983 resultados para Head-On Collisions.


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L‟utilité de la théorie de la dissuasion est régulièrement remise en question pour expliquer la relation entre les peines et la criminalité puisque les propriétés objectives de la peine ne semblent pas affecter les taux de criminalité, les perceptions que s‟en font les individus et la récidive des délinquants. Trois limites conceptuelles des auteurs qui remettent en question la dissuasion sont soulevées. Premièrement, les unités spatiales utilisées sont des territoires sur lesquels plusieurs corps policiers sont en fonction. Il y a donc peu de chances que tous les citoyens présents soient exposés au même message pénal. Deuxièmement, les chercheurs ont mesuré le risque objectif d‟être arrêté à l‟aide d‟un ratio entre le nombre d‟arrestations et le nombre de crimes rapportés. Cette conceptualisation est problématique puisque les résultats d‟autres études suggèrent que les citoyens ont peu de connaissances des propriétés objectives et qu‟il serait, ainsi, intéressant de se référer aux stimuli dissuasifs pour conceptualiser la notion de risques. Troisièmement, pour plusieurs chercheurs, la délinquance est considérée comme une activité pour laquelle les délits impunis découlent du hasard. Pourtant, les délinquants utilisent fréquemment des stratégies pour éviter les autorités policières. Ils sont donc proactifs dans leur impunité. De ces limites découlent quatre propositions : 1) afin de détecter les réels effets des propriétés de la peine sur la criminalité, les territoires utilisés dans les études doivent représenter des juridictions sur lesquelles un seul corps policier opère; 2) afin de détecter les réels effets des propriétés de la peine sur la criminalité, les études doivent être effectuées avec des données provenant d‟une juridiction dans laquelle les activités de répression sont augmentées significativement par rapport à leur seuil antérieur et maintenue sur une période de temps suffisamment longue; 3) les stimuli dissuasifs observés doivent être considérés comme des expériences vicariantes ; 4) l‟impunité doit être définie comme étant une expérience recherchée par les délinquants. Deux études ont été réalisées dans le cadre de cette thèse. D‟abord, une étude a été réalisée à l‟aide de données issues des rapports policiers de collisions et des constats d‟infraction rendus. Les résultats montrent que l‟augmentation de la répression policière ii sur le territoire du Service de Police de la Ville de Montréal a fait diminuer le nombre de collisions. Au même moment, les collisions sont demeurées stables sur le territoire desservis par le Service de police de la Ville de Québec. Dans un deuxième temps, une étude perceptuelle a été réalisée avec un échantillon d‟étudiants universitaires. Les résultats démontrent des effets mitigés des stimuli dissuasifs sur les perceptions que se font les individus de leurs risques d‟être arrêté et sur leurs comportements délinquants. Chez les moins délinquants, les stimuli dissuasifs font augmenter la perception que les délinquants se font de leurs risques. Par contre, les plus motivés à commettre des délits de la route développent des stratégies en réaction aux opérations policières plutôt que d‟en craindre les représailles. Ces tactiques d‟évitement n‟assurent pas une impunité totale, ni une perception moins élevée des risques de recevoir une contravention, mais elles retardent le moment où le délinquant sera confronté à la punition.

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La loi mémorielle du 23 février 2005 a créé une grande controverse en France. Les historiens furent le fer de lance de cette opposition, tant cette loi heurtait les fondements même de leur profession. En effet, la loi de 2005 préconisait l’obligation pour ceux-ci d’enseigner le rôle positif de la colonisation française, ce qui contrevient à la liberté de pensée indispensable à la fonction de l’historien. Le présent mémoire analyse la réaction des historiens afin de cerner leurs positions et leur compréhension de la crise. Il porte un nouveau regard sur la crise mémorielle de 2005 et évalue les écrits et actions des historiens. Il s’avère que la crise fut plus complexe que l’interprétation que lui ont donnée les historiens. À cet égard, l’étude souligne l’importance de l’espace public dans la relation entre les communautés mémorielles et les historiens. A ce titre, l’école symbolise ce lieu de rencontre entre histoire et mémoire. Le mémoire examine aussi l’enseignement de l’histoire dans un milieu scolaire affecté par les tensions mémorielles. En réponse à ces débordements de mémoire, l’historien a un devoir de rigueur intellectuelle autant à l’école que dans l’espace public en général.

