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Investigation of Cement Mortars Added Silicon Carbide Under Various Hydrochloric Acid Exposure Conditions
No full textIn this study, the effects of silicon carbide (SiC) addition on the properties of cement mortars subjected to hydrochloric acid
(HCl) exposure were evaluated. The primary objective was to assess the mechanical performance and durability enhancement
of cement mortars incorporating SiC under aggressive acidic conditions. Cement mortars were prepared by replacing
aggregates with SiC at ratios of 0%, 5%, 10%, and 15%, and were exposed to 10% HCl solution under three distinct
environmental conditions: continuous immersion in acid, alternating periods in air, and water exposure. To evaluate acid
resistance, the mass and compressive strength losses of the mortar specimens were measured before and after acid exposure.
Additionally, micro-computed tomography (micro-CT) was conducted to examine internal microstructural changes. Results
from mechanical tests and micro-CT analysis revealed that the incorporation of SiC significantly reduced the degradation
of the cement matrix by densifying the microstructure and lowering porosity, thereby enhancing resistance to acid attack.
These findings suggest that SiC can serve as an effective additive for improving the durability of cementitious materials in
acidic environmentsThe authors did not receive support from any organization for the submitted work. No funding was received for conducting this study
Spatiotemporal Gait and Fatigability in Multiple Sclerosis: Overground vs Treadmill Walking
No full textAchtergrond: Multiple sclerose (MS) is een neurodegeneratieve aandoening die vaak leidt tot gangproblemen, verergerd door vermoeibaarheid. Er is weinig bekend over hoe langdurig wandelen onder vaste snelheid het looppatroon beïnvloedt.
Methode: Negen personen met MS (pwMS) en achttien gezonde controles (HC) (29–64 jaar) voerden een 6-minuten wandeltest (6MWT) uit onder drie condities: overground, en loopband bij 50% en 80% van de maximale snelheid (T25FW). Gaitkenmerken (cadans, double support, single limb support (SLS), stapduur (SD), paslengte (SL) en zwaaifase) werden gemeten met sensoren (overground) of het GRAIL-systeem (loopband). Een lineair mixed model analyseerde groeps-, conditie- en interactie-effecten; procentuele veranderingen van minuut één tot zes werden berekend.
Resultaten: SLS en SD veranderden meer bij overground wandelen dan bij beide loopbandcondities. SL veranderde minder overground dan bij de trage loopbandconditie. Gemiddelde T25FW-snelheden waren 2,13 m/s (pwMS) en 2,10 m/s (HC); 6MWT-snelheden 1,63 m/s (pwMS) en 1,72 m/s (HC), zonder groepsverschillen.
Conclusie: De wandelconditie beïnvloedde de gangaanpassing: overground wandelen leidde tot grotere veranderingen in SLS en SD, kleinere veranderingen in SL en tot een grotere wandelafstand dan op de loopband
Assessment of Local Influence in the Fitting of Lactation Curves Using Nonlinear Mixed Models
No full textThe identification of highly influential animals in the estimation of model parameters is fundamental to understanding individual variation in lactation patterns and to identifying unique profiles, helping the researcher to gain insight into the phenomenon under investigation. In this study, we analyzed the lactation curves of 30 Saanen goats using a nonlinear mixed-effects model derived from Wood's lactation model and applied a local influence diagnostic tool to detect animals that may disproportionately affect parameter estimates. The data comes from an unbalanced experiment designed to study the effect of cumulative stress on the average weekly milk production. The diagnostic of local influence enabled the identification of some animals with an unusual profile. Through the parameters of the fitted model, we identified that the treatment effect was not statistically significant during the experimental week, but negatively affected milk production throughout the lactation period.This work was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) under Grant 001
Highly Active Electrocatalytic Alcohol Oxidation Coupled Hydrogen Production with Unsaturated Ni-O(OH) Coordination
No full textElectrocatalytic H-2 production coupled with valuable chemical fabrication is a highly desirable and sustainable approach for a carbon-neutral future. The prerequisite for its industrialization on a terawatt scale is the exploitation of an electrocatalyst that can operate steadily at current densities exceeding ampere levels. In this work, a Ni-O(OH)-C electrocatalyst consisting of an unsaturated Ni-O(OH) immobilized Ni crystal confined by carbon layers is proposed to realize the exceptional performance at the ampere-level current densities toward ethanol electrooxidation to acetic acid (EOR), hydrogen evolution reaction (HER), and their integrated system. This catalyst achieves a current density of 1 A cm(-2) for EOR and HER at a potential of 1.46 and -0.3 V (vs RHE), respectively. The unsaturated Ni-O(OH) species confined by carbon layers offer an optimized electronic structure and interfacial microenvironment to facilitate the HER kinetics, and they can deliver the electrophilic adsorbed oxygen to induce the EOR and block its unfavorable structural transformations during electrocatalysis. A Ni-O(OH)-C catalytic HER||EOR integration system offers a 220 mV voltage reduction at 1 A cm(-2) in comparison to that of Pt/C||RuO2 water electrolysis cell. A Zn-ethanol-air battery is equipped with a Ni-O(OH)-C catalyst, exhibiting >500 h of stable operation. Thanks to the extensive universality of the proposed alcohol systems, findings shine a bright future for the efficient and scalable manufacture of value-added chemicals, together with high-purity hydrogen production.W.X. and Q.S. contributed equally to this work. This research wassupported by the National Natural Science Foundation of China (No.22372127), the Natural Science Foundation of Hubei Province (Nos.ZRM2023000271, 2023AFB608)
