Heavy Metals in Soil and Crops of an Intensively Farmed Area: A Case Study in Yucheng City, Shandong Province, China

Yucheng City is located in northwestern Shandong Province, China, and is situated on the Huang-Huai-Hai Plain, the largest alluvial plain in China. In this study, 86 surface soil samples were collected in Yucheng City and analyzed for cation exchange capacity (CEC), soil organic matter (SOM), pH, available phosphorus (avail. P), phosphorus (P), aluminum (Al), and iron (Fe). These soils were also analyzed for ‘total’ chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), mercury (Hg), cadmium (Cd), and lead (Pb), together with 92 wheat samples and 37 corn samples. There was no obvious heavy metal contamination in the soil and irrigation water. But the long-term accumulation of heavy metals in soil has lead to an increase of Ni, As, Hg and Pb concentrations in some of wheat and corn samples and Cd in wheat samples. Because of the numerous sources of soil heavy metals and the lower level of heavy metal in irrigation water, there is no significant relation between soil heavy metal concentrations and irrigation water concentrations. Cr, Ni were mainly from the indigenous clay minerals according to multivariate analysis. Little contribution to soil heavy metal contents from agricultural fertilizer use was found and the local anomalies of As, Cd, Hg, Pb in wheat and corn grain are attributed to the interactive effects of irrigation and fertilizer used. Aerial Hg, however may also be the source of Hg for soil, wheat and corn

Hazardous Chemicals Road Transportation Accidents and the Corresponding Evacuation Events from 2012 to 2020 in China: A Review

Based on accident data from the China Chemical Accident Information Network, detailed information was obtained from 2657 hazardous chemicals road transportation accidents (HCRTAs) and 148 evacuations caused by these accidents that occurred in China from 2012 to 2020. The characteristics and the development trend of the present HCRTAs in China and the rate of emergency are obtained via statistical analysis. Based on the probability of evacuation scenarios via historical statistics, the social cost of labor loss value of participating emergency responders, and evacuees’ placement and transfer cost as the consequences of evacuation events, an evacuation event grading model based on social risk assessment is constructed. Evaluating and classifying the risk of evacuation events caused by HCRTAs (148), the results demonstrated that the social risk caused by emergency scenarios F_61 (leakage due to overturning of hazardous chemical vehicles, which led to evacuation) and F_91 (leakage due to rear-end of hazardous chemical vehicles, which led to evacuation) was higher than other emergency scenarios. To reduce the dangers caused by HCRTAs, the framework for improving the emergency response capacity of communities is discussed and analyzed based on five aspects, which comprise land use planning, city construction, education promotion, information construction, and the layout of emergency resources

Data from: Designing efficient hybrid strategies for information spreading in scale-free networks

Designing a spreading strategy is one of the critical issues strongly affecting spreading efficiency in complex networks. In this paper, to improve the efficiency of information spreading in scale-free networks, we propose four hybrid strategies by combing two basic strategies, i.e., (1) the LS (in which information is preferentially spread from the Large-degree vertices to the Small-degree ones) and (2) the SL (in which information is preferentially spread from the Small-degree vertices to the Large-degree ones). The objective in combining the two basic LS and SL strategies is to fully exploit the advantages of both strategies. To evaluate the spreading efficiency of the proposed four hybrid strategies, we first propose an information spreading model. Then, we introduce the details of the proposed hybrid strategies that are formulated by combining LS and SL. Third, we build a set of scale-free network structures by differently configuring the relevant parameters. In addition, finally, we conduct various Monte Carlo experiments to examine the spreading efficiency of the proposed hybrid strategies in different scale-free network structures. Experimental results indicate that the proposed hybrid strategies are effective and efficient for spreading information in scale-free networks

Experimental Results

The Monte Carlo experimental results of spreading time in different complex networks

Experimental Investigation on the Cooling and Inerting Effects of Liquid Nitrogen Injected into a Confined Space

As a highly effective and environmentally benign suppression agent, liquid nitrogen (LN2) has been widely used for fire extinguishing in plants, dwellings, enclosed underground tunnels, and other confined spaces through cooling and inerting. It is of great significance to understand the cooling and inerting effects of LN2 injected into a confined space. A confined-space experimental platform was developed to study the injecting LN2 into the platform with different injection parameters, such as mass flux, pipe diameter, and inclination angle. In addition, a mathematical model of quantitatively assessing cooling and inerting effects was proposed by using heat transfer capacity, inerting coefficient, and cooling rate. Results showed that the inerting effect was gradually enhanced with a mass flux increasing from 0.014 to 0.026 kg/s and then tended to level off; an appropriate pipe diameter of 12 mm was optimal for the cooling and inerting effects in this experiment. In addition, a positively increasing inclination angle could contribute to the cooling and inerting effects. However, there was little effect on the cooling and inerting with an inclination angle less than 0°. This study can provide technical guidances for environmentally friendly fire extinguishing with LN2 in a confined space

