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1.
Nanotechnology ; 25(9): 094008, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24522012

RESUMO

Cotton-based nanocrystalline cellulose (NCC), also known as nanopaper, one of the major sources of renewable materials, is a promising substrate and component for producing low cost fully recyclable flexible paper electronic devices and systems due to its properties (lightweight, stiffness, non-toxicity, transparency, low thermal expansion, gas impermeability and improved mechanical properties).Here, we have demonstrated for the first time a thin transparent nanopaper-based field effect transistor (FET) where NCC is simultaneously used as the substrate and as the gate dielectric layer in an 'interstrate' structure, since the device is built on both sides of the NCC films; while the active channel layer is based on oxide amorphous semiconductors, the gate electrode is based on a transparent conductive oxide.Such hybrid FETs present excellent operating characteristics such as high channel saturation mobility (>7 cm(2) V (-1) s(-1)), drain-source current on/off modulation ratio higher than 10(5), enhancement n-type operation and subthreshold gate voltage swing of 2.11 V/decade. The NCC film FET characteristics have been measured in air ambient conditions and present good stability, after two weeks of being processed, without any type of encapsulation or passivation layer. The results obtained are comparable to ones produced for conventional cellulose paper, marking this out as a promising approach for attaining high-performance disposable electronics such as paper displays, smart labels, smart packaging, RFID (radio-frequency identification) and point-of-care systems for self-analysis in bioscience applications, among others.

4.
Postgrad Med J ; 73(855): 27-31, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9039406

RESUMO

Alcohol abuse is one of the most serious problems in public health and the Wernicke-Korsakoff syndrome is one of the gravest consequences of alcoholism. The pathology is often undiagnosed in its less evident presentations, therefore an accurate diagnostic approach is a critical step in treatment planning. Treatment is based on restoration of thiamine, although this is insufficient to prevent the psychological decline of a great number of patients. The cognitive impact of the pathology is derived from the interaction of alcoholic neurotoxicity, thiamine deficiency and personal susceptibility. In this article, the literature concerning Wernicke-Korsakoff syndrome is reviewed.


Assuntos
Transtorno Amnésico Alcoólico/fisiopatologia , Doenças Metabólicas/fisiopatologia , Encefalopatia de Wernicke/fisiopatologia , Transtorno Amnésico Alcoólico/etiologia , Transtorno Amnésico Alcoólico/história , Transtorno Amnésico Alcoólico/patologia , Transtorno Amnésico Alcoólico/terapia , Alcoolismo/complicações , História do Século XIX , Humanos , Doenças Metabólicas/etiologia , Doenças Metabólicas/história , Doenças Metabólicas/patologia , Doenças Metabólicas/terapia , Prognóstico , Síndrome , Tiamina/uso terapêutico , Deficiência de Tiamina/complicações , Encefalopatia de Wernicke/etiologia , Encefalopatia de Wernicke/história , Encefalopatia de Wernicke/patologia , Encefalopatia de Wernicke/terapia
6.
Rev Saude Publica ; 28(4): 249-60, 1994 Aug.
Artigo em Português | MEDLINE | ID: mdl-7660020

RESUMO

Principal Components Analysis is a multivariate statistical technique for the purpose of examining the interdependence among variables. The main characteristic of this technique is the ability to reduce data, and it is currently used as an adjunct for the development of psychiatric research tools and the classification of psychiatric disorders. It has been applied to the study of the Factorial Structure of a Brazilian screening questionnaire, the Adult Psychiatric Morbidity Questionnaire (QMPA). The questionnaire is made up of 45 yes/no items for the identification of psychiatric symptoms and the use of psychiatric services and psychotropic drugs. The questionnaire was applied to 6.470 subjects over 15 years old in representative samples from three urban areas: Brasília, Porto Alegre and S. Paulo. Seven factors were found to explain 42.7% of the total variance: Anxiety/Somatization (eigenvalue = 3.81, 10.9%); Irritability/Depression (eigenvalue = 2.41, 6.9%); Cognitive Impairment (eigenvalue = 2.01, 5.8%); Alcoholism (eigenvalue = 1.90, 5.4%); Mood Elation (eigenvalue = 1.62, 4.6%); Hallucinatory/Delusional Disorders (eigenvalue = 1.60, 4.6%); and Drug/Therapies (eigenvalue = 1.60, 4.5%). A similar pattern of results was found when the analysis was carried out in the three places. It is suggested, on the banis of these findings, that some questions should be modified and some excluded in any future version of the questionnaire.


