Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Nat Rev Chem ; 8(7): 492, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38849619
2.
Dalton Trans ; 53(15): 6779-6790, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38535981

RESUMO

Inherently disordered structures of carbon nitrides have hindered an atomic level tunability and understanding of their catalytic reactivity. Starting from a crystalline carbon nitride, poly(triazine imide) or PTI/LiCl, the coordination of copper cations to its intralayer N-triazine groups was investigated using molten salt reactions. The reaction of PTI/LiCl within CuCl or eutectic KCl/CuCl2 molten salt mixtures at 280 to 450 °C could be used to yield three partially disordered and ordered structures, wherein the Cu cations are found to coordinate within the intralayer cavities. Local structural differences and the copper content, i.e., whether full or partial occupancy of the intralayer cavity occurs, were found to be dependent on the reaction temperature and Cu-containing salt. Crystallites of Cu-coordinated PTI were also found to electrophoretically deposit from aqueous particle suspensions onto either graphite or FTO electrodes. As a result, electrocatalytic current densities for the reduction of CO2 and H2O reached as high as ∼10 to 50 mA cm-2, and remained stable for >2 days. Selectivity for the reduction of CO2 to CO vs. H2 increases for thinner crystals as well as for when two Cu cations coordinate within the intralayer cavities of PTI. Mechanistic calculations have also revealed the electrocatalytic activity for CO2 reduction requires a smaller thermodynamic driving force with two neighboring Cu atoms per cavity as compared to a single Cu atom. These results thus establish a useful synthetic pathway to metal-coordination in a crystalline carbon nitride and show great potential for mediating stable CO2 reduction at sizable current densities.

3.
Patient Educ Couns ; 118: 107993, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37844427

RESUMO

OBJECTIVE: We examined the effectiveness of a behavioral intervention in promoting cervical cancer screening among women living with HIV (WLWH) in Ghana. METHODS: A Mixed-methods study was conducted involving 83 WLWH, who were randomly assigned to an intervention group (n = 42) to receive voice-recorded messages based on the 3 R model (Reframing, Reprioritizing, and Reforming) or a control group (n = 41) to receive standard care. The primary outcomes were screening uptake and HPV prevalence. Other outcomes were the acceptability, appropriateness, and feasibility of the intervention. RESULTS: The intervention group had a 100% screening rate, and the control group had a 14.63% screening rate. The prevalent rate of high-risk (hr)-HPV genotypes among the women was 67.5% (95%C.I: 0.56-0.77). Over 48% of the participants had multiple hr-HPV genotypes, 64.29% had HPV16/18/45%, and 73.21% had HPV 31/33/45/52/58. Of the women (89.30%) who screened positive, 60% of them were diagnosed and treated for pre-cancer lesions. The intervention messages were acceptable (encourage proactive behavior), feasible (simple, easy to understand), and appropriate (helpful, informative). Facilitators and barriers to self-sampling were identified. CONCLUSION: Combining the 3 R model with self-sampling increases cervical cancer screening among WLWH. PRACTICE IMPLICATION: Healthcare professionals and policymakers can use this model to increase cervical cancer screening.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Detecção Precoce de Câncer/métodos , Infecções por HIV/diagnóstico , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Programas de Rastreamento/métodos , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle
4.
Vaccines (Basel) ; 11(5)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37242995

RESUMO

The study examined whether the 3R (reframe, prioritize, and reform) communication model intervention can impact parents' and adolescents' HPV vaccination acceptability. We used face-to-face methods to recruit participants from three local churches in the Ashanti Region of Ghana. Participants completed pre- and post-intervention assessments based on the validated Theory of Planned Behavior survey. We organized two face-to-face presentations for parents and adolescents separately for parents (n = 85) and adolescents (n = 85). Participants' post-intervention vs. pre-intervention scores for attitude (mean = 35.46 ± SD = 5.46 vs. mean = 23.42 ± SD = 8.63), knowledge (M = 28.48 ± SD = 5.14 vs. M = 16.56 ± SD = 7.19), confidence (M = 8.96 ± SD = 3.43 vs. M = 6.17 ± SD = 2.84), and intention for vaccine acceptance (M = 4.73 ± SD = 1.78 vs. M = 3.29 ± SD = 1.87) increased significantly (p < 0.001). The intervention showed that for every one-unit increase in the participants' self-confidence and attitude scores, the odds of the HPV vaccination acceptability increased by 22% (95% CI: 10-36) and 6% (95% CI: 0.1-12), respectively. Intention for vaccine acceptance, F (1167) = 6.89, and attitude toward vaccination, F (1167) = 19.87, were significantly higher among parents than adolescents (p < 0.001), after controlling for the baseline scores. These findings suggest that the intervention targeting parents' and adolescents' attitudes and knowledge has the potential to increase HPV vaccination acceptance in Ghana.

