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Wastewater with residual streptomycin sulphate usually contains high content of ammonia-nitrogen. However, the biological removal process of ammonia-nitrogen under streptomycin sulphate circumstance was unclear. In this study, short-term and long-term effects of streptomycin sulphate on biological nitrification systems, including AOB, NOB, SAOR, SNOR and SNPR, were evaluated comprehensively. The results indicated IC50 for AOB and NOB were 7.5 and 6.6 mg/L. SAOR and SNPR could be decreased to 3.43 ± 0.52 mg N/(g MLSS·h) and 0.24 ± 0.03 mg N/(g MLSS·h) while the addition of streptomycin sulphate was 10 mg/L. When streptomycin sulphate addition was stopped, nitrification ability recovered slightly, SAOR and SNPR increased to 9.37 ± 0.36 mg N/(g MLSS·h) and 1.66 ± 0.49 mg N/(g MLSS·h), respectively. The protein of EPS increased gradually during the acclimatization process, and the maximal protein value was 68.24 mg/g MLSS on the 100th day, however, no significant change of polysaccharose was observed during the acclimatization process. High abundance of ARGs and intI1 was detected in effluent and sludge of the biological treatment system. The maximal relative abundance of aadA1 in the sludge appeared on the 140th day, and increased by 0.99 orders of magnitude. Biological diversity decreased significantly during the acclimatization process, relative abundance of nitrosomonas was changed from 9.07% to 38.68% on the 61st day, while relative abundance of nitrobacter was changed from 1.30% to 0.64%. It should be noted that relative abundances of nitrosomonas and nitrobacter were reduced to 16.17% and 0.25% on the 140th day. This study would be helpful for nitrogen removal in wastewater with antibiotic.

At present, biomass-based polymers can be applied in several fields, such as medicine, biology, aerospace and so on. Due to their good biodegradability, more environmentally friendly products with desirable functions can be designed and processed by people. Therefore, it can be a potential candidate to solve the serious environmental pollution caused by using petroleum-based polymeric materials in the production process. In this article, cellulose, lignin and vegetable oil are taken as examples, all of which are typical biomass-based polymer monomers, by reviewing their synthesis process and applications based on the recent studies on their production, modification and performance enhancements. The properties of final products in the industry stand out compared with many other products synthesized from petroleum-based polymeric materials as there exist different scientific modification methods to synthesize materials with desirable properties. One of the most practical applications is that all of them can be used to synthesize composite materials with enhanced properties. However, more research is required to quantify the environmental benefits and reduce the costs of biomass-based polymers so that we can make full use of biomass-based polymers and even expand their application fields. The article analyzed the application of biomass-based polymers and proposed some suggestions for its future development to help solve the present environmental problems.

The phenotypic color of seeds is a complex agronomic trait and has economic and biological significance. The genetic control and molecular regulation mechanisms have been extensively studied. Here, we used a multi-omics strategy to explore the color formation in soybean seeds at a big-data scale. We identified 13 large quantitative trait loci (QTL) for color with bulk segregating analysis in recombinant inbreeding lines. GWAS analysis of colors and decomposed attributes in 763 germplasms revealed associated SNP sites perfectly falling in five major QTL, suggesting inherited genetic control on color during natural selection. Further transcriptomics analysis before and after color accumulation revealed 182 differentially expression genes (DEGs) in the five QTL, including known genes CHS, MYB, and F3’H involved in pigment accumulation. More DEGs with consistently up- or down-regulation were identified as shared regulatory genes for two or more color formations while some DEGs were only for a specific color formation. For example, five up-regulated DEGs in QTL qSC-3 were in flavonoid biosynthesis responsible for black and brown seed. The DEG (Glyma.08G085400) was identified in the purple seed only, which encodes gibberellin 2-beta-dioxygenase in the metabolism of colorful terpenoids. The candidate genes are involved in flavonoid biosynthesis, transcription factor regulation, gibberellin and terpenoid metabolism, photosynthesis, ascorbate and aldarate metabolism, and lipid metabolism. Seven differentially expressed transcription factors were also found to regulate color formation, including a known MYB. The finds expand QTL and gene candidates for color formation, which could guide to breed better cultivars with designed colors.

Interstitial stromal cells play critical roles in muscle development, regeneration and repair and we have previously reported that Hoxa11 and Hoxd11 are expressed in the interstitial cells of muscles attached to the zeugopod, and are crucial for the proper embryonic patterning of these muscles. Hoxa11eGFP expression continues in a subset of muscle interstitial cells through adult stages. The induction of Hoxa11-CreERT2-mediated lineage reporting (Hoxa11iTom) at adult stages in mouse results in lineage induction only in the interstitial cells. However, Hoxa11iTom+ cells progressively contribute to muscle fibers at subsequent stages. The contribution to myofibers exceeds parallel Pax7-CreERT2-mediated lineage labeling. Nuclear-specific lineage labeling demonstrates that Hoxa11-expressing interstitial cells contribute nuclear contents to myofibers. Crucially, at no point after Hoxa11iTom induction are satellite cells lineage labeled. When examined in vitro, isolated Hoxa11iTom+ interstitial cells are not capable of forming myotubes, but Hoxa11iTom+ cells can contribute to differentiating myotubes, supporting Hox-expressing interstitial cells as a new population of muscle progenitors, but not stem cells. This work adds to a small but growing body of evidence that supports a satellite cell-independent source of muscle tissue in vivo.

This is the first study on the microbiome signature of endophytes in wheat seed response to wheat dwarf bunt caused by Tilletia controversa Kühn. Some antagonistic microbes suppressed the germination of teliospores of the pathogen significantly, which will provide clues for future studies against wheat dwarf bunt. Collectively, this research first advances the understanding of the microbial assembly of wheat seed upon exposure to the fungal pathogen ( T. controversa ) infection.

In orthodontics, mechanical stress plays an important role in the process of bone remodeling. Mechanical stress has an effect on osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). However, the mechanism remains to be studied. The aim of this study is to investigate the effects of demethyltransferase fat mass and obesity-associated (FTO) on osteogenic differentiation of BMSCs under mechanical stress condition.The rat BMSCs were cultured in vitro, followed by flow cytometry to identify the cell surface antigens. Osteogenic differentiation of BMSCs was induced by mechanical stress by using the flexcell tension system for 6 h every day and 3 days in total. BMSCs were transfected by using plasmid for FTO knockdown. The expression level of FTO, hypoxia-inducible factor (HIF)-1α, runt-related transcription factor 2 (RUNX2), bone morphogenetic proteins (BMPs) and alkaline phosphatase (ALP) were measured by real-time qPCR, western blotting. ALP activity were determined by ALP staining assays. The expression of FTO and HIF-1α in BMSCs with mechanical stress were significantly higher than BMSCs without mechanical stress, also, the expression of osteogenic differentiation markers were higher in BMSCs with mechanical stress. Knockdown of FTO decreased expression of osteogenic differentiation marker and ALP activity in stretched BMSCs. In addition, the expression of HIF-1α was decreased after knocking down FTO.FTO promotes the expression of HIF-1α and osteogenic differentiation under the condition of mechanical stress. This finding may facilitate the clinical application of orthodontics and the mechanism research of mechanical stress-induced osteogenesis.