Assuntos
Transtornos Mentais/diagnóstico , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Inquéritos e Questionários , Adolescente , Adulto , Fatores Etários , Brasil/epidemiologia , Estudos Transversais , Análise Fatorial , Feminino , Humanos , Masculino , Transtornos Mentais/classificação , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Análise Multivariada , Estudos de Amostragem , Fatores Sexuais , População Urbana
7.
Am J Med Genet ; 51(4): 443-6, 1994 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-7943014

RESUMO

Expression of the fragile site Xq27.3 was investigated in 82 heterozygotes (58 normal and 24 mentally impaired) diagnosed by DNA analysis. EcoRI and EagI DNA digests were probed with StB12.3. This allowed the detection of the expansion of the CGG repeat of the FMR1 gene and the methylation pattern of the adjacent CpG island. Heterozygotes with delta < or = 400 bp (52/82) were all mentally normal and manifested fra(X) in less than 3% of the cells or did not express it. Unmethylated mutant alleles were always observed. About two thirds of females with delta > 500 bp (21/30) showed fra(X) frequencies above 3% (3 normal and 18 mentally impaired). Lower frequencies of fra(X) or negative results were observed in the remaining 9 females (3 normal and 6 affected). The large mutant alleles were always methylated. Therefore, while delta < or = 400 bp is always associated with negative or low expression of fra(X), larger expansions are not present exclusively in heterozygotes with high frequencies of fra(X). In 25 of 30 heterozygotes with delta > 500 bp, active and inactive normal alleles were observed. Three fra(X)-negative or low manifesting heterozygotes showed completely skewed X-inactivation, with the normal allele either active or inactive. Two females with high frequencies of fra(X) always had the normal allele inactivated. Densitometry studies showed no difference in the inactivation of the normal allele between heterozygotes who manifested fra(X) or not. Thus fra(X) expression does not seem to be influenced by X-inactivation.


Assuntos
Mecanismo Genético de Compensação de Dose , Síndrome do Cromossomo X Frágil/genética , Heterozigoto , Sequências Repetitivas de Ácido Nucleico , Sítios Frágeis do Cromossomo , Fragilidade Cromossômica , DNA/metabolismo , Sondas de DNA , Fosfatos de Dinucleosídeos/metabolismo , Feminino , Dosagem de Genes , Expressão Gênica , Humanos , Metilação , Fenótipo , Estatísticas não Paramétricas
8.
Allerg Immunol (Paris) ; 26(3): 99-101, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8185823

RESUMO

UNLABELLED: The limitations of total IgE for the screening of atopy, gave rise to in vitro multispecific IgE tests to common allergens. These should have an increased sensitivity and specificity when compared to total IgE. Previous data showed the interest of such tests in screening procedures. ALATOP is a new in vitro multispecific IgE test including common aero and food allergens, in liquid phase, for paediatric and adult population. The result is expressed only in positive/negative. The aim of the study was to determine the sensitivity, specificity, positive and negative predictive value and test efficiency, by comparing the results obtained in 266 paediatric patients (selected in our Unit based on a good correlation between clinical history and skin prick tests--SPT), between ALATOP and SPT. RESULTS: 1) Sensitivity: 89.57%; 2) Specificity: 98.06%; 3) Positive predictive value: 98.65%; 4) Negative predictive value: 85.59%; 5) Efficiency of the test: 92.86%; 6) Reproducibility of the test--average: 5.63%. Based on this results and when they are compared to single specific IgE determinations, that are assumed to be about 80% of the sensitivity of SPT, ALATOP showed excellent results, allowing its use in the screening of atopic disease.


Assuntos
Hipersensibilidade Imediata/diagnóstico , Técnicas Imunoenzimáticas , Imunoglobulina E/sangue , Programas de Rastreamento , Adolescente , Alérgenos , Especificidade de Anticorpos , Criança , Pré-Escolar , Feminino , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/imunologia , Humanos , Hipersensibilidade Imediata/sangue , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/imunologia , Lactente , Testes Intradérmicos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Hipersensibilidade Respiratória/diagnóstico , Hipersensibilidade Respiratória/imunologia , Sensibilidade e Especificidade
9.
Arch Anat Histol Embryol ; 69: 119-29, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3153557

RESUMO

From 16 to 18 days of fetal life (fl) the subfornical organ (SFO) of the rat shows diffuse acetylcholinesterase (AChE) activity. From 21 fl its definitive pattern begins to be organized and is achieved at 30 days of postnatal life (pl). This pattern is characterized by a homogeneous AChE activity in the rostral region, a ring-like distribution in the anterior medial region and a hoof-like distribution in the posterior medial region. The caudal region shows intense, uniform activity. From the rostral region two tracts emerge, ventral and dorsal, that extend to different diencephalo-telencephalic areas. From the SFO caudal region another tract emerges that extends to posterior areas.


Assuntos
Acetilcolinesterase/análise , Órgão Subfornical/enzimologia , Animais , Ratos , Ratos Endogâmicos , Órgão Subfornical/embriologia , Órgão Subfornical/crescimento & desenvolvimento
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