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Comprehensive Stability Analysis of Haloperidol: Insights from Advanced Chromatographic and Thermal Analysis
No full textInternational audienceIn this study, we thoroughly investigated the stability of haloperidol using a comprehensive set of chromatographic and thermal analyses. Various stress conditions were examined, including exposure to oxidizing agents (such as hydrogen peroxide), dry heat, photolytic conditions, and acid and alkaline hydrolysis. Significant degradation was observed in acidic and alkaline environments, leading to the formation of degradation by-products, specifically DPA, DPB, DPC, and DPD for acidic and basic conditions. In contrast, haloperidol demonstrated robust stability under photolytic, oxidative, and dry-heat conditions. For the analysis of the drug and its degradation products, a C-18 column was employed, coupled with a mobile phase consisting of methanol and a phosphate buffer (pH = 9.8) in a 90:10 (v/v) ratio. The analytical method was rigorously validated according to ICH Q2 (R1) guidelines, ensuring its accuracy and reliability. This method exhibited excellent linearity within a concentration range of 1 to 50 µg/mL, with an R2 of 0.999. Additionally, this method is applicable to commercial formulations, without the need for prior extraction. LC-MS/MS analysis revealed distinct m/z values and fragmentation spectra corresponding to the degradation products, including an impurity not documented in the European Pharmacopoeia monograph for the drug. Three additional degradation products were identified based on m/z values and base fragments. Thermal analyses, including thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and differential thermal analysis (DTA), provided further evidence of the active ingredient’s thermal stability, with a melting temperature of approximately 150 °C. These results collectively offer valuable insights into the degradation behavior of haloperidol, providing critical implications for its pharmaceutical quality and integrity under various environmental conditions
A Novel Halophilic Bacterium for Sustainable Pollution Control: From Pesticides to Industrial Effluents
No full textInternational audienceThis study investigates the bioremediation potential of Marinobacter-hydrocarbonoclasticus SDK644, a strain that has been isolated from petroleum-contaminated environments, for the degradation of the herbicide metribuzin and the treatment of slaughterhouse effluent. The strain’s bacterial growth and degradation capacity were assessed under varying conditions, including different metribuzin concentrations, pH values, temperatures, and inoculum sizes. The strain demonstrated optimal growth at a metribuzin concentration of 20 mg/L, with an optical density (OD600) of 0.408 after 96 h. At this concentration, 80% of the chemical oxygen demand (COD) was reduced over 144 h. The optimal growth conditions for M. hydrocarbonoclasticus SDK644 were identified as a pH of 7 and a temperature of 30 °C, where the enzymatic activity and degradation efficiency were maximized. Additionally, the treatment of slaughterhouse effluent showed significant reductions in organic pollution, with the COD and biochemical oxygen demand (BOD5) decreasing by 80% (from 1900 mg/L to 384 mg/L) and 81% (from 1700 mg/L to 320 mg/L), respectively, within seven days. The strain also facilitated ammonium removal and promoted nitrification, indicating its suitability for treating high-organic-load wastewater. Notably, the visual transformation of the effluent, from a dark red color to a clear state, further highlighted the efficiency of the treatment process. This research highlights the adaptability of M. hydrocarbonoclasticus SDK644 to a wide range of environmental conditions and its efficiency in biodegrading metribuzin and treating complex wastewater. The findings demonstrate the strain’s potential as a sustainable solution for mitigating organic pollution in agricultural runoff, pesticide-contaminated water, and industrial effluents
Acceleration-based Inner-loop Control and MPC for Aerial Robots: Advantages and Drawbacks
No full textInternational audienceThis paper studies the application of a fast inner-loop controller on top of a Nonlinear Model Predictive Control (NMPC) to increase tracking performances of aerial robots in presence of disturbances and model mismatches. We investigate the use of Incremental Nonlinear Dynamic Inversion (INDI) and Time Delay Control (TDC), discussing their close relations. Finally, a TDC formulation is developed as inner tracking loop running at 1 kHz, and applied to a NMPC. Close-to-real simulations with a fully-actuated hexarotor demonstrates the effectiveness of the inner-loop control and its main drawbacks in presence of input saturation
