42 research outputs found

    Synthesis of an Optimal Dynamic Regulator Based on Linear Quadratic Gaussian (LQG) for the Control of the Relative Humidity under Experimental Greenhouse

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    This paper describes one practical approach that suggests a model based technique to control in real time the relative humidity under greenhouse. The humidity level is one of the most difficult environmental factors to be regulated in greenhouse. Moreover, maintaining and correcting for more or less humidity can be a challenge for even the most sophisticated monitoring and control equipment. For these raisons, a Linear Quadratic Gaussian (LQG) controller for relative humidity regulation under greenhouse turns out to be useful. Indeed a LQG controller is proposed for a relative humidity under a greenhouse control task. So, the state space model, which is best fitting the acquired data, was identified using the Numerical Subspace State Space System IDentification (N4SID) algorithm. The mathematical model that is obtained will be used for evaluating the parameters of LQG strategy. The proposed controller is implemented in two steps, in one hand, Kalman filter (KF) is used to develop an observer that estimates the state of relative humidity under greenhouse. In the other hand, the state feedback controller gain is estimated using a linear quadratic criterion function. The suggested optimal implemented controller using Matlab/Simulink environment is applied to an experimental greenhouse. We found, according to the results, that the controller is able to lead the inside relative humidity to the desired value with high accuracy, regardless of the external disturbances

    Anévrisme de l’artère splénique rompu dans l’estomac: traitement chirurgical après échec d’une tentative d’embolisation

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    L'anévrisme de l'artère splénique (AAS) est une entité pathologique rare le plus souvent asymptomatique. Nous rapportons le cas d'un patient âgéde 60 ans, hypertendu qui s'est présenté aux urgences pour un épisode d'hématémèse sans retentissement hémodynamique. Un bilan completcomportant un Angioscanner abdominal a mis en évidence un anévrisme de l'artère splénique refoulant la paroi postérieure de l'estomac en avant.Le diagnostic d'anévrisme de l'artère splénique rompu dans l'estomac a été posé et un traitement endovasculaire à type d'embolisation par coilseffectué. Au 5ème jour post embolisation, le patient nous a été référé pour une persistance de mélénas. Un traitement chirurgical a été décidé. Lamise à plat de l'anévrisme a permis d'évacuer les coils et le thrombus. L'objectif de cette observation est de montrer que l'embolisation d'un AASrompu dans l'estomac a été une cause de retard thérapeutique qui pourrait être fatal pour le patient. Le traitement de référence est la cure chirurgicale de l'AAS par voie conventionnelle sans rétablissement de la continuité  artérielle splénique, sans splénectomie et avec suture de l'orifice digestif

    Evaluating the textural and mechanical properties of an Mg-Dy alloy processed by high-pressure torsion

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    Samples of an Mg-0.41Dy (wt. %) alloy were severely deformed by high-pressure torsion (HPT) at room temperature up to 15 turns and the texture, microstructure and microhardness values in the centres, mid-radial points and edges of the HPT-deformed discs were investigated using X-ray diffraction, Electron BackScatter Diffraction and Vickers microhardness measurements. The textures in the centres of discs were characterized by a typical weak basal fiber whereas at both the mid-points and edges of the discs there was a strong basal texture where the c-axis of most grains was shifted 15° away from the shear direction. An almost homogeneous ultrafine-grained structure with a grain size of about 0.75 μm was achieved after 15 HPT turns. The microhardness values in these three positions increased with increasing numbers of turns, reached a maximum and then decreased to a lower steady-state level at large strains. In addition to dislocation and grain size hardening, the results show that texture strengthening contributes significantly to the rapid increase in hardening in the early stages of deformation

    An autosomal recessive leucoencephalopathy with ischemic stroke, dysmorphic syndrome and retinitis pigmentosa maps to chromosome 17q24.2-25.3

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    Background Single-gene disorders related to ischemic stroke seem to be an important cause of stroke in young patients without known risk factors. To identify new genes responsible of such diseases, we studied a consanguineous Moroccan family with three affected individuals displaying hereditary leucoencephalopathy with ischemic stroke, dysmorphic syndrome and retinitis pigmentosa that appears to segregate in autosomal recessive pattern. Methods All family members underwent neurological and radiological examinations. A genome wide search was conducted in this family using the ABI PRISM linkage mapping set version 2.5 from Applied Biosystems. Six candidate genes within the region linked to the disease were screened for mutations by direct sequencing. Results Evidence of linkage was obtained on chromosome 17q24.2-25.3. Analysis of recombination events and LOD score calculation suggests linkage of the responsible gene in a genetic interval of 11 Mb located between D17S789 and D17S1806 with a maximal multipoint LOD score of 2.90. Sequencing of seven candidate genes in this locus, ATP5H, FDXR, SLC25A19, MCT8, CYGB, KCNJ16 and GRIN2C, identified three missense mutations in the FDXR gene which were also found in a homozygous state in three healthy controls, suggesting that these variants are not disease-causing mutations in the family. Conclusion A novel locus for leucoencephalopathy with ischemic stroke, dysmorphic syndrome and retinitis pigmentosa has been mapped to chromosome 17q24.2-25.3 in a consanguineous Moroccan family

    SEPT4, a p53 target gene product, implicates p 53 in the regulation of exocytosis

