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31.
During childhood and adolescence, eating habits become established which are instrumental in determining eating behavior later in life. Various authors have described the acculturation of the Mapuche people toward Western culture. The objective of this study was to analyze the eating characteristics of indigenous and non-indigenous adolescent girls in the Araucania Region of Chile. A cross-sectional design was used with a probabilistic sample of 281 adolescents comprised of 139 indigenous and 142 non-indigenous girls attending 168 elementary schools. A modified food frequency questionnaire was applied, designed to obtain information about eating habits and consumption of Mapuche foods. The eating schedules are similar in both ethnic groups, with dinner being the meal that is least consumed. Total snack consumption per week has a mean of 7 with an interquartile range (IQR) of 5 to 10 without any differences between ethnic groups; of these snacks, only 2 were healthy (IQR = 1 to 3). The indigenous girls had a higher probability of consumption of native foods including mote (boiled wheat) (OR = 2.00; IC = 0.93-4.29), muday (fermented cereal alcohol) (OR = 3.45; IC = 1.90-6.27), and yuyo (field mustard) (OR = 4.40; IC = 2.06-9.39). The study's conclusion is that the the eating habits and behavior of indigenous adolescents are similar to those of non-indigenous girls, though the former still consume more indigenous foods.  相似文献   
32.
Aminophenoxazinone dyes with variable water solubilities were assayed for the first time in a live‐cell imaging application. Among a library of ten sulfonylated chromophores, one compound gave excellent results as an endocytic marker, showing a precise subcellular distribution. The compound was compared to four commercial vital tracers, including Lucifer Yellow. The first laccase‐mediated regioselective synthesis of a diphosphorylated 2‐aminophenoxazinone dye was also described. This compound, water‐soluble at 10?2 M , displayed modest fluorescence properties and the ability to complex Mg2+ and Ca2+ cations, therefore giving fluorescence quenching.  相似文献   
33.
Agelaia-MPI and protonectin are antimicrobial peptides isolated from the wasp Parachartergus fraternus that show antimicrobial and neuroactive activities. Previously, two analogues of these peptides, neuroVAL and protonectin-F, were designed to reduce nonspecific toxicity and improve potency. Here, the three-dimensional structures of neuroVAL, protonectin and protonectin-F were determined by using circular dichroism and NMR spectroscopy. Antibacterial, antifungal, cytotoxic and hemolytic activities were tested for the parent peptides and analogues. All peptides showed moderate antimicrobial activity against Gram-positive bacteria, with agelaia-MPI being the most active. Protonectin and protonectin-F were found to be toxic to cancerous and noncancerous cell lines. Internalization experiments revealed that these peptides accumulate inside both cell types. By contrast, neuroVAL was nontoxic to all tested cells and was able to enter cells without accumulating. In summary, neuroVAL has potential as a nontoxic cell-penetrating peptide, while protonectin-F needs further modification to realize its potential as an antitumor peptide.  相似文献   
34.
During pregnancy, freely floating placental villi are adapted to fluid shear stress due to placental perfusion with maternal plasma and blood. In vitro culture of placental villous explants is widely performed under static conditions, hoping the conditions may represent the in utero environment. However, static placental villous explant culture dramatically differs from the in vivo situation. Thus, we established a flow culture system for placental villous explants and compared commonly used static cultured tissue to flow cultured tissue using transmission and scanning electron microscopy, immunohistochemistry, and lactate dehydrogenase (LDH) and human chorionic gonadotropin (hCG) measurements. The data revealed a better structural and biochemical integrity of flow cultured tissue compared to static cultured tissue. Thus, this new flow system can be used to simulate the blood flow from the mother to the placenta and back in the most native-like in vitro system so far and thus can enable novel study designs.  相似文献   
35.
As life expectancy has increased, particularly in developed countries, due to medical advances and increased prosperity, age-related neurological diseases and mental health disorders have become more prevalent health issues, reducing the well-being and quality of life of sufferers and their families. In recent decades, due to reduced work-related levels of physical activity, and key research insights, prescribing adequate exercise has become an innovative strategy to prevent or delay the onset of these pathologies and has been demonstrated to have therapeutic benefits when used as a sole or combination treatment. Recent evidence suggests that the beneficial effects of exercise on the brain are related to several underlying mechanisms related to muscle–brain, liver–brain and gut–brain crosstalk. Therefore, this review aims to summarize the most relevant current knowledge of the impact of exercise on mood disorders and neurodegenerative diseases, and to highlight the established and potential underlying mechanisms involved in exercise–brain communication and their benefits for physiology and brain function.  相似文献   
36.
