894 resultados para Fragmentation
Resumo:
Since the mid 90's, international actors as well as governmental actors have raised their interest into the development of irrigation's potential that is still largely unexploited in Niger. It seems all the more interesting as it could answer the needs of a fast growing population (3.3% per year). However, if everyone agrees on the need to development this system, the current implementation triggers questions on the process itself and its side effects. National and international policies on this matter were build upon an historical process through colonial, post-colonial and then the late 1980's neoliberal structures, leading to a business model that reveals a discrepancy between the state logic and the farming one. This business model asks for a high capacity of mobilization of resources unachievable for many, especially when they want to address small-scale irrigation (area <l-2ha). This research aims at exploring the linkage between the small-scale irrigation and the evolution of land tenure systems. The empirical analysis raise three main questions that concern the issue of secure land rights through the modern law, the commoditization of land and land access for the producers. The department of Gaya has a large potential of accessible water resources that allowed an extensive production of fruits and vegetables since the 1980's. These productions were developed at first by the local farmers, but the high value added engendered then attracted external players as well, such as civil servants and merchants. The World Bank supported this momentum through the development of a business type project. Unfortunately, it reached mostly the new external players and local elites rather than the small farmers, notably due to the high illiteracy rate among farmers. In terms of land tenure analysis, the project excluded all farmers cultivating land on a loan or lease agreement and all those for whom it was difficult to obtain a title of ownership. However, this new interest for small-scale irrigation exerted by the project and the new players triggered the commoditization of land. As a matter of fact, the demographic constraints and the fragmentation of the familial land ownership led to a more individual production system, where the customary relation to land tenure is weakened or even overcome. This makes it easier for the new players who need to settle their small-scale irrigation projects to purchase land. When there are only few areas available for selling, the. purchasing processes are undermining the farmers with insecure rights. If the withdrawal of lands is supposed to be smoothened by social measures, such as replacement of the land and primary offers to purchase the land, those measures are often not attractive. The proposed land of replacement is frequently too far away located or lesser fertile to be of any use and the economic capacity of purchasing is too little, eventually leading the farmers to leave their terroirs. Those in charge of the application of the Rural Code have succeeding in answering the need of written secured land tenure, but have difficulty to meet the challenge of doing the same to secure rights for farmers with loans or lease agreements. The small-scale irrigation could bring an answer for their financial needs to buy the land, but it would require mobilizing resources to invest or an easier access to supportive projects. The economic benefice from small-scale irrigation is now widely recognized, but we have to take also into account the risks of marginalization of part of the small farmers. For a more widely spread exploitation of small-scale irrigation, the mechanism of land regulation as well as the process to access the financial and technical support of projects must be revised in order to reach more small farmers. Dveloppement de l'irrigation et volution des rgimes fonciers dans la rgion de Gaya (Niger) - Le secteur de l'irrigation a bnfici d'un regain d'intrt de la part des acteurs internationaux du dveloppement et de l'Etat nigrien depuis le milieu des annes 1990. Cet intrt est la hauteur du potentiel en terres irrigables (300Ό00 ha environ) du pays, largement sous-exploit alors que les besoins alimentaires sont grandissants, la population augmentant de 3.3% par an. Si le diagnostic est correct, les stratgies mises en oeuvre en matire d'irrigation posent question. Les interventions, aussi bien publiques qu'internationales, reposent sur un modle entrepreneurial qui parachve une longue trajectoire historique. Initie par l'Etat colonial, poursuivie par l'Etat post-colonial et transform par les politiques nolibrales des annes 1980, elle se caractrise par un hiatus constant entre logiques tatiques et logiques paysannes. En matire de petite irrigation prive (surfaces < 1-2 ha, technologies faible cot), ce modle prsuppose une mobilisation de ressources (conomiques, sociales, ducationnelles et foncires) ingalement rparties au sein de la population rurale. Cette recherche s'est intresse expliciter les liens qui existent entre le dveloppement de la petite irrigation prive et l'volution des rgimes fonciers. Les trois questionnements qui ont guid l'analyse empirique portent sur la scurisation foncire, les dynamiques de marchandisation de la terre et