Potential pathogenic microorganisms in rural wastewater treatment process: Succession characteristics, concentration variation, source exploration, and risk assessment.

Pathogenic microorganisms can cause infection, sepsis, and other diseases in humans. Although municipal wastewater plants are important sources and sinks for potential pathogenic microorganisms, data on rural wastewater treatment processes are limited. The proximity of rural wastewater facilities to human settlements and the trend toward wastewater resourcing could pose risks to humans. Here, a typical village in southern China was selected to analyze potential pathogenic microorganisms in wastewater, sewage sludge, and aerosols during the collection, treatment, and discharge of domestic wastewater. The succession characteristics and concentration variations of potential pathogenic microorganisms throughout the wastewater treatment process were identified using high-throughput sequencing and culture methods. Bacteria-associated health risks in facility aerosols were estimated based on average daily dose rates from inhalation and dermal exposure. Lower amounts of pathogenic bacteria and pathogenic fungi were detected in the effluent of the 1-ton treatment scale and the 10-ton treatment scale facilities, compared to those in the influent. Pathogen effluent concentrations were significantly lower than influent concentrations after treatment in rural wastewater facilities. 16 and 29 potential pathogenic bacteria and fungi were detected in aerosols from wastewater treatment facilities, respectively. Furthermore, the potential pathogen concentrations were higher than those in the background air. Aerobic units are the main source of pathogen emissions from aerosols. There were 42 potential pathogenic bacteria and 34 potential pathogenic fungi in the sewage sludge. Biochemical units were the main source of potential pathogens in sewage sludge, and more potential airborne pathogens originated from wastewater. In rural wastewater resourcing processes with greater pollutant exposure, the effluent of rural wastewater treatment facilities (WWTFs), downstream rivers, and facility aerosols, could be important potential sources of microbial risk. Inhalation is the main pathway of human exposure to airborne bacteria. Therefore, more attention should be focused on microbiological risk in rural wastewater treatment processes.

The lesser of two evils: Assessing the public acceptance of AI thermal facial recognition during the COVID-19 crisis.

AI thermal facial recognition (AITFR) has been rapidly applied globally in the fight against Coronavirus disease 2019 (COVID-19). However, AITFR has also been accompanied by a controversy regarding whether the public accepts it. Therefore, it is necessary to assess the acceptance of AITFR during the COVID-19 crisis. Drawing upon the theory of acceptable risk and Siegrist's causal model of public acceptance (PA), we built a combined psychological model that included the perceived severity of COVID-19 (PSC) to describe the influencing factors and pathways of AITFR acceptance. This model was verified through a survey conducted in Xi'an City, Shaanxi Province, China, which collected 754 valid questionnaires. The results show that (1) COVID-19 provides various application scenarios for AI-related technologies. However, the respondents' trust in AITFR was found to be very low. Additionally, the public appeared concerned about the privacy disclosure issue and the accuracy of the AITFR algorithm. (2) The PSC, social trust (ST), and perceived benefit (PB) were found to directly affect AITFR acceptance. (3) The PSC was found to have a significant positive effect on perceived risk (PR). PR was found to have no significant effect on PA, which is inconsistent with the findings of previous studies. (4) The PB were found to be a stronger mediator of the indirect effect of the PSC on ST induced by AITFR acceptance.

Total petroleum hydrocarbons and influencing factors in co-composting of rural sewage sludge and organic solid wastes.

