717 resultados para Rodrick Dixon Gently
Resumo:
First-order temporal logic is a concise and powerful notation, with many potential applications in both Computer Science and Artificial Intelligence. While the full logic is highly complex, recent work on monodic first-order temporal logics has identified important enumerable and even decidable fragments. In this paper, we develop a clausal resolution method for the monodic fragment of first-order temporal logic over expanding domains. We first define a normal form for monodic formulae and then introduce novel resolution calculi that can be applied to formulae in this normal form. We state correctness and completeness results for the method. We illustrate the method on a comprehensive example. The method is based on classical first-order resolution and can, thus, be efficiently implemented.
Resumo:
Explorar as lições aprendidas na organização é uma tarefa relevante na gestão do conhecimento, pois a lição aprendida é um instrumento de conhecimento existencial, oriundo de experiência, positiva ou negativa, motivada durante a execução ou observação de fenômenos nas atividades e processos da organização, que, quando explicitado ou compartilhado, permite a elevação do conhecimento individual e, conseqüentemente, o aumento da inteligência organizacional. Estudos recentes e a literatura mostram que o compartilhamento e a transferência de conhecimento estão em estágio aquém dos resultados efetivos observados, mesmo com altos investimentos em projetos de gestão e em ferramentas de tecnologia de informação. Este trabalho estuda a gestão de Lições Aprendidas na organização sob uma perspectiva de como os mecanismos de compartilhamento e transferência de conhecimento podem promover uma gestão dinâmica de Lições Aprendidas, visando diminuir essa lacuna. Utiliza, como base conceitual, os ciclos de aprendizagem propostos por Stewhart e Kolb, por exemplo, empregados em processos de gestão de melhorias nas organizações. Também, foram estudados modelos de gestão de compartilhamento e transferência de conhecimento, de diversas fontes relevantes, tais como, Szulanski, Argyris e Dixon, a partir da análise dos seus fatores-chaves e do levantamento de mecanismos de comunicação, interpessoais e eletrônicos, aplicáveis ao contexto do estudo. O quadro teórico gerado serviu como protocolo para ser aplicado em pesquisa de campo, através do método de estudo de caso, em três empresas, indústrias brasileiras competitivas, tidas como sólidas, bem sucedidas, inovadoras e líderes em seus mercados de atuação, entre outros atributos que favorecem o escopo deste trabalho. Buscou-se identificar a replicação da teoria e o grau de suficiência e de eficiência dos mecanismos de “capilarização” das Lições Aprendidas – metáfora criada, no sentido de que, se a gestão das Lições Aprendidas for “capilar”, ou seja, conseguir chegar a todos os pontos da organização, aumenta-se o potencial de aproveitamento dos benefícios da exploração do conteúdo delas. Assim, se tem potencial para melhorar o desempenho da organização, objetivo chave da gestão do conhecimento.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
This study compared pressure and thermal thresholds after administration of three opioids in eight cats. Pressure stimulation was performed via a bracelet taped around the forearm. Three ball-bearings were advanced against the forearm by inflation of a modified blood pressure bladder. Pressure in the cuff was recorded at the end point (leg shake and head turn). Thermal threshold was tested as previously reported using a heated probe held against the thorax [Dixon et al. (2002) Research in Veterinary Science, 72, 205]. After baseline recordings, each cat received subcutaneous methadone 0.2 mg/kg, morphine 0.2 mg/kg, buprenorphine 0.02 mg/kg or saline 0.3 mL in a four period cross-over study. Measurements were made at 15, 30, 45 min and 1, 2, 3, 4, 8, 12 and 24 h after the injection. Data were analysed by ANOVA (P < 0.05). There were no significant changes in thresholds after saline. Thermal threshold increased at 45 min after buprenorphine (maximum 2.8 +/- 3 degrees C), 1-3 h after methadone (maximum 3.4 +/- 1.9 degrees C) and 45 min to 1 h (maximum 3.4 +/- 2 degrees C) after morphine. Pressure threshold increased 30-45 min (maximum 238 +/- 206 mmHg) after buprenorphine, 45-60 min after methadone (maximum 255 +/- 232 mmHg) and 45-60 min and 3-6 h (maximum 255 +/- 232 mmHg) after morphine. Morphine provided the best analgesia, and methadone appears a promising alternative. Buprenorphines limited effect was probably related to the subcutaneous route of administration. Previously, buprenorphine has produced much greater effects when given by other routes.
