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1.
ChemSusChem ; 15(21): e202201317, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36083105

RESUMO

In this study, dinuclear cobalt complexes (1 and 2) featuring bis(benzimidazole)pyrazolide-type ligands (H2 L and Me2 L) were prepared and evaluated as molecular electrocatalysts for water oxidation. Notably, 1 bearing a non-innocent ligand (H2 L) displayed faster catalytic turnover than 2 under alkaline conditions, and the base dependence of water oxidation and kinetic isotope effect analysis indicated that the reaction mediated by 1 proceeded by a different mechanism relative to 2. Spectroelectrochemical, cold-spray ionization mass spectrometric and computational studies found that double deprotonation of 1 under alkaline conditions cathodically shifted the catalysis-initiating potential and further altered the turnover-limiting step from nucleophilic water attack on (H2 L)CoIII 2 (superoxo) to deprotonation of (L)CoIII 2 (OH)2 . The rate-overpotential analysis and catalytic Tafel plots showed that 1 exhibited a significantly higher rate than previously reported Ru-based dinuclear electrocatalysts at similar overpotentials. These observations suggest that using non-innocent ligands is a valuable strategy for designing effective metal-based molecular water oxidation catalysts.


Assuntos
Cobalto , Água , Cobalto/química , Ligantes , Água/química , Oxirredução , Catálise
2.
Am J Occup Ther ; 76(4)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35671508

RESUMO

IMPORTANCE: People with chronic mental illness (CMI) are at high risk of poor cardiorespiratory fitness as a result of sedentary behavior and physical inactivity. Occupational therapy practitioners play a key role as advocates for positive lifestyle change for people with CMI. OBJECTIVE: To determine the relationships between occupational therapy activities and cardiorespiratory fitness among inpatients with CMI. DESIGN: This retrospective research included three phases: descriptive cohort, case-control, and cross-sectional studies. SETTING: Psychiatric inpatient facility. PARTICIPANTS: Inpatients with CMI, ages 18 to 65 yr (N = 325). OUTCOMES AND MEASURES: Data were collected over a 12-mo period. Each daily occupational therapy activity performed by participants was converted to energy expenditure (in kcal). Cardiorespiratory fitness was measured by means of the 3-Minute Step Test. RESULTS: After daily occupational therapy activities, significantly more participants increased cardiorespiratory fitness than declined (McNemar χ2 [1] = 29.18, p < .05). Prevocational activities and moderate- to high-intensity exercises met the optimal energy expenditure level (>352 kcal) necessary to achieve an increase in cardiorespiratory fitness. CONCLUSIONS AND RELEVANCE: Occupational therapists in psychiatric inpatient settings should prescribe individualized occupation-based or physical activities that meet the optimal daily energy expenditure for each client to improve their cardiorespiratory function. What This Article Adds: This study is one of the first attempts to explore cardiorespiratory fitness outcomes after daily occupational therapy activities for people with CMI. Physical benefits unfolded throughout psychiatric care, echoing the profession's stance on holistic practice.


Assuntos
Aptidão Cardiorrespiratória , Transtornos Mentais , Terapia Ocupacional , Adolescente , Adulto , Idoso , Doença Crônica , Estudos Transversais , Humanos , Pacientes Internados , Pessoa de Meia-Idade , Aptidão Física , Estudos Retrospectivos , Adulto Jovem
3.
BMC Psychiatry ; 22(1): 87, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35120468

