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Mesotrione is considered as an effective triketone herbicide for the control of major broadleaf grasses and some Gramineae weeds. However, over-application of mesotrione poses significant environmental and ecological hazards. The development of a mesotrione fluorescent sensor is essential for detecting mesotrione. A novel fluorescent probe (nitrogen and sulfur co-doped graphene quantum dots (N, S-GQDs)) was designed for the rapid analysis of mesotrione in real water samples. N, S-GQDs synthesized by pyrolytic carbonation have the multilayer graphene structure with the size range of 9.8–29.1 nm, the average size of 19.2 nm, and the average height of 9.7 nm. The fluorescent probe was capable of emitting high-intensity fluorescence. And when mesotrione was mixed with the fluorescent probe, the fluorescence of the probe was rapidly quenched by static quenching and the internal filter effect. The fluorescent probe provided great sensitivity and selectivity in the linear range of 0.5–15 and 15–700 μM for the detection of mesotrione with the detection limit (LOD) of 0.26 μM. Noticeably, real sample tests illustrated the use of the fluorescent probe for mesotrione was a promising strategy. [ABSTRACT FROM AUTHOR]

Deep coal is highly susceptible to dynamic disasters such as rock bursts under the influence of mining. Further exploration of the damage mechanism of coal specimens subjected to cyclic disturbance under different stress conditions is necessary. This study conducted cyclic disturbance failure experiments with coal specimens under different confining pressures, and the acoustic emission (AE) and electromagnetic radiation (EMR) signals were collected. The results show that, under the coupling effect of high stress and disturbance loading, the higher the confining pressure, the greater the disturbance the coal specimen can bear, and most of the specimens are fractured in the loading and unloading stage. Compared with uniaxial loading, the EMR response of coal specimens in the compaction stage is weakened after applying confining pressure. It can also be observed that the greater the confining pressure, the more intense the AE and EMR changes during the rupture of the coal specimen. The confining pressure is positively correlated with the degree of coal fragmentation. This correlation implies that the larger the confining pressure, the smaller the fractal dimension of coal fragments. The intrinsic driving mechanism of coal fracturing was analyzed from an energy perspective. The effects of confining pressure and disturbance loading and unloading cause coal specimens to accumulate more elastic strain energy before fracture, decreasing the post-peak fracture energy and residual strain energy. This study has theoretical reference in preventing and controlling dynamic disasters induced by a disturbance in deep coal mining. [ABSTRACT FROM AUTHOR]

Screening for persistent organic pollutants (POPs) in food is a complex and challenging process, as POPs can be present in very low levels and can be difficult to detect. Herein, we developed an ultrasensitive biosensor based on a rolling circle amplification (RCA) platform using a glucometer to determine POP. The biosensor was constructed using gold nanoparticle probes modified with antibodies and dozens of primers, magnetic microparticle probes conjugated with haptens, and targets. After competition, RCA reactions are triggered, numerous RCA products hybridize with the ssDNA-invertase, and the target is successfully transformed into glucose. Using ractopamine as a model analyte, this strategy obtained a linear detection range of 0.038–5.00 ng mL−1 and a detection limit of 0.0158 ng mL−1, which was preliminarily verified by screening in real samples. Compared with conventional immunoassays, this biosensor utilizes the high efficiency of RCA and the portable properties of a glucometer, which effectively improves the sensitivity and simplifies the procedures using magnetic separation technology. Moreover, it has been successfully applied to ractopamine determination in animal-derived foods, revealing its potential as a promising tool for POP screening. [ABSTRACT FROM AUTHOR]

Flame retardant polyurethane was synthesized via introducing thermally reversible covalent Diels–Alder (DA) adducts into the polyurethane main chain. Firstly, furan-terminated polyurethane prepolymer(PU-Furan) was synthesized from the reaction between isocyanate-terminated prepolymer with or without DOPO-based polyester polyols and furfuryl amine. Secondly, polyurethane with DA adducts (PU-DA) was obtained via Diels–Alder reaction between PU-Furan and commercial 1,1′-(methylenedi-1,4-phenylene) bismaleimide. PU-Furan and PU-DA were characterized by DSC, TGA and 1H NMR, confirming the introduction of the DA adducts into the polyurethane chain. The results of the limiting oxygen index test, Underwriter Laboratory 94 vertical burning (UL-94) test and cone calorimeter test demonstrated that the introduction of the DA adducts improved the flame retardancy of the polyurethane significantly, especially when the polyurethane with flame-retardant element P, due to the synergism flame-resistant effect between flame-retardant element P and thermally reversible DA adducts. [ABSTRACT FROM AUTHOR]

