Search results for "Arid"

Entropía democrática

2007

La amistad y el amor en el epistolario de Séneca

2008

Joaquin.Beltran@uv.es El motivo por el que nos hemos decidido a estudiar en un mismo trabajo la amistad y el amor no es otro que histórico, por la conocida ambigüedad en la que se movían los primitivos filósofos griegos y, además, para llegar a saber la posición concreta de Séneca. Ello nos ha llevado a intentar codificar su pensamiento sobre la amistad y el amor en relación, sobre todo, con Aristóteles y Cicerón. Así, hemos intentado demostrar que Séneca ha unido a los conceptos de amistad e incluso amor otras ideas nuevas, que le dan un aire diferente, como la de solidaridad, asociación o sociedad, y que nos inducen a pensar en una definición afirmativa y muy positiva de la amistad frente…

A survey of the function of the lethal kettle traps of Arisaema (Araceae), with records of pollinating fungus gnats from Nepal

2000

Abstract Evidence from recent research combined with an evaluation of the literature indicates that Arisaema is adapted to pollination by fungus gnats. It apparently shares this peculiarity among aroids only with the distantly related genus Arisarum . In addition to previous records from Japan and North America, systematic collections from nine Arisaema species during several expeditions in the Himalayas in Nepal showed that, although other less efficient insect groups may participate, the nematoceran families Mycetophilidae and Sciaridae are the principal pollen vectors; they best fit the pollination apparatus of the mainly (para)dioecious kettle trap blossoms. A total of 16 fungus gnat ge…

Effet de l'environnement sur l'interaction entre les gammares (Crustacea : Amphipoda) et leurs parasites manipulateurs acanthocéphales

2016

Many parasites with complex life cycle have developed the ability to alter the phenotype of their hosts. It is recognized that such changes in appearance and behavior are responsible for an increase in the probability of predation of their intermediate hosts by their definitive hosts. This phenomenon of parasite manipulation can have numerous consequences at the scale of the ecosystem, modifying the interactions between host populations and altering their ecological role. However, manipulative parasites received little attention from an ecological point of view. Thus, the effect of the environment on the interaction between these parasites and their hosts, in particular in terms of manipula…

Development of injectable and durable kefiran hydro-alcoholic gels.

2020

Injectable, in-situ forming kefiran gels have been developed for potential applications as implantable drug delivery devices or scaffolds for tissue regeneration. Concentrated solutions (4, 5 and 6%w) of kefiran, extracted from kefir grains, have been assessed in term of viscosity and injectability through G26 syringe needles, and for their ability to undergo gelation upon mixing with different alcohols. Propylene glycol (PG) has been selected as gelling agent because it ensures homogenous gelation in relatively short times (from few minutes up to 6 h). The investigation of the rheological behavior of kefiran/PG gels varying polymer concentration and temperature (25 degrees C and 37 degrees…

Hybridization between mouse lemurs in an ecological transition zone in southern Madagascar

2009

Hybrid zones in ecotones can be useful model systems for the study of evolutionary processes that shape the distribution and discreteness of species. Such studies could be important for an improved understanding of the complex biogeography of Madagascar, which is renowned for its outstanding degree of small-scale endemism. Certain forest remnants in central Madagascar indicate that transitional corridors across the island could have connected microendemics in different forest types in the past. Evolutionary processes in such corridors are difficult to study because most of these corridors have disappeared due to deforestation in central Madagascar. We studied a hybrid zone in one of the few…

Regulation of the expression of inducible nitric oxide synthase.

2003

Nitric oxide (NO), generated by the inducible isoform of nitric oxide synthase (iNOS), has been described to have beneficial microbicidal, antiviral, antiparasital, immunomodulatory, and antitumoral effects. However, aberrant iNOS induction at the wrong place or at the wrong time has detrimental consequences and seems to be involved in the pathophysiology of several human diseases. iNOS is primarily regulated at the expression level by transcriptional and post-transcriptional mechanisms. iNOS expression can be induced in many cell types with suitable agents such as bacterial lipopolysaccharides (LPS), cytokines, and other compounds. Pathways resulting in the induction of iNOS expression may…

Vitamin A modulates the effects of thyroid hormone on UDP-glucuronosyltransferase expression and activity in rat liver.

2002

We studied the influence of thyroid hormones and vitamin A status on the regulation of UDP-glucuronosyltransferase (UGT) expression and the glucuronidation of thyroid hormones by UGTs. For this, we used an original model of rats fed with different vitamin A diets and implanted subcutaneously by osmotic minipumps delivering vehicle or thyroid hormones, which permitted the control of plasma thyroid hormone concentrations. The activity and expression of family 1 UGTs are correlated and were significantly modified by both thyroid status and amounts of retinol in the diet. Dietary vitamin A did not perturbe the UGT1A expression in thyroidectomized animals. Thyroid hormones and dietary vitamin A …

¿Cómo deciden les jóvenes la transición a la educación postobligatoria? Diferencias entre centros públicos y privados-concertados

2017

Background of INCASI Project H2020-MSCA-RISE-2015 GA 691004. WP1: Compilation El objetivo del presente artículo es examinar el papel que juega la titularidad del centro en el que se cursa la educación secundaria obligatoria (ESO) en la decisión de transitar a la educación postobligatoria. En dicha encrucijada se contemplan también otras variables que se han constatado de gran peso en la toma de decisión como son las notas previas obtenidas, el nivel formativo familiar, el sexo, las expectativas y las aspiraciones, partiendo del modelo decisional de transiciones educativas[1] que contempla el modelo de Boudon sobre los efectos primarios y secundarios. Los resultados obtenidos son los derivad…

Identification of two additives, locust bean gum (E-410) and guar gum (E-412), in food products by DNA-based methods.

2004

Locust bean gum (E-410) and guar gum (E-412) are high molecular weight galactomannans used by the food industry as versatile food additives. The compounds, although chemically closely related, do not have the same functional properties when used in foods, and the substitution or unadvertised addition of either could change the desired qualities of the product. Analytical discrimination between E-410 and E-412 is technically difficult since they only differ in their galactose: mannose ratios, being 1 : 4 and 1 : 2 for locust bean gum and guar gum, respectively. A qualitative DNA-based method is reported for the authentication of additives E-410 and E-412 in finished food products (ice cream,…