De Novo Assembly, Characterization, and Comparative Transcriptome Analysis of Mature Male and Female Gonads of Rabbitfish (Siganus oramin) (Bloch & Schneider, 1801).

The rabbitfish, Siganus oramin, is a commercially important table fish in southeastern China. However, there have been few studies on its gonad development and reproduction regulation. Comparative transcriptome analysis was first performed on adult male and female gonads of S. oramin. In total, 47,070 unigenes were successfully assembled and 22,737 unigenes were successfully annotated. Through comparative transcriptome analysis of male and female gonads, a total of 6722 differentially expressed genes were successfully identified, with 3528 upregulated genes and 3154 downregulated genes in the testes. In addition, 39 differentially expressed reproduction-related genes were identified. Finally, quantitative real-time PCR was used to validate the expression levels of several differentially expressed genes. These results provide important data for further studying the function of reproduction-related genes and the molecular mechanism regulating gonad development and reproduction in S. oramin.

Graph neural networks for preference social recommendation.

Social recommendation aims to improve the performance of recommendation systems with additional social network information. In the state of art, there are two major problems in applying graph neural networks (GNNs) to social recommendation: (i) Social network is connected through social relationships, not item preferences, i.e., there may be connected users with completely different preferences, and (ii) the user representation of current graph neural network layer of social network and user-item interaction network is the output of the mixed user representation of the previous layer, which causes information redundancy. To address the above problems, we propose graph neural networks for preference social recommendation. First, a friend influence indicator is proposed to transform social networks into a new view for describing the similarity of friend preferences. We name the new view the Social Preference Network. Next, we use different GNNs to capture the respective information of the social preference network and the user-item interaction network, which effectively avoids information redundancy. Finally, we use two losses to penalize the unobserved user-item interaction and the unit space vector angle, respectively, to preserve the original connection relationship and widen the distance between positive and negative samples. Experiment results show that the proposed PSR is effective and lightweight for recommendation tasks, especially in dealing with cold-start problems.

Source apportionment of nitrate in the Pearl River Estuary using δ15N and δ18O values and isotope mixing model.

The mitigation of eutrophication in the Pearl River Estuary (PRE) has encountered numerous challenges in regards to source control. Herein, the isotope mixing model (SIAR) was used to quantify the primary nitrate sources in the PRE. The results showed that the nitrate levels were significantly higher in the high-flow season than in the low-flow season. Meanwhile, we found the most important nitrate sources were manure and sewage during the high-flow season, with a contribution ratio of 47 % in the low salt area (LSA) and 29 % in the high salt area (HSA). During the low-flow season, the primary nitrate sources were identified as reduced nitrogen fertilizer in the LSA and manure and sewage in the HSA, which accounted for 52 % and 44 %, respectively. Furthermore, we also suggest that a feasible measure might be to control the pollution caused in the PRE by manure and sewage as well as reduced nitrogen fertilizer.

Mechanism and characterization of microplastic aging process: A review.

With the increasing production of petroleum-based plastics, the problem of environmental pollution caused by plastics has aroused widespread concern. Microplastics, which are formed by the fragmentation of macro plastics, are bio-accumulate easily due to their small size and slow degradation under natural conditions. The aging of plastics is an inevitable process for their degradation and enhancement of adsorption performance toward pollutants due to a series of changes in their physiochemical properties, which significantly increase the toxicity and harm of plastics. Therefore, studies should focus on the aging process of microplastics through reasonable characterization methods to promote the aging process and prevent white pollution. This review summarizes the latest progress in natural aging process and characterization methods to determine the natural aging mechanism of microplastics. In addition, recent advances in the artificial aging of microplastic pollutants are reviewed. The degradation status and by-products of biodegradable plastics in the natural environment and whether they can truly solve the plastic pollution problem have been discussed. Findings from the literature pointed out that the aging process of microplastics lacks professional and exclusive characterization methods, which include qualitative and quantitative analyses. To lessen the toxicity of microplastics in the environment, future research directions have been suggested based on existing problems in the current research. This review could provide a systematic reference for in-depth exploration of the aging mechanism and behavior of microplastics in natural and artificial systems.