Demarcation as symbolic politics: insights from conservation territories expansion in Central Africa
No full textInternational audienceThe expansion of conservation territories has become an important symbol for measuring the success of biodiversity conservation policies. However, overreliance on symbolic actions risks distorting policy decisions, overstating achievements while hiding inefficiencies. To ensure fair and sustainable conservation efforts, it is essential to critically assess whether prioritising territorial expansion represents the most effective response to the biodiversity crisis. In 2000, a transnational conservation organisation (WWF) organised an expert meeting in Gabon to map out conservation priorities in Central Africa, resulting in the virtual demarcation of vast forest areas. These areas became focal points for conservation efforts over decades. Using the Maiko Tayna Kahuzi-Biega (MTKB) landscape conservation in the eastern Democratic Republic of Congo (DRC) as a case study, this paper questions whether conservation expansion within these initiatives has led to symbolic or substantive outcomes in achieving fair and sustainable conservation. Our findings reveal that while conservation expansion attracts international donor funding, it remains largely symbolic. Legal designations and mapped territories create an illusion of progress, diverting resources from the substantive actions needed to achieve equitable and sustainable outcomes. Simply designating conservation areas does not ensure legitimacy or authority on the ground, nor does it address the social inequalities that undermine conservation efforts. The difficulties faced by conservation initiatives in the MTKB landscape cannot be attributed solely to the persistent conflict in the region. Even after years of instability, transnational conservation actors and donors remain engaged in the region, pursuing global agendas that prioritise the expansion of conservation territories. The concept of “symbolic politics”, as developed by Edelman, provides a valuable theoretical framework to explain why conservation expansion policies persist despite significant evidence of their inability to achieve fair and sustainable outcomes
Contribution of ECOSTRESS thermal imagery to wetland mapping: Application to heathland ecosystems
No full textInternational audienceWhile wetlands have been extensively studied using optical and radar satellite imagery, thermal imagery has been used less often due its low spatial – temporal resolutions and challenges for emissivity estimation. Since 2018, spaceborne thermal imagery has gained interest due to the availability of ECOSTRESS data, which are acquired at 70 m spatial resolution and a 3–5 revisit time. This study aimed at comparing the contribution of ECOSTRESS time-series to wetland mapping to that of other thermal time-series (i.e., Landsat-TIRS, ASTER-TIR), Sentinel-1 SAR and Sentinel-2 optical satellite time-series, and topographical variables derived from satellite data. The study was applied to a 209 km2 heathland site in north-western France that includes riverine, slope, and flat wetlands. The method used consisted of four steps: (i) four-year time-series (2019–2022) were aggregated into dense annual time-series; (ii) the temporal dimension was reduced using functional principal component analysis (FPCA); (iii) the most discriminating components of the FPCA were selected based on recursive feature elimination; and (iv) the contribution of each sensor time-series to wetland mapping was assessed based on the accuracy of a random forest model trained and tested using reference field data. The results indicated that an ECOSTRESS time-series that combined day and night acquisitions was more accurate (overall F1-score: 0.71) than Landsat-TIRS and ASTER-TIR time-series (overall F1-score: 0.40–0.62). A combination of ECOSTRESS thermal images, Sentinel-2 optical images, Sentinel-1 SAR images, and topographical variables outperformed the sensor-specific accuracies (overall F1-score: 0.87), highlighting the synergy of thermal, optical, and topographical data for wetland mapping
Variétés de la croyance : religion, science, inconscient
