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1.
Digit Health ; 10: 20552076241242795, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38571876

RESUMEN

Objective: This study aimed to determine the usability of the EMPOWER-SUSTAIN Self-Management Mobile App© and evaluate the factors associated with its usability among patients with cardiovascular risk factors in primary care. Methodology: This was a cross-sectional study, conducted among patients aged ≥ 18 years with cardiovascular risk factors attending a university primary care clinic. Patients were given the app to use for at least three months. Those who fulfilled the eligibility criteria were recruited. Data gathered were on sociodemographic, clinical characteristics, self-management support by doctors, utilisation of the app at home and social support in using the app. The previously translated and validated Malay version of the mHealth App Usability Questionnaire was used to measure usability. The mean usability score was calculated and linear regressions analysis was conducted to determine the factors associated with the usability of the app. Results: A total of 247 patients with at least one cardiovascular risk factor(s) were recruited. The mean age was 60.2 (±8.2). The majority were Malays (86.2%) and half of them were males (52.2%). The total mean (±SD) usability score was 5.26 (±0.67) indicating a high usability of the app. Usability of the app declined with increasing age in the simple linear regressions analysis. The multiple linear regressions yielded that being Malay (b = 0.31, 95% CI 0.08,0.54), using the app at home to understand their medications (b = 0.33, 95% CI 0.12,0.53) and having social support from family members and friends (b = 0.28, 95% CI 0.07,0.49) were significantly associated with higher usability of the app. Conclusion: The usability of the EMPOWER-SUSTAIN Self-Management Mobile App© was high among patients with cardiovascular risk factors in our primary care clinic. This finding supports the widespread use of this app among our patients. Involvement of family members and friends should be encouraged to improve the usability of the app.

2.
Sci Rep ; 14(1): 2992, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316829

RESUMEN

Mechanical stress can directly activate chemical reactions by reducing the reaction energy barrier. A possible mechanism of such mechanochemical activation is structural deformation of the reactant species. However, the effect of deformation on the reaction energetics is unclear, especially, for shear stress-driven reactions. Here, we investigated shear stress-driven oligomerization reactions of cyclohexene on silica using a combination of reactive molecular dynamics simulations and ball-on-flat tribometer experiments. Both simulations and experiments captured an exponential increase in reaction yield with shear stress. Elemental analysis of ball-on-flat reaction products revealed the presence of oxygen in the polymers, a trend corroborated by the simulations, highlighting the critical role of surface oxygen atoms in oligomerization reactions. Structural analysis of the reacting molecules in simulations indicated the reactants were deformed just before a reaction occurred. Quantitative evidence of shear-induced deformation was established by comparing bond lengths in cyclohexene molecules in equilibrium and prior to reactions. Nudged elastic band calculations showed that the deformation had a small effect on the transition state energy but notably increased the reactant state energy, ultimately leading to a reduction in the energy barrier. Finally, a quantitative relationship was developed between molecular deformation and energy barrier reduction by mechanical stress.

3.
Phys Chem Chem Phys ; 26(1): 278-292, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38059507

RESUMEN

The growth of protective tribofilms from lubricant antiwear additives on rubbing surfaces is initiated by mechanochemically promoted dissociation reactions. These processes are not well understood at the molecular scale for many important additives, such as tricresyl phosphate (TCP). One aspect that needs further clarification is the extent to which the surface properties affect the mechanochemical decomposition. Here, we use nonequilibrium molecular dynamics (NEMD) simulations with a reactive force field (ReaxFF) to study the decomposition of TCP molecules confined and pressurised between sliding ferrous surfaces at a range of temperatures. We compare the decomposition of TCP on native iron, iron carbide, and iron oxide surfaces. We show that the decomposition rate of TCP molecules on all the surfaces increases exponentially with temperature and shear stress, implying that this is a stress-augmented thermally activated (SATA) process. The presence of base oil molecules in the NEMD simulations decreases the shear stress, which in turn reduces the rate constant for TCP decomposition. The decomposition is much faster on iron surfaces than iron carbide, and particularly iron oxide. The activation energy, activation volume, and pre-exponential factor from the Bell model are similar on iron and iron carbide surfaces, but significantly differ for iron oxide surfaces. These findings provide new insights into the mechanochemical decomposition of TCP and have important implications for the design of novel lubricant additives for use in high-temperature and high-pressure environments.