Spatial variation in cause-specific premature mortality and its association with socioeconomic deprivation in Belgium from 2000 to 2019
No full textBackgroundPremature mortality risks vary in space and time among subpopulations and are influenced by numerous factors, including levels of socioeconomic deprivation. In Belgium, socioeconomic deprivation has recently been quantified using the Belgian Indices of Multiple Deprivation; however, its contribution to the spatial patterns of premature mortality has not yet been assessed. This study aims to investigate the variation in premature mortality risks and their association with socioeconomic deprivation.MethodsThe Belgian Index of Multiple Deprivation 2011 and its deprivation domains, including employment, income, education, housing, and crime, are used to measure overall and domain-specific deprivation in all 589 municipalities in Belgium between 2000 and 2019. We estimate the all-cause and cause-specific relative risks of dying prematurely using Bayesian hierarchical models.ResultsThe spatial patterns of relative risks varied by cause of death. The most common pattern observed was a North-South gradient, with higher risks in Wallonia and lower risks in Flanders. Subnational variation increased over time for all causes of death, differing by cause. Higher deprivation levels were linked to greater premature mortality risks, particularly associated with employment and housing deprivation. In both sexes, the strongest associations with deprivation were observed for deaths due to alcohol consumption, COPD, and diabetes mellitus.ConclusionThis study highlights the significant associations between socioeconomic deprivation and the risk of premature death in Belgium, revealing notable spatial disparities. The North-South gradient underscores the persistent regional inequalities, with Wallonia bearing the highest burden of premature mortality risks. These results emphasize the importance of addressing the complex interplay of socioeconomic factors in shaping health outcomes and the need for targeted public health interventions to reduce premature mortality and promote health equity across Belgium.Funding
This study was conducted as part of the ELLIS project (Monitoring and Mitigating Environmental Health Inequalities). funded by the Belgian Federal Science Policy (B2/191/P3/ELLIS).
Acknowledgements
This work was produced using data from Statbel (Directorate-general Statistics– Statistics Belgium) – Demobel (adaptation of the National Register), Census 1991, 2001, 2011, and IPCAL. Computational resources have been provided by the supercomputing facilities of the Université catholique de Louvain (CISM/ UCL) and the Consortium des Équipements de Calcul Intensif en Fédération Wallonie Bruxelles (CÉCI) funded by the Fond de la Recherche Scientifique de Belgique (F.R.S.-FNRS) under convention 2.5020.11 and by the Walloon Region. The authors want to thank Statbel and particularly Patrick Lusyne and Cloë Ost for preparing and making pseudonymized data available for research, the Centre for Demographic Research (DEMO) of UCLouvain for allowing us to access the data, the CISM team for managing the statistical servers, and the Federal Police Belgium – DRI – Business Police Accounting for providing us with data on crime
Validation of the Chimeric Fluorescent Reporter mClYFP-GlyRα2 for Nanoscale Activity Mapping of the Glycine Receptor alpha2
No full textHet behouden van excitatie/inhibitie (E/I) balans is cruciaal voor correcte informatieverwerking in de hersenen. Verstoring van deze balans speelt een rol bij diverse psychiatrische en neurologische aandoeningen. Glycinereceptoren (GlyRs), ligand-gated chloridekanalen die neuronale excitabiliteit moduleren, zijn hierbij essentieel. Hun werking is sterk contextafhankelijk en wordt bepaald door hun celtypespecifieke verdeling over subcellulaire compartimenten. Inzicht in hun subcellulaire lokalisatie is daarom van groot belang voor het begrijpen van hun (patho)fysiologische rol en voor het ontwikkelen van gerichte therapieën. Daarom werd een chimere fluorescente reporter, mClYFP-GlyRα2, ontwikkeld door GlyRα2 te fuseren met een gele fluorescerende chloride-sensor. Dit hulpmiddel maakt het mogelijk om GlyRα2 met hoge resolutie in levende cellen te visualiseren en gelijktijdig receptoractiviteit te meten. Het doel van deze studie was het valideren van mClYFP-GlyRα2. Single-channel patch-clampmetingen toonden aan dat het chimere eiwit de eigenschappen van het natieve kanaal behoudt. Live-cell TIRF-imaging bevestigde dat mClYFP zijn chloridegevoeligheid behoudt en real-time detectie van receptoractivatie mogelijk maakt. Deze resultaten valideren mClYFP-GlyRα2 als betrouwbare tool voor lokalisatie- en activiteitsonderzoek van GlyRα2 in levende cellen. Toepassing hiervan zal inzicht geven in de rol van GlyRα2 in uiteenlopende (patho)fysiologische contexten en bijdragen aan therapieontwikkeling
Schijnwerpers op detentie: de rol van het Europees Comité voor de Preventie van Foltering
No full textNotes on Semisimple Monoidal Categories of Rank Two
No full textIn this paper, we show that there are infinitely many semisimple monoidal categories of rank two over an algebraically closed field F\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}\end{document}.Funding
This work is supported by National Natural Science Foundation of China (Nos. 12071412, 12201545).
Acknowledgements
This work is supported by NNSF of China (Nos. 12071412,12201545)