45 resultados para information storage and retrieval systems


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The protonation of 4-dimethylaminobenzylidenepyruvate (DMBP) and 2-chloro-4-dimethylaminobenzylidenepyruvate (2-CI-DMBP) and their complex formation with Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II) and Al(III) have been studied by potentiometric and spectrophotometric methods at 25 °C and ionic strength 0.500 M, held with sodium perchlorate. The stability order found for 1 :1 complexes of both ligands is Al(III) > Cu(II) > Pb(II) > Ni(II) > Zn(II) > Co(II) > Cd(II) > Mn(II). The stability changes move in the same direction as the pKa of the ligands. The results are compared with literature values reported for metal ion pyruvate systems. Thermodynamic stabilities of ternary complexes formed in Cu(II)-B-L- systems, where B = 2,2′-bipyridyl (bipy), ethylenediamine or glycinate and L = DMBP or 2-CI-DMBP, were also determined. The Cu(bipy)L+ species are more stable than would be expected on purely statistical grounds. The importance of the :t system associated with bipy on the enhanced stability of its mixed ligand complexes is stressed. Analytical applications of the investigated ligands are outlined.

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To examine the evolution of endurance-exercise behaviour, we have selectively bred four replicate lines of laboratory mice (Mus domesticus) for high voluntary wheel running ('high runner' or HR lines), while also maintaining four non-selected control (C) lines. By generation 16, HR mice ran ∼2.7-fold more than C mice, mainly by running faster (especially in females), a differential maintained through subsequent generations, suggesting an evolutionary limit of unknown origin. We hypothesized that HR mice would have higher glycogen levels before nightly running, show greater depletion of those depots during their more intense wheel running, and have increased glycogen synthase activity and GLUT-4 protein in skeletal muscle. We sampled females from generation 35 at three times (photophase 07:00 h-19:00 h) during days 5-6 of wheel access, as in the routine selection protocol: Group 1, day 5, 16:00 h-17:30 h, wheels blocked from 13:00 h; Group 2, day 6, 02:00 h-03:30 h (immediately after peak running); and Group 3, day 6, 07:00 h-08:30 h. An additional Group 4, sampled 16:00 h-17:30 h, never had wheels. HR individuals with the mini-muscle phenotype (50% reduced hindlimb muscle mass) were distinguished for statistical analyses comparing C, HR normal, and HR mini. HR mini ran more than HR normal, and at higher speeds, which might explain why they have been favored by the selective-breeding protocol. Plasma glucose was higher in Group 1 than in Group 4, indicating a training effect (phenotypic plasticity). Without wheels, no differences in gastrocnemius GLUT-4 were observed. After 5 days with wheels, all mice showed elevated GLUT-4, but HR normal and mini were 2.5-fold higher than C. At all times and irrespective of wheel access, HR mini showed approximately three-fold higher [glycogen] in gastrocnemius and altered glycogen synthase activity. HR mini also showed elevated glycogen in soleus when sampled during peak running. All mice showed some glycogen depletion during nightly wheel running, in muscles and/or liver, but the magnitude of this depletion was not large and hence does not seem to be limiting to the evolution of even-higher wheel running.

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This work presents the Petri net-based modeling of an autonomous robot's navigation system used for the application of supplies in agriculture. The model was developed theoretically and implemented through the CPNTools software. It simulates the behavior of the robot, capturing environmental characteristics by means of sensors, making appropriate decisions, and forwarding them to the corresponding actuators. By exciting the model using CPNTools it is possible to simulate situations that the robot might undergo, without the need to expose it to real potentially dangerous situations. ©2009 IEEE.

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The cost of maintenance makes up a large part of total energy costs in ruminants. Metabolizable energy (ME) requirement for maintenance (MEm) is the daily ME intake that exactly balances heat energy (HE). The net energy requirement for maintenance (NEm) is estimated subtracting MEm from the HE produced by the processing of the diet. Men cannot be directly measured experimentally and is estimated by measuring basal metabolism in fasted animals or by regression measuring the recovered energy in fed animals. MEm and NEm usually, but not always, are expressed in terms of BW0.75. However, this scaling factor is substantially empirical and its exponent is often inadequate, especially for growing animals. MEm estimated by different feeding systems (AFRC, CNCPS, CSIRO, INRA, NRC) were compared by using dairy cattle data. The comparison showed that these systems differ in the approaches used to estimate MEm and for its quantification. The CSIRO system estimated the highest MEm, mostly because it includes a correction factor to increase ME as the feeding level increases. Relative to CSIRO estimates, those of NRC, INRA, CNCPS, and AFRC were on average 0.92, 0.86, 0.84, and 0.78, respectively. MEm is affected by the previous nutritional history of the animals. This phenomenon is best predicted by dynamic models, of which several have been published in the last decades. They are based either on energy flows or on nutrient flows. Some of the different approaches used were described and discussed.

