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Microenvironmental time-activity patterns in Chongqing, China

Yu ZHAO, Shuxiao WANG, Gangcai CHEN, Fei WANG, Kristin AUNAN, Jiming HAO

《环境科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 200-209 doi: 10.1007/s11783-009-0010-y

摘要： An investigation using recall questionnaires was conducted in winter and autumn 2006 to evaluate the time-activity patterns in Chongqing, China. The average time spent in seven microenvironments (MEs) including outdoors, transit, living room, bedroom, kitchen, classroom/office, and other indoors were found to be about 3.5, 1.1, 2.5, 9.7, 1.4, 4.2, and 1.7 h per day, respectively. According to the results of a nonparametric test, the sampling period and day of week were significant for the variation of the time spent in all MEs except for transit and outdoors. The time budget was analyzed using a general linear model (GLM), which exhibited significant variability by demographic factors such as gender, age, residence, education, and household income.

关键词： time-activity patterns     microenvironment     general linear model (GLM)     Chongqing     China    

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Associations of sleeping patterns and isotemporal substitution of other behavior with the prevalence

《医学前沿（英文）》 doi: 10.1007/s11684-023-1019-5

摘要： Studies have found a U-shaped relationship between sleep duration and chronic kidney disease (CKD) risk, but limited research evaluated the association of reallocating excessive sleep to other behavior with CKD. We included 104 538 participants from the nationwide cohort of the Risk Evaluation of Cancers in Chinese Diabetic Individuals: A Longitudinal Study, with self-reported time of daily-life behavior. Using isotemporal substitution models, we found that substituting 1 h of sleeping with sitting, walking, or moderate-to-vigorous physical activity was associated with a lower CKD prevalence. Leisure-time physical activity displacement was associated with a greater prevalence reduction than occupational physical activity in working population. In stratified analysis, a lower CKD prevalence related to substitution toward physical activity was found in long sleepers. More pronounced correlations were observed in long sleepers with diabetes than in those with prediabetes, and they benefited from other behavior substitutions toward a more active way. The U-shaped association between sleep duration and CKD prevalence implied the potential effects of insufficient and excessive sleep on the kidneys, in which the pernicious link with oversleep could be reversed by time reallocation to physical activity. The divergence in the predicted effect on CKD following time reallocation to behavior of different domains and intensities and in subpopulations with diverse metabolic statuses underlined the importance of optimizing sleeping patterns and adjusting integral behavioral composition.

关键词： sleep     physical activity     chronic kidney disease     isotemporal substitution     behavioral pattern    

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Joint association of physical activity/screen time and diet on CVD risk factors in 10-year-old children

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 428-435 doi: 10.1007/s11684-012-0232-4

摘要：

The increasing prevalence of childhood overweight and obesity has been associated with an increased risk for cardiovascular disease (CVD). While several studies examined the effect of single behaviors such as physical activity (PA), sedentary behavior or diet on CVD risk, there is a lack of research on combined associations, specifically in children. Therefore, the purpose of this study was to examine the joint association of PA or screen time (ST) and diet on CVD risk factors in children. PA, ST and diet were assessed via questionnaire in 210 fifth grade students (age: 10.6±0.4 years). The healthy eating index (HEI) was subsequently calculated as indicator for diet quality. Height, weight, % body fat, and resting blood pressure were measured according to standard procedures and blood samples obtained via fingerprick were assayed for blood lipids. Total cholesterol HDL ratio (TC:HDL), mean arterial pressure (MAP), and % body fat were used as indicators of CVD risk. 55% of children did not meet current PA recommendations on at least 5 days/week and 70% exceeded current recommendations for ST. Further, only 2.5% possessed a “good” diet (HEI>80). There was no significant association of PA or ST and diet on CVD risk score. Neither TC:HDL, MAP, and % body fat nor the total CVD risk score was significantly correlated with diet, PA, or ST. Children in the high PA group, however, had significantly better diet scores. Despite the fact that self-reported PA, ST, or dietary intake were not directly related to CVD risk in this sample, higher activity levels were associated with a healthier diet and lower ST indicating an overall healthier lifestyle of this subgroup.

