1000 resultados para comparative urbanisation


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Control of Fasciola hepatica infections of livestock in the absence of vaccines depends largely on the chemical triclabendazole (TCBZ) because it is effective against immature and adult parasites. Overdependence on a single drug and improper application is considered a significant factor in increasing global reports of fluke resistant to TCBZ. The mode(s) of action and biological target(s) of TCBZ are not confirmed, delaying detection and the monitoring of early TCBZ resistance. In this study, to further understand liver fluke response to TCBZ, the soluble proteomes of TCBZ-resistant and TCBZ-susceptible isolates of F. hepatica were compared with and without in vitro exposure to the metabolically active form of the parent drug triclabendazole sulphoxide (TCBZ-SO), via two-dimensional gel electrophoresis (2-DE). Gel image analysis revealed proteins displaying altered synthesis patterns and responses both between isolates and under TCBZ-SO exposure. These proteins were identified by mass spectrometry supported by a F. hepatica expressed sequence tag (EST) data set. The TCBZ responding proteins were grouped into three categories; structural proteins, energy metabolism proteins, and “stress” response proteins. This single proteomic investigation supported the reductionist experiments from many laboratories that collectively suggest TCBZ has a range of effects on liver fluke metabolism. Proteomics highlighted differences in the innate proteome profile of different fluke isolates that may influence future therapy and diagnostics design. Two of the TCBZ responding proteins, a glutathione transferase and a fatty acid binding protein, were cloned, produced as recombinants, and both found to bind TCBZ-SO at physiologically relevant concentrations, which may indicate a role in TCBZ metabolism and resistance.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper explores a number of relocation outcomes for geographically mobile employees in the following three regions: Germany as the home country and destination for domestic assignments (n = 115), Western Europe (n = 116) and other countries (n = 236). The satisfaction with various aspects of the post-relocation environment, the perception of change between the pre- and post-relocation environment and the attachment to the post-relocation environment at various levels were compared between the three groups. For the European and international sub-samples differences in the ideal country and future plans were also investigated. The group that stood out most clearly was the domestic sub-sample. It emerged as the group least satisfied with their job or task characteristics, perceived significantly fewer changes in the environment and was comparatively eager to leave the site they were currently working at and the job they were currently employed in. The sometimes proposed redefinition of intra-European assignments as ‘quasi-domestic’ relocation appears to be inappropriate.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The energetic profile of an ion translated along the axis of an ion channel should reveal whether the structure corresponds to a functionally open or closed state of the channel. In this study, we explore the combined use of Poisson–Boltzmann electrostatic calculations and evaluation of van der Waals interactions between ion and pore to provide an initial appraisal of the gating state of a channel. This approach is exemplified by its application to the bacterial inward rectifier potassium channel KirBac3.1, where it reveals the closed gate to be formed by a ring of leucine (L124) side chains. We have extended this analysis to a comparative survey of gating profiles, including model hydrophobic nanopores, the nicotinic acetylcholine receptor, and a number of potassium channel structures and models. This enables us to identify three gating regimes, and to show the limitation of this computationally inexpensive method. For a (closed) gate radius of 0.4 nm

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In the present paper, we introduce a notion of a style representing abstract, complex objects having characteristics that can be represented as structured objects. Furthermore, we provide some mathematical properties of such styles. As a main result, we present a novel approach to perform a meaningful comparative analysis of such styles by defining and using graph-theoretic measures. We compare two styles by comparing the underlying feature sets representing sets of graph structurally. To determine the structural similarity between the underlying graphs, we use graph similarity measures that are computationally efficient. More precisely, in order to compare styles, we map each feature set to a so-called median graph and compare the resulting median graphs. As an application, we perform an experimental study to compare special styles representing sets of undirected graphs and present numerical results thereof. (C) 2007 Elsevier Inc. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Monthly samples of L. australis, V. spongiartum, P. bicolor and D. cuneata were collected over a period of 12 months from Princess Royal Harbour, Western Australia. Preliminary information on densities and biomass is given. Gonad histology points to seasonal reproductive cycles with autumn spawning in P. bicolor and D. cuneata and irregular spawning in V. spongiantm and L. australis. However, L. australis did show two peaks of larval brooding in the study period. Length-frequency data are discussed in the light of the proposed reproductive patterns for the four species. Allometric relationships between length and both height and width for all species are described and their value to each species assessed. Populations of L. australis from different habitats show significant differences in shell shape.