Re-evaluation and modification of dehydrogenase activity tests in assessing microbial activity for wastewater treatment plant operation.

Reliable and cost-effective methods for monitoring microbial activity are critical for process control in wastewater treatment plants. The dehydrogenase activity (DHA) test has been recognized as an efficient measure of biological activity due to its simplicity and broad applicability. Nevertheless, the existing DHA test methods suffer from imperfections and are difficult to implement as routine monitoring techniques. In this work, an accurate and cost-effective modified DHA approach was developed and the procedure for the DHA test was critically evaluated with respect to the standard construction, sample pretreatment, incubation and extraction conditions. The feasibility of the modified DHA test was demonstrated by comparison with the oxygen uptake rate and adenosine triphosphate in a sequencing batch reactor. The sensitivities of the two typical tetrazolium salts to toxicant inhibition by heavy metals and antibiotics were compared, revealing that 2,3,5-triphenyltetrazolium chloride (TTC) exhibited a higher sensitivity. Furthermore, the sensitivity mechanism of the two DHA tests was elucidated through electrochemical experiments, theoretical analysis and molecular simulations. Both tetrazolium salts were found to be effective artificial electron acceptors due to their low redox potentials. Molecular docking simulations revealed that TTC could outperform other tetrazolium salts in accepting electrons and hydrogens from dehydrogenase. Overall, the modified DHA approach presents an accurate and cost-effective way to measure microbial activity, making it a practical tool for wastewater treatment plants.

Carrier-Free Binary Self-Assembled Nanomedicines Originated from Traditional Herb Medicine with Multifunction to Accelerate MRSA-Infected Wound Healing by Antibacterial, Anti-Inflammation and Promoting Angiogenesis.

Background: Deaths from bacterial infections have risen year by year. This trend is further aggravated as the overuse antibiotics and the bacterial resistance to all known antibacterial agents. Therefore, new therapeutic alternatives are urgently needed. Methods: Enlightenment the combination usage of traditional herb medicine, one carrier-free binary nanoparticles (GA-BBR NPs) was discovered, which was self-assembled from gallic acid and berberine through electrostatic interaction, π-π stacking and hydrophobic interaction; and it could be successfully prepared by a green, cost-effective and "one-pot" preparation process. Results: The nanoparticles exhibited strong antibacterial activity and biofilm removal ability against multidrug-resistant S. aureus (MRSA) by downregulating mRNA expression of rpsF, rplC, rplN, rplX, rpsC, rpmC and rpsH to block bacterial translation mechanisms in vitro and in vivo, and it had well anti-inflammatory activity and a promising role in promoting angiogenesis to accelerate the wound healing on MRSA-infected wounds model in vivo. Additionally, the nanoparticles displayed well biocompatibility without cytotoxicity, hemolytic activity, and tissue or organ toxicity. Conclusion: GA-BBR NPs originated from the drug combination has potential clinical transformation value, and this study provides a new idea for the design of carrier-free nanomedicine derived from natural herbals.

A metal ions-mediated natural small molecules carrier-free injectable hydrogel achieving laser-mediated photo-Fenton-like anticancer therapy by synergy apoptosis/cuproptosis/anti-inflammation.

Tumor microenvironment (TME) plays an important role in the tumorigenesis, proliferation, invasion and metastasis. Thereby developing synergistic anticancer strategies with multiple mechanisms are urgent. Copper is widely used in the treatment of tumor chemodynamic therapy (CDT) due to its excellent laser-mediated photo-Fenton-like reaction. Additionally, copper can induce cell death through cuproptosis, which is a new modality different from the known death mechanisms and has great promise in tumor treatment. Herein, we report a natural small molecules carrier-free injectable hydrogel (NCTD Gel) consisted of Cu2+-mediated self-assembled glycyrrhizic acid (GA) and norcantharidin (NCTD), which are mainly governed by coordination and hydrogen bonds. Under 808 nm laser irradiation, NCTD Gel can produce reactive oxygen species (ROS), consume glutathione (GSH) and overcome hypoxia in TME, leading to synergistically regulate TME via apoptosis, cuproptosis and anti-inflammation. In addition, NCTD Gel's CDT display high selectivity and good biocompatibility as it relies on the weak acidity and H2O2 overexpression of TME. Notably, NCTD Gel's components are originated from clinical agents and its preparation process is easy, green and economical, without any excipients. This study provides a new carrier-free hydrogel synergistic antitumor strategy, which has a good prospect in industrial production and clinical transformation.