关键词： exercise     sedentary behavior     metabolic syndrome     health behavior     adolescents     TV time     healthy eating index    

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Effects of hydraulic retention time on nitrification activities and population dynamics of a conventional

Hongyan LI, Yu ZHANG, Min YANG, Yoichi KAMAGATA

《环境科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 43-48 doi: 10.1007/s11783-012-0397-8

摘要： The effects of hydraulic retention time (HRT) on the nitrification activities and population dynamics of a conventional activated sludge system fed with synthetic inorganic wastewater were investigated over a period of 260 days. When the HRT was gradually decreased from 30 to 5 h, the specific ammonium-oxidizing rates (SAOR) varied between 0.32 and 0.45 kg (kg mixed liquor suspended solids (MLSS)·d) , and the specific nitrate-forming rates (SNFR) increased from 0.11 to 0.50 kg (kg MLSS·d) , showing that the decrease in HRT led to a significant increase in the nitrite oxidation activity. According to fluorescence in situ hybridization (FISH) analysis results, the proportion of ammonia-oxidizing bacteria (AOBs) among the total bacteria decreased from 33% to 15% with the decrease in HRT, whereas the fraction of nitrite-oxidizing bacteria (NOBs), particularly the fast-growing sp., increased significantly (from 4% to 15% for NOBs and from 1.5% to 10.6% for sp.) with the decrease in HRT, which was in accordance with the changes in SNFR. A short HRT favored the relative growth of NOBs, particularly the fast-growing sp., in the conventional activated sludge system.

关键词： ammonia-oxidizing bacteria     hydraulic retention time     nitrification activity     nitrite-oxidizing bacteria     population dynamics    

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Effects of riparian vegetation patterns on the distribution and potential loss of soil nutrients: a case

Erhui GUO,Liding CHEN,Ranhao SUN,Zhaoming WANG

《环境科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 279-287 doi: 10.1007/s11783-014-0667-8

摘要： A riparian ecosystem is an ecological transition zone between a river channel and terrestrial ecosystems. Riparian ecosystems play a vital role in maintaining stream health and bank stabilization. The types of riparian vegetation have changed greatly because of human activities along the Wenyu River. This study examines the impact of riparian vegetation patterns on water pollution due to soil nutrient loss. Four riparian vegetation patterns from the river channel to the upland were chosen as the focus of this study: grassland, cropland, grassland-cropland, and grassland-manmade lawn. The different distributions of soil nutrients along vegetation patterns and the potential risk of nutrient loss were observed and compared. The results showed that riparian cropland has the lowest value of total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), available phosphorus (AP), and organic matter (OM), but it has the highest soil bulk density (BD). The distributions of soil TN, TP, AN, AP, and OM exhibited a declining trend from the upland toward the river channel for riparian cropland, whereas a different trend was observed for the riparian grassland. The vegetation patterns of grassland-cropland and grassland-manmade lawn show that the grassland in the lower slope has more nutrients and OM but lower soil BD than the cropland or manmade lawn in the upper slope. So, the lower-slope grassland may intercept and infiltrate surface runoff from the upland. The lower-slope grassland has higher levels of soil TN, TP, AN, and AP, and thus it may become a new source of nutrient loss. Our results suggest that the management of the riparian vegetation should be improved, particularly in densely populated areas, to control soil erosion and river pollution.

关键词： riparian     vegetation patterns     soil nutrient distribution     nutrient loss     management    

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Exploring the development of municipal solid waste disposal facilities in Chinese cities: patterns and

《环境科学与工程前沿（英文）》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1739-4

摘要：

● We tracked Chinese cities’ MSW disposal infrastructure development history.

关键词： China     Municipal solid waste (MSW)     Landfill     Incineration     Proliferation patterns     Driving forces    

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Analysis of driving forces behind diversified carbon dioxide emission patterns in regions of the mainland

Xin TIAN, Hidefumi IMURA, Miao CHANG, Feng SHI, Hiroki TANIKAWA

《环境科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 445-458 doi: 10.1007/s11783-011-0330-6

摘要： China has large regional disparities in carbon dioxide CO emissions with economic development among its 31 provincial mainland regions. This paper investigates these disparities in CO emission patterns and identifies the factors underlying the differences. Results show that the 30 study China's mainland provinces (Tibet not included) can be divided into seven groups with three typical CO emission patterns. Index decomposition results indicate that changes in economic development, the industrial sector, and technology contribute far more to increased CO emissions than do population, energy structure, and other sectors. Close inspection reveals that different industry structures and technology contribute greatly to the differences observed in CO emissions between provinces with similar economic output. This study highlights the importance of region-specific industrial structure adjustment policies, especially for regions transitioning to heavy industry and for those still in the primary stages of industrialization. The potential application of a domestic carbon emissions trading system, to encourage regional investment in updated technology, is also discussed.

