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Search Results: 1 - 10 of 464068 matches for " Viviana; Montero-Astúa "
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Incidencia y distribución altitudinal de 13 virus en cultivos de Solanum tuberosum (Solanaceae) en Costa Rica
Vásquez,Viviana; Montero-Astúa,Mauricio; Rivera,Carmen;
Revista de Biología Tropical , 2006,
Abstract: incidence and altitudinal distribution of 13 virus cultures in solanum tuberosum (solanaceae) from costa rica. a survey was conducted in 30 fields located at three different altitudes in cartago, costa rica?s main potato producing area. twenty plants were sampled per farm, for a total of 600 samples with 200 samples per altitude. elisa was used with commercial reagents to independently test for pvx, pvy, pvm, pva, pvs, plrv, pmtv, pamv, pvv, pvt, aplv, apmov and trsv. the presence of the following viruses was determined: pvx (77 %), pamv (62 %), plrv (42 %), trsv (42 %), pvt (39 %), pvv (37 %), pmtv (31 %), pvy (30 %), pvs (19 %), pvm (13 %), pva (8 %), and apmov (8 %). aplv was not detected in any sample. this is the first report in costa rica of the presence of the viruses pmtv, pamv, pvv, pvt and apmov. a high viral incidence in the tuber seed production area as well as a high rate of mixed infections is reported. rev. biol. trop. 54 (4): 1135-1141. epub 2006 dec. 29
Population Genomic Analysis of a Bacterial Plant Pathogen: Novel Insight into the Origin of Pierce's Disease of Grapevine in the U.S.
Leonard Nunney,Xiaoli Yuan,Robin Bromley,John Hartung,Mauricio Montero-Astúa,Lisela Moreira,Beatriz Ortiz,Richard Stouthamer
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0015488
Abstract: Invasive diseases present an increasing problem worldwide; however, genomic techniques are now available to investigate the timing and geographical origin of such introductions. We employed genomic techniques to demonstrate that the bacterial pathogen causing Pierce's disease of grapevine (PD) is not native to the US as previously assumed, but descended from a single genotype introduced from Central America. PD has posed a serious threat to the US wine industry ever since its first outbreak in Anaheim, California in the 1880s and continues to inhibit grape cultivation in a large area of the country. It is caused by infection of xylem vessels by the bacterium Xylella fastidiosa subsp. fastidiosa, a genetically distinct subspecies at least 15,000 years old. We present five independent kinds of evidence that strongly support our invasion hypothesis: 1) a genome-wide lack of genetic variability in X. fastidiosa subsp. fastidiosa found in the US, consistent with a recent common ancestor; 2) evidence for historical allopatry of the North American subspecies X. fastidiosa subsp. multiplex and X. fastidiosa subsp. fastidiosa; 3) evidence that X. fastidiosa subsp. fastidiosa evolved in a more tropical climate than X. fastidiosa subsp. multiplex; 4) much greater genetic variability in the proposed source population in Central America, variation within which the US genotypes are phylogenetically nested; and 5) the circumstantial evidence of importation of known hosts (coffee plants) from Central America directly into southern California just prior to the first known outbreak of the disease. The lack of genetic variation in X. fastidiosa subsp. fastidiosa in the US suggests that preventing additional introductions is important since new genetic variation may undermine PD control measures, or may lead to infection of other crop plants through the creation of novel genotypes via inter-subspecific recombination. In general, geographically mixing of previously isolated subspecies should be avoided.
