1,482 research outputs found
Geographical and environment-related variations of essential oils in isolated populations of Thymus richardii Pers. in the Mediterranean basin
Composition of essential oils of different populations of Thymus richardii grex of six localities from Bosnia-Herzegovina (Konjic, Borci), Spain (Majorca, Ibiza, Valencia) and Italy (Marettimo, Sicily) were determined by GC/FID and GC/MS. The main constituents in most of the samples were aromatic monoterpenes corresponding to non-phenolic cyclic compounds (p-cymene, gamma-terpinene). The highest monoterpene concentrations were found in the Bosnian samples (70%), and the lowest in samples from the Balearic Islands ( 50%) in samples from Majorca with beta-bisabolene (>40%) being the principal constituent. Discriminant analysis (LDA) shows the differentiation of two chemotypes: A (phenol chemotype), with p-cymene and gamma-terpinene as characteristic compounds and B, with beta-bisabolene and carvacrol, as major and significative compounds. The occurrence of the chemotypes was related to summer positive precipitation and to deep of soils.Llorens, L.; Llorens Molina, JA.; Agnello, S.; Boira Tortajada, H. (2014). Geographical and environment-related variations of essential oils in isolated populations of Thymus richardii Pers. in the Mediterranean basin. Biochemical Systematics and Ecology. 56:246-254. doi:10.1016/j.bse.2014.05.0072462545
Multiple Birthdating Analyses in Adult Neurogenesis: A Line-Up of the Usual Suspects
Analyzing the variation in different subpopulations of newborn neurons is central to the study of adult hippocampal neurogenesis. The acclaimed working hypothesis that different subpopulations of newborn, differentiating neurons could be playing different roles arouses great interest. Therefore, the physiological and quantitative analysis of neuronal subpopulations at different ages is critical to studies of neurogenesis. Such approaches allow cells of different ages to be identified by labeling them according to their probable date of birth. Until very recently, only neurons born at one specific time point could be identified in each experimental animal. However the introduction of different immunohistochemically compatible markers now enables multiple subpopulations of newborn neurons to be analyzed in the same animal as in a line-up, revealing the relationships between these subpopulations in response to specific influences or conditions. This review summarizes the current research carried out using these techniques and outlines some of the key applications
PSS1 Evaluacion Economica De Fototerapia De Banda Angosta O Fotoquimioterapia Para El Tratamiento De Psoriasis Desde La Perspectiva Del Instituto Mexicano Del Seguro SOCIAL
Bilateral Trade and Islamic Sects
This paper explores the effects of religion and Islamic sects on bilateral trade activities by employing an extended version of the gravity model. A stratified sample of 33 countries for the average period 1996-99 is selected. Although gravity models have been extensively used in the literature, to the best of our knowledge, they have neither been used to examine the impact of Islamic sects on bilateral trade nor to estimate religion within a model that incorporates oil-exporting countries, culture, regional trading arrangements, and political freedomessential control variables for the specification of the model. Findings reveal that Muslim majority countries trade less than their Christian, Jewish, Buddhist, or other counterparts. In addition, when disaggregating the Muslim sample into Sunni and Shia sects, results show that Sunni majority countries trade more than their Shiite counterparts. Other results and policy implications are discussed
Black Empowerment in State Legislatures: The Impact of Black Representation on Public Welfare Expenditures in the American States, 1970-1988.
