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1.
Chemistry ; 30(7): e202303289, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37899311

RESUMO

Formamides are important feedstocks for the manufacture of many fine chemicals. State-of-the-art synthesis of formamides relies on the use of an excess amount of reagents, giving copious waste and thus poor atom-economy. Here, we report the first example of direct synthesis of N-formamides by coupling two challenging reactions, namely reductive amination of carbonyl compounds, particularly biomass-derived aldehydes and ketones, and fixation of CO2 in the presence of H2 over a metal-organic framework supported ruthenium catalyst, Ru/MFM-300(Cr). Highly selective production of N-formamides has been observed for a wide range of carbonyl compounds. Synchrotron X-ray powder diffraction reveals the presence of strong host-guest binding interactions via hydrogen bonding and parallel-displaced π⋅⋅⋅π interactions between the catalyst and adsorbed substrates facilitating the activation of substrates and promoting selectivity to formamides. The use of multifunctional porous catalysts to integrate CO2 utilisation in the synthesis of formamide products will have a significant impact in the sustainable synthesis of feedstock chemicals.

2.
Support Care Cancer ; 32(9): 620, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39207502

RESUMO

INTRODUCTION: Head and neck cancer (HNC) care was significantly impacted by the COVID-19 pandemic. The current study aimed to explore the functional outcomes and service experiences of patients with HNC treated during and prior the COVID-19 pandemic. METHODS: Mixed methods were used to (1) retrospectively compare HNC patients' functional outcomes and allied health service usage across two time-controlled cohorts and (2) understand the experiences of HNC care using validated surveys and qualitative interviews. RESULTS: Retrospective data was extracted for 78 participants (pre-COVID-19, n = 43; during-COVID-19, n = 35), with n = 28 and n = 18 completing surveys and an interview, respectively. Significant differences were found in service modality between groups with significantly more phone and telehealth services provided during COVID-19. Service usage and functional outcomes were not significantly different between groups. During-COVID-19 participants reported being significantly less informed about their care and care was significantly less appropriate and acceptable. Thematic analysis of interviews revealed six broad themes related to communication, person-centred care, treatment logistics, care availability, safety of care, and impacts on experiences. CONCLUSIONS: This study revealed that whilst HNC care rapidly changed at the onset of COVID-19, patient access to treatment and functional outcomes did not differ significantly. Rather, factors related to the patient experience of care were discussed. Healthcare professionals working in HNC have further evidence supporting building relationships based on transparent communication and partnering with patients to overcome rapid clinical changes, as experienced during COVID-19.


Assuntos
COVID-19 , Neoplasias de Cabeça e Pescoço , Telemedicina , Humanos , COVID-19/epidemiologia , Neoplasias de Cabeça e Pescoço/terapia , Neoplasias de Cabeça e Pescoço/psicologia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Telemedicina/organização & administração , Adulto , Inquéritos e Questionários , Assistência Centrada no Paciente/organização & administração , Pesquisa Qualitativa , Idoso de 80 Anos ou mais
3.
J Am Chem Soc ; 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37023113

RESUMO

A cross-coupling reaction via the dehydrogenative route over heterogeneous solid atomic catalysts offers practical solutions toward an economical and sustainable elaboration of simple organic substrates. The current utilization of this technology is, however, hampered by limited molecular definition of many solid catalysts. Here, we report the development of Cu-M dual-atom catalysts (where M = Co, Ni, Cu, and Zn) supported on a hierarchical USY zeolite to mediate efficient dehydrogenative cross-coupling of unprotected phenols with amine partners. Over 80% isolated yields have been attained over Cu-Co-USY, which shows much superior reactivity when compared with our Cu1 and other Cu-M analogues. This amination reaction has hence involved simple and non-forceful reaction condition requirements. The superior reactivity can be attributed to (1) the specifically designed bimetallic Cu-Co active sites within the micropore for "co-adsorption-co-activation" of the reaction substrates and (2) the facile intracrystalline (meso/micropore) diffusion of the heterocyclic organic substrates. This study offers critical insights into the engineering of next-generation solid atomic catalysts with complex reaction steps.

4.
Chemistry ; 29(57): e202302057, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37449834

RESUMO

The structure and vibrational spectroscopy of centrohexaindane, 1, was investigated. This unusual molecule has a quaternary carbon atom that is coordinated to four further such quaternary carbon atoms as its core, each pair of which is bonded to an ortho-phenylene unit. Previous NMR studies have shown that the molecule has tetrahedral (Td ) symmetry in solution. The infrared and Raman spectra of chloroform and deuterochloroform solutions of 1 are completely in agreement with this conclusion, as the only modes that are visible are those allowed for Td symmetry. This is not the case in the solid state: X-ray powder diffraction indicates that the unit cell is triclinic or monoclinic with a volume in excess of 4000 Å3 . The vibrational spectroscopy is consistent with C1 site symmetry and the presence of at least two molecules in the primitive cell. It is likely that the space group is centrosymmetric.

