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Amaranth is a pseudocereal that contains between 50 and 60% starch, gluten-free protein, and essential amino acids. This study investigates the physicochemical changes in Amaranthus spp. grains, flour, isolated starch and nanocrystals during germination and malting. The moisture content increased from 8.9% to 41% over 2 h of soaking. The percentage of germination increased rapidly, reaching 96% after 60 h, a remarkable advantage over other cereals. The nutrient composition varied, including protein synthesis and lipid degradation. Lipid concentration decreased during malting, except for soaking, which increased by 62%. Scanning electron microscopy shows that germination does not cause morphological changes on the outer surface of the grains, while transmission electron microscopy indicates the presence of isolated nanocrystals with orthorhombic crystal structure confirmed by X-ray diffraction. The viscosity profile shows a decrease in peak viscosity. Therefore, amaranth is a potential pseudocereal that can be used as an additive in the production of fermented beverages.

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Porous silicon (PSi) on p++-type (111) silicon substrate has been fabricated by electronically etching method in hydrofluoric acid (HF) media from 5 to 110 mA/cm2 of anodizing current density. The problem of determining the optical properties of (111) PSi is board through implementing a photoacoustic (PA) technique coupled to an electrochemical cell for real-time monitoring of the formation of porous silicon thin films. PA amplitude allows the calculation of the real part of the films refractive index and porosity using the reflectance self-modulation due to the interference effect between the PSi film and the substrate that produces a periodic PA amplitude. The optical properties are studied from specular reflectance measurements fitted through genetic algorithms, transfer matrix method (TMM), and the effective medium theory, where the Maxwell Garnett (MG), Bruggeman (BR), and Looyenga (LLL) models were tested to determine the most suitable for pore geometry and compared with the in situ PA method. It was found that (111) PSi exhibit a branched pore geometry producing optical anisotropy and high scattering films.

RESUMO

We present a methodology to fabricate one-dimensional porous silicon (PSi) photonic crystals in the visible range by controlled etching and monitored by photoacoustics. Photoacoustic can record in-situ information about changes in the optical path and chemical reaction as well as in temperature, refractive index, and roughness during porous layers formation. Radiometry imaging can determine the carrier distribution of c-Si substrate that is a fundamental parameter to obtain high-quality PSi films. An electrochemical cell was calibrated through a series of single PSi layers that allows knowing the PA amplitude period, porosity, and roughness as a function of the current density. Optical properties of single layers were determined using the reflectance response in the UV-Vis range to solve the inverse problem through genetic algorithms. PhC structures were designed using the transfer matrix method and effective media approximation.Based on the growth kinetics of PSi single layers, those structures were fabricated by electrochemical etching monitored and controlled by in-situ photoacoustics.

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This research studies the crystalline compounds present in nopal (Opuntia ficus-indica) cladodes. The identification of the crystalline structures was performed using X-ray diffraction, scanning electron microscopy, mass spectrometry, and Fourier transform infrared spectroscopy. The crystalline structures identified were calcium carbonate (calcite) [CaCO3], calcium-magnesium bicarbonate [CaMg(CO3)2], magnesium oxide [MgO], calcium oxalate monohydrate [Ca(C2O4)•(H2O)], potassium peroxydiphosphate [K4P2O8] and potassium chloride [KCl]. The SEM images indicate that calcite crystals grow to dipyramidal, octahedral-like, prismatic, and flower-like structures; meanwhile, calcium-magnesium bicarbonate structures show rhombohedral exfoliation and calcium oxalate monohydrate is present in a drusenoid morphology. These calcium carbonate compounds have a great importance for humans because their bioavailability. This is the first report about the identification and structural analysis of calcium carbonate and calcium-magnesium bicarbonate in nopal cladodes, as well as the presence of magnesium oxide, potassium peroxydiphosphate and potassium chloride in these plants. The significance of the study of the inorganic components of these cactus plants is related with the increasing interest in the potential use of Opuntia as a raw material of products for the food, pharmaceutical, and cosmetic industries.

