Survival prediction of stomach cancer using expression data and deep learning models with histopathological images.

Accurately predicting patient survival is essential for cancer treatment decision. However, the prognostic prediction model based on histopathological images of stomach cancer patients is still yet to be developed. We propose a deep learning-based model (MultiDeepCox-SC) that predicts overall survival in patients with stomach cancer by integrating histopathological images, clinical data, and gene expression data. The MultiDeepCox-SC not only automatedly selects patches with more information for survival prediction, without manual labeling for histopathological images, but also identifies genetic and clinical risk factors associated with survival in stomach cancer. The prognostic accuracy of the MultiDeepCox-SC (C-index = 0.744) surpasses the result only based on histopathological image (C-index = 0.660). The risk score of our model was still an independent predictor of survival outcome after adjustment for potential confounders, including pathologic stage, grade, age, race, and gender on The Cancer Genome Atlas dataset (hazard ratio 1.555, p = 3.53e-08) and the external test set (hazard ratio 2.912, p = 9.42e-4). Our fully automated online prognostic tool based on histopathological images, clinical data, and gene expression data could be utilized to improve pathologists' efficiency and accuracy (https://yu.life.sjtu.edu.cn/DeepCoxSC).

Identification of differentially expressed genes associated with precocious puberty by suppression subtractive hybridization in goat pituitary tissues.

The aim of this study was to identify genes related to precocious puberty expressed in the pituitary of goats at different growth stages by suppression subtractive hybridization (SSH). The pituitary glands from Jining Gray (JG) goats (early puberty) and Liaoning Cashmere (LC) goats (late puberty) at 30, 90, and 180 days were used in this study. To identify differentially expressed genes (DEGs) in the pituitary glands, mRNA was extracted from these tissues, and SSH libraries were constructed and divided into the following groups: juvenile group (30-JG vs. 30-LC, API), puberty group (90-JG vs. 180-LC, BPI), and control group (90-JG vs. 90-LC, EPI). A total of 60, 49, and 58 DEGs were annotated by 222 Gene Ontology (GO) terms and 75 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Most of the DEGs were significantly enriched in GO terms related to 'structural constituent of ribosome', 'translation' and 'GTP binding', and numerous DEGs were also significantly enriched in KEGG terms related to the Jak-STAT signaling and oocyte meiosis pathways. Candidate genes associated with precocious puberty and sexual development were screened from the SSH libraries. These genes were analyzed to determine if they were expressed in the pituitary tissues of the goats at different growth stages and to identify genes that may influence the hypothalamic-pituitary-gonadal (HPG) axis. In this study, we found precocious puberty-related genes (such as PRLP0, EIF5A, and YWHAH) that may be interesting from an evolutionary perspective and that could be investigated for use in future goat breeding programs. Our results provide a valuable dataset that will facilitate further research into the reproductive biology of goats.

Identifying priority areas for freshwater supply conservation integrating multi-scale freshwater flows.

Identifying priority areas for conservation is an effective measurement for the sustainable provision of ecosystem services (ESs) under threats globally. Although many approaches have been developed to identify conservation priority areas by combining supply and demand of ESs, the integration of ESs flows into the identification still need further exploration. For ESs like freshwater supply services, the processes of freshwater flows across multiple scales are crucial. This study aimed to propose a new study framework to identify priority areas for freshwater supply conservation by integrating the multi-scale (i.e., sub-watershed, tributary, and mainstream) freshwater flows, using the Yangtze River Delta as the study area. The results suggested that spatial mismatches between the supply and demand of freshwater supply services existed at different scales. There were approximately 129, 58, and 55 pairs of freshwater flows in sub-watersheds, tributaries, and mainstreams, respectively, which transported 5.98 × 1010 m3, 2.07 × 1010 m3 and 2.50 × 1010 m3 of freshwater. The results of multi-scale freshwater flows were integrated into conservation target goals, and the identified priority areas for freshwater supply conservation were selected at three scales. The priority areas selected at the sub-watershed scale were the largest. Compared with the traditional method of identifying priority areas without considering freshwater flows, the priority areas identified in this study included both sites with a high supply capacity and sites with a relatively low supply capacity, as they were significant for meeting the local freshwater demand. The increasing understanding of freshwater flows and the integration of the flows for the identification of priority areas for freshwater supply conservation are important for the development of more practical and rational policies or ecological management for the sustainable conservation of ESs.