Discovery, traceability, formation mechanism, metal and organic components analysis of supramolecules from Maxing Shigan decoction.

Traditional Chinese medicine (TCM) decoction is a complex polydispersed phase system containing colloid solution, emulsion and suspension, which maybe induced by the supramolecular phenomenon in decoction. However, until now there is no systematic analysis of composition and formation mechanism of supramolecules in TCM decoction contained mineral drug and herb medicines. Maxing Shigan Decoction (MXSGT), one of the classic TCM recipes, has been widely used in the treatment of fever in clinic. In this study, we obtained the supramolecular part of MXSGT (MXSGT NPs). And its traceability, formation mechanism, metal and organic components were further analyzed. The morphology was characterized by scanning electron microscopy (SEM) and dynamic light scattering (DLS); and the lipopolysaccharides (LPS) induced rats' fever model was established to evaluate the antipyretic effect of MXSGT NPs. Furthermore, interaction of the disassembled groups was studied to explore the traceability and formation mechanism of MXSGT NPs by isothermal titration calorimeter (ITC). Due to the combination of mineral gypsum and herb medicines, both ICP-OES and UHPLC-Q-Orbitrap HRMS were used to analyze metal and organic components of MXSGT and MXSGT NPs, respectively. The results showed that MXSGT NPs was regular spherical nanoparticles and had the same antipyretic effect as MXSGT. Moreover, MXSGT NPs was formed by the interaction between metal and organic components, resulted in enriching the main active compounds of MXSGT. This study would provide a new idea of studying TCM decoction, especially clarifying the connotation with the participation of mineral gypsum.

Integrative multi-omics unravels the amelioration effects of Zanthoxylum bungeanum Maxim. on non-alcoholic fatty liver disease.

BACKGROUND: The effect of Zanthoxylum bungeanum Maxim. (ZBM) on anti-obesity, lipid-lowering and liver protection has been identified, but the effect on the development of NAFLD induced by high-fat diet remains unclear. PURPOSE: To evaluate the alleviation effect of ZBM on NAFLD in vivo and explore the mechanisms by analyzing the liver transcriptome, microbiota and fecal metabolites. METHODS: NAFLD model was induced in C57BL/6J mice by feeding with high-fat diet (HFD). The potential mechanism of ZBM in improving NAFLD was studied by liver transcriptome analysis, real-time PCR, immunofluorescence, 16s rRNA sequencing and non-targeted metabonomics. RESULTS: ZBM has alleviation effects on HFD-induced NAFLD. The liver transcriptome, real-time PCR and immunofluorescence analysis showed that ZBM could efficiently regulate fatty acid and cholesterol metabolism. The 16S rRNA sequencing and LC-MS based metabonomic demonstrated that ZBM could rebalance gut microbiota dysbiosis and regulate metabolic profiles in HFD-induced NAFLD mice. Spearman correlation analysis revealed a strong correlation between gut microbiota and biochemical, pathological indexes and differential metabolic biomarkers. CONCLUSION: ZBM ameliorates HFD-induced NAFLD by regulating fatty acid and cholesterol metabolism, gut microbiota and metabolic profile.

Natural Carrier-Free Binary Small Molecule Self-Assembled Hydrogel Synergize Antibacterial Effects and Promote Wound Healing by Inhibiting Virulence Factors and Alleviating the Inflammatory Response.

