Experimental study on the triaxial mechanical behaviors of the Cemented Paste Backfill: Effect of curing time, drainage conditions and curing temperature.

The application of CPB (Cemented Paste Backfill) can realize the clean, efficient, and safe mining of underground metal mines. Clear understanding on the triaxial mechanical properties of CPB is important to the CPB design and the stability analysis of the backfilled CPB structure. The triaxial mechanical properties of CPB can be significantly affected by the different curing conditions. In this research, triaxial compression tests of the CPB samples were carried out using the GCTS (Geotechnical Consulting & Testing System), and the considered curing conditions include different curing time (1, 3, 7 and 28 days), drainage conditions (drained and undrained) and curing temperatures (20 °C, 35 °C and 45 °C). The measured mechanical parameters were compared and analyzed against the framework of the Mohr-Coulomb criterion. Then, the vertical stress distribution of the backfilled CPB structure was calculated and discussed using the measured mechanical parameters. The results show that with the increase of the lateral constraint ratio (σc/Sd0), the elastoplastic stage of the measured deviator stress versus axial strain curve of CPB sample is gradually obvious. The peak deviator stress (Sdp) and the ultimate axial strain (εu) show the linear and negative exponential increase with the σc/Sd0 respectively. The number of cracks on the fractured surface of the CPB samples gradually decreased with the increase of σc/Sd0. The failure types of CPB samples were changed from tensile failure (σc/Sd0 = 0%) to the mixed tensile-shear failure (σc/Sd0≈10%) and compression-shear failure (σc/Sd0≥20%). Moreover, with the increase of curing time and curing temperature or under the drained curing condition, the peak deviator stress and cohesion (cb) of CPB can be significantly increased, but the corresponding internal friction angle (ϕb) is decreased. The shear mechanical parameters of CPB can significantly affect the vertical stress distribution inside the CPB structure. Therefore, when estimating the vertical stress distribution inside the backfilled CPB structure in engineering practices, it is necessary to focus on the changes of CPB shear parameters (cb and ϕb) caused by different curing conditions.

Competitive adsorption of vanillin and syringaldehyde on a macro-mesopore polymeric resin: modeling.

Vanillin and syringaldehyde are widely used as flavoring and fragrance agents in the food products. The potential of a macro-mesoporous adsorption resin was assessed for separation of these binary mixtures. This work focuses on modeling of the competitive adsorption behaviors and exploration of the adsorption mechanism. The characterization results showed the resin had a large BET surface area and specific pore structure with hydrophobic properties. By analysis of the physicochemical properties of the solutes and the resin, the separation mechanism was mainly contributed by hydrophobic effect. Subsequently, the competitive Langmuir isotherm model was used to fit the competitive adsorption isotherms. The pore diffusion coefficient was obtained by macropore diffusion model. Afterwards, a mathematical model was established to predict the breakthrough curves of the binary mixture at various operating conditions. The data and model presented are valuable for design and simulation of the continuous chromatographic separation process.

Explaining religious differentials in family-size preference: Evidence from Nepal in 1996.

We examine how religio-ethnic identity, individual religiosity, and family members' religiosity were related to preferred family size in Nepal in 1996. Analyses of survey data from the Chitwan Valley Family Study show that socio-economic characteristics and individual experiences can suppress, as well as largely account for, religio-ethnic differences in fertility preference. These religio-ethnic differentials are associated with variance in particularized theologies or general value orientations (like son preference) across groups. In addition, individual and family religiosity are both positively associated with preferred family size, seemingly because of their association with religious beliefs­beliefs that are likely to shape fertility strategies. These findings suggest the need for improvements in how we conceptualize and measure supra-individual religious influence in a variety of settings and for a range of demographically interesting outcomes.

Prevalence of Diabetes and Prediabetes in Adults from a Third-Tier City in Eastern China: A Cross-Sectional Study.