l'accs la terre pour tous les producteurs. Le Dpartement de Gaya dispose d'un potentiel trs important en ressources hydriques, facilement mobilisables. Les productions marachres et fruitires ont connu un essor trs important partir des annes 1980. Initialement pratiques par les cultivateurs, elles ont progressivement attir l'attention d'acteurs externes au monde rural (fonctionnaires, commerants), du fait de leur haute valeur ajoute. La Banque mondiale a fortement soutenu cette dynamique travers un projet vocation entrepreneuriale, qui s'est pourtant rvl hors de porte de la majorit des petits paysans et a principalement bnfici ces acteurs extra-ruraux ainsi qu' certaines lites locales. Au plan foncier, il a en particulier exclu tous les emprunteurs des terres, qui ne sont pas mme de produire des documents crits confirmant leurs droits sur la terre. Ce projet, et plus largement l'intrt que les acteurs extra-ruraux portent la petite irrigation, ont contribu alimenter la marchandisation de la terre. Sans ancrage familial dans les terroirs villageois, ces acteurs sont obligs d'acheter la terre pour faire de l'irrigation. Leur demande vient s'inscrire dans un contexte gnral o la pression dmographique et le morcellement successif des capitaux fonciers familiaux ont progressivement individualis la relation entre les producteurs et la terre, au point d'affaiblir ou de faire tomber les interdits coutumiers en matire de vente. Dans les espaces disposant de faibles rserves foncires, les ventes se font principalement au dtriment des acteurs qui, comme les emprunteurs, disposent de droits fonciers peu stables et scuriss. Si le retrait de la terre est socialement encadr (terre en remplacement, possibilit d'acheter la terre qui va tre vendue), il pose galement des contraintes agronomiques (sols de moindre qualit) et conomiques (ncessit de disposer des liquidits pour racheter la terre) qui peuvent, en dernier ratio, obligent les acteurs concerns quitter les terroirs. Les instances du Code rural, qui ont su apporter des rponses satisfaisantes la demande de scurisation foncire par l'tablissement de documents crits, rencontrent aujourd'hui de grandes difficults en faire de mme pour les droits de prt. Dans ce contexte, l'irrigation peut apporter les sommes ncessaires l'achat des terres. Encore faut-il que ces emprunteurs disposent des ressources financires propres pour la dvelopper ou qu'ils puissent y avoir accs grce l'appui d'un projet. Si l'intrt conomique de la petite irrigation prive est indiscutable, les risques de marginalisation d'une partie de producteurs ruraux qu'elle peut produire sont bien rels. Pour en faire une activit accessible au plus grand nombre, il faut revoir les mcanismes de rgulation foncire, ainsi que les montages techniques et financiers qui supportent le dveloppement de ce secteur d'activit trs prometteur.
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Abstract Invasive species represent with fragmentation of habitat the most serious threats to biodiversity in the world. Galpagos Archipelago, as most oceanic islands, suffers a high rate of introduced animals and plants that affect equilibrium and biodiversity of this unique biota. Ants rank among the most devastating invaders. Their social organization confer them a high ability to adapt and to spread in new environments forming rapidly populous communities. We studied the ant community of Floreana Island composed mainly of introduced species (at least 1 S). Introduction events occurred successively during last century. The last record is Monomorium destructor arrived in the eighties. Our aim is to investigate the modalities of interaction and coexistence of these introduced species. We highlighted the competition hierarchy of the coexisting species using attractive food baits. Two species behave as competitively dominant by monopolizing an important part of resources. They are M. destructor restricted to a small area and the fire ant Solenopsis geminata widely distributed on the island. Then we evaluated the relative importance of abiotic factors and interspecific competition in structuring the community. Ecological data were collected and presence and abundance of species were estimated using different methods in a wide range of habitats. Several species showed preferences either for arid or for humid areas. The little fire ant Wasmannia auropunctata, awell-known devastating species when introduced, was exclusively found in moist habitat in and around the agricultural area situated in the upper and central part of th island. It coexists with other species in several parts but in a restricted perimeter it excludes all other ants and worker's density on the ground is nearly 70 times higher than ant's density in similar habitats occupied by several species. But most opportunist tramp species establish everywhere without particular ecological requirement. Analyses of species co-occurrences at various levels didn't reveal any marked effect of competition in structuring ant's assemblages. We supposed that the lack ofcompetition-derived structure has to be attributed to the dynamic of the system. Indeed, across the successive census of 1996, 2003, 2004 and 2005, species distributions and abundances appeared to be highly variables. In particular harsh