关键词： carbon dioxide emission patterns     China     economic development     index decomposition analysis     industrialization    

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Early-life famine exposure, adulthood obesity patterns, and risk of low-energy fracture

《医学前沿（英文）》 doi: 10.1007/s11684-023-1023-9

摘要： Malnutrition in early life increases the risk of osteoporosis, but the association of early-life undernutrition combined with adulthood obesity patterns with low-energy fracture remains unknown. This study included 5323 community-dwelling subjects aged ≥40 years from China. Early-life famine exposure was identified based on the participants’ birth dates. General obesity was assessed using the body mass index (BMI), and abdominal obesity was evaluated with the waist-to-hip ratio (WHR). Low-energy fracture was defined as fracture occurring after the age of 40 typically caused by falls from standing height or lower. Compared to the nonexposed group, the group with fetal, childhood, and adolescence famine exposure was associated with an increased risk of fracture in women with odds ratios (ORs) and 95% confidence intervals (CIs) of 3.55 (1.57–8.05), 3.90 (1.57–9.71), and 3.53 (1.05–11.88), respectively, but not in men. Significant interactions were observed between fetal famine exposure and general obesity with fracture among women (P for interaction = 0.0008). Furthermore, compared with the groups with normal BMI and WHR, the group of women who underwent fetal famine exposure and had both general and abdominal obesity had the highest risk of fracture (OR, 95% CI: 3.32, 1.17–9.40). These results indicate that early-life famine exposure interacts with adulthood general obesity and significantly increases the risk of low-energy fracture later in life in women.

关键词： famine     obesity     body mass index     waist-to-hip ratio     low-energy fracture    

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Social media and mobility landscape: Uncovering spatial patterns of urban human mobility with multi source

Yilan Cui, Xing Xie, Yi Liu

《环境科学与工程前沿（英文）》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1068-1

摘要：

Check-in and survey data are explored to identify personal activity-specific places.

Ways for detecting and moderating sample bias of Weibo check-in data is proposed.

A graphic representation of urban activity intensity in Beijing, China is presented.

The potential application of Weibo check-in data for urban analysis is introduced.

关键词： Social media     Human mobility     Population bias     Sample reconstruction     Data integration    

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Clinical efficacy of comprehensive therapy based on traditional Chinese medicine patterns on patients

《医学前沿（英文）》 2022年 第16卷 第5期   页码 736-744 doi: 10.1007/s11684-021-0870-5

摘要： Effective therapy options for pneumoconiosis are lacking. Traditional Chinese medicine (TCM) presents a favorable prospect in the treatment of pneumoconiosis. A pilot study on TCM syndrome differentiation can evaluate the clinical efficacy and safety of TCM and lay a foundation for further clinical research. A double-blind, randomized, and placebo-controlled trial was conducted for 24 weeks, in which 96 patients with pneumoconiosis were randomly divided into the control and treatment groups. Symptomatic treatment was conducted for the two groups. The treatment group was treated with TCM syndrome differentiation, and the control group was treated with placebo. The primary outcomes were the six-minute walking distance (6MWD) and the St. George Respiratory Questionnaire (SGRQ) score. The secondary outcomes were the modified British Medical Research Council Dyspnea Scale (mMRC), Chronic Obstructive Pulmonary Disease Assessment Test (CAT), Hospital Anxiety and Depression Scale (HADS), and pulmonary function. Only 83 patients from the 96 patients with pneumoconiosis finished the study. For the primary outcome, compared with the control groups, the treatment group showed a significantly increased 6MWD (407.90 m vs. 499.51 m; 95% confidence interval (CI) 47.25 to 135.97; P <0.001) and improved SGRQ total score (44.48 vs. 25.67; 95% CI −27.87 to −9.74; P <0.001). The treatment group also significantly improved compared with the control group on mMRC score (1.4 vs. 0.74; 95% CI −1.08 to −0.23; P =0.003), CAT score (18.40 vs. 14.65; 95% CI −7.07 to −0.43; P =0.027), and the total symptom score (7.90 vs. 5.14; 95% CI −4.40 to −1.12; P <0.001). No serious adverse events occurred. This study showed that TCM syndrome differentiation and treatment had a favorable impact on the exercise endurance and quality of life of patients with pneumoconiosis.

