917 resultados para Caribbean Literature. North American Literature. Immigration. ImmigrantWriting. Julia Alvarez


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A escala Hassles & Uplifts avalia a intensidade da resposta a pequenos eventos cotidianos, sendo considerada um preditor de sintomas psicológicos. O objetivo deste estudo foi avaliar uma tradução da escala Hassles & Uplifts, aqui intitulada Aborrecimentos e Alegrias; para tal, realizou-se a réplica de um estudo norte-americano que mediu o desempenho, nessa escala, de indivíduos cujo padrão de comportamento fosse do tipo A ou B segundo a escala de Jenkins (Escala Aborrecimentos e Alegrias). As escalas Aborrecimentos e Alegrias e A/B foram aplicadas em 145 universitários brasileiros. Os resultados mostraram que: 1) as pontuações médias de Aborrecimentos e Alegrias foram similares às do estudo norte-americano, exceto pelos Aborrecimentos dos participantes tipo B; 2) a intensidade das Alegrias dos participantes tipo A foi significativamente superior à dos tipo B, como na literatura; 3) a intensidade de Alegrias e Aborrecimentos não diferiu entre os dois tipos, provavelmente devido à especificidade da época do teste. Concluiu-se que o padrão e a consistência dos resultados indicam que a tradução pode ser utilizada como instrumento confiável de pesquisa.

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We studied the similarities and differences between Brazilian Spiritistic mediums and North American dissociative identity disorder (DID) patients. Twenty-four mediums selected among different Spiritistic organizations in Sao Paulo, Brazil, were interviewed using the Dissociative Disorder Interview Schedule, and their responses were compared with those of DID patients described in the literature. The results from Spiritistic mediums were similar to published data on DID patients only with respect to female prevalence and high frequency of Schneiderian first-rank symptoms. As compared with individuals with DID, the mediums differed in having better social adjustment, lower prevalence of mental disorders, lower use of mental health services, no use of antipsychotics, and lower prevalence of histories of physical or sexual childhood abuse, sleepwalking, secondary features of DID, and symptoms of borderline personality. Thus, mediumship differed from DID in having better mental health and social adjustment, and a different clinical profile.

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Chagas` disease (CD) is highly prevalent in South America. Brazilian surgeons and gastroenterologists gained valuable experience in the treatment of CD esophagopathy (chagasic achalasia) due to the high number of cases treated. The authors reviewed the lessons learned with the treatment of achalasia by different centers experienced in the treatment of Chagas` disease. Preoperative evaluation, endoscopic treatment (forceful dilatation and botulinum toxin injection), Heller`s myotomy, esophagectomy, conservative techniques other than myotomy, and reoperations are discussed in the light of personal experiences and review of International and Brazilian literature. Aspects not frequently adopted by North American and European surgeons are emphasized. The review shows that nonadvanced achalasia is frequently treated by Heller`s myotomy. Endoscopic treatment is reserved to limited cases. Treatment for end-stage achalasia is not unanimous. Esophagectomy was a popular treatment in advanced disease; however, the morbidity/mortality associated to the procedure made some authors seek different alternatives, such as Heller`s myotomy and cardioplasties. Minimally invasive approach to esophageal resection may change this concept, although few centers perform the procedure routinely.

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Este artigo ?? uma resenha da literatura sobre o Executivo que discute o impacto dos sistemas parlamentarista e presidencialista na capacidade governamental de formular e implementar pol??ticas p??blicas. Ao longo do texto, busca-se identificar fatores que permitem ou bloqueiam o exerc??cio de uma fun????o coordenadora e unificadora de a????es, analisando a rela????o entre os poderes Executivo e Legislativo, a estrutura do poder Executivo e as rela????es entre o Executivo pol??tico e a burocracia. Os estudos sobre parlamentarismo enfocam: import??ncia dos partidos, papel dos ministros, extens??o do poder do primeiro ministro e papel coletivo do gabinete. J?? os trabalhos sobre presidencialismo v??o de pesquisas sobre o Congresso norte-americano, envolvendo infer??ncias estat??sticas e an??lises baseadas na teoria institucional a estudos de caso sobre a American Politics (presid??ncia e lideran??a). Apesar das diferen??as entre parlamentarismo e presidencialismo, a literatura indica que mecanismos institucionais de controle de agenda produzem os mesmos efeitos nos dois sistemas.

