Efficacy of a single Nd:YAG laser dose in reducing pain after mandibular third molar extraction: a prospective randomized controlled clinical trial.

The purpose is to explore the analgesic effect of a single Nd:YAG laser dose after mandibular third molar extraction. This was a prospective randomized controlled clinical trial. Subjects were enrolled according to the inclusion and exclusion criteria and randomly divided into the experimental and control groups. In the experimental group, the wound was irradiated with the Nd:YAG laser (wavelength, 1064 nm; output power, 1.5 W; energy density, 45 J/cm2; and power density, 1.5/cm2, pulsed mode) immediately after mandibular third molar extraction for 120 s (30 s at each site). In the control group, the laser working tip was placed near the extraction site but not activated. The primary outcome was the visual analog scale (VAS) pain scores in both groups at 2, 4, 12, 24, 48, and 72 h and 7 days after surgery. Secondary outcomes included wound healing scores and adverse reactions. The VAS score was significantly lower in the experimental group than in the control group at 2 and 4 h after surgery, while there was no significant difference in the VAS score between the two groups at 12, 24, or 48 h or 7 days after surgery. There were no significant differences in the wound healing scores between the two groups on postoperative day 7. No adverse reactions were observed in any of the laser-irradiated areas. A single Nd:YAG laser dose was effective in reducing pain at 2 and 4 h after mandibular third molar extraction. China Clinical Trial Registry: ChiCTR2000033870 (Registration Date: 2020-6-15).

Effect of 320-Row Computed Tomography Acquisition Technology on Coronary Computed Tomography Angiography-Derived Fractional Flow Reserve Based on Machine Learning: Systolic and Diastolic Scan Acquisition.

BACKGROUND: The aim of the study is to investigate the performance of coronary computed tomography angiography (CCTA)-derived fractional flow reserve (CT-FFR) in the same patient evaluated by different systolic and diastolic scans, aiming to explore whether 320-slice CT scanning acquisition protocol has an impact on CT-FFR value. METHODS: One hundred forty-six patients with suspected coronary artery stenosis who underwent CCTA examination were included into the study. The prospective electrocardiogram gated trigger sequence scan was performed and electrocardiogram editors selected 2 optimal phases of systolic phase (preset collection trigger at 25% of R-R interval) and diastolic phase (preset collection trigger at 75% of R-R interval) for reconstruction. The lowest CT-FFR value (the CT-FFR value at the distal end of each vessel) and the lesion CT-FFR value (at 2 cm distal to the stenosis) after coronary artery stenosis were calculated for each vessel. The difference of CT-FFR values between the 2 scanning techniques was compared using paired Wilcoxon signed-rank test. Pearson correlation value and Bland-Altman were performed to evaluate the consistency of CT-FFR values. RESULTS: A total of 366 coronary arteries from the remaining 122 patients were analyzed. There was no significant difference regarding the lowest CT-FFR values between systole phase and diastole phase across all vessels. In addition, there was no significant difference in the lesion CT-FFR value after coronary artery stenosis between systole phase and diastole phase across all vessels. The CT-FFR value between the 2 reconstruction techniques had excellent correlation and minimal bias in all groups. The correlation coefficient of the lesion CT-FFR values for left anterior descending branch, left circumflex branch, and right coronary artery were 0.86, 0.84, and 0.76, respectively. CONCLUSIONS: Coronary computed tomography angiography-derived fractional flow reserve based on artificial intelligence deep learning neural network has stable performance, is not affected by the acquisition phase technology of 320-slice CT scan, and has high consistency with the evaluation of hemodynamics after coronary artery stenosis.

Information infrastructure and greenhouse gas emission performance in urban China: A difference-in-differences analysis.

