189 resultados para Poison


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Tetrahexahedral Pt nanocrystals (THH Pt NCs), bound by high index facets, belong to an emerging class of nanomaterials that promise to bridge the gap between model and practical electrocatalysts. The atomically stepped surfaces of THH Pt NCs are extremely active for the electrooxidation of small organic molecules but they also readily accommodate the dissociative chemisorption of such species, resulting in poisoning by strongly adsorbed CO. Formic acid oxidation is an ideal reaction for studying the balance between these competing catalyst characteristics, since it can proceed by either a direct or a CO mediated pathway. Herein, we describe electrochemical and in situ FTIR spectroscopic investigations of formic acid electrooxidation at both clean and Au adatom modified THH Pt NC surfaces. The Au decoration leads to higher catalytic currents and enhanced CO2 production in the low potential range. As the CO oxidation behaviour of the catalyst is not changed by the presence of the Au, it is likely that the role of the Au is to promote the direct pathway. Beyond their fundamental importance, these results are significant in the development of stable, poison resistant anodic electrocatalysts for direct formic acid fuel cells.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Electrochemically modified ethylene oxidation over a PI film supported on the Na+ ion conductor beta '' alumina has been studied over a range of conditions encompassing both promotion and poisoning, The system exhibits reversible behavior, and the data are interpreted in terms of (i) Na-enhanced oxygen chemisorption and (ii) poisoning of the surface by accumulation of Na compounds. At low Na coverages the first effect results in increased competitive adsorption of oxygen at the expense of ethylene, resulting in an increased rate, At very negative catalyst potentials (high Na coverage) both effects operate to poison the system: the increased strength of the Pt-O bond and coverage of the catalytic surface by compounds of Na strongly suppress the rate, Kinetic and spectroscopic results for ethylene oxidation over a Pt(111)-Na model catalyst shed light on important aspects of the electrochemically controlled system, Low levels of Na promote the reaction and high levels poison it, mirroring the behavior observed under electrochemical control and strongly suggesting that sodium pumped from the solid electrolyte is the key species, XP and Auger spectra show that under reaction conditions, the sodium exists as a surface carbonate. Post-reaction TPD spectra and the use of (CO)-C-13 demonstrate that CO is formed as a stable reaction intermediate, The observed activation energy (56 +/- 3 kJ/mol) is similar to that measured for CO oxidation under comparable conditions, suggesting that the rate limiting step is CO oxidation. (C) 1996 Academic Press, Inc.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