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INTRODUCTION: Among psychiatric disorders schizophrenia is often said to be the condition with the most disputed definition.The Bleulerian and Schneiderian approaches have given rise to diagnostic formulations that have varied with time and place. Controversies over the concept of schizophrenia were examined within European/North American settings in the early 1970s but little has since been reported on the views of psychiatrists in developing countries. In Brazil both concepts are referred to in the literature. A scale was developed to measure adherence to Bleulerian and Schneiderian concepts among psychiatrists working in S. Paulo. METHODOLOGY: A self-reported questionnaire comprising seventeen visual analogue-scale statements related to Bleulerian and Schneiderian definitions of Shizophrenia, plus sociodemographic and training characteristics, was distributed to a non-randomised sample of 150 psychiatrists. The two sub-scales were assessed by psychometric methods for internal consistency, sub-scale structure and test-retest reliability. Items selected according to internal consistency were examined by a two-factor model exploratory factor analysis. Intraclass correlation coefficients described the stability of the scale. RESULTS: Replies were received from 117 psychiatrists (mean age 36 (SD 7.9)), 74% of whom were made and 26% female. The Schneiderian scale showed better overall internal consistency than the Bleulerian scale. Intra-class correlation coefficients for test-retest comparisons were between 0.5 and 0.7 for Schneiderian items and 0.2 and 0.7 for Bleulerian items. There was no negative association between Bleulerian and Schneiderian scale scores, suggesting that respondents may hold both concepts. Place of training was significantly associated with the respondent's opinion; disagreement with a Bleulerian standpoint predominated for those trained at the University of S. Paulo. CONCLUSIONS: The less satisfactory reliability for the Bleulerian sub-scale limits confidence in the whole scale but on the other hand this questionnaire contributes to the understanding of the controversy over Bleulerian and Schneiderian models for conceptualisation of schizophrenia, the former requiring more inference and therefore being prone to unreliability.

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The objective of this paper is to review and discuss the literature about volunteers’ motivations to donate their time to NGOs (Non Governmental Organisations). According to Parboteeah, Cullenb & Lim (2004) management research has not paid much attention to voluntarism, however, voluntarism is a substantial part of productive work for many societies. Wilson & Pimm (1996) show that in Great Britain about 39% of the adult population has been involved in some volunteer activity for some period of time. In the U.S.A. these values reach 50% (Wilson & Pimm, 1996). Considering the benefits that voluntarism can bring to an organisation, we understand that more attention must be devoted to this phenomenon. The more an organisation knows volunteers, the better this organisation will be able to meet the needs and expectations of these individuals. We present a literature review that illustrates and compares the different motivations associated with volunteer work. The paper includes a bibliographical databases search in specialised journals. The search used the key words “motivations” and “voluntarism” (in the heading and text body) and covered all numbers between 2000 and 2007. We identify the existence of repeated motivations (Holmberg & Söderlung, 2005; Prouteau & Wolff, 2008; Soupourmas & Ironmonger, 2001; Yavas & Riecken, 1997), which allow the establishment of a typology of volunteers’ motivations, based on four categories: altruism, social needs, self-esteem, learning and self-development. Finally we identify three main gaps in the literature that justify further research. First, research focusing on the differences between motivations related to volunteers’ "Attraction" versus "Retention" in NGO’s is nil. Second, the great majority of the studies rely on north American (USA and Canada) and Australian context, which demands for further research in European countries. Third, the majority of NGOs researched are related to sport, art or the environment, and it would be interesting to explore the relationship between motivation and NGO type. These questions may obtain interesting answers for NGO management, in particular with regard to volunteer attraction and retention.