RESUMO

BACKGROUND: Walking is the fundamental component of taking steps and is the main form of physical activity among individuals with schizophrenia; it also offers a range of health benefits. This study aimed to examine the associations between daily steps and cognitive function and further explored how many steps were related to better cognitive function among inpatients with schizophrenia. METHODS: Inpatients with schizophrenia were recruited from long-stay psychiatric wards across two hospitals (n=199 at site 1 and n=195 at site 2). Daily steps were collected with an accelerometer for 7 days. Four cognitive domains (attention, processing speed, reaction time, and motor speed) were tested at site 1, and two cognitive domains (attention and processing speed) were tested at site 2. The associations of daily steps and levels of steps/day with cognitive function were tested using multivariable linear regressions separated by site. Covariates included demographic variables, weight status, metabolic parameters, and clinical state. RESULTS: Participants took an average of 7445 (±3442) steps/day. More steps were related to better attention, processing speed, reaction time, and motor speed after multivariable adjustments. Compared with participants taking <5000 steps/day, those taking ≥5000 steps/day showed significantly better processing speed. Participants taking ≥7500 steps/day were associated with better attention, better reaction time, and better motor speed than those taking <5000 steps/day. CONCLUSION: Daily steps are associated with better cognitive function among inpatients with schizophrenia. The optimal benefit for cognitive function among this clinical population is achieving 7500 steps/day or more.


Assuntos
Esquizofrenia , Cognição , Exercício Físico , Humanos , Pacientes Internados , Esquizofrenia/complicações , Caminhada
4.
ChemSusChem ; 15(5): e202102378, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-34881515

RESUMO

The utilization of earth-abundant low-toxicity metal ions in the construction of highly active and efficient molecular catalysts promoting the water oxidation reaction is important for developing a sustainable artificial energy cycle. However, the kinetic and thermodynamic properties of the currently available molecular water oxidation catalysts (MWOCs) have not been comprehensively investigated. This Review summarizes the current status of MWOCs based on first-row transition metals in terms of their turnover frequency (TOF, a kinetic property) and overpotential (η, a thermodynamic property) and uses the relationship between log(TOF) and η to assess catalytic performance. Furthermore, the effects of the same ligand classes on these MWOCs are discussed in terms of TOF and η, and vice versa. The collective analysis of these relationships provides a metric for the direct comparison of catalyst systems and identifying factors crucial for catalyst design.


Assuntos
Complexos de Coordenação , Elementos de Transição , Catálise , Oxirredução , Água
5.
J Hazard Mater ; 407: 124392, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33162242

RESUMO

In this study, a sub-class of microporous crystalline metal organic frameworks (MOFs) with zeolite-like configurations, i.e., zeolitic imidazolate frameworks of single node ZIF-67 and binary nodes ZIF-Co/Zn are used as the supports to develop Cu nanoparticles based nanocatalysts. Their catalytic activities are comparatively evaluated where Cu(x)@ZIF-Co/Zn exhibits better performances than Cu(x)@ZIF-67 in the reduction of synthetic dyes and nitroarenes. For instance, the Cu(0.25)@ZIF-Co/Zn catalyst shows an excellent reaction rate of 2.088 × 10-2 s-1 and an outstanding activity of 104.4 s-1gcat-1 for the reduction of methyl orange. The same catalyst also performs an exceptional catalytic activity in the hydrogenation of p-nitrophenol to p-aminophenol with the activity of 216.5 s-1gcat-1. A synergistic role of unique electronic properties rising from the direct contact of Cu NPs with the bimetallic nodes ZIF-Co/Zn, higher surface area of support, appropriate Cu loading and maintainable microporous frameworks with higher thermal and hydrolytic stability collectively enhances the catalytic activity of Cu(x)@ZIF-Co/Zn. Moreover, this catalyst shows excellent stability and recyclability, which can retain high conversion after reuse for 10 cycles.

6.
Org Lett ; 13(11): 2826-9, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21534612

RESUMO

In electrochemical oxidations, the second oxidation potential of phenylenediamines (PD) varies because of hydrogen-bonding formation for PD(+•) with pyridines. A linear relationship was obtained for the potential shift as a function of pK(a) of the protonated pyridines and potential inversion could be observed. The oxidized PD(+•) could also form hydrogen bonding with alcohols and the shift of potential exhibits a different pattern.

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