On 25 April 1998 part of the tailings pond dike of the Aznalcollar Zn mine north of the Guadalquivir marshes (Donana) in southern Spain collapsed releasing an estimated 5 million m3 of acidic metal-rich waste. This event contaminated farmland and wetland up to >40 km downstream, including the 900-ha 'Entremuros', an important area for birds within the Donana world heritage site. In spite of the contamination, birds continued to feed in this area. Samples of two abundant macrophytes (Typha dominguensis and Scirpus maritimus) were taken from the Entremuros and nearby uncontaminated areas; these plants are important food items for several bird species. Analyses showed that in the Entremuros mean plant tissue concentrations of Cd were 3-40-fold (0.8-7.4 ppm) and Zn 20-100-fold (20-3384 ppm) greater than those from control areas. Comparable dietary concentrations of Zn have been reported to cause severe physiological damage to aquatic birds under experimental conditions. Elevated Cd concentrations are of concern as Cd bioconcentrates and is a cumulative poison. Metals released in this accident are moving into this food-chain and present a considerable risk to species feeding on Typha sp. and Scirpus sp. Many other food-webs exist in this area and require detailed examination to identify the species at risk, and to facilitate the management of these risks to minimise future impacts to the wildlife of Donana. Copyright (C) 1999 Elsevier Science Ltd.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Contient : 1 « Le riche don d'amoureuse mercy ». « Me NICOLE OSMONT » ; 2 « En vray amour il n'est riens impossible ». « Me JAQUES LE LYEUR » ; 3 « L'arbre de vie en l'isle fortunée ». « Me JEHAN ALYNE » ; 4 « Le sainct desert plain de manne angelique ». « Damp NICOLE LESCARRE » ; 5 « Le grant decret d'auctorité divine ». « Me JAQUES FILLASTRE » ; 6 « Le restaurant qui pour mort rend la vie ». « COURNILLE, alias TOURMENTE » ; 7 « Romme où se tient le sainct pape Innocent ». « Damp NICOLE LESCARRE » ; 8 « Le bien de paix aux humains necessaire ». « Me NICOLE DU PUYS » ; 9 « Dessus la loy d'humaine congnoissance ». « Me YSAMBERT BUSQUET » ; 10 « Femme parfaicte en nature imparfaicte ». « Me GUILLAUME THIBAULD » ; 11 « La souveraine en parfaicte beaulté ». « PIERRE CRIGNON » ; 12 « Ung corps parfaict sus ordre elementaire ». « Me JAQUES LE LYEUR » ; 13 « Au fondz d'yver printemps qui rend verdure ». « Me INNOCENT TOURMENTE » ; 14 « La purité du feu elementaire ». « Me P. AVRIL » ; 15 « La digne couche où le roy reposa ». « Me CLEMENT MAROT » ; 16 « Harnoys d'espreuve au puissant roy de gloire ». « PIERRES CRIGNON » ; 17 « Le regne franc de la loy tributaire ». « Me GUILLAUME THIBAULD » ; 18 « Saine et entiere en note et escripture ». « Me CHARLES DE SAINCT GERMAIN » ; 19 « Femme en la loy et hors la loy conceue ». « Me JO. DE BEAUVOYS » ; 20 « Selon ton nom louenge te soit faicte ». « Le general DE CAEN » ; 21 « Au grant festin du cereal convive ». « Me THOMAS LE PREVOST » ; 22 « La saincte Bible où verité repose ». « Me GUILLAUME THYBAULD » ; 23 « Pour le tout beau conceue toute belle ». « Me JEHAN DE BEAUVOYS » ; 24 « Fille obtenant la grace de son pere ». « Me ADAM LAIR » ; 25 « Le noble cueur commencement de vie ». « Me JAQUES LE LYEUR » ; 26 « Triumphanment la victoire obtenue ». « GUILLAUME DE SEVYNGUEHEN » ; 27 « Le feu d'amour pour reschauffer le monde ». « Me NICOLE DU PUYS » ; 28 « Du faulx serpent la puissance a destruicte ». « Me JAQUES LE LIEUR » ; 29 « Vray Mythridat contre mordz de vipere ». « Me INNOCENT TOURMENTE » ; 1 « Toute belle en ame et corps nect ». « Me JAQUES LE LYEUR » ; 2 « La bouge plaine de salutz ». « DUPUYS » ; 3 « La main armée aux ennemys ». « Damp NICOLE LESCARRE » ; 4 « La terre rendent bled de grace ». « Me GUILLAUME THIBAULT » ; 5 « Le nombre d'or de l'an de grace ». « Me THOMAS LEPREVOST » ; 6 « Victoire sur mes ennemys ». « Me JAQUES LELYEUR » ; 7 « Pour les siens poison importable ». « Me REUIL DOUBLET » ; 8 « Entre deux vertes une meure ». « Me THOMAS LEPREVOST » ; 9 « Entre deux vertes une meure ». « Damp NICOLE LESCARRE » ; 10 « Entre imparfaictz toute parfaicte ». « Me GUILLAUME DE SEVYNGUEHEN » ; 11 « Il n'est à Dieu rien impossible ». « Me GUILLAUME THYBAULT » ; 12 « Toutes à l'oeil, mais une au cueur ». « Me THOMAS LEPREVOST » ; 13 « Grace en toy par divin plaisir ». « Damp NICOLLE LESCARRE » ; 14 « Conception plaine de grace » ; 15 « Juste balence et loyal poix ». « Damp NICOLE LESCARRE » ; 16 « La haulte tour de fortitude ». « LESCARRE » ; 17 « La franche terre du grand roy ». « JEHAN PARMENTIER » ; 18 « D'azur à trois fleurs de lys d'or ». « PIERRE CRIGNON » ; 19 « Pour humains lyez deslier ». « Me JAQUES LE LIEUR » ; 20 « Corde l'homme et Dieu accordant ». « LIEUR » ; 21 « Ne craignez plus, la beste est prise ». « Me JAQUES LE LIEUR » ; 1 « Seule sans cy ». « Me JAQUES LE LIEUR » ; 2 « Par devolut ». « Me PIERRES AVRIL » ; 3 « Le povre Adam ». « Me NICOLE DU PUYS » ; 4 « Fors vous ». « Me NICOLE OSMONT » ; 5 « En fleur et fruict ». « Me JEHAN ALYNE » ; 6 « En unité ». « Me PIERRES AVRIL » ; 7 « Comme nature ». « Me CLEMENT MAROT » ; 8 « Grace sur grace » « Me THOMAS LEPREVOST » ; 9 « En mon concept ». « Me INNOCENT TOURMENTE » ; 10 « Ou bien de Dieu ». « GUILLAUME DE SEVYNGUEHEN » ; 11 « Une et non plus ». « Me THOMAS LEPREVOST » ; 12 « En tout honneur ». « Me PIERRES AVRIL » ; 13 « Pour moy sans plus ». « Me GUILLAUME TYBAULD » ; 14 « Grace nous vient ». « Damp NICOLE LESCARRE » ; 15 « Par mon cher filz ». « Me GUILLAUME THIBAULD » ; 16 « Mauldict serpent ». « AVRIL » ; 17 « Voulez vous myeulx ». « Me JEHAN BROYSE » ; 18 « Nonobstant loy ». « G. DE SEVYNGUEHEN » ; 19 « Au gré d'amour ». « Me GUILLAUME TYBAULD » ; 20 « Est ce bien faict ». « L'abbé DE SAINCT VANDRILLE » ; 21 « Hors paradis ». « Me JAQUES LE LYEUR » ; 1 « Deploracion de l'acteur » ; 2 « Espitre », par « LE LIEUR »

