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1.
J Phys Condens Matter ; 28(10): 105901, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26885704

RESUMO

A simplified model is developed to understand the field and potential distribution through devices based on a ferroelectric film in direct contact with an electrolyte. Devices based on the ferroelectric polymer polyvinylidenefluoride-trifluoroethylene (PVDF-TrFE) were produced--in metal-ferroelectric-metal, metal-ferroelectric-dielectric-metal, and metal-ferroelectric-electrolyte-metal architectures--and used to test the model, and simulations based on the model and these fabricated devices were performed. From these simulations we find indication of progressive polarization of the films. Furthermore, the model implies that there is a relation between the separation of charge within the devices and the observed open circuit voltage. This relation is confirmed experimentally. The ability to polarize ferroelectric polymer films through aqueous electrolytes, combined with the strong correlation between the properties of the electrolyte double layer and the device potential, opens the door to a variety of new applications for ferroelectric technologies, e.g. regulation of cell culture growth and release, steering molecular self-assembly, or other large area applications requiring aqueous environments.

2.
J Mater Chem B ; 1(15): 2090-2097, 2013 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32260899

RESUMO

This paper reports on the sensing of proteins using water-gated organic field-effect transistors. As a proof-of-concept, streptavidin and avidin were used, with a biotinylated polymer as the active sensing material. The latter is a copolythiophene modified to graft biotin by peptidic coupling. After characterization of its structure, it was integrated as the channel material into transistors and its interactions with several proteins were investigated. Non-specific interactions were reduced when the polymer surface was pretreated with 1-octanol. In this case, human serum albumin had no effect on the transistor characteristics whereas avidin and streptavidin led to a decrease of the drain current.

5.
Arch Intern Med ; 171(2): 134-40, 2011 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-21263103

RESUMO

BACKGROUND: Psychosocial factors are independently associated with increased risk of cardiovascular disease (CVD) morbidity and mortality, but the effects of psychosocial factor intervention on CVD are uncertain. We performed a randomized controlled clinical trial of cognitive behavioral therapy (CBT) to measure its effects on CVD recurrence. METHODS: The study included 362 women and men 75 years or younger who were discharged from the hospital after a coronary heart disease event within the past 12 months. Patients were randomized to receive traditional care (reference group, 170 patients) or traditional care plus a CBT program (intervention group, 192 patients), focused on stress management, with 20 two-hour sessions during 1 year. Median attendance at each CBT session was 85%. Outcome variables were all-cause mortality, hospital admission for recurrent CVD, and recurrent acute myocardial infarction. RESULTS: During a mean 94 months of follow-up, the intervention group had a 41% lower rate of fatal and nonfatal first recurrent CVD events (hazard ratio [95% confidence interval], 0.59 [0.42-0.83]; P = .002), 45% fewer recurrent acute myocardial infarctions (0.55 [0.36-0.85]; P = .007), and a nonsignificant 28% lower all-cause mortality (0.72 [0.40-1.30]; P = .28) than the reference group after adjustment for other outcome-affecting variables. In the CBT group there was a strong dose-response effect between intervention group attendance and outcome. During the first 2 years of follow-up, there were no significant group differences in traditional risk factors. CONCLUSIONS: A CBT intervention program decreases the risk of recurrent CVD and recurrent acute myocardial infarction. This may have implications for secondary preventive programs in patients with coronary heart disease. Trial Registration clinicaltrials.gov Identifier: NCT00888485.


Assuntos
Terapia Cognitivo-Comportamental , Doença das Coronárias/terapia , Infarto do Miocárdio/prevenção & controle , Idoso , Consumo de Bebidas Alcoólicas/epidemiologia , Doença das Coronárias/mortalidade , Doença das Coronárias/psicologia , Feminino , Humanos , Estilo de Vida , Masculino , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/psicologia , Fatores de Risco , Fumar/epidemiologia , Suécia
6.
Arch Intern Med ; 169(9): 894-900, 2009 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-19433702

RESUMO

BACKGROUND: Patients 80 years or older are underrepresented in scientific studies. The objective of this study was to investigate the effectiveness of interventions performed by ward-based pharmacists in reducing morbidity and use of hospital care among older patients. METHODS: A randomized controlled study of patients 80 years or older was conducted at the University Hospital of Uppsala, Uppsala, Sweden. Four hundred patients were recruited consecutively between October 1, 2005, and June 30, 2006, and were randomized to control (n = 201) and intervention (n = 199) groups. The interventions were performed by ward-based pharmacists. The control group received standard care without direct involvement of pharmacists at the ward level. The primary outcome measure was the frequency of hospital visits (emergency department and readmissions [total and drug-related]) during the 12-month follow-up period. RESULTS: Three hundred sixty-eight patients (182 in the intervention group and 186 in the control group) were analyzed. For the intervention group, there was a 16% reduction in all visits to the hospital (quotient, 1.88 vs 2.24; estimate, 0.84; 95% confidence interval [CI], 0.72-0.99) and a 47% reduction in visits to the emergency department (quotient, 0.35 vs 0.66; estimate, 0.53; 95% CI, 0.37-0.75). Drug-related readmissions were reduced by 80% (quotient, 0.06 vs 0.32; estimate, 0.20; 95% CI, 0.10-0.41). After inclusion of the intervention costs, the total cost per patient in the intervention group was $230 lower than that in the control group. CONCLUSION: If implemented on a population basis, the addition of pharmacists to health care teams would lead to major reductions in morbidity and health care costs.


Assuntos
Hospitalização/estatística & dados numéricos , Equipe de Assistência ao Paciente/organização & administração , Serviço de Farmácia Hospitalar/organização & administração , Fatores Etários , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Custos Hospitalares , Hospitalização/economia , Humanos , Masculino , Morbidade , Suécia , Resultado do Tratamento
7.
BMC Cardiovasc Disord ; 7: 36, 2007 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-18031575

RESUMO

BACKGROUND: A large number of studies have reported on the psychosocial risk factor pattern prior to coronary heart disease events, but few have investigated the situation during the first year after an event, and none has been controlled. We therefore performed a case-referent study in which the prevalence of a number of psychosocial factors was evaluated. METHODS: Three hundred and forty-six coronary heart disease male and female cases no more than 75 years of age, discharged from hospital within the past 12 months, and 1038 referents from the general population, matched to the cases by age, sex and place of living, received a postal questionnaire in which information on lifestyle, psychosocial and quality of life measures were sought. RESULTS: The cases were, as expected, on sick leave to a larger extent than the referents, reported poorer fitness, poorer perceived health, fewer leisure time activities, but unexpectedly reported better social support, and more optimistic views of the future than the referents. There were no significant case-referent differences in everyday life stress, stressful life events, vital exhaustion, depressive mood, coping or life orientation test. However, women reported less favourable situations than men regarding stressful life events affecting others, vital exhaustion, depressive mood, coping, self-esteem, sleep, and symptom reporting, and female cases reported the most unfavourable situation of all groups. CONCLUSION: In this first controlled study of the situation during the first year after a CHD event disease and gender status both appeared to be determinants of psychological well-being, with gender status apparently the strongest. This may have implications for cardiac rehabilitation programmes.


Assuntos
Doença das Coronárias/psicologia , Depressão/prevenção & controle , Atenção Primária à Saúde/métodos , Qualidade de Vida/psicologia , Estresse Psicológico/psicologia , Idoso , Doença das Coronárias/complicações , Doença das Coronárias/reabilitação , Depressão/epidemiologia , Depressão/etiologia , Feminino , Seguimentos , Humanos , Masculino , Prevalência , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Inquéritos e Questionários , Suécia/epidemiologia
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