876 resultados para Quantified Reflective Logic


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We modelled the distributions of two toads (Bufo bufo and Epidalea calamita) in the Iberian Peninsula using the favourability function, which makes predictions directly comparable for different species and allows fuzzy logic operations to relate different models. The fuzzy intersection between individual models, representing favourability for the presence of both species simultaneously, was compared with another favourability model built on the presences shared by both species. The fuzzy union between individual models, representing favourability for the presence of any of the two species, was compared with another favourabilitymodel based on the presences of either or both of them. The fuzzy intersections between favourability for each species and the complementary of favourability for the other (corresponding to the logical operation “A and not B”) were compared with models of exclusive presence of one species versus the exclusive presence of the other. The results of modelling combined species data were highly similar to those of fuzzy logic operations between individual models, proving fuzzy logic and the favourability function valuable for comparative distribution modelling. We highlight several advantages of fuzzy logic over other forms of combining distribution models, including the possibility to combine multiple species models for management and conservation planning.

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In this thesis we discuss in what ways computational logic (CL) and data science (DS) can jointly contribute to the management of knowledge within the scope of modern and future artificial intelligence (AI), and how technically-sound software technologies can be realised along the path. An agent-oriented mindset permeates the whole discussion, by stressing pivotal role of autonomous agents in exploiting both means to reach higher degrees of intelligence. Accordingly, the goals of this thesis are manifold. First, we elicit the analogies and differences among CL and DS, hence looking for possible synergies and complementarities along 4 major knowledge-related dimensions, namely representation, acquisition (a.k.a. learning), inference (a.k.a. reasoning), and explanation. In this regard, we propose a conceptual framework through which bridges these disciplines can be described and designed. We then survey the current state of the art of AI technologies, w.r.t. their capability to support bridging CL and DS in practice. After detecting lacks and opportunities, we propose the notion of logic ecosystem as the new conceptual, architectural, and technological solution supporting the incremental integration of symbolic and sub-symbolic AI. Finally, we discuss how our notion of logic ecosys- tem can be reified into actual software technology and extended towards many DS-related directions.

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In Prior Analytics 1.1–22, Aristotle develops his proof system of non-modal and modal propositions. This system is given in the language of propositions, and Aristotle is concerned with establishing some properties and relations that the expressions of this language enjoy. However, modern scholarship has found some of his results inconsistent with positions defended elsewhere. The set of rules of inference of this system has also caused perplexity: there does not seem to be a single interpretation that validates all the rules which Aristotle is explicitly committed to using in his proofs. Some commentators have argued that these and other problems cannot be successfully addressed from the viewpoint of the traditional, ‘first-order’ interpretation of Aristotle’s syllogistic, whereby propositions are taken to involve quantification over individuals only. Accordingly, this interpretation not only is inadequate for formal analysis, but also stems from a misunderstanding of Aristotle’s ideas about quantification. On the contrary, in this study I purport to vindicate the adequacy and plausibility of the first-order interpretation. Together with some assumptions about the language of propositions and an appropriate regimentation, the first-order interpretation yields promising solutions to many of the problems raised by the modal syllogistic. Thus, I present a reconstruction of the language of propositions and a formal interpretation thereof which will prove respectful and responsive to most of the views endorsed by Aristotle in the ‘modal’ chapters of the Analytics.

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This dissertation investigates the relations between logic and TCS in the probabilistic setting. It is motivated by two main considerations. On the one hand, since their appearance in the 1960s-1970s, probabilistic models have become increasingly pervasive in several fast-growing areas of CS. On the other, the study and development of (deterministic) computational models has considerably benefitted from the mutual interchanges between logic and CS. Nevertheless, probabilistic computation was only marginally touched by such fruitful interactions. The goal of this thesis is precisely to (start) bring(ing) this gap, by developing logical systems corresponding to specific aspects of randomized computation and, therefore, by generalizing standard achievements to the probabilistic realm. To do so, our key ingredient is the introduction of new, measure-sensitive quantifiers associated with quantitative interpretations. The dissertation is tripartite. In the first part, we focus on the relation between logic and counting complexity classes. We show that, due to our classical counting propositional logic, it is possible to generalize to counting classes, the standard results by Cook and Meyer and Stockmeyer linking propositional logic and the polynomial hierarchy. Indeed, we show that the validity problem for counting-quantified formulae captures the corresponding level in Wagner's hierarchy. In the second part, we consider programming language theory. Type systems for randomized \lambda-calculi, also guaranteeing various forms of termination properties, were introduced in the last decades, but these are not "logically oriented" and no Curry-Howard correspondence is known for them. Following intuitions coming from counting logics, we define the first probabilistic version of the correspondence. Finally, we consider the relationship between arithmetic and computation. We present a quantitative extension of the language of arithmetic able to formalize basic results from probability theory. This language is also our starting point to define randomized bounded theories and, so, to generalize canonical results by Buss.

