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A study of the effect of the thin layer of free water in corn kernels on the emissivity and interference in the mid infrared range was performed. The emissivity was measured through thermal infrared images by direct method for 8 days, allowing observance that the thickness of free water modifies the quantity of emitted energy and emissivity; however, in the first days when the layer of free water is not optically thick the interference caused by the thin film of superficial water averts a correct measurement of the emissivity. This interference effect was studied and characterized, finding that the number of oscillations in the energy of the grain, observed and counted in a very small area, can be used to compute the thickness of the free water layer contained between the endosperm and the pericarp of the grain.
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Objective: The prevalence of diabetes mellitus in Mexico is very high. This study aimed to compare the risk factors of diabetes mellitus in Mexican adults in 2003 and in 2014. Methods: This study had a repeated cross-sectional design. Data from the World Health Organization (WHO) Study on global AGEing and adult health (SAGE) from Mexico (Wave 0, 2003, and Wave 2, 2014) were compared. Self-reported diabetes mellitus (outcome) was evaluated with the yes/no question: "Have you ever been diagnosed with diabetes mellitus (high blood sugar)?" Bivariate analyses and multivariable logistic regression analyses adjusted for potential risk factors were conducted. Results: In 11 years (2003-2014), the prevalence of self-reported diabetes mellitus in Mexican adults increased by 2.6 times in those younger than 50 years (2003: 2.1%; 2014: 5.5%) and by 1.9 times in those ≥50 years (2003: 12.7%; 2014: 24.2%). In 2003, the risk factors associated with diabetes mellitus were female sex (OR 1.344, 95% CI 1.176-1.536), age ≥50 years (OR 6.734, 95% CI 5.843-7.760), being overweight (OR 1.359, 95% CI 1.175-1.571), obesity (OR 1.871, 95% CI 1.583-2.211), and lower physical activity of <600 MET-minutes/week (OR 1.349, 95% CI 1.117-1.630). In 2014, the exposure characteristics significantly associated with diabetes mellitus were female sex (OR 1.244, 95% CI 1.025-1.511), older age ≥50 years (OR 4.608, 95% CI 3.260-6.515), being overweight (OR 1.649, 95% CI 1.305-2.083), obesity (OR 1.778, 95% CI 1.398-2.261), and in those who had not attended/completed primary school (OR 1.360, 95% CI 1.042-1.773). Conclusion: The prevalence of diabetes mellitus in Mexico significantly increased from 2003 to 2014. Female sex, age older than 50 years, and being overweight or obese were significant risk factors in both 2003 and 2014. Not having completed primary school was a new significant risk factor in 2014. Public health policies and strategies should prioritize decreasing the high levels of overweight and obesity, and improve health literacy in Mexico.
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A comparative single-evaluation cross-sectional study was performed to evaluate cognitive damage in post-COVID-19 patients. The psychophysics tests of Two-Alternative Forced Choice (2AFC) and Simple Reaction Time (SRT), under a designed virtual environment, were used to evaluate the cognitive processes of decision-making, visual attention, and information processing speed. The population under study consisted of 147 individuals, 38 controls, and 109 post-COVID patients. During the 2AFC test, an Emotiv EPOC+® headset was used to obtain EEG signals to evaluate their Focus, Interest, and Engagement metrics. Results indicate that compared to healthy patients or recovered patients from mild-moderate COVID-19 infection, patients who recovered from a severe-critical COVID infection showed a poor performance in different cognitive tests: decision-making tasks required higher visual sensitivity (p = 0.002), Focus (p = 0.01) and information processing speed (p < 0.001). These results signal that the damage caused by the coronavirus on the central nervous and visual systems significantly reduces the cognitive processes capabilities, resulting in a prevalent deficit of 42.42% in information processing speed for mild-moderate cases, 46.15% for decision-making based on visual sensitivity, and 62.16% in information processing speed for severe-critical cases. A psychological follow-up for patients recovering from COVID-19 is recommended based on our findings.