Owing to its network spillover effect, information infrastructure performs outstandingly in promoting economic growth and technological innovation, and has received widespread attention. However, the ecological performance of information infrastructure, especially its impact on greenhouse gas (GHG) emission performance, has been less studied. To investigate this issue, using panel data for 281 prefecture-level cities in China from 2003 to 2018, we treat the Broadband China policy as a quasi-natural experiment in information infrastructure, and conduct a difference-in-differences (DID) analysis. The results show that: (1) Information infrastructure significantly improves urban GHG emission performance. This conclusion holds even after controlling for pilot selection endogeneity, sampling bias, and other policy interference. (2) Technological innovation, industrial structure upgrading, factor allocation enhancement, and tertiary agglomeration are effective channels for information infrastructure to improve GHG emission performance. (3) The treatment effect varies with city size, digital economy level, and economic status. Specifically, information infrastructure exhibits significant emission reduction performance in cities with large size, advanced digital economy, and leading economic status, while the emission reduction effect drops in other cities. This study provides insights into the transition to a carbon-neutral manner for infrastructure in China and other developing countries.

A Predictive Model for Survival of Escherichia coli O157:H7 and Generic E. coli in Soil Amended with Untreated Animal Manure.

This study aimed at developing a predictive model that captures the influences of a variety of agricultural and environmental variables and is able to predict the concentrations of enteric bacteria in soil amended with untreated Biological Soil Amendments of Animal Origin (BSAAO) under dynamic conditions. We developed and validated a Random Forest model using data from a longitudinal field study conducted in mid-Atlantic United States investigating the survival of Escherichia coli O157:H7 and generic E. coli in soils amended with untreated dairy manure, horse manure, or poultry litter. Amendment type, days of rain since the previous sampling day, and soil moisture content were identified as the most influential agricultural and environmental variables impacting concentrations of viable E. coli O157:H7 and generic E. coli recovered from amended soils. Our model results also indicated that E. coli O157:H7 and generic E. coli declined at similar rates in amended soils under dynamic field conditions.The Random Forest model accurately predicted changes in viable E. coli concentrations over time under different agricultural and environmental conditions. Our model also accurately characterized the variability of E. coli concentration in amended soil over time by providing upper and lower prediction bound estimates. Cross-validation results indicated that our model can be potentially generalized to other geographic regions and incorporated into a risk assessment for evaluating the risks associated with application of untreated BSAAO. Our model can be validated for other regions and predictive performance also can be enhanced when data sets from additional geographic regions become available.

Reducing both radiation and contrast doses in coronary CT angiography in lean patients on a 16-cm wide-detector CT using 70 kVp and ASiR-V algorithm, in comparison with the conventional 100-kVp protocol.

OBJECTIVE: To investigate the value of prospectively ECG-triggered coronary CT angiography (CCTA) for lean patients with body mass index (BMI) ≤ 23 kg/m2 using 70 kVp and high-level volume-based adaptive statistical iterative reconstruction (ASiR-V) algorithm on a 16-cm wide-detector CT system for reducing both radiation and contrast doses in comparison with the conventional 100-kVp protocol. MATERIALS AND METHODS: Thirty patients (group A) were prospectively enrolled to undergo 70-kVp CCTA on a 16-cm wide-detector CT scanner with noise index (NI) of 36 HU and at weight-dependent contrast dose rate of 16 mg I/kg/s for 9-s injection. Images were reconstructed with 80% ASiR-V. Radiation dose, contrast dose, and image quality were statistically compared with 30 patients (group B) in database with matching BMI who underwent conventional 100-kVp CCTA with NI of 25 HU, and at 25 mg I/kg/s rate for 10-s injection and reconstructed with 60% ASiR-V. RESULTS: There was no significant difference in patient demographics between the two groups (all p > 0.05). The two groups also had similar mean CT values and contrast-noise ratio (CNR) and subjective image quality (all p > 0.05). However, group A with 70 kVp reduced the effective dose by 75.3% compared with group B (0.43 ± 0.20 mSv vs. 1.74 ± 1.01 mSv, p < 0.001), and required 42.4% less contrast dose than group B (22.46 ± 2.94 ml vs. 38.99 ± 5.10 ml, p < 0.001). CONCLUSIONS: Prospectively ECG-triggered CCTA using 70 kVp and high-level ASiR-V on a 16-cm wide-detector CT system provides diagnostic images with substantial reduction in both radiation and contrast doses for patients with BMI ≤ 23 kg/m2 compared to the conventional 100-kVp protocol. KEY POINTS: • 70-kVp CCTA produces excellent images at sub-millisievert radiation. • 70-kVp CCTA reduces both radiation and contrast doses over conventional protocol. • Achieving low-dose CCTA with combined low kVp and high-level ASIR-V.