Resumo:
This thesis deals with the sedimentological/stratigraphic and structural evolution of the sedimentary rocks that occur in the NW continental border of the Potiguar Basin. These rocks are well exposed along coastal cliffs between the localities of Lagoa do Mato and Icapuí, Ceará State (NE Brazil). The sedimentological/stratigraphic study involved, at the outcrop scale, detailed facies descriptions, profile mapping of the vertical succession of different beds, and columnar sections displaying inferred lateral relationships. The approach was complemented by granulometric and petrographic analyses, including the characterization of heavy mineral assemblages. The data set allowed to recognize two kinds of lithological units, a carbonate one of very restricted occurrence at the base of the cliffs, and three younger, distinct siliciclastic units, that predominate along the cliffs, in vertical and lateral extent. The carbonate rocks were correlated to the late Cretaceous Jandaíra Formation, which is covered by the siliciclastic Barreiras Formation. The Barreiras Formation occurs in two distinct structural settings, the usual one with nondeformed, subhorizontal strata, or as tilted beds, affected by strong deformation. Two lithofacies were recognized, vertically arranged or in fault contacts. The lower facies is characterized by silty-argillaceous sandstones with low-angle cross bedding; the upper facies comprises medium to coarse grained sandstones, with conglomeratic layers. The Tibau Formation (medium to coarse-grained sandstones with argillite intercalations) occurs at the NW side of the studied area, laterally interlayered with the Barreiras Formation. Eolic sediments correlated to the Potengi Formation overly the former units, either displaying an angular unconformity, or simply an erosional contact (stratigraphic unconformity). Outstanding structural features, identified in the Barreiras Formation, led to characterize a neocenozoic stress field, which generated faults and folds and/or reactivated older structures in the subjacent late cretaceous (to paleogene, in the offshore basin) section. The structures recognized in the Barreiras Formation comprise two distinct assemblages, namely a main extensional deformation between the localities of Ponta Grossa and Redonda, and a contractional style (succeeded by oblique extensional structures) at Vila Nova. In the first case, the structural assemblage is dominated by N-S (N±20°Az) steep to gently-dipping extensional faults, displaying a domino-style or listric geometry with associated roll-over structures. This deformation pattern is explained by an E-W/WNW extension, contemporaneous with deposition of the upper facies of the Barreiras Formation, during the time interval Miocene to Pleistocene. Strong rotation of blocks and faults generated low-angle distensional faults and, locally, subvertical bedding, allowing to estimate very high strain states, with extension estimates varying between 40% up to 200%. Numerous detachment zones, parallel to bedding, help to acommodate this intense deformation. The detachment surfaces and a large number of faults display mesoscopic features analoguous to the ones of ductile shear zones, with development of S-C fabrics, shear bands, sigmoidal clasts and others, pointing to a hydroplastic deformation regime in these cases. Local occurrences of the Jandaíra limestone are controled by extensional faults that exhume the pre-Barreiras section, including an earlier event with N-S extension. Finally, WNWtrending extensional shear zones and faults are compatible with the Holocene stress field along the present continental margin. In the Vila Nova region, close to Icapuí, gentle normal folds with fold hinges shallowly pluging to SSW affect the lower facies of the Barreiras Formation, displaying an incipient dissolution cleavage associated with an extension lineation at high rake (a S>L fabric). Deposition of the upper facies siliciclastics is controlled by pull-apart graben structures, bordered by N-NE-trending sinistral-normal shear zones and faults, characterizing an structural inversion. Microstructures are compatible with tectonic deformation of the sedimentary pile, burried at shallow depths. The observed features point to high pore fluid pressures during deformation of the sediments, producing hydroplastic structures through mechanisms of granular flow. Such structures are overprinted by microfractures and microfaults (an essentially brittle regime), tracking the change to microfracturing and frictional shear mechanisms accompanying progressive dewatering and sediment lithification. Correlation of the structures observed at the surface with those present at depth was tested through geophysical data (Ground Penetrating Radar, seismics and a magnetic map). EW and NE-trending lineaments are observed in the magnetic map. The seismic sections display several examples of positive flower structures which affect the base of the cretaceous sediments; at higher stratigraphic levels, normal components/slips are compatible with the negative structural inversion characterized at the surface. Such correlations assisted in proposing a structural model compatible with the