Modélisation et simulation d'un système électrique hybride à jumelage hydroélectrique-solaire, avec stockage à batteries

L’exploitation simultanée de plusieurs sources d’énergie, lorsque rendue possible, permet de répondre efficacement à de nombreuses attentes des consommateurs électriques. Toutefois, cette perspective apporte de nouveaux défis quant à la stabilité du système résultant, sa fiabilité et sa résilience aux intempéries auxquelles il pourrait être soumis. Par ailleurs, des contraintes additionnelles sont introduites du fait de l’intégration dans ces systèmes, de nombreux équipements d’électronique de puissance et très souvent des dispositifs de stockage ayant des dynamiques variées. Ce mémoire a pour objectif l’étude, la modélisation et la simulation d’un système hybride à énergies hydroélectrique et solaire photovoltaïque avec stockage à batterie électrochimique. L’enjeu de l’étude est d’observer le comportement à différents niveaux de chaque unité de production et du système de stockage, de concevoir des contrôleurs adaptés et de faire une analyse des résultats obtenus. Le logiciel MATLAB/Simulink® est utilisé pour les simulations ; une étude conceptuelle de ces sources d’énergie et du système de stockage employant plus précisément des batteries au Lithium-Ion est réalisée. Une stratégie de contrôle hiérarchique est proposée en accord avec les développements récents dans la littérature sur le sujet ; des contrôleurs linéaires, principalement du type PI et PID sont implémentés afin de réguler la tension, la fréquence et d’autres variables du système dans diverses conditions de fonctionnement

Amyloid and tau pathology associations with personality traits, neuropsychiatric symptoms, and cognitive lifestyle in the preclinical phases of sporadic and autosomal dominant Alzheimer’s disease

Background Major prevention trials for Alzheimer’s disease (AD) are now focusing on multidomain lifestyle interventions. However, the exact combination of behavioral factors related to AD pathology remains unclear. In 2 cohorts of cognitively unimpaired individuals at risk of AD, we examined which combinations of personality traits, neuropsychiatric symptoms, and cognitive lifestyle (years of education or lifetime cognitive activity) related to the pathological hallmarks of AD, amyloid-β, and tau deposits. Methods A total of 115 older adults with a parental or multiple-sibling family history of sporadic AD (PREVENT-AD [PRe-symptomatic EValuation of Experimental or Novel Treatments for AD] cohort) underwent amyloid and tau positron emission tomography and answered several questionnaires related to behavioral attributes. Separately, we studied 117 mutation carriers from the DIAN (Dominant Inherited Alzheimer Network) study group cohort with amyloid positron emission tomography and behavioral data. Using partial least squares analysis, we identified latent variables relating amyloid or tau pathology with combinations of personality traits, neuropsychiatric symptoms, and cognitive lifestyle. Results In PREVENT-AD, lower neuroticism, neuropsychiatric burden, and higher education were associated with less amyloid deposition (p = .014). Lower neuroticism and neuropsychiatric features, along with higher measures of openness and extraversion, were related to less tau deposition (p = .006). In DIAN, lower neuropsychiatric burden and higher education were also associated with less amyloid (p = .005). The combination of these factors accounted for up to 14% of AD pathology. Conclusions In the preclinical phase of both sporadic and autosomal dominant AD, multiple behavioral features were associated with AD pathology. These results may suggest potential pathways by which multidomain interventions might help delay AD onset or progression

Synthèse de nanostructures d’oxyde de ruthénium par plasma micro-ondes en post-décharge à la pression atmosphérique