Do trace metal(loid)s in road soils pose health risks to tourists? A case of a highly-visited national park in China.

Nowadays, more people tend to spend their recreational time in large national parks, and trace metal(loid)s in soils have attracted long-term attention due to their possible harm to human health. To investigate the pollution levels, potential sources and health risks of trace metal(loid)s in road soils, a total of eight trace metal(loid)s (including As, Cd, Cr, Cu, Ni, Pb, Zn and Hg) from 47 soil samples along roads were studied in the Huangshan National Park in Southeast China. The results showed that the concentrations of As, Cd, Pb, Zn and Hg appeared different degrees of pollution compared with their corresponding background values. According to the pollution indices, Hg and Cd were recognized as significant pollutants presenting moderate to high ecological risk. Combining principal component analysis and positive matrix factorization model, the results showed that traffic, industrial, agricultural and natural sources were the potential origins of trace metal(loid)s in this area, with contribution rates of 39.93%, 25.92%, 10.53% and 23.62%, respectively. Non-carcinogenic risks were all negligible, while the carcinogenic risk of As was higher than the limit (1 × 10-6). Moreover, children were more susceptible to trace metal(loid)s by ingestion which appeared to be a more important exposure pathway than dermal contact and inhalation. The contribution rates of different sources to non-carcinogenic risks and carcinogenic risks were similar among children and adults, while traffic and industrial sources have a significant impact on health risks. This study will give more insights to control the environmental risks of trace metal(loid)s in national parks.

Promotion time cure rate model with a neural network estimated nonparametric component.

Promotion time cure rate models (PCM) are often used to model the survival data with a cure fraction. Medical images or biomarkers derived from medical images can be the key predictors in survival models. However, incorporating images in the PCM is challenging using traditional nonparametric methods such as splines. We propose to use neural network to model the nonparametric or unstructured predictors' effect in the PCM context. Expectation-maximization algorithm with neural network for the M-step is used for parameter estimation. Asymptotic properties of the proposed estimates are derived. Simulation studies show good performance in terms of both prediction and estimation. We finally apply our methods to analyze the brain images from open access series of imaging studies data.

Influencing factors of the supply-demand relationships of carbon sequestration and grain provision in China: Does land use matter the most?

The provision of ecosystem services (ESs) such as carbon sequestration and grain provision are critical components to sustainable development. Reaching carbon neutrality generally requires the growing carbon sequestration of forest land, and feeding a growing population needs an expansion of cultivated land. However, limited land resources may lead to a contradiction between the carbon sequestration and grain provision. China has proposed long-term and large-scale land use programs, and exploring whether these land use policies are effective for ES sustainable provision would be instructive for future policy implications. This study integrated multi-source data in the socioecological dimension to determine the extent by which land use and land use change influence the supply-demand mismatches of carbon (carbon sequestration and emission) and grain (grain provision and consumption) in China at the provincial level. The result showed that the total quantity of carbon emissions surpassed carbon sequestration and the grain provision could cover the consumption from 2000 to 2015. Spatially, southeastern coastal provinces had higher grain deficits and northeast provinces had higher carbon deficits. This study further detected the influencing factors of the mismatches between the supply and demand of the two ESs. Excluding land use factors, our results showed that social factors contributed 38% and 47% to the supply-demand mismatches of carbon and grain, respectively, and natural factors contributed 39% and 15%, respectively. During 2000-2005, 2005-2010, and 2010-2015, cropland changes significantly affected grain balance, while forest land changes did not significantly affect carbon balance. These results indicated that cropland protections are vital to food safety, and carbon emission reductions should be the focus for carbon balance. Finally, this study makes policy suggestions for land use and ecosystem management, and a future research framework was proposed to help mitigate ES supply-demand imbalance.