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Influence of cutting instruments and The aim of this study was to analyze the hybrid layer in noncarious dentin prepared by different cutting instruments and restored with composite resin. The cavities were randomly prepared in 40 specimens using a high-speed diamond bur (KG Sorensen 1013) and an ultrasonic tip (CVDentus C22). The cavities were restored with composite resin by varying the adhesive system between the Adper™ Single Bond (2 x 1 system, primer+adhesive) and the Prompt L-Pop™ (3 x 1 system, self-etching). The restorations were hemisected longitudinally and analyzed in the SEM (Scanning electron microscopy) in order to evaluate the hybrid layer and resinous tags characteristics, using scores ranging from 1 to 6. The Pearson test revealed a high correlation coefficient and good significance levels for both intra- and inter-raters values (r=0.90). The data were statistically analyzed using the Mann-Whitney test (P≤0.05). A larger proportion of regular hybrid layers with numerous tags were observed in the dentin prepared using the high-speed diamond burs and restored with a 2 × 1 adhesive system. Alternatively, the 3 × 1 adhesive system promoted the generation of a thin hybrid layer with few tags. After preparation using an ultrasonic tip revealed few or no tags after the preparation and 2 × 1 or 3 × 1 adhesive system application. The high-speed diamond burs produced a dentin surface that was more favorable to restorative material adhesion than the ultrasonic tips, regardless of the adhesive system used.

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Modal analysis is widely approached in the classic theory of power systems modelling. This technique is also applied to model multiconductor transmission lines and their self and mutual electrical parameters. However, this methodology has some particularities and inaccuracies for specific applications, which are not clearly described in the technical literature. This study provides a brief review on modal decoupling applied in transmission line digital models and thereafter a novel and simplified computational routine is proposed to overcome the possible errors embedded by the modal decoupling in the simulation/ modelling computational algorithm. © The Institution of Engineering and Technology 2013.

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Research for acaricides with lower toxicity and impact on the environment has been intensified. An alternative would be the use of natural compounds or of synthetic products in lower concentrations than the ones sold commercially. Thus, this study describes the action of andiroba seed oil on the nuclei of the ovary and synganglion cells of Rhipicephalus sanguineus, and presents an analysis of the nuclear morphology of the nervous system cells of this tick species when exposed to permethrin. The results obtained showed that, although no changes have been observed in the genetic material of the ovary cells exposed to the andiroba oil, this compound, as well as permethrin, has neurotoxic action on the females of this species. The damages caused to the physiology of the synganglion, due to the loss of integrity of the genetic material, would result in the impairment of the metabolism of other systems of R. sanguineus ticks. © 2013 Elsevier Ltd.

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We have compared the results of the external irrigation technique with those of a double irrigation technique with continuous intermittent movement. Maximum thermal measurements were made in the cortical part of 10 samples of bovine ribs during osteotomy to simulate the preparation of a surgical bed for the installation of dental implants at a depth of 10 mm Twenty specimens were drilled for each group: external irrigation and continuous movement (control group 1, CG1); external irrigation and intermittent movement (control group 2, CG2); double irrigation and continuous movement (test group 1, TG1); and double irrigation and intermittent movement (test group 2, TG2). The double irrigation technique gave significantly better results regardless of the drilling movement used. Thermal increases between samples was 19.2% in group CG1, 10.4% in CG2, 5.4% in TG1, and 3.4% in TG2. The double irrigation technique produced a significantly smaller increase in temperature in the cortical bone during both types of drilling (p = 0.001), which illustrated its greater efficiency compared with that of the external irrigation technique. (C) 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Organizational environments are related to hierarchic levels existing in a determined organization, and they influence in the formal and informal flows origin and in their monitoring and/or extinction. Informational environments are a result of organizational environments, of which focus is information and knowledge. Information flows are a fundamental element to informational environments, in a way that there´s no informational environments if there´s no information flows. Informational flows are natural reflections from their environments, in terms of content and in the way they occur. This qualitative and quantitative research was developed in three stages, in a way to allow the comprehension of the phenomena related to information and knowledge environments and information flows that occur in the meat sector from the Province of Salamanca, Spain. We used Laurence Bardin´s ‘Analysis of Content’, more specifically the ‘Categorical Analysis’ technique to data analysis. As data collection procedure we accomplished a field research, applying a questionnaire as an intentional sample of the meat industries segment from the Province of Salamanca, Spain. From data tabulation and analysis, we infer that information environments and flows are relevant to these companies business development, as well as we emphasized the need of information and knowledge management deployment, in a way to insure organizational processes quality, industrial chain production and companies competition to conquer potential markets.

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In relation to the changes that mark the trajectory of libraries catalogs, this paper aims to describe the challenges that go beyond the current status of librarians, in relation to use of the on-line catalog as the main tool storage and retrieval of documentary information. Using literature specialized is intended to contribute to the discussion of the topic, in order to understand the challenges and prospects of using this important tool for search and information retrieval.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)