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Abstract There is a growing problem in China, whereby tomato replant disease is being affected by Fusarium spp., Meloidogyne spp., and Phytophthora spp. To address these pests that live in the soil, we evaluated how well applying a dazomet (DZ) and 1,3-dichloropropene (1,3-D) combination directly to the soil works in three different tomato trials. The combined treatment of DZ + 1,3-D (25 + 10 g a.i. m⁻²), applied at a 50% reduction rate, effectively decreased Meloidogyne spp. populations in the soil by more than 94%. This resulted in low root galling indices of 2.67%, 4.17%, and 10.83% in the different trials. In addition, it significantly decreased the number of Fusarium spp. and Phytophthora spp. colonies by more than 82%, resulting in low root disease indices of 3.33%, 10.00%, and 10.42%, respectively. This also greatly increased tomato yield and profit for growers. The results obtained with DZ alone and methyl bromide (MB) at 50 g a.i. m⁻² were similar. However, these results were better than those obtained with 1,3-D at 20 g a.i. m⁻² alone in controlling soilborne fungi in trials I and III. Compared to the untreated controls and the soil solarization disinfestation treatments, all the chemical treatments performed significantly better. Due to its effectiveness in controlling pests and its economic advantages, soil fumigation with DZ + 1,3-D (25 + 10 g a.i. m⁻²) is recommended in pest management programs for tomato cultivation in China. This treatment is highly effective in managing pests that reside in the soil.

This paper extensively investigates the performance of the representative SBE 3 deep-sea thermometer (Sea-Bird Scientific) under various stepwise pressure conditions. A high-precision pressure-temperature vessel was employed to simulate deep sea environments, conducting systematic pressure experiments with precise temperature control (0.5 mK) across a temperature range of -2 to 35°C and from atmospheric pressure to full ocean depth (0–12700 m). A Standard platinum resistance thermometer (SPRT), isolated from the pressure environment and placed adjacent to the SBE 3, served as a calibration reference throughout the experiments. The drift of the SBE 3, reaching up to 10 mK in this study, was meticulously quantified at varying pressures and temperatures. Subsequently, a linear calibration method was developed, ensuring that the thermometer maintained an accuracy of ±0.0005°C (± 0.5 mK) across all tested high-pressure conditions, including a maximum pressure of 1050 bar. Crucially, this study discusses the negative impact of pressure-induced temperature errors on the estimation of ocean heat content in the Pacific, emphasizing the importance of conducting high-pressure calibration tests before and after oceanographic deployments. These measures are vital for ensuring the accuracy of deep-sea temperature measurements, which are critical for understanding global climate dynamics and improving the calibration of deep-sea sensors.

BackgroundTuberculosis (TB) remains a serious global public health problem. The Mycobacterium tuberculosis (MTB) is responsible for approximately 10 million new TB cases globally each year. This study aimed to investigate transmission pattern and drug resistance of MTB in Shenzhen, China.MethodsA retrospective study on 286 samples from 184 TB patients collected between 2015 and 2018 in Shenzhen Third People’s Hospital was conducted using whole-genome sequencing. Drug susceptibility testing (DST) was performed using both phenotypic DST (pDST) and molecular DST (mDST). Sample diversity was evaluated by SNPs and transmission clusters were identified based on SNP differences of 12 or fewer in genetic clusters.ResultsExcept four samples identified as non-tuberculous mycobacteria, 282 MTB samples (181 patients) underwent mDST, with 244 samples (162 patients) undergoing pDST. The overall multidrug-resistant rate in patients was 22.31% in pDST (12.00% for new patients and 40.82% for retreatment patients) and 34.48% in mDST (20.41% for new patients and 58.21% for retreatment patients). Totally 92 transmission clusters were identified, encompassing 70.21% samples (57.46% patients), with 5 clusters containing samples (15, 5.32%) from different patients (9, 4.97%), indicating recent transmission. The drug-resistant mutations in 36 of 45 transmission clusters (80.00%) were identical in all samples, suggesting the transmission of drug resistance. Patients with multiple samples were categorized into simultaneous sampling (SS) and continuous sampling (CS) groups, revealing significant differences in treatment types, treatment outcomes, residential addresses, and drug resistance types. mDST showed greater accuracy than pDST in SS and CS groups. A novel method based on heterozygous SNPs and two-sample Kolmogorov–Smirnov test were developed and identified 12 (4.26%) samples as mixed infection samples. Six of 12 patients had mixed and pure samples together, and major strains of mixed samples were closer to corresponding pure strains than minor strains.ConclusionsThis retrospective study, conducted at the only municipal hospital specializing in infectious diseases in Shenzhen, provides the opportunity to understand drug resistance of TB patients, which mainly are refractory patients. The study revealed transmission patterns of MTB, analyzed mixed infections, and tracked changes in MTB strains during short/long-term treatment.

