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Search Results: 1 - 10 of 377257 matches for " PEDRO P. GARCILLáN "
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The Brahea edulis palm forest in Guadalupe Island: A North American fog oasis?
GARCILLáN,PEDRO P; VEGA,ERNESTO; MARTORELL,CARLOS;
Revista chilena de historia natural , 2012, DOI: 10.4067/S0716-078X2012000100011
Abstract: fog is a factor that affects deeply the structure of vegetation of coastal deserts. guadalupe is an oceanic island located 260 km off the coast of baja california, and is one of the few places of the sonoran desert coasts with scarped coastal topography and frequent fog. with the aim to identify the effect of fog on the community of the palm forest (palmar) of brahea edulis located in the northern tip of the island: (1) we analyzed the richness and composition of vascular plants in the palmar compared to the remainder of the island, and (2) we analyzed the altitudinal variation of the abundance of palms, herbs and mosses to identify if there is altitudinal variation of the vegetation. although species composition was not different between palmar and the rest of island, species richness and vascular plant cover were greater in the palmar. on the other hand, we found a clear altitudinal zonation of the vegetation in the palmar that is similar to that found in south american fog-driven plant communities such as the lomas. thus, the palmar community of guadalupe island may be considered as a fog oasis, one of the very few that occur in north america.
The Brahea edulis palm forest in Guadalupe Island: A North American fog oasis? El palmar de Brahea edulis de Isla Guadalupe: Un oasis de niebla en Norteamérica?
PEDRO P GARCILLáN,ERNESTO VEGA,CARLOS MARTORELL
Revista chilena de historia natural , 2012,
Abstract: Fog is a factor that affects deeply the structure of vegetation of coastal deserts. Guadalupe is an oceanic island located 260 km off the coast of Baja California, and is one of the few places of the Sonoran Desert coasts with scarped coastal topography and frequent fog. With the aim to identify the effect of fog on the community of the palm forest (palmar) of Brahea edulis located in the northern tip of the island: (1) we analyzed the richness and composition of vascular plants in the palmar compared to the remainder of the island, and (2) we analyzed the altitudinal variation of the abundance of palms, herbs and mosses to identify if there is altitudinal variation of the vegetation. Although species composition was not different between palmar and the rest of island, species richness and vascular plant cover were greater in the palmar. On the other hand, we found a clear altitudinal zonation of the vegetation in the palmar that is similar to that found in South American fog-driven plant communities such as the lomas. Thus, the palmar community of Guadalupe Island may be considered as a fog oasis, one of the very few that occur in North America. La niebla es un factor que afecta profundamente la estructura de la vegetación de los desiertos costeros. Guadalupe es una isla oceánica a 260 km de la costa de Baja California y constituye uno de los pocos lugares de la costa del Desierto Sonorense donde se reúnen una topografía escarpada próxima a la costa y una alta frecuencia de nieblas. Con el objeto de identificar el efecto de la niebla sobre la comunidad del palmar de Brahea edulis presente en la ladera norte de la isla: (1) analizamos la diferencia de la riqueza y la composición de plantas vasculares del palmar respecto del resto de la isla, y (2) analizamos la variación altitudinal de la abundancia de palmas, plantas acompa antes y musgo para determinar si existe variación altitudinal de la vegetación. Encontramos que, aunque la composición de plantas del palmar no fue diferente del resto de la isla, la riqueza de especies y la cobertura fueron claramente superiores en el palmar. Finalmente, constatamos una clara zonación altitudinal de la vegetación en el palmar semejante a la encontrada en las comunidades dependientes de la niebla en Sudamérica, tales como las lomas. Por tanto, la comunidad del palmar de Isla Guadalupe puede considerarse como un oasis de niebla, uno de los pocos existentes en Norteamérica.
Plastid DNA Diversity Is Higher in the Island Endemic Guadalupe Cypress than in the Continental Tecate Cypress
Patricia Rosas Escobar,David S. Gernandt,Daniel Pi?ero,Pedro P. Garcillán
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0016133
Abstract: Callitropsis guadalupensis (Guadalupe cypress) is endemic to Guadalupe Island, Mexico, where it is the dominant species of the only forest. The species has suffered declining numbers following the introduction of goats to the island over 150 years ago. Callitropsis guadalupensis is closely related to Callitropsis forbesii (Tecate cypress), distributed in small isolated populations in mainland Baja California and southern California. The objective of the present study was to compare the genetic diversity of the island endemic to the continental species.
Ecorregiones de la península de Baja California: Una síntesis
González-Abraham, Charlotte E.;Garcillán, Pedro P.;Ezcurra, Exequiel;,;
Boletín de la Sociedad Botánica de México , 2010,
Abstract: the biological singularity of the baja california peninsula has captured the attention of naturalists since long time ago. as result, a rich variety of ecological and biogeographical interpretations have been proposed. they share a common framework, but at the same time show disagreement. an exhaustive review of published literature was done to identify which ecoregions or transition zones show disagreement. we submitted the discordant transition zones to the analysis of regional experts during a workshop, and with the help of a geographical information system we generated decisions by consensus for the majority of discussed zones. reults are shown in a map of ecoregions of the baja california peninsula, as a synthesis of the long time effort of study and analysis developed by individuals and institutions on the natural scenario of the baja california peninsula.