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In this work, we develop a randomized bounded arithmetic for probabilistic computation, following the approach adopted by Buss for non-randomized computation. This work relies on a notion of representability inspired by of Buss' one, but depending on a non-standard quantitative and measurable semantic. Then, we establish that the representable functions are exactly the ones in PPT. Finally, we extend the language of our arithmetic with a measure quantifier, which is true if and only if the quantified formula's semantic has measure greater than a given threshold. This allows us to define purely logical characterizations of standard probabilistic complexity classes such as BPP, RP, co-RP and ZPP.

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To detect the presence of male DNA in vaginal samples collected from survivors of sexual violence and stored on filter paper. A pilot study was conducted to evaluate 10 vaginal samples spotted on sterile filter paper: 6 collected at random in April 2009 and 4 in October 2010. Time between sexual assault and sample collection was 4-48hours. After drying at room temperature, the samples were placed in a sterile envelope and stored for 2-3years until processing. DNA extraction was confirmed by polymerase chain reaction for human β-globin, and the presence of prostate-specific antigen (PSA) was quantified. The presence of the Y chromosome was detected using primers for sequences in the TSPY (Y7/Y8 and DYS14) and SRY genes. β-Globin was detected in all 10 samples, while 2 samples were positive for PSA. Half of the samples amplified the Y7/Y8 and DYS14 sequences of the TSPY gene and 30% amplified the SRY gene sequence of the Y chromosome. Four male samples and 1 female sample served as controls. Filter-paper spots stored for periods of up to 3years proved adequate for preserving genetic material from vaginal samples collected following sexual violence.

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The models of teaching social sciences and clinical practice are insufficient for the needs of practical-reflective teaching of social sciences applied to health. The scope of this article is to reflect on the challenges and perspectives of social science education for health professionals. In the 1950s the important movement bringing together social sciences and the field of health began, however weak credentials still prevail. This is due to the low professional status of social scientists in health and the ill-defined position of the social sciences professionals in the health field. It is also due to the scant importance attributed by students to the social sciences, the small number of professionals and the colonization of the social sciences by the biomedical culture in the health field. Thus, the professionals of social sciences applied to health are also faced with the need to build an identity, even after six decades of their presence in the field of health. This is because their ambivalent status has established them as a partial, incomplete and virtual presence, requiring a complex survival strategy in the nebulous area between social sciences and health.

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Lutein (LT) is a carotenoid obtained by diet and despite its antioxidant activity had been biochemically reported, few studies are available concerning its influence on the expression of antioxidant genes. The expression of 84 genes implicated in antioxidant defense was quantified using quantitative reverse transcription polymerase chain reaction array. DNA damage was measured by comet assay and glutathione (GSH) and thiobarbituric acid reactive substances (TBARS) were quantified as biochemical parameters of oxidative stress in mouse kidney and liver. cDDP treatment reduced concentration of GSH and increased TBARS, parameters that were ameliorated in treatment associated with LT. cDDP altered the expression of 32 genes, increasing the expression of GPx2, APC, Nqo1 and CCs. LT changed the expression of 37 genes with an induction of 13 mainly oxygen transporters. In treatments associating cDDP and LT, 30 genes had their expression changed with a increase of the same genes of the cDDP treatment alone. These results suggest that LT might act scavenging reactive species and also inducing the expression of genes related to a better antioxidant response, highlighting the improvement of oxygen transport. This improved redox state of the cell through LT treatment could be related to the antigenotoxic and antioxidant effects observed.

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A miniaturised gas analyser is described and evaluated based on the use of a substrate-integrated hollow waveguide (iHWG) coupled to a microsized near-infrared spectrophotometer comprising a linear variable filter and an array of InGaAs detectors. This gas sensing system was applied to analyse surrogate samples of natural fuel gas containing methane, ethane, propane and butane, quantified by using multivariate regression models based on partial least square (PLS) algorithms and Savitzky-Golay 1(st) derivative data preprocessing. The external validation of the obtained models reveals root mean square errors of prediction of 0.37, 0.36, 0.67 and 0.37% (v/v), for methane, ethane, propane and butane, respectively. The developed sensing system provides particularly rapid response times upon composition changes of the gaseous sample (approximately 2 s) due the minute volume of the iHWG-based measurement cell. The sensing system developed in this study is fully portable with a hand-held sized analyser footprint, and thus ideally suited for field analysis. Last but not least, the obtained results corroborate the potential of NIR-iHWG analysers for monitoring the quality of natural gas and petrochemical gaseous products.