Methicillin-resistant Staphylococcus aureus (MRSA)-infected skin wounds have caused a variety of diseases and seriously endanger global public health. Therefore, multidimensional strategies are urgently to find antibacterial dressings to combat bacterial infections. Antibacterial hydrogels are considered potential wound dressing, while their clinical translation is limited due to the unpredictable risks and high costs of carrier excipients. it is found that the natural star antibacterial and anti-inflammatory phytochemicals baicalin (BA) and sanguinarine (SAN) can directly self-assemble through non-covalent bonds such as electrostatic attraction, π-π stacking, and hydrogen bonding to form carrier-free binary small molecule hydrogel. In addition, BA-SAN gel exhibited a synergistic inhibitory effect on MRSA. And its plasticity and injectability allowed it to be applied as a wound dressing. Due to the matched physicochemical properties and synergistic therapeutic effects, BA-SAN gel can inhibit bacterial virulence factors, alleviate wound inflammation, promote wound healing, and has good biocompatibility. The current study not only provided an antibacterial hydrogel with clinical value but also opened up new prospects that carrier-free hydrogels can be designed and originated from clinically used small-molecule phytochemicals.

Revealing the active ingredients of the traditional Chinese medicine decoction by the supramolecular strategies and multitechnologies.

ETHNOPHARMACOLOGICAL RELEVANCE: Glycyrrhiza uralensis Fisch (RC) and Coptis chinensis Franch (RG) are traditional Chinese medicines, which are classic drug pair in prescriptions to treat gastrointestinal diseases. Multi-herb therapy is one of the most important features of traditional Chinese medicine, but due to the complex components of herbal decoctions, the substances that actually exert their medicinal effects have not been fully elucidated. The discovery of Glycyrrhiza uralensis Fisch and Coptis chinensis Franch supramolecular parts (RC-RG SA) can provide a new perspective for explaining the mechanism of drug-pair compatibility. AIM OF THE STUDY: The purpose of this study was to explore the active composition and identification of chemical constituents of RC-RG SA, and to explore the inhibitory effects of supramolecular parts on S. aureus and biofilm. MATERIALS AND METHODS: The micromorphology of RC-RG SA was characterized by SEM and DLS. Intermolecular forces between Glycyrrhiza uralensis Fisch and Coptis chinensis Franch determined by ITC. The chemical constituents of RC-RG SA were systematically analyzed by UPLC-ESI-MSn. The inhibitory effect of RC-RG SA on S. aureus was determined by turbidimetric method and plate coating method. The scavenging effect of RC-RG SA supramolecular parts on S. aureus biofilm were observed by MTT method, SEM and LSCM, respectively. RESULTS: The microstructure of RC-RG SA was spherical with a particle size of 161.6 nm. ITC proved that the reaction between decoction of RC and RG was exothermic. A total of 70 compounds were preliminarily identified in RC-RG SA, including 34 flavonoids, 34 alkaloids and 2 triterpenoids. The inhibitory effect of RC-RG supramolecular parts on S. aureus proliferation and the ability to clear S. aureus biofilm were better than RC-RG co-decoction and RC-RG non-supramolecular parts. CONCLUSIONS: The Glycyrrhiza uralensis Fisch and Coptis chinensis Franch co-decoctions' supramolecular components were an important substance that exerts its medicinal effect. Current study provided supramolecular strategies to reveal the active ingredients and the medicinal effect of the traditional Chinese medicine decoction.

Thermodynamics driving phytochemical self-assembly morphological change and efficacy enhancement originated from single and co-decoction of traditional chinese medicine.

Through the self-assembled strategy to improve the clinical efficacy of the existing drugs is the focus of current research. Herbal formula granule is a kind of modern dosage form of traditional Chinese medicine (TCM) which has sprung up in recent decades. However, whether it is equivalent to the TCM decoction that has been used for thousands of years has always been a controversial issue. In this paper, taking the herb pair of Coptidis Rhizoma-Scutellariae Radix and its main component berberine-baicalin as examples, the differences and mechanisms of self-assemblies originated from the co-decoction and physical mixture were studied, respectively. Moreover, the relationship between the morphology and antibacterial effects of self-assemblies was illuminated via multi-technology. Our study revealed that the physical mixture's morphology of both the herb pair and the phytochemicals was nanofibers (NFs), while their co-decoction's morphology was nanospheres (NPs). We also found that the antibacterial activity was enhanced with the change of self-assemblies' morphology after the driving by thermal energy. This might be attributed to that NPs could influence amino acid biosynthesis and metabolism in bacteria. Current study provides a basis that co-decoction maybe beneficial to enhance activity and reasonable use of herbal formula granule in clinic.