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Este trabalho revê e discute a literatura sobre as motivações dos voluntários para doarem o seu tempo às ONG’s. Quanto melhor uma organização conhecer os voluntários, mais essa organização poderá ir de encontro às necessidades e expectativas desses mesmos indivíduos. Por isso, compreender as motivações que podem levar um indivíduo a doar o seu tempo a uma determinada organização é relevante na gestão das ONG’s. Primeiro, o artigo discute o estado da arte do voluntariado formal e as motivações dos indivíduos voluntários não dirigentes. Apresenta-se uma pesquisa a bases de dados bibliográficas, que inclui revistas especializadas na investigação de voluntariado. Depois, o artigo mostra e compara os diferentes tipos de motivações associadas ao trabalho voluntário e propõe uma tipologia que agrupa as motivações dos voluntários em quatro tipos: altruísmo, pertença, ego e reconhecimento social e aprendizagem e desenvolvimento. Por fim, efectua-se uma análise que indica três lacunas na literatura das motivações dos voluntários que justificam investigação adicional: (i) a omissão de diferenças entre as motivações relacionadas com a “Atracção” versus a “Retenção” dos voluntários; (ii) a focalização das investigações no contexto norte-americano e australiano; e (iii) a ausência de análises comparativas que relacionem as motivações por tipos de ONG’s.

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Dissertação de Mestrado em Ciências Económicas e Empresariais.

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In the history of modern communication, after the development of the printing press, the telegraph unleashed a revolution in communications. Today, Internet is in many ways its heir. Reflections on the telegraph may open up perspectives concerning tendencies, possibilities and pitfalls of the Internet. The telegraph has been well explored in important literature on communication and media which tends to emphasize the history of this technology, its social context and institutional meaning [e.g. Robert L. Thompson, 1947, Tom Standage, 2007 [1998]. James W. Carey, the North- American critical cultural studies' mentor, in his essay "Technology and Ideology. The Case of the Telegraph" (2009 [1983]), suggests a distinctive approach. In the telegraph, Carey sees the prototype of many subsequent commercial empires based on science and technology, a pioneer model for complex business management; an example of interest struggle for the patents control; an inductor of changes both in language and in structures of knowledge; and a promoter of a futurist and utopian thought of information technologies. Having in mind a revolution in communications promoted by the Internet, this paper revisits this seminal essay to explore its great attainment, as well as the problems of this kind of approach which conceives the innovation of the telegraph as a metaphor for all the innovations announcing the modern stage of history and determining still today the major lines of development in modern communication systems.