conditions occurring in dry season in certain parts seem to be limiting to S. geminatai. We suggest that huge variations in the local distribution of the dominant S. geminata disrupt the community organization. Finally we conducted artificial ant confrontations to evaluate to what extend an aggressive behavior at the worker level maybe linked to the ecological success of a species on the island. S. geminata was rather indifferent when confronted to a submissive species on food sources, suggesting that its competitive dominance is largely due to a numerical superiority. On the other hand M. destructor exhibits a strong agonistic behavior in similar confrontations. As soon as the presence of a competitor is detected, most workers were observed to abandon foraging and to take part in physical aggressions. Since it is still restricted nearby its introduction spot two decades after its arrival, we suggest that the energetic cost of such an aggressive behavior prevent it to spread on that island already highly colonized. Dominant invasive species such as the fire ants S. geminata and W. auropunctata have negative impacts on Galpagos fauna, disturbing the hatching of land tortoises and birds. But very little is known about the impact of other exotic ants. Indeed, impact on arthropods and generally on ground-dwelling organisms is very diffcult to evaluate. As a consequence of the dynamic character of Floreana I. ant community it is difficult to build models or to mlce predictions on evolution of introduced ant fauna. But Camponotus macilentus, an abundant endemic species seems today to be little affected by introduced ant species thanks to its strong interference competition ability and its preference for arid and harsh environments. Rsum Les espces envahissantes reprsentent, avec la fragmentation du paysage, la plus grande menace pour la biodiversit. L'archipel des Galpagos, comme la plupart des les du Pacifique, compte un grand nombre d'espces introduites qui menacent la biodiversit de ce milieu unique.. Les fourmis sont parmi les envahisseurs les plus dvastateurs. Leur organisation sociale leur permet de s'adapter et de se propager pour devenir rapidement abondantes. Nous avons tudi la communaut de fourmis sur l'le de Floreana principalement compose d'espces introduites (au moins 15). Les introductions se sont succdes au cours du sicle prcdent. La dernire espce recense est Monomorium destructor introduite dans les annes 80. Notre objectif est de mettre jour les modalits des interactions et de la coexistence de ces espces introduites. Nous avons mis en vidence la hirarchie de comptition des diffrentes espces l'aide d'appts de nourriture. Deux espces se comportent de faon dominante en monopolisant une part importante des ressources. Ce sont M. destructor, restreintes un petit primtre, et la fourmi de feu Solenopsis geminata, largement distribue sur l'le. Nous avons valu l'importance relative des facteurs abiotiques et de la comptition interspcifique dans la structuration des peuplements. Des donnes cologiques ont t collectes et la prsence et l'abondance des espces ont t estimes l'aide de trois mthodes au sein d'une grande diversit d'habitats. Plusieurs espces .montrent des prfrences soit pour les milieux humides, soit pour les milieux arides. La petite fourmi de feu Wasmannia auropunctata, une espce connue pour tre dvastatrice dans ses sites d'introduction, est prsente exclusivement dans les habitats humides dans et proximit de la zone agricole situe dans la partie centrale de l'le. Elle coexiste en plusieurs points avec d'autres espces mais au sein d'un primtre restreint elle exclut toute autre fourmi et atteint des densits record au sol presque 70 fois suprieures aux densits de fourmis observes sur les sites voisins occups par plusieurs espces. Mais la plupart des espces vagabondes opportunistes s'tablissent partout sans exigences cologiques particulires. Des analyses de cooccurrence d'espces plusieurs niveaux n'ont pas rvl de rle marqu de la comptition dans la structuration des communauts. Nous supposons que l'absence d'une telle structure doit tre attribue la dynamique du systme. En effet, au cours des diffrents recensements de 1996-1997, 2003, 2004 et 2005, la distribution et l'abondance des espces tait trs variable. En particulier, les conditions rudes qui rgnent dans la zone aride durant la saison sche semblent affecter particulirement S. geminata. Nous suggrons que de fortes variations dans la distribution de l'espce dominante perturbent l'orgaisation des communauts. Finalement nous avons effectu des confrontations artificielles pour valuer dans quelle mesure un comportement agressif au niveau de l'ouvrire peut tre li au succs cologique d'une espce sur l'le. S. geminata montre trs peu de raction face une espce subordonne sur une mme source de nourriture, ce qui laisse supposer que sa dominance est largement due sa supriorit numrique. Par contre, dans des conditions similaires, M. destructor est fortement agressive. En prsence d'un comptiteur, la plupart des ouvrires renoncent trs vite leur activit de fourragement pour agresser les individus de l'autre espce. Puisque deux dcennies aprs son introduction elle est toujours confine son point d'arrive, nous supposons que le cot en nergie et en ouvrires de ce comportement