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this study, I build upon my previous research in which I focus on religious doctrine as a gendered disciplinary apparatus, and examine the witch trials in early modem England and Italy in light of socio-economic issues relating to gender and class. This project examines the witch hunts/trials and early modem visual representations of witches, and what I suggest is an attempt to create docile bodies out of members of society who are deemed unruly, problematic and otherwise 'undesirable'; it is the witch's body that is deemed counternormative. This study demonstrates that it is neighbours and other acquaintances of accused witches that take on the role of the invisible guard of Bantham's Panoptic on. As someone who is trained in the study of English literature and literary theory, my approach is one that is informed by this methodology. It is my specialization in early modem British literature that first exposed me to witch-hunting manuals and tales of the supernatural, and it is for this reason that my research commences with a study of representations of witches and witchcraft in early modem England. From my initial exposure to such materials I proceed to examine the similarities and the differences of the cultural significance of the supernatural vis-a.-vis women's activities in early modem Italy. The subsequent discussion of visual representations of witches involves a predominance of Germanic artists, as the seminal work on the discernment of witches and the application of punishment known as the Malleus Meleficarum, was written in Germany circa 1486. Textual accounts of witch trials such as: "A Pitiless Mother (1616)," "The Wonderful Discovery of the Witchcrafts of Margaret and Philippa Flower (1619)," "Magic and Poison: The Trial ofChiaretta and Fedele (circa 1550)", and the "The Case of Benvegnuda Pincinella: Medicine Woman or Witch (1518),"and witchhunting manuals such as the Malleus Melejicarum and Strix will be put in direct dialogue with visual representations of witches in light of historical discourses pertaining to gender performance and gendered expectations. Issues relating to class will be examined as they pertain to the material conditions of presumed witches. The dominant group in any temporal or geographic location possesses the tools of representation. Therefore, it is not surprising that the physical characteristics, sexual habits and social material conditions that are attributed to suspected witches are attributes that can be deemed deviant by the ruling class. The research will juxtapose the social material conditions of suspected witches with the guilt, anxiety, and projection of fear that the dominant groups experienced in light of the changing economic landscape of the Renaissance. The shift from feudalism to primitive accumulation, and capitalism saw a rise in people living in poverty and therefore an increased dependence upon the good will of others. I will discuss the social material conditions of accused witches as informed by what Robyn Wiegman terms a "minoritizing discourse" (210). People of higher economic standing often blamed their social, medical, and/or economic difficulties on the less fortunate, resulting in accusations of witchcraft.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