Adult skeletal muscle possesses remarkable regenerative capacity. This is attributed to tissue-specific stem cells, satellite cells. Interstitial stromal cells also play critical roles in muscle, and we have previously reported that Hoxa11 and Hoxd11, expressed in the interstitial cells of muscles that attach to the zeugopod (radius and ulna), are critical for the proper patterning and development of these muscles during embryogenesis. Using a Hoxa11eGFP knock-in reporter, we show that expression continues in a subset of muscle interstitial cells through adult stages. Using Hoxa11-CreERT2 mediated lineage reporting induced at adult stages, we observe lineage initiation only in the interstitial cells of muscle, as expected. However, this Hoxa11-expressing interstitial cell lineage progressively contributes to muscle fibers at postnatal and adult stages. The contribution to these muscles at adult homeostasis significantly exceeds parallel Pax7-CreERT2 mediated lineage labeling performed in parallel. To confirm that interstitial cell nuclear contents are contributed to muscle fibers, we additionally used the nuclear specific lineage reporter, ROSA-LSL-H2BmCherry with Hoxa11-CreERT2 and observe that Hoxa11-expressing interstitial cells contribute their nuclei to myofibers. Hox lineage contribution is observed into all four muscle sub-types over months of lineage labeling. At no point after Hoxa11-mediated lineage induction do we observe lineage labeling into Pax7-expressing satellite cells. This adds to a small but growing body of evidence that supports a satellite cell-independent source of muscle tissue in vivo.Summary StatementHoxa11 expression marks a novel population of muscle interstitial cells capable of extensive, satellite cell-independent contribution to skeletal muscle fibers during adult homeostasis.

Rhizosphere soil microorganisms have great agricultural importance. To explore the relationship between rhizosphere microorganisms and the disease incidence, and to optimize the concentration of difenoconazole fungicide for the control of wheat dwarf bunt, caused by Tilletia controversa Kühn, the rhizosphere microorganisms were characterized based on sequencing methods. We found that the disease incidence correlated with the relative abundance of some microbial communities, such as Acidobacteria, Nocardioides, Roseiflexaceae, Pyrinomonadaceae, and Gemmatimonadaceae. Actinobacteria showed significant differences in the infected soils when compared to the control soils, and the relative abundance of Acidobacteria, Pyrinomonadaceae, Gemmatimonadaceae, and Saccharimonadales populations was distinctly higher in the T. controversa-inoculated group than in the control group. The members of Dehalococcoidia, Nitrosomonadaceae, and Thermomicrobiales were found only in T. controversa-inoculated soils, and these taxa may have potential effects against the pathogen and contribute to disease control of wheat dwarf bunt. In addition, for T. controversa-infected plants, the soil treated with difenoconazole showed a high relative abundance of Proteobacteria, Actinobacteria, Ascomycota, Basidiomycota, Mortierellomycota, and Olpidiomycota based on the heatmap analysis and ANOVA. Our findings suggest that the optimized concentration of fungicide (5% recommended difenoconazole) exhibits better control efficiency and constant diversity in the rhizosphere soil.

A complex dataset with 140 sampling events was generated using triple quadrupole gas chromatography-mass spectrometer to track the occurrence of 95 odorants in raw and finished water from 98 drinking water treatment plants in 31 cities across China. Data analysis identified more than 70 odorants with concentrations ranging from not detected to thousands of ng/L. In raw water, Pearson correlation analysis determined that thioethers, non-oxygen benzene-containing compounds, and pyrazines were classes of chemicals that co-occurred, and geosmin and p(m)-cresol, as well as cyclohexanone and benzaldehyde, also co-occurred, indicating similar natural or industrial sources. Based on classification and regression tree analysis, total dissolved organic carbon and geographical location were identified as major factors affecting the occurrence of thioethers. Indoles, phenols, and thioethers were well-removed through conventional and advanced treatment processes, while some aldehydes could be generated. For other odorants, higher removal was achieved by ozonation-biological activated carbon (39.3%) compared to the conventional treatment process (14.5%). To our knowledge, this is the first study to systematically identify the major odorants in raw water and determine suitable treatment strategies to control their occurrence by applying data analytics and statistical methods to the complex dataset. These provide informative reference for odor control and water quality management in drinking water industry.

Biofilms drive crucial ecosystem processes in rivers. This study provided the basis for overall quantitative calculations about the contribution of biofilms to the nitrogen cycle. At the early stage of biofilm formation, dissolved oxygen (DO) could penetrate the biofilms. As the biofilm grew and the thickness increased, then the mass transfer of DO was restricted. The microaerobic layer firstly appeared in biofilm under the turbulent flow conditions, with the appearance of the microaerobic and anaerobic layer, the nitrification and denitrification reaction could proceed smoothly in biofilm. And the removal efficiency of total nitrogen (TN) increased as the biofilm matured. Under the turbulent flow conditions, mature biofilms had the smallest thickness, but the highest proportion the anaerobic layer to the biofilm thickness, the highest density, and the highest nitrogen removal efficiency. However, the nitrogen removal efficiency of biofilm was the lowest under laminar flow conditions. The difference of layered structure of biofilm and the DO flux in biofilm explained the difference of nitrogen migration and transformation in river water under different hydrodynamic conditions. This study would help control the growth of biofilm and improve the nitrogen removal capacity of biofilm by regulating hydrodynamic conditions.