No full textInternational audienceAbstractObjectiveThis article focuses on the phenomenon of religious belief. It aims to shed light on the epistemology of belief from the 20th century to today. From religious belief to belief in science in the current era, particularly through the evolution of imagery, belief can also concern a subject in its psychic utility.MethodAfter having noted different neurocognitive experiences of belief and retaining some indications, we take up again the hypothesis of the function of religious belief in the psychic economy. A link between the fragility of the symbolic in psychosis, the identification of the melancholic position and the psychic necessity of a belief with the value of conviction, therefore delusional, is illuminated; the reading of the correspondence of Jacques Fesch attempts to clarify the hypothesis unfolded.ResultsImaging makes it possible to identify the activation of certain brain areas during moments of prayer; it makes it possible to diagnose post-ictal psychosis. Imaging and the identification of certain brain activations cannot shed light on the function of belief for a subject. We suggest that religious belief on the side of conviction constitutes a sufficiently solid psychological support for Jacques Fesch who is called upon to respond at a moment in his existence. Religious belief as a compass is a singular way for certain subjects to orient their existence where landmarks are not solidly subjectivized.DiscussionIf belief allows one to bear existence, the subject can nevertheless feel the fragility of his position through massive anxiety. To counter this, Jacques Fesch finds a way to consolidate his delusion in a megalomaniacal, sacrificial position, where God will welcome him as a chosen one.ConclusionThe religious subject trusts in God, while the subject of science believes in the laws of the brain. In both cases, the subject does not take responsibility for his cause, which is sometimes necessary, as demonstrated by the delusional logic of Jacques Fesch. In practice, belief can therefore be welcomed as a solution, a conviction for a lost subject who testifies to a subjective malaise or as a construction that testifies to a not wanting to know what unconsciously causes suffering. The practitioner will direct his act according to the subjective position of the subject.RésuméObjectifCet article s’intéresse au phénomène de la croyance religieuse. Il veut éclairer l’épistémologie de la croyance du XXème siècle à aujourd’hui. De la croyance religieuse à la croyance en la science dans l’époque actuelle notamment par l’évolution des imageries, la croyance peut aussi concerner un sujet dans son utilité psychique.MéthodeAprès avoir relevé différentes expériences neurocognitives de la croyance et en retenir quelques indications, nous reprenons l’hypothèse de la fonction de la croyance religieuse dans l’économie psychique. Un lien entre la fragilité du symbolique dans la psychose, le repérage de la position mélancolique et la nécessité psychique d’une croyance à valeur de conviction, donc délirante, est éclairé ; la lecture de la correspondance de Jacques Fesch tente de préciser l’hypothèse dépliée.RésultatsL’imagerie permet de repérer l’activation de certaines zones cérébrales lors de moment de prières ; elle permet de diagnostiquer la psychose post-ictale. L’imagerie et le repérage de certaines activations cérébrales ne peuvent éclairer la fonction de la croyance pour un sujet. Nous avançons que la croyance religieuse du côté de la conviction constitue un appui psychique suffisamment solide pour Jacques Fesch qui est appelé à répondre à un moment de son existence. La croyance religieuse comme boussole est une façon singulière pour certains sujets d’orienter leur existence là où des repères ne sont pas solidement subjectivés.DiscussionSi la croyance permet de supporter l’existence, le sujet peut néanmoins ressentir la fragilité de sa position par une angoisse massive. Pour y parer, Jacques Fesch trouve à consolider son délire dans une position mégalomaniaque, sacrificielle, où Dieu l’accueillera comme un élu. ConclusionLe sujet religieux se confie à Dieu, tandis que le sujet de la science croit aux lois du cerveau. Dans ces deux cas, le sujet ne se fait pas responsable de sa cause, ce qui est parfois nécessaire, comme le démontre la logique délirante de Jacques Fesch. Dans la pratique, la croyance peut donc être accueillie comme une solution, une conviction pour un sujet égaré qui témoigne d’un malaise subjectif ou comme une construction qui témoigne d’un ne pas vouloir savoir ce qui cause inconsciemment la souffrance. Le praticien orientera son acte en fonction de la position subjective du sujet
Closing the intention‐behaviour gap in physical activity: The moderating effect of individual differences in the valuation of physical effort
