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    Branching: the Essence of Constraint Solving

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    This paper focuses on the branching process for solving any constraint satisfaction problem (CSP). A parametrised schema is proposed that (with suitable instantiations of the parameters) can solve CSP's on both finite and infinite domains. The paper presents a formal specification of the schema and a statement of a number of interesting properties that, subject to certain conditions, are satisfied by any instances of the schema. It is also shown that the operational procedures of many constraint systems including cooperative systems) satisfy these conditions. Moreover, the schema is also used to solve the same CSP in different ways by means of different instantiations of its parameters.Comment: 18 pages, 2 figures, Proceedings ERCIM Workshop on Constraints (Prague, June 2001

    Impaired Upregulation of the Costimulatory Molecules, CD27 and CD28, on CD4(+) T Cells from HIV Patients Receiving ART Is Associated with Poor Proliferative Responses.

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    HIV patients beginning antiretroviral therapy (ART) with advanced immunodeficiency often retain low CD4(+) T cell counts despite virological control. We examined proliferative responses and upregulation of costimulatory molecules, following anti-CD3 stimulation, in HIV patients with persistent CD4(+) T cell deficiency on ART. Aviremic HIV patients with nadir CD4(+) T cell counts <100 cells/µL and who had received ART for a median time of 7 (range 1-11) years were categorized into those achieving low (<350 cells/µL; n?=?13) or normal (>500 cells/µL; n?=?20) CD4(+) T cell counts. Ten healthy controls were also recruited. CD4(+) T cell proliferation (Ki67) and upregulation of costimulatory molecules (CD27 and CD28) after anti-CD3 stimulation were assessed by flow cytometry. Results were related to proportions of CD4(+) T cells expressing markers of T cell senescence (CD57), activation (HLA-DR), and apoptotic potential (Fas). Expression of CD27 and/or CD28 on uncultured CD4(+) T cells was similar in patients with normal CD4(+) T cell counts and healthy controls, but lower in patients with low CD4(+) T cell counts. Proportions of CD4(+) T cells expressing CD27 and/or CD28 correlated inversely with CD4(+) T cell expression of CD57, HLA-DR, and Fas. After anti-CD3 stimulation, induction of CD27(hi)CD28(hi) expression was independent of CD4(+) T cell counts, but lower in HIV patients than in healthy controls. Induction of CD27(hi)CD28(hi) expression correlated with induction of Ki67 expression in total, naïve, and CD31(+) naïve CD4(+) T cells from patients. In HIV patients responding to ART, impaired induction of CD27 and CD28 on CD4(+) T cells after stimulation with anti-CD3 is associated with poor proliferative responses as well as greater CD4(+) T cell activation and immunosenescence

    Environmental enrichment results in both brain connectivity efficiency and selective improvement in different behavioral tasks

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    Exposure to environmental enrichment (EE) has been a useful model for studying the effects of experience on brain plasticity, but to date, few is known about the impact of this condition on the brain functional networks that probably underlies the multiple behavioral improvements. Hence, we assessed the effect of an EE protocol in adult Wistar rats on the performance in several behavioral tasks testing different domains (Open field (OP): locomotor activity; Elevated-zero maze (EZM): anxiety-related behaviors; 5-choice serial reaction time task (5-CSRTT): attentional processes; 4-arm radial water maze (4-RAWM): spatial memory) in order to check its effectiveness in a wide range of functions. After this, we analyzed the functional brain connectivity underlying each experimental condition through cytochrome C oxidase (COx) histochemistry. Our EE protocol reduced both locomotor activity in the OP and anxiety-related behaviors in the EZM. On the other hand, enriched rats showed more accuracy in the 4-RAWM, whereas 5-CSRTT performance was not significantly ameliorated by EE condition. In relation to COx functional connectivity, we found that EE reduced the number of strong positive correlations both in basal and training conditions, suggesting a modulating effect on specific brain connections. Our results suggest that EE seems to have a selective effect on specific brain regions, such as prefrontal cortex and hippocampus, leading to a more efficient brain connectivity.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. PPIT.UMA.B1.2017/3

    Reducing the risk of heart disease among Indian Australians: knowledge, attitudes, and beliefs regarding food practices - a focus group study

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    BACKGROUND: Australia has a growing number of Asian Indian immigrants. Unfortunately, this population has an increased risk for coronary heart disease (CHD). Dietary adherence is an important strategy in reducing risk for CHD. This study aimed to gain greater understanding of the knowledge, attitudes and beliefs relating to food practices in Asian Indian Australians. METHODS: Two focus groups with six participants in each were recruited using a convenience sampling technique. Verbatim transcriptions were made and thematic content analysis undertaken. RESULTS: Four main themes that emerged from the data included: migration as a pervasive factor for diet and health; importance of food in maintaining the social fabric; knowledge and understanding of health and diet; and elements of effective interventions. DISCUSSION: Diet is a complex constructed factor in how people express themselves individually, in families and communities. There are many interconnected factors influencing diet choice that goes beyond culture and religion to include migration and acculturation. CONCLUSIONS: Food and associated behaviors are an important aspect of the social fabric. Entrenched and inherent knowledge, attitudes, beliefs and traditions frame individuals\u27 point of reference around food and recommendations for an optimal diet

    Uprolides N, O and P from the Panamanian Octocoral Eunicea succinea.

