Enhancement Effect Induced by the Second Metal to Promote Ozone Catalytic Oxidation of VOCs.

It is a promising research direction to develop catalysts with high stability and ozone utilization for low-temperature ozone catalytic oxidation of VOCs. While bimetallic catalysts exhibit excellent catalytic activity compared with conventional single noble metal catalysts, limited success has been achieved in the influence of the bimetallic effect on the stability and ozone utilization of metal catalysts. Herein, it is necessary to systematically study the enhancement effect in the ozone catalytic reaction induced by the second metal. With a simple continuous impregnation method, a platinum-cerium bimetallic catalyst is prepared. Also highlighted are studies from several aspects of the contribution of the second metal (Ce) to the stability and ozone utilization of the catalysts, including the "electronic effect" and "geometric effect". The synergistic removal rate of toluene and ozone is nearly 100% at 30 °C, and it still shows positive stability after high humidity and a long reaction time. More importantly, the instructive significance, which is the in-depth knowledge of enhanced catalytic mechanism of bimetallic catalysts resulting from a second metal, is provided by this work.

The photocatalytic reduction of U(VI) by Ag-doped SnS2 materials under visible light.

Efficient degradation of uranium(VI) (U(VI)) in wastewater is an urgent problem because of the chemical toxicity and radiotoxicity. In this study, the Agx-SnS2 photocatalysts were compounded by a simple hydrothermal method, effectively removing U(VI) under visible light in water. Compared with SnS2, the results indicated that Agx-SnS2 would decrease the crystallinity without destroying the crystal structure. Moreover, it has excellent photocatalytic performance on the degradation rate of U(VI). Ag0.5-SnS2 exhibited a prominent photocatalytic reduction efficiency of UO22+ of about 86.4% under optical light for 75 min. This was attributed to Ag-doped catalysts, which can narrow the band gap and enhance absorption in visible light. Meanwhile, the doping of Ag promoted the separation of photoinduced carriers, so that more photogenerated charges participated in the photocatalytic reaction. The stability and reusability were verified by the cycle test and the potential photocatalytic mechanism was analyzed based on the experiment.

Insights into the fate of antibiotics in constructed wetland systems: Removal performance and mechanisms.

Antibiotics have been recognized as emerging contaminants that are widely distributed and accumulated in aquatic environment, posing a risk to ecosystem at trace level. Constructed wetlands (CWs) have been regarded as a sustainable and cost-effective alternative for efficient elimination of antibiotics. This review summarizes the removal of 5 categories of widely used antibiotics in CWs, and discusses the roles of the key components in CW system, i.e., substrate, macrophytes, and microorganisms, in removing antibiotics. Overall, the vertical subsurface flow CWs have proven to perform better in terms of antibiotic removal (>78%) compared to other single CWs. The adsorption behavior of antibiotics in wetland substrates is determined by the physicochemical properties of antibiotics, substrate configuration and operating parameters. The effects of wetland plants on antibiotic removal mainly include direct (e.g., plant uptake and degradation) and indirect (e.g., rhizosphere processes) manners. The possible interactions between microorganisms and antibiotics include biosorption, bioaccumulation and biodegradation. The potential strategies for further enhancement of the antibiotic removal performance in CWs included optimizing operation parameters, innovating substrate, strengthening microbial activity, and integrating with other treatment technologies. Taken together, this review provides useful information for facilitating the development of feasible, innovative and intensive antibiotic removal technologies in CWs, as well as enhancing the economic viability and ecological sustainability.

Environmental, energy, and economic impact assessment of sludge management alternatives based on incineration.