Natural Small-Molecule-Based Carrier-Free Self-Assembly Library Originated from Traditional Chinese Herbal Medicine.

The carrier-free self-assembly of small molecules opens a new window for the development of nanomaterials. This study is dedicated to developing binary small-molecular self-assemblies derived from phytochemicals in traditional Chinese herbal medicine. Among them, Rhei Radix et Rhizoma and Coptidis Rhizoma are a common pair used in clinics for thousands of years. Here, we found that there were numerous spherical supramolecular nanoparticles (NPs) originated from Rhei Radix et Rhizoma and Coptidis Rhizoma decoction. Ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) was used to analyze the composition of the supramolecules, and a total of 119 phytochemicals were identified (23 anthraquinones, 31 alkaloids, 24 organic acids, 8 tannins, and other components). Isothermal titration calorimetry (ITC) showed that the interaction between Rhei Radix et Rhizoma and Coptidis Rhizoma was a spontaneous exothermic reaction, indicating that their phytochemicals had the property of self-assembly and interacted to form supramolecules in the decocting process. Furthermore, scanning electron microscopy (SEM), UV, IR, NMR, and ITC were used to verify that rhein and coptisine could self-assemble into nanofibers (Rhe-Cop NFs), while emodin and coptisine could self-assemble into nanoparticles (Emo-Cop NPs). The formation mechanism analysis of the self-assemblies revealed that they were induced by electrostatic attraction, hydrogen bonding, and π-π stacking, forming nanospheres of about 50 nm and nanofibers. The current study not only provides an idea of discovering carrier-free self-assemblies from traditional herbal medicine decoction but also supplies a reference for the design of binary self-assembly of small molecules in the future.

Injectable Carrier-Free Hydrogel Dressing with Anti-Multidrug-Resistant Staphylococcus aureus and Anti-Inflammatory Capabilities for Accelerated Wound Healing.

Antibacterial hydrogels have gradually become a powerful weapon to treat bacterially infected wounds and accelerate healing. In this paper, we designed a small-molecule self-healing antibacterial hydrogel containing 100% drug-loaded benzyl 3ß-amino-11-oxo-olean-12-en-30-oate (GN-Bn), which was governed by π-π stacking, hydrogen bonding, and van der Waals forces. Due to the carrier-free design concept, the problems of interbatch variability during sample preparation and carrier-related toxicity can be effectively avoided. Moreover, the GN-Bn hydrogel exhibited promising antibacterial activities against multidrug-resistant Staphylococcus aureus (MRSA). The minimum inhibitory concentration (MIC) of the GN-Bn hydrogel was 1.5625 nmol/mL, which was lower than those against clinical agents such as norfloxacin, penicillin, and tetracycline. This is attributed to its unique antibacterial mechanism that aims at killing bacteria or preventing their growth by regulating arginine biosynthesis and metabolism through both transcriptomic (RNA-seq) analysis and quantitative polymerase chain reaction (qPCR) analysis. In addition, the GN-Bn hydrogel can also inhibit proinflammatory cytokines (TNF-α, IL-1ß, and IL-6) to promote wound healing. Collectively, the GN-Bn hydrogel elicited dual therapeutic effects on an MRSA-infected full-thickness skin wound model through its antibacterial and anti-inflammatory activities, which is attributed to the fact that the GN-Bn hydrogel has multiple advantages including sufficient mechanical stability, biocompatibility, and unique antibacterial mechanisms, making it significantly accelerate MRSA-infected full-thickness skin wound healing as a wound dressing. In a word, the GN-Bn antibacterial hydrogel dressing with an anti-inflammatory and antibacterial bifunctional material holds great potential in clinical application.

Multi-functional self-assembly nanoparticles originating from small molecule natural product for oral insulin delivery through modulating tight junctions.