Various ruthenium dioxide nanostructures were locally grown by the oxidation with an atmospheric pressure Ar-O2 microwave micro-afterglow of bulk ruthenium samples or thin films previously deposited by magnetron sputtering on silicon and silica. A special attention was paid to the distribution of the surface temperature of the sample which evolves typically between 530 K and 900 K. The use of plasma discharges allows a lowering of the temperature compared with the thermal oxidation conditions, given that molecular oxygen is excited or dissociated, which provides more reactive species such as singlet oxygen or atomic oxygen. According to the substrate used and the operating conditions, different nanostructures can be formed: lamellae separated by 20–50 nm, localized nano-sea urchins, high density of long nanowires and microcrystals. Nanostructures obtained were characterized by various techniques (electron microscopy, X-ray diffraction or secondary ion mass spectrometry). The grown RuO2 nanowires were determined to be generally single-crystalline with random crystallographic orientations. Very different growth mechanisms were observed and identified. Although it seems impossible to obtain uniformly distributed nanostructures on bulk ruthenium substrates, it is possible from substrates coated by a thin layer of ruthenium, which allows the formation of nanowire carpet. The possibility to localize the growth of nanowires by adding alkali salts has been studied. However, if the use of NaCl or KCl crystals locally enhances the nanowire density, they do not ensure systematically the growth of nanowiresDiverses nanostructures de dioxyde de ruthénium ont été synthétisées par oxydation locale du ruthénium massif et de films minces de ruthénium au moyen de plasmas micro-ondes Ar-O2 en post-décharge à la pression atmosphérique. Ces revêtements ont été déposés préalablement par pulvérisation magnétron. Une étude approfondie a été réalisée pour déterminer l’évolution radiale de la température de surface qui évolue typiquement entre 530 K et 900 K. L’utilisation d’un plasma permet un abaissement de la température d’oxydation par rapport à des conditions thermiques dans la mesure où l’oxygène moléculaire est excité ou dissocié, ce qui fournit des espèces plus réactives comme l’oxygène singulet ou l’oxygène atomique. Suivant le substrat utilisé et les conditions opératoires, des structures en lamelles distantes de 20-50 nm, des micro-oursins localisés, des nanofils longs et denses et des microcristaux peuvent être formés. Les nanostructures obtenues ont été caractérisées par différentes techniques (microscopies électroniques, diffraction des rayons X ou spectrométrie de masse des ions secondaires). Les analyses MET ne révèlent pas d’orientation privilégiée des nanofils qui sont généralement monocristallins. Des mécanismes de croissance des nanostructures très différents ont été observés et identifiés. S’il apparaît qu’il est impossible sur substrat massif de ruthénium d’obtenir des nanostructures uniformément réparties, il en va autrement avec des substrats recouverts d’une couche mince de ruthénium qui permettent de former de véritables tapis de nanofils. La possibilité de localiser la croissance des nanofils par ajout de sels alcalins a été étudié

Synthesis of ruthenium oxide nanostructures by atmospheric pressure microwaves afterglow

Diverses nanostructures de dioxyde de ruthénium ont été synthétisées par oxydation locale du ruthénium massif et de films minces de ruthénium au moyen de plasmas micro-ondes Ar-O2 en post-décharge à la pression atmosphérique. Ces revêtements ont été déposés préalablement par pulvérisation magnétron. Une étude approfondie a été réalisée pour déterminer l’évolution radiale de la température de surface qui évolue typiquement entre 530 K et 900 K. L’utilisation d’un plasma permet un abaissement de la température d’oxydation par rapport à des conditions thermiques dans la mesure où l’oxygène moléculaire est excité ou dissocié, ce qui fournit des espèces plus réactives comme l’oxygène singulet ou l’oxygène atomique. Suivant le substrat utilisé et les conditions opératoires, des structures en lamelles distantes de 20-50 nm, des micro-oursins localisés, des nanofils longs et denses et des microcristaux peuvent être formés. Les nanostructures obtenues ont été caractérisées par différentes techniques (microscopies électroniques, diffraction des rayons X ou spectrométrie de masse des ions secondaires). Les analyses MET ne révèlent pas d’orientation privilégiée des nanofils qui sont généralement monocristallins. Des mécanismes de croissance des nanostructures très différents ont été observés et identifiés. S’il apparaît qu’il est impossible sur substrat massif de ruthénium d’obtenir des nanostructures uniformément réparties, il en va autrement avec des substrats recouverts d’une couche mince de ruthénium qui permettent de former de véritables tapis de nanofils. La possibilité de localiser la croissance des nanofils par ajout de sels alcalins a été étudiéeVarious ruthenium dioxide nanostructures were locally grown by the oxidation with an atmospheric pressure Ar-O2 microwave micro-afterglow of bulk ruthenium samples or thin films previously deposited by magnetron sputtering on silicon and silica. A special attention was paid to the distribution of the surface temperature of the sample which evolves typically between 530 K and 900 K. The use of plasma discharges allows a lowering of the temperature compared with the thermal oxidation conditions, given that molecular oxygen is excited or dissociated, which provides more reactive species such as singlet oxygen or atomic oxygen. According to the substrate used and the operating conditions, different nanostructures can be formed: lamellae separated by 20–50 nm, localized nano-sea urchins, high density of long nanowires and microcrystals. Nanostructures obtained were characterized by various techniques (electron microscopy, X-ray diffraction or secondary ion mass spectrometry). The grown RuO2 nanowires were determined to be generally single-crystalline with random crystallographic orientations. Very different growth mechanisms were observed and identified. Although it seems impossible to obtain uniformly distributed nanostructures on bulk ruthenium substrates, it is possible from substrates coated by a thin layer of ruthenium, which allows the formation of nanowire carpet. The possibility to localize the growth of nanowires by adding alkali salts has been studied. However, if the use of NaCl or KCl crystals locally enhances the nanowire density, they do not ensure systematically the growth of nanowire