Different responses to glucose overload between two strains of largemouth bass (Micropterus salmoides).

In order to improve the glucose utilization capacity of largemouth bass (Micropterus salmoides), responses to glucose overload between two strains (Y: breeding strain; W: wild strain) were compared at 0, 6, 12, and 24 h after glucose injection (1.67 g/kg). The data revealed that plasma glucose in the Y strain (<12 h) recovered faster than in the W strain (12 h), with the Y strain secreted more insulin within 6 h post-injection. Triglyceride (TG) and low-density lipoprotein-cholesterol (VLDL-CH) content in the Y strain increased, peaking at 12 h, then decreased, whereas the W strain's TG content was not affected and VLDL-CH content decreased. The hepatic and muscular fatty acid synthetase, liver x receptor-1, and sterol regulatory element-binding protein expressions were consistent with the TG content change. Both strains' liver and muscle glycogen contents exhibited similar trends to that of the glycogen synthase gene-increasing, then declining, and peaking at 6 and 12 h. The expression levels of hepatic and muscular phosphofructokinase and pyruvate kinase in the Y strain increased, peaking at 12 h. In the W strain, they were suppressed and reached the minimum at 24 h. The mRNA levels of hepatic and muscular phosphoenolpyruvate carboxykinase and glucose-6-phosphatase were enhanced and peaked at 24 h in both strains, hepatic isocitrate dehydrogenase-1, and α-ketoglutarate dehydrogenase complex expression increased after declining, peaking at 12 and 24 h. Two genes in the W strain's muscles showed a similar trend. Both strains' transcriptome results identified seven common functional genes for resistance to hyperglycemia that were involved in the circadian rhythm pathway, which is a suggested key pathway for coping with hyperglycemia. Furthermore, 48 differential genes were identified between the two strains, and these genes were enriched in the TGF-beta and cell cycle signaling pathways, indicating that these pathways may be key factors affecting the differential responses to glucose overload. We conducted a comprehensive comparison of glucose overload molecular responses between two strains of M. salmoides, and the results can provide a promising strategy to improve the glucose utilization capacity of M. salmoides based on advantageous pre-existing traits.

Fabp4 contributes toward regulating inflammatory gene expression and oxidative stress in Ctenopharyngodon idella.

Fatty acid-binding protein (Fabp)-4 is a member of the FABP family. Mammalian fabp4 has been demonstrated to involve in inflammation and immunity, whereas the related data of fish fabp4 remain limited. Therefore, we further investigated the effects of fabp4 on immunity in Ctenopharyngodon idella. The fabp4 sequence spanned 405 bp was cloned first, sharing high identity to fabp4 from other fish and mammals. Fabp4 expression was the highest in the adipose tissue, followed by the heart, muscle, and liver. In vivo, lipopolysaccharide (LPS) triggered the expression of fabp4, toll-like receptor (tlr)-22, interleukin (il)-1ß, and tumor necrosis factor (tnf)-α in the kidney and spleen. In vitro, exposing C. idella CIK cells to LPS decreased their viability, and the expression of fabp4 was also increased by LPS. However, BMS309403, an inhibitor of FABP4, mitigated these effects. Furthermore, treating the cells with LPS or fabp4 overexpression plasmids resulted in reactive oxygen species (ROS) generation and upregulation of inflammatory genes expression, including tlr22, type-I interferon (ifn-1), interferon regulatory factor (irf)-7, tnfα, il-1ß, and interferon-ß promoter stimulator 1. These effects were ameliorated by preincubation with BMS309403. Moreover, incubating the cells with glutathione reduced the production of ROS and the expression of inflammatory genes that were evoked by LPS and plasmid treatments. These results showed that fabp4 acts as a pro-inflammatory molecule via elevating ROS levels, providing a novel understanding of the molecular regulation of innate immunity in teleosts.

A systematic review on antibiotics misuse in livestock and aquaculture and regulation implications in China.