Abstract The residue of atrazine in field soils poses a major threat to crop growth in the rotation system, raising concerns about grain security and food safety. Current agricultural production requires more efficient and cost-effective mitigation measures in response to the emerging threat. This study reported the critical concentration (0.1 mg L−1) of atrazine injury to soybean seedlings in soil pore water and how biochar amendment could influence the distribution of atrazine in different soil environments. The results showed that biochar significantly reduced the concentration of atrazine in soil pore water, for example, 0.5% biochar in red (cinnamon, fluvo-aquic, paddy, black) soil reduced atrazine concentration from 0.31 (0.20, 0.18, 0.12, 0.03) mg L−1 to 0.004 (0.002, 0.005, 0.013, 0.011) mg L−1 in pore water (P

Accurate pressure measurement is crucial for understanding ocean dynamics in marine research. However, pressure sensors based on strain measurement principles are significantly affected by temperature variations, impacting the accuracy of depth measurements. This study investigates the SBE37-SM sensor and presents an improved calibration method based on a constant-pressure, variable-temperature scheme that effectively addresses temperature-induced deviations in pressure measurement. Experiments were conducted across a pressure range of 2000 dbar to 6000 dbar and a temperature range of 2 °C to 35 °C, establishing a comprehensive pressure–temperature calibration grid. The results show that, at a pressure of 6000 dbar, temperature-induced variations in readings for brand new SBE37-SM sensors can reach up to 9 dbar, while, for used sensors, they exceed 12 dbar, following a U-shaped trend. After applying a polynomial regression model for calibration, these variations were reduced to within ±0.5 dbar, significantly reducing the measurement uncertainty of the sensors in complex marine environments. This method underscores the necessity of further optimizing the CTD system’s temperature compensation mechanism during calibration and highlights the importance of regular calibration to minimize measurement uncertainty.

Ocean salinity plays an important role in oceanographic research as one of the fundamental parameters. An optical salinometer based on the Michelson interferometer (MI) suitable for in situ measurement in deep-sea environments is proposed in this work, and it features real-time calibration and multichannel multiplexing using the frequency modulated continuous wave (FMCW) technique. The symmetrical sapphire structure used to withstand deep-sea pressure can not only achieve automatic temperature compensation, but also counteract the changes in optical path length under deep-sea pressure. A model formula suitable for optical salinity demodulation is proposed through the nonlinear least squares fitting method. In vertical profile testing, the optical salinometer demonstrated remarkable tracking performance, achieving an error of less than 0.001 psu. The sensor displays a stable salinity demodulation error within ±0.002 psu during a three-month long-term test at a depth of 4000 m. High stability and resolution make this optical salinometer have broad development prospects in ocean observation.

The investment-return model of power system plays an important part in the business model of power system. In previous studies, the financial pressure brought by the proportion of power project investment was neglected. An investment-return model based on asymmetric Nash bargaining was proposed in this paper, which could better reflect the game process of investment-return in the new power system. Firstly, the stakeholders of cooperative game were analyzed so as to establish the framework of cooperative game model. Secondly, combined with various characteristics of new power system, various influencing factors of the cooperative game was estimated. Thirdly, the expression and solution of Nash bargain were put forward. Finally, the availability of the model was verified by an example. The experiment showed that the investment-return model could reflect the process of investment-return of the new power system more completely.

This study evaluated the residue behavior and dissipation dynamics of a new imidacloprid FS 600 seed treatment in potato cultivation systems in Shandong and Jilin, China. Sensitive and accurate UPLC-MS/MS methods were established to quantify imidacloprid residues in potatoes, potato plants, and soil. Results showed that imidacloprid dissipation followed a first-order kinetic model, with half-lives ranging from 6.9 to 26.7 days in plants and 19.8 to 28.9 days in soil. At harvest, the highest average residues in potatoes and soil were 0.778 mg/kg and 0.149 mg/kg, respectively. The dietary risk assessment indicated a chronic risk quotient (CRQ) of 39.73% for adults, indicating minimal risk to human consumers, while the ecological risk quotient (ERQ) and ecotoxicity exposure ratio (TER) revealed low to moderate toxicity to earthworms, warranting caution in the use of this formulation. This research provides valuable data for assessing the safety of imidacloprid FS seed treatment in potato cultivation.

In this paper, a complete optimization design verification process is proposed and a novel structure of connecting brackets is presented, solving the fatigue failure of chassis connecting brackets operating on harsh roads. First, an endurance road test and fatigue life analysis were applied to the truck equipped with the original brackets, verifying the fatigue damage of the structure. Based on the solid isotropic material with penalization method, a novel lightweight connecting bracket layout was obtained by using the method of moving asymptotes (MMA) for topology optimization under multiple working conditions with multiple performance constraints. Moreover, the derivatives of objective and constraint functions concerning design variables were applied for the MMA. Considering manufacturability and functionality, the improved model based on the topology optimization results was further optimized by size optimization. Finally, fatigue life analysis and an endurance road test were conducted using the optimal design. Compared with the original structure, the novel brackets showed better stiffness, strength and fatigue performance while reducing the total mass by 15.2%. The whole optimization and validation process can provide practical ideas and value for developing multi-performance suspensions in the pre-product development stage.