regional tectonic framework. The strong neogenepleistocene deformation is necessarily propagated in the subsurface, affecting the late cretaceous section (Açu and Jandaíra formations), wich host the hydrocarbon reservoirs in this portion of the Potiguar Basin. The proposed structural model is related to the dextral transcurrent/transform deformation along the Equatorial Margin, associated with transpressive terminations of E-W fault zones, or at their intersections with NE-trending lineaments, such as the Ponta Grossa-Fazenda Belém one (the LPGFB, itself controlled by a Brasiliano-age strike-slip shear zone). In a first step (and possibly during the late Cretaceous to Paleogene), this lineament was activated under a sinistral transpressional regime (antithetic to the main dextral deformation in the E-W zones), giving way to the folds in the lower facies of the Barreiras Formation, as well as the positive flower structures mapped through the seismic sections, at depth. This stage was succeeded (or was penecontemporaneous) by the extensional structures related to a (also sinistral) transtensional movement stage, associated to volcanism (Macau, Messejana) and thermal doming processes during the Neogene-Pleistocene time interval. This structural model has direct implications to hydrocarbon exploration and exploitation activities at this sector of the Potiguar Basin and its offshore continuation. The structure of the reservoirs at depth (Açu Formation sandstones of the post-rift section) may be controlled (or at least, strongly influenced) by the deformation geometry and kinematics characterized at the surface. In addition, the deformation event recognized in the Barreiras Formation has an age close to the one postulated for the oil maturation and migration in the basin, between the Oligocene to the Miocene. In this way, the described structural cenario represents a valid model to understand the conditions of hydrocarbon transport and acummulation through space openings, trap formation and destruction. This model is potentially applicable to the NW region of the Potiguar Basin and other sectors with a similar structural setting, along the brazilian Equatorial Atlantic Margin
Resumo:
I thank to my advisor, João Marcos, for the intellectual support and patience that devoted me along graduate years. With his friendship, his ability to see problems of the better point of view and his love in to make Logic, he became a great inspiration for me. I thank to my committee members: Claudia Nalon, Elaine Pimentel and Benjamin Bedregal. These make a rigorous lecture of my work and give me valuable suggestions to make it better. I am grateful to the Post-Graduate Program in Systems and Computation that accepted me as student and provided to me the propitious environment to develop my research. I thank also to the CAPES for a 21 months fellowship. Thanks to my research group, LoLITA (Logic, Language, Information, Theory and Applications). In this group I have the opportunity to make some friends. Someone of them I knew in my early classes, they are: Sanderson, Haniel and Carol Blasio. Others I knew during the course, among them I’d like to cite: Patrick, Claudio, Flaulles and Ronildo. I thank to Severino Linhares and Maria Linhares who gently hosted me at your home in my first months in Natal. This couple jointly with my colleagues of student flat Fernado, Donátila and Aline are my nuclear family in Natal. I thank my fiancée Luclécia for her precious a ective support and to understand my absence at home during my master. I thank also my parents Manoel and Zenilda, my siblings Alexandre, Paulo and Paula.Without their confidence and encouragement I wouldn’t achieve success in this journey. If you want the hits, be prepared for the misses Carl Yastrzemski
Resumo:
To evaluate a prototype pressure stimulus device for use in the cat and to compare with a known thermal threshold device.Eight healthy adult cats weighing between 3.0 and 4.9 kg.Pressure stimulation was given via a plastic bracelet taped around the forearm. Three 2.4 mm diameter ball bearings, in a 10-mm triangle, were advanced against the craniolateral surface of the antebrachium by manual inflation of a modified blood pressure bladder. Pressure in the cuff was recorded at the end point (leg shake and head turn). Thermal threshold was also tested. Stimuli were stopped if they reached 55 degrees C or 450 mmHg without response. After four pressure and thermal threshold baselines, each cat received SC buprenorphine 0.01 mg kg(-1), carprofen 4 mg kg(-1) or saline 0.3 mL in a three period cross-over study with a 1-week interval. The investigator was blinded to the treatment. Measurements were made at 0.25. 0.5, 0.75, 1, 2, 3, 4, 6, 8, and 24 hours after injection. Data were analyzed by using ANOVA.There were no significant changes in thermal or pressure threshold after administration of saline or carprofen, but thermal threshold increased from 60 minutes until 8 hours after administration of buprenorphine (p < 0.05). The maximum increase in threshold from baseline (Delta T-max) was 3.5 +/- 3.1 degrees C at 2 hours. Pressure threshold increased 2 hours after administration of buprenorphine (p < 0.05) when the increase in threshold above baseline (Delta P-max) was 162 +/- 189 mmHg.This pressure device resulted in thresholds that were affected by analgesic treatment in a similar manner but to a lesser degree than the thermal method. Pressure stimulation may be a useful additional method for analgesic studies in cats.