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Search Results: 1 - 10 of 210628 matches for " Raúl;Quispe "
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Trabajo de marcaza
Raúl Beto Gómez Quispe
Anthropologica , 1985,
Abstract: El artículo no presenta resumen.
Modernization, Sexual Risk-Taking, and Gynecological Morbidity among Bolivian Forager-Horticulturalists
Jonathan Stieglitz, Aaron D. Blackwell, Raúl Quispe Gutierrez, Edhitt Cortez Linares, Michael Gurven, Hillard Kaplan
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0050384
Abstract: Sexual risk-taking and reproductive morbidity are common among rapidly modernizing populations with little material wealth, limited schooling, minimal access to modern contraception and healthcare, and gendered inequalities in resource access that limit female autonomy in cohabiting relationships. Few studies have examined how modernization influences sexual risk-taking and reproductive health early in demographic transition. Tsimane are a natural fertility population of Bolivian forager-farmers; they are not urbanized, reside in small-scale villages, and lack public health infrastructure. We test whether modernization is associated with greater sexual risk-taking, report prevalence of gynecological morbidity (GM), and test whether modernization, sexual risk-taking and parity are associated with greater risk of GM. Data were collected from 2002–2010 using interviews, clinical exams, and laboratory analysis of cervical cells. We find opposing effects of modernization on both sexual risk-taking and risk of GM. Residential proximity to town and Spanish fluency are associated with greater likelihood of men’s infidelity, and with number of lifetime sexual partners for men and women. However, for women, literacy is associated with delayed sexual debut after controlling for town proximity. Fifty-five percent of women present at least one clinical indicator of GM (n = 377); 48% present inflammation of cervical cells, and in 11% the inflammation results from sexually transmitted infection (trichomoniasis). Despite having easier access to modern healthcare, women residing near town experience greater likelihood of cervical inflammation and trichomoniasis relative to women in remote villages; women who are fluent in Spanish are also more likely to present trichomoniasis relative to women with moderate or no fluency. However, literate women experience lower likelihood of trichomoniasis. Parity has no effect on risk of GM. Our results suggest a net increase in risk of reproductive morbidity among rapidly modernizing, resource-stressed populations.
Abiotic modulators of Podocnemis unifilis (Testudines: Podocnemididae) abundances in the Peruvian Amazon
Norris, Darren;Pitman, Nigel C.A.;Martínez Gonzalez, Jerry;Torres, Eriberto;Pinto, Fernando;Collado, Hernán;Concha, Wilberth;Thupa, Raúl;Quispe, Edwin;Pérez, Jorge;Flores del Castillo, Juan Carlos;
Zoologia (Curitiba) , 2011, DOI: 10.1590/S1984-46702011000300008
Abstract: previous studies have demonstrated that river-based surveys can provide an inexpensive source of information for neotropical zoologists, yet little information is available to inform the application of this technique for the long term monitoring of neotropical turtle species. we aimed to fill this gap by presenting an assessment of data collected during 333 river surveys over 50 months along rivers in a newly protected area in the peruvian amazon. a total of 14,138 basking podocnemis unifilis troschel, 1848 were recorded during 13,510 km of river-based surveys. we used generalized additive models (gams) to explore the influence of a series of abiotic and seasonal variables on the recorded abundances at two temporal scales: monthly and per trip. our analysis revealed that there was a significant increase in turtle abundances during the study period and we also found a significant seasonal periodicity in monthly abundances. abiotic factors strongly influenced trip level abundances, with more individuals per kilometer recorded during sunny days in the dry season, with temperatures between 25 and 30°c. the results demonstrate that turtle populations are increasing following the establishment of the protected area and that river-based surveys are likely to be more effective when carried out within a limited set of key abiotic conditions.