Co-composting is an efficient strategy for collaborative disposal of multiple organic wastes in rural areas. In this study, we explored the co-composting of rural sewage sludge and other organic solid wastes (corn stalks and kitchen waste), with a focus on the variation of total petroleum hydrocarbons (TPH) during this process. 12% corn-derived biochar was applied in the composting (BC), with no additives applied as the control treatment (CK). The TPH contents of piles after composting ranged from 0.70 to 0.74 mg/g, with overall removal efficiencies of 35.6% and 61.1% for CK and BC, respectively. The results indicate that the addition of 12% biochar increased the rate of TPH degradation and accelerated the degradation process. 16s rDNA high-throughput sequencing was applied to investigate the biodiversity and bacterial community succession during the composting process. Diverse bacterial communities with TPH degradation functions were observed in the composting process, including Acinetobacter, Flavobacterium, Paenibacillus, Pseudomonas, and Bacillus spp. These functional bacteria synergistically degraded TPH, with cooperative behavior dominating during composting. Biochar amendment enhanced the microbial activity and effectively promoted the biodegradation of TPH. The physicochemical properties of the compost piles, including environmental factors (pH and temperature), nutrients (nitrogen, phosphorus, potassium), and humic substances produced in composting (humic acids and fulvic acids), directly and indirectly affected the variation in TPH contents. In conclusion, this work illustrates the variation in TPH content and associated influencing factors during co-composting of rural organic solid wastes, providing valuable guidance toward the further optimization of rural organic waste management.

Effect of ultra-early intervention of NDT therapy on nerve and motor development in infants at high risk of cerebral palsy.

INTRODUCTION: The aim of the study was to investigate the effect of ultra-early intervention of nerve and motor development in infants at high risk of cerebral palsy. MATERIAL AND METHODS: One hundred and twenty cases of infants born in The Affiliated Hospital of Harbin Medical University from January 2017 to January 2019 and diagnosed with high risk of cerebral palsy were included in the observation group. In addition, 120 cases of infants at high risk of cerebral palsy (three to five months old) who were admitted to this hospital during the same period were included in the control group, and 120 healthy infants born in the same hospital were included in the healthy group. Intervention was performed on the observation group after diagnosis (within seven days of birth), mainly using neurodevelopmental therapy (NDT). Children in the control group underwent intervention after diagnosis (at three to five months old) using the same measures. The healthy group underwent no intervention. Changes in various indicators were compared among the observation group, healthy group, and control group. RESULTS: At baseline and at three months, the developmental quotient (DQ) at all functional areas, total DQ, and GESELL development scale (GDS) scores were significantly lower in the observation and control groups than in the healthy group ( p < 0.05). At six months, 12 months, 18 months, and 24 months, the DQ at all functional areas, total DQ, and GDS (adaptability, gross motor, fine motor, language, personal social interaction) scores in the observation and control groups were significantly lower than those in the healthy group ( p < 0.05). However, the observation group scores were significantly higher than the control group scores ( p < 0.05). In the observation group, the normalisation rate was higher than in the control group, and the incidence rate of cerebral palsy and full developmental delay was lower than in the control group ( p < 0.05). CONCLUSIONS: Ultra-early diagnosis and NDT intervention can significantly accelerate the motor development of infants at high risk of cerebral palsy. The earlier, the better. Ultra-early intervention can promote the normalisation of infants at high risk of cerebral palsy and significantly reduce the risk of progression to cerebral palsy.

Succession and change of potential pathogens in the co-composting of rural sewage sludge and food waste.

Composting is an effective way to prevent and control the spread of pathogenic microorganisms which could put potential risk to humans and environment, from rural solid waste, especially sewage sludge and food waste. In the study, we aim to analyze the changes of pathogenic bacteria during the co-composting of rural sewage sludge and food waste. The results showed that only 27 pathogenic bacteria were detected after composting, compared to 50 pathogenic bacteria in the raw mixed pile. About 74% of pathogen concentrations dropped below 1000 copies/g after composting. Lactobacillus, Bacillus, Paenibacillus and Comamonas were the core pathogenic bacteria in the compost, of which concentrations were all significantly lower than that in the raw mixed pile at the end of composting. The concentration of Lactobacillus decreased to 3.03 × 103 copies/g compared to 0 d with 1.25 × 109 copies/g by the end of the composting, while that of Bacillus, Paenibacillus and Comamonas decreased to 2.77 × 104 copies/g, 2.13 × 104 copies/g and 3.38 × 102 copies/g, respectively, with 1.26 × 107 copies/g, 4.71 × 106 copies/g, 1.69 × 108 copies/g on 0 d. Redundancy analysis (RDA) indicated that physicochemical factors and substances could affect the changes of pathogenic bacteria during composting, while temperature was the key influencing factor. In addition, certain potential pathogenic bacteria, such as Bacteroides-Bifidobacterium, show statistically strong and significant co-occurrence during composting, which may increase the risk of multiple infections and also influence their distribution. These findings provide a theoretical reference for biosafety prevention and control in the treatment and disposal of rural solid waste.

