526 research outputs found

    Wet oxidation of GeSi at (700)C

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    About 500-nm-thick films of Ge0.36Si0.64 and Ge0.28Si0.72 grown epitaxially on (100)Si have been oxidized at 700-degrees-C in wet ambient. A uniform GexSi1-xO2 oxide layer forms with a smooth interface between it and the unoxidized GexSi1-x layer below. The composition and structure of that layer remains unchanged as monitored by backscattering spectrometry or cross-sectional transmission electronic microscopy. The oxide of both samples grows as square root of oxidation duration. The parabolic rate constant increases with the Ge content and is larger than that for wet oxidation of pure Si at the same temperature. The absence of a regime of linear growth at this relatively low temperature indicates a much enhanced linear rate constant

    One-phase extraction coupled with photochemical reaction allows the in-depth lipid characterization of hempseeds by untargeted lipidomics

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    Due to their valuable nutritional content, several hemp-derived products from hempseeds have recently been placed in the market as food and food ingredients. In particular, the lipid composition of hempseeds has raised interest for their rich content in biologically active polyunsaturated fatty acids with an optimum ratio of omega-3 and omega-6 compounds. At present, however, the overall polar lipidome composition of hempseeds remains largely unknown. In the present work, an analytical platform was developed for the extraction, untargeted HRMS-based analysis, and detailed annotation of the lipid species. First, five one- and two-phase solid-liquid extraction protocols were tested and compared on a hempseed pool sample to select the method that allowed the overall highest efficiency as well as easy coupling with lipid derivatization by photochemical [2 + 2] cycloaddition with 6-azauracil. Underivatized lipids were annotated employing a data processing workflow on Compound Discoverer software that was specifically designed for polar lipidomics, whereas inspection of the MS/MS spectra of the derivatized lipids following the aza-Paternò-Büchi reaction allowed pinpointing the regiochemistry of carbon-carbon double bonds. A total of 184 lipids were annotated, i.e., 26 fatty acids and 158 phospholipids, including minor subclasses such as N-acylphosphatidylethanolamines. Once the platform was set up, the lipid extracts from nine hempseed samples from different hemp strains were characterized, with information on the regiochemistry of free and conjugated fatty acids. The overall analytical approach helped to fill a gap in the knowledge of the nutritional composition of hempseeds

    Evaluation of the carotenoid and fat-soluble vitamin profile of industrial hemp inflorescence by liquid chromatography coupled to mass spectrometry and photodiode-array detection

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    Industrial hemp (Cannabis sativa L.) is a plant matrix whose use is recently spreading for pharmaceutical and nutraceutical purposes. Detailed characterization of hemp composition is needed for future research that further exploits the beneficial effects of hemp compounds on human health. Among minor constituents, carotenoids and fat-soluble vitamins have largely been neglected to date despite carrying out several biological activities and regulatory functions. In the present paper, 22 target carotenoids and fat-soluble vitamins were analyzed in the inflorescences of seven Italian industrial hemp varieties cultivated outdoor. The analytes were extracted by cold saponification to avoid artifacts and analyzed by high-performance liquid chromatography coupled with Selected reaction monitoring mass spectrometry. Phytoene, phytofluene, and all-trans-β-carotene were the most abundant in all analyzed samples (31–55 μg g−1, 11.6–29 μg g−1, and 7.3–53 μg g−1, respectively). Besides the target analytes, liquid chromatography coupled with photodiode-array detection allowed us to tentatively identify several other carotenoids based on their retention behavior and UV–vis spectra with the support of theoretical rules and data in the literature. To the best of our knowledge, this is the first comprehensive characterization of carotenoids and fat-soluble vitamins in industrial hemp inflorescence

    Efeitos do treinamento da musculatura do assoalho pélvico sobre o parto e recém-nascido: estudo controlado randomizado

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    BACKGROUND: The use of the pelvic floor muscle training for urinary incontinence treatment is well established but little is known about its effects in labor and newborn outcomes. OBJECTIVES: To evaluate the effects of antenatal pelvic floor muscle training and strength in labor and newborn outcomes in low-income pregnant women. METHODS: This is a randomized controlled trial that recruited forty-two nulliparous healthy pregnant women aged between 18-36 years old and able to contract the pelvic floor muscles. The participants were included in the study with 20 weeks of gestational age and had their pelvic floor muscles measured by vaginal squeeze pressure. They were randomly allocated into two groups: training group and a non-intervention control group. Then, all participants had their labor and newborn outcomes evaluated through consultation of medical records by a blinded researcher. RESULTS: There were no statistically significant differences between the groups regarding gestational age at birth, type of labor, duration of the second stage of labor, total time of labor, prevalence of laceration, weight and size of the baby, and Apgar score. No correlation was observed between pelvic floor muscle strength and the second stage or the total length of labor. CONCLUSIONS: This randomized controlled trial did not find any effect of pelvic floor muscle training or pelvic floor muscle strength on labor and newborn outcomes.CONTEXTUALIZAÇÃO: O treinamento da musculatura do assoalho pélvico para tratamento da incontinência urinária é bem estabelecida, mas pouco se sabe sobre seus efeitos sobre o parto e o recém-nascido. OBJETIVOS: Avaliar se os desfechos do parto e os resultados dos recém-nascidos são influenciados pelo treinamento e força da musculatura do assoalho pélvico realizados por gestantes de baixa renda. MÉTODOS: Trata-se de um ensaio clínico randomizado que incluiu 42 gestantes nulíparas de baixo risco, com idade entre 18 e 36 anos, e que eram capazes de contrair a musculatura do assoalho pélvico. As gestantes foram incluídas no estudo com 20 semanas de idade gestacional, e realizava-se a avaliação da pressão de contração vaginal pela contração da musculatura do assoalho pélvico. Elas foram randomizadas em dois grupos: grupo de treinamento e grupo controle. Todas as voluntárias tiveram o trabalho de parto e os resultados dos recém-nascidos avaliados por meio de consulta ao prontuário por um pesquisador não envolvido com o grupo de treinamento. RESULTADOS: Não houve diferença significativa entre os grupos quanto à idade gestacional no nascimento, tipo de parto, duração da segunda fase de trabalho de parto, tempo total de trabalho de parto, prevalência da laceração perineal, peso e tamanho do bebê e índice de Apgar. Nenhuma correlação foi encontrada entre a força muscular do assoalho pélvico e a segunda fase ou a duração total do trabalho de parto. CONCLUSÕES: Este ensaio clínico randomizado não verificou qualquer influência do treinamento muscular do assoalho pélvico e da força dos músculos do assoalho pélvico sobre o trabalho de parto e os resultados do recém-nascido

    Loss of UBE3A from TH-expressing neurons suppresses GABA co-release and enhances VTA-NAc optical self-stimulation

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    Motivated reward-seeking behaviours are governed by dopaminergic ventral tegmental area projections to the nucleus accumbens. In addition to dopamine, these mesoaccumbal terminals co-release other neurotransmitters including glutamate and GABA, whose roles in regulating motivated behaviours are currently being investigated. Here we demonstrate that loss of the E3-ubiquitin ligase, UBE3A, from tyrosine hydroxylase-expressing neurons impairs mesoaccumbal, non-canonical GABA co-release and enhances reward-seeking behaviour measured by optical self-stimulation
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