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Homogeneous dispersion of microemulsion containing palladium nanoparticles in scCO(2) is, for the first time, observed via sapphire window reactor and these particles show an unusual reluctance for double bond hydrogenation of citral aldehyde at hydrophobic end rather than hydrophilic end (high regioselectivity) owing to the unique micelle environment in supercritical carbon dioxide that guide a head-on attack of the molecule.

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A new approach of employing metal particles in micelles for the hydrogenation of organic molecules in the presence of fluorinated surfactant and water in supercritical carbon dioxide has very recently been introduced. This is allegedly to deliver many advantages for carrying out catalysis including the use of supercritical carbon dioxide (scCO(2)) as a greener solvent. Following this preliminary account, the present work aims to provide direct visual evidence on the formation of metal microemulsions and to investigate whether metal located in the soft micellar assemblies could affect reaction selectivity. Synthesis of Pd nanoparticles in perfluorohydrocarboxylate anionic micelles in scCO(2) is therefore carried out in a stainless steel batch reactor at 40 degreesC and in a 150 bar CO2/H-2 mixture. Homogeneous dispersion of the microemulsion containing Pd nanoparticles in scCO(2) is observed through a sapphire window reactor at W-0 ratios (molar water-to-surfactant ratios) ranging from 2 to 30. It is also evidenced that the use of micelle assemblies as new metal catalyst nanocarriers could indeed exert a great influence on product selectivity. The hydrogenation of a citral molecule that contains three reducible groups (aldehyde, double bonds at the 2,3-position and the 6,7-position) is studied. An unusually high selectivity toward citronellal (a high regioselectivity toward the reduction of the 2,3-unsaturation) is observed in supercritical carbon dioxide. On the other hand, when the catalysis is carried out in the conventional liquid or vapor phase over the same reaction time, total hydrogenation of the two double bonds is achieved. It is thought that the high kinetic reluctance for double bond hydrogenation of the citral molecule at the hydrophobic end (the 6,7-position) is due to the unique micelle environment that is in close proximity to the metal surface in supercritical carbon dioxide that guides a head-on attack of the molecule toward the core metal particle.

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This paper uses the H1 tracking ideas in the missile guidance problem. The controller performs as a Precision guidance controller for small desired attack angles although theoretically the formulas are valid (when intercepting a maneuvering target in a precision guidance point of view) only for the case of head on collision. The controller essentially navigates the missile in a unique relative arc that is de ned by the missile and target location and the desired attack angle.

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Background: The functional results associated with nonoperative treatment of severely impacted valgus fractures of the proximal part of the humerus are poor, and these injuries are difficult to treat with minimally invasive percutaneous fixation techniques. The aim of this study was to review the functional and radiographic results and complications of a new operative technique in a series of twenty-five patients.

Methods: Over a two-year period, we treated twenty-nine patients with a severely impacted valgus fracture of the proximal part of the humerus. Three patients were lost to follow-up and one died, leaving twenty-five patients who were available for the study. In all of the fractures, the head-shaft angle had been tilted into =160° of valgus and the greater tuberosity was displaced by >1 cm. All patients were treated with open reduction of the fracture, and the space created behind the humeral head was filled with Norian Skeletal Repair System (SRS) bone substitute. The fractures were stabilized with either screws or buttress plate fixation. Associated rotator cuff tears were repaired. All patients underwent functional outcome assessment with use of the Constant, DASH (Disabilities of the Arm, Shoulder and Hand), and SF-36 (Short Form-36) scores at one year, and twelve patients were followed for two years.