ECORREGIONES DE LA PENíNSULA DE BAJA CALIFORNIA: UNA SíNTESIS
CHARLOTTE E. GONZáLEZ-ABRAHAM,PEDRO P. GARCILLáN,EXEQUIEL EZCURRA,EL GRUPO DE TRABAJO DE ECORREGIONES
Boletín de la Sociedad Botánica de México , 2010,
Abstract: La singularidad biológica de la península de Baja California ha capturado el interés de los naturalistas por largo tiempo. Fruto de ello ha sido la publicación de una rica variedad de interpretaciones geográficas de su escenario ecológico y biogeográfico. Aunque coincidentes en un marco común general, presentan también numerosas discrepancias. En este trabajo se revisa exhaustivamente la literatura publicada sobre el tema con el objeto de identificar las fronteras o zonas de transición que presentan mayor diversidad o discrepancia. Se sometió el diagnóstico al examen y discusión de un taller de expertos, el cual contó con el apoyo de un sistema de información geográfica, generando decisiones consensuadas. Los resultados se presentan en un mapa de regiones ecológicas de la península de Baja California como una síntesis del estudio e interpretación sobre las ecorregiones naturales de la península de Baja California.
The Repertoire of ICE in Prokaryotes Underscores the Unity, Diversity, and Ubiquity of Conjugation
Julien Guglielmini,Leonor Quintais,Maria Pilar Garcillán-Barcia,Fernando de la Cruz,Eduardo P. C. Rocha
PLOS Genetics , 2011, DOI: 10.1371/journal.pgen.1002222
Abstract: Horizontal gene transfer shapes the genomes of prokaryotes by allowing rapid acquisition of novel adaptive functions. Conjugation allows the broadest range and the highest gene transfer input per transfer event. While conjugative plasmids have been studied for decades, the number and diversity of integrative conjugative elements (ICE) in prokaryotes remained unknown. We defined a large set of protein profiles of the conjugation machinery to scan over 1,000 genomes of prokaryotes. We found 682 putative conjugative systems among all major phylogenetic clades and showed that ICEs are the most abundant conjugative elements in prokaryotes. Nearly half of the genomes contain a type IV secretion system (T4SS), with larger genomes encoding more conjugative systems. Surprisingly, almost half of the chromosomal T4SS lack co-localized relaxases and, consequently, might be devoted to protein transport instead of conjugation. This class of elements is preponderant among small genomes, is less commonly associated with integrases, and is rarer in plasmids. ICEs and conjugative plasmids in proteobacteria have different preferences for each type of T4SS, but all types exist in both chromosomes and plasmids. Mobilizable elements outnumber self-conjugative elements in both ICEs and plasmids, which suggests an extensive use of T4SS in trans. Our evolutionary analysis indicates that switch of plasmids to and from ICEs were frequent and that extant elements began to differentiate only relatively recently. According to the present results, ICEs are the most abundant conjugative elements in practically all prokaryotic clades and might be far more frequently domesticated into non-conjugative protein transport systems than previously thought. While conjugative plasmids and ICEs have different means of genomic stabilization, their mechanisms of mobility by conjugation show strikingly conserved patterns, arguing for a unitary view of conjugation in shaping the genomes of prokaryotes by horizontal gene transfer.
Human CD3γ, but not CD3δ, haploinsufficiency differentially impairs γδ versus αβ surface TCR expression
Mu?oz-Ruiz Miguel,Pérez-Flores Verónica,Garcillán Beatriz,Guardo Alberto C
BMC Immunology , 2013, DOI: 10.1186/1471-2172-14-3
Abstract: Background The T cell antigen receptors (TCR) of αβ and γδ T lymphocytes are believed to assemble in a similar fashion in humans. Firstly, αβ or γδ TCR chains incorporate a CD3δε dimer, then a CD3γε dimer and finally a ζζ homodimer, resulting in TCR complexes with the same CD3 dimer stoichiometry. Partial reduction in the expression of the highly homologous CD3γ and CD3δ proteins would thus be expected to have a similar impact in the assembly and surface expression of both TCR isotypes. To test this hypothesis, we compared the surface TCR expression of primary αβ and γδ T cells from healthy donors carrying a single null or leaky mutation in CD3G (γ+/ ) or CD3D (δ+/ , δ+/leaky) with that of normal controls. Results Although the partial reduction in the intracellular availability of CD3γ or CD3δ proteins was comparable as a consequence of the mutations, surface TCR expression measured with anti-CD3ε antibodies was significantly more decreased in γδ than in αβ T lymphocytes in CD3γ+/ individuals, whereas CD3δ+/ and CD3δ+/leaky donors showed a similar decrease of surface TCR in both T cell lineages. Therefore, surface γδ TCR expression was more dependent on available CD3γ than surface αβ TCR expression. Conclusions The results support the existence of differential structural constraints in the two human TCR isotypes regarding the incorporation of CD3γε and CD3δε dimers, as revealed by their discordant surface expression behaviour when confronted with reduced amounts of CD3γ, but not of the homologous CD3δ chain. A modified version of the prevailing TCR assembly model is proposed to accommodate these new data.