Efficient method for identifying influential vertices in dynamic networks using the strategy of local detection and updating

The identification of influential vertices in complex networks can facilitate understanding and prediction of the behaviour of real systems. In this paper, we propose an efficient method for identifying influential vertices in dynamic networks by exploiting the strategy of local detection and updating. The essential strategy of the proposed local detection and updating method is to locally detect the altered vertices in dynamic networks and locally update the influence metrics of the altered vertices, without the need to globally calculate the influence of all vertices. To evaluate the computational efficiency of the proposed local detection and updating method, we design 15 groups of experimental tests for three types of complex networks (the Barabási–Albert (BA) scale-free network, the Watts–Strogatz (WS) small-world network, and the Erdö s–Rényi (ER) random network). Experimental results demonstrate that: (1) the sequential version of the proposed method is approximately 3 times faster than the global calculation method for the small-world networks and random networks; (2) the parallel version of the proposed method, which was developed on a multi-core CPU, is approximately 10 times faster than the global calculation method for the scale-free networks. The proposed local detection and updating method can be employed to efficiently identify the influential vertices and predict the changes in influence of specified sets of vertices in dynamic networks

Features of the Asynchronous Correlation between the China Coal Price Index and Coal Mining Accidental Deaths.

The features of the asynchronous correlation between accident indices and the factors that influence accidents can provide an effective reference for warnings of coal mining accidents. However, what are the features of this correlation? To answer this question, data from the China coal price index and the number of deaths from coal mining accidents were selected as the sample data. The fluctuation modes of the asynchronous correlation between the two data sets were defined according to the asynchronous correlation coefficients, symbolization, and sliding windows. We then built several directed and weighted network models, within which the fluctuation modes and the transformations between modes were represented by nodes and edges. Then, the features of the asynchronous correlation between these two variables could be studied from a perspective of network topology. We found that the correlation between the price index and the accidental deaths was asynchronous and fluctuating. Certain aspects, such as the key fluctuation modes, the subgroups characteristics, the transmission medium, the periodicity and transmission path length in the network, were analyzed by using complex network theory, analytical methods and spectral analysis method. These results provide a scientific reference for generating warnings for coal mining accidents based on economic indices

Depression-related brain connectivity analyzed by EEG event-related phase synchrony measure

This study is to examine changes of functional connectivity in patients with depressive disorder using synchronous brain activity. Event-related potentials were acquired during a visual oddball task in 14 patients with depressive disorder and 19 healthy controls. Electroencephalogram recordings were analyzed using event-related phase coherence to obtain the functional network. Alteration of the phase synchronization index (PSI) of the functional network was investigated. Patients with depression showed a decreased number of significant electrode pairs in delta phase synchronization, and an increased number of significant electrode pairs in theta, alpha, and beta phase synchronization, compared with controls. Patients with depression showed lower target-dependent PSI increment in the frontal-parietal/temporal/occipital electrode pairs in delta-phase synchronization than healthy participants. However, patients with depression showed higher target-dependent PSI increments in theta band in the prefrontal/frontal and frontal-temporal electrode pairs, higher PSI increments in alpha band in the prefrontal pairs, and higher increments of beta PSI in the central and right frontal-parietal pairs than controls. It implied that the decrease in delta PSI activity in major depression may indicate impairment of the connection between the frontal and parietal/temporal/occipital regions. The increase in theta, alpha, and beta PSI in the frontal/prefrontal sites may reflect the compensatory mechanism to maintain normal cognitive performance. These findings may provide a foundation for a new approach to assess the effectiveness of therapeutic strategies for depression

Aging, health and place in residential care facilities in Beijing, China

In recent years, residential care has become an alternative option for elder care in Beijing, China. Little is known, however, about the well-being of elderly residents and the relationship between their health and living in residential care facilities (RCFs). Hence this research aims to understand the well-being of elderly residents in RCFs and how the environment of RCFs affects elderly people's everyday activities and health. The concepts of therapeutic landscapes, active aging, and well-being contribute to understanding the relationships among aging, health, and environment within RCF settings. Qualitative data from 46 in-depth semi-structured interviews with RCF managers, elderly residents, and family members in Beijing were transcribed and analysed using the constant comparative method. The results show that most of the elderly residents are satisfied with their lives in RCFs, but a few of them feel isolated and depressed after their relocation. Each RCF, as a place with its unique physical and social environment, has a significant influence on the elderly residents' physical and psychological well-being. Individual factors such as characteristics of elderly residents, their attitudes on aging and residential care, and family support also play important roles in their adaptation and well-being after relocation from home to RCFs. Although this study focuses on residential care at the local level, it sheds light on future research on geographical and socio-cultural meanings of elder care at local, regional, and national levels in China.Therapeutic landscapes China Aging Residential care Well-being