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Cadmium (Cd) contamination in paddy fields and its subsequent transfer in soil–rice systems are of particular concern. Significant discrepancies exist in the transfer process of Cd pollution sources from soil to rice. Here, we proposed a novel hybrid framework to reveal the priority of controlling Cd pollution sources in soil–rice systems, based on a high-dimensional geographical database. We further defined transfer potential (TP) to describe the ability of Cd from soil to rice (TPr = Cdr/Cds) and activated status (TPa = Cda/Cds), respectively, to reveal the priority sources of Cd pollution at the regional scale. The mining source has both high levels of TPr and TPa, which should be a controlled priority. Followed by traffic sources with a higher value of TPr, showing the risk to rice rather than the soil. The activated and enriched capacities of soil Cd are unequal in different sources that we attribute to the disparities of Cd transport in soil–rice systems. Cd contamination shows a significant spatial heterogeneity due to the difference in its transport performance. Our findings provide support for designing site-specific and pollution-targeted control priorities for suitable Cd pollution mitigation strategies at the regional scale.

This paper studies a class of singular differential equations $$\begin{aligned} -\left( \frac{\mathrm {d}}{{\mathrm {d}}x}-\frac{k}{x^{l}}-v\right) \left( \frac{{\mathrm {d}}}{{\mathrm {d}}x}+\frac{k}{x^{l}}+v\right) y=\lambda y \text { on }J=(0,1) , \end{aligned}$$ where $$k\ge \frac{1}{2},1\le l

The spread of illegal drug use among adult caregivers of children raises many serious concerns. These concerns are intensified in situations in which drug-using adults are responsible for providing for the care, safety, and general well-being of the children under their care. The relative complexity of these situations is further compounded by the absence of rigorous scientific inquires into the mental health of children being raised in such situations. This survey utilized the Symptom Checklist-90 (SCL-90) to measure the mental health and life satisfaction of the children (aged 8 to 18 years) with at least one parent who is a drug abuser. The analysis results show that the psychological health of the children is poor and the mental health of the children affects their life satisfaction. Parents who are addicted to drugs may have an impact on the life satisfactions of their children regardless of the age of the child, and the impact on boys is more serious than on girls.

A monitoring program of particulate matter was conducted at eight sampling sites in four highly industrialized cities (Shenyang, Anshan, Fushun, and Jinzhou) of Liaoning Province in Northeast China to identify the major potential sources of ambient PM2.5. A total of 814 PM2.5 and PM2.5–10 samples were collected between 2004 and 2005. All PM samples were collected simultaneously in four cities and analyzed gravimetrically for mass concentrations. A sum of 16 elemental species concentrations in the PM samples were determined using inductively coupled plasma atomic emission spectroscopy. Annual means of PM2.5 concentrations ranged from 65.0 to 222.0 μg m−3 in all the eight sampling sites, and the spatial and seasonal variations were discussed. Enrichment factors were calculated, and Cr, Cu, Zn, As, Cd, and Pb will be pollution-derived elements. Site-to-site comparisons of PM2.5 species in each city were examined using coefficient of divergence, revealing that the two sites in each city are similar in elemental species. Principle component analysis was used for preliminary source analysis of PM2.5. Three or four factors in each city were isolated, and similar sources (crustal source, coal combustion, vehicle exhaust, iron making, or some other metallurgical activities) were identified at four cities.

This paper investigates 2m-th (m ≥ 2) order singular p-Laplacian boundary value problems, and obtains the necessary and sufficient conditions for existence of positive solutions for sublinear 2m-th order singular p-Laplacian BVPs on closed interval.