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    Three new diterpenes, uprolide N (1), uprolide O (2), uprolide P (3) and a known one, dolabellane (4), were isolated from the CH₂Cl₂-MeOH extract of the gorgonian octocoral Eunicea succinea, collected from Bocas del Toro, on the Caribbean coast of Panama. Their structures were determined using spectroscopic analyses, including 1D and 2D NMR and high-resolution mass spectrometry (HRMS) together with molecular modeling studies. Compounds 1-3 displayed anti-inflammatory properties by inhibiting production of Tumor Necrosis Factor (TNF) and Interleukin (IL)-6 induced by lipopolysaccharide (LPS) in murine macrophages

    Хромосомы и видообразование у туко-туко (Ctenomys, Hystricognathi, Rodentia)

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    Tuco-tucos, South American rodents of the genus Ctenomys represent an interesting model of speciation. Their strict territorial and solitary life under the earth, vast but highly fragmented habitats, low migration activity were the causes of their very fast radiation. About 60 species of this genus have been described. They are found in a variety of habitats, from the mountains of the Andes to the coastal dunes of the Atlantic, from humid steppes of Pampas to dry deserts of Chaco. Tuco-tucos have a very high level of chromosomal polymorphism and polytypism based on Robertsonian and whole-arm reciprocal translocations and inversions, and can therefore be used to test different versions of chromosomal speciation hypothesis. The classic version of this hypothesis emphasizes the sterility of the hybrids, due to incorrect or incomplete chromosome synapsis in heterozygotes for rearrangements, germ cells death, chromosome nondisjunction and the generation of unbalanced gametes. The modern version of chromosomal speciation hypothesis suggests that the reduction of gene flow across chromosomal hybrid zones is due to the suppression of recombination in hybrids around the break points of rearrangements distinguishing the parental species. Field studies have not revealed strong negative effects of chromosomal heterozygosity on the fitness of the carriers. These results cast doubt on the validity of the classic version of the hypothesis. Analysis of chromosome behavior in the meiotic prophase in the chromosomal heterozygotes revealed significant changes in the frequency and distribution of recombination: crossingover suppression around the breakpoint and chiasma distalization. These changes can modulate the flow of genes between chromosomal races and amplify the divergence which has arisen due to spatial isolation. These data confirm the recombinational model of chromosomal speciation.Fil: Torgasheva, Anna A.. Novosibirsk State University; Rusia. Institute of Cytology and Genetics; RusiaFil: Savchenko, Ekaterina. Institute of Cytology and Genetics; RusiaFil: Gomez Fernandez, Maria Jimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Mirol, Patricia Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Borodin, Pavel M.. Novosibirsk State University; Rusia. Institute of Cytology and Genetics; Rusi

    Molecular typing of the yeast species Dekkera bruxellensis and Pichia guilliermondii recovered from wine related sources

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    A total of 63 strains of Dekkera bruxellensis and 32 strains of Pichia guilliermondii isolated from wine related environments were identified by restriction analysis of the 5.8S-ITS region of the rDNA. These strains were subjected to intraspecific discrimination using mtDNA restriction and RAPD-PCR analysis. The isolates identified as D. bruxellensis yielded 3 different molecular patterns of mtDNA restriction using the endonuclease HinfI. The pattern A was the most frequent (58 strains) among strains from different sources, regions and countries. Pattern B (4 strains) and C (one strain) were determined in isolates from Portuguese wines. The discrimination among the pattern A strains was achieved by a RAPD-PCR assay with 3 primers (OPA-2, OPA-3 and OPA-9). A total of 12 haplotypes were obtained with the combination of the patterns provided by the 3 OPAs. The pattern 2 was the most frequent and extensively distributed being found in strains from different countries and from different sources like wine, barrique wood and insects. The strains of P. guilliermondii were characterized with restriction of mtDNA using the endonuclease HinfI yielding 7 different restriction patterns. These patterns were associated with different efficiencies of 4-ethylphenol production. Patterns A to D corresponded to 19 strains producing low levels of 4-ethylphenol (50 mg/l), when grown in synthetic media supplemented with 100 mg/l of p-coumaric acid. The high degree of polymorphism observed shows that intraspecific typing is essential for accurate yeast dissemination studies in wine related environments.www.elsevier.com/locate/ijfoodmicro DOI: 10.1016/j.ijfoodmicro.2005.05.01

    Influence of environmental heterogeneity on the distribution and persistence of a subterranean rodent in a highly unstable landscape

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    O.E.G was supported by the Marine Alliance for Science and Technology for Scotland.In this study we combine information from landscape characteristics, demographic inference and species distribution modelling to identify environmental factors that shape the genetic distribution of the fossorial rodent Ctenomys. We sequenced the mtDNA control region and amplified 12 microsatellites from 27 populations distributed across the Iberá wetland ecosystem. Hierarchical Bayesian modelling was used to construct phylogenies and estimate divergence times. We developed species distribution models to determine what climatic variables and soil parameters predicted species presence by comparing the current to the historic and predicted future distribution of the species. Finally, we explore the impact of environmental variables on the genetic structure of Ctenomys based on current and past species distributions. The variables that consistently correlated with the predicted distribution of the species and explained the observed genetic differentiation among populations included the distribution of well-drained sandy soils and temperature seasonality. A core region of stable suitable habitat was identified from the Last Interglacial, which is projected to remain stable into the future. This region is also the most genetically diverse and is currently under strong anthropogenic pressure. Results reveal complex demographic dynamics, which have been in constant change in both time and space, and are likely linked to the evolution of the Paraná River. We suggest that any alteration of soil properties (climatic or anthropic) may significantly impact the availability of suitable habitat and consequently the ability of individuals to disperse. The protection of this core stable habitat is of prime importance given the increasing levels of human disturbance across this wetland system and the threat of climate change.PostprintPeer reviewe
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