Fields of moduli and fields of definition of odd signature curves
Michela Artebani,Saúl Quispe
Mathematics , 2011,
Abstract: Let $X$ be a smooth projective algebraic curve of genus $g\geq 2$ defined over a field $K$. We show that $X$ can be defined over its field of moduli if it has odd signature, i.e. if the signature of the covering $X\to X/\Aut(X)$ is of type $(0;c_1,...,c_k)$, where some $c_i$ appears an odd number of times. This result is applied to $q$-gonal curves and to plane quartics. For $q$-gonal curves, we prove that non-normal $q$-gonal curves can be defined over their field of moduli and we construct examples of normal $q$-gonal curves with field of moduli $\mathbb{R}$ that can not be defined over $\mathbb{R}$. For plane quartics, we prove that they can be defined over their field of moduli if the automorphism group is not isomorphic to either $C_2$ or $C_2\times C_2$.
Moore-Penrose Inverse and Semilinear Equations  [PDF]
Hugo Leiva, Raúl Manzanilla
Advances in Linear Algebra & Matrix Theory (ALAMT) , 2018, DOI: 10.4236/alamt.2018.81002
Abstract: In this paper, we study the existence of solutions for the semilinear equation \"\", where A is a \"\", \"\", \"\" and \"\" is a nonlinear continuous function. Assuming that the Moore-Penrose inverse AT(AAT)-1?exists (A denotes the transposed matrix of A) which is true whenever the determinant of the \"\" matrix AAT is different than zero, and the following condition on the nonlinear term \"\" satisfied \"\". We prove that the semilinear equation has solutions for all\"\". Moreover, these solutions can be found from the following fixed point relation \"\".
Structure of the Chloroplast Ribosome: Novel Domains for Translation Regulation
Andrea L. Manuell,Joel Quispe,Stephen P. Mayfield
PLOS Biology , 2012, DOI: 10.1371/journal.pbio.0050209
Abstract: Gene expression in chloroplasts is controlled primarily through the regulation of translation. This regulation allows coordinate expression between the plastid and nuclear genomes, and is responsive to environmental conditions. Despite common ancestry with bacterial translation, chloroplast translation is more complex and involves positive regulatory mRNA elements and a host of requisite protein translation factors that do not have counterparts in bacteria. Previous proteomic analyses of the chloroplast ribosome identified a significant number of chloroplast-unique ribosomal proteins that expand upon a basic bacterial 70S-like composition. In this study, cryo-electron microscopy and single-particle reconstruction were used to calculate the structure of the chloroplast ribosome to a resolution of 15.5 ?. Chloroplast-unique proteins are visualized as novel structural additions to a basic bacterial ribosome core. These structures are located at optimal positions on the chloroplast ribosome for interaction with mRNAs during translation initiation. Visualization of these chloroplast-unique structures on the ribosome, combined with mRNA cross-linking, allows us to propose a model for translation initiation in chloroplasts in which chloroplast-unique ribosomal proteins interact with plastid-specific translation factors and RNA elements to facilitate regulated translation of chloroplast mRNAs.
Structure of the Chloroplast Ribosome: Novel Domains for Translation Regulation
Andrea L Manuell,Joel Quispe,Stephen P Mayfield
PLOS Biology , 2007, DOI: 10.1371/journal.pbio.0050209
Abstract: Gene expression in chloroplasts is controlled primarily through the regulation of translation. This regulation allows coordinate expression between the plastid and nuclear genomes, and is responsive to environmental conditions. Despite common ancestry with bacterial translation, chloroplast translation is more complex and involves positive regulatory mRNA elements and a host of requisite protein translation factors that do not have counterparts in bacteria. Previous proteomic analyses of the chloroplast ribosome identified a significant number of chloroplast-unique ribosomal proteins that expand upon a basic bacterial 70S-like composition. In this study, cryo-electron microscopy and single-particle reconstruction were used to calculate the structure of the chloroplast ribosome to a resolution of 15.5 ?. Chloroplast-unique proteins are visualized as novel structural additions to a basic bacterial ribosome core. These structures are located at optimal positions on the chloroplast ribosome for interaction with mRNAs during translation initiation. Visualization of these chloroplast-unique structures on the ribosome, combined with mRNA cross-linking, allows us to propose a model for translation initiation in chloroplasts in which chloroplast-unique ribosomal proteins interact with plastid-specific translation factors and RNA elements to facilitate regulated translation of chloroplast mRNAs.