Knockdown of lncRNA-NEAT1 expression inhibits hypoxia-induced scar fibroblast proliferation through regulation of the miR-488-3p/COL3A1 axis.

Long non-coding (lnc)RNA nuclear-enriched transcripts 1 (NEAT1) has been demonstrated to be involved in the inhibition of hypoxia-induced scar fibroblast proliferation, but the specific mechanism remains undetermined. The present study found that with the decrease of oxygen concentration, lncRNA NEAT1 was upregulated in hypoxia-induced scar fibroblasts, which promoted the mRNA and protein expression levels of collagen (COL)-I, COL-III and α-smooth muscle actin, thereby suppressing hypoxia-induced scar fibroblasts proliferation. In addition, the microRNA (miR)-488-3p/COL3A1 axis was involved in lncRNA NEAT1's regulation of the proliferation of hypoxia-induced scar fibroblasts. In conclusion, the knockdown of lncRNA-NEAT1 expression can inhibit hypoxia-induced scar fibroblasts proliferation through regulation of the miR-488-3p/COL3A1 axis, which will provide a novel therapeutic target for the treatment of hypertrophic scars.

What catalyzes the proactive recovery of peasants from the COVID-19 pandemic? A livelihood perspective in Ningqiang County, China.

The livelihood recovery strategy is utilized for peasants during the COVID-19 pandemic. This strategy serves a salient role to help them recover from the relevant hazardous impacts. Disaster risk has been a major concern among hazards for the increasing likelihood of exposure and vulnerability, especially in the process of poverty alleviation in China. However, few studies have discussed the factors and mechanisms that influence peasants to adopt livelihood recovery strategies in the context of the COVID-19 pandemic in China. Based on a case study of Ningqiang County, China, this study explores the mechanisms that catalyze the proactive recovery of peasants from the COVID-19 pandemic from a livelihood perspective. Methodologically, the study proposes a framework that integrates the modified pressure-state-response (PSR) framework and the sustainable livelihoods approach (SLA), and it employs structure equation modeling (SEM) approach to examine how specific factors affect peasants to proactively adopt livelihood strategies to recover from the COVID-19 pandemic. The results indicate that the COVID-19 pressure significantly increases the risk perception of peasants and decreases their livelihood capital. Further, the decreased livelihood capital, the improvement of risk perception and supportive policy will promote peasants to adopt livelihood recovery strategies. Moreover, the results specify that risk perception and supportive policy mediate the relation between livelihood capital and recovery strategy. The findings will be beneficial for policymakers and researchers to understand the mechanisms that peasants adopt livelihood strategies to recover from disasters, and can serve as references for formulating disaster risk reduction and resilience policies.

Variation and factors on heavy metal speciation during co-composting of rural sewage sludge and typical rural organic solid waste.

