168 research outputs found
Les alhazai de Maradi (Niger) : histoire d'un groupe de riches marchands sahéliens
Prestigieuse capitale d'une chefferie haoussa au 19ème siècle, Maradi devient pendant la période coloniale un centre de traite dont l'activité repose sur la collecte de l'arachide produite par son arrière-pays et sur la diffusion, en brousse, de marchandises d'origine européenne. Au lendemain de l'indépendance du Niger, sa croissance s'accélère grâce à l'intensification du commerce arachidier puis au développement des échanges avec le Nigéria. Ces transactions, souvent doublées d'opérations frauduleuses tant la frontière est perméable, permettent à la ville de jouir d'une certaine prospérité. Sa rapide évolution (9000 habitants en 1954, près de 100 000 en 1986) a entraîné des mutations sociales et donné naissance à un groupe de riches marchands : les Alhazai (sing. Alhaji). Les Alhazai apparaissent comme une nouvelle génération d'hommes imprégnés à la fois des valeurs de l'Islam et de celles du capitalisme marchand. Ce livre retrace l'histoire de Maradi et l'ascension de ses Alhazai :quand et comment sont-ils parvenus à s'enrichir et à constituer un groupe privilégié au sein de la société locale? Sur quoi porte leur activité? Est-elle seulement motivée par le profit? Quelles sont leurs relations avec les autres acteurs économiques et sociaux
Développement touristique et reproduction sociale à l’île Maurice
Après avoir rappelé le contexte historique et sociologique mauricien, l’article décrit les grandes phases du développement touristique de l’île Maurice en montrant qu’il a permis aux grandes familles franco-mauriciennes de maintenir leur contrôle sur l’économie insulaire, et de pallier les défaillances de l’industrie sucrière qui fit leur fortune. Désormais, le tourisme est devenu un élément important de la reproduction sociale locale en confortant le maintien des hiérarchies et par là des inégalités qui prévalaient dans l’économie de plantation dont il prend la relève. Toutefois, une meilleure répartition de ses retombées semble aujourd’hui nécessaire pour préserver la paix sociale et la stabilité politique du pays, l’une et l’autre conditionnant son avenir.After a presentation of the historical and sociological Mauritian contexts, this article first recalls the main steps of the development of Mauritian tourism. The text then shows how the touristic development of Mauritius has reinforced the economic power of the great franco-mauritian families. Tourism plays nowadays a major role in the social reproduction of Mauritius and in the perpetuation of social and economical inequalities that were already prevailing in the former plantation economy, when the main economic resource of the island was sugar. Finally, a better repartition of the economic benefits of tourism seems today to be necessary in order to preserve the national political stability, and social peace, which are both absolutely necessary for local society’s future
Mapping of transrectal ultrasonographic prostate biopsies: quality control and learning curve assessment by image processing
Objective: Mapping of transrectal ultrasonographic (TRUS) prostate biopsies
is of fundamental importance for either diagnostic purposes or the management
and treatment of prostate cancer, but the localization of the cores seems
inaccurate. Our objective was to evaluate the capacities of an operator to plan
transrectal prostate biopsies under 2-dimensional TRUS guidance using a
registration algorithm to represent the localization of biopsies in a reference
3-dimensional ultrasonographic volume.
Methods: Thirty-two patients underwent a series of 12 prostate biopsies under
local anesthesia performed by 1 operator using a TRUS probe combined with
specific third-party software to verify that the biopsies were indeed conducted
within the planned targets. RESULTS: The operator reached 71% of the planned
targets with substantial variability that depended on their localization (100%
success rate for targets in the middle and right parasagittal parts versus 53%
for targets in the left lateral base). Feedback from this system after each
series of biopsies enabled the operator to significantly improve his dexterity
over the course of time (first 16 patients: median score, 7 of 10 and cumulated
median biopsy length in targets of 90 mm; last 16 patients, median score, 9 of
10 and a cumulated median length of 121 mm; P = .046).