Triple-rule-out CT angiography using two axial scans with 16 cm wide-detector for radiation dose reduction.

OBJECTIVE: To explore the use of two consecutive axial scans in triple-rule-out (TRO) examination on a 16 cm wide-detector CT for radiation dose reduction. MATERIALS AND METHODS: Sixty TRO patients were assigned to either study group (Group A, n = 30) or control group (Group B, n = 30). Group A used a two-phasic contrast injection: 25mgI/kg/s for 12 s in 1st and at 3.0 ml/s injection rate for 7 s in 2nd phase. The pulmonary artery, coronary artery and aorta were scanned in succession with two axial scans using smart-coverage technique. Group B used the conventional protocol of scanning pulmonary arteries first in helical, followed by coronary arteries in axial and aorta in helical mode with contrast injection of 25mgI/kg/s for 14 s. All images were reconstructed with 80% ASIR-V. The qualitative and quantitative image assessment and effective dose of the two groups were statistically compared. RESULTS: The demographic data and quantitative measurements and qualitative image scores between the two groups were statistically the same (p > 0.05). However, Group A reduced radiation dose by 52% (2.67 ± 0.98 mSv vs. 5.65 ± 1.37 mSv) (p < 0.001). CONCLUSION: Using two consecutive axial scans in triple-rule-out on a 16 cm wide-detector CT reduces radiation dose while maintaining image quality compared with the conventional TRO protocol. KEY POINTS: • Triple-rule-out can be performed with two-axial scans on a wide-detector CT system. • TRO with two-axial scans maintain image quality compared with conventional protocol. • TRO with two-axial scans reduces 52% radiation dose over conventional protocol.

The Value of 16-cm Wide-Detector Computed Tomography in Coronary Computed Tomography Angiography for Patients With High Heart Rate Variability.

OBJECTIVE: The aim of this study was to investigate radiation dose and image quality of coronary computed tomography (CT) angiography (CCTA) for patients with high heart rate variability (HRv) using 16-cm wide-detector CT scanner. METHODS: One hundred sixty-six patients with uncontrolled heart rate underwent CCTA on a 16-cm wide-detector CT system and were divided into 2 groups based on their HRv for analysis: group A (n = 95, HRv ≤10 beats/min [bpm]) and group B (n = 71, HRv >10 bpm). Images in both groups were reconstructed with motion correction algorithm. Subjective and objective image qualities were analyzed. RESULTS: There were no significant differences in age, body mass index, and heart rate (68.1 ± 11.4 vs 67.6 ± 12.3 bpm) between the 2 groups (P > 0.05). However, group B had significantly higher HRv than group A (33.5 ± 24.4 vs 7.8 ± 1.2 bpm, P < 0.001). All images were acceptable for clinical diagnosis. Compared with group A, image quality scores in group B decreased slightly (4.1 ± 0.5 vs 4.0 ± 0.6). However, the difference was not statistically significant. The mean effective doses were both relatively low at 2.2 ± 1.1 mSv in group A and 2.6 ± 1.4 mSv in group B. CONCLUSIONS: Single-heartbeat free-breathing CCTA can be performed for patients with high HRv using 16-cm wide-detector CT scanner to achieve diagnostic image quality with low radiation dose.

A Mathematical Model for Pathogen Cross-Contamination Dynamics during the Postharvest Processing of Leafy Greens.