trs agressif est un obstacle son expansion sur cette le dj fortement colonise. Les espces envahissantes dominantes comme les fourmis de feu S. geminata et W. auropunctata sont connues pour leur impact ngatif sur la faune des Galpagos, entre autre sur les jeunes des tortues terrestres et des oiseaux. Mais nous savons trs peu de choses sur l'impact des autres espces de fourmis introduites. En effet, l'impact sur les arthropodes, et plus gnralement sur la faune du sol, est trs difficile valuer. En raison du caractre dynamique de la communaut de fourmi de Floreana, il est difficile de construire des modles et de faire des prdictions sur l'volution des peuplements de fourmis introduites. Mais Camponotus macilentus, une espce endmique abondante, semble aujourd'hui peu affecte par les espces introduites grce ses capacits de comptition par interfrence et sa prfrence pour les milieux arides. Resumen Las, especies invasoras representan, junto con la fragmentacin del paisaje, la mayor amenaza para la biodiversidad. El archipilago de Galpagos, como la mayora de las islas del Pacfico, cuenta con un gran nmero de especies introducidas que amenazan la biodiversidad de este lugar nico. Las hormigas son uno de los invasores ms devastadores. Su organizacin social les permite adaptarse y propagarse para ser rpidamente abundante. Estudiamos la comunidad de hormigas de la isla Floreana principalmente compuesta de especies introducidas (al menos 15). Las introducciones se sucedieron durante el siglo anterior. La ltima especie contabilizada es Monomorium destructor introducida en los aos 80. Nuestro objetivo es poner al da las modalidades de las interacciones y de la coexistencia de estas especies introducidas. Pusimos de relieve la jerarqua de competencia de las distintas especies con ayuda de cebos de comida. Dos especies se implican de manera dominante monopolizando una parte importante de los recursos. Son M. destructor, limitado a un pequeo permetro, y la hormiga de fuego Solenopsis geminata; ampliamente distribuida por la isla. Evaluamos la importancia relativa de los factores abiticos y de la competencia interespecfica en la estructuracin de la communidad. Se recogieron algunos datos ecolgicos y se consideraron la presencia y la abundancia de las especies con ayuda de tres mtodos en una gran diversidad de hbitats. Varias especies muestran preferencias o por los medios hmedos, o por los medios ridos. La pequea hormiga de fuego Wasmannia auropunctata, una especie conocida por ser devastadora en sus lugares de introduccin, est presente exclusivamente en los hbitats hmedos y cerca de la zona agrcola situada en la parte central de la isla. Coexiste en varios puntos con otras especies pero en un permetro limitado excluye a cualquier otra hormiga y alcanza densidades en el suelo casi 70 veces superiores a las densidades de hormigas observadas en los lugares vecinos ocupados por varias especies. Pero la mayora de las especies vagabundas oportunistas se establecen por todas partes sin exigencias ecolgicas particulares. Anlisis de cooccurrenca de las especies a varios niveles no revelaron una grande importanca de la competencia en la estructuracin de las comunidades. Suponemos que la ausencia de tal estructura Beb ser por la dinmica del sistema. Efectivamente, durante los distintos censos de 1996-1997, 2003,.2004 y 2005, la distribucin ? la abundancia de las especies eran muy variables. En particular, las condiciones drsticas que reinan en la zona rida durante la temporada seca parecen afectar especialmente a S. geminata. Sugerimos que fuertes variaciones en la distribucin de la especie dominante perturben la organizacin de las comunidades. Finalmente efectuamos confrontaciones artificiales para evaluar hast que punto un comportamiento agresivo a nivel de la obrera puede explicar el xito ecolgico de una especie en la isla. S. geminata muestra muy poca reaccin ante una especie subordinada mientras comparten la misma comida, lo que deja suponer que su dominancia se debe a su superioridad numrica. Por el contrario, en condiciones similares, M. destructor es muy agresivo. En presencia de otra especie, la mayra de las obreras renuncian muy rpidamente a alimentarse para atacar a los individuos de la otra especie. Puesto que dos dcadas despus de su introduccin todava se confina en su punto de llegada, suponemos que el coste en energa y en obreras de este comportamiento muy agresivo es un obstculo a su extensin en esta isla ya muy colonizada. Las especis invasoras dominantes como las hormigas de fuego S. geminata y W. auropunctata son conocidas por su impacto negativo en la fauna de Galpagos, entre otras cosas sobre los juveniles de las tortugas terrestres y pjaros. Pero sabemos muy poco sobre el impacto de las otras especies de hormigas introducidas. Efectivamente es muy difcil de evaluar el impacto en los artrpodos, y ms generalmente en la fauna del suelo. Debido al carcter dinmico de la comunidad de hormiga de Floreana, es diEcil construir modelos y hacer predicciones sobre la evolucin de las poblaciones de hormigas introducidas. Pero Camponotus macilentus, una especie endmica abundante, parece poco afectad hoy por las especies introducidas gracias a sus capacidades de competencia por interferencia y su preferencia por los medios ridos.