This paper investigates the impacts of trade openness on the allocation of human capital between public sector and private sector. Using a matched dataset of the 1% survey of China's population in 2005 and other city-level data, we find that individuals who reside in cities with higher degrees of trade openness are less likely to work in public sector, and this effect increases with educational attainment. We then employ a difference-in-differences model and a triple differences model based on the trade liberalization of China to alleviate endogeneity concerns, and finally come to a same conclusion. Further analysis reveals that trade openness triggers human capital reallocation by ameliorating business environment and raising the returns on human capital that is allocated to private sector.

Dissolved organic matter (DOM) in seawater, consisted of a complex mixture of compounds and accounted for about 90% of marine organic carbon, is an important part of the global carbon cycle and also a part of absolute salinity of seawater. As the components of DOM are non-ionized in seawater, electric conductivity measurement cannot observe its contribution to salinity, which could lead to measurement error in salinity. Salinity measurement based on optic refractive index could reveal contribution of all dissolved matters in seawater including both non-ionized and ionized components. In this paper, a comparative study of DOM contribution to the salinity measurement by optic refractive index method and electric conductivity method was carried out for the first time. Adding DOM, extracted from Aoshan Bay, Qingdao, China, into Chinese Standard Seawater, our experimental results showed an increase of optic refractive index at 1.19×10-4 ± 4×10-6 per 1g/kg of DOM, which corresponds to a practical salinity increase of 0.697 ± 0.036 PSU per 1 g/kg of DOM. While, the conductivity of seawater measured by a conductivity-temperature sensor showed a decrease of 0.00065 ± 0.00008 mS/cm per 1 g/kg of DOM, which corresponded to a decrease of salinity at 0.00052 ± 0.00007 PSU per 1 g/kg of DOM. By comparing the optic and electric measurement results, the contribution of non-conductive components in the dissolved organic matters to salinity could be distinguished, which has great significance for the measurement of absolute salinity, global carbon cycle etc.

In view of the defects in the previous detection of cuaminosulfate, which only focused on the analysis of copper ions, there is currently no analysis method available to determine the actual state of cuaminosulfate as chelated or bound. In order to investigate the dissipation and terminal residues in soil and watermelon of cuaminosulfate for food safety and environmental risk, a highly effective technique was developed to detect cuaminosulfate residues in watermelon and soil, and field experiments were conducted in China. After single-factor experiments, residual cuaminosulfate in samples was extracted by pure water, purified using a liquid–liquid approach combined with a dispersive solid-phase extraction, and detected by liquid chromatography tandem mass spectrometry (LC-MS/MS). The Box–Behnken design (BBD) study was used to find the optimal solutions for the time of liquid–liquid purification, the amount of extraction solvent, and the amounts of cleanup sorbents for the analytical method. The average recovery of the method was in the range of 80.0% to 101.1%, the average relative standard deviation (RSD) was 5.3–9.9%, and the detection limit was lower than 0.05 mg/kg. The BBD study not only improved the extraction rate of the method, but also saved time and was operated easily. The final residues of cuaminosulfate in watermelon at different sampling intervals were all lower than 0.05 mg/kg under field conditions. The cuaminosulfate in soils dissipated following exponential kinetics, with half-life values in the range of 9.39 to 12.58 days, which varied by different locations. Based on the validated method, food safety residues and soil residues can be determined rapidly and accurately.

N-doped biochar is widely used for activating persulfate to degrade organic pollutants. Which type of N atom is the key factor for activation is still unclear and needs to be further explored and analyzed. In this study, four kinds of biochar were prepared using urea and rice husk as precursors, and tested for the catalytic degradation of dimethomorph. Increasing the nitrogen doping level caused the catalytic removal efficiency of dimethomorph in the presence of peroxymonosulfate increased from 16.6% to 86.8%. A correlation analysis showed that the ability of N-doped biochar to activate PMS is mainly related to the content of pyrrole N, graphite N and carbonyl and the degree of defects. In experiments on electron paramagnetic resonance and free radical suppression, the reactive species of SO4•-, 1O2,·OH and O2.− were detected, among which 1O2 was found to be the main agent in the nonradical pathway. The degradation pathways for dimethomorph were analyzed based on a total of 8 degradation products identified by high-performance liquid chromatography-time of flight mass spectrometry (HPLC-Q-TOFMS). The results of this study provide a fundamental basis for using agricultural waste to produce inexpensive and efficient nonmetal catalysts that are highly effective in reducing dimethomorph levels in agricultural lands.