5.
J Med Internet Res ; 25: e42111, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37159245

RESUMO

BACKGROUND: There is a dearth of high-quality evidence from digital health interventions in routine program settings in low- and middle-income countries. We previously conducted a randomized controlled trial (RCT) in Zimbabwe, demonstrating that 2-way texting (2wT) was safe and effective for follow-up after adult voluntary medical male circumcision (VMMC). OBJECTIVE: To demonstrate the replicability of 2wT, we conducted a larger RCT in both urban and rural VMMC settings in South Africa to determine whether 2wT improves adverse event (AE) ascertainment and, therefore, the quality of follow-up after VMMC while reducing health care workers' workload. METHODS: A prospective, unblinded, noninferiority RCT was conducted among adult participants who underwent VMMC with cell phones randomized in a 1:1 ratio between 2wT and control (routine care) in North West and Gauteng provinces. The 2wT participants responded to a daily SMS text message with in-person follow-up only if desired or an AE was suspected. The control group was requested to make in-person visits on postoperative days 2 and 7 as per national VMMC guidelines. All participants were asked to return on postoperative day 14 for study-specific review. Safety (cumulative AEs ≤day 14 visit) and workload (number of in-person follow-up visits) were compared. Differences in cumulative AEs were calculated between groups. Noninferiority was prespecified with a margin of -0.25%. The Manning score method was used to calculate 95% CIs. RESULTS: The study was conducted between June 7, 2021, and February 21, 2022. In total, 1084 men were enrolled (2wT: n=547, 50.5%, control: n=537, 49.5%), with near-equal proportions of rural and urban participants. Cumulative AEs were identified in 2.3% (95% CI 1.3-4.1) of 2wT participants and 1.0% (95% CI 0.4-2.3) of control participants, demonstrating noninferiority (1-sided 95% CI -0.09 to ∞). Among the 2wT participants, 11 AEs (9 moderate and 2 severe) were identified, compared with 5 AEs (all moderate) among the control participants-a nonsignificant difference in AE rates (P=.13). The 2wT participants attended 0.22 visits, and the control participants attended 1.34 visits-a significant reduction in follow-up visit workload (P<.001). The 2wT approach reduced unnecessary postoperative visits by 84.8%. Daily response rates ranged from 86% on day 3 to 74% on day 13. Among the 2wT participants, 94% (514/547) responded to ≥1 daily SMS text messages over 13 days. CONCLUSIONS: Across rural and urban contexts in South Africa, 2wT was noninferior to routine in-person visits for AE ascertainment, demonstrating 2wT safety. The 2wT approach also significantly reduced the follow-up visit workload, improving efficiency. These results strongly suggest that 2wT provides quality VMMC follow-up and should be adopted at scale. Adaptation of the 2wT telehealth approach to other acute follow-up care contexts could extend these gains beyond VMMC. TRIAL REGISTRATION: ClinicalTrials.gov NCT04327271; https://www.clinicaltrials.gov/ct2/show/NCT04327271.


Assuntos
Circuncisão Masculina , Telemedicina , Envio de Mensagens de Texto , Adulto , Humanos , Masculino , Circuncisão Masculina/efeitos adversos , Seguimentos , África do Sul , População Rural , População Urbana
6.
Br J Nurs ; 32(18): 890-896, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37830864

RESUMO

The clinical telephone helpline discussed here is a communication channel for family members and caregivers whose loved ones are in hospital. It makes full use of the effect families can have on the care experience and complements standard visiting as well as when hospital visits are restricted. The helpline helps to meet family members' health information and emotional wellbeing needs and is a reciprocal patient safety communication channel. Three main benefits have been identified. Flrst, communication between patients, relatives, communities and staff is enhanced. The helpline provides comprehensive patient clinical updates to relatives and caregivers using live digital healthcare records, and person-centred care is facilitated by patient-specific information being obtained by helpline clinicians from relatives. Second, it releases time to care. The helpline runs remotely, away from wards, enabling ward-based clinicians to prioritise direct patient care. Finally, clinical staff who are unable to work directly within wards maintain their active engagement in care provision, supporting relatives, patients and their ward-based colleagues.