5.
J Mol Graph Model ; 120: 108419, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36709703

RESUMO

A theoretical study on the reaction mechanisms of the addition of transition metal oxo complexes of the type MO3Cl (M = Mn, Tc, and Re) to tetramethylethylene (TME) is presented. Theoretical calculations using B3LYP/LACVP* and M06/LACVP* (LACVP* is a combination of the 6-31G(d) basis set along with LANL2DZ pseudopotentials on the metallic centres) were performed and the results are discussed within the framework of reaction energetics. The nature of the stability of the reaction mechanisms was equivalent for both theories. However, the M06/LACVP* simulations generally had slightly lower energies and shorter bond lengths compared to the B3LYP/LACVP* computations. Furthermore, it was observed that the reaction does not proceed via the stepwise reaction mechanism due to kinetic and thermodynamic instabilities. Epoxidation was also found to occur via the [2 + 2] concerted reaction mechanism for the MO3Cl (M = Tc and Re) whereas the permanganyl chloride complex epoxidizes TME via the [2 + 1] concerted reaction mechanism on the singlet potential energy surface (PES). Dioxylation was observed to proceed via the [3 + 2] route for the addition of MO3Cl (M = Tc and Re) and TME. Results indicate that all reaction surfaces were unselective except for the permanganyl chloride catalyzed surface which leads to the formation of epoxides exclusively. Changes in temperatures from 298.15 K to 373.15 K, resulted in kinetically and thermodynamically unstable reaction pathways as the activation and reaction energies increased generally. On the singlet PES, the rate constant calculations showed that the [3 + 2] catalyzed surface reaction mechanism leading to dioxylation was faster than the [2 + 2] mechanism in cases where plausible. Theoretical values from the global reactivity parameters, namely the chemical hardness, chemical potential, electrophilic and nucleophilic indices, are in good correlation with the DFT activation and reaction energies at both levels of theories. Thus, as the electrophilic nature of the metal decreases from Mn to Re, so do the activation and reaction energies increase from Mn to Re, indicating that the higher the electrophilicity of the metal centre, the more spontaneous the oxidation reaction.


Assuntos
Cloretos , Complexos de Coordenação , Oxirredução , Modelos Teóricos , Complexos de Coordenação/química
6.
J Mol Model ; 28(4): 94, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35314884

RESUMO

The oxidation of ethylene catalyzed by manganese and technetium oxo complexes of the type MO3L (M = Tc, Mn, and L = O-, Cl-, F-, OH-, Br-, I-) on both singlet and triplet potential energy surfaces (PESs) have been studied. All molecular structures were stable on the singlet PES except for the formation of the dioxylate intermediate for the MnO3L (L = O-, Cl-, F-, OH-, Br-, I-) catalyzed pathway. Frontier molecular orbital calculations showed that electrons flow from the HOMO of ethylene into the LUMO of the metal-oxo complex for all complexes studied except for MO3L (M = Tc, Mn, and L = O-) where the vice versa occurs. In the reaction of both TcO3L and MnO3L (L = O-, Cl-, F-, OH-, Br-, I-) with ethylene, it was observed that the formation of the dioxylate intermediate along the [3 + 2] addition pathway on the singlet reaction surface is both kinetically and thermodynamically favorable over its formation via the [2 + 2] pathway. Furthermore, it was observed that TcO4- and MnO4- catalyzed pathways exclusively form diols on the singlet PES. The formation of epoxides on the singlet surface is kinetically favorable through the [2 + 1] and [2 + 2] channel for the MnO3L (L = F-, Cl-, Br-, I-, OH-) and TcO3L (L = F-, Cl-, Br-, I-, OH-) catalyzed surfaces respectively. In all cases, the TcO3L complexes were found to be polar compared to the MnO3L complexes. The MnO4- (singlet) and MnO3F (singlet) are the best catalysts for the exclusive formation of the diols and epoxides respectively.

7.
Pan Afr Med J ; 40: 76, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804343

RESUMO

INTRODUCTION: COVID-19 pandemic has had a greater psychological impact on patients with chronic ailments such as diabetes mellitus, tuberculosis, and HIV/AIDS compared to those without chronic conditions. We explored the psychological impacts of COVID-19 among people living with diabetes mellitus in Ghana. METHODS: this study employed a hospital-based cross-sectional design involving 157 diabetes mellitus patients aged 20 years and above. We assessed diabetes distress by the seventeen-item diabetes stress (DDS17) scale and COVID-19 worries by 3 specific benchmarks: "worry about overly affected due to diabetes if infected with COVID-19", "worry about people with diabetes characterized as a risk group" and "worry about not able to manage diabetes if infected with COVID-19". A close-ended questionnaire was used in data collection. RESULTS: of 157 diabetic patients interviewed, the majority had type 2 diabetes mellitus with known complications and only 42.7% were managing COVID-19 symptoms. The participants showed moderate to high level of COVID-19 specific worry, moderate fear of isolation, and low level of diabetes-associated distress. About 33.8% of the study population expressed a sense of worry towards the pandemic. The logistic regression showed that age, employment status, and presence of other chronic diseases were significantly associated with worries about being overly affected if infected with COVID-19 due to their diabetes status. Age and sex were associated with worries about people with diabetes being characterized as a risk group and age, sex and employment status were associated with participants who were worried about not being able to manage diabetes if infected with COVID-19. CONCLUSION: the general trend indicates a sense of worry among diabetes patients during the COVID-19 pandemic which is associated with poorer psychological health. Clients' education and counseling on COVID-19 are necessary to address some of their concerns to minimize the level of anxiety and emotional stress in these individuals.


Assuntos
COVID-19/psicologia , Diabetes Mellitus Tipo 1/psicologia , Diabetes Mellitus Tipo 2/psicologia , Adulto , Fatores Etários , Ansiedade/epidemiologia , Estudos Transversais , Medo , Feminino , Gana , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Estresse Psicológico/epidemiologia , Inquéritos e Questionários , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...