Abstract Background Lung resident mesenchymal stem cells (LR-MSCs) play an important role in idiopathic pulmonary fibrosis (IPF) by transforming into myofibroblasts, thereby losing their repair ability. Evidence suggests that key proteins of multiple signaling pathways are involved in myofibroblast differentiation of LR-MSCs, such as β-Catenin and GLI family zinc finger 1 (GLI1). These proteins are regulated by SUMO (small ubiquitin-like modifier) modification, which is a post-translational modification that promotes protein degradation, while Sumo specific protein 1 (SENP1)-mediated deSUMOylation produces the opposite biological effects. Therefore, we speculated that SENP1 might be a potential target for treating pulmonary fibrosis by preventing the myofibroblast differentiation of LR-MSCs. Methods LR-MSCs were isolated from mice by using immunomagnetic beads. The extracted LR-MSCs were identified by flow cytometric analysis and multilineage differentiation assays. Lentivirus packaged shRNA silenced the expression of SENP1 in vitro and vivo. The silencing efficacy of SENP1 was verified by real-time quantitative PCR. The effect of down-regulated SENP1 on the myofibroblast differentiation of LR-MSCs was assessed by Immunofluorescence and Western blot. Immunoprecipitation was used to clarify that SENP1 was a key target for regulating the activity of multiple signaling pathways in the direction of LR-MSCs differentiation. LR-MSCs resident in the lung was analyzed with in vivo imaging system. HE and Masson staining was used to evaluate the therapeutic effect of LR-MSCs with SENP1 down-regulation on the lung of BLM mice. Results In this study, we found that the myofibroblast differentiation of LR-MSCs in IPF lung tissue was accompanied by enhanced SENP1-mediated deSUMOylation. The expression of SENP1 increased in LR-MSCs transition of bleomycin (BLM)-induced lung fibrosis. Interfering with expression of SENP1 inhibited the transformation of LR-MSCs into myofibroblasts in vitro and in vivo and restored their therapeutic effect in BLM lung fibrosis. In addition, activation of the WNT/β-Catenin and Hedgehog/GLI signaling pathways depends on SENP1-mediated deSUMOylation. Conclusions SENP1 might be a potential target to restore the repair function of LR-MSCs and treat pulmonary fibrosis. Video Abstract

Riptortus pedestris (Fabricius, 1775) (Hemiptera: Alydidae) is a major soybean pest in East Asia that can cause soybean staygreen syndrome. To date, no insecticides have been registered for the control of R. pedestris in China, and these insects are primarily controlled in the field through the application of broad-spectrum insecticides including lambda-cyhalothrin (LCT) and emamectin benzoate (EMB). Here, the lethal and sublethal effects of LCT and EMB on R. pedestris were comprehensively evaluated. LCT and EMB were both found to exhibit high levels of toxicity and concentration-dependent repellent effects for R. pedestris. The exposure of third instar nymphs from the F0 generation to LC30 concentrations of LCT and EMB resulted in a significant increase in the duration of nymph development and adult pre-oviposition period (APOP), together with reductions in fifth instar nymph and adult body weight, longevity, oviposition days, fecundity, vitellarium length, lateral oviduct diameter, and vitellogenin (Vg) gene expression as compared to control treatment. Strikingly, these suppressive effects were transmitted to the F1 generation, which similarly experienced the prolongation of preadult development and the preoviposition period (TPOP). Relative to control-treated populations, the F1 generation for these insecticide-treated groups also exhibited significant decreases in population parameter values. Overall, these data offer new insight into the impact that LCT and EMB treatment can have on R. pedestris, providing a valuable foundation for the application of these pesticides in the context of integrated pest management strategies aimed at soybean crop preservation.

The risks posed by chemicals in the environment are typically assessed on a substance-by-substance basis, often neglecting the effects of mixtures. This may lead to an underestimation of the actual risk. In our study, we investigated the effects of three commonly used pesticides—imidacloprid (IMI), cycloxaprid (CYC), and tebuconazole (TBZ)—both individually and in combination, using various biomarkers to assess their impact on daphnia. Our findings indicated that the order of toxicity, from highest to lowest, was TBZ, IMI, and CYC, as determined by acute toxicity as well as reproduction. The effects of the ITmix (IMI and TBZ) and CTmix (CYC and TBZ) combinations on immobilization and reproduction were evaluated by MIXTOX, revealing a higher risk of immobilization at low concentrations for ITmix. The effect on reproduction differed depending on the ration of pesticides in the mixture, with synergism observed, which may be caused mainly by IMI. However, CTmix showed antagonism for acute toxicity, with the effect on reproduction depending upon the composition of the mixture. The response surface also exhibited a switch between antagonism and synergism. Additionally, the pesticides extended the body length and inhibited the development period. The activities of superoxide dismutase (SOD) and catalase (CAT) content was also significantly induced at different dosage points in both the single and combination groups, indicating changes in the metabolic capabilities of detoxifying enzymes and target site sensitivity. These findings highlight the need for more attention to be focused on the effects of pesticide mixtures.