Microbial biofilms are common on abiotic and biotic surfaces, especially in rivers, which drive crucial ecosystem processes. The microorganisms of biofilms are surrounded by a self-produced extracellular polymeric substance (EPS). In this study, we investigated the effects of different hydrodynamic conditions on the composition, spatiotemporal distribution of different extracellular polymeric substances, and the architecture of biofilms. Multidisciplinary methods offer complementary insights into complex architecture correlations in biofilms. The biofilms formed in turbulent flow with high shear force were thin but dense. However, the biofilms formed under laminar flow conditions were thick but relatively loose. The thickness and compactness of the biofilms formed in the transitional flow were different from those of the other biofilms. The compact structure of the biofilm helped to resist shear forces to minimize detachment. Under the turbulent flow condition, bacteria, exopolysaccharides, and extracellular proteins permeated through the biofilm, and more extracellular polysaccharides enveloped bacteria and extracellular proteins. However, under the transitional flow condition, the extracellular polysaccharides and proteins were fewer than those under the turbulent flow condition; bacteria and algae were seen more prominently in the upper layer of the biofilm. Under the laminar flow condition, the distribution of extracellular polysaccharides, extracellular proteins, and bacteria was relatively uniform throughout the biofilm. The number of extracellular polysaccharides was greater than that of extracellular proteins. The total number of EPS in the biofilm was the largest under turbulent flow condition, followed by that under transitional flow condition and then under laminar flow condition. This study also observed that soluble EPS (S-EPS) were secreted first, followed by loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS). In particular, the adhesion of LB-EPS and flocculation capability of TB-EPS play some role in regulating biofilm formation. This study would help to perfect the five-stages theory of biofilm formation.

Anammox has been widely used for the treatment of nitrogen wastewater. However, the problem of stable NO2− supplement becomes one of the limiting factors. It is an effective method to obtain NO2− by denitrifying the NO3−, including the by-product of Anammox. In this study, NO2− was reinforced by bio-electrochemical system (BES) through the reaction of partial denitrification in situ in an Anammox reactor. Our results showed that both NO3− and NO2− can be reduced on the cathode with different Coulombic efficiencies. The reduction of NO3− amount increased with an increase in Inf-NO3−, which was greater than that of NO2−. The conversion amount of NO3− was 2.50% ± 17.25% to the theoretical Eff-NO3−, and the maximum reduction amount was 23.24% with the highest Coulombic efficiency of 3.56%. High throughput results showed that denitrifying bacteria, such as Limnobacter, Thauera, Denitratisoma, Nitrosomonas and Nitrospira, were attached to the cathode surface and in Anammox granular sludge. This study showed that NO2− can be supplied by reducing the by-product NO3− with denitrification cathode at Anammox environment in-situ.

Disgusting fishy odor problems have become a major concern in drinking water quality, and are commonly related to algal proliferation in source water. Unlike the typical musty/earthy odorants 2-methylisoborneol (MIB) and geosmin, identification of the corresponding fishy odorants is still a big challenge. In this study, two species of fishy-odor-producing algae, Ochromonas sp. and Cryptomonas ovate, were cultured to explore the odor production characteristics and typical odorants. When algae were ruptured in the stationary and decline phases, fishy odor intensities of 4 to 8 characterized by FPA were produced. However, some frequently reported aldehydes that could cause fishy odor, including n-hexanal, 2-octenal, heptanal, 2,4-heptanal and 2,4-decadienal, were not detected in either of the cultured algae. The possible fishy odor-causing compounds were further identified by combining gas chromatography-olfactometry (GC-O/MS) and comprehensive two-dimensional gas chromatography (GC × GC-TOFMS) using retention indices (RIs). From GC-O/MS analysis, twelve and six olfactometry peaks with various odor characteristics were identified in Ochromonas sp. and Cryptomonas ovate, respectively, of which three and two olfactometry peaks showed fishy odor characteristics. 2-Nonenal, 2,4-octadienal, fluorene and 2-tetradecanone were identified as fishy odorants in Ochromonas sp., and 1-octen-3-ol, 6-methyl-5-hepten-2-one, 1-octen-3-one, 2-nonenal and 2,4-octadienal were identified in Cryptomonas ovate. Other identified compounds, including butyl butanoate (fragrant odor), ionone (fragrant odor), bis (2-chloroisopropyl) ether (chemical odor) etc., did not show fishy features. Therefore, the fishy odor might be a synthetic and comprehensive odor, which resulted from the combination of different odorants and their synergistic effects. The results of this study will be helpful for understanding fishy odor problems, which will provide support for fishy odor management and control in the drinking water industry.

Aim: Mechanical strain plays a crucial role in bone formation and remodeling. Hypoxia-inducible factor (HIF)-1α and TWIST are upstream of master regulators of osteogenesis, including runt-related transcription factor 2 (RUNX2) and bone morphogenetic proteins (BMPs). This study investigated the effect of the HIF-1α-TWIST pathway on cyclic mechanical stretch-induced osteogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs) and the underlying mechanism. Materials and Methods: BMSCs were isolated from bone marrow derived from the femurs and humeri of Sprague-Dawley rats. Osteogenic differentiation of BMSCs was induced by applying cyclic mechanical stretch using the Flexcell Tension System. HIF-1α and TWIST were knocked down using recombinant lentiviral vectors. Osteogenic differentiation was evaluated by real-time qPCR, western blotting, and the alkaline phosphatase (ALP) activity assay. Results: Cyclic mechanical stretch increased ALP activity and expression of HIF-1α and TWIST in BMSCs. Knockdown of HIF-1α decreased TWIST expression in stretched BMSCs. Moreover, knockdown of HIF-1α or TWIST enhanced cyclic mechanical stretch-induced osteogenic differentiation of BMSCs. In addition, knockdown of TWIST increased expression of RUNX2 and BMP2 in stretched BMSCs. Conclusions: The HIF-1α-TWIST signaling pathway inhibits cyclic mechanical stretch-induced osteogenic differentiation of BMSCs. This finding may facilitate cell and tissue engineering for clinical applications.

Revealing the main contributors to septic odor is a challenge since diverse compounds are responsible for this odor, and there might exist synergistic effects among different odorants. In this study, based on a reconstitution evaluation, the contribution of eighteen odorants identified in Huangpu River source water to the septic odor was explored. The reconstitution test result showed that the three typical odorants, including bis(2‑chloroisopropyl) ether (BCIE), diethyl disulfide (DEDS) and dimethyl disulfide (DMDS), with respective average odor activity values (OAVs) of 2.35, 1.65 and 0.78, only contributed 61 ± 3% of the FPA intensity for septic odor in Huangpu source water. At a BCIE concentration of 50 ng/L, synergistic effect for the septic odor occurred at 10 ng/L for geosmin and 20 ng/L for 2‑methylisoborneol (MIB), showing that coexisting musty odorants could enhance the septic odor intensity caused by some typical odorants. When both geosmin and MIB, with an average OAV of 4.54 and 1.38, were further included in addition to the three typical odorants, 88 ± 4% of the septic odor in Huangpu River source water could be explained. With addition of the remaining odorants with much lower OAVs (0.23), 94 ± 2% of the septic odor could be explained. The musty odor was not affected by the presence of the co-existing odorants at the concentration levels of the present study. This study indicated that the overall odor of water contaminated with musty and septic odorants is a combination of both concentrations of individual contaminants and their synergistic effects. This is the first study to reveal the synergistic effects of typical musty odorants on septic odor, and the results of this study demonstrated that the synergistic effects of other odorants should be considered when dealing with the septic odor in drinking water.

