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In emerging economies, a significant amount of secondary resources are recycled by the informal sector, which can seriously harm the environment. However, some previous studies of industry management policy design ignored geographical factors. This paper introduces Geographic Information Systems into an agent-based cross-regional recycling model, and employs lead-acid batteries as an example. The model quantitatively displays the evolution of recycling markets in 31 provinces in Mainland China. Results show that: (1) High subsidies can significantly increase the number of formal enterprises in the short term, but their effectiveness decreases when the proportion of government funds in subsidies is above 80% in the long run; (2) The number of illegal recycling enterprises increases by 294% in eight inland provinces (e.g., Ningxia, Xinjiang) when all funds are invested in supervision, but this number is quite small in subsidy policy scenarios; (3) In four eastern regions, including Beijing and Tianjin, the number of illegal recycling enterprises decreases by 84% if supervision is more favored than subsidy; (4) In the optimal case where spatiotemporal factors are considered in all 31 regions, illegal recycling enterprises and waste lead emissions can be reduced by 95.59% and 45.85% nationwide. Our proposed recycling model offers a detailed simulation of multiple regions and diverse stakeholders, and serves as a useful reference for targeted recovery policies. Governments in inland regions like Ningxia and Xinjiang should implement subsidy policies, while supervision policies should be implemented in developed regions like Beijing and Tianjin., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Carbon trading is an effective way to limit global carbon dioxide emissions. The carbon pricing mechanisms play an essential role in the decision of the market participants and policymakers. This study proposes a carbon price prediction model, multi-decomposition-XGBOOST, which is based on sample entropy and a new multiple decomposition algorithm. The main steps of the proposed model are as follows: (1) decompose the price series into multiple intrinsic mode functions (IMFs) by using complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN); (2) decompose the IMF with the highest sample entropy by variational mode decomposition (VMD); (3) select and recombine some IMFs based on their sample entropy, and then perform another round of decomposition via CEEMDAN; (4) predict IMFs by XGBoost model and sum up the prediction results. The model has exhibited reliable predictive performance in both the highly fluctuating Beijing carbon market and the comparatively stable Hubei carbon market. The proposed model in Beijing carbon market achieves improvements of 30.437%, 44.543%, and 42.895% in RMSE, MAE, and MAPE, when compared to the single XGBoost models. Similarly, in Hubei carbon market, the RMSE, MAE, and MAPE based on multi-decomposition-XGBOOST model decreased by 28.504%, 39.356%, and 39.394%. The findings indicate that the proposed model has better predictive performance for both volatile and stable carbon prices., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Few reports of Cryptosporidium spp. in snakes in China have been published. To determine the infection rate and document the presence of Cryptosporidium in pet snakes using molecular methods, 273 fecal samples were collected from eight species of pet snakes from 13 pet households in Beijing, China, and were examined by PCR amplification of the small subunit ribosomal RNA gene. Cryptosporidium was detected from 17 of 273 (6.2%) samples, and nine out of 13 households tested positive for Cryptosporidium with a range of 3.3 to 33.3% among households showing significant difference (p < 0.01). The infection rate of Cryptosporidium for females and males was 6.5% (13/201) and 5.6% (4/72), respectively, showing no significant difference (p > 0.05). Six out of eight pet snake species tested positive for Cryptosporidium with a range of 4.2 to 9.1% among species, showing no significant difference (p > 0.05). Two Cryptosporidium species were identified: Cryptosporidium serpentis in 10 samples and Cryptosporidium varanii in seven samples. No zoonotic Cryptosporidium species occur in our study populations.

Objectives: The aim of this cross-sectional study was to investigate the association of serum 25-hydroxyvitamin D (25[OH]D) levels and vitamin D receptor (VDR) genotypes with skeletal muscle mass and function in elderly subjects in northern China., Methods: A total of 275 men and 510 women, ages 63.1 to 72.5 y, in two randomly selected communities in Beijing were investigated. The investigation included a questionnaire, physical measurements, muscle mass and function measurements, serum 25(OH)D levels, and VDR gene polymorphisms analysis., Results: In the group with 25(OH)D levels <10.0 ng/mL, the proportion with low handgrip strength was 3.04 times higher than that in the group with 25(OH)D levels >20.0 ng/mL for men (odds ratio: 3.04; 95% confidence interval, 1.13-8.20) but not for women. The general linear model showed that higher 25(OH)D levels and having T allele of Fok1 and the bb genotype of Bsm1 were significantly associated with more handgrip strength. The regression coefficients (β) were 1.80 (P < 0.01), 1.26 (P < 0.01), and 2.90 (P < 0.01), respectively. There was a significant interaction between 25(OH)D and VDR gene polymorphisms for handgrip strength for both Fok1 (β = 2.86; P < 0.01) and Bsm1 (β = 3.14; P = 0.02) after adjustment for potential confounders (sex, age, body mass index, fat mass, physical activity, sun exposure, energy, and protein intake)., Conclusions: 25(OH)D levels are associated with handgrip strength for men and this relationship could be modified with the interaction between 25(OH)D and VDR gene polymorphisms (Fok1 and Bsm1)., (Copyright © 2018. Published by Elsevier Inc.)