关键词： pneumoconiosis     randomized controlled trials     traditional Chinese medicine    

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以喂养方式视角浅析新时期城市基层计生优质服务

严小青

《中国工程科学》 2014年 第16卷 第5期   页码 24-30

摘要：

通过选取杭州市上城区社区卫生院109 例婴儿及其母亲为调查对象，利用SPSS18.0 软件分别从一般参考量、影响喂养方式相关性因素以及基层计生优质服务需求进行数据统计分析，从而得到影响母乳喂养因素、喂养方式与婴儿体格关系以及服务需求重点，从而提出要从卫生计生联手、育医结合，立足基层架构群众满意服务网络；探索途径、优化服务，实现流动人口优质服务一盘棋；强化队伍、创新机制，探索建立科学规范服务考核评估体系三方面全面提升新时期基层计生优质服务水平。

关键词： 喂养方式     统计分析     计生优质服务    

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contributions of friction and plastic deformation to machined surface temperatures and residual stress patterns

Subhash ANURAG, Yuebin GUO,

《机械工程前沿（英文）》 2010年 第5卷 第3期   页码 247-255 doi: 10.1007/s11465-010-0097-7

摘要： Temperature on the machined surface is critical for surface integrity and the performance of a precision component. However, the temperature of a machined surface is challenging for in-situ measurement. Furthermore, the individual contribution of tool/work friction and plastic deformation of work materials to surface temperature is very difficult to quantify because the measured temperature is always the resultant temperature. This lack of understanding on the temperature distribution blocks the design of effective cutting tool geometries and materials to minimize surface temperature. This study provides a finite element method based on a predictive model to decouple the contributions of tool/work friction and material plastic deformation to surface temperature in a dry cutting process. The study shows that the plastic deformation of work material contributes to the majority of surface temperature, whereas the tool/work friction contribution is secondary. High temperatures are produced when more materials are plowed under the cutting edge. A large tool/work friction leads to higher surface temperatures, and the use of a cutting tool with physical properties in process simulation significantly improves the accuracy of predicted surface temperatures. Residual stress reversal from subsurface maximum residual to surface maximum residual stress may occur when tool/work friction increases.

关键词： surface temperature     friction     residual stress     finite element analysis (FEA)     dry cutting     tool property    

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IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 126-131 doi: 10.1007/s11684-012-0236-0

摘要：

Recent evidence demonstrates the independent negative effects of sedentary behavior on health, but there are few objective measures of sedentary behavior. Most instruments measure physical activity and are not validated as measures of sedentary behavior. The purpose of this study was to evaluate the validity of the IDEEA system’s measures of sedentary and low-intensity physical activities: lying, reclining, sitting and standing. Thirty subjects, 14 men and 16 women, aged 23 to 77 years, body mass index (BMI) between 18 to 34 kg/m2, participated in the study. IDEEA measures were compared to direct observation for 27 activities: 10 lying in bed, 3 lying on a sofa, 1 reclining in a lawn chair, 10 sitting and 3 standing. Two measures are reported, the percentage of activities accurately identified and the percentage of monitored time that was accurately labeled by the IDEEA system for all subjects. A total of 91.6% of all observed activities were accurately identified and 92.4% of the total monitored time was accurately labeled. The IDEEA system did not accurately differentiate between lying and reclining so the two activities were combined for calculating accuracy. Using this approach the IDEEA system accurately identified 96% of sitting activities for a total of 97% of the monitored sitting time, 99% and 99% for standing, 87% and 88% for lying in bed, 87% and 88% for lying on the sofa, and 83% and 83% for reclining on a lawn chair. We conclude that the IDEEA system accurately recognizes sitting and standing positions, but it is less accurate in identifying lying and reclining positions. We recommend combining the lying and reclining activities to improve accuracy. The IDEEA system enables researchers to monitor lying, reclining, sitting and standing with a reasonable level of accuracy and has the potential to advance the science of sedentary behaviors and low-intensity physical activities.