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Alendronate is a known inhibitor of root resorption and the development of alendronate paste would enhance its utilization as intracanal medication. Therefore, this study aimed to investigate the biocompatibility of experimental alendronate paste in subcutaneous tissue of rats, for utilization in teeth susceptible to root resorption. The study was conducted on 15 male rats, weighing similar to 180-200 grams. The rats' dorsal regions were submitted to one incision on the median region and, laterally to the incision, the subcutaneous tissue was raised and gently dissected for introduction of two tubes, in each rat. The tubes were sealed at one end with gutta-percha and taken as control. The tubes were filled with experimental alendronate paste. The animals were killed at 7, 15 and 45 days after surgery and the specimens were processed in laboratory. The histological sections were stained with hematoxylin-eosin and analyzed by light microscopy. Scores were assigned to the in. ammatory process and statistically compared by the Tukey test (P < 0.05). Alendronate paste promoted severe inflammation process at 7 days, with statistically significant difference compared to the control (P < 0.05%). However, at 15 days, there was a regression of in. ammation and the presence of connective tissue with collagen fibers, fibroblasts and blood vessels was observed. After 45 days, it was observed the presence of well-organized connective tissue, with collagen fibers and fibroblasts, and few in. ammatory cells. No statistical difference was observed between the control and experimental paste at 15 and 45 days. The experimental alendronate paste was considered biocompatible with subcutaneous tissue of rat.
Resumo:
Objectives: The aim of this in vitro study was to assess the effects of saliva substitutes (modified with respect to calcium, phosphates, and fluorides) in combination with a high-concentrated fluoride toothpaste on demineralised dentin.Methods: Before and after demineralisation of bovine dentin specimens (subsurface lesions; 37 degrees C, pH 5.0, 5 d), one-quarter of each specimen's surface was covered with nail varnish (control of sound/demineralised tissue). Subsequently, specimens were exposed to original Saliva natura (saturation with respect to octacalciumphosphate [S(OCP)]: 0.03; SN 0), or to three lab-produced Saliva natura modifications (S(OCP): 1, 2, and 3; SN 1-3) for 2 and 5 weeks (37 degrees C). An aqueous solution (S(OCP): 2.5) served as positive control (PC). Two times daily (2 min each), Duraphat toothpaste (5000 ppm F(-); Colgate)/saliva substitute slurry (ratio 1:3) was applied gently. Differences in mineral losses (Delta Delta Z) and lesion depths (Delta LD) between values before and after exposure were microradiographically evaluated.Results: After both treatment periods specimens immersed in SN 0 revealed significantly higher mineral losses (lower Delta Delta Z values) and lesion depths (lower Delta LD) compared to PC (p < 0.05; ANOVA). After 5 weeks, specimens stored in SN 1 and 2 showed significantly higher mineral losses compared to PC (p < 0.05), while those stored in SN 3 showed similar results (p > 0.05). No differences in mineral loss could be observed between SN 2 and 3 (p > 0.05).Conclusions: Under the conditions of this limited protocol, the combination of Saliva natura solutions slightly saturated with respect to OCP in combination with a high-concentrated fluoride toothpaste enabled remineralisation of dentin in vitro. Crown Copyright (c) 2009 Published by Elsevier Ltd. All rights reserved.
Resumo:
Purpose: To evaluate clinically and microscopically the human pulp response when directly capped with an adhesive system or calcium hydroxide over short (9-12 days) and long (53-204 days) experimental periods. Materials and Methods: Fifty-one sound human premolars scheduled for orthodontic extraction, had their pulp horns gently exposed with a diamond point. Debris in the pulp wound was washed out with a sterile saline solution. The pulps were then capped with either an adhesive system (Scotchbond Multi-Purpose Plus) or calcium hydroxide. All teeth were subsequently restored with resin-based composite (Z-100) according to the manufacturer's instructions. After the experimental periods, the teeth were extracted and processed for light microscopic examination. Results: Short-term: the pulp tissue capped with SBMP-P exhibited dilated and congested blood vessels associated with a mo;derate inflammatory response and blanching of pulp cell nuclei. Long-term: no evidence of healing and bridge formation was observed. A persistent mild inflammatory pulp response was present. Micro-abscesses were detected in three cases associated with bacterial infiltration. Calcium hydroxide stimulated early pulp repair and dentin bridging which extended into the longest period.