Distribution extension and sympatric occurrence of Gracilinanus agilis and G. microtarsus (Didelphimorphia, Didelphidae), with cytogenetic notes
Geise, Lena;Astúa, Diego;
Biota Neotropica , 2009, DOI: 10.1590/S1676-06032009000400030
Abstract: gracilinanus microtarsus, from the atlantic forest and g. agilis, widespread in central brazil in the cerrado and in the northeastern caatinga are two small neotropical arboreal opossum species not frequently recorded in simpatry. here we report eight g. agilis specimens from three localities and 17 g. microtarsus, from 10 localities, all in minas gerais, rio de janeiro and bahia states. species proper identification followed diagnostic characters as appearance of dorsum pelage, ocular-mark, ears and tail lengths and size proportion of the posteromedial vacuities in cranium. chromosomes in metaphases of five specimens were obtained for both species. our records extend the previous known geographical distribution of g. microtarsus to chapada diamantina, in bahia state and report the occurrence of both species in simpatry. g. microtarsus, in coastal area, was captured in dense ombrophilous and in semideciduous forests, in deciduous seasonal forest and cerrad?o in chapada diamantina. g. agilis was recorded in gallery forests of cerrado and very green and dense bush formation of caatinga. autosomal complement showed the same diploid and autosomal number already described for both species (2n = 14, na = 24). measurements are according to those given in literature and pelage characteristics were useful for the correct species identification. here we report both g. agilis, described to be endemic to the cerrado/caatinga, in opposite to g. microtarsus, considered to be endemic to atlantic forest occurring in simpatry in two localities of the cerrado. such results indicates that long term trapping effort are necessary to a better definition of species taxonomy, distribution patterns along time and comprehensive understanding how anthropic environmental changes can be interfering in their evolutionary history.
Los materiales Ordovícicos en el arca de Retuerta del Bullaque, sinclinal de Navas de Estena (Ciudad Real)
Montero, A.
Estudios Geologicos , 1989, DOI: 10.3989/egeol.89455-6511
Abstract: This paper deals with the stratigraphy of Ordovician sediments, mainly those of the Llanvirn Dobrotivian (Llandeilo) in the Retuerta del Bullaque area (Ciudad Real). The study is based on that originate from twenty four outcrops distributed throughout the Tristani beds Most exposures are new to scientific literature. Cartography of this area is also presented. Se estudia la estratigrafía de los materiales del Ordovícico, fundamentalmente de los del Llanvirn-Dobrotiviense (LLandeilo), en el área de Retuerta del Bullaque (Ciudad Real), en base a los fósiles de 24 yacimientos, distribuidos en toda la unidad Capas con Tristani , la mayoría de ellos nuevos. Asimismo se realiza una cartografia geológica (E: 1120.000).
Study of SU(3) vortex-like configurations with a new maximal center gauge fixing method
A. Montero
Physics , 1999, DOI: 10.1016/S0370-2693(99)01113-2
Abstract: We present a new way of fixing the gauge to (direct) maximal center gauge in SU(N) Yang-Mills theory and apply this method to SU(3) configurations which are vortex-like. We study the structure of the Z_3 configurations obtained after center-projecting the SU(3) ones.
Hipertensión portal y embarazo
Sáez Cantero,Viviana; Pérez Hernández,María Teresa; Daudinot Cos,Carlos E; Molina Pérez,Carmen Rosa; Miranda Albert,Jaime; Montero Martínez,Francisco; Peraza Torres,María;
Revista Cubana de Obstetricia y Ginecolog?-a , 2009,
Abstract: pregnancy with associated portal hypertension is a complex clinical situation for obstetrician, and for the multidisciplinary staff responsible for its care. during the gravidism state there is an increment in portal flow as consequence of the developed hypervolemia state, and it contributes to a greater portal pressure transmitted to collateral veins increasing the bleeding risk of esophageal varices in these patients. we present the case of a pregnant woman aged 20 carrier of pre-hepatic portal hypertension which after its multidisciplinary management had a non-complicated pregnancy and labor. we made a review of literature available on this matter.