An overview of the direct and indirect effects of acid rain on plants: Relationships among acid rain, soil, microorganisms, and plants.

Acid rain (AR) causes numerous environmental problems and complex negative effects on plants globally. Many studies have previously reported on direct effects of AR or its depositional substances on plant injury and performance. However, few studies have addressed the indirect effects of AR on plants as mediated by soil microorganisms and the abiotic environment of the soil rhizosphere. The indirect effects (e.g., AR â†’ soil microorganisms→plants) need greater attention, because acidic deposition not only affects the distribution, composition, abundance, function, and activity of plant-associated microorganisms, but also influences the dynamics of some substances in the soil in a way that may be harmful to plants. Therefore, this review not only focused on the direct effects of AR on plant performance, growth, and biomass allocations from a whole-plant perspective, but also addressed the pathway of AR-soil chemical characteristics-plants, which explains how soil solute leaching and acidification by AR will reduce the availability of essential nutrients and increase the availability of heavy metals for plants, affecting carbon and nitrogen cycles. Mainly, we evaluated the AR-soil microorganisms-plants pathway by: 1) synthesizing the potential roles of soil microbes in alleviating soil acidic stress on plants and the adverse effects of AR on plant-associated soil microorganisms; 2) exploring how plant mycorrhizal types affect the detection of AR effect on plants. The meta-analysis showed that the effects of AR-induced pH on leaf chlorophyll content, plant height, and plant root biomass were dependent on plant mycorrhizal types. Some possible reasons for different synergy between mycorrhizal symbiotic types and plants were discussed. Future research relating to the effects of AR on plants should focus on the combined direct and indirect effects to evaluate how AR affects plant performance comprehensively.

Prenatal Sevoflurane Exposure Impairs the Learning and Memory of Rat Offspring via HMGB1-Induced NLRP3/ASC Inflammasome Activation.

The neurotoxic effects of sevoflurane anesthesia on the immature nervous system have aroused public concern, but the specific effects and mechanism remain poorly understood. Pyroptosis caused by the activation of the NLRP3 inflammasome is pivotal for cell survival and acts as a key player in cognitive impairment. This study was carried out to determine the critical role of the NLRP3 inflammasome and high-mobility group box 1 (HMGB1) in sevoflurane-induced cognitive impairment. On gestational day 20 (G20), 3% sevoflurane was administered for 4 h to pregnant rats. The hippocampus and cerebral cortex of the offspring were harvested at postnatal day 1 (P1) for Western blotting and immunofluorescence staining. Pregnant rat sevoflurane exposure increased the protein levels of NLRP3, ASC, cleaved-caspase 1 (p20), mature-IL-1ß (m-IL-1ß), and HMGB1 in the cerebral cortex and hippocampus of offspring rats. More microglial cells of offspring were also observed after sevoflurane anesthesia. The Morris water maze (MWM) test was implemented to evaluate cognitive function from postnatal day 30 (P30) to postnatal 35 (P35) of offspring. The sevoflurane-treated offspring took longer than the control rats to find the MWM platform during the learning phase. Furthermore, they had a longer travel distance and less time in the target quadrant than the control rats in the probe trial. Maternal intraperitoneal injection of glycyrrhizin (an inhibitor of HMGB1) attenuated the sevoflurane-induced microglia and NLRP3/ASC inflammasome activation and cognitive impairment of offspring. Simultaneously, the sevoflurane-induced increase in Toll-like receptors (TLR4) and nuclear factor-κB (NF-κB) was significantly reduced by glycyrrhizin. We concluded that the HMGB1 inhibitor may repress the sevoflurane-induced activation of the NLRP3/ASC inflammasome and cognitive dysfunction and that TLR4/NF-κB signaling maybe the key pathway, at least in part.