The nitrate concentration in seawater is an important parameter for marine environment monitoring, which is of great significance for the analysis of seawater ecosystems. In this paper, a novel nitrate measurement system based on a narrowband tunable ultraviolet light source and support vector regression (SVR)-based algorithm is proposed and demonstrated. The system is composed of a tunable light source module, an optical fiber splitter, a temperature control module, a spectrometer and a data processing module. By controlling the motorized rotation stage and motorized filter wheel, a continuous and automatic narrowband tunable deep ultraviolet (DUV) light source module is developed. Different seawater samples from Aoshan Bay (Qingdao, China), the Western Pacific, Sanggou Bay (Weihai, China) and the South China Sea with nitrate concentrations of 0- $102~\mu $ mol/L are measured by this system based on a narrowband tunable DUV light source and the results are compared with those of a broadband DUV light source system. The calculation model is established based on the SVR algorithm with/without temperature and salinity correction (TSC), and the prediction results are compared with those of the in situ ultraviolet spectrophotometry (ISUS) algorithm. The results show that the method based on a narrowband tunable light source system and the TSC-SVR algorithm has the best performance in predicting the nitrate concentration, where the root mean squared error (RMSE) decreased by 29.16% (from 1.20 to $0.85~\mu $ mol/L) compared with the results of the broadband light source system, and the error range is from −3.01 to $2.99~\mu $ mol/L. The proposed method in this paper has the potential to provide more accurate measurements in marine environment monitoring.

Abstract A metal-clad planar polymer waveguide refractive index sensor based on epoxy (EPO) polymer materials by using light intensity interrogation at 850 nm is designed. The polymethyl methacrylate (PMMA) material is deployed as the low refractive index (RI) buffer layer in order to better couple the optical guided mode and the surface plasmon polaritons (SPP) mode for working in water environment. The effects of the gold film thickness, PMMA buffer layer thickness, waveguide layer thickness, waveguide width, and gold length on the sensor sensing characteristics have been comprehensively studied. Simulation results demonstrate that the normalized transmission increases quasi-linearly with the increment of RI of the analyte from 1.33 to 1.46. The sensitivity is 491.5 dB/RIU, corresponding to a high RI resolution of 2.6×10−9 RIU. The designed SPP-based optical waveguide sensor is low-cost, wide-range, and high-precision, and has a broad application prospect in biochemical sensing with merits of miniaturization, flexibility, and multiplexing.

Abstract A waveguide coupled surface plasmon sensor for detection of liquid with high refractive index (RI) is designed based on polymer materials. The effects of variation of the thickness of the Au film, polymethyl methacrylate (PMMA) buffer, and waveguide layer on the sensing performance of the waveguide are comprehensively investigated by using the finite difference method. Numerical simulations show that a thinner gold film gives rise to a more sensitive structure, while the variation of the thickness of the PMMA buffer and waveguide layer has a little effect on the sensitivity. For liquid with high RI, the sensitivity of the sensor increases significantly. When RI of liquid to be measured increases from 1.45 to 1.52, the sensitivity is as high as 4518.14nm/RIU, and a high figure of merit of 114.07 is obtained. The waveguide coupled surface plasmon RI sensor shows potential applications in the fields of environment, industry, and agriculture sensing with the merits of compact size, low cost, and high integration density.

We developed an extensible LED-induced fluorescence detection module with a highly integrated and ultra-compact structure. A target-oriented design methodology was used to demonstrate the module’s optimal design. Lucigenin solution was used as a test sample in evaluation trials to demonstrate the module’s quantitative fluorescence detection capability. Results showed that the integrated module has an outstanding linear response in the range of 0–1 μmol·L−1, with sensitivity and limit of detection (LOD) of 0.1692 V/μmol·L−1 and 0.03 μmol·L−1, respectively. Statistical analyses showed that our integrated module has extremely high repeatability and accuracy, i.e., the values of Pearson’s correlation coefficient and root-mean-square error exceeded 0.9995 and 1.8‰, respectively. More importantly, the integrated module possesses favorable extensibility and can realize on-demand rapid fluorescence-signal detection of other targets using appropriate parameter combinations. This module offers new opportunities for reliable, cost-effective and easy-to-use fluorescence-signal detection, especially in resource-constrained fluorescence detection applications.

An integrated interferometric fiber optic velocimetry sensor has been proposed and demonstrated at the central wavelength of 638 nm. The sensor is based on the principle of two laser-beams’ interference. The light signal scattered from the particles or vapor is demodulated to measure the water surface velocity and water vapor velocity. Three velocity measurement experiments are carried out to measure the velocity, and the experimental data shows that the velocity increases linearly in the range of 4 mm·s−1 to 100 mm·s−1, with a slope of linear fitting curve of 0.99777 and the R-Square of 1.00000. The velocity calculated from frequency shift fits well with the reference velocity. The maximum average relative error in the three velocity measurements is less than 2.5%. In addition, the maximum speed of 4.398 m·s−1 is confirmed in the rotating disk calibration experiment, which expands the sensor’s velocity measurement range. To solve the problem that it is difficult to directly measure the velocity of small-scale water surface flow velocity, especially from the aspect of the low velocity of air-water surface, the interferometric fiber optic sensor can be applied to the measurement of water surface velocity and wind velocity on the water surface.