China is one of the largest producers and consumers of antibiotics, and China is a larger producer of livestock farming and aquaculture in the world. The livestock farming and aquaculture industry is a major area of antibiotic misuse, which has caused serious antibiotic residues and environment pollution. The antibiotic residues exceeding the standard may lead to antibiotic resistances in animals or human bodies, which poses a threat to human health. In this context, this study tries to systematically review the current situation of antibiotic misuse in livestock and aquaculture in China, and put forward corresponding regulatiory measures for the central government. Based on the status quo of livestock farming and aquaculture in China, this study reviewed antibiotic misuse in livestock farming and aquaculture and antibiotic resistance in China, introduced China's current policies on antibiotic regulation and the gap between China and developed countries, and analyzed the implications of current regulatory policies on animal health and productivity. At last, we put forward suggestions for the future antibiotic regulation, including strictly implementing the relevant laws and regulations, formulating specific supporting measures, encouraging the research and development of antibiotic substitutes, introducing advanced technologies for supervision and regulation, strengthening the publicity of science popularization and enhancing the public's awareness of the rational use of antibiotics. If these policy recommendations can be implemented, they will significantly promote the regulation of antibiotic abuse.

Variable selection for joint models with time-varying coefficients.

Many clinical studies collect longitudinal and survival data concurrently. Joint models combining these two types of outcomes through shared random effects are frequently used in practical data analysis. The standard joint models assume that the coefficients for the longitudinal and survival components are time-invariant. In many applications, the assumption is overly restrictive. In this research, we extend the standard joint model to include time-varying coefficients, in both longitudinal and survival components, and we present a data-driven method for variable selection. Specifically, we use a B-spline decomposition and penalized likelihood with adaptive group LASSO to select the relevant independent variables and to distinguish the time-varying and time-invariant effects for the two model components. We use Gaussian-Legendre and Gaussian-Hermite quadratures to approximate the integrals in the absence of closed-form solutions. Simulation studies show good selection and estimation performance. Finally, we use the proposed procedure to analyze data generated by a study of primary biliary cirrhosis.

Transcriptome analysis of the effect of bisphenol A exposure on the growth, photosynthetic activity and risk of microcystin-LR release by Microcystis aeruginosa.

Bisphenol A (BPA), one of the most abundant endocrine-disrupting compounds, is frequently detected in diverse aquatic environments, which imposes a substantial burden on the aquatic ecosystem. However, the correlation between BPA levels and the outbreak of a cyanobacterial bloom remains largely unknown. In this study, the cellular and transcriptomic responses to BPA exposure were investigated. Exposure to a high concentration of BPA (50 µM) significantly inhibited the growth of cyanobacterial cells, with the highest inhibition ratio of 51.3%, photosynthesis, and the release of extracellular microcystin-LR (MC-LR) (p < 0.05). However, exposure to low concentrations of BPA (0.1 and 1 µM) also affected these indicators, but the differences were closely related to the growth phase of the cyanobacterial cells. In addition, an imbalance between the antioxidant system and oxidative stress was observed in cyanobacteria under BPA stress. Folate biosynthesis, ABC transporters and ubiquinone and other terpenoid-quinone biosynthesis were the central metabolic pathways triggered by BPA stress. The up-regulated genes, including queC, VTE3 and PsbO were the controller of cellular growth and photosynthesis. The down-regulated genes, including VET4, MlaE and DnaA were potential biomarkers of oxidative damage. The up- and down-regulated genes, including CA, Ppc and CyoE were the main regulators of energy generation. The findings will provide important insights into the role of endocrine disruptors in the frequent outbreak of cyanobacterial blooms.

Are the Water Quality Improvement Measures of China's South-to-North Water Diversion Project Effective? A Case Study of Xuzhou Section in the East Route.