Efficient photocatalytic remediation of typical antibiotics in water via Mn3O4 decorated carbon nitride nanotube.

Antibiotic abuse will seriously affect the ecology and environment. Photocatalytic oxidation technology based on carbon nitride (g-C3N4) has been widely adopted to treat wastewater containing antibiotics. Here, a novel composite photocatalyst MCNT was prepared by loading manganese oxide (Mn3O4) on the surface of g-C3N4 nanotubes (CNT). Three typical antibiotics, trimethoprim (TMP), norfloxacin (NOR), and tetracycline (TC) were used as model contaminants to evaluate the oxidative properties of prepared materials. Compared with bulk g-C3N4, the degradation rates of TMP, NOR, and TC catalyzed by MCNT-5 were increased by 2, 3, and 1.4 times, respectively, mainly due to 1) the larger specific surface area of the nanotube structure of CNT, which provides abundant active sites for antibiotic adsorption and catalytic oxidation, and 2) the loading of Mn3O4, which promotes the directional migration of photogenerated charges and improves the separation efficiency of photogenerated electrons and holes. The free radical capture and quenching experiments confirmed that MCNT degraded the target organic pollutants with hydroxyl radical (·OH) and singlet oxygen (1O2) as the main active oxidants. This catalyst maintained 80% photocatalytic oxidation performance after five cyclic experiments. This study provides new insights into developing efficient, stable, and environmentally-friendly photocatalysts and provides a new dimension to mitigate the antibiotic pollution problem.

Characterization of pathogenic synovial IL-17A-producing CD8+ T cell subsets in collagen-induced arthritis.

Using a murine collagen-induced arthritis model, we characterized the heterogeneity of synovial CD8+ T cells based on the expression of chemokine receptors, cytokines, and nuclear transcription factors. Four subsets, i.e. CXCR3-CCR4- cells, CXCR3+CCR4- cells, CXCR3+CCR4+ cells, and CXCR3-CCR4+ cells, were present in synovial CD8+CD62L-CCR6+IL-23R+CCR10- T cells. CXCR3-CCR4- cells belonged to exhausted CD8+ T cells. CXCR3+CCR4- cells were Tc17.1 cells expressing both IL-17A and IFN-γ. CXCR3+CCR4+ cells were transitional Tc17.1 cells expressing IL-17A but lower IFN-γ, and CXCR3-CCR4+ cells were Tc17 cells expressing IL-17A but no IFN-γ. Transitional Tc17.1 cells can differentiate into Tc17.1 cells in vitro under the instruction of IL-12. Tc17.1 cells and transitional Tc17.1 cells strongly induced the expression of pro-inflammatory mediators in synovial fibroblasts, whereas Tc17 cells were less potent in doing so. IFN-γ was involved in the higher pathogenicity of Tc17.1 cells and transitional Tc17.1 cells on synovial fibroblasts. This study expands the understanding of Tc17 biology by unveiling the phenotypic and functional heterogeneity of synovial IL-17A-expressing CD8+ T cells. These heterogeneous IL-17A-expressing CD8+ T cells could be novel therapeutic targets in future arthritis treatment.

Personal protective equipment (PPE) disposal during COVID-19: An emerging source of microplastic and microfiber pollution in the environment.

Waste generated by healthcare facilities during the COVID-19 pandemic has become a new source of pollution, particularly with the widespread use of single-use personal protective equipment (PPE). Releasing microplastics (MPs) and microfibers (MFs) from discarded PPE becomes an emerging threat to environmental sustainability. MPs/MFs have recently been reported in a variety of aquatic and terrestrial ecosystems, including water, deep-sea sediments, air, and soil. As COVID-19 spreads, the use of plastic-made PPE in healthcare facilities has increased significantly worldwide, resulting in massive amounts of plastic waste entering the terrestrial and marine environments. High loads of MPs/MFs emitted into the environment due to excessive PPE consumption are easily consumed by aquatic organisms, disrupting the food chain, and potentially causing chronic health problems in humans. Thus, proper management of PPE waste is critical for ensuring a post-COVID sustainable environment, which has recently attracted the attention of the scientific community. The current study aims to review the global consumption and sustainable management of discarded PPE in the context of COVID-19. The severe impacts of PPE-emitted MPs/MFs on human health and other environmental segments are briefly addressed. Despite extensive research progress in the area, many questions about MP/MF contamination in the context of COVID-19 remain unanswered. Therefore, in response to the post-COVID environmental remediation concerns, future research directions and recommendations are highlighted considering the current MP/MF research progress from COVID-related PPE waste.