Taste and odor problems in drinking water have long been plaguing many water utilities and the public. Even though many odorants have been reported, up to now, identification of the odor-causing compounds is still a challenge for the water industry. In this study, 22 typical reported odor compounds with similar odor characteristics were selected as the training set to build the linear quantitative structure odor relationship (QSOR) model by the partial least squares (PLS) method. The logarithm of the odor threshold (OT) value divided by the molecular weight of the responsible compound (pOT) was selected as the response descriptor to express odor characteristics. The resulting good statistical results, with R2 (correlation coefficient) = 0.8988, RMSE (root mean square error) = 0.4374, XR2 (cross-validated correlation coefficient) = 0.8133, and XRMSE (cross-validated root mean square error) = 0.5993, indicate that the odor thresholds of potential odorants with similar or distinguishable odors could be predicted using the model with corresponding descriptor data of known-structure odorants. Moreover, external validation was also conducted using the nonlinear binary QSOR method, where the overall binary QSOR accuracy remained stable (around 90%) regardless of the chosen threshold values. By using the validated QSOR model, the pOT of the set of 8 test compounds was successfully predicted with good correlation to their experimental pOT values. This study could provide a novel and convenient way to screen the potential odorants from innumerable candidate chemicals.

Background: To improve the microbial safety of drinking water, an arrangement of O3–BAC with rear sand filtration (O3–BAC–sand) has been proposed. In this study, efforts were devoted to evaluate the benefits and drawbacks of O3–BAC–sand in a full-scale water treatment plant. The performance of the two configurations was compared in terms of particles, turbidity, CODMn and typical odorants and pesticides. Results: The O3–BAC–sand yielded lower turbidity but higher CODMn (by approximately 7%) in the finished water than regular O3–BAC (sand–O3–BAC). Both systems removed odors in raw water; however, sand–O3–BAC was more effective on septic and musty odorants. The total pesticide removals by sand–O3–BAC and O3–BAC–sand were 78% and 72%, respectively; though the latter had shorter activated carbon durable years. Conclusion: The re-location of the sand filter would sacrifice the BAC efficiency in removals of organic matter and micropollutants. This tradeoff is a result of the loss of the particulate organic matter removal by sand filters, because locating the sand filter behind BAC causes particle load increase on BAC; some measures of enhanced coagulation should be suggested to improve the turbidity and particle removal. The study will be helpful for improvement of the O3–BAC process in drinking water treatment.

The microbial composition of dental caries may depend on age, diet, and geography, yet the effect of geography on these microbiomes is largely underexplored. Here, we profiled and compared saliva microbiota from 130 individuals aged 6 to 8 years old, representing both healthy children (H) and children with severe caries (C) from two geographical regions of China: Qingdao Guangzhou. First, the saliva microbiota exhibited profound differences in diversity and composition between the C and H groups. The caries microbiota featured a lower alpha diversity and more variable community structure than the healthy microbiota. Furthermore, the relative abundance of several genera (e.g., Lactobacillus, Gemella and Cryptobacterium) was significantly higher in the C group than in the H group. Next, geography dominated over disease status in shaping salivary microbiota, and a wide array of salivary bacteria was highly predictive of the individuals’ city of origin. Finally, we built a universal diagnostic model based on 14 bacterial species, which can diagnose caries with 87% and 85% accuracy within each city and 83% accuracy across cities. These findings demonstrated that despite the large effect size of geography, a universal model based on salivary microbiota has the potential to diagnose caries across human populations.

Dental caries is one of the most prevalent chronic oral diseases, affecting approximately half of children worldwide. The microbial composition of dental caries may depend on age, oral health, diet, and geography, yet the effect of geography on these microbiomes is largely underexplored. Here, we profiled and compared saliva microbiota from 130 individuals aged 6 to 8 years old, representing both healthy children (H group) and children with caries-affected (C group) from two geographical regions of China: a northern city (Qingdao group) and a southern city (Guangzhou group). First, the saliva microbiota exhibited profound differences in diversity and composition between the C and H groups. The caries microbiota featured a lower alpha diversity and more variable community structure than the healthy microbiota. Furthermore, the relative abundance of several genera (e.g., Lactobacillus, Gemella, Cryptobacterium and Mitsuokella) was significantly higher in the C group than in the H group (pStreptococcus mutans in populations is not very high, it could be regarded as a single biomarker to diagnose caries with decent accuracy. These findings demonstrated that despite the large effect size of geography, a universal model based on salivary microbiota has the potential to diagnose caries across the Chinese child population.

Sudden odor incidents occurring in the source water have been a severe problem for water suppliers. In order to apply emergency control measures effectively, it is necessary to identify the target compounds responsible for odor incidents rapidly. The present work identified the odorants and explored emergency disposal mechanisms for sudden and severe odors in the QT River's drinking water source (HZ city, China). Medicinal, chemical, septic, and musty odors with strong intensities were detected in the source water. The effect of conventional treatments of drinking water treatment plant (DWTP) on odors' removal was limited, which was evident by the presence of medicinal, chemical, and musty odors with moderate intensities in the effluent of DWTP. Total seventeen odorants were identified successfully in the source water of QT River and the effluent of DWTP. The measured OAVs and reconstituting the identified odorants explained 87%, 87%, 89%, and 94% of medicinal, chemical, septic, and musty odors, respectively, in the source water of the QT River and 90%, 87%, and 88% of medicinal, chemical, and musty odors in the effluent. Styrene, phenol, 2-chlorophenol, 2-tert-butylphenol, and 2-methylphenol were associated with the medicinal odor, while propyl sulfide, diethyl disulfide, propyl disulfide, and indole were related to the septic odor. Geosmin and 2-methylisoborneol (2-MIB) were responsible for the musty odor, and cyclohexanone, 1,4-dichlorobenzene, and nitrobenzene were involved with the chemical odor. Based on the characteristics of identified odorants, powdered activated carbon (PAC) was applied to control the odors in the QT River. The results indicated that the medicinal, chemical, septic, and musty odors could be removed entirely after adding 15 mg/L PAC, which effectively controlled emergency odor problems. Overall, the study would offer a scientific basis and operational reference for emergency odor management and control in DWTP with similar complicated odor incidents.