This dissertation presents the findings of research conducted to analyze the impact of black representation in state legislatures on state public welfare expenditures. Data is collected and analyzed for the period of 1970 through 1988. Black representation is operationalized as the percentage of blacks in the total number of legislators of both chambers of each state legislature. Public Welfare expenditures is operationalized as the percentage of the state expenditures classified as public welfare expenditures. Control variables included in the research are region, black population, urbanization, education, income, unemployment, political culture and state welfare employees. A pooled data time series method is employed to analyze the data. A generalized least squares regression model is computed and the results used to test hypotheses concerning the impact of each independent variable on the dependent variable--public welfare expenditures. The major hypothesis is that increases in black representation in state legislatures result in increased levels of public expenditures. It is hypothesized that eleven states in the South that have experienced significant increases in black representation will exhibit a greater impact of black representation on the levels of public welfare expenditures than states outside the South. The findings support the hypothesis that black representation is a significant variable in state welfare expenditures in the total data set. Black representation in the South has a negative impact on state public welfare expenditures. The performance of the region variable supports the theory that there is a significant difference between the eleven states in the South and the non-South states. Urbanization and state welfare employees are significant variables in the regression model. Unemployment is a significant variable but performs in a negative direction, opposite that hypothesized. Education and income perform in negative directions but are not significant. Political culture and black population perform in the hypothesized positive direction but are nonsignificant. The study concludes that black representation is a significant variable in models explaining policy impact and state expenditures
El derecho político de la Segunda República
Estudio preliminar, edición y notas de Sebastián MartínVolumen en el que se editan (dos de ellas por vez primera) las memorias de cátedra de los tres principales constitucionalistas de la II República: Nicolás Pérez Serrano, Eduardo L. Llorens y Francisco Ayala. A través de dichos textos, convenientemente aclarados y ampliados por las notas del editor, los lectores pueden conocer los debates fundamentales que conformaban la disciplina del derecho político en el tiempo de entreguerras. Las memorias van precedidas por un exhaustivo estudio preliminar (pp. IX-CLXXXIX) sobre la fisonomía de aquel saber jurídico. En él se examinan la trayectoria de los profesores que impartían la asignatura; las instituciones en que se investigaba; las revistas, monografías, tratados y artículos en que circulaba; las controversias que la atravesaban; la mentalidad jurídica que de todo ello puede extraerse; y la singular aportación científica de Ayala, Llorens y Pérez Serrano, cuya obra, a juicio del prof. Martín, constituye el destilado más genuino del derecho político de la Segunda República.Este trabajo recibió una ayuda a la investigación de la Fundación Francisco Ayala y el
Ministerio de Cultura. Ha sido elaborado en el marco de los proyectos de investigación
DER2008-03069 y DER2010-21728-C02-0
Enhancement of the indistinguishability of single photon emitters coupled to photonic waveguides
One of the main steps towards large-scale quantum photonics consists of the
integration of single photon sources (SPS) with photonic integrated circuits
(PICs). For that purpose, the PICs should offer an efficient light coupling and
a high preservation of the indistinguishability of photons. Therefore,
optimization of the indistinguishability through waveguide design is especially
relevant. In this work we have developed an analytical model to calculate the
coupling and the indistinguishability of an ideal point-source quantum emitter
coupled to a photonic waveguide depending on source orientation and position.
The model has been numerically evaluated through finite-difference time-domain
(FDTD) simulations showing consistent results. The maximum coupling is achieved
when the emitter is embedded in the center of the waveguide but somewhat
surprisingly the maximum indistinguishability appears when the emitter is
placed at the edge of the waveguide where the electric field is stronger due to
the surface discontinuity
The Gypsy Database (GyDB) of mobile genetic elements: release 2.0
This article introduces the second release of the Gypsy Database of Mobile Genetic Elements (GyDB 2.0): a research project devoted to the evolutionary dynamics of viruses and transposable elements based on their phylogenetic classification (per lineage and protein domain). The Gypsy Database (GyDB) is a long-term project that is continuously progressing, and that owing to the high molecular diversity of mobile elements requires to be completed in several stages. GyDB 2.0 has been powered with a wiki to allow other researchers participate in the project. The current database stage and scope are long terminal repeats (LTR) retroelements and relatives. GyDB 2.0 is an update based on the analysis of Ty3/Gypsy, Retroviridae, Ty1/Copia and Bel/Pao LTR retroelements and the Caulimoviridae pararetroviruses of plants. Among other features, in terms of the aforementioned topics, this update adds: (i) a variety of descriptions and reviews distributed in multiple web pages; (ii) protein-based phylogenies, where phylogenetic levels are assigned to distinct classified elements; (iii) a collection of multiple alignments, lineage-specific hidden Markov models and consensus sequences, called GyDB collection; (iv) updated RefSeq databases and BLAST and HMM servers to facilitate sequence characterization of new LTR retroelement and caulimovirus queries; and (v) a bibliographic server. GyDB 2.0 is available at http://gydb.org
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