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Worker laying in leafcutter ant Acromyrmex subterraneus brunneus （formicidae, Attini）

Insect Science 2007年第2期14卷 157-163页

作者： ROBERTO S. CAMARGO luiz C. fORTI JULIANE f. S. LOPES NEWTON C. NORONHA ANGELO L. T. OTTATI Departamento de Producāo Vegetal FCA/UNESP Botucatu SP Campus Universitário Paulo VI Sāo Luis MA Brazil. Comportamento e Biologia Animal Instituto de Ciencias Biológicas Universidade Federal de Juiz de Fora Campus Universitário Martelos Juiz de Fora MG Campus Universitário Paulo VI Sāo Luis MA Brazil. Departamento de Entomologia Fitopatologia e Zoologia Agricola Escola Superior de Agricultura 'Luiz de Queiroz' Universidade de Sao Paulo Piracicaba SP Campus Universitário Paulo VI Sāo Luis MA Brazil. Departamento de fitotecnia e fitossanidade Universidade Estadual do Maranhāo Centro de Ciencias Agrenias Campus Universitário Paulo VI Sāo Luis MA Brazil.

We studied the process of offspring production in queenless colonies of Acromyrmex subterraneus brunneus, and particularly evaluated the ovary development of workers as a function of their age. for this, subcolonies were set up and evaluated at different periods of isolation from the queen （2, 4 and 6 months）, besides individually labeled age groups. The subcolonies were assessed according to offspring production and ovaries containing oocytes or not. The evaluations showed worker oviposition and development of males originating from worker-laid eggs. At 2 months＇ absence of the queen, eggs and larvae were found, with eggs in a higher proportion than larvae. After 4 months, the proportion of eggs had reduced while larvae had increased, and a pupa was found in one subcolony. At 6 months, besides a higher share of larvae, one pupa and one adult male were found. Dissection of workers revealed ovaries containing oocytes during the periods of evaluation. Only a group of medium-sized and large workers, 23.3%, 20.9% and 37.5% of the population from each period assessed in queenless subcolonies respectively, presented developed oocytes in the ovary. The same was observed in colonies with a queen, with 17.6%, 19.6% and 7.8% of the group of dissected workers from each time period, respectively. With respect to worker age, we observed by dissection of the ovary, that the greatest percentage of individuals with ovarioles containing oocytes occurred at 45 days （6 weeks） up to 90 days （12 weeks）. These results probably are associated with the workers reproduction and the laying of trophic and reproductive eggs in colonies with and without a queen; these eggs have distinct functions in each situation.

关键词： leafcutter ant queenless ant colonies reproduction conflict worker laying,worker reproduction

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Zeta potential measurement on lithium lanthanum titanate nanoceramics

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Particuology 2016年第1期14卷 69-72页

作者： Carlos Ricardo Milian Pila Eduardo Perez Cappe Yodalgis Mosqueda Laffita Oswaldo luiz Alves Institute of Materials Science and Technology (IMRE) Havana University Havana CP 10400 Cuba Solid state Chemistry Laboratory Institute of Chemistry Campinas University Campinas CP 13083-970 SP Brazil

The zeta potential, isoelectric point, and agglomeration of ***3 （LLTO） nanoparticles dispersed in aqueous media at different ionic strengths have been studied. The zeta potential was determined from electrophoretic mobility measurements, according to Smoluchowski＇s equation, for Li0.5La0.5TiO3 suspen- sions in NaCl and KCI electrolytes with ionic strengths of 1, 10, and 100 mmol/dm3. The isoelectric point （IEP）, zeta potential （ζ）, and the agglomeration were shown to strongly depend on the ionic strength of the Li0.5La0.5TiO3 aqueous colloidal suspension in both NaCI and KCI electrolytes, which allows the deter- mination of the effects of environmental conditions for ***3 manipulation in aqueous colloidal systems. The suspensions of Li0.5La0.5TiO3 nanoparticles reach the IEP in the pH range 0f3-5. The （ of Li0.5La0.5TiO3 nanoparticles varied from positive to negative values with a pH increase, which allows for the control of the surface charge depending on the purpose. The pH range of 7-g and an ionic strength ≤1 mmol/dm3 are recommended as the most suitable conditions for both the LLTO colloidal shaping techniques application and the LLTO-based nanocomposite formation.