The utilization of deep mineral resources is severely restricted by dynamic disasters, such as rock burst, caused by mining disturbances. This study is aimed at investigating the instability failure mechanism and precursory response of coal specimen, with the aid of acoustic emission (AE) monitoring, under triaxial loading and unloading disturbance. The AE time-varying characteristics were analyzed, the crack propagation mode was explored, and the statistical b value and βt value (damage parameters) of AE events were introduced to evaluate the damage state of the loaded coal under disturbance. The results show that: the dynamic disturbance loads will accelerate the deformation process of coal specimen under high static confining stress, resulting in a positive relation between the AE characteristic parameters (AE counts and energy) and the increasing disturbance amplitude. The proportion of low-frequency and high-amplitude AE signals increases with the disturbance amplitude, indicating the disturbance with large amplitude will promote the formation of large-magnitude cracking events. Those stress-induced cracks, judged from the RA-AF value of AE signals, are mainly tensile mode (i.e., mode-I) under the applied disturbance load, but shear cracks are the critical factor affecting the instability and failure of the loaded coal specimen. Both the b value and βt value can reflect the time-varying evolution process of internal damage for the loaded coal specimen. The sudden decreasing of the b value together with the exponential increasing of the βt value can be regarded as a short-impending precursor indicator for the coal instability and failure. The results of this study will provide some experiment basic and theoretical guidance for dynamic disaster monitoring and early-warning during the deep coal mining. Highlights: The instability failure mechanism and the precursory response of coal specimens under triaxial loading and unloading disturbance were investigated. By analyzing the AE characteristic parameters, the internal damage evolution processes, crack propagation mode and the mechanisms of disturbance were studied. The damage accumulation process and precursor warning information of coal instability failure are extracted by the b and βt values. [ABSTRACT FROM AUTHOR]

The Zoujiashan uranium deposit in the Xiangshan ore field is the largest volcanic-related uranium deposit in China. Hematite- and fluorite-type ores are the predominant mineralization styles. Hematitization in the Xiangshan ore field is closely associated with uranium mineralization, mainly occurring as hematitized rocks enclosing fluorite-type vein ores developed in pre-ore illitized porphyritic lava. Detailed petrographic and mass balance calculation studies were conducted to evaluate the mechanisms for uranium precipitation and mass transfer during hematitization. Petrographic observations suggest that in the hematitized rocks, orthoclase is more altered than plagioclase, and quartz dissolution is common, whereas in the illitized rocks, pyrite commonly occurs within the altered biotite grains, and chlorite grains are locally found. Mass balance calculations indicate that Na2O and U were gained, K2O, CaO and SiO2 were lost, whereas Fe2O3-t remained more or less constant during hematitization. These observations suggest that the hydrothermal fluids were Na- and U-rich and Ca-K-poor, and the Fe2+ used for hematitization was locally derived, most likely from biotite, pyrite and chlorite in the host rocks. The Fe2+ is inferred to have played the role of reductant to precipitate uranium, and calculation indicates that oxidation of Fe2+ provided by host rocks is sufficient to form ores of economic significance. Consequently, the hematite-type ore is interpreted to be generated by the reaction between oxidized ore fluids and reduced components in host rocks. The development of calcite and pyrite in the fluorite ores suggests that perhaps mixing between the U-rich fluid and another fluid carrying reduced sulfur and carbon may have also contributed to uranium mineralization, in addition to temperature and pressure drop associated with the veining. [ABSTRACT FROM AUTHOR]