High-affinity RNA Aptamers Against the HIV-1 Protease Inhibit Both In Vitro Protease Activity and Late Events of Viral Replication

HIV-1 aspartyl protease (PR) plays a key role in virion morphogenesis, underscoring the effectiveness of protease inhibitors (PI). Despite their utility, side effects and drug-resistance remains a problem. We report the development of RNA aptamers as inhibitors of HIV-1 PR for potential use in anti-HIV gene therapy. Employing Systematic Evolution of Ligands by Exponential Enrichment (SELEX), we isolated four unique families of anti-HIV-1 PR RNA aptamers displaying moderate binding affinities (Kd = 92–140 nmol/l) and anti-PR inhibitory activity (Kis = 138–647 nmol/l). Second-generation RNA aptamers selected from partially randomized pools based on two of the aptamer sequences displayed striking enhancements in binding (Kds = 2–22 nmol/l) and inhibition (Kis = 31–49 nmol/l). The aptamers were specific in that they did not bind either the related HIV-2 protease, or the cellular aspartyl protease, Cathepsin D. Site-directed mutagenesis of a second-generation aptamer to probe the predicted secondary structure indicated that the stem-loops SL2 and SL3 and the stem P1 were essential for binding and that only the 3’-most 17 nucleotides were dispensable. Anti-PR aptamers inhibited HIV replication in vitro and the degree of inhibition was higher for second-generation aptamers with greater affinity and the inhibition was abrogated for a nonbinding aptamer variant

Software efical para la gestión eficiente de motores en la industria; Software Efical for Efficient Management of Motors in the Industry

<p>En este trabajo se explica el dise&ntilde;o, e implementaci&oacute;n de una herramienta capaz de controlar y gestionar<br />eficientemente los motores el&eacute;ctricos de una industria. Para ello se elabor&oacute; un software de f&aacute;cil manejo<br />que resolviera el problema y que adem&aacute;s brindara otras opciones a los usuarios que hicieran uso del<br />mismo. EFICAL&reg;, controla el inventario de los motores y sus equipos accionados, sus par&aacute;metros<br />nominales, mantenimientos y ensayos, permite calcular la eficiencia por distintos m&eacute;todos y brinda adem&aacute;s<br />datos de cat&aacute;logos de diversos fabricantes.</p><p>&nbsp;</p><p>&nbsp;</p><p>This work explains the developing and application of a software tool for efficient management of electric<br />motors in the industry. For this it was develop friendly software that solve the problem and more over gives<br />another option to users. EFICAL&reg;, controls the motor inventory and the equipment that they drive, their<br />nominal parameters, maintenance, and testing; also allow the efficiency calculations by various methods<br />and gives the catalog data of some manufacturers.</p

RNA Aptamers Directed to Human Immunodeficiency Virus Type 1 Gag Polyprotein Bind to the Matrix and Nucleocapsid Domains and Inhibit Virus Production▿ †

Gag orchestrates the assembly and release of human immunodeficiency virus type 1 (HIV-1) particles. We explored here the potential of anti-Gag RNA aptamers to inhibit HIV-1 replication. In vitro, RNA aptamers raised against an HIV-1 Gag protein, lacking the N-terminal myristate and the C-terminal p6 (DP6-Gag), could bind to matrix protein (MA), nucleocapsid protein (NC), or entire DP6-Gag protein. Upon cotransfection with pNL4-3.Luc molecular clone into 293T cells, six of the aptamers caused mild inhibition (2- to 3-fold) in the extracellular capsid levels, and one aptamer displayed 20-fold inhibition. The reduction was not due to a release defect but reflected Gag mRNA levels. We hypothesized that the aptamers influence genomic RNA levels via perturbation of specific Gag-genomic RNA interactions. Binding studies revealed that the “NC-binders” specifically compete with the packaging signal (ψ) of HIV-1 for binding to DP6-Gag. Therefore, we tested the ability of two NC-binders to inhibit viruses containing ψ-region deletions (ΔSL1 or ΔSL3) and found that the NC-binders were no longer able to inhibit Gag synthesis. The inability of these aptamers to inhibit ψ-deleted viruses correlated with the absence of competition with the corresponding ψ transcripts lacking SL1 or SL3 for binding DP6-Gag in vitro. These results indicate that the NC-binding aptamers disrupt Gag-genomic RNA interaction and negatively affect genomic RNA transcription, processing, or stability. Our results reveal an essential interaction between HIV-1 Gag and the ψ-region that may be distinct from that which occurs during the encapsidation of genomic RNA. Thus, anti-Gag aptamers can be an effective tool to perturb Gag-genomic RNA interactions