In this study, a co-composting of rural organic solid waste (rural sewage sludge, kitchen waste and corn stalks) was conducted to analyze the variation of heavy metals (As, Cu, Cr, Ni, Pb, Hg, and Zn) and their major influencing factors. During composting, significant changes were observed in the total contents of heavy metals (p < 0.01): the total concentrations of As, Cu, Hg, Pb and Zn increased by 7.5%, 54.1%, 26.3%, 15.8%, and 34.2%, whereas that of Cr and Ni decreased by 71.3% and 33.4%, respectively. Heavy metals were mainly bound to the oxidizable and residual fractions. Spearman and Redundancy analysis (RDA) indicated that substances were significantly correlated with the changes in speciation of heavy metals, among all the factors, while pH and temperature were the dominating environmental influencing parameters. Several metal-resistant bacterial genera (Pseudomonas, Paenibacillus, Bacillus, Acinetobacter, Desulfovibrio, and Ochrobactrum, etc) were observed, with significant explanatory capacity for the changes in heavy metals. Composting showed a poor effect on heavy metal passivation, except for that of As. After composting, the heavy metal contents were consistent with the application standards. The evaluation of potential ecological risk showed a high cumulative ecological risk (336.9) of heavy metals. This study provides technical support and practical information for the disposal and safe recycling for rural organic solid waste.

The efficiency of provincial government health care expenditure after China's new health care reform.

OBJECTIVE: We aim to estimate the total factor productivity and analyze factors related to the Chinese government's health care expenditure in each of its provinces after its implementation of new health care reform in the period after 2009. MATERIALS AND METHODS: We use the Malmquist DEA model to measure efficiency and apply the Tobit regression to explore factors that influence the efficiency of government health care expenditure. Data are taken from the China statistics yearbook (2004-2020). RESULTS: We find that the average TFP of China's 31 provincial health care expenditure was lower than 1 in the period 2009-2019. We note that the average TFP was much higher after new health care reform was implemented, and note this in the eastern, central and western regions. But per capita GDP, population density and new health care reform implementation are found to have a statistically significant impact on the technical efficiency of the provincial government's health care expenditure (P<0.05); meanwhile, region, education, urbanization and per capita provincial government health care expenditure are not found to have a statistically significant impact. CONCLUSION: Although the implementation of the new medical reform has improved the efficiency of the government's health expenditure, it is remains low in 31 provinces in China. In addition, the government should consider per capita GDP, population density and other factors when coordinating the allocation of health care input. SIGNIFICANCE: This study systematically analyzes the efficiency and influencing factors of the Chinese government's health expenditure after it introduced new health care reforms. The results show that China's new medical reform will help to improve the government's health expenditure. The Chinese government can continue to adhere to the new medical reform policy, and should pay attention to demographic and economic factors when implementing the policy.

Microbial aerosol particles in four seasons of sanitary landfill site: Molecular approaches, traceability and risk assessment.

Landfill sites are regarded as prominent sources of bioaerosols for the surrounding atmosphere. The present study focused on the emission of airborne bacteria and fungi in four seasons of a sanitary landfill site. The main species found in bioaerosols were assayed using high-throughput sequencing. The SourceTracker method was utilized to identify the sources of the bioaerosols present at the boundary of the landfill site. Furthermore, the health consequences of the exposure to bioaerosols were evaluated based on the average daily dose rates. Results showed that the concentrations of airborne bacteria in the operation area (OPA) and the leakage treatment area (LTA) were in the range of (4684 ± 477)-(10883 ± 1395) CFU/m3 and (3179 ± 453)-(9051 ± 738) CFU/m3, respectively. The average emission levels of fungal aerosols were 4026 CFU/m3 for OPA and 1295 CFU/m3 for LTA. The landfill site received the maximum bioaerosol load during summer and the minimum during winter. Approximately 41.39%- 86.24% of the airborne bacteria had a particle size of 1.1 to 4.7 µm, whereas 48.27%- 66.45% of the airborne fungi had a particle size of more than 4.7 µm. Bacillus sp., Brevibacillus sp., and Paenibacillus sp. were abundant in the bacterial population, whereas Penicillium sp. and Aspergillus sp. dominated the fungal population. Bioaerosols released from the working area and treatment of leachate were the two main sources that emerged in the surrounding air of the landfill site boundary. The exposure risks during summer and autumn were higher than those in spring and winter.

Examining resilience of disaster response system in response to COVID-19.