Purpose: This study assessed effect of food on pharmacokinetics (PK) and safety of fuzuloparib capsules.A randomized, open-label, two-cycle, two-sequence, crossover clinical trial was conducted. 20 subjects were randomly assigned to 2 groups at a 1:1 ratio. The first group subjects were orally administered 150 mg fuzuloparib capsules under fasting condition in first dosing cycle. The same dose of fuzuloparib capsules were taken under postprandial state after a 7-day washout period. The second group was reversed. 3 ml whole blood was collected at each blood collection point until 72 h post dose. PK parameters were calculated. Furthermore, safety assessment was performed.The time to maximum concentration (Tmax) was prolonged to 3 h and maximum concentration (Cmax) decreased by 18.6% on high-fat diets. 90% confidence intervals (CIs) of geometric mean ratios (GMRs) for Cmax, area under the concentration–time curve from time zero to time t (AUC0−t), and area under the concentration–time curve extrapolated to infinity (AUC0−∞) after high-fat meal were 71.6–92.6%, 81.7–102.7% and 81.6–102.5%, respectively. All treatment-emergent adverse events (TEAEs) were grade 1; No serious adverse events (SAEs), serious unexpected suspected adverse reaction (SUSAR) or deaths were reported.Food decreased the absorption rate and slowed time to peak exposure of fuzuloparib capsules, without impact on absorption extent. Dosing with food was found to be safe for fuzuloparib capsules in this study.This study was registered with chinadrugtrials.org.cn (identifier: CTR20221498).Methods: This study assessed effect of food on pharmacokinetics (PK) and safety of fuzuloparib capsules.A randomized, open-label, two-cycle, two-sequence, crossover clinical trial was conducted. 20 subjects were randomly assigned to 2 groups at a 1:1 ratio. The first group subjects were orally administered 150 mg fuzuloparib capsules under fasting condition in first dosing cycle. The same dose of fuzuloparib capsules were taken under postprandial state after a 7-day washout period. The second group was reversed. 3 ml whole blood was collected at each blood collection point until 72 h post dose. PK parameters were calculated. Furthermore, safety assessment was performed.The time to maximum concentration (Tmax) was prolonged to 3 h and maximum concentration (Cmax) decreased by 18.6% on high-fat diets. 90% confidence intervals (CIs) of geometric mean ratios (GMRs) for Cmax, area under the concentration–time curve from time zero to time t (AUC0−t), and area under the concentration–time curve extrapolated to infinity (AUC0−∞) after high-fat meal were 71.6–92.6%, 81.7–102.7% and 81.6–102.5%, respectively. All treatment-emergent adverse events (TEAEs) were grade 1; No serious adverse events (SAEs), serious unexpected suspected adverse reaction (SUSAR) or deaths were reported.Food decreased the absorption rate and slowed time to peak exposure of fuzuloparib capsules, without impact on absorption extent. Dosing with food was found to be safe for fuzuloparib capsules in this study.This study was registered with chinadrugtrials.org.cn (identifier: CTR20221498).Results: This study assessed effect of food on pharmacokinetics (PK) and safety of fuzuloparib capsules.A randomized, open-label, two-cycle, two-sequence, crossover clinical trial was conducted. 20 subjects were randomly assigned to 2 groups at a 1:1 ratio. The first group subjects were orally administered 150 mg fuzuloparib capsules under fasting condition in first dosing cycle. The same dose of fuzuloparib capsules were taken under postprandial state after a 7-day washout period. The second group was reversed. 3 ml whole blood was collected at each blood collection point until 72 h post dose. PK parameters were calculated. Furthermore, safety assessment was performed.The time to maximum concentration (Tmax) was prolonged to 3 h and maximum concentration (Cmax) decreased by 18.6% on high-fat diets. 90% confidence intervals (CIs) of geometric mean ratios (GMRs) for Cmax, area under the concentration–time curve from time zero to time t (AUC0−t), and area under the concentration–time curve extrapolated to infinity (AUC0−∞) after high-fat meal were 71.6–92.6%, 81.7–102.7% and 81.6–102.5%, respectively. All treatment-emergent adverse events (TEAEs) were grade 1; No serious adverse events (SAEs), serious unexpected suspected adverse reaction (SUSAR) or deaths were reported.Food decreased the absorption rate and slowed time to peak exposure of fuzuloparib capsules, without impact on absorption extent. Dosing with food was found to be safe for fuzuloparib capsules in this study.This study was registered with chinadrugtrials.org.cn (identifier: CTR20221498).Conclusion: This study assessed effect of food on pharmacokinetics (PK) and safety of fuzuloparib capsules.A randomized, open-label, two-cycle, two-sequence, crossover clinical trial was conducted. 20 subjects were randomly assigned to 2 groups at a 1:1 ratio. The first group subjects were orally administered 150 mg fuzuloparib capsules under fasting condition in first dosing cycle. The same dose of fuzuloparib capsules were taken under postprandial state after a 7-day washout period. The second group was reversed. 3 ml whole blood was collected at each blood collection point until 72 h post dose. PK parameters were calculated. Furthermore, safety assessment was performed.The time to maximum concentration (Tmax) was prolonged to 3 h and maximum concentration (Cmax) decreased by 18.6% on high-fat diets. 90% confidence intervals (CIs) of geometric mean ratios (GMRs) for Cmax, area under the concentration–time curve from time zero to time t (AUC0−t), and area under the concentration–time curve extrapolated to infinity (AUC0−∞) after high-fat meal were 71.6–92.6%, 81.7–102.7% and 81.6–102.5%, respectively. All treatment-emergent adverse events (TEAEs) were grade 1; No serious adverse events (SAEs), serious unexpected suspected adverse reaction (SUSAR) or deaths were reported.Food decreased the absorption rate and slowed time to peak exposure of fuzuloparib capsules, without impact on absorption extent. Dosing with food was found to be safe for fuzuloparib capsules in this study.This study was registered with chinadrugtrials.org.cn (identifier: CTR20221498).Clinical trial registration.: This study assessed effect of food on pharmacokinetics (PK) and safety of fuzuloparib capsules.A randomized, open-label, two-cycle, two-sequence, crossover clinical trial was conducted. 20 subjects were randomly assigned to 2 groups at a 1:1 ratio. The first group subjects were orally administered 150 mg fuzuloparib capsules under fasting condition in first dosing cycle. The same dose of fuzuloparib capsules were taken under postprandial state after a 7-day washout period. The second group was reversed. 3 ml whole blood was collected at each blood collection point until 72 h post dose. PK parameters were calculated. Furthermore, safety assessment was performed.The time to maximum concentration (Tmax) was prolonged to 3 h and maximum concentration (Cmax) decreased by 18.6% on high-fat diets. 90% confidence intervals (CIs) of geometric mean ratios (GMRs) for Cmax, area under the concentration–time curve from time zero to time t (AUC0−t), and area under the concentration–time curve extrapolated to infinity (AUC0−∞) after high-fat meal were 71.6–92.6%, 81.7–102.7% and 81.6–102.5%, respectively. All treatment-emergent adverse events (TEAEs) were grade 1; No serious adverse events (SAEs), serious unexpected suspected adverse reaction (SUSAR) or deaths were reported.Food decreased the absorption rate and slowed time to peak exposure of fuzuloparib capsules, without impact on absorption extent. Dosing with food was found to be safe for fuzuloparib capsules in this study.This study was registered with chinadrugtrials.org.cn (identifier: CTR20221498). [ABSTRACT FROM AUTHOR]