IL-18BP Alleviates Anxiety-Like Behavior Induced by Traumatic Stress via Inhibition of the IL-18R-NLRP3 Signaling Pathway in a Mouse Model of Hemorrhagic Shock and Resuscitation.

Psychological distress and posttraumatic stress, including anxiety, severely influence life quality. Previously, we reported that interleukin-18 (IL-18) was involved in pyroptosis-induced emotional changes in a rodent model of hemorrhagic shock and resuscitation (HSR). Here, we aimed to continue our investigation on the role of IL-18 binding protein (IL-18BP), which exhibits excellent anti-inflammatory effects as an IL-18 negative regulator. Mice were administered with an intraperitoneal injection of IL-18BP after HSR exposure and anxiety-like behavior was examined using the open-field test and elevated plus maze test. Moreover, the following variables post-HSR were measured: (1) the activation of astrocytes; (2) pyroptosis-associated factors including cleaved caspase-1, GSDMD, IL-18; (3) the roles of IL-18 receptor (IL-18R)-NOD-like receptor pyrin domain-containing-3 (NLRP3) signal with the application of the NLRP3 specific agonist or astrocyte-specific NLRP3 knockout mice. IL-18BP administration remarkably alleviated HSR-induced anxiety-like behavior, astrocytic activation, and increases in pyroptosis-associated factors, while NLRP3 agonist nigericin partially reversed IL-18BP-induced neuroprotective effects. Astrocyte-specific NLRP3 knockout mice exhibited relatively less anxiety-like behavior. Similarly, IL-18BP exhibited an anti-pyroptosis effect in astrocytes in an in vitro model of low oxygen-glucose deprivation. These findings offer unique perspectives on HSR-induced posttraumatic stress and indicate that inhibition of IL-18R-NLRP3 signal via IL-18BP can attenuate astrocytic activation and pyroptosis, broadening the therapeutic landscape for patients with psychological distress and posttraumatic stress.

Enhanced activation of PMS by a novel Fenton-like composite Fe3O4/S-WO3 for rapid chloroxylenol degradation.

Chloroxylenol (PCMX) is widely used as disinfectant since the epidemic outbreak due to its effective killing of Covid-19 virus. Its stable chemical properties make it frequently detected in surface water. Herein, we successfully modified Fe3O4 nanoparticles with S-WO3 (X-Fe3O4/S-WO3) to accelerate the Fe2+/Fe3+ cycle. The composite has outstanding PCMX degradation and peroxymonosulfate (PMS) decomposition efficiency over a wide pH range (3.0 âˆ¼ 9.0). 80-Fe3O4/S-WO3/PMS system not only increased PMS decomposition efficiency from 27.7% to 100.0%, but also realized an enhancement of PCMX degradation efficiency by 16 times in comparison with that of Fe3O4 alone. The catalyst utilization efficiency reached 0.3506 mmol∙g-1∙min-1 which stands out among most Fenton-like catalysts. The composite has excellent degradation ability to a variety of emerging pollutants, such as antibiotics, drugs, phenols and endocrine disrupters, and at least a 90% removal efficiency reached in 10 min. The degradation of PCMX was dominated by HO•, SO4 •- and 1O2. The degradation pathways of PCMX were analyzed in detail. The component WS2 in S-WO3 plays a co-catalytic role instead of WO3. And the exposed active W4+ surf. efficiently enhanced the Fe3+/Fe2+ cycle, thereby complete PMS decomposition and high catalytic efficiency were achieved. Our findings clarify that applying two-dimensional transition metal sulfide WS2 to modify heterogeneous Fe3O4 is a feasible strategy to improve Fenton-like reaction and provide a promising catalyst for PCMX degradation.