Resumo:
Interferon regulatory factor 6 (IRF6) belongs to a family of nine transcription factors that share a highly conserved helix-turn-helix DNA-binding domain and a less conserved protein-binding domain. Most IRFs regulate the expression of interferon-alpha and -beta after viral infection(1), but the function of IRF6 is unknown. The gene encoding IRF6 is located in the critical region for the Van der Woude syndrome (VWS; OMIM 119300) locus at chromosome 1q32-q41 (refs 2,3). The disorder is an autosomal dominant form of cleft lip and palate with lip pits(4), and is the most common syndromic form of cleft lip or palate. Popliteal pterygium syndrome (PPS; OMIM 119500) is a disorder with a similar orofacial phenotype that also includes skin and genital anomalies(5). Phenotypic overlap(6) and linkage data(7) suggest that these two disorders are allelic. We found a nonsense mutation in IRF6 in the affected twin of a pair of monozygotic twins who were discordant for VWS. Subsequently, we identified mutations in IRF6 in 45 additional unrelated families affected with VWS and distinct mutations in 13 families affected with PPS. Expression analyses showed high levels of Irf6 mRNA along the medial edge of the fusing palate, tooth buds, hair follicles, genitalia and skin. Our observations demonstrate that haploinsufficiency of IRF6 disrupts orofacial development and are consistent with dominant-negative mutations disturbing development of the skin and genitalia.
Resumo:
Purpose: Interferon regulatory factor 6 encodes a member of the IRF family of transcription factors. Mutations in interferon regulatory factor 6 cause Van der Woude and popliteal pterygium syndrome, two related orofacial clefting disorders. Here, we compared and contrasted the frequency and distribution of exonic Mutations in interferon regulatory factor 6 between two large geographically distinct collections of families with Van der Woude and between one collection of families with popliteal pterygium syndrome. Methods: We performed direct sequence analysis of interferon regulatory factor 6 exons oil samples from three collections, two with Van der Woude and one with popliteal pterygium syndrome. Results: We identified mutations in interferon regulatory factor 6 exons in 68% of families in both Van der Woude collections and in 97% of families with popliteal pterygium syndrome. In sum, 106 novel disease-causing variants were found. The distribution of mutations in the interferon regulatory factor 6 exons in each collection was not random; exons 3, 4, 7, and 9 accounted for 80%. In the Van der Woude collections, the mutations were evenly divided between protein truncation and missense, whereas most mutations identified in the popliteal pterygium syndrome collection were missense. Further, the missense mutations associated with popliteal pterygium syndrome were localized significantly to exon 4, at residues that are predicted to bind directly to DNA. Conclusion: The nonrandom distribution of mutations in the interferon regulatory factor 6 exons suggests a two-tier approach for efficient mutation screens for interferon regulatory factor 6. The type and distribution of mutations are consistent with the hypothesis that Van der Woude is caused by haploinsufficiency of interferon regulatory factor 6. Oil the other hand, the distribution of popliteal pterygium syndrome-associated mutations suggests a different, though not mutually exclusive, effect oil interferon regulatory factor 6 function. Genet Med 2009:11(4):241-247.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
A model of nociceptive threshold determination was developed for evaluation of NSAID analgesia in cats. In a crossover study, eight cats received carprofen (4 mg/kg), buprenorphine (0.01 mg/kg) or saline (0.3 ml) subcutaneously before intradermal kaolin injection on the antebrachium to induce mild inflammation. Pressure thresholds were measured at the injected site using blunt-ended pins advanced by manual inflation of a bladder within a bracelet. Bladder pressure was recorded as threshold (PT) at the behavioural end point. Baseline PT were recorded before kaolin injection (time 0). PT was measured at 2-10 h intervals for 52 h. PT below the lower 95% confidence interval (CI) of baseline values indicated hyperalgesia. After saline, hyperalgesia was detected from 2-6 h, 22-26 h, and at 30 and 36 h. After carprofen, PT remained within the 95% CI. After buprenorphine, PT remained within the 95% CI except at 2 h. Carprofen and to some extent buprenorphine, prevented inflammatory hyperalgesia. (C) 2007 Elsevier Ltd. All rights reserved.