关键词： Titanate Nanoparticles Zeta potential Colloidal suspension

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The assessment of climatic,environmental,and socioeconomic aspects of the Brazilian Cerrado

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Ecological Processes 2023年第1期12卷 274-285页

作者： Washington luiz félix Correia filho Joséfrancisco de Oliveira-Júnior Dimas de Barros Santiago Hazem Ghassan Abdo Hussein Almohamad Ahmed Abdullah Al Dughairi Carlos Antonio da Silva Junior Postgraduate Program in Environmentrics(PPGAmb) Institute of MathematicsStatisticsand Physics(IMEF)Federal University of Rio Grande(FURG)Rio GrandeRio Grande do Sul 96203-900Brazil Institute of Atmospheric Sciences(ICAT) Federal University of Alagoas(UFAL)MaceióAlagoas 57072-260Brazil Postgraduate Program in Biosystems Engineering(PGEB) Federal Fluminense University(UFF)NiteróiRio de Janeiro 24220-900Brazil Postgraduate Program in Meteorology Unidade Acadêmica de Ciências Atmosféricas(UACA)Federal University of Campina Grande(UFCG)Campina GrandeParaíba 58429-140Brazil Geography Department Faculty of Arts and HumanitiesTartous UniversityTartousSyria Geography Department Faculty of Arts and HumanitiesDamascus UniversityDamascusSyria Geography Department Faculty of Arts and HumanitiesTishreen UniversityLat-takiaSyria Department of Geography College of Arabic Language and Social StudiesQassim UniversityBuraydah 51452Saudi Arabia Departamento de Geografia State University of Mato Grosso(UNEMAT)SinopMato Grosso 78555-000Brazil

Background The Cerrado is the most biodiverse savanna and maintains other *** of its significance,this paper evaluated the Brazilian Cerrado’s climatic,environmental,and socioeconomic aspects using remote sensing data and spatial statistics(correlation analysis and principal components analysis—PCA).following the measures of sample adequacy(MSA)and Kaiser–Meyer–Olkin(KMO)tests,seventeen variables were *** The MSA revealed that the dataset had a good quality(0.76),and nine variables were selected:elevation,evapotranspiration,active fires,Human Development Index(HDI),land use and land cover(LULC;shrubland and cropland/rainfed),rainfall(spring and autumn),and *** correlation matrix indicated a positive(negative)association between HDI and autumn rainfall(HDI and active fires)with a value of 0.77(-0.55).The PCA results determined which three principal components(PC)were adequate for extracting spatial patterns,accounting for 68.02%of the total variance with respective values of 38.59%,16.89%,and 12.5%.Due to economic development and agribusiness,Cerrado’s northern(central,western,and southern)areas had negative(positive)score HDI values,as shown in ***(rainfall—spring and fall)and environmental(cropland/rainfed and shrubland)aspects dominated the PC2,with negative scores in northern and western portions due to the transition zone between Amazon and Cerrado biomes caused by rainfall *** the other hand,environmental aspects(LULC-shrubland and elevation)influenced the PC3;areas with high altitudes(>500 m)received a higher *** Agricultural expansion substantially affected LULC,leading to deforestation-caused suppression of native vegetation.

关键词： Environment Agribusiness Active fire Human Development Index Land use and land cover

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Weighted single-step GWAS and RNA sequencing reveals key candidate genes associated with physiological indicators of heat stress in Holstein cattle

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Journal of Animal Science and Biotechnology 2022年第6期13卷 1714-1726页

作者： Hanpeng Luo Lirong Hu luiz f.Brito Jinhuan Dou Abdul Sammad Yao Chang Longgang Ma Gang Guo Lin Liu Liwei Zhai Qing Xu Yachun Wang Laboratory of Animal Genetics Breeding and ReproductionMinistry of Agriculture of ChinaNational Engineering Laboratory of Animal BreedingCollege of Animal Science andTechnologyChina Agricultural UniversityNo.2Yuanmingyuanxi RoadHaidian DistrictBeijing 100193China Department of Animal Sciences Purdue UniversityWest LafayetteIN 47907USA College of Animal Science andTechnology Beijing University of AgricultureBeijing 100096China College of Animal Science Xinjiang Agricultural UniversityUrumqi 830052China Beijing Sunlon Livestock Development Company Limited Beijing 100029China Beijing Dairy Cattle Center Beijing 100192China College of Life Sciences and Bioengineering Beijing Jiaotong UniversityBeijing 100044China