Isotherm models for adsorption of heavy metals from water - A review.

Adsorption is a widely used technology for removing and separating heavy metal from water, attributed to its eco-friendly, cost-effective, and high efficiency. Adsorption isotherm modeling has been used for many years to predict the adsorption equilibrium mechanism, adsorption capacity, and the inherent characteristics of the adsorption process, all of which are substantial in evaluating the performance of adsorbents. This review summarizes the development history, fundamental characteristics, and mathematical derivations of various isotherm models, along with their applicable conditions and application scenarios in heavy metal adsorption. The latest progress in applying isotherm models with a one-parameter, two-parameter, and three-parameter in heavy metal adsorption using carbon-based materials, which has gained much attention in recent years as low-cost adsorbents, is critically reviewed and discussed. Several experimental factors affecting the adsorption equilibrium, such as solution pH, temperature, ionic strength, adsorbent dose, and initial heavy metal concentration, are briefly discussed. The criteria for selecting the optimum isotherm for heavy metal adsorption are proposed by comparing various adsorption models and analyzing mathematical error functions. Finally, the relative performance of different isotherm models for heavy metal adsorption is compared, and the future research gaps are identified.

Efficient Oxidation of Paracetamol Triggered by Molecular-Oxygen Activation at ß-Cyclodextrin-Modified Titanate Nanotubes.

Titanate nanotubes (TNTs) were coated with a cyclic oligosaccharide (carboxymethyl-ß-cyclodextrin, CM-ß-CD) to obtain a photocatalyst (CM-ß-CD-TNT) for efficiently activating molecular oxygen and removing the target contaminant. The hydrophobic cavity and the large specific surface area of the photocatalyst provide abundant active sites for activating molecular oxygen. The free radical capture experiment and quenching experiment showed that cyclodextrin could facilitate adsorption and activation of molecular oxygen to produce O2 .- . Therefore, compared with the pristine TNT, CM-ß-CD-TNT accelerated the oxidation efficiency of paracetamol (APAP) by 3.4 times. Moreover, the ring cleavage reaction induced by CM-ß-CD-TNT effectively reduced the acute toxicity of wastewater containing APAP. Furthermore, 100% of bisphenol A (BPA), bisphenol S (BPS), phenol, 2,4-dichlorophen (2,4-DCP), and carbamazepine (CBZ) were degraded by CM-ß-CD-TNT after 2.5 h ultraviolet (UV) light irradiation. This strategy provides a new dimension for the advanced treatment of organic wastewater by organic macrocyclic molecule-modified materials.

A novel cationic graphene modified cyclodextrin adsorbent with enhanced removal performance of organic micropollutants and high antibacterial activity.

The coexistence of pathogenic microorganisms and refractory organic chemicals in water nurtures certain biological and chemical risks to human beings and the water environment as a whole. For an environmentally friendly utilization of water cleaning and recycling technologies, a bifunctional cationic cyclodextrin material (GD-DTAC) with adsorption and bactericidal function was designed. By a simple crosslinking method, GD-DTAC was prepared with graphene supported citric acid-ß-cyclodextrin polymer (GD) and dimethyldodecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DTAC). Following the introduction of rich quaternary ammonium groups by DTAC, GD-DTAC realized a double regulation of surface positive charge and wettability. The maximum adsorption capacities of Roxarsone (ROX), Methyl Orange (MO) and Bisphenol A (BPA) were 153.59 mg/g, 445.60 mg/g and 237.90 mg/g, respectively. Antibacterial activity tests showed the efficiency of DTAC not only for enhanced adhesion resistance, but it also realized the sterilization function. This work displays the potential of the prepared bifunctional materials for the removal of pollutants from wastewater as well as the suppression of micro-pollutants. The successful preparation of GD-DTAC provided a basis for the bifunctional material, which showed a great potential in adsorption and antibiosis.