Xuzhou is the hub city of the east route of China's South-to-North Water Diversion (SNWD) project and implemented dozens of measures to ensure the water quality security of the water transmission line. In order to detect the effectiveness of water quality improvement measures, the monthly water quality data of five water quality parameters from 2005 to 2015 of six state-controlled monitoring sites in Xuzhou section were selected for analysis. The results showed that the water quality improved from 2.95 in 2005 to 2.74 in 2015, as assessed by the comprehensive water quality identification index (CWQII), and basically reached the Class III standards of China's Environmental Quality Standard for Surface Water (GB3838-2002) from 2011 to 2015. The trend analysis showed that the decline of ammonia nitrogen (NH3-N) was the most obvious among the five water quality parameters. However, the concentrations of phosphorus (TP) showed significant upward trends at three sites. The positive abrupt change of time series of water quality occurred in 2009-2011. The identification of influencing factors of water quality changes by multivariate statistical methods found that the urbanization factor accompanied by a decrease in agricultural nonpoint source pollution emissions and the enhancement of wastewater treatment capacity, the closure of factories with substandard emissions and precipitation were the major influencing factors of most water quality parameters, which confirmed the effectiveness of measures for water quality improvement in Xuzhou.

Risk Assessment and Source Apportionment of Soil Heavy Metals under Different Land Use in a Typical Estuary Alluvial Island.

Understanding the environmental risks of soil heavy metals (HMs) and identifying their main sources are the essential prerequisites for the prevention and management of soil pollution. Based on a detailed survey of soil HMs (Cu, Cr, Ni, Zn, Pb, Cd, As and Hg) from different land use types (including agricultural land, construction land, wetland, and forest land) in an estuary alluvial island, the environmental risk and source apportionment of soil HMs were investigated. Altogether, 117 soil samples were taken in the study area to appraise the soil HMs environmental risk by using the geo-accumulation index (Igeo), potential ecological risk index (RI), and human health risk assessment (HRA) and to identify its main sources by using positive matrix factorization (PMF) model. The average concentrations of soil HMs (except As) surpassed their reference background values in China. There were no significant differenced in the mean concentrations of HMs in different land use types, except that the Hg concentration in the construction land was significantly higher than that in others. The results of Igeo showed that Cd pollution was unpolluted to moderately polluted, and that the others were unpolluted. The potential ecological risk level for Cd and Hg was "moderated potential risk", while for Cu, Cr, Ni, Zn, Pb and As was "low potential risk". Higher contamination was distributed at the west-central area. The results of the HRA indicated that the non-carcinogenic risk and the carcinogenic risk that human beings suffered from HMs in different land uses were insignificant. To more accurately identify the sources of soil HMs, the PMF model coupled with the GIS-spatial analysis was applied. The results showed that agricultural activities, natural source, industrial discharge and river transportation, and atmosphere deposition were the main determining factors for the accumulation of soil HMs in the study area, with the contribution rate of 24.25%, 23.79%, 23.84%, and 28.12%, respectively. The study provides an underlying insight needed to control of the soil HM pollutions for an estuary alluvial island.

Bioaccumulation and health risk assessment of heavy metals to bivalve species in Daya Bay (South China Sea): Consumption advisory.

Bivalves are one of the key components of the biogeochemical cycle in the marine system, and respond to heavy metal (HM) sensitively as filter feeders. To determine relationship of HMs in edible bivalve and seawater and HM effects on human health when digesting bivalves, HMs were analyzed in bivalves and seawater. The results showed that the mean HM concentrations in bivalves decreased in the order of Zn > Cu > Cr > Pb > As > Cd > Hg. Generally, all the bioconcentration factor values of bivalves were higher than 100, suggesting that bivalves have a high bioaccumulation ability. Nonmetric multidimensional scaling analysis indicated that all bivalves have a high bioaccumulation capacity for Cu and Zn. It was found that there are health risks associated with consuming bivalves, and children are more vulnerable than adults. Finally, the maximum allowable consumption rates of non-carcinogenic and carcinogenic risk were determined. These results provide the underlying insights needed to guide the consumption of seafood.

[Spatial response of lake water quality to multi-scale landscape pattern of lakeside zone in agricultural watershed].

