Revêtement galoisien de l’algèbre d’extension par relations partielle et sa catégorie de modules

Dans le but de décrire une classe d’algèbres qui, comme les algèbres inclinées amassées, admettent des tranches locales dans leur catégorie de modules, Assem, Bustamante, Dionne, LeMeur et Smith ont introduit l’algèbre B d’extension par relations partielle. Le but de ce mémoire est de définir une algèbre qu’on appelle répétitive d’extension par relations partielle et un foncteur qui est un revêtement de Galois, puis d’étudier le lien entre les catégories de modules associés

An insight into the sialotranscriptome of the West Nile mosquito vector, <it>Culex tarsalis</it>

<p>Abstract</p> <p>Background</p> <p>Saliva of adult female mosquitoes help sugar and blood feeding by providing enzymes and polypeptides that help sugar digestion, control microbial growth and counteract their vertebrate host hemostasis and inflammation. Mosquito saliva also potentiates the transmission of vector borne pathogens, including arboviruses. <it>Culex tarsalis </it>is a bird feeding mosquito vector of West Nile Virus closely related to <it>C. quinquefasciatus</it>, a mosquito relatively recently adapted to feed on humans, and the only mosquito of the genus <it>Culex </it>to have its sialotranscriptome so far described.</p> <p>Results</p> <p>A total of 1,753 clones randomly selected from an adult female <it>C. tarsalis </it>salivary glands (SG) cDNA library were sequenced and used to assemble a database that yielded 809 clusters of related sequences, 675 of which were singletons. Primer extension experiments were performed in selected clones to further extend sequence coverage, allowing for the identification of 283 protein sequences, 80 of which code for putative secreted proteins.</p> <p>Conclusion</p> <p>Comparison of the <it>C. tarsalis </it>sialotranscriptome with that of <it>C. quinquefasciatus </it>reveals accelerated evolution of salivary proteins as compared to housekeeping proteins. The average amino acid identity among salivary proteins is 70.1%, while that for housekeeping proteins is 91.2% (P < 0.05), and the codon volatility of secreted proteins is significantly higher than those of housekeeping proteins. Several protein families previously found exclusive of mosquitoes, including only in the <it>Aedes </it>genus have been identified in <it>C. tarsalis</it>. Interestingly, a protein family so far unique to <it>C. quinquefasciatus</it>, with 30 genes, is also found in <it>C. tarsalis</it>, indicating it was not a specific <it>C. quinquefasciatus </it>acquisition in its evolution to optimize mammal blood feeding.</p

Expression of Interest: The Atmospheric Neutrino Neutron Interaction Experiment (ANNIE)

Submitted for the January 2014 Fermilab Physics Advisory Committee meetingSubmitted for the January 2014 Fermilab Physics Advisory Committee meetingSubmitted for the January 2014 Fermilab Physics Advisory Committee meetingSubmitted for the January 2014 Fermilab Physics Advisory Committee meetingNeutron tagging in Gadolinium-doped water may play a significant role in reducing backgrounds from atmospheric neutrinos in next generation proton-decay searches using megaton-scale Water Cherenkov detectors. Similar techniques might also be useful in the detection of supernova neutrinos. Accurate determination of neutron tagging efficiencies will require a detailed understanding of the number of neutrons produced by neutrino interactions in water as a function of momentum transferred. We propose the Atmospheric Neutrino Neutron Interaction Experiment (ANNIE), designed to measure the neutron yield of atmospheric neutrino interactions in gadolinium-doped water. An innovative aspect of the ANNIE design is the use of precision timing to localize interaction vertices in the small fiducial volume of the detector. We propose to achieve this by using early production of LAPPDs (Large Area Picosecond Photodetectors). This experiment will be a first application of these devices demonstrating their feasibility for Water Cherenkov neutrino detectors