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Dipyrone (metamizole) is an analgesic pro-drug used to control moderate pain. It is metabolized in two major bioactive metabolites: 4-methylaminoantipyrine (4-MAA) and 4-aminoantipyrine (4-AA). The aim of this study was to investigate the participation of peripheral CB1 and CB2 cannabinoid receptors activation in the anti-hyperalgesic effect of dipyrone, 4-MAA or 4-AA. PGE2 (100ng/50µL/paw) was locally administered in the hindpaw of male Wistar rats, and the mechanical nociceptive threshold was quantified by electronic von Frey test, before and 3h after its injection. Dipyrone, 4-MAA or 4-AA was administered 30min before the von Frey test. The selective CB1 receptor antagonist AM251, CB2 receptor antagonist AM630, cGMP inhibitor ODQ or KATP channel blocker glibenclamide were administered 30min before dipyrone, 4-MAA or 4-AA. The antisense-ODN against CB1 receptor expression was intrathecally administered once a day during four consecutive days. PGE2-induced mechanical hyperalgesia was inhibited by dipyrone, 4-MAA, and 4-AA in a dose-response manner. AM251 or ODN anti-sense against neuronal CB1 receptor, but not AM630, reversed the anti-hyperalgesic effect mediated by 4-AA, but not by dipyrone or 4-MAA. On the other hand, the anti-hyperalgesic effect of dipyrone or 4-MAA was reversed by glibenclamide or ODQ. These results suggest that the activation of neuronal CB1, but not CB2 receptor, in peripheral tissue is involved in the anti-hyperalgesic effect of 4-aminoantipyrine. In addition, 4-methylaminoantipyrine mediates the anti-hyperalgesic effect by cGMP activation and KATP opening.

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The present study analyzed metallothionein (MT) excretion from liver to bile in Nile Tilapia (Oreochromis niloticus) exposed to sub-lethal copper concentrations (2mgL(-1)) in a laboratory setting. MTs in liver and bile were quantified by spectrophotometry after thermal incubation and MT metal-binding profiles were characterized by size exclusion high performance liquid chromatography coupled to ICP-MS (SEC-HPLC-ICP-MS). Results show that liver MT is present in approximately 250-fold higher concentrations than bile MT in non-exposed fish. Differences between the MT profiles from the control and exposed group were observed for both matrices, indicating differential metal-binding behavior when comparing liver and bile MT. This is novel data regarding intra-organ MT comparisons, since differences between organs are usually present only with regard to quantification, not metal-binding behavior. Bile MT showed statistically significant differences between the control and exposed group, while the same did not occur with liver MT. This indicates that MTs synthesized in the liver accumulate more slowly than MTs excreted from liver to bile, since the same fish presented significantly higher MT levels in liver when compared to bile. We postulate that bile, although excreted in the intestine and partially reabsorbed by the same returning to the liver, may also release MT-bound metals more rapidly and efficiently, which may indicate an efficient detoxification route. Thus, we propose that the analysis of bile MTs to observe recent metal exposure may be more adequate than the analysis of liver MTs, since organism responses to metals are more quickly observed in bile, although further studies are necessary.

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Our objective was to investigate spinal cord (SC) atrophy in amyotrophic lateral sclerosis (ALS) patients, and to determine whether it correlates with clinical parameters. Forty-three patients with ALS (25 males) and 43 age- and gender-matched healthy controls underwent MRI on a 3T scanner. We used T1-weighted 3D images covering the whole brain and the cervical SC to estimate cervical SC area and eccentricity at C2/C3 level using validated software (SpineSeg). Disease severity was quantified with the ALSFRS-R and ALS Severity scores. SC areas of patients and controls were compared with a Mann-Whitney test. We used linear regression to investigate association between SC area and clinical parameters. Results showed that mean age of patients and disease duration were 53.1 ± 12.2 years and 34.0 ± 29.8 months, respectively. The two groups were significantly different regarding SC areas (67.8 ± 6.8 mm² vs. 59.5 ± 8.4 mm², p < 0.001). Eccentricity values were similar in both groups (p = 0.394). SC areas correlated with disease duration (r = - 0.585, p < 0.001), ALSFRS-R score (r = 0.309, p = 0.044) and ALS Severity scale (r = 0.347, p = 0.022). In conclusion, patients with ALS have SC atrophy, but no flattening. In addition, SC areas correlated with disease duration and functional status. These data suggest that quantitative MRI of the SC may be a useful biomarker in the disease.