Objective This research investigated the biological role of isoprenylcysteine carboxyl methyltransferase (ICMT) in tongue squamous cell carcinoma (TSCC) progression meanwhile to explore the conceivable mechanism. Methods The mRNA and protein expression were measured using real-time PCR and Western blot. Cell proliferation, apoptosis, cycle distribution, migration and invasion were evaluated by CCK-8 assay, flow cytometry, wound-healing assay and transwell assay. The anti-tumor activity of ICMT silencing was observed in nude mice. Results Our results indicated that silencing of ICMT-mediated methylation effectively inhibited TSCC cells proliferation in vitro and reduced tumor growth in vivo. Moreover, ICMT knockdown also induced cell apoptosis and cell cycle arrest of both CAL-27 and SCC-4 cells. In addition, CAL-27 and SCC-4 cells migration and invasion were weakened by ICMT siRNA. Mechanistically, ICMT deficiency significantly decreased the K-Ras and RhoA membrane targeting localization, leading to the suppression of K-Ras- and RhoA-mediated downstream signaling in CAL-27 and SCC-4 cells. Conclusions Altogether, our findings identified a crucial role played by ICMT in the progression of TSCC and the potential mechanisms by which exerted its effects, indicating that targeting ICMT may represent a promising therapeutic strategy for TSCC. Availability of data and materials The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

The odor problems in river-type micro-polluted water matrixes are complicated compared to those in lakes and reservoirs. For example, the TY River in Jiangsu Province has been associated with complex odors, whereas the specific odor compounds were not clear. In this paper, a comprehensive study on characterizing the odors and odorants in source water from the TY River was conducted. Six odor types, including earthy, marshy, fishy, woody, medicinal, and chemical odors, were detected for the first time; correspondingly, thirty-three odor-causing compounds were identified. By means of evaluating odor activity values and reconstituting the identified odorants, 95, 93, 92, 90, 89 and 88% of the earthy, marshy, fishy, woody, medicinal and chemical odors in the source waters could be clarified. Geosmin and 2-methylisoborneol were associated with earthy odor, while amyl sulfide, dibutyl sulfide, propyl sulfide, dimethyl disulfide, dimethyl trisulfide and indole were related to marshy odor. The major woody and fishy odor compounds were vanillin, geraniol, β-cyclocitral and 2,4-decadienal, 2-octenal, respectively. Medicinal and chemical odors were mainly caused by 2-chlorophenol, 4-bromophenol, 2,6-dichlorophenol and naphthalene, and 1,4-dichlorobenzene, respectively. This is the first study in which six odor types and thirty-three odorants were identified simultaneously in a river-type micro-polluted water source, which can offer a reference for odor management in drinking water treatment plants.

The odor problems in plain reservoirs are more complex compared to valley reservoirs and ground water reservoirs. Just as YL Reservoir with wetlands ecosystem in Lixiahe Plain, Jiangsu Province has been suffering from complex odors, however, the odorants were unclear. In this study, a systematic study on odorants characterization and evaluation of plain YL reservoir was accomplished. Totally musty, septic, fishy, chemical and grassy odors were first identified simultaneously, twenty-four odorants were identified correspondingly. According to odor activity value ranking, 2-methylisoborneol and geosmin, with odor activity values of 14–18 and 2.5–3.8, were major musty odorants, while bis(2-chloroisopropyl) ether, dimethyl disulfide, dimethyl trisulfide, pentanethiol and indole, with odor activity values of 15.3–18.8, 1–1.3, 1.5–2.3, 2–3 and 0.7-0.9, were major septic compounds. Fishy and grassy odors were associated with 2,4-decadienal, hexanal, nonanal, decanal, benzaldehyde and β-cyclocitral, while chemical odor was related to indane, eucalyptol, 2-nitrophenol, 2-methylphenol, tetramethylpyrazine, 1,4-dichlorobenzene, p-xylene and ethylbenzene. By reconstituting tests, 98, 95, 88, 85 and 81 % of musty, septic, fishy, chemical and grassy characteristics in source water could be explained. It was notable that wetlands ecosystem has almost no effect on odor removal. This study would offer more understandings and supports for odors's control in such source waters.

The relationship between mechanical force and alveolar bone remodeling is an important issue in orthodontics because tooth movement is dependent on the response of bone tissue to the mechanical force induced by the appliances used. Mechanical cyclical stretch plays an essential role in the cell osteogenic differentiation involved in bone remodeling. However, the underlying mechanisms are unclear, particularly the molecular pathways regulated by mechanical stimulation. In the present study, we reported a dynamic change of p21 level in response to mechanical cyclical stretch, and shRNA-p21 in bone marrow mesenchymal stem cells (BMSCs) induced osteogenic differentiation. The mechanism was mediated through TWIST/E2A/p21 axis. These results supported the mechanical stimulation-induced osteogenic differentiation is negatively regulated by p21.

Dwarf bunt of wheat caused by Tilletia controversa Kuhn has been identified an international quarantine disease, which replace the grain material into millions of teliospores. Agrobacterium tumefaciens-mediated transformation (ATMT) system is a powerful tool for fungi transformation with significant advantages of simple operation, high efficiency, and genetic stability of transformants. In this study, we constructed ATMT system for T. controversa. All the transformants were tested using Acetosyringone (AS) concentration at 150 μmol/l, hygromycin B at 25 μg/ml, 1 × 106 T. controversa hypha cells/ml, A. tumefaciens with OD600 of 0.5 co-cultivation at 16 °C for 48 h and culture was incubated at 16 °C for 20 days. Using the ATMT method, we cultivated 8 generations of transformants on complete medium (CM) containing hygromycin B antibiotic and validated by PCR, which indicate that T-DNA had been successfully inserted into each of T. controversa transformants. In addition, thermal asymmetric interlaced PCR (TAIL-PCR) evaluated the Ti element inserts were at random sites in the fungal genome. Thus, ATMT approach is an efficient tool for insertional mutagenesis of T. controversa.

The coupling between constructed wetlands and reservoir (CWs-R) afforded a novel ecosystem to improve the water quality and increase the emergency storage capacity of micro-polluted river drinking water source. In this study, spectroscopic characteristics of DOM in YL CWs-R ecosystem were first systematic studied based on a three-year field monitoring to investigate the chemical composition, sources and track the involved biogeochemical processes in the ecosystem. Three humic-like components (C1, C2, and C4, em >380 nm) and one protein-like component (C3, em 0.05), which implies that the biodegradation and production of protein-like component may balance each other in the CWs-R ecosystem. The ecological pond unit plays a major role in the removal and transformation of DOM, especially in summer, while wetland purification unit contributes little to DOM reduction. In addition, the decay of aquatic macrophytes in wetland purification unit and the risk of algal bloom in the ecological pond unit might become important autochthonous sources of DOM, especially in summer and autumn. These findings are critical for further understanding the transformation processes of DOM in large-scale CWs-R ecosystems, and could provide important implications to improve sustainable safety of drinking water sources.