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BACKGROUND: As little such data is available in African populations, we investigated the prevalence of ADPKD and the impact of the disease in the Seychelles islands, where approximately 65% of the population is of African descent and 30% of Caucasian or mixed descent. METHODS: Prevalent cases were identified over a 3-year period by requesting all the doctors in the country (most of them are employed within a national health system) to refer all presumed or confirmed cases and by systematically examining the family members of all confirmed cases. The diagnosis was based on standard criteria including ultrasonographic findings and family history. RESULTS: Forty-two cases were identified in this population of 74,331 inhabitants, a total prevalence (per 100,000 total population) of 57 (95% CI, 41-76). All but one of the cases were of Caucasian descent so that the prevalence rates of the disease in the populations of Black and Caucasian descents were respectively 2 (0-11) and 184 (132-249). The prevalence rates of the gene(s) carriers were estimated to be 75 (45-117) in the total population respectively 6 (0-33) and 236 (140-372) in the Black and Caucasian populations. Haplotype analysis in 58 cases from three families showed a common DNA fragment in all affected individuals. Cases had significantly higher blood pressure compared to the general population and 21% had serum creatinine higher than 120 mumol/l. Among the established pedigrees, mean age of death between 1960 and 1995 (haemodialysis was introduced in 1992) was younger in subjects with than those without ADPKD (50.5 vs 67.7 years; P < 0.001). CONCLUSIONS: In the Seychelles, ADPKD clusters in the Caucasian population (possibly a founder effect), is rare in individuals of black descent, and is associated with substantial clinical and survival impact.
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The properties and cosmological importance of a class of non-topological solitons, Q-balls, are studied. Aspects of Q-ball solutions and Q-ball cosmology discussed in the literature are reviewed. Q-balls are particularly considered in the Minimal Supersymmetric Standard Model with supersymmetry broken by a hidden sector mechanism mediated by either gravity or gauge interactions. Q-ball profiles, charge-energy relations and evaporation rates for realistic Q-ball profiles are calculated for general polynomial potentials and for the gravity mediated scenario. In all of the cases, the evaporation rates are found to increase with decreasing charge. Q-ball collisions are studied by numerical means in the two supersymmetry breaking scenarios. It is noted that the collision processes can be divided into three types: fusion, charge transfer and elastic scattering. Cross-sections are calculated for the different types of processes in the different scenarios. The formation of Q-balls from the fragmentation of the Aflieck-Dine -condensate is studied by numerical and analytical means. The charge distribution is found to depend strongly on the initial energy-charge ratio of the condensate. The final state is typically noted to consist of Q- and anti-Q-balls in a state of maximum entropy. By studying the relaxation of excited Q-balls the rate at which excess energy can be emitted is calculated in the gravity mediated scenario. The Q-ball is also found to withstand excess energy well without significant charge loss. The possible cosmological consequences of these Q-ball properties are discussed.
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Can rules be used to shield public resources from political interference? The Brazilian constitution and national tax code stipulate that revenue sharing transfers to municipal governments be determined by the size of counties in terms of estimated population. In this paper I document that the population estimates which went into the transfer allocation formula for the year 1991 were manipulated, resulting in significant transfer differentials over the entire 1990's. I test whether conditional on county characteristics that might account for the manipulation, center-local party alignment, party popularity and the extent of interparty fragmentation at the county level are correlated with estimated populations in 1991. Results suggest that revenue sharing transfers were targeted at right-wing national deputies in electorally fragmented counties as well as aligned local executives.
