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Unpaved rural roads as source areas of sediment in a watershed of the Brazilian semi-arid region

International Journal of Sediment Research 2019年第5期34卷 475-485页

作者： Teresa Raquel lima Farias Pedro henrique Augusto Medeiros Joaquín Navarro-Hevia José Carlos de Araújo Federal Institute of Education Science and Technology of Ceará University of Valladolid Campus La Yutera Federal University of Ceará Department of Agricultural Engineering Campus do Pici

Approximately 80% of the road network in Brazil is unpaved and shows evidences of a high erosion potential. In the semi-arid Caatinga Biome in the northeast of the country, a monitoring programme has been done for two years in order to analyze runoff and sediment production from unpaved rural roadways and from embankments. Sediment production ranged from 0.30 to 0.92 Mg/ha yr, higher than in undisturbed areas, but generally lower than that reported for unpaved roads in other regions. However,this is a semi-arid area with low rainfall and runoff and, hence, with a limited hydrological connectivity and sediment production. Sediment production on an embankment with no vegetation was around ten times higher than on an embankment with vegetation. On the road surface, annual sediment production(normalized for gradient) in a section with traffic was three times higher than for a road surface without traffic. In addition, events that occurred after roadway maintenance activities generated peaks of sediment concentration of over 5000 mg/l. These results suggest that sediment production from roads and embankments with bare surfaces is at least one order of magnitude higher than in undisturbed catchment areas. Maintenance activity and vehicle traffic contribute to an increase in sediment availability and impact on the sediment concentration, but less intensely on sediment loads, which depend on the runoff magnitude of the events occurring after roadway maintenance. It was also found that the natural vegetation of the semi-arid region potentially captures sediment on roadway embankments; thereby playing an important role in breaking connectivity between the sediment flow from unpaved roads and the natural drainage system of the catchment.

关键词： Sediment production Caatinga vegetation Road maintenance Embankment

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The role of hypoxia-induced factor 1α in breast cancer

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Journal of Cancer Metastasis and Treatment 2019年第6期4卷 44-54页

作者： Carlos henrique F.Peiró Jéssica A.Encina Matheus M.Perez Glauco S.A.Aquino Glaucia l.Veiga Fernando Fonseca Beatriz C.A.Alves laboratório de Análises Clínicas da Faculdade e Medicina do ABC Santo AndréSP CEP 09060-650Brazil Instituto de Ciências Farmacêuticas Universidade Federal de São PauloDiademaSP CEP 09972-270Brazil

Breast cancer usually grows very quickly,becoming insensitive to blood flow in nearby veins;because of that,inside solid tumors it's possible to find a hypoxic environment,in other words,an environment where oxygen is less *** feature of cancer is its angiogenesis rate,because of the high energy demand,new blood vessels must be produced to take nutrients inside the solid tumor *** with normal blood flow bringing the cancer oxygen and nutrients,its cells favor hypoxia,in an event known as Warburg *** to the Warburg Effect,cells,even with normal oxygen rates,prefer to use fermentation instead of the citric acid cycle to produce *** the cancer to operate normally in hypoxia,a transcription factor family is activated,known as hypoxia-induced factors(HIF),composed of a HIF-1βand a HIF-1α*** HIF-1αis expressed during hypoxia,it is a great target for treatments and a breast cancer *** of the role of HIF-1αin cancer and the high incidence of breast cancer worlwide,this review was performed in order to bring the most recent results concerning the role HIF-1αcan exert in breast cancer development and progression.