The upper catchment of the Miyun reservoir is an important drinking water source in Beijing. In recent years, researchers have used the soil conservation service curve number (SCS-CN) model to calculate surface runoff for the district. Although the runoff forecasting accuracy was unsatisfactory, the lack of understanding of rainfall processes and their influence on runoff may explain the observed deviations. Our study sought to optimize and assess the SCS-CN model simulation accuracy for the district by proposing an SCS-CN calculation method for each runoff event (CNt) based on observation data for 253 rainfall and runoff events from 7 plots in the Miyun Shixia watershed. This study elucidated a significant positive correlation between the ratio of CNt and the average SCS-CN (CN1), as well as the ratio of the maximum X-minute rainfall amount (PX) to the total rainfall amount for each rainfall event (P). Furthermore, a calculation method involving power function equations between CNt/CN1 and PX/P was proposed for CNt. When X = 5 min and the initial abstraction ratio (λ) = 0.01, the simulation performance of the optimized model was the highest, with a Nash-Sutcliffe efficiency coefficient of 0.791, which was significantly higher than that of the non-optimized SCS-CN model. The simulation performance for bare and cultivated land was higher than that of other land uses, with Ef values of 0.831 and 0.828, respectively. Future research should focus on improving the prediction accuracy of runoff events resulting from high-intensity and short-duration rainfall events. [ABSTRACT FROM AUTHOR]

In this work, the effect of Cu addition on the microstructure and corrosion passivation behavior of Sn alloyed ferritic stainless steel in 3.5 wt.% NaCl solution at 30 °C was investigated by optical microscope (OM), scanning electron microscope (SEM), energy-dispersion spectrum (EDS), potentiodynamic polarization curve and x-ray photoelectron spectroscopy (XPS). The results indicate that Cu addition has certain effect on grain refinement of ferritic stainless steel. Meanwhile, Cu addition has little influence on the cathodic corrosion process of ferritic stainless steel in 3.5 wt.% NaCl solution but shows beneficial effect on enhancing both the corrosion resistance of steel substrate and its passivation behavior. It has been found that the deposition of Cu particles at the bottom of corrosion pits is responsible for the better corrosion resistance and passivation behavior of ferritic stainless steel. Moreover, there is synergistic effect between Sn and Cu on enhancing the corrosion resistance of ferric stainless steel matrix and improving its passivation behavior in NaCl solution. [ABSTRACT FROM AUTHOR]