Background: The study of molecular processes regulating heat stress response in dairy cattle is paramount for developing mitigation strategies to improve heat tolerance and animal welfare. Therefore, we aimed to identify quantitative trait loci(QTL) regions associated with three physiological indicators of heat stress response in Holstein cattle, including rectal temperature(RT), respiration rate score(RS), and drooling score(DS). We estimated genetic parameters for all three traits. Subsequently, a weighted single-step genome-wide association study(WssGWAS) was performed based on 3200 genotypes, 151,486 phenotypic records, and 38,101 animals in the pedigree file. The candidate genes located within the identified QTL regions were further investigated through RNA sequencing(RNA-seq) analyses of blood samples for four cows collected in April(non-heat stress group) and four cows collected in July(heat stress group).Results: The heritability estimates for RT, RS, and DS were 0.06, 0.04, and 0.03, respectively. fourteen, 19, and 20 genomic regions explained 2.94%, 3.74%, and 4.01% of the total additive genetic variance of RT, RS, and DS, respectively. Most of these genomic regions are located in the Bos taurus autosome(BTA) BTA3, BTA6, BTA8, BTA12, BTA14, BTA21, and BTA24. No genomic regions overlapped between the three indicators of heat stress, indicating the polygenic nature of heat tolerance and the complementary mechanisms involved in heat stress response. for the RNA-seq analyses, 2627 genes were significantly upregulated and 369 downregulated in the heat stress group in comparison to the control group. When integrating the WssGWAS, RNA-seq results, and existing literature, the key candidate genes associated with physiological indicators of heat stress in Holstein cattle are: PMAIP1, SBK1, TMEM33, GATB, CHORDC1, RTN4IP1, and ***: Physiological indicators of heat stress are heritable and can be improved through direct selection. fifty-three QTL regions

关键词： Climatic resilience Dairy cattle QTL mapping RNA sequencing WssGWAS

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Prenatal and pubertal testosterone exposure imprint permanent modifications in the prostate that predispose to the development of lesions in old Mongolian gerbils

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Asian Journal of Andrology 2017年第2期19卷 160-167页

作者： Manoel f Biancardi Ana PS Perez Cassia RS Caires luiz R falleiros Jr Rejane M Goes Patricia SL Vilamaior Diogenes R freitas Jr fernanda CA Santos Sebastiao R Taboga Department of Structural and functional State University of Campinas Av. Bertrand Russel s/n Campinas Sao Paulo 13084864 Brazil 2Department of Histology Embryology and Cell BiologyFederal University of Goias Samambaia II Goiania Goias 74001970 Brazil University Estadual Paulista - UNESP Department of Biology Laboratory of Microscopy and Microanalysis Rua Cristovao Colombo 2265 Sao Jose do Rio Preto Sao Paulo 15054000 Brazil Medical School Federal University of Goias Colemar Natal e Silva Goiania Goias 74001970 Brazil

The prostate is an accessory sex gland that develops under precise androgenic control. It is known that hormonal imbalance may disrupt its development predisposing this gland to develop diseases during aging. Although the hypothesis regarding earlier origins of prostate diseases was proposed many years ago, the mechanisms underlying this complex phenomenon are poorly understood. Therefore, the aim of this study was to evaluate the prostates of old male gerbils exposed to testosterone during intrauterine and postnatal life using morphological, biometrical, stereological, Kariometric, immunohistochemical, and immunofluorescence analyses. Our findings demonstrate that prenatal and pubertal exposure to testosterone increases the susceptibility to the development of prostate diseases during aging. The presence of a more proliferative gland associated with foci of adenomatous hyperplasia in animals exposed to testosterone during the prenatal and pubertal phase show that the utero life and the pubertal period are important phases for prostatic morphophysiology establishment, which is a determinant for the health of the gland during aging. Therefore, these findings reinforce the idea that prostate disease may result from hormonal disruptions in early events during prostate development, which imprint permanently on the gland predisposing it to develop lesions in later stages of life.

关键词： adenomatous hyperplasia endocrine-disrupting chemicals gerbil prostate development testosterone

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短氟碳链含氟硅烷偶联剂及其疏水涂层的构建

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精细化工 2020年第2期37卷 412-419,432页

作者：金大钺张先伟范宏 bittencourt Carla Dubois Philippe 浙江大学化学工程与生物工程学院化学工程联合国家重点实验室浙江杭州310027 蒙斯大学材料与聚合物创新研究中心(CIRMAP)比利时蒙斯B-7000

以三氟丙基甲基环三硅氧烷(D3f)、二甲基氯硅烷、甲基二氯硅烷、乙烯基三甲氧基硅烷(VTMS)为主要原料,通过阴离子开环聚合和硅氢加成反应合成了一系列短氟碳链含氟硅烷偶联剂。载玻片表面经纳米二氧化硅溶胶涂膜和硅烷偶联剂表面修饰得... 详细信息