Assuntos
Cuidadores , Pacientes Internados , Humanos , Cuidadores/psicologia , Hospitais , Comunicação
7.
Angew Chem Int Ed Engl ; 62(48): e202306267, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37783657

RESUMO

Deuterium labelling of organic compounds is an important process in chemistry. We report the first example of photocatalytic dehalogenative deuteration of both arylhalides and alkylhalides (40 substrates) over a metal-organic framework, MFM-300(Cr), using CD3 CN as the deuterium source at room temperature. MFM-300(Cr) catalyses high deuterium incorporation and shows excellent tolerance to various functional groups. Synchrotron X-ray powder diffraction reveals the activation of halogenated substrates via confined binding within MFM-300(Cr). In situ electron paramagnetic resonance spectroscopy confirms the formation of carbon-based radicals as intermediates and reveals the reaction pathway. This protocol removes the use of precious-metal catalysts from state-of-the-art processes based upon direct hydrogen isotope exchange and shows high photocatalytic stability, thus enabling multiple catalytic cycles.

8.
J Am Chem Soc ; 144(41): 18967-18975, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36198137

RESUMO

Increasing levels of air pollution are driving the need for the development of new processes that take "waste-to-chemicals". Herein, we report the capture and conversion under ambient conditions of a major air pollutant, NO2, using a robust metal-organic framework (MOF) material, Zr-bptc (H4bptc = 3,3',5,5'-biphenyltetracarboxylic acid), comprising {Zr6(µ3-O)4(µ3-OH)4(COO)12} clusters linked by 4-connected bptc4- ligands in an ftw topology. At 298 K, Zr-bptc shows exceptional stability and adsorption of NO2 at both low (4.9 mmol g-1 at 10 mbar) and high pressures (13.8 mmol g-1 at 1.0 bar), as measured by isotherm experiments. Dynamic breakthrough experiments have confirmed the selective retention of NO2 by Zr-bptc at low concentrations under both dry and wet conditions. The immobilized NO2 can be readily transformed into valuable nitro compounds relevant to construction, agrochemical, and pharmaceutical industries. In situ crystallographic and spectroscopic studies reveal strong binding interactions of NO2 to the {Zr6(µ3-O)4(µ3-OH)4(COO)12} cluster node. This study paves a circular pathway to enable the integration of nitrogen-based air pollutants into the production of fine chemicals.


Assuntos
Poluentes Atmosféricos , Estruturas Metalorgânicas , Dióxido de Nitrogênio , Estruturas Metalorgânicas/química , Nitrocompostos , Ligantes , Poluentes Atmosféricos/análise , Agroquímicos , Nitrogênio
9.
J Am Chem Soc ; 144(27): 11969-11974, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35775201

RESUMO

The development of materials showing rapid proton conduction with a low activation energy and stable performance over a wide temperature range is an important and challenging line of research. Here, we report confinement of sulfuric acid within porous MFM-300(Cr) to give MFM-300(Cr)·SO4(H3O)2, which exhibits a record-low activation energy of 0.04 eV, resulting in stable proton conductivity between 25 and 80 °C of >10-2 S cm-1. In situ synchrotron X-ray powder diffraction (SXPD), neutron powder diffraction (NPD), quasielastic neutron scattering (QENS), and molecular dynamics (MD) simulation reveal the pathways of proton transport and the molecular mechanism of proton diffusion within the pores. Confined sulfuric acid species together with adsorbed water molecules play a critical role in promoting the proton transfer through this robust network to afford a material in which proton conductivity is almost temperature-independent.

10.
Nat Mater ; 20(1): 84-92, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32839589

RESUMO

Ni-rich layered cathode materials are among the most promising candidates for high-energy-density Li-ion batteries, yet their degradation mechanisms are still poorly understood. We report a structure-driven degradation mechanism for NMC811 (LiNi0.8Mn0.1Co0.1O2), in which a proportion of the material exhibits a lowered accessible state of charge at the end of charging after repetitive cycling and becomes fatigued. Operando synchrotron long-duration X-ray diffraction enabled by a laser-thinned coin cell shows the emergence and growth in the concentration of this fatigued phase with cycle number. This degradation is structure driven and is not solely due to kinetic limitations or intergranular cracking: no bulk phase transformations, no increase in Li/Ni antisite mixing and no notable changes in the local structure or Li-ion mobility of the bulk are seen in aged NMCs. Instead, we propose that this degradation stems from the high interfacial lattice strain between the reconstructed surface and the bulk layered structure that develops when the latter is at states of charge above a distinct threshold of approximately 75%. This mechanism is expected to be universal in Ni-rich layered cathodes. Our findings provide fundamental insights into strategies to help mitigate this degradation process.

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