In this study, different management strategies for sewage sludge disposal were evaluated associated with environmental, energy, and economic impact, using life cycle assessment (LCA), cumulative energy demand (CED) and life cycle costing (LCC) approaches. Four scenarios, including mono-incineration, co-incineration in municipal solid wastes (MSW) incineration plant, co-incineration in coal-fired power plant and co-incineration in cement kiln, were assessed. The environmental burdens generated from the sludge incineration contributed primarily to the global warming, followed by eutrophication, marine aquatic ecotoxicity, and human toxicity potential across the four scenarios. Furthermore, mono-incineration scenario appeared to be the most environmentally unfriendly, energy and economy intensive alternative, with the LCA, CED and LCC value of 5.41E-09, 1736 MJ and 1.84 million CNY, respectively. By contrast, co-incineration in cement kiln exhibited the lowest CED (368 MJ), LCC (0.59 million CNY), and environmental burdens (1.02E-09). In addition, the sensitivity analysis indicated that four scenarios were sensitive to the changes in the electricity efficiency and the moisture content contained in sewage sludge, suggesting that it was of great significance to enhance the efficiency of sludge dewatering and thermal drying The findings of this study can provide scientific reference for selecting the optimal strategies for the most environmentally and economically friendly sewage sludge management with optimum energy efficiency.

Fate and mechanistic insights into nanoscale zerovalent iron (nZVI) activation of sludge derived biochar reacted with Cr(VI).

While nanoscale zero-valent iron modified biochar (nZVI-BC) have been widely investigated for the removal of heavy metals, the corrosion products of nZVI and their interaction with heavy metals have not been revealed yet. In this paper, nZVI-BC was synthesized and applied for the removal of Cr(VI). Batch experiments indicated that the adsorption of Cr(VI) fit Langmuir isotherm, with the maximum removal capacity at 172.4 mg/g at pH 2.0. SEM-EDS, BET, XRD, FT-IR, Raman and XPS investigation suggested that reduction of Cr(VI) to Cr(III) was the major removal mechanism. pH played an important role on the corrosion of nZVI-BC, at pH 4.5 and 2.0, FeOOH and Fe3O4 were detected as the major iron oxide, respectively. Therefore, FeOOH-BC and Fe3O4-BC were further prepared and their interaction with Cr were studied. Combining with DFT calculations, it revealed that Fe3O4 has higher adsorption capacity and was responsible for the effective removal of Cr(VI) through electrostatic attraction and reduction under acidic conditions. However, Fe3O4 will continue to convert to the more stable FeOOH, which is the key to for the subsequent stabilization of the reduced Cr(III). The results showed that the oxide corrosion products of nZVI-BC were subjected to the environment, which will eventually affect the fate and transport of the adsorbed heavy metal.

The algicidal efficacy and the mechanism of Enterobacter sp. EA-1 on Oscillatoria dominating in aquaculture system.

The global escalation and intensification of cyanobacterial blooms require powerful algaecides. This study investigated the algicidal efficacy and mechanism of EA-1 against Oscillatoria. Bacteria EA-1, identified as Enterobacter, was isolated with high algicidal activity against harmful cyanobacteria. Results showed that a complete removal of Oscillatoria was observed within 3 days with the initial Chl-a concentration of 1.74 mg/L. Physiological responses of Oscillatoria revealed that EA-1 induced severe lipid peroxidation and the ultimate decline of antioxidant enzyme activities. Moreover, the contents for both intracellular protein and carbohydrate of each algae cell increased first and then decreased. Scanning electron microscope (SEM) and transmission electron microscopy (TEM) analysis clarified that the possible process of Oscillatoria lysis included the breach of cross wall, followed by the disruption of photosynthetic membrane and incipient nucleus, and the ultimate outflow of inclusion. Confocal laser scanning microscopy (CLSM) analysis illustrated the degradation process of incipient nucleus in Oscillatoria.

The efficient biomineralization and adsorption of cadmium (Cd2+) using secretory organo-biominerals (SOBs) produced by screened Alcaligenes faecalis K2.