Schistosoma is the causative agent of schistosomiasis, a common infectious disease distributed worldwide. Our previous phosphoproteomic analysis suggested that glycogen synthase kinase 3 (GSK3), a conserved protein kinase in eukaryotes, is likely involved in protein phosphorylation of Schistosoma japonicum. Here, we aimed to identify the interacting partners of S. japonicum GSK3β (SjGSK3β) and to evaluate its role in parasite survival. Toward these ends, we determined the transcription levels of SjGSK3β at different developmental stages and identified its interacting partners of SjGSK3β by screening a yeast two-hybrid S. japonicum cDNA library. We further used RNA interference (RNAi) to inhibit the expression of SjGSK3β in adult worms in vitro and examined the resultant changes in transcription of its putative interacting proteins and in worm viability compared with those of control worms. Reverse transcription-quantitative polymerase chain analysis indicated that SjGSK3β is expressed throughout the life cycle of S. japonicum, with higher expression levels detected in the eggs and relatively higher expression level found in male worms than in female worms. By screening the yeast two-hybrid library, eight proteins were identified as potentially interacting with SjGSK3β including cell division cycle 37 homolog (Cdc37), 14-3-3 protein, tegument antigen (I(H)A), V-ATPase proteolipid subunit, myosin alkali light chain 1, and three proteins without recognized functional domains. In addition, SjGSK3β RNAi reduced the SjGSK3β gene transcript level, leading to a significant decrease in kinase activity, cell viability, and worm survival. Collectively, these findings suggested that SjGSK3β may interact with its partner proteins to influence worm survival by regulating kinase activity. [ABSTRACT FROM AUTHOR]

Silky chicken is a breed of chickens with black skin and slow growth rate used in Chinese traditional medicine, whereas Arbor Acres broiler is a well-known commercial breed in the poultry industry, it is featured by a large size, rapid-growth rate, high feed-conversion rate and strong adaptability. The difference in their rate of growth may be primarily related to different mechanism for glucose metabolism. Here we compared the insulin sensitivity of the two breeds; we investigated the temporal changes (at 0 min, 120 min and 240 min) of serum insulin and other biochemical parameters and determined the spatio-temporal changes of gene mRNA abundance in response to exogenous insulin (80 μg/kg body weight). The results indicated that: (1) Silky chickens showed stronger blood glucose recovery than broilers in the insulin resistance test. (2) The serum urea level in Silky chickens was twice of broilers; exogenous insulin significantly up-regulated serum uric acid level in Silky fowls in a time-dependent manner and increased serum cholesterol content at 120 min. (3) Two breeds showed distinctly different temporal changed in serum insulin in response to exogenous insulin stimulation. The fasting serum insulin concentration of broilers was three-fold of Silky chickens at the basal state; it decreased significantly after insulin injection and the levels at 120 min and 240 min of broilers were only 23% (P < 0.01) and 14% (P < 0.01) of the basal state, respectively. Whereas the serum insulin content in Silky chickens showed stronger recovery, and the 240 min level was close to the 0 min level. (4) GLUT2, GLUT12, neuropeptide Y and insulin receptor (IR) were predominantly expressed in the liver, pectoralis major, olfactory bulb and pancreas, respectively, where these genes presented stronger insulin sensitivity. In addition, the IR mRNA level was strongly positively with the GLUT12 level. In conclusion, our findings suggested that Silky chickens have a stronger ability to regulate glucose homeostasis than broilers, owing to their higher IR levels in the basal state, stronger serum insulin homeostasis and candidate genes functioning primarily in their predominantly expressed tissue in response to exogenous insulin. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA (mtDNA) copy number reflects the abundance of mitochondria in cells and is dependent on the energy requirements of tissues. We hypothesized that the mtDNA copy number in poultry may change with age and tissue, and feed restriction may affect the growth and health of poultry by changing mtDNA content in a tissue-specific pattern. TaqMan real-time PCR was used to quantify mtDNA copy number using three different segments of the mitochondrial genome (D-loop, ATP6, and ND6) relative to the nuclear single-copy preproglucagon gene (GCG). The effect of sex, age, and dietary restriction (quantitative, energy, and protein restriction) on mtDNA copy number variation in the tissues of broilers was investigated. We found that mtDNA copy number varied among tissues (P < 0.01) and presented a distinct change in spatiotemporal pattern. After hatching, the number of mtDNA copies significantly decreased with age in the liver and increased in muscle tissues, including heart, pectoralis, and leg muscles. Newborn broilers (unfed) and embryos (E 11 and E 17) had similar mtDNA contents in muscle tissues. Among 42 d broilers, females had a higher mtDNA copy number than males in the tissues examined. Feed restriction (8–21 d) significantly reduced the body weight but did not significantly change the mtDNA copy number of 21 d broilers. After three weeks of compensatory growth (22–42 d), only the body weight of broilers with a quantitatively restricted diet remained significantly lower than that of broilers in the control group (P < 0.05), while any type of early feed restriction significantly reduced the mtDNA copy number in muscle tissues of 42 d broilers. In summary, the mtDNA copy number of broilers was regulated in a tissue- and age-specific manner. A similar pattern of spatiotemporal change in response to early feed restriction was found in the mtDNA content of muscle tissues, including cardiac and skeletal muscle, whereas liver mtDNA content changed differently with age and dietary restriction. It seems that early restrictions in feed could effectively lower the mtDNA content in muscle cells to reduce the tissue overload in broilers at 42 d to some degree. [ABSTRACT FROM AUTHOR]