We examine the COVID-19 response in China by conceptualizing resilience from the complex adaptive system perspective, including a discussion of the factors contributing to the resilience of the disaster response system. Methodologically, a network-based model was employed to describe the disaster response system. In addition to a traditional network analysis, the dynamics network analysis was conducted to assess the evolution of the disaster response system with a time slice analysis. This study presents theoretical and practical contributions to the field of disaster management by utilizing the complex adaptive system perspective and investigating context-specific resilience of a disaster response system.

Risk Information Seeking Behavior in Disaster Resettlement: A Case Study of Ankang City, China.

In 2011, the Chinese government launched a disaster mitigation and preparedness program called the Resettlement of South Shaanxi (RSS). Due to the wide geographical scope and complex interests, the possibility of conflicts was increased during and after resettlement. Efficient risk communication improves the supply of information about risks and meets the risk-related information needs of individuals. Using the risk information seeking and processing (RISP) model, this research applied a structural equation model and survey with a structured questionnaire to study ways to improve risk communication in disaster resettlement. A total of 616 valid questionnaires were provided by study respondents in resettlement sites in Ziyang County, Ankang City, Shaanxi Province. The results indicated the following: (1) the public's information seeking behavior relies more on village committees and village officials than other channels. Emerging information channels, such as Weibo and WeChat (social media applications in China), do not play leading roles in disseminating risk information. (2) There are differences between the information channels used by residents and the channels that residents believe the most. (3) Relevant channel beliefs, information sufficiency, perceived hazard characteristics, and self-efficacy directly influence risk information seeking behavior. However, the capacity to gather information has non-significant direct influences on information seeking behavior. (4) Perceived hazard characteristics and self-efficacy drive risk information seeking behavior in both direct and indirect ways through information sufficiency.

Effects of chitosan combined with ε-polylysine coating on flavor and texture quality of Chinese shrimp during refrigerated storage.

We investigated the effects of chitosan (CH) combined with ε-polylysine (ε-PL) on the flavor and texture quality of Chinese shrimp refrigerated for 12 days. Shrimp samples were subjected to three preservation treatments (ε-PL, CH, and CH + Îµ-PL) and a control treatment. Sensory characteristics, total volatile basic nitrogen (TVB-N), adenosine triphosphate (ATP)-related compounds, K-values, volatile components, and texture were regularly assessed. The results showed that the sensory characteristics were effectively maintained, the increases in TVB-N, hypoxanthine, and K-value were delayed, and the putrid compounds were reduced by coating, especially with the chitosan combined with ε-polylysine. Treatment with chitosan combined with ε-polylysine was also shown to be a more effective preservation method for maintaining the texture quality of Chinese shrimp compared to treatment with ε-PL or CH alone. Therefore, this technique was demonstrated to be a promising method for maintaining the flavor and texture quality of Chinese shrimp during refrigerated storage.

[Particle Size Distribution and Population Characteristics of Airborne Bacteria Emitted from a Sanitary Landfill Site].

Sanitary landfill is a commonly-used method for solid waste disposal. In the process of landfilling, e. g. dumping, stacking, pushing, and compacting, a large number of bioaerosols with pathogenic bacteria will be generated. That can result in air pollution and significant harm to human health if these pathogens are released into the air. Sampling sites were set up in a domestic waste sanitary landfill in North China to collect airborne bacteria in the air. Airborne bacteria, particle size distributions, and populations were analyzed, and the influence of meteorological parameters (temperature, relative humidity (RH), and wind speed (WS)) on the emission of airborne bacteria was also investigated. Results showed that the concentrations of airborne bacteria in the working area and the coverage area were (5437±572) CFU·m-3 and (2707±396) CFU·m-3, respectively. The emission level in the leachate treatment area was the highest, with an average of 9460 CFU·m-3. The concentration of airborne bacteria showed clear seasonal variation, being was much higher in summer than that in the other seasons. Redundancy analysis (RDA) demonstrated that RH, temperature, and WS affected the number of airborne bacteria in the air. The peaks in the airborne particle size distribution were 2.1-4.7 µm in the working area and 0.65-2.1 µm in the coverage area. Most of the airborne bacteria released from the leachate treatment processes were larger than 4.7 µm. Moraxellaceae, Bacillus aerius, Arcobacter, and Aeromonas were potential or opportunistic pathogens detected from the airborne bacteria samples. Effective measures should be taken to reduce the amount of bacterial aerosol emitted to the air in landfill working areas and in the leachate of treatment areas. Operators of landfill machinery and leachate treatment facilities should consider personal protection measures and should reduce their exposure to microbial aerosols in order to prevent disease.