关键词： Breast neoplasms hypoxia-induced factor 1 HIF-1α

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Circulating leptin and its muscle gene expression in Nellore cattle with divergent feed efficiency

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Journal of Animal Science and Biotechnology 2018年第1期9卷 228-232页

作者： lúcio Flávio Macedo Mota Cristina Moreira Bonafé Pamela Almeida Alexandre Miguel henrique Santana Francisco JoséNovais Erika Toriyama Aldrin Vieira Pires Saulo da luz Silva Paulo Roberto leme JoséBento Sterman Ferraz Heidge Fukumasu Departmento de Zootecnia Universidade Federal dos Vales do Jequitinhonha e MucuriDiamantinaMG 39100 000Brazil Faculdade de Ciencias Agrarias e Veterinarias Universidade Estadual Paulista JaboticabalSP 14884 900Brazil Departamento de Medicina Veterinaria Faculdade de Zootecnia e Encjenharia de AlimentosUniversidade de Sao PauloAM.Duque de Caxias Norte n225Pirassununcja 13635 900SPBrazil Departmento de Zootecnia e Desenvolvimento Acjrossocioambiental Sustentavel Faculdade de VeterinariaUniversidade Federal FluminenseNiteroiRJ 24230 340Brazil Departamento de Zootecnia Faculdade de Zootecnia e Engenharia de AlimentosUniversidade de Sao PauloPirassununga 13635-900SPBrazil

Background： leptin has a strong relation to important traits in animal production, such as carcass composition,feed intake, and reproduction. It is mainly produced by adipose cells and acts predominantly in the *** this study, circulating leptin and its gene expression in muscle were evaluated in two groups of young Nellore bulls with divergent feed efficiency. Individual dry matter intake（DMI） and average daily gain（ADG） of 98 Nellore bulls were evaluated in feedlot for 70 d to determinate the residual feed intake（RFI） and select 20 animals for the high feed efficient（lRFI） and 20 for the low feed efficient（HRFI） groups. Blood samples were collected on d 56 and at slaughter（80 d） to determine circulating plasma leptin. Samples of longissimus dorsi were taken at slaughter for leptin gene expression ***： DMI and RFI were different between groups and lRFI animals showed less back fat and rump fat thickness,as well as less pelvic and kidney fat weight. Circulating leptin increased over time in all animals. Plasma leptin was greater in lRFI on 56 d and at slaughter（P = 0.0049）. Gene expression of leptin were greater in lRFI animals（P = 0.0022） in accordance with the plasma levels. The animals of the lRFI group were leaner, ate less, and had more circulating leptin and its gene ***： These findings demonstrated that leptin plays its physiological role in young Nellore bulls, probably controlling food intake because feed efficient animals have more leptin and lower residual feed intake.

关键词： Beef cattle Energy homeostasis Fat depositon Residual feed intake

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Changes in Spatiotemporal land Use Patterns in Selected Hydrogeomorphic Areas of China and the USA

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International Journal of Geosciences 2013年第3期4卷 537-548页

作者： Bin Quan Matt J.M.Romkens Ronald l.Bingner henrique Momm Darlene Wilcox Hunan Province Engineering laboratory of Geospatial Information Hunan University of Science and TechnologyXiangtanChina USDA/ARS National Sedimentation LaboratoryOxfordUSA Middle Tennessee State University MurfreesboroUSA

Differences exist in land use/cover pattern and its change between the P. R. China and the USA. In order to describe those differences, land use changes in representative regions were quantitatively analyzed and compared. Xiamen City, Changzhutan region and liupan Mountains regions were selected to represent three different hydrogeomorphic areas of eastern, central, and western China, respectively, while the Goodwin Creek Experimental Watershed (GCEW) located in the north-central part of Mississippi in the bluff hills just east of the Mississippi River floodplain was chosen in the USA. By integrating historical landsat TM imagery and geographical information system data, the spatiotemporal land use dynamics and conversion of land use in China and the USA between 1980 and 2010 were explored and compared. Results indicated an urban sprawl in eastern and central China, which encroached upon large amount of cropland, forest land and grassland. On the other hand, western China reclaimed cropland from grassland, forest land, which led to severe soil erosion between 1990 and 2000. Goodwin Creek Watershed of the USA converted 73.3% of the lost cropland into forest land, pasture and idle land, which accounted for about 90% in 2010. Further, counter-urbanization occurs in the GCEW due to favorable eco-environment for living. Compared with the land dynamic degree of the GCEW, eastern China is greater than it;western China is smaller than it while central China is almost equal to it. And the land use intensity index of GCEW is smaller than that of China all these years. Eastern China advocated ecological civilization in 2007 to meet the serious challenges of sustainable development. Western China started the Return of land from Farming to Forestry and Grassland Project in 2000. The Changzhutan region in central China is served as the resource-saving and environment-friendly community in 2007, which will be favorable for the sustainable land utilization and protection of ecology