Subjective Cognitive Decline Is Associated With Altered Default Mode Network Connectivity in Individuals With a Family History of Alzheimer's Disease

Background: Both subjective cognitive decline (SCD) and a family history of Alzheimer's disease (AD) portend risk of brain abnormalities and progression to dementia. Posterior default mode network (pDMN) connectivity is altered early in the course of AD. It is unclear whether SCD predicts similar outcomes in cognitively normal individuals with a family history of AD. Methods: We studied 124 asymptomatic individuals with a family history of AD (age 64 ± 5 years). Participants were categorized as having SCD if they reported that their memory was becoming worse (SCD+). We used extensive neuropsychological assessment to investigate five different cognitive domain performances at baseline (n = 124) and 1 year later (n = 59). We assessed interconnectivity among three a priori defined ROIs: pDMN, anterior ventral DMN, medial temporal memory system (MTMS), and the connectivity of each with the rest of brain. Results: Sixty-eight (55%) participants reported SCD. Baseline cognitive performance was comparable between groups (all false discovery rate-adjusted p values >.05). At follow-up, immediate and delayed memory improved across groups, but the improvement in immediate memory was reduced in SCD+ compared with SCD− (all false discovery rate–adjusted p values <.05). When compared with SCD−, SCD+ subjects showed increased pDMN–MTMS connectivity (false discovery rate–adjusted p <.05). Higher connectivity between the MTMS and the rest of the brain was associated with better baseline immediate memory, attention, and global cognition, whereas higher MTMS and pDMN–MTMS connectivity were associated with lower immediate memory over time (all false discovery rate–adjusted p values <.05). Conclusions: SCD in cognitively normal individuals is associated with diminished immediate memory practice effects and a brain connectivity pattern that mirrors early AD-related connectivity failure

Proximity to parental symptom onset and amyloid-β burden in sporadic Alzheimer disease

IMPORTANCE Alzheimer disease (AD) develops during several decades. Presymptomatic individuals might be the best candidates for clinical trials, but their identification is challenging because they have no symptoms. OBJECTIVE To assess whether a sporadic parental estimated years to symptom onset calculation could be used to identify information about amyloid-β (Aβ) levels in asymptomatic individuals with a parental history of AD dementia. DESIGN, SETTING, AND PARTICIPANTS This cohort study analyzed Aβ1-42 in cerebrospinal fluid (CSF) specimens from 101 cognitively normal individuals who had a lumbar puncture as part of the Presymptomatic Evaluation of Novel or Experimental Treatments for Alzheimer Disease (PREVENT-AD) cohort from September 1, 2011, through November 30, 2016 (374 participants were enrolled in the cohort during this period). The study estimated each participant's proximity to his/her parent's symptom onset by subtracting the index relative's onset age from his/her current age. The association between proximity to parental symptom onset and Aβ levels was then assessed using apolipoprotein E ϵ4 (APOE4) status and sex as interactive terms. These analyses were performed again in 2 independent cohorts using CSF and Pittsburgh compound B carbon 11-labeled positron emission tomography (PIB-PET) Aβ biomarkers: the Adult Children Study (ACS) and the Wisconsin Registry for Alzheimer Prevention (WRAP) cohorts. MAIN OUTCOMES AND MEASURES The association between proximity to parental symptom onset and Aβ burden in asymptomatic individuals with a parental history of sporadic AD. RESULTS The present analysis included a subset of 101 PREVENT-AD individuals (mean [SD] age, 61.8 [5.1] years; 30 [29.7%] male), 128 ACS participants (112 participants underwent CSF measurement: mean [SD] age, 63.4 [5.1] years; 31 [27.7%] male; and 107 underwent PIB-PET: mean [SD] age, 64.6 [5.3] years; 27 [25.2%] male), and 135 WRAP participants (85 participants underwent CSF measurement: mean [SD] age, 59.9 [6.0] years; 27 [31.8%] male; and 135 underwent PIB-PET: mean [SD] age, 59.6 [6.1] years; 43 [31.9%] male). In the PREVENT-AD cohort, individuals approaching their parent's onset age had lower CSF Aβ1-42 levels (range, 402-1597; B = -9.09, P = .04). This association was stronger in APOE4 carriers (B = -17.9, P = .03) and women (B = -19.8, P = .02). In the ACS cohort, the main association was replicated using PIB-PET data, and the sex interaction was replicated using CSF and PIB-PET data. In the WRAP cohort, the results were not replicated using cross-sectional data, but the main association and the APOE interaction were replicated using PIB-PET longitudinal data. CONCLUSIONS AND RELEVANCE These results suggest that proximity to parental symptom onsetmay help estimate Aβ biomarker changes in women or APOE4 carrier asymptomatic individuals with a parental history of sporadic AD