We developed a probabilistic mathematical model for the postharvest processing of leafy greens focusing on Escherichia coli O157:H7 contamination of fresh-cut romaine lettuce as the case study. Our model can (i) support the investigation of cross-contamination scenarios, and (ii) evaluate and compare different risk mitigation options. We used an agent-based modeling framework to predict the pathogen prevalence and levels in bags of fresh-cut lettuce and quantify spread of E. coli O157:H7 from contaminated lettuce to surface areas of processing equipment. Using an unbalanced factorial design, we were able to propagate combinations of random values assigned to model inputs through different processing steps and ranked statistically significant inputs with respect to their impacts on selected model outputs. Results indicated that whether contamination originated on incoming lettuce heads or on the surface areas of processing equipment, pathogen prevalence among bags of fresh-cut lettuce and batches was most significantly impacted by the level of free chlorine in the flume tank and frequency of replacing the wash water inside the tank. Pathogen levels in bags of fresh-cut lettuce were most significantly influenced by the initial levels of contamination on incoming lettuce heads or surface areas of processing equipment. The influence of surface contamination on pathogen prevalence or levels in fresh-cut bags depended on the location of that surface relative to the flume tank. This study demonstrates that developing a flexible yet mathematically rigorous modeling tool, a "virtual laboratory," can provide valuable insights into the effectiveness of individual and combined risk mitigation options.

Risk Assessment of Salmonellosis from Consumption of Alfalfa Sprouts and Evaluation of the Public Health Impact of Sprout Seed Treatment and Spent Irrigation Water Testing.

We developed a risk assessment of human salmonellosis associated with consumption of alfalfa sprouts in the United States to evaluate the public health impact of applying treatments to seeds (0-5-log10 reduction in Salmonella) and testing spent irrigation water (SIW) during production. The risk model considered variability and uncertainty in Salmonella contamination in seeds, Salmonella growth and spread during sprout production, sprout consumption, and Salmonella dose response. Based on an estimated prevalence of 2.35% for 6.8 kg seed batches and without interventions, the model predicted 76,600 (95% confidence interval (CI) 15,400-248,000) cases/year. Risk reduction (by 5- to 7-fold) predicted from a 1-log10 seed treatment alone was comparable to SIW testing alone, and each additional 1-log10 seed treatment was predicted to provide a greater risk reduction than SIW testing. A 3-log10 or a 5-log10 seed treatment reduced the predicted cases/year to 139 (95% CI 33-448) or 1.4 (95% CI <1-4.5), respectively. Combined with SIW testing, a 3-log10 or 5-log10 seed treatment reduced the cases/year to 45 (95% CI 10-146) or <1 (95% CI <1-1.5), respectively. If the SIW coverage was less complete (i.e., less representative), a smaller risk reduction was predicted, e.g., a combined 3-log10 seed treatment and SIW testing with 20% coverage resulted in an estimated 92 (95% CI 22-298) cases/year. Analysis of alternative scenarios using different assumptions for key model inputs showed that the predicted relative risk reductions are robust. This risk assessment provides a comprehensive approach for evaluating the public health impact of various interventions in a sprout production system.

Duck tembusu virus and its envelope protein induce programmed cell death.

The cytopathic effect produced in cells infected with duck tembusu virus (DTMUV) suggests that this emerging virus may induce apoptosis in primary cultures of duck embryo fibroblasts (DEF). Here, we present evidence that DTMUV infection of cultured cells activates apoptosis and that the ability of DTMUV to induce apoptosis is not restricted to cell type because DTMUV-induced apoptosis in duck and mammalian host cells. We further investigated which viral components induce apoptosis in DTMUV-infected host cells. The major envelope glycoprotein (E) was investigated for its apoptotic activities in expressed cells. Transient expression of the E protein alone triggered apoptosis in DEF, Vero, and BHK cells. Expression of the E protein resulted in activation of caspase-3-like proteases in cultured cells. These results indicate that infection of cells with DTMUV or expression of DTMUV E protein alone induces apoptosis, providing the basis for future to define the molecules that play key roles in the fate of DTMUV-infected cells.

Modeling number of bacteria per food unit in comparison to bacterial concentration in quantitative risk assessment: impact on risk estimates.