BACKGROUND: Oral administration of insulin (INS) could be absorbed into systemic circulation only if the carrier protected it from the hostile gastrointestinal conditions. However, traditional macromolecular carriers have not totally overcome challenges in addressing these biological barriers. RESULT: In this study, inspired by small molecule natural products (SMNPs), we demonstrate the multi-functional self-assembly nanoparticles (BA-Al NPs) originating from baicalin (BA) and AlCl3 through coordination bonds and hydrogen bonds. As a novel carrier for oral insulin delivery (INS@BA-Al NPs), it displayed effective capacity in pH stimuli-responsive insulin release, intestinal mucoadhesion and transepithelial absorption enhance. Meanwhile, BA improved the paracellular permeability for insulin absorption, because of its downregulation at both mRNA and protein level on internal tight junction proteins. In vivo experiments exhibited remarkable bioavailability of INS and an ideal glucose homeostasis in the type I diabetic rat model. CONCLUSION: This study offers a novel frontier of multi-functional carriers based on SMNPs with self-assembly character and bioactivity, which could be a promising strategy for diabetes therapy.

Revealing the Toxicity-Enhancing Essence of Glycyrrhiza on Genkwa Flos Based on Ultra-high-performance Liquid Chromatography Coupled With Quadrupole-Orbitrap High-Resolution Mass Spectrometry and Self-Assembled Supramolecular Technology.

Researchers often focus on the mechanisms of synergistic agents, a few explore drug combinations that enhance toxicity, while few have studied the internal mechanism of compatibility enhancement in chemical level. Herein, we present a comprehensive analysis based on ultra-high-performance liquid chromatography coupled with quadrupole-Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) and a self-assembled supramolecular strategy, which reveals the toxicity-enhancing essence of glycyrrhizic acid originated in licorice when combined with Genkwa Flos. Through this method, we discovered the toxicity was enhanced through the formation of a supramolecular complex from Genkwa Flos/glycyrrhizic acid. The morphology and size distribution of the self-assembled nanoparticles were characterized by scanning electron microscopy and dynamic light scattering Furthermore, a total of 58 constituents (eight diterpenoids, 35 flavonoids, five phenylpropanoids, four nucleosides, two amino acids, and four other compounds) consisted from the supramolecular complex were identified through accurate-mass measurements in full-scan MS/data-dependent MS/MS mode. Based on the hydrophobic interaction of glycyrrhizic acid with yuanhuacine (one of main ingredients from Genkwa Flos), the supramolecular self-assembly mechanism was revealed with proton nuclear magnetic resonance (1H-NMR) and NOESY 2D NMR. The toxicity of Genkwa Flos and Genkwa Flos/glycyrrhizic acid supramolecular complex were compared through in vitro studies on L-02 cells using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay; and 4',6-diamidino-2-phenylindole (DAPI) staining was performed to further confirm the enhancement inhibition of Genkwa Flos/glycyrrhizic acid supramolecular complex than Genkwa Flos. This study provides fundamental scientific evidence of the formation of a self-assembled phytochemical supramolecular when Genkwa Flos and glycyrrhizic acid are combined, enabling to understand their clinical incompatibility and contraindication.

[Method and application of proteomics in study of targets of traditional Chinese medicines].

The study on the targets of traditional Chinese medicine is an important part of researchers using modern scientific language to clarify the mechanism of traditional Chinese medicine. However, the research on the targets of Chinese medicine is full of challenges due to the complexity of active ingredients. As a branch of systems biology, proteomics focus on specific proteins in living organisms from a holistic perspective, which significantly improves the efficiency of targets discovery and has obvious advantages in the research of targets of Chinese medicine. Based on relevant literature and different methods used in targets of Chinese medicine, proteomics can be divided into chemical proteomics, differential proteomics and quantitative proteomics. The applications of the above three methods are illustrated in this paper as well, which will provide new methods and ideas for the study of the mechanism of Chinese medicine in the future.

Enhanced adsorption of arsenite from aqueous solution by an iron-doped electrospun chitosan nanofiber mat: Preparation, characterization and performance.