以三氟丙基甲基环三硅氧烷(D3f)、二甲基氯硅烷、甲基二氯硅烷、乙烯基三甲氧基硅烷(VTMS)为主要原料,通过阴离子开环聚合和硅氢加成反应合成了一系列短氟碳链含氟硅烷偶联剂。载玻片表面经纳米二氧化硅溶胶涂膜和硅烷偶联剂表面修饰得到疏水涂层。探究了不同硅烷偶联剂对于涂层疏水性、附着力、硬度、透过率等性能的影响。结果表明,同类型含氟硅烷偶联剂中氟含量越大,其修饰的涂层接触角越大;相似相对分子质量及氟含量情况下,直链型含氟硅烷偶联剂修饰的涂层疏水性优于支链型修饰的涂层。经含氟硅烷偶联剂修饰的疏水涂层中,接触角最大的是由聚合度为9的支链型含氟硅烷偶联剂(Df3)修饰的涂层,可达141.6°。疏水涂层的附着力均达1级,硬度均达H,可见光透过率高于82.9%,具有良好的自清洁性能。

关键词：含氟硅烷偶联剂疏水涂层溶胶凝胶法自清洁建筑用化学品

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Can rainfall seasonality trigger soil water repellency in a tropical riparian forest?

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Journal of forestry Research 2023年第3期34卷 773-780页

作者： Gleicon Queiroz de Brito Johnny Rodrigues de Melo Murta Sérgio fernandes Mendonca filho luiz felippe Salemi Núcleo de Estudos e Pesquisas Ambientais e Limnológicas(NEPAL) Faculdade UnB de Planaltina(FUP)Universidade de Brasília(UnB)DFVila Nossa Senhora de FátimaÁrea Universitária 1Planaltina 73345-010Brazil

Though riparian areas generally have a shallow water table and higher soil moisture compared to up slope areas,climatic seasonality may trigger water repellency in tropical riparian forests,which,if persistent,could negatively affect essential ecosystem functions related to water resources protection such as reduced overland-flow,sediment transport,and nutrient *** objective of this study was to answer the following:can tropical riparian forests develop water repellency?If so,does water repellency affect infiltration on a seasonal basis?for this,water repellency and infiltration were measured in a grid of 72points during a dry and a wet month of a tropical riparian forest with a shallow water table in a region with highly marked climatic *** repellency and infiltration were significantly different between the wet and dry *** repellency affected negatively infiltration in the dry month,its effect in the wet month was *** a result,a higher infiltration capacity was observed over the wet *** research has claimed that the development and persistence of repellency in soils could promote other hydrological processes such as overland *** findings shown here demonstrate that such phenomenon does not persist longer than the dry season.

关键词： Hydrophobicity Gallery forest Aquifer recharge Climate change Erosion

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Adipose tissue,systematic inflammation,and neurodegenerative diseases

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Neural Regeneration Research 2023年第1期18卷 38-46页

作者： Ana Paula de A.Boleti Pedro Henrique de O.Cardoso Breno Emanuel f.frihling Patrícia Souza e Silva luiz filipe R.Nde Moraes Ludovico Migliolo S-Inova Biotech Programa de Pós-Graduação em BiotecnologiaUniversidade Católica Dom BoscoCampo GrandeMSBrazil Programa de Pós-Graduação em Biologia Celular e Molecular Programa de Pós-Graduação em BioquímicaUniversidade Federal do Rio Grande do NorteNatalBrazil

Obesity is associated with several diseases,including mental *** tissue is distributed around the internal organs,acting in the regulation of metabolism by storing and releasing fatty acids and adipokine in the *** nutritional intake results in hypertrophy and proliferation of adipocytes,leading to local hypoxia in adipose tissue and changes in these adipokine *** leads to the recruitment of immune cells to adipose tissue and the release of pro-inflammatory *** presence of high levels of free fatty acids and inflammatory molecules interfere with intracellular insulin signaling,which can generate a neuroinflammatory *** this review,we provide an up-to-date discussion of how excessive obesity can lead to possible cognitive *** also address the idea that obesity-associated systemic inflammation leads to neuroinflammation in the brain,particularly the hypothalamus and hippocampus,and that this is partially responsible for these negative cognitive *** addition,we discuss some clinical models and animal studies for obesity and clarify the mechanism of action of anti-obesity drugs in the central nervous system.