Ozone and biological activated carbon (BAC) are known to be effective at removing odors in drinking water. However, the specific variations in complex odors and odorants along the course of advanced treatments in full-scale drinking water treatment plants (DWTP) have remained unclear. In this paper, the migration of odors and odorants through pre-ozonation, sedimentation, post-ozonation, and BAC treatment processes were studied from January to December 2019 in a DWTP. The results indicated that septic, musty, and chemical odors with intensities of 6-6.7, 6-7.5, 4-5 could be removed by both ozonation and BAC, while grassy, fishy odors with intensities of 3.3-4.8, 2.3-5.8 could not be removed until the BAC step. Twenty-four odorants identified in raw water were classified as musty (2-methylisoborneol, geosmin), chemical (e.g. indane, eucalyptol), septic (e.g. dimethyl disulfide, pentanethiol), fishy (2,4-decadienal) and grassy (nonanal, decanal) odor compounds. It is noteworthy that eleven additional odorants were produced after ozonation; in addition, the concentrations of fishy and grassy odorants were increased after ozonation, and the concentrations of musty, septic, fishy, and grassy odorants were increased after sedimentation, suggesting that sedimentation and ozonation should be carefully managed. BAC was the most effective at removing the above odorants simultaneously. This study would be helpful for providing more insights into the migration of odorants along treatment processes and understanding the mitigation of odors in DWTPs using raw waters with complex odors.

Smoking is identified as a risk factor for periodontitis. Carbon monoxide (CO)-releasing molecule-3 (CORM-3) is a compound that has demonstrated anti-inflammatory effects in vitro and in vivo studies. The present study aimed to investigate the effects of CORM-3 on the expression of inflammatory and osteoclastogenic cytokines in human periodontal ligament cells (PDLCs) stimulated by nicotine and lipopolysaccharide (LPS). The cells were pretreated with CORM-3 and then cultured in medium in the presence of nicotine and LPS. The mRNA and protein expression levels of prostaglandin E2 (PGE2), cyclooxygenase-2 (COX‑2), osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL) and heme oxygenase-1 (HO-1) were evaluated using reverse transcription-quantitative polymerase chain reaction and western blot analysis. The mRNA and protein expression levels of these cytokines were also evaluated in PDLCs transiently transfected with HO-1 small interfering RNA (siRNA) in response to nicotine and LPS stimulation. CORM-3 attenuated the LPS- and nicotine-induced production of PGE2, COX-2 and RANKL in human PDLCs by releasing CO, and upregulated the expression of OPG. However, these effects of CORM-3 were abrogated when HO-1 siRNA was transiently transfected into the cells. These results demonstrate that CORM-3 exerts anti-inflammatory and anti-osteoclastogenic effects on nicotine- and LPS-stimulated human PDLCs via the HO-1 pathway, which suggests its promising potential for use in the treatment of inflammatory periodontal disease.

Despite the strong oxidizing ability of ozone, pre-ozonation has seldom been employed for the purpose of micropollutant removal in drinking water utilities. In this paper, the possibility of using pre-ozonation instead of post-ozonation for the removal of micropollutants was explored because of the lower risk of forming carcinogenic bromate. A 1.0 m3/h pilot system was utilized to compare the efficacy of pre- and post-ozonation in the removal of bulk organic pollutants as well as micropollutants, including typical odor-causing compounds, pharmaceuticals, and typical pesticides, from one source water (Huangpu River) characterized by the occurrence of various micropollutants. Both pre-ozonation and post-ozonation could achieve similar water purification performance under an ozone dose of 1.5 mg/L, in terms of bulk water quality parameters like CODMn (66% in combination with biological activated carbon (BAC) treatment, compared to 62% with the pre-ozonation-BAC combination) or micropollutants including 27 pharmaceuticals (85% in combination with BAC compared to 87% with the pre-ozonation-BAC combination) and 25 pesticides (72% in combination with BAC compared to 61% with the pre-ozonation-BAC combination). Pre-ozonation exhibited slightly better odorant removal performance (100% in combination with BAC compared to 92% with the post-ozonation-BAC combination); however, post-ozonation generated approximately 6.0 μg/L bromate at an ozone dose of 2.0 mg/L, while pre-ozonation did not form bromate even at an ozone dose as high as 3.0 mg/L. So pre-ozonation in combination with BAC might be a solution for the removal of micropollutants from source water with high bromate formation risk. The results of this study will be helpful for the optimization of ozonation processes in the water supply industry.

Comparing with the normal mechanical inertial stabilized platform (ISP), the novel ISP with magnetic bearing to suspend the yaw gimbal owns the ability of isolating the vibration and disturbance of external gimbal. However, on the one hand, complex structure of the magnetically suspended gimbal introduces parametric uncertainties into modeling of magnetic suspension force, and the disturbance of magnetic fields brings the unmodeled force into dynamics of magnetically suspended gimbal. On the other hand, external disturbances such as wind drag affect the stability of magnetically suspended gimbal. Therefore, H∞robust controllers for translation and tilting of gimbal are designed to dampen the negative influence on stability and improve the robustness of system. The experimental results indicate that the robust controller of magnetically suspended gimbal owns the excellent robustness when the load of magnetically suspended gimbal changes.

In a magnetically suspended inertially stabilized platform, the yaw gimbal is suspended by the magnetic bearing, which can effectively isolate the external vibrations and disturbances. However, coupling torques and disturbance torques among gimbals still exist. Therefore, based on the cross feedback compensation, the output angles of gimbals are introduced as feedback variables, and the inverse coordinate transformation matrix is designed to compensate for the coupling torques. Furthermore, a disturbance observer is applied to inhibit the disturbance torque and simulations indicate that the disturbance observer can accurately estimate the disturbance torque. Consequently, the experimental results demonstrate that the cross feedback compensation can inhabit the coupling torques, and the disturbance observer greatly suppresses the external disturbance torques and improves the angular displacement precision of gimbals.