In the context of climate change and over-exploitation of water resources, water shortage and water pollution in arid regions have become major constraints to local sustainable development. In this study, we established a Soil and Water Assessment Tool (SWAT) model for simulating non-point source (NPS) pollution in the irrigation area of the lower reaches of the Kaidu River Basin, based on spatial and attribute data (2010–2014). Four climate change scenarios (2040–2044) and two agricultural management scenarios were input into the SWAT model to quantify the effects of climate change and agricultural management on solvents and solutes of pollutants in the study area. The simulation results show that compared to the reference period (2010–2014), with a decline in streamflow from the Kaidu River, the average annual irrigation water consumption is expected to decrease by 3.84x108 m3 or 8.87% during the period of 2040–2044. Meanwhile, the average annual total nitrogen (TN) and total phosphorus (TP) in agricultural drainage canals will also increase by 10.50% and 30.06%, respectively. Through the implementation of agricultural management measures, the TN and TP in farmland drainage can be reduced by 14.49% and 16.03%, respectively, reaching 661.56 t and 12.99 t, accordingly, and the increasing water efficiency can save irrigation water consumption by 4.41 x108 m3 or 4.77%. The results indicate that although the water environment in the irrigation area in the lower reaches of the Kaidu River Basin is deteriorating, the situation can be improved by implementing appropriate agricultural production methods. The quantitative analysis results of NPS pollutants in the irrigation area under different scenarios provide a scientific basis for water environmental management in the Kaidu River Basin. [ABSTRACT FROM AUTHOR]

Seafloor deformation or displacement in methane hydrate production areas is a significant environmental problem that can cause considerable damage. This paper describes a conceptual design for monitoring seafloor deformation that differs from existing monitoring methods that include acoustic and pressure sensors, which have high costs and are only suitable for detecting vertical deformation. The proposed monitoring system is vertically mounted in each monitoring well to detect the displacement of submarine soil layers at different depths and to provide visual feedback by displaying three-dimensional images in real time. To reduce the drift error and to obtain more reliable angle estimates, a Kalman filter algorithm is used to combine the data that are measured using a gyroscope and a digital compass. The stability and accuracy of the system are tested both in real-time test and off-line experiment, and the total errors of the azimuth and tilt angle are less than 0.03° and 0.19° in the static off-line experiment, respectively. [ABSTRACT FROM AUTHOR]

The authors have developed a competitive immunoassay for the model pesticide triazophos (TRIAZ). The method is based on the use of only one monoclonal antibody immobilized on multi-labeled gold nanoparticle (AuNP) probes. The immunoassay uses two sets of probe. The first is a multi-labeled AuNP probe that carries monoclonal antibody (mcAb), single-stranded DNA (ssDNA) and horse radish peroxidase (HRP). The second is a magnetic microparticle (MMP) probe that is obtained by coating MMPs with ovalbumin coupled to TRIAZ. Free TRIAZ and MMP-immobilized TRIAZ compete for binding to the mcAb on the surface of the AuNPs. Because TRIAZ is a rather small molecule, it cannot be bound by two antibodies. The competitive immunoassay overcomes the limitations of small molecule detection using one kind of mcAb only. Sensitive transduction of the immunoreaction is accomplished by enzymatically catalyzed amplified. TRIAZ was quantified by a conventional ELISA and by the immunoassay presented here. Both method are highly sensitive and well reproducible. The new assay has a linear response in the 15 ng L to 40 μg L TRIAZ concentration range, and a 14 ng L limit of detection which make it more sensitive than the ELISA. The recovery rate in case of spiked samples ranges from 78.4 to 105%, and the RSD is <20%. A good correlation was further established between the results of the immunoassay and those of GC-MS analysis. [ABSTRACT FROM AUTHOR]

To evaluate the relationship between exposure to air pollutants and respiratory emergency room visits, a generalized additive model (GAM) was used to analyze the exposure-effect relationship between air pollutants and respiratory emergency room visits. The results showed that NO, SO, and PM have positive relationships with respiratory disease. Concentration increases of 10 μg/m in NO, SO, and PM corresponded to 3.90% (95%CI 3.56-4.25), 0.81% (95%CI −0.09-1.72), and 0.64% (95%CI 0.55-0.74) increases in respiratory emergency room visits. In addition, there is a strong synergic effect of PM and NO on respiratory diseases. The threshold values of the national standard grade II limits used in Beijing should be adjusted. An appropriate standard could effectively promote a significant decline in respiratory room visits and would eventually be beneficial to air quality management in residential areas. [ABSTRACT FROM AUTHOR]