关键词： land Use/land Cover Change Geographical Information System Remote Sensing China USA

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Geochemical study of submicron particulate matter(PM1)in a metropolitan area

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Geoscience Frontiers 2022年第1期13卷 417-429页

作者： Ismael l.Schneider Elba C.Teixeira Guilherme l.Dotto Diana Pinto Cheng-Xue Yang luis F.O.Silva Postgraduate Program in Remote Sensing and Meteorology Universidade Federal do Rio Grande do SulAv.Bento Gonçalves9500 Porto AlegreRSBrazil Department of Civil and Environmental Universidad de la CostaCUCCalle 58#55-66BarranquillaAtlanticoColombia Research Department Fundação Estadual de Proteção Ambiental Henrique Luís RoesslerAv.Borges de Medeiros261Porto AlegreRSBrazil Chemical Engineering Department Federal University of Santa Maria97105-900 Santa MariaBrazil School of Earth Sciences and Resources China University of Geosciences BeijingBeijing 100083PR China Departamento de Ingeniería Civil y Arquitectura Universidad de LimaAvenida Javier Prado Este 4600–Santiago de Surco 1503Perú

Air pollution has become a major problem in urban areas due to increasing industrialization and *** this study ambient concentrations of PM1 and metal concentrations as well as source contributions were identified and quantified by using Positive Matrix Factorization(PMF)in receptor modeling in the Metropolitan Area of Porto Alegre,*** PM1 samples were collected on PTFE filters from December 2012 to December 2014 in two sampling *** ion and trace element concentrations were *** average concentrations were 12.8 and 15.2μg/m^(3) for Canoas and Sapucaia do Sul sites,*** ion contributions of PM1 were secondary pollutants such as sulfate and *** elements,especially Cu,Pb,Zn,Cd,and Ni also made important contributions which are directly associated with anthropogenic *** results show significantly higher levels in winter than in *** of the PM1 and the analyzed PM species and elements originated from anthropogenic sources,especially road traffic,combustion processes and industrial activities,which are grouped in 7 major contributing sources.A back-trajectory analysis showed that the long-range transport of pollutants was not relevant in relation to the contribution to PM1 and metal *** work highlights the importance of urban planning to reduce human health exposure to traffic and industrial emissions,combined with awareness-raising actions for citizens concerning the impact of indoor sources.

关键词： PM1 Trace elements Source apportionment PMF Back trajectory

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Conocarpus erectus l., a plant with a high content of structural sugars, ions and phenolic compounds, shows antioxidant and antimicrobial properties promoted by different organic fractions

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Asian Pacific Journal of Tropical Biomedicine 2018年第9期8卷 463-470页

作者： Dayane Kelly Dias do Nascimento Santos Weslley henrique de Oliveira Melo Anastassia Mariáh Nunes de Oliveira lima Iranildo Joseda Cruz Filho Glaucia Manoella de Souza lima Tulio Diego da Silva Maiara Celine de Moura Marcia Silva do Nascimento Ana Maria Souto Maior Thiago henrique Napoleao Cristiane Moutinho lagos de Melo Department of Biochemistry Biosciences Centre Federal University of Pernambuco Department of Antibiotics Biosciences Centre Federal University of Pernambuco Center of Strategic Technologies of the Northeast