Conclusions: In addition to being a useful tool to improve the distribution
of prostate biopsies, the potential of this system is above all the preparation
of a detailed "map" of each patient showing biopsy zones without substantial
changes in routine clinical practices
The Maunakea Spectroscopic Explorer Book 2018
(Abridged) This is the Maunakea Spectroscopic Explorer 2018 book. It is
intended as a concise reference guide to all aspects of the scientific and
technical design of MSE, for the international astronomy and engineering
communities, and related agencies. The current version is a status report of
MSE's science goals and their practical implementation, following the System
Conceptual Design Review, held in January 2018. MSE is a planned 10-m class,
wide-field, optical and near-infrared facility, designed to enable
transformative science, while filling a critical missing gap in the emerging
international network of large-scale astronomical facilities. MSE is completely
dedicated to multi-object spectroscopy of samples of between thousands and
millions of astrophysical objects. It will lead the world in this arena, due to
its unique design capabilities: it will boast a large (11.25 m) aperture and
wide (1.52 sq. degree) field of view; it will have the capabilities to observe
at a wide range of spectral resolutions, from R2500 to R40,000, with massive
multiplexing (4332 spectra per exposure, with all spectral resolutions
available at all times), and an on-target observing efficiency of more than
80%. MSE will unveil the composition and dynamics of the faint Universe and is
designed to excel at precision studies of faint astrophysical phenomena. It
will also provide critical follow-up for multi-wavelength imaging surveys, such
as those of the Large Synoptic Survey Telescope, Gaia, Euclid, the Wide Field
Infrared Survey Telescope, the Square Kilometre Array, and the Next Generation
Very Large Array.Comment: 5 chapters, 160 pages, 107 figure
Deciphering the Structure, Growth and Assembly of Amyloid-Like Fibrils Using High-Speed Atomic Force Microscopy
Formation of fibrillar structures of proteins that deposit into aggregates has been suggested to play a key role in various neurodegenerative diseases. However mechanisms and dynamics of fibrillization remains to be elucidated. We have previously established that lithostathine, a protein overexpressed in the pre-clinical stages of Alzheimer's disease and present in the pathognomonic lesions associated with this disease, form fibrillar aggregates after its N-terminal truncation. In this paper we visualized, using high-speed atomic force microscopy (HS-AFM), growth and assembly of lithostathine protofibrils under physiological conditions with a time resolution of one image/s. Real-time imaging highlighted a very high velocity of elongation. Formation of fibrils via protofibril lateral association and stacking was also monitored revealing a zipper-like mechanism of association. We also demonstrate that, like other amyloid ß peptides, two lithostathine protofibrils can associate to form helical fibrils. Another striking finding is the propensity of the end of a growing protofibril or fibril to associate with the edge of a second fibril, forming false branching point. Taken together this study provides new clues about fibrillization mechanism of amyloid proteins
Sex differences in circulating proteins in heart failure with preserved ejection fraction
Background
Many patients with heart failure with preserved ejection fraction (HFpEF) are women. Exploring mechanisms underlying the sex differences may improve our understanding of the pathophysiology of HFpEF. Studies focusing on sex differences in circulating proteins in HFpEF patients are scarce.
Methods
A total of 415 proteins were analyzed in 392 HFpEF patients included in The Metabolic Road to Diastolic Heart Failure: Diastolic Heart Failure study (MEDIA-DHF). Sex differences in these proteins were assessed using adjusted logistic regression analyses. The associations between candidate proteins and cardiovascular (CV) death or CV hospitalization (with sex interaction) were assessed using Cox regression models.
Results
We found 9 proteins to be differentially expressed between female and male patients. Women expressed more LPL and PLIN1, which are markers of lipid metabolism; more LHB, IGFBP3, and IL1RL2 as markers of transcriptional regulation; and more Ep-CAM as marker of hemostasis. Women expressed less MMP-3, which is a marker associated with extracellular matrix organization; less NRP1, which is associated with developmental processes; and less ACE2, which is related to metabolism. Sex was not associated with the study outcomes (adj. HR 1.48, 95% CI 0.83–2.63), p = 0.18.
