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Urban parks play a crucial role in urban public green infrastructure, providing recreational places for urban residents while carrying values of aesthetics, ecology, humanities, economy, life, and society. However, achieving an equitable and efficient spatial layout of urban parks is a challenging task due to limited urban space resources, which requires further exploration. This study employed multisource big data and GIS technology to constructed an indicator system for evaluating the equity-efficiency of urban park spatial distribution. We examined the spatial distribution of 85 parks across 62 sub-districts in the main urban area of Chengdu, the largest city in western China and the first Park City of China. The results demonstrated that equity was polarized, with an indicator value ranging from 0 to 0.77 and an average value of 0.32. The sub-district of Sansheng had the highest equity, while Wenjia and Kanghe had the lowest equity. Twenty-one sub-districts had no parks, and the equity of park spatial distribution in these areas was low. The efficiency indicator ranged from 0.20 to 0.62, with an average value of 0.40. The efficiency of the main urban area was high in the southwest and low in the northeast. The sub-district of Huangtianba had the highest efficiency, while Jinguanyi had the lowest efficiency. In the two-dimensional quadrant of equity-efficiency, 24 sub-districts had high equity and high efficiency, 13 sub-districts had high equity and low efficiency, 4 sub-districts had low equity and high efficiency, and 21 sub-districts had low equity and low efficiency. At the district level, only Chenghua District's park was spatial equitable and efficient, surpassing the average level of the main urban area. Finally, we discussed the findings in the context of planning policies for Chengdu in recent years. We proposed that strengthening the construction of small urban parks and green spaces, improving park facilities to meet the diverse social needs of people, and enhancing the quality and attractiveness of the parks are crucial for the future development of park green spaces in the main urban areas of Chengdu. [ABSTRACT FROM AUTHOR]

Comprehensive treatment of multifarious contaminations in waterbody demands multifunctional adsorbents with easy reusability, high efficiency, and broad-spectrum adsorption performance. Herein hydrothermally reduced graphene oxide/poly (vinyl alcohol) (TRGO/PVA) aerogels fulfilling these requirements were developed via a facile and green in situ hydrothermal reduction followed by direct sol-aerogel transformation strategy. The interfacial interaction between TRGO sheets and PVA macromolecules as proved by various methods could effectively prevent TRGO from aggregation, which improves mechanical and adsorption performances and assures reusability of aerogels. The aerogels demonstrate an attractive broad-spectrum universality in adsorbing diverse cationic, anionic and nonionic dyes, surpassing most adsorbents that could only remove either positively or negatively charged dyes. The aerogels demonstrate a promising synergetic effect for adsorption two oppositely charged dyes, exhibiting the highest total adsorption amount (>900 mg/g) among known absorbents for removing mixed dyes. Besides, the aerogels after hydrophobic modification are able to effectively adsorb common oils and organic solvents spilling on water. Furthermore, the aerogels are compressible, dimension stable and solvent resistive and can be easily regenerated, bringing a great superiority in the comprehensive treatment of multiple contaminations in waterbody. [ABSTRACT FROM AUTHOR]

Abstract: Microgravity has a unique effect on biological organisms. Organs exposed to microgravity display cellular senescence, a change that resembles the aging process. To directly investigate the influence of simulated microgravity on neuronal original rat PC12 cells, we used a rotary cell culture system that simulates the microgravity environment on the earth. We found that simulated microgravity induced partial G1 phase arrest, upregulated senescence-associated β-galactosidase (SA-β-gal) activity, and activated both p53 and p16 protein pathways linked to cell senescence. The amount of reactive oxygen species (ROS) was also increased. The activity of intracellular antioxidant enzymes, such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), was all significantly increased at 12h after the microgravity onset, yet decreased at 96h. Furthermore, concomitant block of ROS by the antioxidant N-acetylcysteine significantly inhibited the microgravity-induced upregulation of SA-β-gal activity. These results suggest that exposure to simulated microgravity induces cellular senescence in PC12 cells via an increased oxidant stress. [Copyright &y& Elsevier]

• Viability of Cryptosporidium oocysts is a risk factor for the waterborne pathogen. • Oocyst viability also measures deactivation efficiency in water treatments. • Inviable oocysts in water may retain structure and DNA for weeks to months. • Commonly used microscopic/PCR methods cannot measure or quantify oocyst viability. • New assays are developed and validated to quantify viable oocysts that infect humans. While waters might be contaminated by oocysts from >40 Cryptosporidium species, only viable oocysts of C. parvum and C. hominis truly pose the main health risk to the immunocompetent population. Oocyst viability is also an important but often neglected risk factor in monitoring waterborne parasites. However, commonly used methods in water monitoring and surveys cannot distinguish species (microscopic observation) or oocyst viability (PCR), as dead oocysts in water could retain gross structure and DNA content for weeks to months. Here, we report new TaqMan qRT-PCR/qPCR assays for quantitative detection of viable C. parvum and C. hominis oocysts. By targeting a hypothetical protein-encoding gene cgd6_3920 that is highly expressed in oocysts and variable between species, the qRT-PCR/qPCR assays achieve excellent analytical specificity and sensitivity (limit of quantification [LOQ] = 0.25 and 1.0 oocyst/reaction). Using calibration curves, the number and ratio of viable oocysts in specimens could be calculated. Additionally, we also establish a TaqMan-18S qPCR for cost-effective screening of pan- Cryptosporidium -positive specimens (LOQ = 0.1 oocyst/reaction). The assay feasibility is validated using field water (N = 43) and soil (79) specimens from 17 locations in Changchun, China, which detects four Cryptosporidium species from seven locations, including three gp60 -subtypes (i.e., IIdA19G1, IIdA17G1 and IIdA24G2) of C. parvum oocysts showing varied viability ratios. These new TaqMan q(RT)-PCR assays supplement current methods in the survey of waters and other samples (e.g., surfaces, foods and beverages), and are applicable to assessing the efficiency of oocyst deactivation protocols. [Display omitted] [ABSTRACT FROM AUTHOR]