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Depuis 1990 et la fin de la Guerre Froide, les Etats-Unis d'Amrique sont devenus la premire puissance mondiale, anime par l'idal de dfendre les valeurs occidentale et de rpandre la dmocratie dans le monde. Or, entre des racines identitaires grco-romaines empruntes l'Europe, et les guerres menes au Moyen-Orient contre diffrents ennemis, la mission de l'Amrique suscite critiques et interrogations, et le conflit est autant culturel que militaire. L'Iliade d'Homre au contenu guerrier, rige par la tradition littraire en oeuvre fondatrice de l'Occident, offre aux penseurs amricains de tous horizons un outil de rflexion propre clairer ce prsent si inconfortable. A travers l'tude d'un corpus tripartite indit, ce travail se propose de questionner le rle d'une oeuvre symbolique de l'Antiquit grecque dans le monde d'aujourd'hui, et dbouche sur une rflexion plus large touchant au sens contemporain des tudes classiques et la transmission du savoir au sein de la culture populaire. Dans un premier temps, elle examine des ouvrages ou articles vocation scientifique, mais publis pour la plupart hors du cadre acadmique, qui thorisent et expriment les enjeux des guerres des cultures amricaines ( culture wars ) divisant conservateurs et libraux sur la mission vritable d'une ducation librale. Ces ouvrages se servent galement de l'Iliade comme d'un miroir o se reflte les conflits modernes, afin d'attnuer le trouble contemporain en juxtaposant pass et prsent. Dans un deuxime temps sont abords les mdias journalistiques et informatiques, l'aide des rsultats obtenus lors de recherches pousses, effectues dans les archives informatiques des journaux publis dans les capitales et villes majeures des cinquante Etats amricains. De fascinantes comparaisons entre la guerre de Troie et la guerre en Irak y sont notamment construites. Le discours sur l'actualit se dveloppe par le recours l'Antiquit, et en tire de nombreuses leons destines au gouvernement amricain et tous les meneurs de guerres. Et dans un troisime temps, deux romans de science-fiction, Ilium (2003) et sa suite Olympos (2005), de Dan Simmons, fournissent un fascinant complment littraire au reste du corpus. Imprgns par les culture wars, ils transposent l'Iliade dans un lointain futur et expriment sous une forme nouvelle toutes les interrogations brlantes qui, aujourd'hui particulirement, animent une Amrique trouble tant par ses guerres que par la remise en question de son identit occidentale. Par cette runion de trois domaines dissemblables, ce travail pose aussi de nombreuses questions pistmologiques sur la circulation de l'information, la transformation des savoirs, le flou des frontires entre les genres, la rvolution que reprsente Internet, et la fragmentation progressive de la bulle acadmique. Il propose galement de nombreuses perspectives d'ouverture permettant de poursuivre cette recherche. Car la rception contemporaine de l'Iliade - et de l'Antiquit en gnral - est un domaine riche et dynamique, qui prsente l'avantage - ou l'inconvnient, c'est selon - d'tre toujours d'actualit. L'inconfort du prsent ne devrait pas empcher son tude, car les rsultats sont extrmement rvlateurs de la vritable relation qu'entretiennent les hommes d'aujourd'hui - et non plus seulement les savants - avec leur pass.
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BACKGROUND: The mammalian target of rapamycin (mTOR) is frequently activated in colon cancers due to mutations in the phosphatidylinositol 3-kinase (PI3K) pathway. Targeting mTOR with allosteric inhibitors of mTOR such as rapamycin reduces colon cancer progression in several experimental models. Recently, a new class of mTOR inhibitors that act as ATP-competitive inhibitors of mTOR, has been developed. The effectiveness of these drugs in colon cancer cells has however not been fully characterized. METHODS: LS174T, SW480 and DLD-1 colon cancer cell lines were treated with PP242 an ATP-competitive inhibitor of mTOR, NVP-BEZ235, a dual PI3K/mTOR inhibitor or rapamycin. Tumor cell growth, proliferation and survival were assessed by MTS assay, 5-bromo-2'-deoxyuridine (BrDU) incorporation or by quantification of DNA fragmentation respectively. In vivo, the anticancer activity of mTOR inhibitors was evaluated on nude mice bearing colon cancer xenografts. RESULTS: PP242 and NVP-BEZ235 reduced the growth, proliferation and survival of LS174T and DLD-1 colon cancer cells more efficiently than rapamycin. Similarly, PP242 and NVP-BEZ235 also decreased significantly the proliferation and survival of SW480 cells which were resistant to the effects of rapamycin. In vivo, PP242 and NVP-BEZ235 reduced the growth of xenografts generated from LS174T and SW480 cells. Finally, we also observed that the efficacy of ATP-competitive inhibitors of mTOR was enhanced by U0126, a MEK inhibitor. CONCLUSIONS: Taken together, these results show that ATP-competitive inhibitors of mTOR are effective in blocking colon cancer cell growth in vitro and in vivo and thus represent a therapeutic option in colon cancer either alone or in combination with MEK inhibitors.