Swampy/septic odors are one of the most important odor types in drinking water. However, few studies have specifically focused on it compared to the extensive reported musty/earthy odor problems, even though the former is much more offensive. In this study, an investigation covering the odor characteristics, algal distribution and possible odorants contributing to swampy/septic odor, including dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), diisopropyl sulfide (DIPS), dipropyl sulfide (DPS), dibutyl sulfide (DBS), 2-methylisoborneol (2-MIB) and geosmin (GSM), was performed in source and finished water of 56 drinking water treatment plants (DWTPs) in 31 cities across China. While the musty/earthy and swampy/septic odors were dominant odor descriptors, the river source water exhibited a higher proportion of swampy/septic odor (38.5%) compared to much higher detection rate of musty/earthy odor (50.0%) in the lake/reservoir source water. The occurrence of swampy/septic odor, which was much easier to remove by conventional drinking water treatment processes compared to musty/earthy odors, was decreased by 62.9% and 46.3% in river and lake/reservoir source water respectively. Statistical analysis showed that thioethers might be responsible for the swampy/septic odor in source water (R2 = 0.75, p

The electrostatic suspension system is a contactless detective method to analyze the material properties of test sample. In this article, the characteristics about electric field force and electric image force of an electrostatic suspension system are analyzed, and the force analysis and dynamic functions of test sample in the electrostatic suspension system are developed. The suspension precision of test sample in vertical direction is sensitive to the gravity and the disturbances. Therefore, an active disturbance rejection control (ADRC) model including a displacement control loop and an acceleration control loop is designed to the suspension control of test sample. The simulation and experiment are conducted to validate the effectiveness of ADRC model when the random and impulse disturbances are imposed on the test sample in vertical direction, and results indicate that the ADRC model could improve the robust stability of test sample and reduce the oscillation amplitude of high voltage electrodes.

The presence of earthy-musty odors in drinking water is a major concern for water suppliers and consumers worldwide. While geosmin and 2-methylisoborneol are the most studied earthy-musty odor-causing compounds, pyrazine and its alkyl and methoxy compounds possess similar odors and are widely distributed in nature, foods, and beverages. In this study, odor characteristics of pyrazines and their presence in natural and treated waters were determined. Pyrazine, 2,6-dimethyl-pyrazine (DMP), 2,3,5-trimethyl-pyrazine (TrMP), 2-ethyl-5(6)-methyl-pyrazine (EMP), 2,3,5,6-tetramethyl-pyrazine (TeMP), 2-isobutyl-3-methoxy-pyrazine (IBMP) and 2-isopropyl-3-methoxy-pyrazine (IPMP) were measured in source and finished drinking water across China. 2-Methoxy-3,5-dimethyl-pyrazine (MDMP), IBMP, and IPMP were investigated in rivers in Virginia, USA. The results showed that “musty” and “sweet” were the most common descriptors for pyrazine, DMP, MDMP, TrMP, and TeMP. While IBMP and IPMP were never detected in 140 source or drinking water samples from across China, pyrazine, DMP, MDMP, TrMP, and TeMP occurred throughout with concentrations of n.d.−62.2 ng/L-aq in source water and n.d.−39.6 ng/L-aq in finished water. IBMP, IPMP, and MDMP were present in two Virginia rivers; MDMP occurred in 18% of the samples with concentrations of n.d.−4.4 ng/L, many of which were above the aqueous odor threshold of 0.043 ng/L MDMP. The removal efficiencies through conventional water treatment were poor, ranging from negative removals to ∼10%. Advanced oxidation water treatment could only remove EMP and TrMP. The widespread presence of earthy-musty-sweet pyrazines in source and drinking waters on two continents, their poor removal during water treatment, and ng/L odor threshold concentrations confirm their potential to be T&O issues for consumers.

Unpleasant odor in drinking water is a worldwide substantial issue for consumers and water utilities. However, its hidden social impact has been ignored as there are no apparent direct health effects compared with other pollutants. In this study, we developed a method to characterize the adverse effects of a typical odorant based on behavioral responses with the corresponding economic burden, illustrated by 2-methylisoborneol (2-MIB). The dose-response based on behavioral responses to odors using a questionnaire was established in consideration of the bandwagon effect. Results showed that about half of consumers adopted averting behaviors after detecting even very weak odor (but generally recognizable) in drinking water. Total economic burden was determined to be 290690 ± 27427 ¥ per million people per day by the surcharges arising from consumer averting behavior or additional treatment of drinking water odor, among which about 13% of surcharge originated from insensitive people because of bandwagon effect. This is the first study to quantify odor hidden risk based on people’s behavioral responses using economic burden, which provides a useful tool to comparing the risks of different types of pollutants in drinking water.

Many cities are located in lands with typical basin topographies, which are not conducive to the spread of air pollutants. In the winter of 2016/2017, a severe haze happened in Xi’an, the main city in the Guanzhong Basin in central China. When the peak daily concentration of fine particulate matter (PM2.5) reaches 499 μg/m3, the source of the atmospheric pollution needs to be found urgently in order to take countermeasures. The comprehensive air quality model with extensions, coupled with the tracer tagging particulate source apportionment technology (PSAT) module, and an improved emission inventory, higher grid resolution, and bigger inner domain area, have been applied to quantify the contributions of local and regional emissions to the PM2.5 pollutions. The model performed well in time period considered in this study. The correlation of the simulated daily PM2.5 concentration data reaches 0.82, and the fraction of predictions within a factor of two of observations approaches 84%. With the PSAT module, the PM2.5 contributions from local and regional sources to the urban centre and rural areas during the severe winter haze event are analysed in detail. The PM2.5 concentrations in the urban centre in Xi’an is mainly originating from local emissions (60%), and Xianyang City is the largest contributor among the surrounding source regions (11.6%), while the transportation sector outside the Shaanxi Province (5.1%) also contributes significantly. Comparatively, the rural areas have lower local contributions and higher transport contributions. In particular, in the northern rural area Yanliang, the contribution from surrounding source regions approaches 82%. The results of this study suggest that to improve the air quality in a typical basin city, a regional-scale coordinated emissions control should be used, focusing on the emissions from both local and surrounding areas.