Isogenous decomposition of the Jacobian of generalized Fermat curves
Mariela Carvacho,Rubén A. Hidalgo,Saúl Quispe
Mathematics , 2015,
Abstract: A closed Riemann surface $S$ is called a generalized Fermat curve of type $(p,n)$, where $p,n \geq 2$ are integers, if it admits a group $H \cong {\mathbb Z}_{p}^{n}$ of conformal automorphisms so that $S/H$ is an orbifold of genus zero with exactly $n+1$ cone points, each one of order $p$. It is known that $S$ is a fiber product of $(n-1)$ classical Fermat curves of degree $p$ and, for $(p-1)(n-1)>2$, that it is a non-hyperelliptic Riemann surface. In this paper, assuming $p$ to be a prime integer, we provide a decomposition, up to isogeny, of the Jacobian variety $JS$ as a product of Jacobian varieties of certain cyclic $p$-gonal curves. Explicit equations for these $p$-gonal curves are provided in terms of the equations for $S$. As a consequence of this decomposition, we are able to provide explicit positive-dimensional families of closed Riemann surfaces whose Jacobian variety is isogenous to the product of elliptic curves.
Interactions between a Root Knot Nematode (Meloidogyne exigua) and Arbuscular Mycorrhizae in Coffee Plant Development (Coffea arabica)  [PDF]
Raúl Alban, Ricardo Guerrero, Marcia Toro
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.47A2003
Abstract: This paper focuses on parasitic root knot nematodes (Meloidogyne exigua) and how to decrease their pathogenic effect on coffee plants (Coffea arabica), by examining the behaviour of and the interactions between nematodes, coffee plant and arbuscular mycorrhizae (AM). The experiment was carried out at the seedling stage, with six (6) treatments (plants with M. exigua, plants with arbuscular mycorrhizae, plants with both organisms, and the same time, first mycorrhizae plants, then nematodes were inoculated and vice versa). After 5 months the measured variables were: dry biomass (roots and shoot), nematode knots caused by M. exigua in root, nematode juvenile (J2) found in 100.0 g of soil, and mycorrhizal percentage. Plant nutrients (P and N) contents were analysed. Significant differences were found in all the variables, but concentration N content in plants. Plants with mycorrhizae and plants with mycorrhizae and then inoculated with nematodes have the same behaviour. Control plants and plants with nematode and then inoculated with mycorrhizae behave similarly. It is thought that arbuscular mycorrhizae are formed before the nematode infestation, allowing coffee plants to regain the energy lost by the parasitic interaction. AM may help coffee plants with lignifications of the plant cell wall cuticle. As the cuticle thickens it is more difficult for nematodes to penetrate and enter into plant roots. Therefore, arbuscular mycorrhizae help coffee plants to uptake and transport nutrients, improving its nutritional status and stabilizing nematode attacks. It is suggested that symbiotic interactions help neutralize parasitic interactions.
Evaluating Sensitivity to Different Options and Parameterizations of a Coupled Air Quality Modelling System over Bogotá, Colombia. Part I: WRF Model Configuration  [PDF]
Beatriz Reboredo, Raúl Arasa, Bernat Codina
Open Journal of Air Pollution (OJAP) , 2015, DOI: 10.4236/ojap.2015.42006
Abstract: Meteorological inputs are of great importance when implementing an air quality prediction system. In this contribution, the Weather Research and Forecast (WRF-ARW) model was used to compare the performance of the different cumulus, microphysics and Planet Boundary Layer parameterizations over Bogotá, Colombia. Surface observations were used for comparison and the evaluated meteorological variables include temperature, wind speed and direction and relative humidity. Differences between parameterizations were observed in meteorological variables and Betts-Miller-Janjic, Morrison 2-moment and BouLac schemes proved to be the best parameterizations for cumulus, microphysics and PBL, respectively. As a complement to this study, a WRF-Large Eddy Simulation was conducted in order to evaluate model results with finer horizontal resolution for air quality purposes.
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