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Objective Evaluating the performance of primary care services for the treatment of tuberculosis according to the assessment referential of health services (structure/process) in Cabedelo, a port city in the state of Paraíba. Method An evaluation quantitative, cross-sectional study, in which were carried out 117 interviews with health professionals using a structured instrument. The analysis was based on the construction of indicators using a standardized value for the reduced variable (z=1). Results The structural indicators showed regular performance for the following variables: professional training, access to record instruments and coordination with other services. The process indicators related to external actions and information about the disease had unsatisfactory performance. The directly observed treatment and the flows of reference/counter-reference had regular performance. Conclusion The focused professional qualification, the fragmentation of practices and the unsystematic home care constitute obstacles for carrying out actions aimed at providing expanded, continuous and resolute care.


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This article is based on a study of a reform in the organisation of maternity services in the United Kingdom, which aimed towards developing a more woman-centred model of care. After decades of fragmentation and depersonalisation of care, associated with the shift of birth to a hospital setting, pressure by midwives and mothers prompted government review and a relatively radical turnaround in policy. However, the emergent model of care has been profoundly influenced by concepts and technologies of monitoring. The use of such technologies as ultrasound scans, electronic foetal monitoring and oxytocic augmentation of labour, generally supported by epidural anaesthesia for pain relief, have accompanied the development of a particular ecological model of birth – often called active management –, which is oriented towards the idea of an obstetric norm. Drawing on analysis of women’s narrative accounts of labour and birth, this article discusses the impact on women’s embodiment in birth, and the sources of information they use about the status of their own bodies, their labour and that of the child. It also illustrates how the impact on women’s experiences of birth may be mediated by a relational model of support, through the provision of caseload midwifery care.
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In 1500, Europe was composed of hundreds of statelets and principalities, with weak central authority,no monopoly over the legitimate use of violence, and overlapping jurisdictions. By 1800, only ahandful of powerful, centralized nation states remained. We build a model that explains both the emergenceof capable states and growing divergence between European powers. We argue that the impactof war was crucial for state building, and depended on: i) the financial cost of war, and ii) a country sinitial level of domestic political fragmentation. We emphasize the role of the "Military Revolution",which raised the cost of war. Initially, this caused more cohesive states to invest in state capacity, whilemore divided states rationally dropped out of the competition, causing divergence between Europeanstates. As the cost of war escalated further, all states engaged in a "race to the top" towards greater statebuilding.
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L'article dcrypte certains rouages de l'expatriation des joueurs africains vers l'Europe. La prcocit de leur migration et la fragmentation de leur trajectoire sont expliques par les spculations dont ils font l'objet. Les rseaux socio-conomiques qui portent les filires spculatives sont mis en lumire, ce qui permet de comprendre en particulier le rle primordial qu'y jouent les clubs intermdiaires europens, et maintenant asiatiques, intermdiaires dans la chane haute valeur ajoute, au taux d'viction le plus lev du monde. This paper decodes various workings at play in the expatriation of African players to Europe. The early nature of their migration and the fragmentation of their trajectories are explained by the speculation that surrounds them. The socio-economic networks that carry speculative channels are brought to light, which helps us to understand in particular the major role played by the European, and now Asian, clubs, which serve as intermediaries in the high value-added chain, with the highest "eviction rate" in the world.
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This paper ia an attempt to clarify the relationship between fractionalization,polarization and conflict. The literature on the measurement of ethnic diversityhas taken as given that the proper measure for heterogeneity can be calculatedby using the fractionalization index. This index is widely used in industrialeconomics and, for empirical purposes, the ethnolinguistic fragmentation isready available for regression exercises. Nevertheless the adequacy of asynthetic index of hetergeneity depends on the intrinsic characteristicsof the heterogeneous dimension to be measured. In the case of ethnicdiversity there is a very strong conflictive dimension. For this reasonwe argue that the measure of heterogeneity should be one of the class ofpolarization measures. In fact the intuition of the relationship betweenconflict and fractionalization do not hold for more than two groups. Incontrast with the usual problem of polarization indices, which are ofdifficult empirical implementation without making some arbitrary choiceof parameters, we show that the RQ index, proposed by Reynal-Querol (2002),is the only discrete polarization measure that satisfies the basic propertiesof polarization. Additionally we present a derivation of the RQ index froma simple rent seeking model. In the empirical section we show that whileethnic polarization has a positive effect on civil wars and, indirectly ongrowth, this effect is not present when we use ethnic fractionalization.