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Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a neurodegenerative disease due to mutations in TUBB4A. Patients suffer from extrapyramidal movements, spasticity, ataxia, and cognitive deficits. Magnetic resonance imaging features are hypomyelination and atrophy of the striatum and cerebellum. A correlation between the mutations and their cellular, tissue and organic effects is largely missing. The effects of these mutations on sensory functions have not been described so far. We have previously reported a rat carrying a TUBB4A (A302T) mutation and sharing most of the clinical and radiological signs with H-ABC patients. Here, for the first time, we did a comparative study of the hearing function in an H-ABC patient and in this mutant model. By analyzing hearing function, we found that there are no significant differences in the auditory brainstem response (ABR) thresholds between mutant rats and WT controls. Nevertheless, ABRs show longer latencies in central waves (II-IV) that in some cases disappear when compared to WT. The patient also shows abnormal AEPs presenting only Waves I and II. Distortion product of otoacoustic emissions and immunohistochemistry in the rat show that the peripheral hearing function and morphology of the organ of Corti are normal. We conclude that the tubulin mutation severely impairs the central hearing pathway most probably by progressive central white matter degeneration. Hearing function might be affected in a significant fraction of patients with H-ABC; therefore, screening for auditory function should be done on patients with tubulinopathies to evaluate hearing support therapies.
Assuntos
Deficiências do Desenvolvimento/genética , Distúrbios Distônicos/genética , Perda Auditiva Neurossensorial/genética , Tubulina (Proteína)/deficiência , Substituição de Aminoácidos , Animais , Percepção Auditiva , Pré-Escolar , Núcleo Coclear/patologia , Doenças Desmielinizantes/genética , Modelos Animais de Doenças , Orelha Interna/fisiopatologia , Potenciais Evocados Auditivos , Feminino , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Colículos Inferiores/patologia , Masculino , Mutação de Sentido Incorreto , Bainha de Mielina/patologia , Mutação Puntual , Ratos , Ratos Mutantes , Ratos Sprague-Dawley , Tubulina (Proteína)/genéticaRESUMO
To study the radiation emitted by the human skin, the emissivity of its surface must be known. We present a new approach to measure the emissivity of the human skin in vivo. Our method is based on the calculation of the difference of two infrared images: one acquired before projecting a CO(2) laser beam on the surface of the skin and the other after such projection. The difference image contains the radiation reflected by the skin, which is used to calculate the emissivity, making use of Kirchhoff's law and the Helmholtz reciprocity relation. With our method, noncontact measurements are achieved, and the determination of the skin temperature is not needed, which has been an inconvenience for other methods. We show that it is possible to make determinations of the emissivity at specific wavelengths. Last, our results confirm that the human skin obeys Lambert's law of diffuse reflection and that it behaves almost like a blackbody at a wavelength of 10.6 microm.
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Algoritmos , Temperatura Cutânea/fisiologia , Pele/efeitos da radiação , Espectrofotometria Infravermelho/métodos , Termografia/métodos , Relação Dose-Resposta à Radiação , Raios Infravermelhos , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
A noninvasive, quick, reliable, and relatively cheap procedure for the diagnosis of onychomycosis is put forward. It is known that a nail may show an abnormal appearance, although only 50% of all the nails having such an appearance may owe it to the presence of onychomycosis; hence, adequate diagnosis of nail disease is needed for appropriate prescription of medication and treatment of the nail. In order to contribute to the process of improvement in the diagnosis, a procedure based on the analysis of medium-range infrared images is presented in which it is possible to observe energy changes mostly due to the changes in emissivity of the nail. As a nail is more affected by onychomycosis, such changes become more intense. Also, it was found that a nail without onychomycosis has a lower temperature than toe skin, but has a higher emission of energy. Fifty percent of the ailments that may a cause a fingernail or toenail to have an abnormal appearance are not considered in the present work.