Understanding the response of water quality in lake to landscape pattern at different spatial scales in agricultural watershed is of great significance to water quality management. In this study, we classified seven riparian buffer zones of lakeside zone by ArcGIS and RS in the Honghu Lake, according to the five functional areas. The landscape metrics were analyzed at multiple buffer widths using Fragstats software. Mathematical statistical methods and models such as redundancy analysis were used to explore spatial relationship between water quality and landscape patterns. Results showed that: 1) The effect of landscape patterns on water quality was scale-dependent at multiple buffer widths. The highest total explanatory power between landscape characteristics and water quality was found at the 200 m buffer width, accounting for 86.1% of the total, which was the most effective spatial scale affecting water quality. 2) The landscape configuration (e.g., largest patch index, patch density) was more associated with water quality than landscape composition (e.g., the percent of landscape and evenness index). 3) The impacts of different landscape types on water quality varied. Agriculture land, affected by topography and cultivation mode, was the main influencing factor on the degradation of water quality at smaller buffer widths from 100 m to 500 m. Forests with higher density and area had more purification effect on water pollutants at the wider buffer widths from 1000 m to 5000 m. The impacts of grassland on water quality was similar with that of forests, but densely distributed urban land contributed to water quality degradation at the same buffer widths. This study could provide scientific reference for water quality management and landscape planning of lake basin in agricultural areas.

Detecting the response of bird communities and biodiversity to habitat loss and fragmentation due to urbanization.

Birds are considered a good model for indicators of biodiversity response to habitat variations, as they are very sensitive to environmental change. However, continuous observations of habitat alterations from undisturbed landscapes to human-dominated ones, as well as the associated effects on bird biodiversity, are lacking. In this study, New Jiangwan Town in Shanghai, China was selected to illustrate the response of bird species, and thus biodiversity, to habitat loss and fragmentation. Land use/land cover (LULC) data and bird records from 2002 to 2013 were collected and analyzed. The results suggested that, due to urban sprawl, the area of wetland and shrub land had dropped by 82.4% and 87.3% by the end of 2013. Four different urbanization stages were identified in terms of the spatio-temporal variations in the landscape. To measure bird biodiversity, species richness and relative abundance were calculated, and they could account for the overall trend in biodiversity but might mask the process of species replacement. As an indicator of biodiversity accounting, the mean species abundance (MSA) of the original species would not include exotic or invasive species in its calculation, and its value decreased from 100% to 76.8% to 52.2% to 24.5% in the four corresponding stages. Finally, suggested by redundant analysis, the effects of habitat loss and fragmentation on bird biodiversity differed in various bird communities, and the area and connectivity of wetlands were the most significant variables. Our findings could provide important information to inform bird biodiversity protection and habitat restoration.

"APEC blue"--The effects and implications of joint pollution prevention and control program.

To ensure good air quality in Beijing during Asia-Pacific Economic Cooperation (APEC) China 2014, Beijing and its neighboring five provinces and the associated cities were combined under the Joint Prevention and Control of Atmospheric Pollution (JPCAP) program, which implemented rigorous cooperative emission reduction measures. The program was a unique and large-scale artificial experiment that showed that such measures can achieve excellent results, and it led to the popular "APEC blue" catchphrase (i.e., Beijing's skies became blue as pollution levels decreased). This artificial experiment provided the means to effectively conduct JPCAP strategies in the future. Accordingly, our research focused on the characteristics of the six primary pollutants in Beijing. We found that the JPCAP measures directly reduced concentrations of all pollutants except O3. Through correlation analysis, we found that the band distribution of the cities with strong correlations in PM2.5 and PM10 concentrations was affected by wind conditions. Therefore, JPCAP measures should account for specific seasonal and climatic conditions. Based on cluster analysis using the results from the correlation analysis, we divided 13 cities within a 300-km radius of Beijing into different groups according to the similarity of their PM2.5 and PM10 correlation coefficients. For JPCAP measures relevant to PM2.5 and PM10, we found differences in the degrees of collaboration among cities. Therefore, depending upon the pollutant type, the JPCAP strategy should account for the cities involved, the scope of the core area, and the optimal cities to involve in the collaborative efforts based on cost-effectiveness and collaborative difficulty among the involved cities.