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1) It may seem rather strange that, in spite of the efforts of a considerable number of scientists, the problem of the origin of indian corn or maize still has remained an open question. There are no fossil remains or archaeological relics except those which are quite identical with types still existing. (Fig. 1). The main difficulty in finding the wild ancestor- which may still exist - results from the fact that it has been somewhat difficult to decide what it should be like and also where to look for it. 2) There is no need to discuss the literature since an excellent review has recently been published by MANGELSDORF and REEVES (1939). It may be sufficient to state that there are basically two hypotheses, that of ST. HILAIRE (1829) who considered Brazilian pod corn as the nearest relative of wild corn still existing, and that of ASCHERSON (1875) who considered Euchlaena from Central America as the wild ancestor of corn. Later hypotheses represent or variants of these two hypotheses or of other concepts, howewer generally with neither disproving their predecessors nor showing why the new hypotheses were better than the older ones. Since nearly all possible combinations of ideas have thus been put forward, it har- dly seems possible to find something theoretically new, while it is essential first to produce new facts. 3) The studies about the origin of maize received a new impulse from MANGELSDORF and REEVES'S experimental work on both Zea-Tripsacum and Zea-Euchlaena hybrids. Independently I started experiments in 1937 with the hope that new results might be obtained when using South American material. Having lost priority in some respects I decided to withold publication untill now, when I can put forward more concise ideas about the origin of maize, based on a new experimental reconstruction of the "wild type". 4) The two main aspects of MANGELSDORF and REEVES hypothesis are discussed. We agree with the authors that ST. HILAIRE's theory is probably correct in so far as the tunicata gene is a wild type relic gene, but cannot accept the reconstruction of wild corn as a homozygous pod corn with a hermaphroditic tassel. As shown experimentally (Fig. 2-3) these tassels have their central spike transformed into a terminal, many rowed ear with a flexible rachis, while possessing at the same time the lateral ear. Thus no explanation is given of the origin of the corn ear, which is the main feature of cultivated corn (BRIEGER, 1943). The second part of the hypothesis referring to the origin of Euchlaena from corn, inverting thus ASCHERSON's theory, cannot be accepted for several reasons, stated in some detail. The data at hand justify only the conclusion that both genera, Euchlaena and Zea, are related, and there is as little proof for considering the former as ancestor of the latter as there is for the new inverse theory. 5) The analysis of indigenous corn, which will be published in detail by BRIEGER and CUTLER, showed several very primitive characters, but no type was found which was in all characters sufficiently primitive. A genetical analysis of Paulista Pod Corn showed that it contains the same gene as other tunicates, in the IV chromosome, the segregation being complicated by a new gametophyte factor Ga3. The full results of this analysis shall be published elsewhere. (BRIEGER). Selection experiments with Paulista Pod Corn showed that no approximation to a wild ancestor may be obtained when limiting the studies to pure corn. Thus it seemed necessary to substitute "domesticated" by "wild type" modifiers, and the only means for achieving this substitution are hybridizations with Euchlaena. These hybrids have now been analysed init fourth generation, including backcrosses, and, again, the full data will be published elsewhere, by BRIEGER and ADDISON. In one present publication three forms obtained will be described only, which represent an approximation to wild type corn. 6) Before entering howewer into detail, some arguments against ST. HILAIRE's theory must be mentioned. The premendelian argument, referring to the instability of this character, is explained by the fact that all fertile pod corn plants are heterozygous for the dominant Tu factor. But the sterility of the homozygous TuTu, which phenotypically cannot be identified, is still unexplained. The most important argument against the acceptance of the Tunicata faetor as wild type relic gene was removed recently by CUTLER (not yet published) who showed that this type has been preserved for centuries by the Bolivian indians as a mystical "medicine". 7) The main botanical requirements for transforming the corn ear into a wild type structure are stated, and alternative solutions given. One series of these characters are found in Tripsacum and Euchlaena : 2 rows on opposite sides of the rachis, protection of the grains by scales, fragility of the rachis. There remains the other alternative : 4 rows, possibly forming double rows of female and male spikelets, protection of kernels by their glumes, separation of grains at their base from the cob which is thin and flexible. 