关键词： IDEEA     activity monitor     sedentary behavior    

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Electromagnetic induction mapping at varied soil moisture reveals field-scale soil textural patterns

Hiruy ABDU, David A. ROBINSON, Janis BOETTINGER, Scott B. JONES

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 135-145 doi: 10.15302/J-FASE-2017143

摘要： Knowledge of the spatial distribution of soil textural properties is important for determining soil moisture storage and soil hydraulic transport properties. Capturing field heterogeneity without exhaustive sampling and costly sample analysis is difficult. Our objective was to employ electromagnetic induction (EMI) mapping in low apparent electrical conductivity (EC ) soils at varying soil water contents to capture time invariant properties such as soil texture. Georeferenced EC measurements were taken using a ground conductivity meter on six different days where volumetric water content ( ) varied from 0.11 to 0.23. The 50 m × 50 m field included a subsurface gravelly patch in an otherwise homogeneous silt-loam alluvial soil. Ordinary block kriging predicted EC at unsampled areas to produce 1-m resolution maps. Temporal stability analysis was used to divide the field into three distinct EC regions. Subsequent ground-truthing confirmed the lowest conductivity region correlated with coarse textured soil parent materials associated with a former high-energy alluvial depositional area. Combining maps using temporal stability analysis gives the clearest image of the textural difference. These maps could be informative for modeling, experimental design, sensor placement and targeted zone management strategies in soil science, ecology, hydrology, and agricultural applications.

关键词： soil electrical conductivity     soil texture mapping     temporal stability analysis    

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Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancer

Jacqueline CONCHA, Caroline WEINSTEIN, María Elvira Zú?IGA

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 482-489 doi: 10.1007/s11705-013-1342-5

摘要： In the last years, sugar beet pectins have been the subject of several investigations involving extraction methodologies, chemical composition and functional properties. The structure of pectins, which depends on the extraction method, is decisive in their capacity to induce apoptosis on several cancer cell lines like colon, prostate and breast. In this work, sugar beet pectin extraction was performed in the following steps: lipid extraction with hexane, removal of soluble complex carbohydrates and proteins, and enzymatic treatment with amyloglucosidase, protease, and pectinase. The enzymatic treatment was carried out with Rohapect DA6L under the following conditions: 50°C, pH 4.0, 2% enzyme/substrate (E/S) ratio, 15 h, and a solid to liquid ratio of 1 ∶ 10. The pectic extract showed a degree of polymerization (DP) profile of 55.8% with DP≥7; 4.9% with DP6; 5.8% between DP2 and DP6 ; 4.7% with DP2; and 28.8% with DP1. The pectic extract was examined for its antiproliferative activity on the MCF-7 breast cancer cell line. At a concentration range of 12.5–25 mg/mL the pectic extract killed 80.6% of the cells, exhibiting a higher antiproliferative activity than 4-hydroxytamoxifen (4-OHT), a classical anticancer drug, which killed 56.5% of the cells.

关键词： pectic extracts     antiproliferative activity     breast cancer     enzymatic treatment    

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标题 作者 时间 类型 操作

Microenvironmental time-activity patterns in Chongqing, China

Yu ZHAO, Shuxiao WANG, Gangcai CHEN, Fei WANG, Kristin AUNAN, Jiming HAO

期刊论文

Associations of sleeping patterns and isotemporal substitution of other behavior with the prevalence

期刊论文

Joint association of physical activity/screen time and diet on CVD risk factors in 10-year-old children

null

期刊论文

Effects of hydraulic retention time on nitrification activities and population dynamics of a conventional

Hongyan LI, Yu ZHANG, Min YANG, Yoichi KAMAGATA

期刊论文

Effects of riparian vegetation patterns on the distribution and potential loss of soil nutrients: a case

Erhui GUO,Liding CHEN,Ranhao SUN,Zhaoming WANG

期刊论文

Exploring the development of municipal solid waste disposal facilities in Chinese cities: patterns and

期刊论文

Analysis of driving forces behind diversified carbon dioxide emission patterns in regions of the mainland

Xin TIAN, Hidefumi IMURA, Miao CHANG, Feng SHI, Hiroki TANIKAWA

期刊论文

Early-life famine exposure, adulthood obesity patterns, and risk of low-energy fracture

期刊论文

Social media and mobility landscape: Uncovering spatial patterns of urban human mobility with multi source

Yilan Cui, Xing Xie, Yi Liu

期刊论文

Clinical efficacy of comprehensive therapy based on traditional Chinese medicine patterns on patients

期刊论文

以喂养方式视角浅析新时期城市基层计生优质服务

严小青

期刊论文

contributions of friction and plastic deformation to machined surface temperatures and residual stress patterns

Subhash ANURAG, Yuebin GUO,

期刊论文

IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing

null

期刊论文

Electromagnetic induction mapping at varied soil moisture reveals field-scale soil textural patterns

Hiruy ABDU, David A. ROBINSON, Janis BOETTINGER, Scott B. JONES

期刊论文

Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancer

Jacqueline CONCHA, Caroline WEINSTEIN, María Elvira Zú?IGA

期刊论文