Bone growth during rapamycin therapy in young rats

<p>Abstract</p> <p>Background</p> <p>Rapamycin is an effective immunosuppressant widely used to maintain the renal allograft in pediatric patients. Linear growth may be adversely affected in young children since rapamycin has potent anti-proliferative and anti-angiogenic properties.</p> <p>Methods</p> <p>Weanling three week old rats were given rapamycin at 2.5 mg/kg daily by gavage for 2 or 4 weeks and compared to a Control group given equivalent amount of saline. Morphometric measurements and biochemical determinations for serum calcium, phosphate, iPTH, urea nitrogen, creatinine and insulin-growth factor I (IGF-I) were obtained. Histomorphometric analysis of the growth plate cartilage, in-situ hybridization experiments and immunohistochemical studies for various proteins were performed to evaluate for chondrocyte proliferation, chondrocyte differentiation and chondro/osteoclastic resorption.</p> <p>Results</p> <p>At the end of the 2 weeks, body and tibia length measurements were shorter after rapamycin therapy associated with an enlargement of the hypertrophic zone in the growth plate cartilage. There was a decrease in chondrocyte proliferation assessed by <it>histone-4 </it>and <it>mammalian target of rapamycin </it>(<it>mTOR</it>) expression. A reduction in <it>parathyroid hormone/parathyroid hormone related peptide (PTH/PTHrP) </it>and an increase in <it>Indian hedgehog </it>(<it>Ihh</it>) expression may explain in part, the increase number of hypertrophic chondrocytes. The number of TRAP positive multinucleated chondro/osteoclasts declined in the chondro-osseous junction with a decrease in the <it>receptor activator of nuclear factor kappa β ligand </it>(<it>RANKL</it>) and <it>vascular endothelial growth factor </it>(<it>VEGF</it>) expression. Although body and tibial length remained short after 4 weeks of rapamycin, changes in the expression of chondrocyte proliferation, chondrocyte differentiation and chondro/osteoclastic resorption which were significant after 2 weeks of rapamycin improved at the end of 4 weeks.</p> <p>Conclusion</p> <p>When given to young rats, 2 weeks of rapamycin significantly decreased endochondral bone growth. No catch-up growth was demonstrated at the end of 4 weeks, although markers of chondrocyte proliferation and differentiation improved. Clinical studies need to be done to evaluate these changes in growing children.</p

Oral tolerance to cancer can be abrogated by T regulatory cell inhibition

Oral administration of tumour cells induces an immune hypo-responsiveness known as oral tolerance. We have previously shown that oral tolerance to a cancer is tumour antigen specific, non-cross-reactive and confers a tumour growth advantage. We investigated the utilisation of regulatory T cell (Treg) depletion on oral tolerance to a cancer and its ability to control tumour growth. Balb/C mice were gavage fed homogenised tumour tissue – JBS fibrosarcoma (to induce oral tolerance to a cancer), or PBS as control. Growth of subcutaneous JBS tumours were measured; splenic tissue excised and flow cytometry used to quantify and compare systemic Tregs and T effector (Teff) cell populations. Prior to and/or following tumour feeding, mice were intraperitoneally administered anti-CD25, to inactivate systemic Tregs, or given isotype antibody as a control. Mice which were orally tolerised prior to subcutaneous tumour induction, displayed significantly higher systemic Treg levels (14% vs 6%) and faster tumour growth rates than controls (p<0.05). Complete regression of tumours were only seen after Treg inactivation and occurred in all groups - this was not inhibited by tumour feeding. The cure rates for Treg inactivation were 60% during tolerisation, 75% during tumour growth and 100% during inactivation for both tolerisation and tumour growth. Depletion of Tregs gave rise to an increased number of Teff cells. Treg depletion post-tolerisation and post-tumour induction led to the complete regression of all tumours on tumour bearing mice. Oral administration of tumour tissue, confers a tumour growth advantage and is accompanied by an increase in systemic Treg levels. The administration of anti-CD25 Ab decreased Treg numbers and caused an increase in Teffs. Most notably Treg cell inhibition overcame established oral tolerance with consequent tumor regression, especially relevant to foregut cancers where oral tolerance is likely to be induced by the shedding of tumour tissue into the gut

Green Production of Anionic Surfactant Obtained from Pea Protein

A pea protein isolate was hydrolyzed by a double enzyme treatment method in order to obtain short peptide sequences used as raw materials to produce lipopeptides-based surfactants. Pea protein hydrolysates were prepared using the combination of Alcalase and Flavourzyme. The influence of the process variables was studied to optimize the proteolytic degradation to high degrees of hydrolysis. The average peptide chain lengths were obtained at 3–5 amino acid units after a hydrolysis of 30 min with the mixture of enzymes. Then, N-acylation in water, in presence of acid chloride (C12 and C16), carried out with a conversion rate of amine functions of 90%, allowed to obtain anionic surfactant mixtures (lipopeptides and sodium fatty acids). These two steps were performed in water, in continuous and did not generate any waste. This process was therefore in line with green chemistry principles. The surface activities (CMC, foaming and emulsifying properties) of these mixtures were also studied. These formulations obtained from natural renewable resources and the reactions done under environmental respect, could replace petrochemical based surfactants for some applications