Cadmium-contaminated wastewater has attracted increasing concerns due to its non-biodegradable properties and high toxicity. To explore eco-friendly and economically feasible strategies, the screened Alcaligenes faecalis K2 were employed for the biomineralization and recovery of Cd2+ from wastewater while producing considerable secretory organo-biominerals (SOBs) as bioadsorbents. At 75 mg/L Cd2+ exposure, 85.5% of Cd2+ was removed by K2, 43.0% of which was fixed in the granular SOBs. SOBs were convenient for separating from the solution. The adsorption capacity of granular sorbent made from SOBs was verified to be greater than 77.1 mg/g. Practically, 89.5% of 75 mg/L of Cd2+ could be stably removed while ereK2 continuously generated SOBs in a moving-bed biofilm reactor (MBBR). To sum up, the production of bioadsorbents can be achieved by K2, while removing Cd with live microorganisms, which was conducive to making full use of materials and improving Cd removal efficiency.

The behaviors of Microcystis aeruginosa and microcystins during the Fe2+/persulfate (PS) preoxidation-coagulation and flocs storage period.

The frequent occurrence of toxin-producing cyanobacteria blooms driven by anthropogenic eutrophication has become a major threat to aquaculture ecosystems worldwide. In this study, the behavior of M. aeruginosa cells during flocs storage period of 6 days was first investigated after pre-oxidation and coagulation of Fe2+/PS. Fe2+/PS achieved a superior removal efficiency of 90.7% for OD680 and 90.4% for chl-a. The contents of extracellular MCs in the pre-oxidation and coagulation system were significantly (P < 0.05) lower than those in the control. A significant (P < 0.05) difference in intracellular protein between the control and the coagulated systems was observed. Three-dimensional fluorescence excitation emission matrix (EEM) was employed to investigate the variations in extracellular organic matter (EOM) during flocs storage. The results indicated the presence of four peaks, representing protein-like substances, intermediate dissolved microbial metabolites, fulvic and humic-like compounds in the Fe2+/PS process. And the intensities of four peaks were all decreased in the Fe2+/PS system compared to those in the control. A low level of accumulated residual Fe of 0.28 mg/L was observed without posing potential environmental risk. The results showed that the M. aeruginosa cells were under stressful conditions after 3-d storage due to the decomposition of extracellular polymeric substances (EPSs) and the insufficient supply of nutrients. However, SEM results indicated that no significant alteration in cell morphology was observed. Therefore, with high removal of M. aeruginosa, low MCs concentrations, and trivial cell damage, the Fe2+/PS preoxidation-coagulation was proved to be an environmental-friendly method for cyanobacteria removal without yielding serious secondary pollution. This work will contribute to better understanding and managing the cyanobacteria-laden aquaculture water after pre-oxidation and coagulation.

Physiological and biochemical responses of Microcystis aeruginosa to phosphine (PH3) under elevated CO2.

Phosphine (PH3) is an important factor driving the outbreak of cyanobacterial blooms that produce toxic microcystin threating human health. To clarify the physiological and biochemical responses of cyanobacteria to PH3 under elevated CO2 concentration, Microcystis aeruginosa was used in the coupling treatment of 1000 ppmv CO2 and PH3 at different concentrations respectively. The chlorophyll a (Chl-a), carotenoid, net photosynthetic rate and total protein of M. aeruginosa exhibited evidently increasing tendency under the coupling treatment of 1000 ppmv CO2 and PH3 at different concentrations (7.51 × 10-3, 2.48 × 10-2, 7.51 × 10-2 mg/L). The coupling treatments resulted in the higher concentrations of Chl-a and carotenoid of M. aeruginosa, compared to those in the control and the treatment with CO2 alone, and their enhancement increased with the increase in PH3 concentrations. The total antioxidant capacity (T-AOC) in the coupling treatment with CO2 and PH3 of 2.48 × 10-2 mg/L and 7.51 × 10-3 mg/L showed increasing tendency, compared to the treatment with PH3 alone. Additionally, the coupling treatment with 1000 ppmv CO2 and PH3 also altered the pH and DO level in the culture medium. In this regard, the coupling treatment with CO2 and PH3 at an appropriate concentration can enhance the resistance of M. aeruginosa to PH3 toxicity and is beneficial to the reproduction of M. aeruginosa, presumably resulting in potential for the outbreak of cyanobacteria bloom. Given the concern about global warming and the increase in atmospheric CO2 level, our research laid a foundation for the scientific understanding of the correlation between PH3 and cyanobacteria blooms.