In-situ production and activation of H2O2 for enhanced degradation of roxarsone by FeS2 decorated resorcinol-formaldehyde resins.

Fenton technology performs well in high-risk roxarsone (ROX) removal, but it is limited by the high H2O2 transportation and storage risks. Herein, FeS2 decorated resorcinol-formaldehyde resins (FeS2-RFR) were successfully prepared to in-situ produce and utilize H2O2 for efficient removal of ROX. Under solar light illumination, resorcinol-formaldehyde resins (RFR) efficiently generated a high concentration of H2O2, with a yield of 500 µmol g-1 h-1. FeS2 can in-situ decompose H2O2 to generate ·OH, participating in the oxidation of ROX. As a result, the FeS2-RFR catalyst degraded more than 97% of ROX within 2 h and ROX was selectively degraded into low-toxic As(V), which can be simply removed by traditional adsorption or precipitation processes. During the degradation of ROX, ·OH played a dominant role. Moreover, the cations (Na+, K+, and Ca2+), anions (SO42-, Cl-), and humic acid had no noticeable inhibition effect on ROX removal. Furthermore, FeS2-RFR can still remove 70% of ROX even after three cycles, proving that this in-situ photo-Fenton system exhibited stability. This study innovatively proposed a double-active site FeS2-RFR photocatalyst for in-situ production and activation of H2O2 and showed a sustainable and eco-friendly way for organoarsenic compounds degradation.

Risk assessment of antibiotic resistance genes in the drinking water system.

Antibiotic resistance genes (ARGs) are extensively detected in various environmental media, whose risk assessment in the drinking water systems has not been comprehensive. This study established a new risk assessment of ARGs in the drinking water systems, considering the chlorine-resistance ability, transferability, and ARGs harboring potential of pathogens. The risk of ARGs in a typical drinking water reservoir was also evaluated based on the detection of ARGs and antibiotic-resistant bacteria (ARB). Fourteen ARGs were detected with a relative concentration range of 10-4-10-3 (ARGs/16S rRNA gene). Five isolated ARB were identified as human opportunistic pathogens, one of which (Pseudomonas aeruginosa HLS-6, CCTCC AB 2017269) is resistant to hundreds of milligrams per liter levels of antibiotics and low-level chlorine. This result indicated that ARB tolerant to high-levels of antibiotics could be isolated from environments containing trace levels of antibiotics. Moreover, complete genome sequencing confirmed the inclusion of ARGs (sul1, aadA2) on the class I integron in HLS-6, indicating that the risk of ARGs in this drinking water reservoir could be classified as resistance risk ranking in drinking water system 1 (R3DW 1). The risk assessment of ARGs in this study provides a clear understanding of ARG risk in drinking water systems. The results reveal that the ARGs and ARB contamination of drinking water reservoirs pose significant challenges for drinking water treatment efficiency and affect drinking water safety.

Pericytes for Therapeutic Approaches to Ischemic Stroke.

Pericytes are perivascular multipotent cells located on capillaries. Although pericytes are discovered in the nineteenth century, recent studies have found that pericytes play an important role in maintaining the blood-brain barrier (BBB) and regulating the neurovascular system. In the neurovascular unit, pericytes perform their functions by coordinating the crosstalk between endothelial, glial, and neuronal cells. Dysfunction of pericytes can lead to a variety of diseases, including stroke and other neurological disorders. Recent studies have suggested that pericytes can serve as a therapeutic target in ischemic stroke. In this review, we first summarize the biology and functions of pericytes in the central nervous system. Then, we focus on the role of dysfunctional pericytes in the pathogenesis of ischemic stroke. Finally, we discuss new therapies for ischemic stroke based on targeting pericytes.