With the acceleration of the process of agricultural modernization, many pesticides (insecticides, fungicides, and herbicides) are applied to the field and finally brought into the soils, causing serious damage to the environment. The problem of pesticide pollution has become increasingly prominent. This has highlighted the urgent need for effective and efficient remediation treatment technology for pesticide-contaminated soils. Biochar has a high specific surface area, high porosity, and strong adsorption capacity, making it a soil amendment agent and carbon fixation agent that can improve soil health and enhance adsorption capacity for pesticides to remediate contaminated soils. Recently, efforts have been made to enhance the physicochemical and adsorption properties of biochar by preparing modified biochar, and it has been developed to expand the application of biochar. Specifically, the following aspects were reviewed and discussed: (i) source and modification methods of biochar for pesticide remediation; (ii) the effect of biochar on the environmental fate of remediating pesticides; (iii) the effect of biochar on pesticide-contaminated soils; and (iv) potential problems for the large-scale promotion and application of biochar remediation of pesticides. In conclusion, this review may serve as a reference and guide for pesticide remediation, hence reducing the environmental concerns associated with pesticides in soil.

Given the key role of bees as indicators for environmental assessment, residues in bees and bee products have attracted great interest. In this regard, an improved, highly sensitive method for quantifying the insecticide pyriproxyfen and its four metabolites (4′-OH-Pyr, DPH-Pyr, 2-OH-PY, 4′-OH-POP) in honeybees, larvae, and bee products (honey, pollen, royal jelly and wax) should be established. For this purpose, we used ultra-performance liquid chromatography coupled with triple-quadrupole mass spectrometry for rapid quantification (≤5 min). Recoveries for various matrices ranged from 73.77% to 114.97%, with satisfactory intra-day and inter-day precision (relative standard deviations of 0.03–8.61% and 0.10–7.25%, respectively). The results demonstrated excellent linearity (R2 > 0.9903) with a limit of quantification of 1 μg/kg for six different matrices. We collected and analyzed 597 samples (honey, bees and wax) from four major beekeeping areas in China. Only 47 of these samples contained residues of pyriproxyfen and two of its metabolites (2-OH-PY, 4′-OH-Pyr), and high levels of contamination were found in bee samples (2–739 μg/kg), with substantive accumulation in wax (levels were 9.49% higher than in other samples). The result demonstrate that the method provides a reliable and convenient means of monitoring pyriproxyfen and its metabolites in bee products for better product quality, human health, and international commercial competition and also lays a foundation for risk assessment of potential pyriproxyfen contamination in China.

Due to its high persistence in soil, oxyfluorfen has negative effects on environmental and human health. To reduce soil contamination and impacts on non-target organisms, biochar is introduced into soils to immobilize and sequestrate oxyfluorfen as a remediation practice. Three types of soils common in China were selected and biochar (rice hull, BCR) was added to investigate the desorption and bioavailability of oxyfluorfen after aging BCR for 0, 1, 3, and 6 months. Four chemical extraction methods were used to predict oxyfluorfen bioavailability. Results indicated that after addition of 0.5–2% unaged BCR, the desorption values of oxyfluorfen increased from 64–119 to 176–920 (μg/g)/(mg/L)n in the three soils compared with unamended soil. The bioaccumulation factor (BCF) values of oxyfluorfen in earthworms decreased from 0.80–1.7 to 0.10–1.56 after BCR addition. However, the desorption values decreased from 170–868 to 144–701 (μg/g)/(mg/L)n after aging. The bioavailability of oxyfluorfen in earthworms also increased after the aging treatments, while the BCF was still lower than with unaged BCR. The reduced BCF indicated lower exposure risk of oxyfluorfen to earthworms after amendment with biochar, even after aging 6 months. The bioavailability after extraction by Tenax showed a high linear correlation with uptake in earthworms, even after the 6-month aging treatment (R2 > 0.80). Consequently, BCR could be a practical method to remediate contaminated soil and the 6h Tenax method could be a sensitive and feasible tool to assess the bioavailability of oxyfluorfen in soil.

In this paper, we review the characteristics of critical wavelength (CWL)-existed fiber-optic Mach–Zehnder interferometers (MZIs), including special few-mode fibers and microfibers, and their sensing applications in physical, chemical, and marine fields. Owing to the existence of CWL in the transmission spectra, the in-line MZIs show some specific characteristics. The closer the peak/dip wavelength to the CWL, the larger the wavelength shift or the related sensitivity when the interferometer is under testing. Meanwhile, CWL shifts monotonically with the variations in measurands, such as temperature (in the air or seawater), axial strain, water pressure, surrounding refractive index, etc., when they are applied to the sensing fibers. These characteristics of the CWL-existed in-line MZIs make them appealing solutions for fabricating various interferometric sensors, with the advantages of large measurement range, high sensitivity, multiparameter sensing, etc. Theoretical and experimental studies on the properties of the CWL-existed in-line MZIs are reviewed and discussed in this paper.

