890 resultados para Hierarchical data, Multilevel models, Motor vehicle crashes, Transportation safety, Rural intersections


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The effects of postnatal amitraz exposure on physical and behavioral parameters were studied in Wistar rats, whose lactating dams received the pesticide (10 mg/Kg) orally on days 1, 4, 7, 10, 13, 16 and 19 of lactation; control dams received distilled water (1 ml/kg) on the same days. A total of 18 different litters (9 of them control and 9 experimental) born after a 21- day gestation were used. The results showed that the median effective time (ET50) for fur development, eye opening, testis descent and onset of the startle response were increased in rats postnatally exposed to amitraz (2.7, 15.1, 21.6 and 15.3 days, respectively) compared to those of the control pups (1.8, 14.0, 19.9 and 12.9 days, respectively). The ages of incisor eruption, total unfolding of the external ears, vaginal and ear opening and the time taken to perform the grasping hindlimb reflex were not affected by amitraz exposure. Pups from dams treated with amitraz during lactation took more time (in seconds) to perform the surface righting reflex on postnatal days (PND) 3 (25.0 ±2.0), 4 (12.3 ± 1.2) and 5 (8.7 ± 0.9) in relation to controls (10.6 ± 1.2; 4.5 ± 0.6 and 3.4 ± 0.4, respectively); the climbing response was not changed by amitraz. Postnatal amitraz exposure increased spontaneous motor activity of male and female pups in the open-field on PND 16 (140± 11)and 17(124± 12), and 16 (104±9), 17 (137 ± 9) and 18 (106 ± 8), respectively. Data on spontaneous motor activity of the control male and female pups were 59 ± 11 and 69 ± 10 for days 16 and 17 and 49 ± 9, 48 ± 7 and 56 ± 7 for days 16, 17 and 18, respectively. Some qualitative differences were also observed in spontaneous motor behavior; thus, raising the head, shoulder and pelvis matured one or two days later in the amitraz- treated offspring. Postnatal amitraz exposure did not change locomotion and rearing frequencies or immobility time in the open-field on PND 30, 60 and 90. The present findings indicate that postnatal exposure to amitraz caused transient developmental and behavioral changes in the exposed offspring and suggest that further investigation of the potential health risk of amitraz exposure to developing human and animal offsprings may be warranted.

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This paper presents the prototype of a low-cost terrestrial mobile mapping system (MMS) composed of a van, two digital video cameras, two GPS receivers, a notebook computer, and a sound frame synchronisation system. The imaging sensors are mounted as a stereo video camera on top of the vehicle together with the GPS antennae. The GPS receivers and the notebook computer are configured to record data referred to the vehicle position at a planned time interval. This position is subsequently transferred to the road images. This set of equipment and methods provide the opportunity to merge distinct techniques to make topographic maps and also to build georeferenced road image databases. Both vector maps and raster image databases, when integrated appropriately, can give spatial researchers and engineers a new technique whose application may realise better planning and analysis related to the road environment. The experimental results proved that the MMS developed at the São Paulo State University is an effective approach to inspecting road pavements, to map road marks and traffic signs, electric power poles, telephone booths, drain pipes, and many other applications important to people's safety and welfare. A small number of wad images have already been captured by the prototype as a consequence of its application in distinct projects. An efficient organisation of those images and the prompt access to them justify the need for building a georeferenced image database. By expanding it, both at the hardware and software levels, it is possible for engineers to analyse the entire road environment on their office computers.

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This work presents a branch-and-bound algorithm to solve the multi-stage transmission expansion planning problem. The well known transportation model is employed, nevertheless the algorithm can be extended to hybrid models or to more complex ones such as the DC model. Tests with a realistic power system were carried out in order to show the performance of the algorithm for the expansion plan executed for different time frames. © 2005 IEEE.

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A measurement of the underlying activity in scattering processes with pT scale in the GeV region is performed in proton-proton collisions at √ = 0.9 TeV, using data collected by the CMS experiment at the LHC. Charged particle production is studied with reference to the direction of a leading object, either a charged particle or a set of charged particles forming a jet. Predictions of several QCD-inspired models as implemented in PYTHIA are compared, after full detector simulation, to the data. The models generally predict too little production of charged particles with pseudorapidity {pipe}η{pipe} < 2, pT > 0.5 GeV/c, and azimuthal direction transverse to that of the leading object. © 2010 CERN for benefit of the CMS collaboration.

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At this time, each major automotive market bares its own standards and test procedures to regulate the vehicle green house gases emissions and, thus, fuel consumption. Hence, much are the ways to evaluate the overall efficiency of motor vehicles. The majority of such standards rely on dynamometer cycle tests that appraise only the vehicle as a whole, but fail to assess emissions for each component or sub-system. Once the amount of work generated by the power source of an ICE vehicle to overcome the driving resistance forces is proportional to the energy contained in the required amount of fuel, the power path of the vehicle can be straightforwardly modeled as a set of mechanical systems, and each sub-system evaluated for its share on the total fuel consumption and green house gases emission. This procedure enables the estimation of efficiency gains on the system due to improvement of particular elements on the vehicle's driveline. In this work a simple systematic mechanical model of an arbitrary smallsized hatch back was assembled and total required energy calculated for different regulatory cycles. All the modeling details of the energy balance throughout the system are presented. Afterward, each subsystem was investigated for its role on the fuel consumption and the generated emission quantified. Furthermore, the application of the modeling technique for different sets of sub-systems was introduced. Copyright © 2011 SAE International.

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Pós-graduação em Biofísica Molecular - IBILCE

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Pós-graduação em Ciência Animal - FMVA

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Pós-graduação em Odontologia - FOA