Search results for "Ciencias Biológicas"
showing 10 items of 794 documents
Nomenclatural changes in Apteranthes Mikan (Asclepiadoideae, Apocynaceae)
2006
El género Apteranthes Mikan se considera constituido por unos ocho táxones, en su mayoría distribuidos por el norte de África. Sin embargo, algunos de sus componentes han sido infravalorados en las revisiones más recientes del género, pese a estar bien caracterizados morfológica y biogeográficamente. En la presente contribución, se aportan datos que sirven para justificar la propuesta de dos nuevas combinaciones nomenclaturales: Apteranthes europaea subsp. negevensis (Zohari ex Feinbrun) M.B. Crespo –que incluye las poblaciones orientales de la especie–, y A. munbyana subsp. hispanica (Coincy) M.B. Crespo & Mateo –que se aplica las poblaciones del sudeste ibérico–. Para ambas se adjuntan ic…
Ophrys bombyliflora var. albarranii, var. nov. (Orchidaceae)
2015
Se describe una nueva variedad de Ophrys bombyliflora (Orchidaceae). Esta planta ha sido recolectada en Alcalá de Guadaíra (Sevilla, España). Se aportan determinados datos respecto a su morfología y ecología. A new variety of Ophrys bombyliflora (Orchidaceae) is described. This plant has been collected in Alcalá de Guadaíra (Seville, Spain). Morphological and ecological data are reported.
Una localidad nueva para Orchis champagneuxii y Orchis conica en el norte de Alicante
2006
Se da a conocer una nueva localidad en la que conviven dos orquídeas muy raras en el ámbito de la provincia de Alicante, y que resultan también escasas en la Comunidad Valenciana: Orchis champagneuxii Barnéoud [≡ O. morio subsp. champagneuxii (Barnéoud) E.G. Camus] y O. conica Willd. [− O. lactea auct.]. En ambos casos sólo se tiene referencias previas de su presencia en escasas localidades de las comarcas del norte de Alicante, a menudo en áreas próximas a la provincia de Valencia. Para ambas se aportan datos sobre su ecología y estado de conservación, y asimismo se propone la creación de una microrreserva de flora que asegure su continuidad en las comarcas alicantinas. A new site is repor…
The design of artificial nestboxes for the study of secondary hole-nesting birds: A review of methodological inconsistencies and potential biases
2010
The widespread use of artificial nestboxes has led to significant advances in our knowledge of the ecology, behaviour and physiology of cavity nesting birds, especially small passerines. Nestboxes have made it easier to perform routine monitoring and experimental manipulation of eggs or nestlings, and also repeatedly to capture, identify and manipulate the parents. However, when comparing results across study sites the use of nestboxes may also introduce a potentially significant confounding variable in the form of differences in nestbox design amongst studies, such as their physical dimensions, placement height, and the way in which they are constructed and maintained. However, the use of …
Scanning electron microscopy of Antarctophthirus microchir (Phthiraptera: Anoplura: Echinophthiriidae): Studying morphological adaptations to aquatic…
2012
The members of the Family Echinophthiriidae (Phthiraptera: Anoplura) are unique among insects because they infest hosts with an amphibious lifestyle. During their evolution they developed morphological traits that are reflected in unique features. The SEM is a helpful tool to analyze them. Knowing in detail the external structure of these lice is the first step to understand the whole process that derived from the co-adaptation of lice and pinnipeds to the marine environment. For the first time, we studied the external structure of all stages of an echinophthiriid louse. The results are discussed in the light of their evolutionary, functional, and ecological implications. Fil: Leonardi, Mar…
Anti-inflammatory properties of hydroalcoholic extracts of Argentine Puna plants
2015
The aim of this study is to evaluate the activity of thirteen hydroalcoholic extracts obtained from aerial parts of plants from Argentina Puna on pro-inflammatory enzymes and inflammatory mediators. Eleven extracts were non-cytotoxic on RAW 264.7. Data obtained suggest the capacity of these Argentine Puna plant extracts to inhibit the production of inflammatory mediators (nitric oxide and prostaglandin) at different levels. The plant extracts can affect enzymes expression and/or enzymes activity, and they can also act by NO scavenging. Each extract exerts its anti-inflammatory effect through different mechanisms. The inhibitory ability on pro-inflammatory enzymes by these hydroalcoholic ext…
Plantago amplexicaulis Cav. (Plantaginaceae) en la provincia de Castellón
2007
Se da a conocer la presencia de Plantago amplexicaulis Cav. en los alrededores del marjal de Almenara (Castellón). Ésta es su primera localidad castellonense y la más septentrional de su área de distribución. Así mismo, este hallazgo refuerza las citas clásicas de esta especie, que fue descrita del castillo de Sagunto (Valencia) y de donde no había vuelto a ser vista en tiempos recientes. La especie es lectotipificada y además se aportan datos sobre su comportamiento ecológico y fitosociológico en este territorio. Plantago amplexicaulis Cav. is reported from the surroundings of Almenara (Castellón Province). This is its first locality in Castellón province (E of Spain), the northernmost one…
Aportaciones a la flora palentina
2010
P. 56-61 Se comentan hallazgos de plantas vasculares poco conocidas en el territorio palentino y se aportan algunas novedades para la provincia de notable interés corológico. Se detalla el estatus de conservación de aquellos táxones incluidos en documentos técnicos y listados oficiales de protección de flora SI
Population structure and reticulate evolution of Saccharomyces eubayanus and its lager-brewing hybrids
2014
Reticulate evolution can be a major driver of diversification into new niches, especially in disturbed habitats and at the edges of ranges. Industrial fermentation strains of yeast provide a window into these processes, but progress has been hampered by a limited understanding of the natural diversity and distribution of Saccharomyces species and populations. For example, lager beer is brewed with Saccharomyces pastorianus, an alloploid hybrid of S. cerevisiae and S. eubayanus, a species only recently discovered in Patagonia, Argentina. Here, we report that genetically diverse strains of S. eubayanus are readily isolated from Patagonia, demonstrating that the species is well established the…
Ancient proteins resolve the evolutionary history of Darwin's South American ungulates.
2015
No large group of recently extinct placental mammals remains as evolutionarily cryptic as the approximately 280 genera grouped as 'South American native ungulates'. To Charles Darwin, who first collected their remains, they included perhaps the 'strangest animal[s] ever discovered'. Today, much like 180 years ago, it is no clearer whether they had one origin or several, arose before or after the Cretaceous/Palaeogene transition 66.2 million years ago, or are more likely to belong with the elephants and sirenians of superorder Afrotheria than with the euungulates (cattle, horses, and allies) of superorder Laurasiatheria. Morphology-based analyses have proved unconvincing because convergences…