La diversification des signaux aposématiques dans un cadre de mimétisme müllérien est un phénomène intrigant. Alors que la théorie relative à l'aposématisme et au mimétisme suggère l'évolution vers un signal aposématique unique, d'impressionnantes variations peuvent être observées entre les populations, et cela à petite échelle spatiale. Il a été supposé que la variation spatiale des pressions de sélection engendrées par différents prédateurs puisse être à l'origine de ce phénomène. Afin de tester cette hypothèse, nous avons étudié la transition entre deux systèmes géographiques caractérisés par des patrons aposématiques distincts chez des grenouilles mimétiques et toxiques du nord du Pérou (Dendrobatidae) en combinant les outils de génétique des populations aux outils écologiques. Dans chacun de ces systèmes, Ranitomeya imitator vit en sympatrie avec R. ventrimaculata ou R. variabilis. Il s'agit du principal exemple empirique suggérant que dans un cadre de mimétisme müllérien, il n'y a pas convergence des signaux aposématiques des deux espèces, mais plutôt convergence unidirectionnelle où R. imitator, étant polymorphe, imite des espèces monomorphes avec lesquelles elle est sympatrique. Premièrement, les résultats réfutent les prémisses qui suggèrent que R. imitator converge vers le signal aposématique d’une autre espèce. La haute similarité génétique entre les espèces modèles suggère qu'elles ont divergé plus récemment que les populations de R. imitator ou qu'elles sont encore connectées par du flux génique. Ces résultats indiquent que ces espèces ont été identifiées à tort comme des espèces différentes. De fait, l'identification de l'espèce imitatrice basée sur la variabilité phénotypique est invalidée dans ce système puisque R. imitator et R. variabilis/ventrimaculata démontrent la même variabilité. Deuxièmement, nos résultats démontrent que la prédation varie spatialement, autant en intensité qu'en direction, créant ainsi un paysage hétérogène de pressions de sélection. Ainsi, de fortes pressions de prédation stabilisatrice permettent le maintien de l'organisation géographique de différents signaux aposématiques et expliquent l'uniformité de ces signaux ainsi que les relations mimétiques. Par contre, le relâchement temporaire des pressions de prédation permet l'apparition de nouveaux phénotypes aposématiques via les processus évolutifs neutres, conduisant à un haut polymorphisme au niveau de ces populations. L'interaction de ces modes sélectifs nous a permis de démontrer pour la première fois comment la théorie évolutive de Wright (shifting balance theory) permet la diversification adaptative dans un système naturel. Pour conclure, cette étude a permis de mettre en évidence à quel point les systèmes de mimétisme müllérien peuvent être dynamiques. L'alternance spatiale entre les processus évolutifs neutres et la sélection naturelle permet l'émergence de nouveaux phénotypes aposématiques à une échelle locale, ainsi que l'apparition d'une organisation géographique des signaux d'avertissement et des relations de mimétisme müllérien.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Cette étude examine comment différents textes du XVIIIe siècle traitent du roman. L’hypothèse est la suivante : le genre choisi pour parler du roman participe de manière intrinsèque à la critique ou à l’apologie véhiculée dans l’œuvre. Le corpus est composé de quatre textes plus ou moins (re)connus par les historiens de la littérature narrative : De l’Usage des romans (1734) de Lenglet-Dufresnoy, le Voyage merveilleux du Prince Fan-Férédin dans la Romancie (1735) du père Bougeant, De Libris qui vulgò dicuntur Romanenses (1736) du père Porée et les Entretiens sur les romans (1755) du père Jacquin. À l’aide d’une méthode hybride d’analyse générique et d’analyse rhétorique du discours, cette étude s’intéresse aux genres employés par les auteurs du corpus (le traité, le roman, le discours académique et l’entretien) de même qu’à trois thématiques argumentatives reliées au roman (le poison, l’amour et la femme).

