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The implementation of polymer-based Li-metal batteries is hindered by their low coulombic efficiency and poor cycling stability attributed to continuous electrolyte decomposition. Enhancement of the solid electrolyte interface (SEI) stability is key to mitigating electrolyte decomposition. This study proposes surface-functionalized silica mesoball fillers to fabricate a composite polymer electrolyte (MSBM-CPE). As a result of surface modification, the polyethylene oxide matrix benefits from the uniform distribution of the filler, which provides a large surface area and Lewis acid sites. Molecular dynamics simulations reveal that the dissociation energy of lithium bis(trifluoromethanesulfonyl)imide in the filler is fourfold higher (-1.95 eV) than that of the filler-free electrolyte. Consequently, the MSMB-CPE diffusivity is 30 times higher than its filler-free counterpart. The MSMB-CPE of ionic conductivity of 1.16 × 10-2 S cm-1 @60 °C and a venerable Li-ion transference number of 0.81. The excellent compatibility of MSMB-CPE with the Li anode is demonstrated by its stable symmetric cell performance under high current density (200 µA cm-2 @60 °C) for over 5000 h. Approximately 85.60% retention capacity of the [Li/MSMB-CPE/LiFePO4] full cell after 700 cycles. Furthermore, compositional analysis reveals that the SEI layer in MSMB-CPE is smooth with fewer by-products at the electrolyte/Li interface.
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Lithium-ion batteries (LIBs) have revolutionized portable electronics, yet their conventional graphite anodes face capacity limitations. Integrating graphene and 3D molybdenum disulfide (MoS2) offers a promising solution. Ensuring a uniform distribution of 3D MoS2nanostructures within a graphene matrix is crucial for optimizing battery performance and preventing issues like agglomeration and capacity degradation. This study focuses on synthesizing a uniformly distributed paper wad structure by optimizing a composite of reduced graphene oxide RGO@MoS2through structural and morphological analyses. Three composites with varying graphene content were synthesized, revealing that the optimized sample containing 30 mg RGO demonstrates beneficial synergy between MoS2and RGO. The interconnected RGO network enhances reactivity and conductivity, addressing MoS2aggregation. Experimental results exhibit an initially superior capacity of 911 mAh g-1, retained at 851 mAh g-1even after 100 cycles at 0.1 A g-1current density, showcasing improved rate efficiency and long-term stability. This research underscores the pivotal role of graphene content in customizing RGO@MoS2composites for enhanced LIB performance.
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A distinguished triplet splitting pattern for the 14N-1H couplings in the proton signals of a series of protonated nitrogen bases-aliphatic and aromatic amines, as well as pyridines-with the weakly coordinating tetrakis(pentafluorophenyl)borate anion, [B(C6F5)4]-, is observed for the first time in nonaqueous media at room temperature. The effects of ion pairing, solvent parameters, and correlation between the δH, 1JNH, and pKa values are reported.
