High-performance diode-pumped Nd:YLF amplifier

We report on the performance of a multipass diode-pumped amplifier design to provide a combination of high gain and efficiency with high stability. A simple rod-cavity design and the establishment of quasi-steady-state operation resulted in a saturated gain of over 6000 at an average output intensity during the pulse train of 7 kW/cm2. The amplifier showed an output stability of 0.2% rms in the short-term and 0.7% rms in the long-term and an output intensity insensitive to input power changes. Zernike analysis of the measurements of pump distortion showed an almost pure astigmatic phase error that can be compensated up to high average power levels.     

Involvement of growth factors in thymic involution

The thymus undergoes an age-dependent degenerative process which is mainly characterized by a progressive loss of lymphoid tissue. Thymic involution is particularly important in relation to immunosenescence and its various associated diseases; this fact has prompted many studies aimed at understanding the causes and mechanisms of thymic degeneration which may, ultimately, lead to the possibility of manipulating it. In this sense, one of the aspects which has deserved most attention is the thymic microenvironment, and more precisely, the many growth factors to which the cells present in the organ are exposed. Thus, the levels of several of such factors have been reported to undergo age-dependent changes in the thymus, which may point at an influence on the regression of the organ. In this article we consider which growth factors and growth factor receptors occur in the vertebrate thymus. Then, focusing on those whose influences are better documented, i.e., neurotrophins, cytokines and IGFs, we discuss their potential role in the organ and the possibility of their being involved in thymic involution.     

Grid Data Management: Open Problems and New Issues

Initially developed for the scientific community, Grid computing is now gaining much interest in important areas such as enterprise information systems. This makes data management critical since the techniques must scale up while addressing the autonomy, dynamicity and heterogeneity of the data sources. In this paper, we discuss the main open problems and new issues related to Grid data management. We first recall the main principles behind data management in distributed systems and the basic techniques. Then we make precise the requirements for Grid data management. Finally, we introduce the main techniques needed to address these requirements. This implies revisiting distributed database techniques in major ways, in particular, using P2P techniques. Work partially funded by ARA “Massive Data” of the French ministry of research (project Respire), the European Strep Grid4All project, the CAPES–COFECUB Daad project and the CNPq–INRIA Gridata project.     

Compositional State Space Reduction Using Untangled Actions

We propose a compositional technique for efficient verification of networks of parallel processes. It is based on an automatic analysis of LTSs of individual processes (using a failure-based equivalence which preserves divergences) that determines their sets of “conflict-free” actions, called untangled actions. Untangled actions are compositional, i.e. synchronisation on untangled actions will not destroy their “conflict-freedom”. For networks of processes, using global untangled actions derived from local ones, efficient reduction algorithms have been devised for systems with a large number of small processes running in parallel.     

PHRASE AND NGRAM-BASED STATISTICAL MACHINE TRANSLATION SYSTEM COMBINATION

Multiples translations can be computed by one machine translation (MT) system or by different MT systems. We may assume that different MT systems make different errors due to using different models, generation strategies, or tweaks. An investigated technique, inherited from automatic speech recognition (ASR), is the so-called system combination that is based on combining the outputs of multiples MT systems. We combine the outputs of a phrase- and Ngram-based Statistical MT (SMT) systems using statistical criteria and additional rescoring features.     

Collaborative cross-checking to enhance resilience

Resilience, the ability to adapt or absorb disturbance, disruption, and change, may be increased by team processes in a complex, socio-technical system. In particular, collaborative cross-checking is a strategy where at least two individuals or groups with different perspectives examine the others’ assumptions and/or actions to assess validity or accuracy. With this strategy, erroneous assessments or actions can be detected quickly enough to mitigate or eliminate negative consequences. In this paper, we seek to add to the understanding of the elements that are needed in effective cross-checking and the limitations of the strategy. We define collaborative cross-checking, describe in detail three healthcare incidents where collaborative cross-checks played a key role, and discuss the implications of emerging patterns.     

Comparison of a static and a dynamic in vitro model to estimate the bioaccessibility of As, Cd, Pb and Hg from food reference materials Fucus sp. (IAEA-140/TM) and Lobster hepatopancreas (TORT-2)

Bioaccessibility, the fraction of an element solubilized during gastrointestinal digestion and available for absorption, is a factor that should be considered when evaluating the health risk of contaminants from food. Static and dynamic models that mimic human physiological conditions have been used to evaluate bioaccessibility. This preliminary study compares the bioaccessibility of arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) in two food certified reference materials (CRMs) (seaweed: Fucus sp., IAEA-140/TM; Lobster hepatopancreas: TORT-2), using two in vitro gastrointestinal digestion methods: a static method (SM) and a dynamic multicompartment method (TIM-1). There are significant differences (p < 0.05) between the bioaccessible values of As, Cd, Pb and Hg obtained by SM and TIM-1 in the two CRMs. The specific form in which the elements studied are present in the CRM may help to explain the bioaccessibility values obtained.     

Transepithelial transport across Caco-2 cell monolayers of antihypertensive egg-derived peptides. PepT1-mediated flux of Tyr-Pro-Ile

This paper examines the in vitro transepithelial transport of antihypertensive peptides derived from egg proteins using Caco-2 cell monolayers. Ovokinin (FRADHPFL) was absorbed intact through the Caco-2 cell epithelium, although it was also susceptible to the action of brush-border aminopeptidases that yielded shorter fragments prior to their transport. The tripeptide YPI was resistant to cellular peptidases and transported through the monolayer, what suggests that the reduction in systemic blood pressure caused by this peptide may be mediated by effects at tissue level. Its pathway for transepithelial absorption was examined using inhibitors of the different mechanisms for oligopeptide transport in the intestinal tract. The main route involved in the transepithelial flux of YPI is probably the peptide H(+)-coupled transporter PepT1. These results highlight the potential of antihypertensive peptides to be used in the formulation of functional foods.     

Synthesis of unsaturated polyesters of increased solubility in styrene

The present study presents the synthesis of unsaturated polyester resins using only one glycol i.e., ethylene glycol. Polyesters of inorganic solubility in styrene were prepared. Properties of the resins in the noncrosslinked state in the process of crosslinking and after curing were studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3143–3150, 2006