INTRODUCTION: The aims of this study were to investigate the prevalence of adult diabetes and prediabetes in Bengbu (eastern China) in 2017, and to identify measures that can be taken to reduce the prevalence of diabetes and prediabetes in this region. METHODS: A stratified cluster random sampling method was used in the study. Two sampling sites were randomly selected from each of the four districts of Bengbu City, and all permanent residents (resident for ≥ 5 years) at all eight sampling sites aged 18 years or above were cluster sampled, which led to the sampling of 3388 adults. After screening, a total of 3144 respondents were enrolled in the study. The t test was utilized to compare the mean parameter values of the males and the females, and variance analysis was employed to compare the mean values of the nondiabetic, prediabetic, and diabetic groups. The chi-squared test was used to compare rates. Logistic regression was used for multivariate analysis, and the statistical significance level α was set to 0.05. RESULTS: The mean ages of the male and female groups were 51.1 ± 15.7 and 49.4 ± 15.1 years, respectively (p < 0.05). The diabetes prevalence in adults was 11.5% (8.4% after standardization), while the prevalence of prediabetes in adults was 32.0% (27.6% after standardization). The prevalence of diabetes and that of prediabetes gradually increased with age (both p < 0.05). Older age, hypertension, overweight status, obesity, central obesity, current smoker status, low serum high-density lipoprotein level, and high serum low-density lipoprotein level were all significantly associated with a higher risk of diabetes (p < 0.05). CONCLUSION: The prevalence of diabetes and that of prediabetes in adults in Bengbu City remain high. Intervention aimed at reducing the occurrence of diabetic complications and preventing prediabetes from further development is urgently required.

Bio-butanol sorption performance on novel porous-carbon adsorbents from corncob prepared via hydrothermal carbonization and post-pyrolysis method.

A series of porous-carbon adsorbents termed as HDPC (hydrochar-derived pyrolysis char) were prepared from corncob and used for the 1-butanol recovery from aqueous solution. The influences of pyrolysis temperature on properties of the adsorbents were systematically investigated. The results showed that hydrophobicity, surface area, and pore volume of HDPC samples increased with an increase in pyrolysis temperature. Furthermore, the adsorption mechanism of 1-butanol on the adsorbents was explored based on correlation of the samples properties with adsorption parameters extracted from the 1-butanol adsorption isotherms (K F and Q e12 ). Overall, the 1-butanol adsorption capacity increased with a decrease in polarity and an increase in aromaticity, surface area and pore volume of HDPC samples. However, at different pyrolysis temperature, the factors causing the increase of 1-butanol adsorption on the adsorbents are variable. The kinetic experiments revealed that the pores played a vital role in the 1-butonal adsorption process. The intraparticle diffusion model was used to predict the adsorption kinetic process. The simulation results showed that intraparticle diffusion was the main rate-controlling step in the 1-butanol adsorption process.

Challenges of introducing participant observation to community health research.

Participant observation elicits unique observation data from both an insider's and an outsider's perspectives. Despite the growing tendency to adopt participant observation strategies in health care research regarding health-related beliefs and types of behavior, the use of participant observation in current research is mostly limited to structured clinical settings rather than community settings. In this paper, we describe how we use participant observation in a community health research study with Chinese-born immigrant women. We document discrepancies between these women's beliefs and types of behavior regarding health and health promotion. We further discuss the ethnical, time, and setting challenges in community health research using participant observation. Possible solutions are also discussed.

Quality of life and health status among prostate cancer survivors and noncancer population controls.

OBJECTIVE: To examine whether quality of life (QOL), health status, and the relationships between them varied by having a prostate cancer history. This study helps to inform the interface between aging-related health decline and the survival state among older men with prostate cancer, which is an important yet understudied public health issue. METHODS: Hierarchical linear models were used to analyze the cross-sectional data from the nationally representative population-based Medical Expenditure Panel Survey. Using propensity score matching, survivors (respondents with prostate cancer history) and controls (respondents without a history of any cancer) (N = 193 pairs) were matched based on 7 sociodemographic and health-related factors. QOL was measured using the mental and physical component scores of the SF-12 (SF-36.org). Health status included comorbidities, activities of daily living (ADL), instrumental ADL, and depressed mood. RESULTS: In bivariate analyses, survivors reported worse physical (42.72 vs 45.45 respectively; P = .0040) and mental QOL (51.59 vs 53.73 respectively; P = .0295) and more comorbidities (3.25 vs 2.78 respectively; P = .0139) than controls. In multivariate analyses, for both survivors and controls, better physical QOL was associated with fewer comorbidities (P <.0001), no need help with ADL (P = .0011) and IADL (P = .0162), and less depressed mood (P <.0001); better mental QOL was associated with no need help with IADL (P = .0005) and less depressed mood (P <.0001). CONCLUSION: QOL of older men is affected by physical, functional, and psychological factors rather than prostate cancer history. Clinicians need to attend to aging-related health issues when providing care for prostate cancer survivors to improve QOL.