8) Three successive stages in the reconstruction of wild corn, obtained experimentally, are discussed and illustrated, all characterized by the presence of the Tu gene. a) The structure of the Fl hybrids has already been described in 1943. The main features of the Tunicata hybrids (Fig. -8), when compared with non-tunicate hybrids (Fig. 5-6), consist in the absence of scaly protections, the fragility of the rachis and finally the differentiation of the double rows into one male and one female spikelet. As has been pointed out, these characters represent new phenotypic effects of the tunicate factor which do not appear in the presence of pure maize modifiers. b) The next step was observed among the first backcross to teosinte (Fig. 9). As shown in the photography, Fig. 9D, the features are essencially those of the Fl plants, except that the rachis is more teosinte like, with longer internodes, irregular four-row-arrangement and a complete fragility on the nodes. c) In the next generation a completely new type appeared (Fig. 10) which resembles neither corn nor teosinte, mainly in consequence of one character: the rachis is thin and flexible and not fragile, while the grains have an abscission layer at the base, The medium sized, pointed, brownish and hard granis are protected by their well developed corneous glumes. This last form may not yet be the nearest approach to a wild grass, and I shall try in further experiments to introduce other changes such as an increase of fertile flowers per spikelet, the reduction of difference between terminal and lateral inflorescences, etc.. But the nature of the atavistic reversion is alveadwy such that it alters considerably our expectation when looking for a still existing wild ancestor of corn. 9) The next step in our deductions must now consist in an reversion of our question. We must now explain how we may obtain domesticated corn, starting from a hypothetical wild plant, similar to type c. Of the several changes which must have been necessary to attract the attention of the Indians, the following two seem to me the most important: the disappearance of all abscission layers and the reduction of the glumes. This may have been brought about by an accumulation of mutations. But it seems much more probable to assume that some crossing with a tripsacoid grass or even with Tripsacum australe may have been responsible. In such a cross, the two types of abscission layer would be counterbalanced as shown by the Flhybrids of corn, Tripsacum and Euchlaena. Furthermore in later generations a.tu-allele of Tripsacum may become homozygous and substitute the wild tunicate factor of corn. The hypothesis of a hybrid origin of cultivated corn is not completely new, but has been discussed already by HARSHBERGER and COLLINS. Our hypothesis differs from that of MANGELSDORF and REEVES who assume that crosses with Tripsacum are responsible only for some features of Central and North American corn. 10) The following arguments give indirects evidence in support of our hypothesis: a) Several characters have been observed in indigenous corn from the central region of South America, which may be interpreted as "tripsacoid". b) Equally "zeoid" characters seem to be present in Tripsacum australe of central South-America. c) A system of unbalanced factors, combined by the in-tergeneric cross, may be responsible for the sterility of the wild type tunicata factor when homozygous, a result of the action of modifiers, brought in from Tripsacum together with the tuallele. d) The hybrid theory may explain satisfactorily the presence of so many lethals and semilethals, responsible for the phenomenon of inbreeding in cultivated corn. It must be emphasized that corn does not possess any efficient mechanism to prevent crossing and which could explain the accumulation of these mutants during the evolutionary process. Teosinte which'has about the same mechanism of sexual reproduction has not accumulated such genes, nor self-sterile plants in spite of their pronounced preference for crossing. 11) The second most important step in domestication must have consisted in transforming a four rowed ear into an ear with many rows. The fusion theory, recently revived byLANGHAM is rejected. What happened evidently, just as in succulent pXants (Cactus) or in cones os Gymnosperms, is that there has been a change in phyllotaxy and a symmetry of longitudinal rows superimposed on the original spiral arrangement. 12) The geographical distribution of indigenous corn in South America has been discussed. So far, we may distinguish three zones. The most primitive corn appears in the central lowlands of what I call the Central Triangle of South America: east of the Andies, south of the Amazone-Basin, Northwest of a line formed by the rivers São Prancisco-Paraná and including the Paraguay-Basin. The uniformity of the types found in this extremely large zone is astonishing (BRIEGER and CUTLER). To the west, there is the well known Andian region, characterized by a large number of extremely diverse types from small pop corn to large Cuszco, from soft starch to modified sweet corn, from large cylindrical ears to small round ears, etc.. The third region extends along the atlantic coast in the east, from the Caribean Sea to the Argentine, and is characterized by Cateto, an orange hard flint corn. The Andean types must have been obtained very early, and undoubtedly are the result of the intense Inca agriculture. The Cateto type may be obtained easily by crosses, for instance, of "São Paulo Pointed Pop" to some orange soft corn of the central region. The relation of these three South American zones to Central and North America are not discussed, and it seems essential first to study the intermediate region of Ecuador, Colombia and Venezuela. The geograprical distribution of chromosome knobs is rapidly discussed; but it seems that no conclusions can be drawn before a large number of Tripsacum species has been analysed.