To reduce the computational cost of turbulent combustion simulations with a detailed chemical mechanism, it is useful to find a low-dimensional manifold in composition space. Most previous low-dimensional manifolds in turbulent combustion are based on the governing conservation equations or thermochemistry and their application involves certain assumptions. On the other hand, empirical low-dimensional manifolds (ELDMs) are constructed based on samples of the compositions observed in experiments or in direct numerical simulation (DNS). Plane and curved ELDMs can be obtained using principal component analysis (PCA) and multivariate adaptive spline regression (MARS), respectively. The framework for ELDMs based on the represented compositions and principal components is considered in this study, where the represented compositions are selected from the PCA results.  相似文献   
37.
Electrospray ionization liquid chromatography/tandem mass spectrometry was used to identify the fatty acid and triacylglycerol (TAG) composition of pequi (Caryocar brasiliensis Camb.) oil. The fatty acid composition was relatively simple; the oil contained approximately 442 and 517 g kg?1 of palmitic and oleic acids respectively. Linoleic and stearic acids were found in much smaller amounts. The TAG composition of pequi oil is also relatively simple with trioleoyl glycerol (OOO, 56 g kg?1), palmitoyl dioleoyl glycerol (POO, 466 g kg?1) and dipalmitoyl oleoyl glycerol (POP, 452 g kg?1) comprising 974 g kg?1 of the total. Dioleoyl stearoyl glycerol (OOS) was found in small amounts (5.2 g kg?1). All TAGs were identified via sodium adduct molecular ions [M + Na]+, where M is the TAG in question. Tandem mass analysis provided a very useful fragmentation pattern showing both sodium adduct diacylglycerol ions and diacylglycerol ions with the neutral loss of fatty acid residues. Copyright © 2005 Society of Chemical Industry  相似文献   
38.
A systematic approach was developed to derive non-stiff reduced mechanisms for direct numerical simulations (DNS) with explicit integration solvers. The stiffness reduction was achieved through on-the-fly elimination of short time-scales induced by two features of fast chemical reactivity, namely quasi-steady-state (QSS) species and partial-equilibrium (PE) reactions. The sparse algebraic equations resulting from QSS and PE approximations were utilized such that the efficiency of the dynamic stiffness reduction is high compared with general methods of time-scale reduction based on Jacobian decomposition. Using the dimension reduction strategies developed in our previous work, a reduced mechanism with 52 species was first derived from a detailed mechanism with 561 species. The reduced mechanism was validated for ignition and extinction applications over the parameter range of equivalence ratio between 0.5 and 1.5, pressure between 10 and 50 atm, and initial temperature between 700 and 1600 K for ignition, and worst-case errors of approximately 30% were observed. The reduced mechanism with dynamic stiffness removal was then applied in homogeneous and 1-D ignition applications, as well as a 2-D direct numerical simulation of ignition with temperature inhomogeneities at constant volume with integration time-steps of 5-10 ns. The integration was numerically stable and good accuracy was achieved.  相似文献   
39.
Traditional input indicators of research performance, such as research funding, number of active scientists, and international collaborations, have been widely used to assess countries’ publication output. However, while publication in today’s English-only research world requires sound research in readable English, English proficiency may be a problem for the productivity of non-native English-speaking (NNES) countries. Data provided by the Brazilian National Research Council (CNPq) containing the academic profile of 51,223 Brazilian researchers show a correlation between English proficiency and publication output. According to our results, traditional input indicators may fall short of providing an accurate representation of the research performance of NNES developing countries.  相似文献   
40.
This article is a discussion of how to measure urban inequality using the results of large household samples. It has two aims. The first is to de-mystify the methods of measuring earnings inequality by discussing their logic and their results in plain language that is suitable for a non-specialist audience. The second is to persuade the reader that such surveys can be suitable for measuring income derived from all kinds of livelihood strategies, including informal sector activities. The results show persistently high levels of inequality over time among income earners on the Copperbelt. Disaggregation of the employed workforce by major occupational groups reveals increasingly more elementary and middle-income workers than higher income managers, professionals, and technicians. This pattern differs by gender, however, with only women experiencing a marked increase in low-skill, low-wage employment.  相似文献   
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