A novel iron-doped chitosan electrospun nanofiber mat (Fe@CTS ENM) was synthesized, which was proven to be effective for the removal of arsenite (As(III)) from water at neutral pH condition. The physiochemical properties and adsorption mechanism were explored by SEM-EDS and X-ray photoelectron spectroscopy (XPS). Batch adsorption experiments were carried out to evaluate the As(III) adsorption performance of the Fe@CTS ENM with various process parameters, such as adsorbent dose, solution pH, initial As(III) concentration, contact time, ionic strength, coexisting anions, and natural organic matter. The experimental results indicated that the maximum adsorption capacity was up to 36.1 mg g-1. Especially, when the adsorbent dosage was higher than 0.3 g L-1, the As(III) concentration was reduced from 100 µg L-1 to less than 10 µg L-1, which indicated the Fe@CTS ENM could effectively remove trace As(III) from water over a wide pH range (from 3.3 to 7.5). Kinetics study demonstrated that the adsorption equilibrium was achieved within 2.0 h, corresponding to a fast uptake of As(III). The presence of common co-ions and humic acid had little effect on the As(III) adsorption. XPS analysis suggested that the FeO, COH, COC and CN groups on the adsorbent surface play dominant roles in the adsorption of As(III). Adsorption-desorption regeneration test further demonstrated that no appreciable loss in the adsorption capacities was observed, which confirmed that the Fe@CTS ENM maintained a desirable life cycle that was free of complex synthesis processes, expensive and toxic materials, qualifying it as an efficient and low-cost As(III) adsorbent.

Preparation, characterization and performance of an electrospun carbon nanofiber mat applied in hexavalent chromium removal from aqueous solution.

Hexavalent chromium, Cr(VI), a highly toxic oxyanion known as a carcinogen and mutagen, is an issue of concern due to its adverse impact on human health. Therefore, development of effective technologies and/or materials for Cr(VI) removal from water has been of great interest for researchers. In this study, an electrospun carbon nanofiber (CNF) mat was prepared via electrospinning polyacrylonitrile (PAN), followed by thermal pre-oxidation and carbonization. Scanning electron microscopy (SEM) observation showed that the fiber diameter of the CNF with carbonization temperature of 950°C (CNF950) was about 266 nm. Potentiometric titration analysis demonstrated that the point of zero charge pH (pHpzc) of CNF950 was around 7.93. CNF950 demonstrated high adsorption capacity and fast adsorption kinetics for Cr(VI) at pH < 3. Langmuir isotherm calculations showed that the maximum adsorption capacity of Cr(VI) on CNF950 was 118.8 mg/g at pH 2. The adsorption isotherm of Cr(VI) on CNF950 was well described by the Redlich-Peterson model, revealing that Cr(VI) adsorption was the result of a combination of monolayer and multilayer adsorption, depending on the initial Cr(VI) concentration. Solution pH greatly affected Cr(VI) adsorption onto CNF950 due to the electrostatic interaction, and the adsorption capacity was relatively high when pH was below 3. X-ray photoelectron spectroscopy (XPS) analysis revealed that the removal of Cr(VI) might be the result of a combination of redox reaction and electrostatic adsorption. The adsorption-saturated CNF950 could be regenerated by NaOH solution. This study extends the potential applicability of electrospun CNF mats for Cr(VI)-contaminated water purification.

Assessment of the fate of silver nanoparticles in the A(2)O-MBR system.

In this study, we employed a bench scale A(2)O-MBR (anaerobic-anoxic-oxic membrane bioreactor) system to systematically investigate the behavior and distribution of silver nanoparticles (AgNPs) in the activated sludge. The results showed that AgNPs would aggregate and form Ag-sulfur complexes in the activated sludge, and the dissolved silver only reached 13.6 µg/L when AgNPs of 5mg/L was spiked into the A(2)O-MBR. The long-term mass balance analysis showed that most of the silver contents were accumulated in the bioreactor and wasted excess sludge. Only a small fraction (less than 0.5%) of silver could get across the hollow fiber membranes with 0.1 µm nominal pore size in the effluent. In addition, the comparison between total AgNP concentration in aerobic sludge supernatant and effluent suggested that the membrane modules played a role in controlling the discharge of AgNPs into the effluent, especially under a higher influent concentration of AgNPs. Our results also showed that the adsorbed AgNPs or silver complexes in activated sludge still could release dissolved silver at the ambient pH. Thus, since activated sludge could be a sink for AgNPs, the risks of AgNPs in wasted excess sludge during utilization and disposal should be further studied.

Genome-Wide Association Study of Grain Appearance and Milling Quality in a Worldwide Collection of Indica Rice Germplasm.