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Based on the variables relationship and knowledge, this article aimed at analyzing how a multinational enterprise selects an entry mode to operate in a particular international market and how this initial choice evolves over time. We devised a rather new theoretical framework to address it by combining three theoretical approaches that have dealt with the firm internationalization: the Uppsala model, the relational approach, and the subsidiary development literature. We constructed a qualitative backward-looking longitudinal case study of the internationalization process of a North-American multinational enterprise in the Brazilian market. Results show that four types of relationships and three types of knowledge played the role in the events that characterized the internationalization of this firm. Based on these results, five new hypotheses concerning the interplay between relationships and knowledge in the internationalization process of the firm are suggested for future empirical tests.

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The literature shows that obesity is a public health problem concerning especially the general paediatrician. While prevention has probably more chances of success than treatment, drugs or, in case of failure, the surgical approach are reserved for extreme cases. In the domain of infectiology the different laboratory tests allow only partially to diagnose severe infections. But in the context of a potential influenza pandemic rapid virologic tests become more and more important. They allow a more precise diagnosis and a reduction of hospitalisations and of antibiotic prescriptions. A review of the north American experience with the pneumococal vaccine shows that the heptavalent vaccine will change our approach in infants with fever in whom we suspect a severe infection.

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Cette thèse cible l'étude de la structure thermique de la croûte supérieure (<10km) dans les arcs magmatiques continentaux, et son influence sur l'enregistrement thermochronologique de leur exhumation et de leur évolution topographique. Nous portons notre regard sur deux chaînes de montagne appartenant aux Cordillères Américaines : Les Cascades Nord (USA) et la zone de faille Motagua (Guatemala). L'approche utilisée est axée sur la thermochronologie (U-Th-Sm)/He sur apatite et zircon, couplée avec la modélisation numérique de la structure thermique de la croûte. Nous mettons en évidence la variabilité à la fois spatiale et temporelle du gradient géothermique, et attirons l'attention du lecteur sur l'importance de prendre en compte la multitude des processus géologiques perturbant la structure thermique dans les chaînes de type cordillère, c'est à dire formées lors de la subduction océanique sous un continent.Une nouvelle approche est ainsi développée pour étudier et contraindre la perturbation thermique autour des chambres magmatiques. Deux profiles âge-elevation (U-Th-Sm)/He sur apatite et zircon, ont été collectées 7 km au sud du batholithe de Chilliwack, Cascades Nord. Les résultats montrent une variabilité spatiale et temporelle du gradient géothermique lors de l'emplacement magmatique qui peut être contrainte et séparé de l'exhumation. Durant l'emplacement de l'intrusion, la perturbation thermique y atteint un état d'équilibre (-80-100 °C/km) qui est fonction du flux de magma et de ia distance à la source du magma, puis rejoint 40 °C/km à la fin du processus d'emplacement magmatique.Quelques nouvelles données (U-Th)/He, replacées dans une compilation des données existantes dans les Cascades Nord, indiquent une vitesse d'exhumation constante (-100 m/Ma) dans le temps et l'espace entre 35 Ma et 2 Ma, associée à un soulèvement uniforme de la chaîne contrôlé par l'emplacement de magma dans la croûte durant toute l'activité de l'arc. Par contre, après ~2 Ma, le versant humide de la chaîne est affecté par une accélération des taux d'exhumation, jusqu'à 3 km de croûte y sont érodés. Les glaciations ont un triple effet sur l'érosion de cette chaîne: (1) augmentation des vitesses d'érosion, d'exhumation et de soulèvement la où les précipitations sont suffisantes, (2) limitation de l'altitude contrôlé par la position de Γ Ε LA, (3) élargissement du versant humide et contraction du versant aride de la chaîne.Les modifications des réseaux de drainage sont des processus de surface souvent sous-estimés au profil d'événements climatiques ou tectoniques. Nous proposons une nouvelle approche couplant une analyse géomorphologique, des données thermochronologiques de basse température ((U-Th-Sm)/He sur apatite et zircon), et l'utilisation de modélisation numérique thermo-cinématique pour les mettre en évidence et les dater; nous testons cette approche sur la gorge de la Skagit river dans les North Cascades.De nouvelles données (U-Th)/He sur zircons, complétant les données existantes, montrent que le déplacement horizontal le long de la faille transformante continentale Motagua, la limite des plaques Caraïbe/Amérique du Nord, a juxtaposé un bloc froid, le bloc Maya (s.s.), contre un bloque chaud, le bloc Chortis (s.s.) originellement en position d'arc. En plus de donner des gammes d'âges thermochronologiques très différents des deux côtés de la faille, le déplacement horizontal rapide (~2 cm/a) a produit un fort échange thermique latéral, résultant en un réchauffement du côté froid et un