Blueprint for a minimal photoautotrophic cell: conserved and variable genes in Synechococcus elongatus PCC 7942
Luis Delaye, Carmen M González-Domenech, María P Garcillán-Barcia, Juli Peretó, Fernando de la Cruz, Andrés Moya
BMC Genomics , 2011, DOI: 10.1186/1471-2164-12-25
Abstract: By using a combination of methods we identified 170 xenologs, 136 ORFans and 1401 core genes in the genome of S. elongatus PCC 7942. These represent 6.5%, 5.2% and 53.6% of the annotated genes respectively. We considered that genes in genomic islands could be found if they showed a combination of: a) unusual G+C content; b) unusual phylogenetic similarity; and/or c) a small number of the highly iterated palindrome 1 (HIP1) motif plus an unusual codon usage. The origin of the largest genomic island by horizontal gene transfer (HGT) could be corroborated by lack of coverage among metagenomic sequences from a fresh water microbialite. Evidence is also presented that xenologous genes tend to cluster in operons. Interestingly, most genes coding for proteins with a diguanylate cyclase domain are predicted to be xenologs, suggesting a role for horizontal gene transfer in the evolution of Synechococcus sensory systems.Our estimates of genomic islands in PCC 7942 are larger than those predicted by other published methods like SIGI-HMM. Our results set a guide to non-essential genes in S. elongatus PCC 7942 indicating a path towards the engineering of a model photoautotrophic bacterial cell.The design and implementation of simpler biological systems is relevant for biotechnological applications, and as a way to address basic biological questions. In principle, simplified versions of extant cells should be easier to understand and engineer towards a variety of tasks like production of biomolecules or exploitation of metabolic or physiological process. Besides, the search for simpler cells through genome reduction might help to identify novel species-specific essential genes under a set of defined conditions. This in turn will lead to improvements in our understanding of the basic machinery of cells, and ultimately will shed light into the minimal and sufficient features required for life [1].Genomes of free living bacteria often contain a plethora of genes necessary to face a
La actividad física: una vía para mejorar los síntomas durante el climaterio
Quintero Paredes,Pedro P; Pérez Martín,Martha M;
Revista de Ciencias M??dicas de Pinar del R?-o , 2008,
Abstract: a descriptive and longitudinal study was carried out in all patients in the climateric stage who attended the gynecology office at "luis augusto turcios lima" out-patient clinic in pinar del río during january 1 to december 31 ,2005. the universe and sample were based on a total of 200 patients who were registered and followed. data were processed by percentage analysis. patients with spontaneous menopause attended the climacteric office more frequently than those women with surgical menopause. the short-term symptoms were the most present in these women . women in this stage do not receive a proper familiar support and the most used therapy is the combined one, with insufficient use of physical activity and sport. most women do not receive any help from a physical culture professional in spite of their interest in these activities in this stage of life.
La actividad física: una vía para mejorar los síntomas durante el climaterio Physical activity as a way to improve the symptoms during the climacteric
Pedro P Quintero Paredes,Martha M Pérez Martín
Revista de Ciencias M??dicas de Pinar del R?-o , 2008,
Abstract: Se realizó un estudio descriptivo y longitudinal de todas las pacientes en la etapa climatérica que asistieron a la consulta de Ginecología del Policlínico Universitario "Luis Augusto Turcios Lima" del municipio Pinar del Río, del 1ro de enero al 31 de diciembre del 2005. El universo y la muestra lo constituyeron el total de pacientes en etapa climatérica que asistieron a esta consulta, que fueron 200 pacientes que se les llenó la historia clínica y dio seguimiento en consulta. Los datos se procesaron mediante análisis porcentual. Las pacientes que asistieron con más frecuencia a la consulta de climaterio fueron las que tuvieron una menopausia espontánea seguida de las de causa artificial. Los síntomas que más aquejan a estas pacientes son los agrupados a corto plazo. Las mujeres en esta etapa no reciben un adecuado apoyo familiar y la terapia más usada es la combinada, con un uso insuficiente de la actividad física y el deporte. La mayoría de las mujeres no reciben ayuda de un profesional de la cultura física, y tienen gran interés en pertenecer a grupos especializados de mujeres en esta etapa. A descriptive and longitudinal study was carried out in all patients in the climateric stage who attended the Gynecology office at "Luis Augusto Turcios Lima" Out-patient Clinic in Pinar del Río during January 1 to December 31 ,2005. The universe and sample were based on a total of 200 patients who were registered and followed. Data were processed by percentage analysis. Patients with spontaneous menopause attended the climacteric office more frequently than those women with surgical menopause. The short-term symptoms were the most present in these women . Women in this stage do not receive a proper familiar support and the most used therapy is the combined one, with insufficient use of physical activity and sport. Most women do not receive any help from a physical culture professional in spite of their interest in these activities in this stage of life.
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