Objective: To evaluate the structural and chemical composition of plant and the antioxidant and antimicrobial activities promoted by hexanic, ethanolic and ethyl acetate fractions obtained from leaves of Conocarpus ***: Organic fractions were characterized through UPlC-MS and *** potential was performed through DPPH and molybdenum phosphate *** and antifungal assays were performed in accordance with Clinical and laboratory Standards Institute ***: The obtained biomass of Conocarpus erectus leaves showed the high presence of glucose(0.45 g/l), cellulose(28.69%), Na(55.126 μg/l) and K(31.163 μg/l).We identified seven compounds in the hexanic and ethyl acetate fractions, and eight compounds in ethanolic ***, phenolic compounds are prevalent in all organic fractions with values of(10.04 ± 0.24),(221.26 ± 1.84),(340.53 ± 0.84) mg/g GAE to hexanic, ethyl acetate and ethanolic fraction, *** results showed a high potential in ethyl acetate fraction(71.82 ± 6.87)% and(10.89 ± 0.05)% in DPPH and molybdenum phosphate techniques, *** ethanolic fraction showed moderate bacteriostatic and bactericidal activity against Staphylococcus aureus and presented a high fungistatic potential for all Candida species ***: Organic fractions obtained from leaves of Conocarpus erectus present antimicrobial and antioxidant properties, and these findings contribute to scientific information for the effectiveness on use of this plant in the development of a phytotherapic compound.

关键词： Combretaceae Phenolic compounds Antimicrobial activity Antioxidant

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lC–MS characterization, anti-kinetoplastide and cytotoxic activities of natural products from Eugenia jambolana lam. and Eugenia uniflora

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Asian Pacific Journal of Tropical Biomedicine 2017年第9期7卷 836-841页

作者： Celestina Elba Sobral de Souza Ana Raquel Pereira da Silva Janaina Esmeraldo Rocha Maria Celeste Vega Gomez Míriam Rolóm Cathia Coronel José Galberto Martins da Costa Manoel l.C.Netto larissa A.Rolim henrique Douglas Melo Coutinho laboratório de Microbiologia e Biologia Molecular Universidade Regional do Cariri Center for the Development of Scientific Research Moisés Bertoni Foundation/Díaz Gill Laboratories laboratório de Pesquisa de Produtos Naturais Universidade Regional do Cariri Centro Universitário Dr.leao Sampaio–UNIlEAO Universidade Federal do Vale do Sao Francisco–UNIVASF

Objective: To evaluate the trypanocidal, leishmanicidal and cytotoxic activity of Eugenia jambolana(E. jambolana) and Eugenia uniflora(E. uniflora) extracts and ***: The products were characterized by lC–MS. Antiparasitic assays were performed and cytotoxicity was evaluated in fibroblastos. In vitro assays were performed using spectrophotometric evaluation. All assays were performed in ***: The results showed that the extracts and the tannic fraction from E. jambolana inhibited 100% of the epimastigote lines. The ethanolic extract was the most efficient in all concentrations tested against the three parasite strains. In the cytotoxicity assay the flavonoid fraction showed low toxicity. All E. uniflora samples showed cytotoxicity at the highest concentration tested, but the extract showed no toxic effect on the fibroblasts at the lowest concentration. The flavonoid and tannic fractions were more efficient against leishmania braziliensis promastigotes compared to the extract. However, the extracts and the tannic fraction were more effective against leishmania infantum strains. The effect on epimastigote cells was observed at all concentrations tested, with all E. uniflora samples. However, the samples were more effective at the highest concentration, where there was inhibition in 100% of the Trypanosoma cruzi ***: The species E. jambolana and E. uniflora presented antiparasitic activity against all tested parasite strains, indicating that these species can serve as an alternative therapy as they were efficient in the tests performed. The E. uniflora extract and the E. jambolana flavonoid fraction presented a low cytotoxicity, opening the floor for new biological studies.