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This thesis is devoted to the study of some stochastic models in inventories. An inventory system is a facility at which items of materials are stocked. In order to promote smooth and efficient running of business, and to provide adequate service to the customers, an inventory materials is essential for any enterprise. When uncertainty is present, inventories are used as a protection against risk of stock out. It is advantageous to procure the item before it is needed at a lower marginal cost. Again, by bulk purchasing, the advantage of price discounts can be availed. All these contribute to the formation of inventory. Maintaining inventories is a major expenditure for any organization. For each inventory, the fundamental question is how much new stock should be ordered and when should the orders are replaced. In the present study, considered several models for single and two commodity stochastic inventory problems. The thesis discusses two models. In the first model, examined the case in which the time elapsed between two consecutive demand points are independent and identically distributed with common distribution function F(.) with mean  (assumed finite) and in which demand magnitude depends only on the time elapsed since the previous demand epoch. The time between disasters has an exponential distribution with parameter . In Model II, the inter arrival time of disasters have general distribution (F.) with mean  ( ) and the quantity destructed depends on the time elapsed between disasters. Demands form compound poison processes with inter arrival times of demands having mean 1/. It deals with linearly correlated bulk demand two Commodity inventory problem, where each arrival demands a random number of items of each commodity C1 and C2, the maximum quantity demanded being a (< S1) and b(

Relevância:

10.00% 10.00%

Publicador:

Resumo:

David Arnold who retired this year as the Professor of Asian and Global History at the University of Warwick remains one of the most prolific historians of colonial medicine and modern South Asia. A founding member of the subaltern studies collective, he is considered widely as a pioneer in the histories of colonial medicine, environment, penology, hunger and famines within South Asian studies and beyond. In this interview he recalls his formative inspirations, ideological motivations and reflects critically on his earlier works, explaining various shifts as well as map- ping the possible course of future work. He talks at length about his forthcoming works on everyday technology, food and monsoon Asia. Finally, he shares with us his desire of initiating work on an ambitious project about the twin themes of poison and poverty in South Asian his- tory, beginning with the Bengal famine in the late eighteenth century and ending with the Bhopal gas tragedy of the early 1980s. This conversation provides insights into the ways in which the field of medical history in modern South Asia has been shaped over the past three decades through interactions with broader discussions on agency, resistance, power, everydayness, subal- tern studies, global and spatial histories. It hints further at the newer directions which are being opened up by such persisting intellectual entanglements.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Given the growing environmental crisis caused by degradation, mainly due to the use of polluting energy sources, increasing the growing use of renewable energies worldwide, with emphasis on solar energy, an abundant supply and available to everyone, which can be harnessed in several ways: electricity generation; dehydration of food; heating, disinfection and distillation and cooking. The latter has as its primary feature the viability of clean, renewable energy for society, combating ecological damage caused by large-scale use of firewood for cooking foods, use in tropical countries with high solar radiation, and has funding NGOs throughout the world with the goal of achieving low-income population. The proposed project consists of a solar cooker for concentration, working from the reflection of sunlight by a hub that they converge to a focal point at the bottom of the pot, getting lots of heat. The solar cooker under study consists of two elliptical reflecting parabolas made from the recycling of scrap TV antenna, having 0.29 m² of surface area for each antenna, which were covered by multiple mirrors of 2 mm thick and mounted on a metal structure, with correction for the mobility of the apparent movement of the sun. This structure was built with the recycling of scrap metal, possessing a relatively low cost compared with other solar cookers, around US$ 50.00. This cost becomes negligible, since that will involve a great benefit to not have fuel costs for each meal, unlike the use of gas or firewood for cooking food. The tests show that the cooker has reached the maximum temperature of 740 ° C, for boiling water in an average time of 28 minutes, cooking various types of foods such as potatoes, rice and pasta in an average time of 45 minutes and still going as a solar oven, making pizza baking and meat. These cooking times do not differ much from the cooking times on a gas stove, it becomes the solar cooker as a good consumer acceptance, and furthermore not to deliver the same gases that can poison the food as with the wood stove. Proves the viability of using the stove to cook or bake in two daily meals for a family, still presenting a position to improve his performance with the addition of new materials, equipment and techniques