When developing quantitative risk assessment models, a fundamental consideration for risk assessors is to decide whether to evaluate changes in bacterial levels in terms of concentrations or in terms of bacterial numbers. Although modeling bacteria in terms of integer numbers may be regarded as a more intuitive and rigorous choice, modeling bacterial concentrations is more popular as it is generally less mathematically complex. We tested three different modeling approaches in a simulation study. The first approach considered bacterial concentrations; the second considered the number of bacteria in contaminated units, and the third considered the expected number of bacteria in contaminated units. Simulation results indicate that modeling concentrations tends to overestimate risk compared to modeling the number of bacteria. A sensitivity analysis using a regression tree suggests that processes which include drastic scenarios consisting of combinations of large bacterial inactivation followed by large bacterial growth frequently lead to a >10-fold overestimation of the average risk when modeling concentrations as opposed to bacterial numbers. Alternatively, the approach of modeling the expected number of bacteria in positive units generates results similar to the second method and is easier to use, thus potentially representing a promising compromise.

Listeria monocytogenes dose response revisited--incorporating adjustments for variability in strain virulence and host susceptibility.

Evaluations of Listeria monocytogenes dose-response relationships are crucially important for risk assessment and risk management, but are complicated by considerable variability across population subgroups and L. monocytogenes strains. Despite difficulties associated with the collection of adequate data from outbreak investigations or sporadic cases, the limitations of currently available animal models, and the inability to conduct human volunteer studies, some of the available data now allow refinements of the well-established exponential L. monocytogenes dose response to more adequately represent extremely susceptible population subgroups and highly virulent L. monocytogenes strains. Here, a model incorporating adjustments for variability in L. monocytogenes strain virulence and host susceptibility was derived for 11 population subgroups with similar underlying comorbidities using data from multiple sources, including human surveillance and food survey data. In light of the unique inherent properties of L. monocytogenes dose response, a lognormal-Poisson dose-response model was chosen, and proved able to reconcile dose-response relationships developed based on surveillance data with outbreak data. This model was compared to a classical beta-Poisson dose-response model, which was insufficiently flexible for modeling the specific case of L. monocytogenes dose-response relationships, especially in outbreak situations. Overall, the modeling results suggest that most listeriosis cases are linked to the ingestion of food contaminated with medium to high concentrations of L. monocytogenes. While additional data are needed to refine the derived model and to better characterize and quantify the variability in L. monocytogenes strain virulence and individual host susceptibility, the framework derived here represents a promising approach to more adequately characterize the risk of listeriosis in highly susceptible population subgroups.

Optimization of Antifungal Extracts from Ficus hirta Fruits Using Response Surface Methodology and Antifungal Activity Tests.

The fruits of Ficus hirta (FH) display strong antifungal activity against Penicillium italicum and Penicillium digitatum. In order to optimize the extraction conditions of antifungal extracts from FH fruit, various extraction parameters, such as ethanol concentration, extraction time, solvent to solid ratio and temperature, were chosen to identify their effects on the diameters of inhibition zones (DIZs) against these two Penicillium molds. Response surface methodology (RSM) was applied to obtain the optimal combination of these parameters. Results showed that the optimal extraction parameters for maximum antifungal activity were: 90% (v/v) ethanol concentration, 65 min extraction time, 31 mL/g solvent to solid ratio and 51 °C temperature. Under the abovementioned extraction conditions, the experimental DIZs values obtained experimentally were 57.17 ± 0.75 and 39.33 ± 0.82 mm, which were very close to the values of 57.26 and 39.29 mm predicted by the model. Further, nine kinds of phytopathogens were tested in vitro to explore the antifungal activity of the FH extracts. It was found for the first time that the FH extracts showed significant inhibition on the growth of P. italicum, A. citri, P. vexans, P. cytosporella and P. digitatum.

A luminescent ionogel based on an europium(III)-coordinated carboxyl-functionalized ionic liquid and gelatin.

In this work, we report the preparation and luminescent properties of a novel luminescent ionogel consisting of a carboxyl-functionalized ionic liquid, Eu(3+) ions and gelatin. The obtained ionogel was investigated by FT-IR, SEM and photoluminescence spectroscopy. FT-IR spectra show that both the ionic liquid and the gelatin are coordinated to Eu(3+) ions through oxygen atoms. Luminescence data confirm that Eu(3+) ions are well-protected by the ionic liquid and gelatin from deleterious quenching interactions with water molecules.

XylR Overexpression in Escherichia coli Alleviated Transcriptional Repression by Arabinose and Enhanced Xylitol Bioproduction from Xylose Mother Liquor.