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In the last 50 years, concern about the loss of lichen diversity associated with forest management and forest fragmentation has led to many studies designed to assess patterns and monitor trends of lichen biodiversity in forests worldwide. However there are surprisingly few studies focusing on the effect of natural disturbance for epiphytic lichens in forest ecosystems and, especially, on how these changes affect the relationships between epiphytic lichens and other organisms. The major goal of this thesis was to characterize and valuate the epiphytic lichens in the Baixo Tamega region (northern Portugal) and to assess its vulnerability to several drivers of change, particularly fire. The study area is located in Aboboreira and Castelo, a mountain area with 105 km2 and a top altitude of approximately 1000 m.a.s.l. In this region, fire is one of the worst natural catastrophes not only because of its high frequency and wide extension but also because of their enormous destructive effects. This thesis has included three case studies that proved the need to develop management and conservation actions for the area. In the first study we assessed the epiphytic lichen diversity in the oak woods of the Aboboreira and Castelo mountains. Results have revealed high diversity value and presence of a lichen community that has suffered general decline throughout Europe. The second study has addressed the impact of fire over epiphytic lichens and community recovering patterns. Results observed along the fire gradient showed that the most common and abundant lichen species establish themselves early in post-fire gradient while old-growth associated lichens tend to recover slowly along the same gradient. The third study intended to evaluate the potential use of selected lichen species or groups as biodiversity surrogates, in a scenario of fire-controlled ecological changes. Results showed that the use of epiphytic lichens as surrogates of bryophyte and vascular plant diversity should consider not only species richeness and composition, but also occurrence of disturbing factors, such fire. among the studied groups, lichen genera is the only group that can be used as surrogate of total epiphytic lichen diversity, independently of fire induced changes
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O principal objectivo desta dissertao expor a problemtica das reas residenciais clandestinas na cidade da Praia. Este processo de produo do espao urbano acompanhou o desenvolvimento da urbe, em resultado das razes sociais, econmicas, polticas e institucionais tendo consequncias urbansticas e sociais graves. Surge porque as diferentes estruturas no souberam ou no foram capazes de dar resposta aos anseios da populao em matria de habitao e solo para construo. Este estudo apresenta um conjunto de informao acerca da realidade das reas residenciais clandestinas que visa dar a dimenso da problemtica na cidade da Praia, seguido de uma anlise mais detalhada de duas reas residenciais. A caracterizao scio-econmica e a anlise do processo construtivo permitiram produzir conhecimentos mais profundos sobre estes fragmentos do tecido urbano. Na dissertao procurmos articular a questo do planeamento com a habitao e as reas residenciais clandestinas atravs da anlise dos diferentes planos propostos ou aplicados na urbe. Procurmos perceber como os planos abordaram esta problemtica e as solues apresentadas para a sua superao. Da mesma forma, a apreciao feita em relao habitao e poltica de solos atravs das resolues legais propostas para contornar a situao urbanstica da cidade. Para uma melhor compreenso do tema discutimos a sua abrangncia terica na perspectiva de diferentes autores e efectuamos o entrosamento entre a componente emprica da produo do espao urbano com a reflexo terica. Perante a fragmentao da urbe em ncleos planeados e espontneos, partimos na auscultao do poder local para a problemtica. A interveno deste em reverter o actual panorama e a poltica preconizada em relao a reconverso das reas residenciais clandestinas visando a sua integrao no quadro do ordenamento da aglomerao
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Human exploitation of the forest in the northwest of So Paulo State has generated enormous fragmentation of that forest. Such disturbance has reduced the populations of insects in general. This work was a survey of social wasps (Hymenoptera, Vespidae; Polistinae) in three areas in different stages of regeneration: Paulo de Faria - SP (435 ha), Pindorama - SP (128 ha) and Neves Paulista - SP (1 ha). These three areas were chosen for comparative purposes. To capture the wasps, it was used: active collecting with attractant liquid (solution of water, salt and sugar) with the aid of a dorsal spray bag. During the period from July to December 2006, 414 social wasps were collected in Paulo de Faria, constituting seven species belonging to four genera; 111 social wasps were collected in Pindorama, constituting six species belonging to four genera, and 129 social wasps were collected in Neves Paulista constituting 12 species belonging to seven genera. In order to compare these three areas ecological indexes were calculated. Neves Paulista had the greatest diversity, and Paulo de Faria presented greater abundance. These factors were probably caused by neighboring areas and ecological corridors, which were limited in Paulo de Faria and Pindorama.