α-Glucosidase (XcG) from Xanthomonas campestris is an interesting enzyme due to its ability to catalyze transglycosylation reactions using maltose, rather than expensive nucleotide-activated sugars. In this study, two chimerical enzymes, XcG-A and XcG-B, were created by substituting the corresponding region of the XcG gene with gene fragments retrieved from metagenomic DNA samples. The enzymatic characterization results revealed that XcG-A exhibited a significant greater transglycosylation capacity for α-arbutin production and a significantly improved ability to produce α-arbutin-α-glycosides than XcG and XcG-B. [ABSTRACT FROM AUTHOR]

Non-point source (NPS) pollution simulation in the high-precipitation coastal areas of China is difficult because varying annual typhoon incidence leads to highly contrasting rainfall patterns in dry years and wet years. An IMPULSE (Integrated Model of Non-point Sources Pollution Processes) based NPS model of the Changtan Reservoir watershed, which is a typical high-precipitation coastal area in China, was established based on the analysis of point and NPS pollution data, a digital elevation model, and data on land-use, soil, meteorology, economy, and agricultural management practice. Pre-processed pre-rainfall soil moisture levels were introduced during the simulation to model the effects of typhoons on hydrology. Rainfall events were simulated sequentially through the year and the model was calibrated and verified using hydrological and water quality data. Accuracy of the simulated rainfall runoff and water quality in the Changtan watershed was found to be acceptable. The study showed that the NPS modeling system could be applied to the simulation and prediction of NPS loadings in the Changtan Reservoir watershed. [ABSTRACT FROM AUTHOR]

In order to obtain the change in the return laser-pulse peak-power instability with the distance between two communication terminals in a free-space optical communication (FSO) asymmetric link, which uses a corner-cube retroreflector (CCR) and a high peak-power pulse laser, we present the peak power instability of laser pulses retroreflected by the CCR at different distances. The CCR bottom surface was a circle with a diameter of 1 in., and three mirrors of the CCR were coated with silver. The weather was cloudy with winds of Category 4. The distances from the transmitter to the CCR were 120, 1,550, 3,900, and 5,240 m. The laser emitted 100 laser pulses with a peak power of 5 MW at each distance. The results of the experiments show that the increase in both absolute and relative peakpower instabilities with the distance is approximately linear. The absolute peak-power instability is more than 58.7 mV and the relative peak-power instability is more than 11.8 % if the distance increases 1 km. [ABSTRACT FROM AUTHOR]

Drinking water sources are highly valued by authorities for safeguarding the life of a city. Models are widely applied as important and effective tools in the management of water sources. However, it is difficult to apply models in water source management because water managers are often not equipped with the professional knowledge and operational skills necessary for making use of the models. This paper introduces a drinking water source simulation and prediction system that consists of a watershed model, a hydrological model and a water quality model. This system provides methods and technical guidance for the conventional management of water sources and emergency water event response. In this study, the sub-models of the system were developed based on the data of the Jiangdong Reservoir in Xiamen, and the model validation was based on local monitoring data. The hydrological model and water quality model were integrated by computer programming, and the watershed model was indirectly integrated into the system through a network platform. Furthermore, three applications for Jiangdong Reservoir water protection utilizing the system were introduced in this paper, including a conventional simulation, an emergency simulation, and an emergency measures evaluation. [ABSTRACT FROM AUTHOR]

Linear polyurethane was synthesized by Diels-Alder (DA) reaction between a polyurethane prepolymer end-capped with furan rings (MPF) and bismaleimide (BMI). The polymerization kinetics were studied following a preliminary kinetic study of the DA reaction between furfuryl alcohol (FA) and BMI compounds by attenuated total reflection infrared, ultraviolet-visible and in situ H NMR spectroscopies, where in situ H NMR spectroscopy was selected as the analytical method of choice to study the DA reaction between MPF and BMI. The results showed that the reaction followed second-order kinetics, and the most beneficial experimental conditions to maximize conversion were identified. [ABSTRACT FROM AUTHOR]