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Background: Limited interventions exist on reducing unwanted screen time (ST) among children from low- and middle-income countries (LMICs), so we developed and assessed the effectiveness of the program to lower unwanted media screen time (PLUMS) among children aged 2-5 years in Chandigarh, Union Territory, North India. Methods: An open-label randomized control parallel group trial per CONSORT guidelines was conducted among randomly selected 340 families with children aged 2-5 (±3 months) years in Chandigarh, India. PLUMS was implemented at the family level with a focus on modifying the home media environment and targeted individual-level interventions using parent and child modules for 2 months. A post-intervention (immediately) and a follow-up assessment after 6 months was done. During the follow-up period, the interaction was done passively via WhatsApp groups. The control group received routine healthcare services. Validated and standardized tools, including a digital screen exposure questionnaire with a physical activity component, preschool child behavior checklist, and sleep disturbance scale for children, were used to collect data at baseline, post-intervention, and follow-up periods. The primary outcome was the mean difference in ST (minutes/day) among children in the intervention group versus the control group. Generalized estimating equation (GEE) analysis was performed to adjust for clustering. Results: An equal number of families (n = 170) were randomly assigned to the intervention and control arms. In the post-intervention assessment, 161 and 166 families continued while, at the follow-up assessment, 154 and 147 were in the intervention and control arm, respectively. The mean difference in ST on a typical day [27.7 min, 95% Confidence Interval (CI) 5.1, 50.3] at the post-intervention assessment significantly (p < 0.05) decreased in the intervention (102.6 ± 98.5 min) arm as compared with the control (130.3 ± 112.8 min) arm. A significant reduction in ST (ß = -35.81 min, CI -70.6, -1.04) from baseline (ß = 123.1 min) to follow-up phase (ß = 116 min) was observed in GEE analysis. The duration of physical activity increased both at post-intervention (ß = 48.4 min, CI = +6.6, +90.3) and follow-up (ß = 73.4 min, CI = 36.2, 110.5) assessments in the intervention arm. Conclusion: The PLUMS intervention significantly reduced the children's mean ST on a typical day and increased the physical activity immediately post-intervention and during the 6-month follow-up period. These results might guide the policymakers to include strategies in the national child health programs in the Southeast Asia Region to reduce unwanted ST.Clinical trial registration: https://clinicaltrials.gov/, identifier CTRI/2017/09/009761.
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Tempo de Tela , Humanos , Pré-Escolar , Feminino , Masculino , Índia , Inquéritos e Questionários , Avaliação de Programas e Projetos de Saúde , Comportamento Infantil , TelevisãoRESUMO
A series of 1, 2, 4, 5-tetrasubstituted imidazole derivatives were synthesized and their antibiofilm potential against Candida albicans was evaluated in vitro. Two of the synthesized derivatives 5e (IC50 = 25 µg/mL) and 5m (IC50 = 6 µg/mL),displayed better antifungal and antibiofilm potential than the standard drug Fluconazole (IC50 = 40 µg/mL) against C. albicans. Based on the in vitro results, we escalated the real time polymerase chain reaction (RT-PCR) analysis to gain knowledge of the enzymes expressed in the generation and maintenance of biofilms and the mechanism of biofilm inhibition by the synthesized analogues. We then investigated the possible interactions of the synthesized compounds in inhibiting agglutinin-like proteins, namely Als3, Als4 and Als6 were prominently down-regulated using in-silico molecular docking analysis against the previously available crystal structure of Als3 and constructed structure of Als4 and Als6 using the SWISS-MODEL server. The stability and energy of the agglutinin-like proteins-ligand complexes were evaluated using molecular dynamics simulations (MDS). According to the 100 ns MDS, all the compounds remained stable, formed a maximum of 3, and on average 2 hydrogen bonds, and Gibb's free energy landscape analysis suggested greater affinity of the compounds 5e and 5m toward Als4 protein.Communicated by Ramaswamy H. Sarma.
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Meniscus tears are among the common knee injuries in sports, with arthroscopic meniscectomy being one of the most commonly performed orthopedic procedures. Return to sports of the same level following arthroscopic meniscectomy is an important aspect for athletes. Numerous factors may influence the time required for athletes to resume sports activities after meniscectomy. This prospective cohort study aimed to investigate the timeframe for returning to sports in athletes who underwent arthroscopic meniscectomy and to identify predictive factors that influence this return. Ninety sports persons who had undergone arthroscopic meniscectomy were included in this study. The patients were analyzed for their time to return to sports and nine proposed predictive factors that may influence their return to sports. Out of the 90 participants, 75 were able to return to their previous activity level, while the remaining 15 were unable to do so. Among the nine pre-defined factors studied, age older than 25 years (p < 0.0001), participation in non-contact sports (p < 0.0001), and engagement in recreational activities (p < 0.0001) were found to be statistically significant. In conclusion, this study reveals that with the increase in age, time to return to sports following arthroscopic meniscectomy increases. Additionally, athletes involved in non-contact sports and those having recreational sports activity levels experience greater delays in their return to sports as compared to athletes involved in combat and contact sports and athletes having elite and competitive sports levels, respectively.