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1.
BMC Med Inform Decis Mak ; 15: 13, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25880757

RESUMO

BACKGROUND: Decision boxes (DBoxes) are two-page evidence summaries to prepare clinicians for shared decision making (SDM). We sought to assess the feasibility of a clustered Randomized Controlled Trial (RCT) to evaluate their impact. METHODS: A convenience sample of clinicians (nurses, physicians and residents) from six primary healthcare clinics who received eight DBoxes and rated their interest in the topic and satisfaction. After consultations, their patients rated their involvement in decision-making processes (SDM-Q-9 instrument). We measured clinic and clinician recruitment rates, questionnaire completion rates, patient eligibility rates, and estimated the RCT needed sample size. RESULTS: Among the 20 family medicine clinics invited to participate in this study, four agreed to participate, giving an overall recruitment rate of 20%. Of 148 clinicians invited to the study, 93 participated (63%). Clinicians rated an interest in the topics ranging 6.4-8.2 out of 10 (with 10 highest) and a satisfaction with DBoxes of 4 or 5 out of 5 (with 5 highest) for 81% DBoxes. For the future RCT, we estimated that a sample size of 320 patients would allow detecting a 9% mean difference in the SDM-Q-9 ratings between our two arms (0.02 ICC; 0.05 significance level; 80% power). CONCLUSIONS: Clinicians' recruitment and questionnaire completion rates support the feasibility of the planned RCT. The level of interest of participants for the DBox topics, and their level of satisfaction with the Dboxes demonstrate the acceptability of the intervention. Processes to recruit clinics and patients should be optimized.


Assuntos
Tomada de Decisões , Sistemas de Apoio a Decisões Clínicas , Técnicas de Apoio para a Decisão , Estudos de Avaliação como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Estudos de Viabilidade , Humanos
2.
J Phys Chem B ; 113(2): 567-73, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19086802

RESUMO

We present here the effects of geometrically constrained environments on the proton transfer reaction of 4-methyl 2,6-diformyl phenol (MFOH) both in the ground and excited states by employing steady-state and time-resolved fluorescence spectroscopy having picosecond and femtosecond resolutions. The nanometer-sized water pools formed in the ternary microemulsion of n-heptane-aerosol OT-water promote reprotonation of the probe. As we go on increasing the water content up to a certain value in the ground state whereas deprotonation is favored in the excited state. The emission intensity has a complex behavior as the water content is changed in the system. The lower fluidity of confined water within the reverse micelle with respect to the normal bulk water alters the related dynamics of the H-bonded network. These observations are rationalized on the basis of altered ionic water activity in the confined surroundings, i.e., on dielectric constant, ionic mobility, pH, and the favorable orientation of dipoles in the medium. Our observations might be helpful to infer about the characteristics of nanoreactors, which often mimic many biological hydrophilic pockets.


Assuntos
Nanotecnologia , Prótons , Cresóis , Micelas , Estrutura Molecular , Nanoestruturas/química , Espectrofotometria , Fatores de Tempo
3.
J Phys Chem A ; 110(47): 12743-51, 2006 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-17125287

RESUMO

We report here on the steady-state and time-resolved fluorescence studies on proton-transfer (PT) reaction of 4-methyl 2,6-diformyl phenol (MFOH) in confined nanocavities in three solvents, dimethyl sulfoxide (DMSO), dimethyl formamide (DMF), and water. Though DMSO and DMF individually interact with MFOH in a similar fashion, their modes of interaction get significantly modified in the presence of cyclodextrin (CD) nanocages. In DMSO, in the ground state, the solvated molecular anion of MFOH forms 1:1 inclusion complex with beta- or gamma-CD and attains greater stability compared to the normal form. In DMF, the solvated molecular anion gets converted to the H-bonded complex within the CD cavity resulting in a 50-nm blue shift in the absorption spectra. In the excited state, the anionic species gets more stabilized in DMSO while in DMF it is significantly destabilized in the presence of CDs. However, in case of water, MFOH gets trapped inside the water cages so that the CDs fail to complex with it effectively. There are also no changes in the excited-state lifetimes in water in the presence of CDs, but in case of DMSO and DMF, because of restricted rotation of the formyl group within the CD cavity, the contribution of the shorter lifetime components reduce significantly increasing the larger components. Some theoretical calculations at the AM1 level of approximation have also been carried out to demonstrate how the dipolar nature of the solvent influences excited-state PT in confined media.

4.
Artigo em Inglês | MEDLINE | ID: mdl-15741132

RESUMO

Proton transfer processes of 4-hydroxy-3-formyl benzoic acid (HFBA) have been studied in a number of different protic solvents by means of absorption, emission and nanosecond transient spectroscopy at room temperature and 77K. Intermolecular interaction occurs in polar protic solvents only in presence of a base in the ground state whereas in the excited state, intermolecular complex formation and proton transfer occurs even in pure protic solvents. The dianion is detected in water, methanol, ethanol and TFE in presence of base. HFBA shows phosphorescence in pure ethanol at 77K. The occurrence of phosphorescence is due to rupture of the intramolecular bond and rotation of the formyl group. We have calculated quantum yields of fluorescence and also estimated decay rates from nanosecond measurements. The energetics of the ground and excited state proton transfer in HFBA have been investigated at the AM1 level of approximation. The ground singlet is predicted to have a large activation barrier on the proton transfer path, while the barrier height is much lower on the corresponding excited singlet surface.


Assuntos
Ácido Benzoico/química , Prótons , Transferência de Energia , Estrutura Molecular , Solventes , Espectrometria de Fluorescência , Temperatura
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