Role of the receptor tyrosine kinase Axl in hepatocellular carcinoma and its clinical relevance.

The receptor tyrosine kinase Axl and its ligand Gas6 regulate fundamental biological processes, including cell proliferation, survival and motility, through multiple downstream signaling pathways. Evidence to date suggests that aberrant Axl expression frequently occurs in many malignancies, including hepatocellular carcinoma, and that this is critical for promoting cell proliferation, migration, angiogenesis and metastasis. Moreover, deregulated Axl expression or activation is reportedly associated with resistance to cancer drugs and targeted cancer therapies. Thus, Axl inhibitors may represent a novel therapeutic approach for cancer treatment. This Review summarizes the latest advances concerning the biological role of Axl in hepatocellular carcinoma and its potential clinical relevance.

Phosphine production in anaerobic wastewater treatment under tetracycline antibiotic pressure.

The influence of tetracycline (TC) antibiotics on phosphine (PH3) production in the anaerobic wastewater treatment was studied. A lab-scale anaerobic baffled reactor with three compartments was employed to simulate this process. The reactor was operated in a TC-absence wastewater and 250µg/L TC-presence wastewater for three months after a start-up period, respectively. The responses of pH, oxidation-reduction potential (ORP), chemical oxygen demand (COD), total phosphorus (TP), enzymes activity (dehydrogenase and acid phosphatase), and microbial community were investigated to reveal the effect of TC on PH3 production. Results suggested that the dehydrogenase (DH) activity, acid phosphatase (ACP) activity and COD have positive relationship with PH3 production, while pH, ORP level and the TP in liquid phase have negative relationship with PH3 production. With prolonged TC exposure, decrease in pH and increase in DH activity are beneficial to PH3 production, while decrease in COD and ACP activity are not the limiting factors for PH3 production.

Preparation and biocompatibility of demineralized bone matrix/sodium alginate putty.

Demineralized bone matrix (DBM) powder is widely used for bone regeneration due to its osteoinductivity and osteoconductivity. However, difficulties with handling, tendency to migrate from graft sites and lack of stability after surgery sometimes limit the clinical utility of this material. In this work, the possibility of using sodium alginate (ALG) carrier to deliver DBM powder was assessed. DBM-ALG putty with the DBM:ALG weight ratio of 5:5, 6:4, 7:3, 8:2 were prepared, respectively. The properties of the formed composite, including discrete degree, washout property, pH, equilibrium swelling as well as cytotoxicity in vivo, were adopted to ascertain the optimal ratio of DBM and ALG. The discrete diameter increased from 1.25 cm (5:5) to 2.08 cm (8:2) with the increase of DBM content. There was significant difference between the 8:2 group and the other groups in discrete diameter. The ratio of DBM had a significant effect on the swelling value. The pH of composites showed an increase trend with the DBM ratio's increase, when the ratio reached 7:3, the pH (7.22) was approximately equal to the body fluid. The proliferation of MC3T3-E1 cells was inhibited in the 5:5, 6:4 and 7:3 groups, while a slightly increased in the 8:2 group. The DBM-ALG with the optimal ratio of 7:3 was confirmed based on the results of the above mentioned. The histocompatibility of DBM-ALG (7:3) was examined using a rat model in which the materials were implanted subcutaneously, compared with the polyethylene, ALG and DBM. The study in vivo showed DBM-ALG (7:3) had a lower inflammatory response than DBM, a higher vascularization than ALG. The osteoinduction of DBM-ALG (7:3) was evaluated by co-culturing with MC3T3-E1 in vitro, compared with the DMEM, ALG and DBM. The results indicated calcification area in the DBM-ALG group was similar to that in the DBM group, larger than ALG group and DMEM group. The DBM-ALG (7:3) putty is promising as a directly injectable graft for repair of bone defect.