Relevância:

10.00% 10.00%

Publicador:

Resumo:

As serpentes peçonhentas dos gêneros Bothrops e Crotalus têm sido mantidas em cativeiro visando à extração de venenos para a produção de imunobiológicos. O conhecimento da fisiologia desses animais e as alterações na concentração de proteínas e suas frações séricas são importantes para a identificação precoce de importantes enfermidades que cursam com estados de hipoproteinemia e hiperproteinemia. O objetivo do trabalho foi determinar a concentração de proteína total e o perfil eletroforético das proteínas séricas de serpentes Crotalus durissus terrificus (cascavel) criadas em cativeiro. Foram colhidas amostras de sangue da veia coccígea ventral de 21 serpentes adultas e sadias, divididas em dois grupos: Grupo 1 de 12 machos com peso médio de 588,89±193,55g, e Grupo 2 de nove fêmeas com peso médio de 708,33±194,04g. A proteína total sérica foi determinada pelo método de refratometria e a eletroforese em gel de agarose. Obtiveram-se valores da proteína total sérica (g/dL) de 4,51±0,50 para machos e de 4,82±0,72 para fêmeas, e para machos e fêmeas de 4,64±0,61. Foram identificadas pela eletroforese quatro frações protéicas (g/dL): albumina, a, b, g-globulinas e calculada a relação albumina:globulina. As serpentes fêmeas apresentaram maiores valores para as variáveis, albumina e para a relação albumina/globulina (AG) diferindo significativamente (P<0,05) do grupo de machos, porém sem significado clínico.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Crotalic envenomation represents the highest number of deaths when compared to other snakebite envenomations of medical interest. Crotalic venom has important characteristics such as neurotoxicity, myotoxicity, nephrotoxicity, and clotting and hemolytic action. We evaluated the clinical and laboratory aspects of Crotalus durissus terrificus experimental envenomation in Wistar rats treated with antivenom and the aqueous extract of the plant mikania glomerata. The animals were divided into three groups: Group C (control); Group VS-venom and antivenom; Group VSM-venom, antivenom and aqueous extract of M glomerata. Crotalic poison caused clinical and laboratory alterations in Wistar mice. Significant clinical alterations were: temperature decrease, edema in the venom inoculated member, sedation and a locomotion decrease in groups VS and VSM when compared with group C. A faster recovery from sedation was observed only for animals of group VSM when compared to VS. There was an increase in the number of leukocytes, neutrophils and creatine kinase in the VS and VSM groups, compared to group C. Wistar rats showed a high resistance to crotalic venom. Additional studies with different doses, time of treatment, different administration methods and histopathological and immunological studies are necessary to understand the action of M glomerata in crotalic accidents. Rev. Biol. Trop. 57 (4): 929-937. Epub 2009 December 01.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Anexas ao aparelho do ferrão dos himenópteros aculeados encontram-se as glândulas de veneno e as de Dufour. A glândula de veneno é originada das glândulas associadas ao ovopositor dos himenópteros ancestrais não aculeados, já a glândula de Dufour é menos derivada, homóloga das glândulas colateriais dos outros insetos, sendo encontrada em todas as fêmeas dos himenópteros. Nestes insetos sua função é, em grande parte, desconhecida, mas, em formigas, parece estar envolvida com a comunicação e a defesa e, nas abelhas não sociais, com a construção e a proteção do ninho. Nas vespas pode estar relacionada ao reconhecimento parental. Foram observadas diferenças morfológicas e na composição química da secreção da glândula de Dufour entre as espécies, bem como na mesma espécie, entre as castas dos himenópteros sociais e entre indivíduos da mesma casta desempenhando diferentes funções ou pertencentes a ninhos diferentes. Portanto, nos himenópteros, sua função original de produzir substâncias para proteger os ovos ou favorecer a ovoposição parece ter sido substituída ou complementada com a função de produzir semioquímicos com função na comunicação.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)