508 research outputs found
Transformation, Identification, and Inversion of Goldberg-Coxeter Fullerenes
It is difficult to identify a G-C fullerene directly from its dimensions as
its lattice is not proportional to that of its archetype in general, although
they have the same three-dimensional shape. In this paper, the area scale
factor of a G-C fullerene is proved to be an integer, which can be calculated
from its dimensions. All the G-C transformations are k-inflations that can be
easily identified and inversed, primary transformations whose area scale
factors are prime numbers, or composite transformations whose area scale
factors are the product of those of its sub-transformations. As the result, a
method to identify any G-C fullerenes according to the area scale factor was
presented.Comment: 6 pages, 3 figure
Statistical characterization and reconstruction of heterogeneous microstructures using deep neural network
Heterogeneous materials, whether natural or artificial, are usually composed of distinct constituents present in complex microstructures with discontinuous, irregular and hierarchical characteristics. For many heterogeneous materials, such as porous media and composites, the microstructural features are of fundamental importance for their macroscopic properties. This paper presents a novel method to statistically characterize and reconstruct random microstructures through a deep neural network (DNN) model, which can be used to study the microstructure–property relationships. In our method, the digital microstructure image is assumed to be a stationary Markov random field (MRF), and local patterns covering the basic morphological features are collected to train a DNN model, after which statistically equivalent samples can be generated through a DNN-guided reconstruction procedure. Furthermore, to overcome the short-distance limitation associated with the MRF assumption, a multi-level approach is developed to preserve the long-distance morphological features of heterogeneous microstructures. A large number of tests have been conducted to compare the reconstructed and target microstructures in both morphological characteristics and physical properties, and good agreements are observed in all test cases. The proposed method is efficient, accurate, versatile, and especially beneficial to the statistical reconstruction of 2D/3D microstructures with long-distance correlations
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The Influence of Immigrant Generation on Obesity Among Asian Americans in California from 2013 to 2014
Objectives We aimed to examine the association between immigrant generation and obesity among Californian adults and Asian Americans. Results Overall, 23.3% of the Asian population was obese, and 40.0% was overweight. The percentage of 1st, 2nd, and 3rd generation were 72.7%, 22.6%, and 4.6%, respectively. Overall, 1st generation of Asians had lower odds of being obese compared to Whites (OR = 0.34, 95%CI = 0.26–0.45). Multiple logistic regression analyses showed that overall, 2nd generation (OR = 1.69, 95%CI = 1.10–2.60) and 3rd generation (OR = 2.33, 95%CI = 1.29–4.22) Asians had higher odds of being obese compared to 1st generation Asians. Among Chinese, compared to the 1st generation, the 3rd generation had increased likelihood of being obese (OR = 6.29, 95%CI = 2.38–16.6). Conclusion Compared to Whites, Hispanics, and Blacks, Asian immigrants are less likely to be obese. Among Asians, 2nd and 3rd generations were more likely to be obese compared to 1st generation. The obesity rate seems to increase the longer Asian immigrants remain in the U.S
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Geographic Differences in Obesity Prevalence and Its Risk Factors Among Asian Americans: Findings from the 2013–2014 California Health Interview Survey
Geography disparities exist in obesity and obesity related conditions. This study aimed to examine the geographic differences in obesity prevalence and its risk factors among Asian Americans in California. Data (n = 4,000) from the 2013–2014 California Health Interview Survey were used. Obesity (≥27.5 kg/m2) was defined according to the World Health Organization Asian body mass index cut points in Asian groups. Results suggest that 66.5% of Asians lived in urban areas. Among Asian adults, obesity prevalence was highest in Filipinos (33.8%) and lowest in Koreans (12.8%). Compared to rural Vietnamese, obesity prevalence was higher for urban Vietnamese (8.3% vs. 20.2%, p = 0.0318). Weighted multiple logistic regression analyses showed that being 45–64 years (vs. 65 years or above), being Japanese, Filipino, or other Asians (vs. Chinese) were associated with a higher odds of obesity among urban residents; whereas being 18–44 years and being 45–64 years (vs. 65 years or older), being male, having high school education (vs. having graduate education) were associated with a higher odds of obesity among rural residents. Being Vietnamese (vs. Chinese) was associated with 64% decreased odds of obesity only among rural residents (95% confidence interval = 0.14–0.94). The findings show geography disparities in obesity among Asians in California