Nitrate adsorption from aqueous solutions by calcined ternary Mg-Al-Fe hydrotalcite.

Calcined ternary hydrotalcite like compounds had been synthesized by co-precipitation and calcined at 450 °C for 6 h. It had been applied into the nitrate removal from aqueous solutions. Various factors during adsorption process, such as chemical composition of adsorbents, adsorbent dosage, initial concentration of nitrate, initial pH and co-existing anions on nitrate adsorption had been investigated. It was found that 1.5 g/L CHTlcs (Mg/Al/Fe molar ratio = 3:0.1:0.9) could achieve ideal adsorption efficiency at an initial nitrate concentration of 100 mg/L. The value of pH had little effect on nitrate adsorption. The co-existing anions had the inhibitory effect on nitrate adsorption, which was in the order of PO43- > SO42- > Cl- > ClO4-. The batch adsorption studies showed that experimental data were well described by the pseudo-second-order kinetic model and Langmuir isotherm model, and the maximum isotherm adsorption capacity was 123.305 mg/g. The adsorption of nitrate was a spontaneous exothermic process with the reduction of entropy. The proposed adsorption mechanism obtained from characterization was that CHTlcs uptake nitrate through reconstruction effect and adsorption on external surface.

Uncovering novel loci for mesocotyl elongation and shoot length in indica rice through genome-wide association mapping.

MAIN CONCLUSION: Totally, 23 loci were detected, and 383 candidate genes were identified, and four of these candidate genes, Os01g0392100, Os04g0630000, Os01g0904700 and Os07g0615000, were regarded as promising targets. Direct-seeding cultivation is becoming popular in rice (Oryza sativa L.)-planting countries because it is labor- and time-efficient. However, low seedling establishment and slow seedling emergence have restricted the application and popularity of the technique. Mesocotyl elongation and shoot length are two important traits that can enhance rice seedling emergence. A single nucleotide polymorphism (SNP) is a genome sequence variation caused by a single base within a population, and SNPs evenly distributed throughout the genomes of plant species. In this study, a genome-wide association study (GWAS), based on 4136 SNPs, was performed using a compressed mixed linear model that accounted for population structure and relative kinship to detect novel loci for the two traits. Totally, 23 loci were identified, including five loci located known QTLs region. For the mesocotyl elongation, 17 major loci were identified, explaining ~19.31 % of the phenotypic variation. For the shoot length, six major loci were detected, explaining ~ 39.79 % of the phenotypic variation. In total, 383 candidate genes were included in a 200-kb genomic region (± 100 kb of each locus). Additionally, 32 SNPs were identified in 30 candidate genes. Relative expression level analyses indicated that four candidate genes containing SNP variations, Os01g0392100, Os04g0630000, Os01g0904700 and Os07g0615000, represented promising targets. Finally, eight elite accessions with long mesocotyl and shoot lengths were chosen as breeding donors for further rice direct-seeding variety modifications.

Genetic variation and association mapping for 12 agronomic traits in indica rice.