Water environment security (WES) is defined in terms of three aspects: first, that it meets basic demands due to industrial and domestic usage; second, that it protects public health from acute and chronic threats; and third, that measures are adopted to ensure sustainable ecological functioning of freshwater resources. Limitations associated with current water environment security indicators in China - including inefficiency in terms of environmental monitoring, inappropriate indicators and parameters that do not take sufficient account of local water characteristics, and a lack of management targets -leads to a failure of effective water management. To achieve better water environment management, a systematic approach, encompassing several steps including establish ideal indicator system and narrow down the scope, screen priority pollutants, identify local characteristics and organize discussion workshop, should be followed to establish a comprehensive water environment indicator system. A case study in Suzhou is included to demonstrate the detailed operational procedures used to assess the risks associated with poor management practices relating to water environment security as well as design an appropriate water environment security indicator system. [ABSTRACT FROM AUTHOR]

Characteristics of rainfall runoff from a 3.26 hm urban catchment with predominant land-use as lawn in Xiamen City, South-east China were investigated and analyzed. Water quality and quantity measurements of rainfall runoff were conducted for ten rainfall events over the period March, 2008 to April, 2009. The results indicated that chemical oxygen demand (COD) and total phosphorus (TP) were the major pollutants with event mean concentrations of 56.09 and 0.44 mg·L. From hydrograph and pollutograph analysis of two typical rainfall events, it was clear that the peak rainfall preceded the peak flowrate by about 15-20 min. Meanwhile, concentrations of major pollutants showed multiple peaks and these peaks usually preceded peak flowrate. There were no distinctive first-flush effects except for the rainfall events with the longest rainfall duration and largest runoff volume, which was verified by the fact that the first 30% runoff volume (FF30) carried 39.36% of the total suspended solids (TSS) load, 35.17% of the COD load, 28.13% of the TP load and 39.03% of the nitrate nitrogen load. Multivariate regression analysis further demonstrated that the total runoff volume had a positive correlation with the FF30 of TSS and COD. [ABSTRACT FROM AUTHOR]

A Correction to this paper has been published: https://doi.org/10.1007/s10745-020-00205-w [ABSTRACT FROM AUTHOR]

Thin films with tailored microstructures are an emerging class of materials with applications such as battery electrodes, organic electronics, and biosensors. Such thin film devices typically exhibit a multi-phase microstructure that is confined, and show large anisotropy. Current approaches to microstructure design focus on optimizing bulk properties, by tuning features that are statistically averaged over a representative volume. Here, we report a tool for morphogenesis posed as a graph-based optimization problem that evolves microstructures recognizing confinement and anisotropy constraints. We illustrate the approach by designing optimized morphologies for photovoltaic applications, and evolve an initial morphology into an optimized morphology exhibiting substantially improved short circuit current (68% improvement over a conventional bulk-heterojunction morphology). We show optimized morphologies across a range of thicknesses exhibiting self-similar behavior. Results suggest that thicker films (250 nm) can be used to harvest more incident energy. Our graph based morphogenesis is broadly applicable to microstructure-sensitive design of batteries, biosensors and related applications. MATERIALS DESIGN: The power of graphs Representing microstructures with graphs, and mapping their properties mathematically, can help improve material properties. Morphogenesis is the process of optimizing performance in devices; representing the candidate structure with an appropriate mathematical framework in order to probe their properties and then mapping the structure to a property. Current approaches rely on computationally heavy methods for both stages, but now a team from Iowa State University and University at Buffalo simplify the process by representing the structures with labelled, weighted, undirected graphs. On this basis, one can create a "surrogate" model through generic physics graph descriptors (e.g. path lengths, domain sizes) and weighting functions for the particular property of interest. This approach reveals new designs for improved organic solar cells, but could expanded to other devices. [ABSTRACT FROM AUTHOR]

A novel detection method of small molecules, competitive bio-barcode amplification immunoassay, was developed and described in this report. Through the gold nanoparticles (AuNPs) probe and magnetic nanoparticles (MNPs) probe we prepared, only one monoclonal antibody can be used to detect small molecules. The competitive bio-barcode amplification immunoassay overcomes the obstacle that the bio-barcode assay cannot be used in small molecular detection, as two antibodies are unable to combine to one small molecule due to its small molecular structure. The small molecular compounds, triazophos, were selected as targets for the competitive bio-barcode amplification immunoassay. The linear range of detection was from 0.04 ng mL−1 to 10 ng mL−1, and the limit of detection (LOD) was 0.02 ng mL−1, which was 10-20 folds lower than ELISA (Enzyme Linked Immunosorbent Assay). A practical application of the proposed immunoassay was evaluated by detecting triazophos in real samples. The recovery rate ranged from 72.5% to 110.5%, and the RSD was less than 20%. These results were validated by GC-MS, which indicated that this convenient and sensitive method has great potential for small molecular in real samples. [ABSTRACT FROM AUTHOR]