Evaluation of the secondary structures of protein in the extracellular polymeric substances extracted from activated sludge by different methods.

The changes of protein secondary structures in the extracellular polymeric substances (EPS) extracted from activated sludge by four different methods were studied by analyzing the amide I region (1700-1600 cm-1) of the Fourier transform infrared spectra and model protein test. The results showed the molecular weight distribution of organic matter extracted by centrifugation, heating and cation exchange resin (CER) was similar, while the EPS extracted by centrifugation (Control) and CER had similar fluorescent organic matter. The protein secondary structures of extracted EPS by the four methods were different. The similarities of protein secondary structures between the EPS extracted by CER with the Control were the highest among the four extracted EPS. Although the EPS yield extracted by formaldehyde + NaOH method were the highest, its protein secondary structures had the lowest similarity with those extracted by the Control. Additionally, the effects of centrifugation and CER extraction on the secondary structures of bovine serum albumin were also lower than that of other extraction processes. CER enables the second maximum extraction of EPS and maximum retention of the original secondary structure of proteins.

New insights into the effect of thermal treatment on sludge dewaterability.

The changes of the sludge dewaterability in different thermal treatments and the factors influencing these changes were examined in this study. The experimental results showed that the sludge dewaterability deteriorated by the thermal pretreatment with temperature range from 20 to 170 °C, but the deterioration decreased above a certain temperature threshold (120-150 °C). The factors which affected the dewaterability of thermal-treated sludge in two temperature ranges (20-105 °C and 105-170 °C) were different. The dewaterability of thermal-treated sludge was influenced by the protein, humic acid, and polysaccharide contents of different extracellular polymeric substance fractions and the molecular distribution and fluorescence intensity of tightly bound extracellular polymeric substance in the range from 20 to 105 °C. From 105 to 170 °C, while, the thermal-treated sludge dewaterability was influenced mainly by the α-helix of protein in soluble extracellular polymeric substance. These experimental results provide a new insight into the effect of thermal treatment on sludge dewaterability, which will help guide subsequent research.

Effects of aeration on microbes and intestinal bacteria in bioaerosols from the BRT of an indoor wastewater treatment facility.

The generation and emission of airborne bacteria from a biochemical reaction tank (BRT) for wastewater treatment was investigated by altering the aeration rate. The levels of bioaerosols increased from 715 ±â€¯69 to 1597 ±â€¯135 CFU/m3 (total airborne bacteria) and from 78 ±â€¯6 to 359 ±â€¯18 CFU/m3 (intestinal bacteria) as the aeration rate increased from 0.3 to 1.2 m3/h. Most airborne bacteria were attached to particles smaller than 4.7 µm at an aeration rate of 0.3 m3/h. They were found attached to larger particles (>4.7 µm) when the aeration rate increased to 1.2 m3/h. A similar phenomenon was observed for intestinal bacteria. The high-throughput sequencing technique was used to assay the microbial populations of the bioaerosols. Both microbial counts and diversity increased as the aeration rate increased. Brevundimonas (63.82%), Chryseobacterium (16.54%), and Micrococcaceae (12.37%) were the dominant intestinal bacteria at an aeration rate of 0.3 m3/h. Pseudochrobactrum (33.10%), Citrobacter (21.28%), and Yersinia (18.21%) were the dominant intestinal bacteria at an aeration rate of 1.2 m3/h. The level, particle size distribution, population structure, and diversity of the bioaerosols were all affected by aeration rate. The source tracker results indicated that water and the surrounding air were the two main bioaerosol sources. The contribution of water is greater at larger levels of aeration. Inhalation was the main pathway of microbial aerosol intake for people in the surrounding area. The exposure hazard quotients for adult males were generally higher than those for adult females. Necessary measures should be taken to ensure worker safety.