Removal of organic pollutants from aqueous solution using metal organic frameworks (MOFs)-based adsorbents: A review.

The development of metal organic frameworks (MOFs) has recently drawn a lot of scientific interest in water treatment due to the unique properties such as tunable porosities, large pore volumes, hierarchical structures, excellent adsorption and regeneration performances. MOFs represent an eco-friendly alternative to conventional adsorbents especially for the adsorptive removal of noxious organic pollutants from aqueous solution. Advanced MOFs' performances are justified by the introduction of functional groups, magnetic moieties, and specific foreign materials onto MOFs. This however leads to increase in the manufacturing costs of MOFs and consequently possess a huge challenge in large-scale applications. This review hence critically discusses the recent progresses in the development of MOFs-based adsorbents for the removal of selected organic pollutants (e.g., dyes, antibiotics and pesticides) from aqueous solution. Furthermore, major interaction mechanisms between MOFs and organic pollutants in response to numerous experimental conditions, such as pH, temperature, coexisting ions are put forward. Finally, some recommendations in support for designing MOFs with improved adsorption performances are also highlighted.

Lead immobilization in soil using new hydroxyapatite-like compounds derived from oyster shell and its uptake by plant.

Protecting the natural environment and ecological systems from the inorganic pollutants such as lead (Pb) has highlighted the urgent need to develop new and effective approaches for this substance's immobilization in soil. In this study, new, low-cost, and eco-friendly hydroxyapatite (HAp)-like compounds were prepared by reacting oyster shell (Oys) with diammonium phosphate ((NH4)2HPO4) (DAP) and calcium hydroxide (Ca(OH)2) at 25-28 °C (OyOHr) and 100 °C (OyOHh). Furthermore, OyOHr and OyOHh were assessed for their effectiveness to immobilize Pb in soil and suppress Pb uptake by Indian spinach (Basella Alba L.). Application of 0.5% OyOHr and OyOHh to soil (by weight) reduced Pb concentration in the shoots by 76.9-78.0% compared to control (CK), to a level that was slightly higher (by 15.5-21.5%) than the recommended food safety level (2 mg kg-1) suggested by WHO. The changes in Pb fractions revealed that the total contents of oxidizable and residual forms in OyOHr or OyOHh after harvest was >415.0 mg kg-1, which indicated that >92% of Pb when added to the soil, was immobilized and not able to be taken up by plants. The proposed Pb immobilization mechanism might be the dissolution of OyOHr or OyOHh followed by hydroxypyromorphite (Pb10(PO4)6(OH)2) (HP) formation. Due to their facile preparation and eco-friendly and excellent Pb immobilizing characteristics, OyOHr or OyOHh could be readily integrated into current farming systems to mitigate the risk of Pb transferring to plants. However, OyOHr seemed a better immobilizing agent correspond to OyOHh in terms of cost and efficiency.

Metal-organic frameworks derived C/TiO2 for visible light photocatalysis: Simple synthesis and contribution of carbon species.

A series of in-situ carbon-doped TiO2 (Cx/TiO2) composites with a porous and crystalline structure were successfully synthesized via one-step and low-temperature calcination of titanium metal-organic framework (MOF), MIL-125(Ti). The resultant materials were comprehensively investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), N2 adsorption-desorption measurements, UV-vis diffuse reflectance spectrum (DRS), photoluminescence (PL) spectra and photoelectrochemical measurements, and their photocatalytic activities for bisphenol A (BPA) degradation were assessed. Compared with the benchmark TiO2 photocatalyst (P25), the Cx/TiO2 composite material with high specific surface, lower band gap, and reduced photogenerated electron hole ratio exhibited outstanding photodegradation activity and durability for BPA, which could be attributed to the combined effect of co-doping of multiple carbon species (substituent carbon and carbonate) and porous structure. During BPA degradation, the holes and superoxide radicals were the primary role oxidative species in the reaction process. Therefore, this new efficient photocatalyst is promising candidate for photodegradation of organic pollutants.