale Joao Olegário Pereira de Carvalho Universidade federal de Mato Grosso Campus Universitario de SinopSinop 78550728Mato GrossoBrazil Universidade federal Rural da Amazonia Campus BelemBelem 66077830ParaBrazil Universidade do Estado do para Centro de Ciencias Naturais e TecnologiaBelem 66095015ParaBrazil Universidade federal Rural da Amazonia Campus Capitao-PocoCapitao Poco 68650000ParaBrazil

Studies on fertilization management of species native to the Amazon for energy plantations contribute to the diversity of species use and reduce biological risk due to the excessive use of clones or hybrids of *** study evaluates the effect of precipitation seasonality and phosphorus and potassium fertilization on gas exchange in a Tachigali vulgaris *** levels of P(zero,65.2,130.4 kg ha^(-1))and three of K(zero,100.0,200.0 kg ha^(-1))were applied in a 3×3 factorial randomized block *** exchange measurements were conducted in April and november *** low rainfall,high irradiance period,photo synthetic rates were up to four times higher than in the high rainfall period,reaching 20.3μmol m^(-2)s^(-1)in the treatment with 130.4 g kg^(-1)of P and 100.0 g kg^(-1)of *** analysis and principal component analysis reduced the initial eight gas exchange variables to two and three principal components in periods of high and low rainfall,*** multivariate method used in this study readily identified variations in the variables as a function of rainfall,with high reliability in explaining the data set.

关键词： Photosynthesis rate Stomatal conductance Principal component analysis Factor analysis Tachigali vulgaris

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Insights into gastric neuroendocrine tumors burden

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Chinese Journal of Cancer Research 2017年第2期29卷 137-143页

作者： Taíssa Maíra Thomaz Araújo Williams Fernandes Barra André Salim Khayat Paulo Pimentel de Assumpcao Oncology Research Center Federal University of paráPara 66073-005Brazil

Type 1 gastric neuroendocrine tumors （gnETs） are usually small lesions, restricted to mucosal and sub-mucosal layers of corpus and fundus, with low aggressive behavior, for the majority of cases. nevertheless, some cases present aggressive behavior. The increasing incidence of gnETs brings together a new relevant problem： how to identify potentially aggressive type I gnETs. The challenging problem seems to be finding out signs or features able to predict potentially aggressive cases, allowing a tailored approach, since the involved societies dedicated to provide guidelines for management of these neoplasms apparently failed in producing staging systems able to accurately predict prognosis of these tumors. Additionally, it is also important to try to find out explanations for increasing incidence, as well as to identify potential targets aiming to reach better control of this neoplasia. Here, we discuss potential pathways implicated in aggressive behavior, as well as new strategies to improve clinical management of these tumors.

关键词： gnETs gastrin receptor epidemiology

Association between Helicobacterpylori, Epstein-Barr virus, human papillomavirus and gastric adenocarcinomas

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World Journal of Gastroenterology 2018年第43期24卷 4928-4938页

作者： Carolina Rosal Teixeira de Souza Marcelli Carolini Alves Almeida Andre Salim Khayat Emerson Lucena da Silva Paulo Cardoso Soares Luiz Claudio Chaves Rommel Mario Rodriguez Burbano laboratory of Human Cytogenetics Institute of Biological Sciences Federal University of Para Belem Para 66075-110 Brazil Oncology Research Center Federal University of Para Joao deBarros Barreto University Hospital Belem Para 66073-000Brazil Ophir Loyola Hospital Belem Para 66060-281 Brazil

AIM TO correlate Helicobacter pylori （H. pylorli）, EpsteinBarr virus （EBV） and human papillomavirus （HPV） with gastric cancer （GC） cases in para State, *** Tissue samples were obtained from 302 gastric adenocarcinomas. A rapid urease test was used to detect the presence of H. pylori, and the presence of the cagA gene in the HP-positive samples was confirmed by PCR. An RnA in situ hybridization test designed to complement Eberl RnA was used to detect the presence of EBV in the samples, and the L1 region of HPV was detected using nested PCR. Positive HPV samples were genotyped and analyzed for E6 and E7 viral gene expression. Infections were also correlated with the clinical and pathological characteristics of the *** The majority of the 302 samples analyzed were obtained from men （65%） aged 55 years or older （67%） and were classified as the intestinal subtype （55%）. All three pathogens were found in the samples analyzed in the present study （H. pylori： 87%, EBV： 20%, HPV： 3%）. Overall, 78% of the H. pylori-positive （H. pylorl＋） samples were cagA＋（H. pylori-cagA＋）, and there was an association between the cytotoxic product of this gene and EBV. Coinfections of H. pylori-cagA＋ and EBV were correlated with the most advanced tumor stages. Although only 20% of the tumors were positive for EBV, infection with this virus was associated with distant metastasis. Only the HPV 16 and 18 strains were found in the samples, although no expression of the E6 and E7 oncoproteins was detected. The fundus of the stomach was the region least affected by the *** HPV was not involved in gastric tumorigenesis. Prophy- lactic and therapeutic measures against H. pylori and EBV may prevent the development of GC, especially the more aggressive forms.

关键词： Gastric cancer Gastric adenocarcinomas Microorganisms Helicobacter pylori cagA Epstein-Barr virus Human papillomavirus

Removing contaminants from tannery wastewater by chemical precipitation using CaO and Ca(OH)2

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1107-1111页

作者： Adriana Reyes-Serrano Joel ELópez-Alejo Manuel AHernández-Cortázar Ignacio Elizalde Instituto Politécnico nacional Centro Mexicano para la Producción más LimpiaCiudad de México 07340Mexico

The removal of Cr,sulfates and Chemical Oxygen Demand(COD)from industrial tannery wastewater by chemical precipitation was carried out using Calcium oxide(CaO)and Calcium hydroxide(Ca(OH)2).Different doses of alkalis,ranging from deficiency to excess hydroxyl species over the stoichiometric necessary,were used to remove theoretically the 100%of Cr[0.3-3.2 g alkali·(g Cr^3+)^-1].The precipitation was carried out at room temperature,10 min of vigorous stirring,200 r·min^-1 and a settling time of 24 h,followed by separation and characterization of liquid *** result of addition of alkalis,pH underwent increase as did the alkali *** removal of Cr,and sulfates also increased as alkali concentration did,although for first species the changes at higher alkali contents were less *** removal on the other hand,did not follow a unique trend,instead exhibited a *** on our results,selection of a specific dose of alkali was carried out taking as reference the efficiency on total chromium removal,keeping the pH in the range 7 to 9 to ensure Cr precipitation as chromium *** those conditions,jar test was used to produce enough liquid product in order to determine the removal percent of several other *** removal percent of the species was as follows:Cr,SO4^2-,ZnSO4,FeSO4,Cn^-1,niSO4,Fe2[Fe(Cn)6]at 99.8%,66.9%,99.6%,21.4%,70.9%,52.8%and 76.4%with CaO,and 99.8%,61.6%,99.9%,7.1%,84.0%,54.4%and 90.5%with Ca(OH)2,respectively.

关键词： Tannery wastewater Alkali Removal Chromium Sulfates Synergistic effect