No full textInternational audienceObjective Intention is a proximal antecedent of physical activity, but it often falls short of driving actual engagement in physical activity. Recently, it was suggested that the valuation of physical effort may explain the intention–behaviour gap. However, this hypothesis has not been formally tested. We aimed to examine whether individual differences in approach and avoidance tendencies towards physical effort moderate the strength of the association between intention and behaviour. Methods Four hundred and one English‐speaking Canadian participants completed two online surveys separated by 1 week. Intention strength and individual differences in the tendencies to approach and avoid physical effort were first assessed, and moderate‐to‐vigorous physical activity was self‐reported 7 days later. The moderating effect of approach and avoidance tendencies towards physical effort on the association between intention and physical activity was tested using linear regression models. Results Individual differences in approach tendencies (β = .11, p = .007), avoidance tendencies (β = −.11, p = .005) and in relative approach (vs avoidance) tendencies towards physical effort (β = .11, p = .005) moderated the association between the intention and moderate‐to‐vigorous physical activity. As expected, the association between intention and physical activity was stronger as approach tendencies towards physical effort increased, but weaker as avoidance tendencies increased. However, this moderating effect was only significant for vigorous physical activity, not for moderate physical activity. Conclusion This study suggests that individual differences in the valuation of physical effort represent a relevant moderator of the intention–behaviour gap in physical activity, especially the most vigorous ones
Mise en oeuvre de la comodalité dans un enseignement de 1 ère année à l'Université
No full textInternational audienceCet article explore la mise en place de la comodalité dans un cours universitaire de première année. La comodalité permet aux étudiants de choisir entre présentiel et distanciel, offrant ainsi plus de flexibilité. Les résultats montrent un fort taux de satisfaction et des taux de réussite comparables à ceux des modalités traditionnelles
Breast Cancer Screening in Women With Multiple Sclerosis: A Mixed‐Methods Study
No full textInternational audienceABSTRACT Background There is little information on breast cancer screening (BCS) practices in women with multiple sclerosis (WwMS). Objective To assess and compare BCS rates in WwMS and in the general population and identify barriers and facilitators. Methods In a 2012–2020 cohort study, we identified 47,166 WwMS without a history of cancer and matched them (up to 1:4) to 184,124 controls from the French national medico‐administrative database. Mammography rates were compared according to age, city‐level socio‐economic status, period, and DMT use. We used logistic and negative binomial models to identify factors associated with BCS adherence in WwMS. We also carried out semistructured interviews with 20 WwMS and analyzed them using the empirically inductive method. Results Compared with controls, fewer WwMS underwent BCS at least once (69.9% vs. 76.7%, p < 0.001) and had a lower biennial mammography rate (0.55 vs. 0.63; p < 0.001). Rate differences increased with age. Once stratified on DMT, age‐standardized rates only differed in the non‐treated group (0.51 vs. 0.64; p < 0.001). Factors associated with lower mammography rates in WwMS were city‐level socio‐economic status (mostdeprived vs. least deprived; IRR 0.88 95% CI [0.86–0.91]), long MS duration (16–25 years: 0.91 [0.89–0.94]; ref: ≤ 5) and hospitalization (MS‐related: 0.85 [0.82–0.88]; non‐MS‐related: 0.92 [0.89–0.94]). However, DMT use was associated with higher mammography rates (high efficacy: 1.17 [1.14–1.21]; moderate efficacy: 1.18 [1.16–1.20]). Barriers were physical disability and feeling of excessive medicalization. Facilitators were disability‐accessible care and perception of BCS as a routine procedure. Conclusion BCS among WwMS is suboptimal, especially among those not treated by DMT, and needs to be improved
Le contextualisme conceptuel et la polysémie mentale
No full textInternational audienceIl y a deux François Recanati : l'un est philosophe du langage, l'autre philosophe de l'esprit. Tous deux sont contextualistes. Mais il y a une différence entre leurs formes respectives de contextualisme. En philosophie du langage, le contextualisme radical de Recanati repose sur une double généralisation de la dépendance contextuelle -celle de l'indexicalité à tous les termes référentiels, et celle de la polysémie à toutes les expressions de classe ouverte. En philosophie de l'esprit, l'indexicalité est aussi quasi-généralisée, à travers l'identification des concepts singuliers à des fichiers mentaux, qui sont eux-mêmes conçus comme des indexicaux. Mais la polysémie ne fait pas l'objet d'une généralisation parallèle au niveau des concepts. Le présent article vise à encourager les deux Recanati à harmoniser leurs positions. Il invite à postuler des concepts/fichiers polysémiques, et vise à montrer qu'une telle postulation, contrairement à ce qu'on pourrait croire, ne remet en cause ni le contextualisme radical en philosophie du langage, ni les principes fondamentaux du modèle des fichiers mentaux