Orthopaedic implants are applied daily in our orthopaedic clinics for treatment of musculoskeletal injuries, especially for bone fracture fixation. To realise the multiple functions of orthopaedic implants, hybrid system that contains several different materials or parts have also been designed for application, such as prosthesis for total hip arthroplasty. Fixation of osteoporotic fracture is challenging as the current metal implants made of stainless steel or titanium that are rather rigid and bioinert, which are not favourable for enhancing fracture healing and subsequent remodelling. Magnesium (Mg) and its alloys are reported to possess good biocompatibility, biodegradability and osteopromotive effects during its in vivo degradation and now tested as a new generation of degradable metallic biomaterials. Several recent clinical studies reported the Mg-based screws for bone fixation, although the history of testing Mg as fixation implant was documented more than 100 years ago. Truthfully, Mg has its limitations as fixation implant, especially when applied at load-bearing sites because of rather rapid degradation. Currently developed Mg-based implants have only been designed for application at less or non–loading-bearing skeletal site(s). Therefore, after years research and development, the authors propose an innovative hybrid fixation system with parts composed of Mg and titanium or stainless steel to maximise the biological benefits of Mg; titanium or stainless steel in this hybrid system can provide enough mechanical support for fractures at load-bearing site(s) while Mg promotes the fracture healing through novel mechanisms during its degradation, especially in patients with osteoporosis and other metabolic disorders that are unfavourable conditions for fracture healing. This hybrid fixation strategy is designed to effectively enhance the osteoporotic fracture healing and may potentially also reduce the refracture rate.The translational potential of this article: This article systemically reviewed the combination utility of different metallic implants in orthopaedic applications. It will do great contribution to the further development of internal orthopaedic implants for fracture fixation. Meanwhile, it also introduced a titanium–magnesium hybrid fixation system as an alternative fixation strategy, especially for osteoporotic patients. Keywords: Fracture repair, Hybrid fixation system, Magnesium, Orthopaedic implants

Compact high-performance electro-optic (EO) modulators are key elements for optical communications. An electro-absorption modulator is theoretically designed. Due to the introduction of graphene film over the silicon slot waveguide, the modulation efficiency is strongly improved. The effect of waveguide dimensions, dielectric insulator thickness, and carrier mobility on performances of the proposed EO modulator have been comprehensively investigated. For the 120-μm-long graphene-on-silicon waveguide modulator, the extinction ratio 28 dB and insertion loss 1.28 dB can be obtained at 1550 nm when drive voltage is 1.91 and 0.59 V, respectively. The 3 dB bandwidth of 117 GHz can be obtained at a small power consumption of 212 fJ/bit. The proposed modulator possesses a high figure-of-merit of 20.5. Its benefits of small size, power saving, and process compatible promises possible applications in on-chip signal processing.

Nowadays, it is still a challenge for commercial nitrate sensors to meet the requirement of high accuracy in a complex water. Based on deep-ultraviolet spectral analysis and a regression algorithm, a different measuring method for obtaining the concentration of nitrate in seawater is proposed in this paper. The system consists of a deuterium lamp, an optical fiber splitter module, a reflection probe, temperature and salinity sensors, and a deep-ultraviolet spectrometer. The regression model based on weighted average kernel partial least squares (WA-KPLS) algorithm together with corrections for temperature and salinity (TSC) is established. After that, the seawater samples from Western Pacific and Aoshan Bay in Qingdao, China with the addition of various nitrate concentrations are studied to verify the reliability and accuracy of the method. The results show that the TSC-WA-KPLS algorithm shows the best results when compared against the multiple linear regression (MLR) and ISUS (in situ ultraviolet spectrophotometer) algorithms in the temperatures range of 4–25 °C, with RMSEP of 0.67 µmol/L for Aoshan Bay seawater and 1.08 µmol/L for Western Pacific seawater. The method proposed in this paper is suitable for measuring the nitrate concentration in seawater with higher accuracy, which could find application in the development of in-situ and real-time nitrate sensors.

With significant improvements in living standards in China and the aging population that accompanies these improvements, the market demand for high-quality orthopaedic biomaterials for clinical applications is tremendous and growing rapidly. There are major efforts to promote cooperation between different scientific institutes with complementary strengths for the further development of the biomaterial industry in China to achieve the technological level of developed countries. An excellent example is that the Ministry of Science and Technology of the People's Republic of China (MOST; Beijing, China) established the Chinese National Engineering Research Centres (CNERCs), which serve as a major initiative in driving basic and applied technological research and development (R&D) in mainland China. To create a win-win situation with Hong Kong, the MOST and the Hong Kong Innovation and Technology Commission are jointly establishing the Hong Kong Branch of the CNERCs. Through an amicable arrangement, the Chinese University of Hong Kong (CUHK; Shatin, Hong Kong) and the Chinese National Engineering Research Centre for Biomaterials (i.e., Main Centre) in Chengdu, People's Republic of China have decided to apply to establish the Hong Kong Branch of the CNERC for Biomaterials at the CUHK. The effort in establishing the Hong Kong Branch of Biomaterials seeks to promote further collaboration with the Main Centre with the goals of promoting synergy and a win-win cooperation between mainland China and Hong Kong in scientific research, talent cultivation, clinically driven novel biomaterials product design, and preclinical and clinical testing. It will thus become a model for the successful collaboration between the Hong Kong research institutions and the mainland CNERCs in the area of biomaterials. Such initiatives will facilitate close collaboration in translational medicine associated with biomaterial development and application.