Contextual control over expression of fear is affected by cortisol
Vanessa A. van Ast,Bram Vervliet,Merel Kindt
Frontiers in Behavioral Neuroscience , 2012, DOI: 10.3389/fnbeh.2012.00067
Abstract: At the core of anxiety disorders is the inability to use contextual information to modulate behavioral responses to potentially threatening events. Models of the pathogenesis of anxiety disorders incorporate stress and concomitant stress hormones as important vulnerability factors, while others emphasize sex as an important factor. However, translational basic research has not yet investigated the effects of stress hormones and sex on the ability to use contextual information to modulate responses to threat. Therefore, the purpose of the present study was threefold: first, we aimed at developing an experimental paradigm specifically capable of capturing contextual modulation of the expression of fear. Second, we tested whether cortisol would alter the contextualization of fear expression. Third, we aimed at assessing whether alterations in contextualization due to cortisol were different for men and women. Healthy participants (n = 42) received placebo or hydrocortisone (20 mg) prior to undergoing a newly developed differential contextual fear-conditioning paradigm. The results indicated that people rapidly acquire differential contextual modulation of the expression of fear, as measured by fear potentiated startle (FPS) and skin conductance responses (SCR). In addition, cortisol impaired the contextualization of fear expression leading to increased fear generalization on FPS data in women. The opposite pattern was found in men. Finally, as assessed by SCR, cortisol impaired differential conditioning in men. The results are in line with models suggesting heightened vulnerability in women for developing anxiety disorders after stressful events.
Uma proposta de avalia??o integrada de risco do uso de agrotóxicos no estado do Amazonas, Brasil
Waichman, Andréa Viviana;
Acta Amazonica , 2008, DOI: 10.1590/S0044-59672008000100006
Abstract: during the last 30 years, the increase of the human population in the amazon introduced the need for additional food production and caused the state government to implement programs to increase and improve agricultural production. the production of nontraditional crops introduced several problems unknown to traditional farmers, since they are not well adapted to tropical conditions. their susceptibility to insects, fungi and other plagues, and the competition with native vegetation forced farmers to use pesticides intensively. amazonian farmers were not adequately prepared for the use of this new technology and they ignored the risk of pesticides to human health and the environment. farmers do not use protective clothing or equipment because they are expensive and not suitable for a tropical climate in which they prove to be very uncomfortable. the lack in training and poor knowledge of pesticide hazards contribute to careless handling during preparation, application and disposal of empty packages. under such circumstances, exposure of farmers, their families, consumers and the environment is high. as a first step to solve this problem, an integrated risk assessment is proposed. the three stages of the process, problem formulation, exposure assessment, and risk characterization are explained. training and information programs are part of the strategies risk-reduction in order to build up environmentally sustainable agriculture.
Dinheiro, poder e sexo
Zelizer, Viviana A.;
Cadernos Pagu , 2009, DOI: 10.1590/S0104-83332009000100005
Abstract: widespread beliefs that money corrupts intimacy block our ability to describe and explain how money, power, and sex actually interact. the opposite belief - that sex operates like an ordinary market commodity - serves description and explanation no better. the intersection of sex, money, and power, does indeed generate confusion and conflict, but that is precisely because participants are simultaneously negotiating delicate, consequential, interpersonal relations and marking differences between those relations and others with which they could easily and dangerously be confused. in everyday social life, people deal with these difficulties by relying on a set of practices we can call good matches.
Estudio del discurso de una madre que denuncia abuso sexual intrafamiliar e intenta dominar la mente del otro
Torres,María Viviana;
Subjetividad y procesos cognitivos , 2010,
Abstract: this study is based on the results of the exploratory research concerning mothers who reported domestic sexual abuse of their children, whose speech was analyzed using the david liberman ((dla) algorithm method. it focuses on the analyses of the findings of the study of the narrations, on a particular type of lies and displays their purpose -to shape thoughts and control the minds of others- as well as on the salient features of the subjectivity of mothers, in terms of drives and defenses. the study consists of three parts. in the first part, the author describes the theoretical framework and method -freudian theory of sexuality as category network and the dla regarding its operationalization. in the second part, the case is presented along with its meticulous analysis with the method. finally the conclusions are offered. the latter provide an answer to how inter-subjectivity is displayed and the impact it has on the other, and come to a decision as to what points of fixation subtend this type of lies.
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