Xylitol is a polyol widely used in food, pharmaceuticals, and light industries. It is currently produced through the chemical catalytic hydrogenation of xylose and generates xylose mother liquor as a substantial byproduct in the procedure of xylose extraction. If xylose mother liquor could also be efficiently bioconverted to xylitol, the greenness and atom economy of xylitol production would be largely improved. However, xylose mother liquor contains a mixture of glucose, xylose, and arabinose, raising the issue of carbon catabolic repression in its utilization by microbial conversion. Targeting this challenge, the transcriptional activator XylR was overexpressed in a previously constructed xylitol-producing E. coli strain CPH. The resulting strain CPHR produced 16.61 g/L of xylitol in shake-flask cultures from the mixture of corn cob hydrolysate and xylose mother liquor (1:1, v/v) with a xylose conversion rate of 90.1%, which were 2.23 and 2.15 times higher than the starting strain, respectively. Furthermore, XylR overexpression upregulated the expression levels of xylE, xylF, xylG, and xylH genes by 2.08-2.72 times in arabinose-containing medium, suggesting the alleviation of transcriptional repression of xylose transport genes by arabinose. This work lays the foundation for xylitol bioproduction from xylose mother liquor.

Age-effects of sport education model on basic psychological needs and intrinsic motivation of adolescent students: A systematic review and meta-analysis.

OBJECTIVE: This study explores the age effects of the sport education model(SEM) on the impact of basic psychological needs (autonomy, competence, relatedness) and intrinsic motivation (interest, enjoyment, satisfaction) among adolescent students. METHOD: Retrieval of relevant literature from PubMed, Web of Science, Scopus, and China National Knowledge Infrastructure (CNKI). The search period ranged from the starting year to January 7, 2024. Subsequently, literature screening, data extraction, and quality assessment will be conducted, and data analysis will be performed using "Review Manager 5.4" software. RESULT: Overall, SEM has a positive and statistically significant impact on the basic psychological needs (MD = 0.36,95% CI [0.22, 0.50]) and intrinsic motivation (MD = 0.75, 95% CI [0.58, 0.93]) of adolescent students (P<0.01). Subgroup analysis revealed age effects on the impact of SEM on the basic psychological needs of adolescent students: pre-peak height velocity (PRE-PHV) (MD = 0.39, 95% CI [0.23, 0.56], I2 = 45%, P<0.01), mid-peak height velocity (MID-PHV) (MD = 0.22, 95% CI [0.01, 0.42], I2 = 82%, P<0.05), post-peak height velocity (POST-PHV) (MD = 1.27, 95% CI [0.79, 1.74], I2 = 0%, P<0.01). Similarly, age effects were found for intrinsic motivation: MID-PHV (MD = 0.86, 95% CI [0.62, 1.11], I2 = 68%, P<0.01), POST-PHV (MD = 0.56, 95% CI [0.40, 0.72], I2 = 0%, P<0.01). CONCLUSION: The SEM is an effective approach to enhancing the basic psychological needs and intrinsic motivation of adolescent students. However, it exhibits age effects among students at different developmental stages. Specifically, in terms of enhancing basic psychological needs, the model has the greatest impact on POST-PHV students, followed by PRE-PHV students, while the improvement effect is relatively lower for MID-PHV students. The enhancement effect on intrinsic motivation diminishes with increasing age.

Modulatory effects of fermented Polygonatum cyrtonema Hua on immune homeostasis and gut integrity in a dextran-sulfate-sodium-induced colitis model.