This study aims to evaluate the effect of adventure education programs on resilience enhancement among first-year undergraduate students. The researchers designed adventure education courses using a benefits-based management activity planning model. An analysis is conducted using quasi-experimental and pre- and post-test non-equivalent group designs. Participants are divided into two groups: an experimental group and a control group. The effects of the adventure education programs as a 72-hour intervention are studied using a resilience scale. The data analysis employs a paired t-test and a one-way ANCOVA. The experimental group reports higher scores than the control group on the resilience scale and two subscales, problem-solving and interpersonal interaction, and these results are statistically significant. Further, the experimental group shows marginal positive changes in the total resilience scale and its two subscales in terms of effect size. The designed adventure education programs positively affect resilience among university freshmen.

MoS2 quantum dots (QDs) functionalized g-C3N4 nanosheets (MoS2@CNNS) were prepared through a protonation-assisted ion exchange method, which were developed as a highly efficient biomimetic catalyst. Structural analysis revealed that uniformly-dispersed MoS2 QDs with controllable size and different loading amount grew in-situ on the surface of CNNS, forming close-contact MoS2@CNNS nanostructures and exhibiting distinct surface properties. Compared to MoS2 QDs and CNNS, the MoS2@CNNS nanocomposites exhibited a more than four times stronger peroxidase-like catalytic activity, which could catalyze the oxidation of 3,3’,5,5’-tetramethylbenzidine (TMB) in the presence of H2O2 to generate a blue oxide. Among the MoS2@CNNS nanocomposites, MoS2@CNNS(30) was verified to present the best intrinsic peroxidase-like performance, which could be attributed to the more negative potential and larger specific surface area. A simple, rapid and ultrasensitive system for colorimetric detection of H2O2 was thus successfully established based on MoS2@CNNS, displaying nice selectivity, reusability, and stability. The detection limit of H2O2 could reach as low as 0.02 μM. Furthermore, the kinetic and active species trapping experiments indicated the peroxidase-like catalytic mechanism of MoS2@CNNS. This work develops a novel, rapid, and ultrasensitive approach for visual assay of H2O2, which has a potential application prospect on clinical diagnosis and biomedical analysis.

In a recent attempt to crystallize a regulator of MexAB-OprM multi-drug efflux systems in Pseudomonas aeruginosa (NalD), we found that adding polyethylene glycol (PEG3350, Mw = 3,350 g/mol) into the protein solution increases the speed of NalD migration in gel electrophoresis, signaling a smaller hydrodynamic size. At first we conjectured that NalD was degraded unexpectedly by PEG; however, we found that there was no change in its molar mass by MALDI-TOF characterization. Moreover, we found that adding polyacrylic acid (PAA) into the solution mixture returned the NalD migration to its normal speed. Furthermore, our analytic ultracentrifugation and dynamic laser light scattering results directly reveal that NalD interacts with PEG so that individual NalD chains gradually shrink as more PEG chains are added in the range of 10-50 mg/mL. Size exclusion chromatography also confirms that the NalD chain shrinks in the presence of PEG. A combination of these results indicates that PEG3350 chains can complex with NalD to induce an intra-protein chain contraction, presumably via the formation of hydrogen bond between -C-O-C- on PEG and -COOH on NalD, resulting in a smaller hydrodynamic size (faster migration) and a higher apparent molar mass. Note that because the presence of PEG affects osmotic pressure, it is considered to be a precipitator of protein crystallization. Our current finding reveals that the interaction of PEG/protein may play a significant role in protein crystallization. The complexation potentially makes the protein chain segments less flexible, and consequently makes crystallization easier. Hopefully, our current results will stimulate further studies in this direction.

Poly(N-isopropylacrylamide) (PNIPAM)-based polymers and gels are widely known and studied for their thermoresponsive property. In the biomaterials category, they are regarded as a potential cell culture substrate, not only because of their biocompatibility, but also their special character of allowing controlled detachment of cells via temperature stimulus. Previous research about PNIPAM-based substrates mostly concentrated on their effects in cell adhesion and proliferation. In this study, however, we investigate the influence of the PNIPAM-based substrate on the differentiation capacity of stem cells. Especially, we choose P(NIPAM-AA) microgels as a culture dish coating and mesenchymal stem cells (MSCs) are cultured on top of the microgels. Interestingly, we find that the morphology of MSCs changes remarkably on a microgel-coated surface, from the original spindle form to a more stretched and elongated cell shape. Accompanied by the alternation in morphology, the expression of several osteogenesis-related genes is elevated even without inducing factors. In the presence of full osteogenic medium, MSCs on a microgel substrate show an enhancement in the expression level of osteopontin and alizarin red staining signals, indicating the physical property of substrate has a direct effect on MSCs differentiation.