关键词： adiposity anti-obesity drugs hypothalamic inflammation metabolic disease neurodegenerative disease neuroinflammation

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Sward Structural Characteristics and Performance of Beef Heifers Reared under Rotational Grazing Management on Campos Grassland

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American Journal of Plant Sciences 2014年第7期5卷 1020-1029页

作者： Cezar Wancura Barbieri fernando luiz f. de Quadros felipe Jochims émerson Mendes Soares Leandro bittencourt de Oliveira Régis Maximiliano R. Carvalho Gabriela Machado Dutra felipe Xavier de Lima franciele Gusatto Natural Grassland Ecology Research Group (LEPAN-UfSM) Universidade Federal de Santa Maria Animal Science Department Santa Maria Brazil

This study aimed to evaluate the effect of two rest intervals on structural sward characteristics and productive performance of beef heifers reared on Campos grassland managed on rotational grazing. The treatments were two intervals between grazing of 375 and 750 DD (degree days), based on thermal cumulative sum for leaf expansion of native grasses belonging to two functional groups. The experimental design was a randomized complete block design with two treatments and three replications. The tested animals were beef heifers with initial age of 12 months and average weight of 185.2 ± 17.4 kg. Measures in the pasture were: herbage mass, mass of green leaf blades, stem mass, dead material mass and green leaf allowance. The 750 DD rest interval presented higher herbage mass (24%), higher green herbage mass and 19% more leaves in the canopy. This rest interval also presents a high proportion of dead material and stems in the sward structure. In the other way, the 375 DD rest interval presents better chemical characteristics, with 20% more crude protein in the hand plucking samples. Heifers’ dry matter intake was similar between the rest intervals (2.04% of live weight) and the bite mass was also similar (0.22 g DM per bite) but the animal performance was higher in the 375 DD rest interval. The stocking density showed similarity between treatments with an average of 875 kg/LW/ha. The live weight gain per area was higher in 40 kg/LW/ha (P = 0.117) for 375 DD rest interval, reaching 251 kg/LW/ha produced over the 149 experimental days. Based on these results, we can conclude that the treatment of shortest interval between defoliation gave the highest gain individual animals in warm seasons.

关键词： Average Daily Gain Duration of Leaf Expansion Herbage Mass Rotational Grazing Stocking Rate

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Effects of aeration on the suspended matter from a tropical and eutrophic estuary

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Journal of Environmental Sciences 2019年第12期31卷 175-186页

作者： Natascha Krepsky Maria das Gracas S.Bispo luiz f.fontana frederico S.da Silva Jodo P.M.Torres Olaf Malm Cleverson G.Silva Mirian A.C.Crapez Laboratory of Marine Geology Fluminense Federal UniuersityAue.Gen.Milton Tauares de Souza s/n°-Gragoata24210-346 NiterdiRJBrazil Radioisotopes Laboratory Eduardo Penna franca Biophysics Institute Carlos Chagas FilhoFederal University of Rio de JaneiroAu.Carlos Chagas Filho373 CCS-Bl.G21941-902 Rio de JaneiroRJBrazil Marine Biology Department Fluminense Federal UniversityR.Mario Santos Bragas/nNiteroi24.020-141 NiteroiRJBrazil

A comprehensive understanding of the complex biogeochemical interactions between organic matter and persistent contaminants in the suspended matter is vital for ecoefficient estuary ***,little is known regarding aeration effects in suspended particulate ***,this study aimed to investigate the effects of aeration on the suspended matter from a Tropical and Eutrophic estuarine *** water with 60 g/L of suspended particulate matter(SPM)was collected from Guanabara Bay,Rio de Janeiro,Brazil,transferred to experimental boxes and aerated for 61 *** aggregates monitoring included abiotic variables measurements and,determination of total organic matter(TOM),biopolymers composition,bacterial activity,trace metals,and polycyclic aromatic hydrocarbons(PAHs)*** aeration enhanced dissolved oxygen(DO)concentration and the redox potential(Eh).However,from days 0 to 61 the predominant bacterial activities were denitrification and *** transport system activity increased after day 10,and aerobic activity was detected after day *** summary,aeration increased aerobic bacterial activity,lipids(LIP)and trace metal concentrations,although diminished protein/carbohydrate ratio and PAH *** metals concentration(Ni,Pb,Cu,Cr,Mn,and fe)were the highest on day 19 when the p H was *** presented toxic values(Cu>20.0μg/g).The p H showed a strong negative correlation with Eh(r=-0.94;pf toxic trace metals is unsafe for ***,managers must be aware of the environmental and biological risks of introducing the aeration technique into a eutrophic marine environment.

关键词： Mixed-pollution Remediation Acidification Esterases enzymes Biopolymer

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