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It is well known that long term use of shampoo causes damage to human hair. Although the Lowry method has been widely used to quantify hair damage, it is unsuitable to determine this in the presence of some surfactants and there is no other method proposed in literature. In this work, a different method is used to investigate and compare the hair damage induced by four types of surfactants (including three commercial-grade surfactants) and water. Hair samples were immersed in aqueous solution of surfactants under conditions that resemble a shower (38 °C, constant shaking). These solutions become colored with time of contact with hair and its UV-vis spectra were recorded. For comparison, the amount of extracted proteins from hair by sodium dodecyl sulfate (SDS) and by water were estimated by the Lowry method. Additionally, non-pigmented vs. pigmented hair and also sepia melanin were used to understand the washing solution color and their spectra. The results presented herein show that hair degradation is mostly caused by the extraction of proteins, cuticle fragments and melanin granules from hair fiber. It was found that the intensity of solution color varies with the charge density of the surfactants. Furthermore, the intensity of solution color can be correlated to the amount of proteins quantified by the Lowry method as well as to the degree of hair damage. UV-vis spectrum of hair washing solutions is a simple and straightforward method to quantify and compare hair damages induced by different commercial surfactants.

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Chlorophenylpiperazines (CPP) are psychotropic drugs used in nightclub parties and are frequently used in a state of sleep deprivation, a condition which can potentiate the effects of psychoactive drugs. This study aimed to investigate the effects of sleep deprivation and sleep rebound (RB) on anxiety-like measures in mCPP-treated mice using the open field test. We first optimized our procedure by performing dose-effect curves and examining different pretreatment times in naïve male Swiss mice. Subsequently, a separate cohort of mice underwent paradoxical sleep deprivation (PSD) for 24 or 48h. In the last experiment, immediately after the 24h-PSD period, mice received an injection of saline or mCPP, but their general activity was quantified in the open field only after the RB period (24 or 48h). The dose of 5mgmL(-1) of mCPP was the most effective at decreasing rearing behavior, with peak effects 15min after injection. PSD decreased locomotion and rearing behaviors, thereby inhibiting a further impairment induced by mCPP. Plasma concentrations of mCPP were significantly higher in PSD 48h animals compared to the non-PSD control group. Twenty-four hours of RB combined with mCPP administration produced a slight reduction in locomotion. Our results show that mCPP was able to significantly change the behavior of naïve, PSD, and RB mice. When combined with sleep deprivation, there was a higher availability of drug in plasma levels. Taken together, our results suggest that sleep loss can enhance the behavioral effects of the potent psychoactive drug, mCPP, even after a period of rebound sleep.

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Crotamine is one of the main constituents of the venom of the South American rattlesnake Crotalus durissus terrificus. Here we sought to investigate the inflammatory and toxicological effects induced by the intrahippocampal administration of crotamine isolated from Crotalus whole venom. Adult rats received an intrahippocampal infusion of crotamine or vehicle and were euthanized 24 h or 21 days after infusion. Plasma and brain tissue were collected for biochemical analysis. Complete blood count, creatinine, urea, glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), creatine-kinase (CK), creatine kinase-muscle B (CK-MB) and oxidative parameters (assessed by DNA damage and micronucleus frequency in leukocytes, lipid peroxidation and protein carbonyls in plasma and brain) were quantified. Unpaired and paired t-tests were used for comparisons between saline and crotamine groups, and within groups (24 h vs. 21 days), respectively. After 24 h crotamine infusion promoted an increase of urea, GOT, GPT, CK, and platelets values (p ≤ 0.01), while red blood cells, hematocrit and leukocytes values decreased (p ≤ 0.01). Additionally, 21 days after infusion crotamine group showed increased creatinine, leukocytes, TBARS (plasma and brain), carbonyl (plasma and brain) and micronucleus compared to the saline-group (p ≤ 0.01). Our findings show that crotamine infusion alter hematological parameters and cardiac markers, as well as oxidative parameters, not only in the brain, but also in the blood, indicating a systemic pro-inflammatory and toxicological activity. A further scientific attempt in terms of preserving the beneficial activity over toxicity is required.