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Amphibian populations are declining due to a myriad of abiotic and biotic factors, including invasive species and pathogens. In temperate freshwater ecosystems, for example, amphibian populations are threatened by the predation of introduced salmonids. Salmonids not only directly predate upon amphibian eggs and larvae but may also transport deadly pathogens into freshwater systems. Though most research has focused on temperate systems, much less is known about the effects of introduced species in Neotropical streams. We conducted two experiments to investigate the impacts of rainbow trout (Oncorhynchus mykiss) in two Neotropical anurans.First, we assessed the effect of the rainbow trout on tadpole survivorship and morphology inNymphargus grandisonae, a glassfrog species endemic of the Andes. Tadpoles ofN. grandisonaewere subjected to three treatments involving the absence of rainbow trout (control) and its presence with different types of chemical cues – kairomones (from rainbow trout) and cue alarms (from tadpole prey); the results show that the presence of rainbow trout affects the larval morphology of this glassfrog. In the second experiment, to test whether rainbow trout is a vector of the pathogenic freshwater moldSaprolegnia diclina(Oomycetes), eggs ofEngystomops petersiwere placed with infected and uninfected rainbow trout. There was a high mortality rate in the embryos ofE. petersiexposed to trout infected withS. diclina. This represents the first evidence that rainbow trout may have a direct negative effect on Neotropical amphibian populations, and thus should be considered a threat. Management programs should be implemented to eradicate trout from Andean rivers, especially in areas with high number of endangered amphibians. [ABSTRACT FROM PUBLISHER]

The objective of this paper is to compare the lipid content and composition of biomass produced by a consortium of microalgae and bacteria, cultivated under different solar radiation intensities and tropical conditions in pilot-scale high-rate ponds (HRPs) using domestic sewage as culture medium. The treatment system consisted of an upflow anaerobic sludge blanket reactor followed by UV disinfection and six HRPs covered with shading screens that blocked 9%, 18%, 30%, 60% and 80% of the solar radiation. The total lipid content does not vary significantly among the units, showing a medium value of 9.5%. The results show that blocking over 30% of the solar radiation has a negative effect on the lipid productivity. The units with no shading and with 30% and 60% of solar radiation blocking have statistically significant lipid productivities, varying from 0.92 to 0.96 g m−2 day−1. Besides radiation, other variables such as volatile suspended solids and chlorophyll-aare able to explain the lipid accumulation. The lipid profile has a predominance of C16, C18:1 and C18:3 acids. The unsaturation of fatty acids increases with the reduction in solar radiation. On the other hand, the effect of polyunsaturation is not observed, which is probably due to the presence of a complex and diverse biomass. [ABSTRACT FROM PUBLISHER]

Hepatocellular carcinoma (HCC) management takes into account clinical and radiological indings, such as tumor stage, hepatic functional status and clinical symptoms. It is necessary to evaluate the number, size and location of the lesions. However, lesion aggressiveness is not considered in this therapeutic worklow, although the biology and the growth rate of the lesions have an important impact on survival. The aim of this work was to establish if the quantitative pharmacokinetic assessment of dynamic contrast-enhanced magnetic resonance images of HCC can separate lesions with different microvascular properties and biological evolution. Forty ive patients with HCC and dynamic contrast-enhanced MRI examinations were included and several pharmacokinetic parameters were calculated. Statistical clusterization techniques were applied and two clearly distinct groups were obtained by using vascular properties and average lesion size. These groups differed by the proportion of deceased patients, although no statistically signiicant differences were found between the average survival times of both groups. [ABSTRACT FROM AUTHOR]

In the preceding paper, a method for mobile robot navigation control based on discrimination of multiple artificial fields was introduced. In this second paper, the method is extended to robot formations. Experimental demonstrations are presented taking examples of four types of formations. The experiments cover formation initialization, maneuvering, obstacle avoidance and formation switching. [ABSTRACT FROM AUTHOR]

The paper introduces a method for local navigation of mobile robots based on the discrimination of multiple artificial fields, which correspond to targets, obstacles, robots and, if this is the case, robot collectives. Instead of just adding up all potentials, the robot discerns the pertinent potentials at its location and applies a set of motion decisions at each moment. Satisfactory results are obtained. This is the first paper of a more extensive work dealing with individual robots, unorganized groups of robot and robot formations. Here, the method is introduced, with examples for a single robot and for several independent robots. [ABSTRACT FROM AUTHOR]

This paper describes how to use the information coming from applying the EFQM excellence model to analyse the perception that the members of an organisation have of it regarding their business vision. Such an analysis is made on the basis of the EFQM excellence model criteria and by applying statistical data analysis techniques. With this study, besides detecting both the strong and weak areas of actuation on which an organisation should focus and act, it is also possible to detect the relationships between the personal characteristics of members of the organisation and their business vision. The main goal is that organisations are able to reach excellence by jointly using an assessment method (the EFQM excellence model) and posterior statistical data analysis techniques (uni-variant and multi-variant). These techniques enable one to complement and enlarge the potential of the EFQM excellence model. Finally, the procedure is illustrated by presenting the main results of applying it to a real case of the Permanent Training Centre of the Polytechnic University of Valencia in Spain. [ABSTRACT FROM AUTHOR]

p300 is a multifunctional transcriptional coactivator that serves as an adapter for several transcription factors including nuclear steroid hormone receptors, p300 possesses an intrinsic histone acetyltransferase (HAT) activity that may be critical for promoting steroid-dependent transcriptional activation. In osteoblastic cells, transcription of the bone-specific osteocalcin (OC) gene is principally regulated by the Runx2/Cbfa1 transcription factor and is stimulated in response to vitamin D[sub 3] via the vitamin D[sub 3] receptor complex. Therefore, we addressed p300 control of basal and vitamin D[sub 3]-enhanced activity of the OC promoter. We find that transient overexpression of p300 results in a significant dose-dependent increase of both basal and vitamin D[sub 3]-stimulated OC gene activity. This stimulatory effect requires intact Runx2/Cbfa1 binding sites and the vitamin D-responsive element. In addition, by coimmunoprecipitation, we show that the endogenous Runx2/ Cbfa1 and p300 proteins are components of the same complexes within osteoblastic cells under physiological concentrations. We also demonstrate by chromatin immunoprecipitation assays that p300, Runx2/Cbfa1, and 1α,25-dihydroxyvitamin D[sub 3] receptor interact with the OC promoter in intact osteoblastic cells expressing this gene. The effect of p300 on the OC promoter is independent of its intrinsic HAT activity, as a HAT-deficient p300 mutant protein up-regulates expression and cooperates with P/CAF to the same extent as the wild-type p300. On the basis of these results, we propose that p300 interacts with key transcriptional regulators of the OC gene and bridges distal and proximal OC promoter sequences to facilitate responsiveness to vitamin D[sub 3]. [ABSTRACT FROM AUTHOR]