关键词： Antiparasitic effect Cytotoxicity Eugenia jambolana Eugenia uniflora

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An Auto-Zero Sample-and-Hold Circuit in 0.8μm CMOS

An Auto-Zero Sample-and-Hold Circuit in 0.8μm CMOS

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第五届专用集成电路国际会议（ASICON）

作者： luis henrique C.Ferreira Tales C.Pimenta Robson l.Moreno Microelectronics Group Universidade Federal de Itajuba-UNIFEI Av. BPS 1303 Itajuba-MG 37500-903 BRAZIL Microelectronics Group Universidade Federal de Itajuba-UNIFEI Av. BPS 1303 Itajuba-MG 37500-903 BRAZIL Microelectronics Group Universidade Federal de Itajuba-UNIFEI Av. BPS 1303 Itajuba-MG 37500-903 BRAZIL

＜正＞ This work describes the silicon implementation of a new sample-and-hold circuit topology. The main feature of the circuit is its auto-zero capability. The auto-zero corrects the offset voltage generated by the transistor mismatch in the differential pair and the charge injected by the NMOS switches in the sampling capacitor. The circuit was implemented in 0,8μm CMOS process from AMS. The results, initially obtained from simulations, were compared to real laboratory measurements. The comparison indicates that the measurements and the simulated results have a very close correspondence. The circuit is capable of reducing the total sample-and-hold output error to just 0.14% at a sampling rate of 250KHz.

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Gold Characterization by MlA and Technological Tests-Discussion of Sample Preparation and Results

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矿物学报 2013年第S1期33卷 10-10页

作者： Carina Ulsen henrique Kahn Guilherme Nery Daniel Uliana Juliana l.Antoniassi University of Sao Paulo Polytechnic SchoolMining and Petroleum Engineering Department.So Paulo.Brazil

Gold has been present throughout the history of mankind and used to make jewelry and coins, and recently, acquired several industrial uses. The price of gold in international market had a significant increasing, surpassing 100% in the last five years. Thereby, deposits with low levels of gold content, gold with complex associations or in a very fine particle size became exploitable again, allowing new projects and expansion of existing ones. However, for maximum process efficiency is indispensable a deep knowledge of the characteristics of these minerals and their behavior in face of beneficiation processes. Consequently, an accurate routine for mineralogical and technological characterization is essential.

关键词： gold characterization image analysis sample preparation

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Effect of Terrestrial liDAR Point Sampling Density in Ephemeral Gully Characterization

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Open Journal of Modern Hydrology 2013年第1期3卷 38-49页

作者： henrique G. Momm Ronald l. Bingner Robert R. Wells Seth M. Dabney lyle D. Frees Department of Geosciences Middle Tennessee State University Murfreesboro USA National Sedimentation laboratory United States Department of Agriculture—Agricultural Research Service Oxford USA United States Department of Agriculture—Natural Resources Conservation Service Salina USA

Gully erosion can account for significant volumes of sediment exiting agricultural landscapes, but is difficult to monitor and quantify its evolution with traditional surveying technology. Scientific investigations of gullies depend on accurate and detailed topographic information to understand and evaluate the complex interactions between field topography and gully evolution. Detailed terrain representations can be produced by new technologies such as terrestrial liDAR systems. These systems are capable of collecting information with a wide range of ground point sampling densities as a result of operator controlled factors. Increasing point density results in richer datasets at a cost of increased time needed to complete field surveys. In large research watersheds, with hundreds of sites being monitored, data collection can become costly and time consuming. In this study, the effect of point sampling density on the capability to collect topographic information was investigated at individual gully scale. This was performed through the utilization of semi-variograms to produce overall guiding principles for multi-temporal gully surveys based on various levels of laser sampling points and relief variation (low, moderate, and high). Results indicated the existence of a point sampling density threshold that produces little or no additional topographic information when exceeded. A reduced dataset was created using the density thresholds and compared to the original dataset with no major discrepancy. Although variations in relief and soil roughness can lead to different point sampling density requirements, the outcome of this study serves as practical guidance for future field surveys of gully evolution and erosion.

关键词： Ephemeral Gully Ground-Based liDAR Soil Erosion Point Sampling Density Remote Sensing

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