refroidissement du côté chaud de la zone de faille de Motagua.Enfin des données (U-Th-Sm)/He sur apatite témoignent d'un refroidissement Oligocène enregistré uniquement dans la croûte supérieure de la bordure nord de la zone de faille Motagua. Nous tenterons ultérieurement de reproduire ce découplage vertical de la structure thermique par la modélisation de la formation d'un bassin transtensif et de circulation de fluides le long de la faille de Motagua. - This thesis focuses on the influence of the dynamic thermal structure of the upper crust (<10km) on the thermochronologic record of the exhumational and topographic history of magmatic continental arcs. Two mountain belts from the American Cordillera are studied: the North Cascades (USA) and the Motagua fault zone (Guatemala). I use a combined approach coupling apatite and zircon (U-Th-Sm}/He thermochronology and thermo- kinematic numerical modelling. This study highlights the temporal and spatial variability of the geothermal gradient and the importance to take into account the different geological processes that perturb the thermal structure of Cordilleran-type mountain belts (i.e. mountain belts related to oceanic subduction underneath a continent}.We integrate apatite and zircon (U-Th)/He data with numerical thermo-kinematic models to study the relative effects of magmatic and surface processes on the thermal evolution of the crust and cooling patterns in the Cenozoic North Cascades arc (Washington State, USA). Two age-elevation profiles that are located 7 km south of the well-studied Chiliiwack intrusions shows that spatial and temporal variability in geothermal gradients linked to magma emplacement can be contrained and separated from exhumation processes. During Chiliiwack batholith emplacement at -35-20 Ma, the geothermal gradient of the country rocks increased to a very high steady-state value (80-100°C/km), which is likely a function of magma flux and the distance from the magma source area. Including temporally varying geothermal gradients in the analysis allows quantifying the thermal perturbation around magmatic intrusions and retrieving a relatively simple denudation history from the data.The synthesis of new and previously published (U-Th)/He data reveals that denudation of the Northern Cascades is spatially and temporally constant at -100 m/Ma between ~32 and ~2 Ma, which likely reflects uplift due to magmatic crustal thickening since the initiation of the Cenozoic stage of the continental magmatic arc. In contrast, the humid flank of the North Cascades is affected by a ten-fold acceleration in exhumation rate at ~2 Ma, which we interpret as forced by the initiation of glaciations; around 3 km of crust have been eroded since that time. Glaciations have three distinct effects on the dynamics of this mountain range: (1) they increase erosion, exhumation and uplift rates where precipitation rates are sufficient to drive efficient glacial erosion; (2) they efficiently limit the elevation of the range; (3) they lead to widening of the humid flank and contraction of the arid flank of the belt.Drainage reorganizations constitute an important agent of landscape evolution that is often underestimated to the benefit of tectonic or climatic events. We propose a new method that integrates geomorphology, low-temperature thermochronometry (apatite and zircon {U-Th-Sm)/He), and 3D numerical thermal-kinematic modelling to detect and date drainage instability producing recent gorge incision, and apply this approach to the Skagit River Gorge, North Cascades.Two zircon (U-Th)/He age-elevation profiles sampled on both sides of the Motagua Fault Zone (MFZ), the boundary between the North American and the Caribbean plates, combined with published thermochronological data show that strike-slip displacement has juxtaposed the cold Maya block (s.s.) against the hot, arc derived, Chortis block (s.s ), producing different age patterns on both sides of the fault and short-wavelength lateral thermal exchange, resulting in recent heating of the cool side and cooling of the hot side of the MFZ.Finally, an apatite (U-Th-Sm)/He age-elevation profile records rapid cooling at -35 Ma localized only in the upper crust along the northern side of the Motagua fault zone. We will try to reproduce these data by modeling the thermal perturbation resulting from the formation of a transtensional basin and of fluid flow activity along a crustal- scale strike-slip fault.

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The study aimed to find scientific evidence about the duration of preoperative smoking cessation required to reduce surgical wound healing complications. An integrative review was performed in the databases, Latin American and Caribbean Literature on Health Sciences (LILACS) and Medical Literature Analysis and Retrieval System Online (MEDLINE), from 08/17/2012 to 09/17/2012, using the keywords: tobacco use cessation and wound healing; tobacco use cessation and preoperative period; tobacco use cessation and perioperative period (LILACS) and tobacco use cessation and perioperative period; tobacco use cessation and wound healing (MEDLINE). Out of the 81 eligible studies, 12 were included. The duration of smoking cessation needed to reduce healing complications was at least four weeks (four studies with level of evidence I, three studies with level of evidence II, two studies with level of evidence IV, and one study with level of evidence VII).