Ethnic Group Differences in Obesity in Asian Americans in California, 2013–2014
Background: Obesity has been generally understudied in Asian Americans. It is important to identify subgroups of Asian Americans at high risk of obesity to help develop targeted interventions for those subgroups. This study aimed to examine the disparities in obesity among Asians (i.e., Chinese, Filipino, Japanese, Korean, and Vietnamese) living in California. Methods: A sample of Adult Americans in California (n = 47,970) including Asian American adults (n = 3810) aged 18 years or older were obtained from the 2013–2014 California Health Interview Survey (the U.S. nation’s largest state cross-sectional health survey). Body mass index was calculated using self-reported height and weight. Weight status was determined using the WHO Asian BMI cut points in 4 categories: \u3c 18.5 kg/m2 (underweight), 18.5–22.9 kg/m2 (normal weight), 23–27.5 kg/m2 (overweight), and ≥ 27.5 kg/m2 (obese). Multiple logistic regression analyses were used to estimate odds ratio (OR) and 95% confidence interval (CI) after adjustment for covariates. Results: Overall, the prevalence of Asians was 23.3% for obesity and 40.0% for overweight. The obesity prevalence was higher in Asians who were males, aged 45–64 years old, had higher family income, were current smokers, never got married, had lower education level, had an insufficient level of physical activity, and had more frequent consumption of fast foods. After adjusting for other factors, compared to Whites, being Hispanics and Blacks were associated with higher odds of obesity (OR = 1.47, 95%CI = 1.31–1.65; OR = 2.04, 95%CI = 1.65–2.53, respectively); being Chinese, Korean, and Vietnamese were associated with lower odds of obesity (OR = 0.28, 95%CI = 0.18–0.45; OR = 0.14, 95%CI = 0.04–0.46; OR = 0.28, 95%CI = 0.14–0.58, respectively). Compared to Chinese, being Japanese and Filipino were associated with higher odds of obesity (OR = 2.75, 95%CI = 1.52–4.95; OR = 2.90, 95%CI = 1.87–4.49, respectively). Conclusions: The prevalence of adult obesity was high among Asian Americans in California. Ethnic/racial disparities in obesity among Asian Americans in California were observed in 2013–2014. Compared to Whites, being Chinese, Korean, Vietnamese were associated with lower odds of obesity. Among Asians, compared to Chinese, being Japanese and being Filipino were associated with higher odds of obesity. These findings can help design better interventions to reduce racial and ethnic disparities in obesity, especially for Asian Americans
Relationship between Thermal Conductivity and Compressive Strength of Insulation Concrete: A Review
Developing insulation concrete with high strength is essential for the construction of energy saving buildings. This is important to achieve carbon neutrality in the modern building industry. This paper reviews the existing studies in the literature on insulation concrete. This paper aims to reveal the correlation between the thermal conductivity and strength of concrete and identify the most effective method to make insulation concrete with lower thermal conductivity but higher strength. The review is carried out from two perspectives, including the effects of different foaming methods and various lightweight aggregates. As for the foaming methods, the chemical and mechanical foaming methods are discussed. As for the lightweight aggregates, cenospheres, porous aggregates, aerogels, and phase change materials are assessed. It is clearly observed that the thermal conductivity and compressive strength of concrete can be fitted by a linear function. As for the foaming methods, chemical foaming using hydrogen peroxide is the most effective to produce concrete with relatively lower thermal conductivity and higher compressive strength. For concrete with lightweight aggregates, cenospheres are the best option. Finally, recommendations are made to develop concrete with lower thermal conductivity and higher strength
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