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    Résumé : Le cancer, qui est responsable d'un quart des décès en Suisse, exhibe un état cellulaire désordonné, qui lui-même, est la conséquence d'un dérèglement des gènes. Le gène le plus fréquemment altéré, dans les cas de cancers humains, est p53. Ce gène encode un facteur de transcription, impliqué dans la régulation de nombreux gènes impliqués dans le cycle cellulaire, l'apoptose ou la différenciation. Notre laboratoire a récemment identifié seize nouveaux gènes, dont l'expression est régulée par p53, parmi lesquels sept4, su jet de cette thèse. La protéine 5EPT4 appartient à la famille des septines, qui est impliquée dans la cytokinèse. Dans ce travail, nous avons confirmé la régulation de l'expression de sept4 par p53 dans des tissus de souris, et étonnamment, seul un des deux promoteurs du gène sept4 est contrôlé par p53. En outre, l'approche immunohistologique nous a permis de supposer une implication de la protéine SEPT4 dans le mécanisme de l'exocytose. Cette hypothèse a été confirmée par l'interaction de SEPT4 avec la protéine syntaxine 1A, et par son activité inhibitrice sur la sécrétion stimulée. En élargissant l'étude de la protéine SEPT4, nous avons découvert que celle-ci avait comme partenaire fonctionnel, la protéine Pinl, une enzyme qui catalyse l'isomérisation cis-trans du lien peptidique précédant une proline. bans ce contexte, nous avons démontré que l'interaction entre ces deux protéines reposait sur le domaine WW de Pinl, un type de domaine reconnaissant les motifs phosphoséryl-prolyl et phosphothréonyl-prolyl. Ce dernier résultat nous a conduit à examiner la phosphorylation de 5EPT4. Nous avons démontré que la partie N-terminale de SEPT4 était phosphorylée par la kinase Cdk5. La co¬expression de Cdk5 et de SEPT4 stimule la dégradation de SEPT4, indépendamment de la voie du protéasome. Ainsi, l'ensemble de nos observations fournissent l'évidence de l'engagement de la protéine SEPT4 dans la régulation de l'exocytose, et soutiennent le rôle de p53 dans le contrôle de l'exocytose, via SEPT4, ce qui constituerait un nouveau rôle fonctionnel pour ce gardien du génome. Summary: Cancer, which is responsible for a quarter of the deaths in Switzerland, exhibits a disordered cellular state, which itself, is the consequence of an altered state of genes. The most frequently altered gene in human cancer is p53. This gene encodes a transcription factor, implicated in the regulation of numerous genes involved in cell cycle, apoptosis or differentiation. Our laboratory has recently identified sixteen new genes whose expression is regulated by p53, amongst them septin 4, which is the subject of this thesis. The SEPT4 protein belongs to the septin family which is implicated in cytokinesis. In the present work, we have confirmed the regulation of sept4 expression by p53 in mouse tissues, and surprisingly, only one of the two sept4 promoters is regulated by p53. In addition, the immunohistologic approach enabled us to suppose a role of SEPT4 in exocytosis. This assumption was confirmed by the interaction of SEPT4 with syntaxin 1A, and by its inhibiting activity on stimulated secretion. By widening the analysis of SEPT4, we identified Pin1 as an interacting protein. Pin1 is an enzyme which catalyzes the cis-trans isomerization of the peptide bond preceding a proline residue. In this context, we showed that the interaction between these two proteins depends on the WW domain of Pin 1. This domain has been shown to function as a phosphoserine- or phosphothreonine¬binding module. This last result prompted us to examine phosphorylation of SEPT4. We demonstrated that the N-terminal portion of SEPT4 was phosphorylated by the Cdk5 kinase. The co-expression of Cdk5 with 5EPT4 stimulates SEPT4 degradation, independently of the proteasome pathway. Thus, these observations provide evidence for the engagement of SEPT4 in the regulation of exocytosis, and supports the role of p53 in the control of exocytosis, via SEPT4, which constitutes a new functional role for this guardian of the genome

    Vite: idrolizzati proteici contro lo stress idrico.

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    Le prove sono state condotte dal 2011 al 2014 in Valpolicella (provincia di Verona) su terreni fortemente calcarei e ciottolosi. \uc8 stato impiegato il vitigno Corvina allevato a spalliera e con potatura a Guyot. Gli idrolizzati proteici utilizzati erano di origine vegetale (tesi B, tesi C, tesi B + C) e le dosi distribuite per via fogliare sono state di 2 kg/ha (tesi B) e 0,5 kg/ha (tesi C). Le dosi sono state mantenute anche per la miscela dei due prodotti (tesi B + C). Nel 2014 sono stati eseguiti tre trattamenti a partire dalla pre-fioritura (BBCH 57) e distanziati 10 giorni uno dall\u2019altro. I controlli sullo stato idrico delle piante sono stati effettuati avvalendosi di una termocamera a infrarossi (foto 1, 2 e 3) in base al protocollo indicato dalla letteratura sull\u2019utilizzo dell\u2019apparecchiatura. I trattamenti hanno avuto efficacia sui parametri qualitativi della variet\ue0 Corvina. Infatti \ue8 stato osservato un incremento del grado zuccherino delle tesi trattate rispetto al controllo, in un\u2019annata caratterizzata da una seria difficolt\ue0 dell\u2019uva a raggiungere un grado alcolico potenziale soddisfacente. Le differenze sono risultate statisticamente significative. Un altro parametro influenzato dai trattamenti \ue8 stato il contenuto di polifenoli totali della bacca, che \ue8 variato, in modo statisticamente significativo, da 1.322 mg/L del controllo, a 1.733 mg/L della tesi C, a 1.819 della tesi B e a 2.002 mg/L della tesi B + C. Anche il contenuto di antociani totali \ue8 variato positivamente a seguito dei trattamenti effettuati
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