4.
Eur Rev Med Pharmacol Sci ; 27(13): 6401-6413, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37458660

RESUMEN

OBJECTIVE: Recently, lumpy skin disease (LSD) has been spread over the Asian, European, and Middle Eastern regions making it a significant hazard to the chain of cattle production, milk production, and human milk consumption, requiring prompt attention. Lumpy skin disease virus has high morbidity and low fatality rates, but its infections have led to terrible economic and agricultural consequences. Although live-attenuated vaccines have been commercialized, farmers in different regions have not taken them well because of the allergic responses against the vaccines. The study aims to develop an mRNA-based vaccine candidate for LSDV, using immunoinformatic approaches to minimize allergenicity and homology while maximizing immunogenic potential. MATERIALS AND METHODS: The study used extensive immunoinformatic approaches to shortlist five proteins from the LSDV genome that belong to the transmembrane region and are crucial in early viral interaction with host cells. The B-cell and T-cell-specific epitopes were chosen based on non-allergenicity, antigenicity, non-homology, surface accessibility, and lower IC50 inhibition values. The construct's stability, hydrophilicity, and antigenic potential were analyzed using the instability index, Grand Average of Hydropathicity (GRAVY) index, and antigenicity, respectively. RESULTS: We selected a total of 34 epitopes, consisting of 12 B-cell-specific epitopes and 22 T-cell-specific epitopes. These epitopes were chosen based on their characteristics such as non-allergenicity, antigenicity, non-homology, surface accessibility, and lower IC50 inhibition values. Specifically, 11 epitopes were selected for Major Histocompatibility Complex-I, and another 11 epitopes were chosen for Major Histocompatibility Complex-II. The inclusion of the RS09 adjuvant enhanced the immunogenic potential of the vaccine. The instability index was found to be 38.60. Additionally, the GRAVY index, indicating hydrophilicity, was calculated as -0.151. Furthermore, the antigenicity value of 0.6073 confirmed its potential to elicit an immune response. Further supporting its immunogenic potential, strong immune stimulation was observed, with IgM+IgG titers reaching 6,000 (arbitrary units) and IFNg titers measuring 400,000 ng/mL. These results provide additional evidence of the vaccine's ability to stimulate a robust immune response. CONCLUSIONS: The study results indicate that the developed mRNA-based vaccine candidate for LSDV has high immunogenic potential and could serve as an effective alternative to live-attenuated vaccines. Further experimental validations are required to test its efficacy. The study also highlights the potential of the One-Health approach to tackle non-zoonotic diseases that have significant consequences for the environment and humanity.


Asunto(s)
Virus de la Dermatosis Nodular Contagiosa , Salud Única , Vacunas Virales , Animales , Bovinos , Humanos , Virus de la Dermatosis Nodular Contagiosa/genética , Vacunas Atenuadas/genética , Vacunas Virales/genética , Epítopos , ARN Mensajero/genética
5.
Small ; 19(37): e2301515, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37162454

RESUMEN

Two-dimensional (2D) lamellar materials are normally capable of rendering super-low friction, wear protection, and adhesion reduction in nanoscale due to their ultralow shear strength between two basal plane surfaces. However, high friction at step edges prevents the 2D materials from achieving super-low friction in macroscale applications and eventually leads to failure of lubrication performance. Here, taking graphene as an example, the authors report that not all step edges are detrimental. The armchair (AC) step edges are found to have only a minor topographic effect on friction, while the zigzag (ZZ) edges cause friction two orders of magnitude larger than the basal plane. The AC step edge is less reactive and thus more durable. However, the ZZ structure prevails when step edges are produced mechanically, for example, through mechanical exfoliation or grinding of graphite. The authors found a way to make the high-friction ZZ edge superlubricious by reconstructing the (6,6) hexagon structure to the (5,7) azulene-like structure through thermal annealing in an inert gas environment. This will facilitate the realization of graphene-based superlubricity over a wide range of industrial applications in which avoiding the involvement of step edges is difficult.

6.
Faraday Discuss ; 241(0): 194-205, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36134558

RESUMEN

Mechanochemical activation has created new opportunities for applications such as solvent-free chemical synthesis, polymer processing, and lubrication. However, mechanistic understanding of these processes is still limited because the mechanochemical response of a system is a complex function of many variables, including the direction of applied stress and the chemical features of the reactants in non-equilibrium conditions. Here, we studied shear-activated reactions of simple cyclic organic molecules to isolate the effect of chemical structure on reaction yield and pathway. Reactive molecular dynamics simulations were used to model methylcyclopentane, cyclohexane, and cyclohexene subject to pressure and shear stress between silica surfaces. Cyclohexene was found to be more susceptible to mechanochemical activation of oxidative chemisorption and subsequent oligomerization reactions than either methylcyclopentane or cyclohexane. The oligomerization trend was consistent with shear-driven polymerization yield measured in ball-on-flat sliding experiments. Analysis of the simulations showed the distribution of carbon atom sites at which oxidative chemisorption occurred and identified the double bond in cyclohexene as being the origin of its shear susceptibility. Lastly, the most common reaction pathways for association were identified, providing insight into how the chemical structures of the precursor molecules determined their response to mechanochemical activation.

7.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-626461

RESUMEN

Aims: Polyvinyl chloride (PVC) is the most widely used and environmentally damaging plastic. Processing, production and disposal of PVC cause release of toxic chlorine based compounds into environment. The objective of the present study was to assess the biodegradability of cellulose blended PVC by white rot fungi i.e. Phanerochaete chrysosporium. Methodology and results: Biodegradability of the strain for the polymer was tested on plate assay, sturm test, soil burial and shake flask experiments. The biodegradability of the polymer was determined by visual changes, plate assay and carbon dioxide production. Morphological changes in the polymer such as pits, extensive spotting, clear surface erosion, fungal attachment, roughening and deterioration of some parts were observed using scanning electron microscopy. Chemical changes like appearance and shortening of peaks using fourier transform infrared spectroscopy also confirmed the biodegradability of the polymer. Conclusion, significance and impact of study: The present study confirmed that mixing of small amount of cellulose increases the hydrophilicity of the polymer and lead to its microbial degradation and Phanerochaete chrysosporium has great potential for the treatment of solid waste containing plastics.

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