The gut health-promoting properties of saponin-rich Polygonatum cyrtonema Hua (FP) fermented with Lactobacillus plantarum P9 were explored in a dextran sulfate sodium (DSS)-induced colitis mouse model. FP supplementation effectively inhibited DSS-induced physiological alteration and impaired immune responses by reducing the disease activity index (DAI) score and restoring the T helper (Th) 1/Th2 and regulatory T (Treg)/Th17 ratios. In addition, FP supplementation protected the gut barrier function against DSS-induced damage via upregulation of zonula occludens (ZO)-1 and occludin and downregulation of pro-inflammatory cytokines, including interleukin (IL)-1ß, tumor necrosis factor-α (TNF-α), IL-18, and the granulocyte-macrophage colony-stimulating factor (GM-CSF). This study further elucidated the potential mechanisms underlying the FP-mediated suppression of the plasticity of type 3 innate lymphoid cells (ILC3) and subsequent macrophage polarization. Therefore, the FP supplementation effectively restored mucosal immune homeostasis and enhanced gut integrity. In addition, it suppressed the growth of Escherichia-Shigella and Enterococcus and promoted the enrichment of probiotics and short-chain fatty acid-producing microbes, such as Romboutsia, Faecalibaculum, and Blautia. In conclusion, P. cyrtonema Hua fermented with L. plantarum P9 might be a promising dietary intervention to improve gut health by sustaining overall gut homeostasis and related gut integrity.

Enantiodivergent kinetic resolution of 4-substituted 1,2,3,4-tetrahydroquinolines employing amine oxidase.

Optically pure 1,2,3,4-tetrahydroquinolines (THQs) represent a class of important motifs in many natural products and pharmaceutical agents. While recent advances on redox biocatalysis have demonstrated the great potential of amine oxidases, all the transformations focused on 2-substituted THQs. The corresponding biocatalytic method for the preparation of chiral 4-substituted THQs is still challenging due to the poor activity and stereoselectivity of the available enzyme. Herein, we developed a biocatalytic kinetic resolution approach for enantiodivergent synthesis of 4-phenyl- or alkyl-substituted THQs. Through structure-guided protein engineering of cyclohexylamine oxidase derived from Brevibacterium oxidans IH-35 A (CHAO), the variant of CHAO (Y215H/Y214S) displayed improved specific activity toward model substrate 4-phenyl substituted THQ (0.14 U/mg, 13-fold higher than wild-type CHAO) with superior (R)-stereoselectivity (E > 200). Molecular dynamics simulations show that CHAO Y215H/Y214S allows a suitable substrate positioning in the expanded binding pocket to be facilely accessed, enabling enhanced activity and stereoselectivity. Furthermore, a series of 4-alkyl-substituted THQs can be transformed by CHAO Y215H/Y214S, affording R-isomers with good yields (up to 50 %) and excellent enantioselectivity (up to ee > 99 %). Interestingly, the monoamine oxidase from Pseudomonas fluorescens Pf0-1 (PfMAO1) with opposite enantioselectivity was also mined. Together, this system enriches the kinetic resolution methods for the synthesis of chiral THQs.

Complete genomic sequence of duck flavivirus from china.

We report here the complete genomic sequence of the Chinese duck flavivirus TA strain. This work is the first to document the complete genomic sequence of this previously unknown duck flavivirus strain. The sequence will help further relevant epidemiological studies and extend our general knowledge of flaviviruses.

High-Efficiency Adsorption of Cr(VI) and Mn(VII) from Wastewater by a Two-Dimensional Copper-Based Metal-Organic Framework.

Cr(VI) and Mn(VII) in industrial wastewater have certain toxicity, and they pose a threat to the environment and human health and safety. Metal-organic frameworks (MOFs) usually have rich adsorption sites and a large specific surface area. They can effectively adsorb Cr(VI) and Mn(VII) from wastewater. In this paper, a two-dimensional copper-based metal-organic framework, {[Cu·(4,4'-bpy)2·(H2O)]·2(NO3)·6(H2O)·(CH3OH)}n (1), is synthesized by hydrothermal synthesis. The structure of 1 is characterized by Fourier transform infrared (IR) spectroscopy, single-crystal X-ray diffraction, element analysis, and X-ray photoelectron spectroscopy (XPS). The results showed that 1 had a two-dimensional network structure, and the specific surface area of the nanostructure was 67.63 m2/g. The nanostructure of 1 could efficiently adsorb Cr(VI) and Mn(VII) from wastewater. The adsorption properties of Cr(VI) and Mn (VII) of 1 showed that the optimal concentration of both adsorbents was 0.2 g/L. It has good adsorption performance in the pH range 4-8. The adsorption performance is the best when pH is 7, which can reach 145 and 83 mg/g, respectively.