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It is essential to evaluate osteoporosis risk factors, mainly the modifiable, like the lifestyle, in Mexican women in order to prevent it, since it is a serious public health problem. We studied 805 women (35-55 years old) in the City of Queretaro, México. We obtained: personal data, family history, habits, such as smoking, alcohol, caffeine (coffee and soft drink of cola) and physical activity. Participants complete the questionnaire on 19 risk factors for osteoporosis (International Osteoporosis Foundation) one of them with risk. We evaluated: body mass index (BMI), cardiovascular risk and corporal complexion. Bone densitometry was performed in two diagnostic regions: lumbar spine and total hip and participants were classified as normal bone mass density (BMD), low BMD and osteoporosis. The prevalence of osteoporosis was 7% and of low BMD was 34%, predominantly in the lumbar region and in those with menopause. In osteoporotic women, the age was higher (51 years) and 85% menopausal women, also lower values of weight, height, BMI, waist circumference and hip than women with normal bone mass density. The significantly modifiable risk factors were: low weight, smoking and consumption of soft drink of cola with 6,5, 1,2 and 1,4 (odds ratio), respectively (p < 0.05). The significantly non-modifiable risk factors were: menopause (surgical), history of fracture and risk. It is concluded that within the modifiable risk factors for the prevention ofosteoporosis, those with the greatest impact were low weight, cigarette and soft drink of cola.

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Es indispensable evaluar los factores de riesgo en osteoporosis, principalmente los modificables, como: los estilos de vida, para prevenirla, ya que es un grave problema de salud pública. Se estudiaron 805 mujeres (35-55 años) de la ciudad de Querétaro, México. Se obtuvieron datos personales, historia familiar, hábitos como: fumar, actividad física, consumo de alcohol y de cafeína (refresco de cola y café). Las participantes completaron el cuestionario de riesgo de osteoporosis (19 factores, con uno, existe riesgo) (International Osteoporosis Foundation). Se evaluó: Índice de Masa Corporal (IMC), riesgo cardiovascular y complexión corporal (Talla/Circunferencia de muñeca). Se realizó una densitometría ósea (DXA) en dos regiones diagnósticas: columna lumbar y cadera total y las participantes se clasificaron en: densidad mineral ósea (DMO) normal, DMO baja y osteoporosis. La prevalencia de osteoporosis fue de 7% y de DMO baja fue de 34%, predominantemente en región lumbar y en aquellas con menopausia. La edad fue mayor en mujeres osteoporóticas (51 años) y el 85% menopáusicas, con valores menores de: peso, talla, IMC, circunferencia de cintura y cadera, que las normales. Los factores de riesgo modificables que aumentaron el riesgo fueron: bajo peso, fumar y consumo de refresco de cola con 6,5, 1,2 y 1,4 (razón de momios) respectivamente (p<0,05). Factores no modificables significativos: menopausia (quirúrgica), historia de fractura y riesgo de osteoporosis. Se concluye que dentro de los factores de riesgo modificables para la prevención de osteoporosis de mayor impacto en esta muestra son: bajo peso, cigarrillo y el refresco de cola.

It is essential to evaluate osteoporosis risk factors, mainly the modifiable, like the lifestyle, in Mexican women in order to prevent it, since it is a serious public health problem.We studied 805 women (35-55 years old) in the City of Queretaro, México. We obtained: personal data, family history, habits, such as smoking, alcohol, caffeine (coffee and soft drink of cola) and physical activity. Participants complete the questionnaire on 19 risk factors for osteoporosis (International Osteoporosis Foundation) one of them with risk. We evaluated: body mass index (BMI), cardiovascular risk and corporal complexion. Bone densitometry was performed in two diagnostic regions: lumbar spine and total hip and participants were classified as normal bone mass density (BMD), low BMD and osteoporosis. The prevalence of osteoporosis was 7% and of low BMD was 34%, predominantly in the lumbar region and in those with menopause. In osteoporotic women, the age was higher (51 years) and 85% menopausal women, also lower values of weight, height, BMI, waist circumference and hip than women with normal bone mass density. The significantly modifiable risk factors were: low weight, smoking and consumption of soft drink of cola with 6,5, 1,2 and 1,4 (odds ratio), respectively (p <0,05). The significantly non-modifiable risk factors were: menopause (surgical), history of fracture and risk. It is concluded that within the modifiable risk factors for the prevention of osteoporosis, those with the greatest impact were low weight, cigarette and soft drink of cola.

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La espectroscopia mediante celda fotoacústica diferencial (CFD) tiene la capacidad de medir in situ el desarrollo de diversos procesos dinámicos, entre otros la difusión de agua a través de una membrana. Mediante esta técnicase realizó el estudio de permeación de agua en huesos de rata Wistar sanos y descalcificados. Los huesos descalcificados fueron tratados mediante estimulación electromagnética a fin de evaluar la actividad celular en el hueso y, en su caso, detener la descalcificación del mismo. En este trabajo fue posible determinar la viabilidad de la CFD para la evaluación de densidad ósea indirectamente, siendo posible efectuar la evaluación in situ de permeación de agua, así como la cantidad de agua retenida en la estructura ósea al finalizar las pruebas en CFD.

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