587 research outputs found

    Sketched Answer Set Programming

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    Answer Set Programming (ASP) is a powerful modeling formalism for combinatorial problems. However, writing ASP models is not trivial. We propose a novel method, called Sketched Answer Set Programming (SkASP), aiming at supporting the user in resolving this issue. The user writes an ASP program while marking uncertain parts open with question marks. In addition, the user provides a number of positive and negative examples of the desired program behaviour. The sketched model is rewritten into another ASP program, which is solved by traditional methods. As a result, the user obtains a functional and reusable ASP program modelling her problem. We evaluate our approach on 21 well known puzzles and combinatorial problems inspired by Karp's 21 NP-complete problems and demonstrate a use-case for a database application based on ASP.Comment: 15 pages, 11 figures; to appear in ICTAI 201

    INTERNAL SEGMENTATION, RESIDENTIAL PATTERNS AND JOB-RELATED SPATIAL MOBILITY FOR INDEPENDENT PROFESSIONALS. AN ORIGINAL ANALYSIS ON PRIMARY DATA.

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    This study challenges the traditions of the sociology of work and industrial relations by taking into consideration a new emergent category of workers: the Independent Professionals (IPros). Recent data (Labour Statistics) provide some hints on the relevance of the phenomenon: self-employed workers in advanced services (finance, counselling, producing-distributing information, auditing and so on) have increased their share in employment in most countries. As a recent survey (Edelman Berland 2014) pointed out, 53 million Americans are doing freelance work (53 percent of the entire workforce) Despite these figures, the phenomenon is still overlooked by the academic literature. The aim is to provide a first description of this phenomenon not only from a mere labour perspective, but considering spatial practices and lifestyles too. Indeed labour studies and economic sociology should not avoid considering space and time as two main dimensions shaping their object of study: workers are not abstract entities, they are fully part of the material environment they move in. Labour markets, Welfare regimes, and spatial processes play together. Mobility-related literature traditionally identifies two different forms of moving to get a job: mobility of less skilled people for whom becoming mobile is the only way to get a job, and mobility of highly qualified people, looking for career opportunities. What is missing in this binary analysis is a new intermediate workforce, the self-employed independent professionals (Ipros) who often experience long distance interregional commuting patterns. Among them there are young high-skilled people with low income who are likely to undergo phenomena of spatial exclusion at the regional level. Where do they live? Where do they work? What are the explaining micro and macro variables? These questions will be discussed in the contribution which has firstly a descriptive and investigative aim. The method of study is based on quantitative analysis mainly performed on web survey data, due to the lack of available offical data sources in Italy. Specifically we provide a detailed description of survey design and data collection process, with a focus on methodological strategies applied for data cleaning, coding and editing in order to better highlight first descriptive results related to research questions. GIS (Geographical Information System) tools have been applied to survey data in order to provide a full extensive spatial description of social phenomena investigated: the core analysis is based on GIS and spatial statistics techniques by using data collected at micro and macro levels

    Hydrogen sulfide:a novel mechanism for the vascular protection by resveratrol under oxidative stress in mouse aorta

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    Reactive oxygen species (ROS) decreases bioavailability of nitric oxide (NO) and impairs NO-dependent relaxations. Like NO, hydrogen sulfide (H2S) is an antioxidant and vasodilator; however, the effect of ROS on H2S-induced relaxations is unknown. Here we investigated whether ROS altered the effect of H2S on vascular tone in mouse aorta and determined whether resveratrol (RVT) protects it via H2S. Pyrogallol induced ROS formation. It also decreased H2S formation and relaxation induced by l-cysteine and in mouse aorta. Pyrogallol did not alter sodium hydrogensulfide (NaHS)-induced relaxation suggesting that the pyrogallol effect on l-cysteine relaxations was due to endogenous H2S formation. RVT inhibited ROS formation, enhanced l-cysteine-induced relaxations and increased H2S level in aortas exposed to pyrogallol suggesting that RVT protects against "H2S-dysfunctions" by inducing H2S formation. Indeed, H2S synthesis inhibitor AOAA inhibited the protective effects of RVT. RVT had no effect on Ach-induced relaxation that is NO dependent and the stimulatory effect of RVT on H2S-dependent relaxation was also independent of NO. These results demonstrate that oxidative stress impairs endogenous H2S-induced relaxations and RVT offers protection by inducing H2S suggesting that targeting endogenous H2S pathway may prevent vascular dysfunctions associated by oxidative stress

    Utility of the SENIORS elderly heart failure risk model applied to the RICA registry of acute heart failure

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    Background: Heart failure (HF) is predominantly a disease of the elderly. Reliable risk stratification would help in the management of this population, but no model has been well evaluated in elderly HF patients in both acute and chronic settings and not being restricted by ejection fraction. To evaluate the utility of the SENIORS risk model, developed from a clinical trial of elderly patients with chronic HF, in an independent cohort (National Spanish Registry: RICA) of elderly acute HF patients. Methods: We applied the SENIORS risk model to 926 patients in RICA to estimate risk at one year of a) composite outcome of all-cause mortality or cardiovascular hospital admission and b) all-cause mortality. Results: In the RICA registry mean age was 78 years, mean ejection fraction 51% and 87% were in NYHA II and III. At one year death/CV hospitalization occurred in 31.9% and all-cause mortality in 19.5%. The risk model provided good separation of Kaplan Meier curves stratified by tertile for death/CV hospitalization and all-cause mortality. The observed versus expected rates of death/CV hospitalization in the lowest, middle and highest risk tertiles were (%) 34/24, 45/41 and 57/67, and for death 13/16, 32/38 and 44/70 respectively. C-statistic for all-cause mortality or CV hospitalization was 0.60 and for all-cause mortality 0.66. Conclusion: The SENIORS risk model was a reliable tool for relative risk stratification among acute heart failure patients in a “real world” registry, but predicted versus observed risk showed some variability. The model provides a useful basis for clinical risk prediction

    Undergraduate Commencement Exercises Program, June 20, 1970.