Grain appearance quality and milling quality are the main determinants of market value of rice. Breeding for improved grain quality is a major objective of rice breeding worldwide. Identification of genes/QTL controlling quality traits is the prerequisite for increasing breeding efficiency through marker-assisted selection. Here, we reported a genome-wide association study in indica rice to identify QTL associated with 10 appearance and milling quality related traits, including grain length, grain width, grain length to width ratio, grain thickness, thousand grain weight, degree of endosperm chalkiness, percentage of grains with chalkiness, brown rice rate, milled rice rate and head milled rice rate. A diversity panel consisting of 272 indica accessions collected worldwide was evaluated in four locations including Hangzhou, Jingzhou, Sanya and Shenzhen representing indica rice production environments in China and genotyped using genotyping-by-sequencing and Diversity Arrays Technology based on next-generation sequencing technique called DArTseq™. A wide range of variation was observed for all traits in all environments. A total of 16 different association analysis models were compared to determine the best model for each trait-environment combination. Association mapping based on 18,824 high quality markers yielded 38 QTL for the 10 traits. Five of the detected QTL corresponded to known genes or fine mapped QTL. Among the 33 novel QTL identified, qDEC1.1 (qGLWR1.1), qBRR2.2 (qGL2.1), qTGW2.1 (qGL2.2), qGW11.1 (qMRR11.1) and qGL7.1 affected multiple traits with relatively large effects and/or were detected in multiple environments. The research provided an insight of the genetic architecture of rice grain quality and important information for mining genes/QTL with large effects within indica accessions for rice breeding.

[A wireless implantable stimulating and ECG monitoring system for animal models of chronic atrial fibrillation].

The rapid atrial pacing model is one of the most popular atrial fibrillation animal models. In this paper, a novel implementation of wireless implantable stimulating and ECG monitoring system is described based on the requirements of rapid atrial pacing model. Hardware circuits and software structure of the system are introduced. And test outcomes through in-vitro simulation and in-vivo animal models are presented. After verified by animal tests, the system can be used to initiate and monitor chronic atrial fibriation in real time.

Removal of silver nanoparticles by coagulation processes.

Commercial use of silver nanoparticles (AgNPs) will lead to a potential route for human exposure via potable water. Coagulation followed by sedimentation, as a conventional technique in the drinking water treatment facilities, may become an important barrier to prevent human from AgNP exposures. This study investigated the removal of AgNP suspensions by four regular coagulants. In the aluminum sulfate and ferric chloride coagulation systems, the water parameters slightly affected the AgNP removal. However, in the poly aluminum chloride and polyferric sulfate coagulation systems, the optimal removal efficiencies were achieved at pH 7.5, while higher or lower of pH could reduce the AgNP removal. Besides, the increasing natural organic matter (NOM) would reduce the AgNP removal, while Ca(2+) and suspended solids concentrations would also affect the AgNP removal. In addition, results from the transmission electron microscopy and X-ray diffraction showed AgNPs or silver-containing nanoparticles were adsorbed onto the flocs. Finally, natural water samples were used to validate AgNP removal by coagulation. This study suggests that in the case of release of AgNPs into the source water, the traditional water treatment process, coagulation/sedimentation, can remove AgNPs and minimize the silver ion concentration under the well-optimized conditions.

Reaction of silver nanoparticles in the disinfection process.

This study investigated the dissolution, aggregation, and reaction kinetics of silver nanoparticles (AgNPs) with the three types of water disinfectants (ultraviolet, sodium hypochlorite, and ozone) under the different conditions of pH, ionic strength, or humic acid (HA). The physicochemical changes of AgNPs were measured by using UV-Vis spectroscopy, transmission electron microscopy, and inductively coupled plasma optical emission spectrometer. The results showed that when AgNPs contacted the disinfectants, oxidative dissolution was the primary reaction. In addition, the reaction kinetics studies revealed that the reaction rate of AgNPs with disinfectants was significantly influenced by different disinfectants along with different pH and the presence of sodium nitrate and HA. Our research demonstrated the potential effect of disinfectants on AgNPs, which will improve our understanding of the fate of AgNPs in the disinfection processes in the water and wastewater treatment plant.