Water soluble protein content (WSPC) is a parameter of great significance to the soybean food industry. So far, genetic studies and breeding practices have been limited by the lack of a rapid technique for the evaluation of WSPC. Near-infrared reflectance spectroscopy (NIRS) is widely applied for rapid quantification of many traits, including moisture, protein and oil content, and dietary fiber. The present study aimed to establish and evaluate a NIRS regression model for the rapid prediction of WSPC in soybean. Results showed that seed coat color had a profound impact on the accuracy of protein content prediction, whereas the seed coat itself deeply influenced protein determination. We established a partial least squares (PLS) regression model with 167 soybean samples whose seed coat had been removed. Based on multiplicative scatter correction and Savitsky-Golay transformation, the highest determination coefficient (R2) was 0.831, and the relative predictive determinant was 2.417. Further analysis showed that seed roundness correlated negatively with WSPC (r=-0.59, P

A wide range of compounds with various structural features can cause taste and odor (T&O) problems in drinking water. It would be desirable to determine all of these compounds using a simple analytical method. In this paper, a sensitive method combining liquid–liquid extraction (LLE) with gas chromatography-triple quadrupole tandem mass spectrometry (GC–MS/MS) was established to simultaneously analyze 51 odor-causing compounds in drinking water, including organic sulfides, aldehydes, benzenes, phenols, ethers, esters, ketones, nitrogenous heterocyclic compounds, 2-methylisoborneol and geosmin. Three deuterated analogs of target analytes, dimethyl disulfide-d6, benzaldehyde-d6 and o-cresol-3,4,5,6-d4, were used to correct the variations in recovery, and five isotope-labeled internal standards (4-chlorotoluene-d4, 1, 4-dichlorobenzene-d4, naphthalene-d8, acenaphthene-d10, phenanthrene-d10 respectively) were used prior to analysis to correct the variations arising from instrument fluctuations and injection errors. The calibration curves of the target compounds showed good linearity (R2 > 0.99, level = 7), and method detection limits (MDLs) below 1/10 of the odor threshold concentrations were achieved for most of the odorants (0.10–20.55 ng/L). The average recoveries of most of the analytes in tap water samples were between 70% and 120%, and the method was reproducible (RSD

Botryosphaeria kuwatsukai is an important fungal pathogen affecting pear fruits. However, infection processes of this fungus are still unclear. This study seeks to develop the fungal transformation of B. kuwatsukai by Agrobacterium tumefaciens-mediated transformation (ATMT), assess the reliability of appropriate vectors and examine the infection processes in vitro using a GFP labeled strain of B. kuwatsukai. To establish a highly effective transformation system in B. kuwatsukai, binary vectors containing various lengths of H3 promoters and TEF promoters fused with GFP and hygromycin B resistance gene cassettes were constructed. These cassettes were integrated into the genomic DNA of B. kuwatsukai with high transformation frequency by the ATMT method. Transformants showed strong expression of GFP and hygromycin B resistance genes in cells. Furthermore, we investigated if native promoters are more suitable to govern marker genes than other general promoters used in other filamentous fungi. The results obtained herein demonstrate that the vectors constructed in this study can be utilized with high transformation rate. Microscopic examinations also reveal that fungal hyphae undergo morphological changes during the infection process resulting in biotrophic stage of infected host cells. Our results provide genetic insights to further explore the infection processes of B. kuwatsukai.

Odor problems in drinking water, particularly swampy/septic odors, are normally triggered by a set of organic compounds with odor threshold concentrations (OTC) ranging from ng L−1 to μg L−1. With such a low level of OTC, it has long been a challenge to effectively determine the odor-causing compounds in highly complex samples. The Huangpu and Huai rivers, as source waters in south China, have exhibited continuous swampy/septic odor over the entire year, yet the corresponding odor-causing compounds remain unclear. In order to screen the odor-causing compounds in these two rivers, a method to simultaneously determine fifty-four frequently encountered compounds with categories of thioethers, aldehydes, pyrazines, benzenes and phenols, has been developed using comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC × GC-TOFMS) based on liquid–liquid extraction. The results indicated that this method could allow the analysis of different categories of compounds without derivatization at considerably higher sensitivities. Four thioether compounds, including dimethyl disulfide, diethyl disulfide, propyl sulfide, and amyl sulfide, and one ether compound (bis(2-chloroisopropyl) ether) were at least detected in one of the source waters with a concentration higher than their OTC value, suggesting that these compounds might be the main compounds causing the swampy/septic odor. At the same time, other compounds, including pyrazine, pyridine, 2-methyl-phenol, 2-nitro-phenol, and 2,6-dimethyl-phenol, were detected with a concentration lower than their respective OTC value. The contribution of these compounds to the swampy/septic odor requires further evaluation.

The typical musty/earthy odor-causing compound, 2-methylisoborneol (MIB), is usually associated with the occurrence and proliferation of benthic/subsurface-living cyanobacteria in source water. Control of MIB-producing cyanobacteria in source water may greatly reduce the processing burden for drinking water treatment plants. We explored the mechanism and feasibility of restricting the growth of subsurface-living Planktothrix sp. by reducing underwater light availability. The effects of light intensity (5, 17, 36, 85, and 250 μmol photons m−2 s−1) on the growth and MIB production of Planktothrix sp. were first determined using batch culture, followed by an in-situ experiment deployed at different depths (0.5, 1.5, 3.5, and 5.0 m) in a drinking source water reservoir (Miyun Reservoir, China) to verify the laboratory results. The optimum conditions for growth (7.5 × 108 cells L−1) and MIB production ((1300 ± 29) μg L−1) of Planktothrix sp. were achieved at 85 μmol photons m−2 s−1 in the laboratory and at 1.5 m (the corresponding average light intensity of 66 μmol photons m−2 s−1) in the field. The minimum light requirement for the growth of Planktothrix sp. (4.4 μmol photons m−2 s−1) was determined according to the laboratory data. While the in-situ experiment further indicated that Planktothrix sp. could not successfully grow at depths of 5 m where light intensity was below the minimum light requirement. In addition, the history data also verified the negative relationships between underwater light availability and MIB concentration.

Ozonation is known to be very effective in the removal of odorants from source water. However, it is not known if ozonation is effective in the removal of multiple odorants causing different types of odors. In this study, the removal performance for odors and odorants were evaluated in a Water Treatment Plant (WTP), which was equipped with coagulation, sedimentation, ozonation, biological activated carbon (BAC) filtration, sand filtration, and chlorination in succession and located in the downstream of the Huangpu (HP) River, over the period from April, 2014 to April, 2015. Flavor profile analysis (FPA) results showed that the source water was constantly associated with septic and musty odors. Geosmin and 2-MIB, with an average OAV of 4.54 and 1.38, respectively, were the major odorants for musty odor, while bis(2-chloroisopropyl) ether, DEDS and DMDS with an average OAV of 2.35, 1.65 and 0.78, respectively, might be responsible for the septic odor. While the musty odor could be removed effectively through the combination of ozonation and BAC, the septic odor and associated odorants required further treatment with sand filtration and chlorination for complete removal. It is clear that the advanced treatment process was effective for the treatment of source water containing complicated odorants. It should be noted that the sedimentation process needs careful management because release of odorants may occur during the treatment. The result of this study will be helpful for the mitigation of odors in WTP using source waters suffering from complicated odor problems.