BACKGROUND: Increasing rice (Oryza sativa L.) yield is a crucial challenge for modern agriculture. The ideal plant architecture is considered to be critical to enhance rice yield. Elite plant morphological traits should include compact plant type, short stature, few unproductive tillers, thick and sturdy stems and erect leaves. To reveal the genetic variations of important morphological traits, 523 germplasm accessions were genotyped using the Illumina custom-designed array containing 5,291 single nucleotide polymorphisms (SNPs) and phenotyped in two independent environments. Genome-wide association studies were performed to uncover the genotypic and phenotypic variations using a mixed linear model. RESULTS: In total, 126 and 172 significant loci were identified and these loci explained an average of 34.45% and 39.09% of the phenotypic variance in two environments, respectively, and 16 of 298 (~5.37%) loci were detected across the two environments. For the 16 loci, 423 candidate genes were predicted in a 200-kb region (±100 kb of the peak SNP). Expression-level analyses identified four candidate genes as the most promising regulators of tiller angle. Known (NAL1 and Rc) and new significant loci showed pleiotropy and gene linkage. In addition, a long genome region covering ~1.6 Mb on chromosome 11 was identified, which may be critical for rice leaf architecture because of a high association with flag leaf length and the ratio of flag leaf length and width. The pyramid effect of the elite alleles indicated that these significant loci could be beneficial for rice plant architecture improvements in the future. Finally, 37 elite varieties were chosen as breeding donors for further rice plant architectural modifications. CONCLUSIONS: This study detected multiple novel loci and candidate genes related to rice morphological traits, and the work demonstrated that genome-wide association studies are powerful strategies for uncovering the genetic variations of complex traits and identifying candidate genes in rice, even though the linkage disequilibrium decayed slowly in self-pollinating species. Future research will focus on the biological validation of the candidate genes, and elite varieties will also be of interest in genome selection and breeding by design.

Preparation of porous PLA/DBM composite biomaterials and experimental research of repair rabbit radius segmental bone defect.

Bone substitutes are used in wide range of orthopaedic application. An ideal bone substitute should exhibit superior osteoinductive and osteoconductive properties. Neither bio-derived materials nor synthetic materials can meet the needs of an ideal bone substitute. Preparation of composite materials is a promising way to improve properties of biomaterial. In this study, the porous poly lactic acid (PLA)/demineralized bone matrix (DBM) composite biomaterials prepared by supercritical CO2 technique were implanted to repair rabbit radius segmental bone defect. By comparing with PLA and bone autograft, the X-ray result and histological analysis showed the repair effect of PLA/DBM porous composite materials is significantly better than that of the PLA group and the blank control group, and is similar to autologous bone. The PLA/DBM can promote the healing of bone defects and can be used as a kind of ideal alternative materials to repair bone defects.

Insights into the inhibitory effects of trichloroisocyanuric acid disinfectant on the phototransformation of polypropylene microplastics.

The chemical components in the natural aquatic environment have the potential to be involved in phototransformation of microplastics (MPs). Little information is available regarding the mediation effects of artificially introduced chemicals on MP phototransformation, especially those used in aquaculture water that are vulnerable to human interference. Herein, this study investigated the phototransformation process and mechanism of polypropylene microplastic (PP MPs) in presence of trichloroisocyanuric acid (TCCA) disinfectant with unique properties unlike the conventional inorganic chlorine disinfectants. The results showed that the presence of TCCA inhibited the surface photooxidation of PP MPs. Analysis of PP MP surface and reaction filtrate indicated that the inhibitory effects were likely derived from TCCA derivatives and the weakening in promoting effect of polypropylene microplastic-derived dissolved organic matter (PP-DOM) as photolytic byproducts, with the more important role of free chlorine in initial period and that of other chlorine species (i.e., the adsorbed chloride ions (Cl-), newly formed carbon-chlorine (CCl) bonds, chlorinated cyanurates, and chlorinated products) in middle and later period. The study highlights for the first time the important role of chlorine species derived from TCCA in phototransformation process of co-existed PP MPs and proposes a previously unrecognized phototransformation pathway, which will provide a new understanding and knowledge for the environmental behavior of MPs in aquaculture environment.

GC-MS Combined with Proteomic Analysis of Volatile Compounds and Formation Mechanisms in Green Teas with Different Aroma Types.