Results: All fractures united within the first year, all reductions were maintained, and no patient had signs of osteonecrosis of the humeral head on the latest follow-up radiographs. At one year, the median Constant score was 80 points and the median DASH score was 22 points. The functional results continued to be satisfactory in the twelve patients who were followed for two years. The results in our series were better than those achieved in studies of nonoperative treatment of similar fracture configurations. There were six clinically relevant complications, although none required a reoperation and all six patients had a satisfactory short-term functional outcome.

Conclusions: Internal fixation of severely impacted valgus fractures of the proximal part of the humerus, supplemented by Norian SRS bone substitute to fill the proximal humeral metaphyseal defect, produces good early functional and radiographic outcomes. Additional follow-up will be required to assess whether these initially satisfactory outcomes are maintained over the longer term.

Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

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Background: The functional results associated with nonoperative treatment of severely impacted valgus fractures of the proximal part of the humerus are poor, and these injuries are difficult to treat with minimally invasive percutaneous fixation techniques. The aim of this study was to review the functional and radiographic results and complications of a new operative technique in a series of twenty-five patients.

Methods: Over a two-year period, we treated twenty-nine patients with a severely impacted valgus fracture of the proximal part of the humerus. Three patients were lost to follow-up and one died, leaving twenty-five patients who were available for the study. In all of the fractures, the head-shaft angle had been tilted into > or = 160 degrees of valgus and the greater tuberosity was displaced by >1 cm. All patients were treated with open reduction of the fracture, and the space created behind the humeral head was filled with Norian Skeletal Repair System (SRS) bone substitute. The fractures were stabilized with either screws or buttress plate fixation. Associated rotator cuff tears were repaired. All patients underwent functional outcome assessment with use of the Constant, DASH (Disabilities of the Arm, Shoulder and Hand), and SF-36 (Short Form-36) scores at one year, and twelve patients were followed for two years.

Results: All fractures united within the first year, all reductions were maintained, and no patient had signs of osteonecrosis of the humeral head on the latest follow-up radiographs. At one year, the median Constant score was 80 points and the median DASH score was 22 points. The functional results continued to be satisfactory in the twelve patients who were followed for two years. The results in our series were better than those achieved in studies of nonoperative treatment of similar fracture configurations. There were six clinically relevant complications, although none required a reoperation and all six patients had a satisfactory short-term functional outcome.

Conclusions: Internal fixation of severely impacted valgus fractures of the proximal part of the humerus, supplemented by Norian SRS bone substitute to fill the proximal humeral metaphyseal defect, produces good early functional and radiographic outcomes. Additional follow-up will be required to assess whether these initially satisfactory outcomes are maintained over the longer term.

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Solo Exhibition, Framed Photograhs and Video installations as part of the 'Head On Photography Festival'

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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

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Uma população de Porophyllum ruderale (Jacq.) Cass. ocorrente nos arredores de São José do Rio Preto (SP) foi estudada quanto à estatura, biomassa epígea seca, número de ramos, de capítulos por ramo e por indivíduo e quanto à produção de aquênios por capítulo e por indivíduo. Esta última foi relativamente baixa (média de 2510 aquênios) correspondendo, na base de 80% de germinabilidade, à média de 2008 disseminulos viáveis por indivíduo. Esta capacidade reprodutiva é muito superior ao número de indivíduos que habitualmente ocorrem em condições naturais. A fraca densidade populacional característica da espécie deve ser atribuída, portanto, a outros fatores, tais como, possivelmente, as condições do solo, a competição interespecífica e, talvez, a ação de inimigos naturais. A produção individual de capítulos e de aquênios revelou correlação com a estatura e a biomassa mas o número de aquênios por capítulo (53 em média) não revelou correlação com a estatura, a biomassa e a produção individual de capítulos e de aquénios, demonstrando ser um carater pouco afetado pelo vigor vegetativo.