Conclusion
In chronic HFpEF, assessing sex differences in a wide range of circulating proteins led to the identification of 9 proteins that were differentially expressed between female and male patients. These findings may help further investigations into potential pathophysiological processes contributing to HFpEF
The SIB Swiss Institute of Bioinformatics' resources: focus on curated databases
The SIB Swiss Institute of Bioinformatics (www.isb-sib.ch) provides world-class bioinformatics databases, software tools, services and training to the international life science community in academia and industry. These solutions allow life scientists to turn the exponentially growing amount of data into knowledge. Here, we provide an overview of SIB's resources and competence areas, with a strong focus on curated databases and SIB's most popular and widely used resources. In particular, SIB's Bioinformatics resource portal ExPASy features over 150 resources, including UniProtKB/Swiss-Prot, ENZYME, PROSITE, neXtProt, STRING, UniCarbKB, SugarBindDB, SwissRegulon, EPD, arrayMap, Bgee, SWISS-MODEL Repository, OMA, OrthoDB and other databases, which are briefly described in this article
Réseaux, urbanisation et conflits au Sahara
Depuis quelques décennies, on assiste à un renouveau des flux marchands entre les deux versants du Sahara qui engendre d’importantes mutations économiques, sociales et spatiales. De désert inanimé durant la période coloniale, le Sahara est redevenu une zone de transit, les circulations marchandes et migratoires contribuant à son urbanisation. Ces mouvements sont perturbés par des querelles frontalières interétatiques et des conflits identitaires (rébellions touarègues au Mali et au Niger). Les richesses pétrolières et minières du Sahara qui demeurent très convoitées par les grandes puissances de la planète fragilisent également ces flux qui peuvent de ce fait être remis en cause à tout moment.For some decades, we have seen a renewal of commercial flow between the two flanks of the Sahara which experience important social economic and cultural changes. From an inanimate desert during the colonial period, the Sahara has again become a transit zone with merchant traffic and migrations contributing to its urbanization. These movements are somewhat disturbed by interstate border quarrels and identity conflicts (Touareg rebellions in Mali and Niger).The petrol riches and the mining industry are very coveted by the great powers of the planet making this flow more fragile which can be questioned at any moment.Desde hace varios decenios, asistimos a un rebrote de flujos de comerciantes entre las dos vertientes del Sahara que engendra importantes mutaciones económicas, sociales y espaciales. Del desierto inanimado durante el periodo colonial, el Sahara ha vuelto a ser una zona de tránsito, ya que las circulaciones mercantiles y migratorias contribuyen a su urbanización. Estos movimientos se encuentran perturbados por camorras fronterizas entre estados y conflictos de identidad (revueltas de los Tuareg en Malí y Níger). Las riquezas petrolíferas y mineras del Sahara siguen muy codiciadas por las grandes potencias del planeta y debilitan también esos flujos que se pueden, por ello, cuestionar en todo momento.هناك تجدد للدفق التجاري، مند بعض العشريات، بين المنحدريين الإثنيين للصحراء الذي تنجر عنه تحولات اقتصادية، اجتماعية و مجالية جد هامة. و من صحراء خاملة أثناء الفترة الاستعمارية، أصبحت الصحراء من جديد منطقة عبور، بفضل الحركة التجارية و الهجرات التي ساهمت في تحضرها. و تعرف هذه الحركات اضطرابا بسبب بعض الخلافات الحدودية يبن الدول و الصراعات الهوياتية (المتمردين الطوارق في المالي و النيجر). إن الثروات البترولية و المنجمية للصحراء و التي تسعى القوى العظمى في العالم إلى السيطرة عليها، تزيد من هشاشة هذه التدفقات التي يمكن ,استنادا على هذا المنطلق, التشكيك فيها و في أي وقت
L'émergence des créoles portugais du golfe de Guinée
Nous défendons, dans ce travail, l'idée que la question de la genèse des langues créoles doit être envisagée dans une perspective rationnelle. Dans une première partie, nous présentons les données historiques et sociales qui ont suscité puis accompagné la création de la société créole et génère la créolisation linguistique à São Tomé et Príncipe. Dans une seconde partie, nous abordons quelques problèmes de phonologie dans les créoles du golfe de Guinée. Nous considérons que la théorie des contraintes et réparations est une théorie compatible avec l'étude des créoles et proposons des solutions nouvelles à des problèmes de palatalisation et d'analyse suprasegmentale. Dans une troisième partie, nous traitons les problèmes de syntaxe dans le cadre de la grammaire d'arbres adjoints et apportons des solutions syntaxiques et pragmatiques aux questions de la négation, des verbes sériels, des marqueurs de temps, mode et aspect ainsi qu'une nouvelle description des articles définis et indéfinis. Enfin, nous concluons que la genèse des langues créoles peut être mieux cernée grâce à une recherche comparatiste reposant sur des descriptions syntaxiques et pragmatiques lexicalistes. Nous publions en annexe des listes lexicales et des textes créoles divers.This dissertation aims at investigating the roots of the Portuguese-based creole languages of São Tomé and Príncipe. Firstly, I use the TCRS-Loanword Model, offering new solutions to some phonological problems. Secondly, I investigate syntactical problems - TMA markers, serial verbs and negative particle - via a Tree Adjoining Grammar analysis combined with Relevance theory. I then show that my approach provides encouraging results, particularly with regard to relexification.NANCY2-BU Lettres (543952103) / SudocSudocFranceF
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