A cooperative reduction model for regional air pollution control in China that considers adverse health effects and pollutant reduction costs.

How to effectively control severe regional air pollution has become a focus of global concern recently. The non-cooperative reduction model (NCRM) is still the main air pollution control pattern in China, but it is both ineffective and costly, because each province must independently fight air pollution. Thus, we proposed a cooperative reduction model (CRM), with the goal of maximizing the reduction in adverse health effects (AHEs) at the lowest cost by encouraging neighboring areas to jointly control air pollution. CRM has two parts: a model of optimal pollutant removal rates using two optimization objectives (maximizing the reduction in AHEs and minimizing pollutant reduction cost) while meeting the regional pollution control targets set by the central government, and a model that allocates the cooperation benefits (i.e., health improvement and cost reduction) among the participants according to their contributions using the Shapley value method. We applied CRM to the case of sulfur dioxide (SO2) reduction in Yangtze River Delta region. Based on data from 2003 to 2013, and using mortality due to respiratory and cardiovascular diseases as the health endpoints, CRM saves 437 more lives than NCRM, amounting to 12.1% of the reduction under NCRM. CRM also reduced costs by US $65.8×106 compared with NCRM, which is 5.2% of the total cost of NCRM. Thus, CRM performs significantly better than NCRM. Each province obtains significant benefits from cooperation, which can motivate them to actively cooperate in the long term. A sensitivity analysis was performed to quantify the effects of parameter values on the cooperation benefits. Results shown that the CRM is not sensitive to the changes in each province's pollutant carrying capacity and the minimum pollutant removal capacity, but sensitive to the maximum pollutant reduction capacity. Moreover, higher cooperation benefits will be generated when a province's maximum pollutant reduction capacity increases.

Screening and Evaluation of the Bioremediation Potential of Cu/Zn-Resistant, Autochthonous Acinetobacter sp. FQ-44 from Sonchus oleraceus L.

The quest for new, promising and indigenous plant growth-promoting rhizobacteria and a deeper understanding of their relationship with plants are important considerations in the improvement of phytoremediation. This study focuses on the screening of plant beneficial Cu/Zn-resistant strains and assessment of their bioremediation potential (metal solubilization/tolerance/biosorption and effects on growth of Brassica napus seedlings) to identify suitable rhizobacteria and examine their roles in microbes-assisted phytoremediation. Sixty Cu/Zn-resistant rhizobacteria were initially isolated from Sonchus oleraceus grown at a multi-metal-polluted site in Shanghai, China. From these strains, 19 isolates that were all resistant to 300 mg⋅L-1 Cu as well as 300 mg⋅L-1 Zn, and could simultaneously grow on Dworkin-Foster salt minimal medium containing 1-aminocyclopropane-1-carboxylic acid were preliminarily selected. Of those 19 isolates, 10 isolates with superior plant growth-promoting properties (indole-3-acetic acid production, siderophore production, and insoluble phosphate solubilization) were secondly chosen and further evaluated to identify those with the highest bioremediation potential and capacity for bioaugmentation. Strain S44, identified as Acinetobacter sp. FQ-44 based on 16S rDNA sequencing, was specifically chosen as the most favorable strain owing to its strong capabilities to (1) promote the growth of rape seedlings (significantly increased root length, shoot length, and fresh weight by 92.60%, 31.00%, and 41.96%, respectively) under gnotobiotic conditions; (2) tolerate up to 1000 mg⋅L-1 Cu and 800 mg⋅L-1 Zn; (3) mobilize the highest concentrations of water-soluble Cu, Zn, Pb, and Fe (16.99, 0.98, 0.08, and 3.03 mg⋅L-1, respectively); and (4) adsorb the greatest quantities of Cu and Zn (7.53 and 6.61 mg⋅g-1 dry cell, respectively). Our findings suggest that Acinetobacter sp. FQ-44 could be exploited for bacteria-assisted phytoextraction. Moreover, the present study provides a comprehensive method for the screening of rhizobacteria for phytoremediation of multi-metal-polluted soils, especially those sewage sludge-amended soils contaminated with Cu/Zn.