Effects of return sludge alkaline treatment on sludge reduction in laboratory-scale anaerobic-anoxic-oxic process.

Three alkaline treatments (pH 10, 11, and 12 for 1 h) were used to treat return sludge alone to reduce sludge production in laboratory-scale anaerobic-anoxic-oxic processes. After 99 days of operation, alkaline treatments at pH 10 and 11 led to accumulative excess sludge production and sludge yield reduction of 18.8%-31.7% and 14.7%-27.8%, respectively. However, alkaline treatment at pH 12 led to system breakdown because of sludge bulking. The alkaline treatment at pH 10 did not affect the chemical oxygen demand and NH4+-N removals of the system and sludge volume index (SVI) of aerobic activated sludge. However, alkaline treatments at pH 11 and 12 obviously deteriorated the wastewater treatment efficiencies and sludge SVI. Although the three treatments increased the effluent pH by 0.08 to 0.38, the effluent pH of three systems were all lower than 9.00. The treatments at pH 10 and 11 increased the specific oxygen uptake rate of activated sludge, whereas the treatment at pH 12 decreased this rate.

State of the art on granular sludge by using bibliometric analysis.

With rapid industrialization and urbanization in the nineteenth century, the activated sludge process (ASP) has experienced significant steps forward in the face of greater awareness of and sensitivity toward water-related environmental problems. Compared with conventional flocculent ASP, the major advantages of granular sludge are characterized by space saving and resource recovery, where the methane and hydrogen recovery in anaerobic granular and 50% more space saving, 30-50% of energy consumption reduction, 75% of footprint cutting, and even alginate recovery in aerobic granular. Numerous engineers and scientists have made great efforts to explore the superiority over the last 40 years. Therefore, a bibliometric analysis was desired to trace the global trends of granular sludge research from 1992 to 2016 indexed in the SCI-EXPANDED. Articles were published in 276 journals across 44 subject categories spanning 1420 institutes across 68 countries. Bioresource Technology (293, 11.9%), Water Research (235, 9.6%), and Applied Microbiology and Biotechnology (127, 5.2%) dominated in top three journals. The Engineering (991, 40.3%), China (906, 36.9%), and Harbin Inst Technol, China (114, 4.6%) were the most productive subject category, country, and institution, respectively. The hotspot is the emerging techniques depended on granular reactors in response to the desired removal requirements and bio-energy production (primarily in anaerobic granular sludge). In view of advanced and novel bio-analytical methods, the characteristics, functions, and mechanisms for microbial granular were further revealed in improving and innovating the granulation techniques. Therefore, a promising technique armed with strengthened treatment efficiency and efficient resource and bio-energy recovery can be achieved.

Investigation on mechanism of phosphate removal on carbonized sludge adsorbent.

For the removal of phosphate (PO43-) from water, an adsorbent was prepared via carbonization of sewage sludge from a wastewater treatment plant: carbonized sludge adsorbent (CSA). The mechanism of phosphate removal was determined after studying the structure and chemical properties of the CSA and its influence on phosphate removal. The results demonstrate that phosphate adsorption by the CSA can be fitted with the pseudo second-order kinetics and Langmuir isotherm models, indicating that the adsorption is single molecular layer adsorption dominated by chemical reaction. The active sites binding phosphate on the surface are composed of mineral particles containing Si/Ca/Al/Fe. The mineral containing Ca, calcite, is the main factor responsible for phosphate removal. The phosphate removal mechanism is a complex process including crystallization via the interaction between Ca2+ and PO43-; formation of precipitates of Ca2+, Al3+, and PO43-; and adsorption of PO43- on some recalcitrant oxides composed of Si/Al/Fe.