Aroma is one of the key factors for evaluating the quality of green tea. A tender aroma (NX) and floral-like aroma (HX) are two types of high-quality aroma of green tea. In this work, the different aroma types of baked green tea were classified by sensory evaluation. Then, seven tea samples with a typical tender or floral-like aroma were selected for further volatile component analysis by GC-MS. A total of 43 aroma compounds were identified in two different aroma types of baked green tea samples. The PCA showed that linalool, geraniol, 3-hexenyl butyrate, and 3-hexenyl hexanoate were the major volatiles contributing to the HX. On the other hand, most of the alcohol volatiles, such as 1-octanol, 1-octen-3-ol, 1-dodecanol, 1-hexadecanol, phenylethyl alcohol, benzyl alcohol, aldehydes and some hydrocarbons contributed more to the NX. In addition, the chemical composition analysis showed that the content of free amino acids was higher in NX green tea samples, while the content of catechins was relatively higher in HX tea samples. A proteomic analysis revealed that most of the enzymes involved in VPBs pathways, such as phenylalanine ammonialyase, peroxidase, and shikimate-O-hydroxycinnamoyl transferase, were more abundant in NX than in HX tea samples. These results laid a foundation for the aroma formation mechanism of different aroma types of baked green tea and provided some theoretical guidance for the breeding of specific aroma varieties.

Recent advances in swine wastewater treatment technologies for resource recovery: A comprehensive review.

Swine wastewater (SW), characterized by highly complex organic and nutrient substances, poses serious impacts on aquatic environment and public health. Furthermore, SW harbors valuable resources that possess substantial economic potential. As such, SW treatment technologies place increased emphasis on resource recycling, while progressively advancing towards energy saving, sustainability, and circular economy principles. This review comprehensively encapsulates the state-of-the-art knowledge for treating SW, including conventional (i.e., constructed wetlands, air stripping and aerobic system) and resource-utilization-based (i.e., anaerobic digestion, membrane separation, anaerobic ammonium oxidation, microbial fuel cells, and microalgal-based system) technologies. Furthermore, this research also elaborates the key factors influencing the SW treatment performance, such as pH, temperature, dissolved oxygen, hydraulic retention time and organic loading rate. The potentials for reutilizing energy, biomass and digestate produced during the SW treatment processes are also summarized. Moreover, the obstacles associated with full-scale implementation, long-term treatment, energy-efficient design, and nutrient recovery of various resource-utilization-based SW treatment technologies are emphasized. In addition, future research prospective, such as prioritization of process optimization, in-depth exploration of microbial mechanisms, enhancement of energy conversion efficiency, and integration of diverse technologies, are highlighted to expand engineering applications and establish a sustainable SW treatment system.

GL5.2, a Quantitative Trait Locus for Rice Grain Shape, Encodes a RING-Type E3 Ubiquitin Ligase.

Grain weight and grain shape are important traits that determine rice grain yield and quality. Mining more quantitative trait loci (QTLs) that control grain weight and shape will help to further improve the molecular regulatory network of rice grain development and provide gene resources for high-yield and high-quality rice varieties. In the present study, a QTL for grain length (GL) and grain width (GW), qGL5.2, was firstly fine-mapped into a 21.4 kb region using two sets of near-isogenic lines (NILs) derived from the indica rice cross Teqing (TQ) and IRBB52. In the NIL populations, the GL and ratio of grain length to grain width (RLW) of the IRBB52 homozygous lines increased by 0.16-0.20% and 0.27-0.39% compared with the TQ homozygous lines, but GW decreased by 0.19-0.75%. Then, by analyzing the grain weight and grain shape of the knock-out mutant, it was determined that the annotation gene Os05g0551000 encoded a RING-type E3 ubiquitin ligase, which was the cause gene of qGL5.2. The results show that GL and RLW increased by 2.44-5.48% and 4.19-10.70%, but GW decreased by 1.69-4.70% compared with the recipient. Based on the parental sequence analysis and haplotype analysis, one InDel variation located at -1489 in the promoter region was likely to be the functional site of qGL5.2. In addition, we also found that the Hap 5 (IRBB52-type) increased significantly in grain length and grain weight compared with other haplotypes, indicating that the Hap 5 can potentially be used in rice breeding to improve grain yield and quality.