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    Bryant University Undergraduate Commencement Exercises Program, June 20, 1970

    Bioenergetic relevance of hydrogen sulfide and the interplay between gasotransmitters at human cystathionine ÎČ-synthase

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    Merely considered as a toxic gas in the past, hydrogen sulfide (H2S) is currently viewed as the third ‘gasotransmitter’ in addition to nitric oxide (NO) and carbon monoxide (CO), playing a key signalling role in human (patho)physiology. H2S can either act as a substrate or, similarly to CO and NO, an inhibitor of mitochondrial respiration, in the latter case by targeting cytochrome c oxidase (CcOX). The impact of H2S on mitochondrial energy metabolism crucially depends on the bioavailability of this gaseous molecule and its interplay with the other two gasotransmitters. The H2S-producing human enzyme cystathionine ÎČ-synthase (CBS), sustaining cellular bioenergetics in colorectal cancer cells, plays a role in the interplay between gasotransmitters. The enzyme was indeed recently shown to be negatively modulated by physiological concentrations of CO and NO, particularly in the presence of its allosteric activator S-adenosyl-L-methionine (AdoMet). These newly discovered regulatory mechanisms are herein reviewed. This article is part of a Special Issue entitled ‘EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2–6, 2016’, edited by Prof. Paolo Bernardi

    The novel mitochondria-targeted hydrogen sulfide (H2S) donors AP123 and AP39 protect against hyperglycemic injury in microvascular endothelial cells in vitro.

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    The development of diabetic vascular complications is initiated, at least in part, by mitochondrial reactive oxygen species (ROS) production in endothelial cells. Hyperglycemia induces superoxide production in the mitochondria and initiates changes in the mitochondrial membrane potential that leads to mitochondrial dysfunction. Hydrogen sulfide (H2S) supplementation has been shown to reduce the mitochondrial oxidant production and shows efficacy against diabetic vascular damage in vivo. However, the half-life of H2S is very short and it is not specific for the mitochondria. We have therefore evaluated two novel mitochondria-targeted anethole dithiolethione and hydroxythiobenzamide H2S donors (AP39 and AP123 respectively) at preventing hyperglycemia-induced oxidative stress and metabolic changes in microvascular endothelial cells in vitro. Hyperglycemia (HG) induced significant increase in the activity of the citric acid cycle and led to elevated mitochondrial membrane potential. Mitochondrial oxidant production was increased and the mitochondrial electron transport decreased in hyperglycemic cells. AP39 and AP123 (30-300nM) decreased HG-induced hyperpolarisation of the mitochondrial membrane and inhibited the mitochondrial oxidant production. Both H2S donors (30-300nM) increased the electron transport at respiratory complex III and improved the cellular metabolism. Targeting H2S to mitochondria retained the cytoprotective effect of H2S against glucose-induced damage in endothelial cells suggesting that the molecular target of H2S action is within the mitochondria. Mitochondrial targeting of H2S also induced >1000-fold increase in the potency of H2S against hyperglycemia-induced injury. The high potency and long-lasting effect elicited by these H2S donors strongly suggests that these compounds could be useful against diabetic vascular complications

    Managing data through the lens of an ontology

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    Ontology-based data management aims at managing data through the lens of an ontology, that is, a conceptual representation of the domain of interest in the underlying information system. This new paradigm provides several interesting features, many of which have already been proved effective in managing complex information systems. This article introduces the notion of ontology-based data management, illustrating the main ideas underlying the paradigm, and pointing out the importance of knowledge representation and automated reasoning for addressing the technical challenges it introduces

    A rapid spectroscopic method to detect the fraudulent treatment of tuna fish with carbon monoxide

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    Carbon monoxide (CO) can be used to treat fresh meat and fish in order to retain its 'fresh' red colour appearance for a longer period of time. In fact, upon aging, myoglobin is oxidized to met-myoglobin with the concomitant blue-shift and broadening of the Soret maximum, which brings about a change in the colour of the fish, revealing that it is no longer fresh. The use of carbon monoxide, which reacts with the oxy-myoglobin to form a fairly stable cherry red carboxy-myoglobin complex may mask spoilage, because the CO-complex can be stable beyond the microbiological shelf life of the meat. The presence of CO in tuna fish has been investigated by optical spectroscopy as the formation of the CO adduct can be easily detected by the combined analysis of electronic absorption spectra in their normal and second derivative modes, monitoring the intense Soret band at 420 nm. The presence of met- and oxy-myoglobin can obscure the presence of small amounts of the CO adduct; however, it can be revealed by chemically reducing the met- and oxy-forms to the deoxy-form in an anaerobic environment. This spectroscopic method provides a qualitatively rapid laboratory screening procedure for food control to unmask the presence of CO in frozen or fresh fish. (c) 2006 Elsevier Ltd. All rights reserved
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