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The objectives of the present study were to evaluate factors associated with estrous synchronization responses and pregnancy per insemination (P/AI) in Bos indicus beef cows submitted to progesterone-based fixed-time artificial insemination (FTAI) protocols. A total of 2388 cows (1869 Nellore and 519 crossbred Nellore x Angus) from 10 commercial farms were evaluated to determine the relationships among breed, body condition score (BCS) on the first day of the FTAI protocol, the occurrence of estrus between progesterone device removal and FTAI and diameter of largest ovarian follicle (LF) at FTAI on estrous synchronization responses and P/AI. Cows (n=412 primiparous; 1976 multiparous) received an intravaginal device containing progesterone or an ear implant containing norgestomet (a progestin), and an injection of estradiol at the beginning of the estrous synchronization protocol. Body condition was scored using a 1-5 scale on the first day of the FTAI protocol and at 30-60 days postpartum. Females received 300IU of equine chorionic gonadotropin (eCG) and PGF(2 alpha) on the day the progesterone device/implant was removed and were inseminated 48-60h later. At insemination, cows (n=2388) were submitted to an ultrasonographic exam to determine the diameter of the LF. Follicles were classified into four categories based on mean and standard deviation (SD) of the LF (LF1 = two SD below the mean; LF2 = mean minus one SD; LF3 = mean plus one SD; LF4 = two SD above the mean). Ovulation rate was determined in a subset of cows (n=813) by three consecutive ultrasonographic exams: (1) at time of progesterone device/implant removal, (2) at time of FTAI and (3) 48 h after FTAI. Ovulation was defined as the disappearance of a large follicle (>= 8.0 mm) that was previously recorded. Estrus was determined in a subset of the cows (n = 445) by the activation of a detection of estrous patch placed on the tail head on the day of progesterone device/implant removal. Pregnancy was diagnosed 30 days after FTAI. Pregnancy was influenced (P = 0.001) by follicle diameter [LF1 = 27.5% (81/295), LF2 = 46.6% (328/705), LF3 = 57.9% (647/1118), LF4 = 63.3% (171/270)] and the occurrence of estrus [estrus = 67.7% (174/257) and no estrus = 36.2% (68/188)]. Follicle diameter at FTAI influenced ovulation rate [LF1 = 42.5% (34/80), LF2 = 73.9% (161/218), LF3 = 95.8% (407/425), LF4 = 97.8% (88/90)], the occurrence of estrus [LF1 = 54.8% (51/93), LF2 = 33.6% (43/128), LF3 = 68.9% (126/183), LF4 = 90.2% (37/41)] and P/AI among cows that had ovulations [LF1 =32.4% (11/34), LF2 = 50.3% (81/161), LF3 = 60.0% (244/407), LF4 = 68.2% (60/88)]. Improving estrous responses between progesterone device withdrawal and FTAI and increasing the diameter of the LF at FTAI may be important aspects to achieve improved estrous synchronization responses and P/AI following progesterone/progestin and estradiol based FTAI protocols in suckled Bos indicus cows. (C) 2010 Elsevier B.V. All rights reserved.

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Four perylene derivatives (PTCD) have been used as transducing materials in taste sensors fabricated with nanostructured Langmuir-Blodgett (LB) films deposited onto interdigitated gold electrodes. The Langmuir monolayers of PTCDs display considerable collapse pressures, with areas per molecule indicative of an edge-on or head-on arrangement for the molecules at the air/water interface. The sensing units for the electronic tongue were produced from 5-layer LB films of the four PTCDs, whose electrical response was characterized with impedance spectroscopy. The distinct responses of the PTCDs, attributed to differences in their molecular structures, allowed one to obtain a finger printing system that was able to distinguish tastes (salty, sweet, bitter and sour) at 1 μM concentrations, which, in some cases, are three orders of magnitude below the human threshold. Using Principal Component Analysis (PCA) data analysis, the electronic tongue also detected trace amounts of a pesticide and could distinguish among samples of ultrapure, distilled and tap water, and two brands of mineral water. © 2004 by American Scientific Publishers. All rights reserved.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)