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The herbicidal activity of the fermentation broth, filtrate, and extracts of Bacillus altitudinisD30202 was evaluated against seed germination and seedling growth of wild oat (Avena fatuaL.). The bacterial culture filtrate exhibited greater inhibition of the wild oat weed than the fermentation broth. The filtrate was also extracted with organic solvents. The herbicidal potency of the extracts on the growth of wild oat plants was as follows: chloroform (100% inhibition of germination) > n‐butanol (93.8%) > ethyl acetate (66.7%) > petroleum ether (6.3%) > aqueous phase (2.1%); so the chloroform extract was evaluated further. It inhibited wild oat radicle growth by 100%, and plumule growth by 97.9%, while spraying young plants with a 5 mg/mL extract caused severe desiccation of the leaves, stalk wilting, and plant death. IC50values for inhibition of plumule and radicle growth and germination were 0.64–0.72 mg/mL. Scanning electron microscopy and transmission electron microscopy revealed changes in the microstructure of the leaves and root tips, and degradation of organelles following chloroform extract treatment. The 5 mg/mL extract had no adverse impact on the growth or health of highland barley (Hordeum vulgareL.), corn (Zea mays), and broad bean (Vicia fabaL.), indicating that this novel bioherbicide is suitable for control of wild oat weeds in the production of these food crops (while having a minor impact on the health of pea plants and being phytotoxic to wheat plants). Herbicidal potency of Bacillus altitudinisD30202 chloroform extract against wild oat exceeds broth/filtrate.Chloroform extract inhibits wild oat germination completely and early growth by over 98%.5 mg/mL extract spray desiccates and kills young oat by disrupting chloroplast and membrane structures.Novel bioherbicide has no adverse impact on growth of highland barley, corn, and broad bean.

Fluorochloridone (FLC) is a chiral herbicide that has four stereoisomers. This study systematically assessed the stereoselectivity of FLC to reveal the selective environmental behavior of its four isomers. Absolute configuration confirmation, evaluation of stereoselective bioactivity toward monocotyledonous and dicotyledonous weeds, toxicity to Danio rerio, and the stereoselective degradation in the potato system under field conditions of FLC were conducted. The four FLC stereoisomers were effectively separated on a superchiral S-AD column. The absolute configurations of the four stereoisomers of FLC were confirmed as (−)-(3S, 4S), (+)-(3S, 4R), (−)-(3R, 4S), and (+)-(3R, 4R)-FLC using single-crystal X-ray diffraction. The activities of the four stereoisomers were in the order of (−)-(3S, 4S)-FLC > (+)-(3R, 4R)-FLC > (+)-(3S, 4R)-FLC > (−)-(3R, 4S)-FLC, and the rate of selective degradation were in the order of (−)-(3R, 4S)-FLC > (+)-(3R, 4R)-FLC > (−)-(3S, 4R)-FLC > (+)-(3S, 4S)-FLC. The toxicity of the isomers were in the order of (−)-(3R, 4S)-FLC > (+)-(3R, 4R)-FLC > (−)-(3S, 4S)-FLC > (+)-(3S, 4R). Based on the results of bioactivity, toxicity, and degradation behavior assessments, the stereoisomer mixture containing (3R,4R)-FLC and (3S,4S)-FLC was concluded to be a better option than racemic FLC for increasing bioactivity and reducing usage.

To further promote the widely practical application of C–H activation, developing green and mild reaction conditions has invariably been the objective of researchers, especially when it comes to remote C–H activation reactions. Herein, we report a new cheap and powerful (n-Bu)4NNO3oxidant. This oxidant is efficient and universal for Pd(II)-catalyzed sp2and sp3C–H olefination and allows the reaction to be carried out at room temperature. Because of this, we attempted to make C–H functionalization more economical and environmentally benign.

This research aims at teaching solfeggio and ear training in college music and proposes a teaching method for college music note recognition that combines the musical instrument digital interface (MIDI) and hidden Markov models (HMM). The experiment showcases that after preprocessing the music frequency sample signal using HMM model, it achieves the target accuracy after 20 times of training. From the HMM transition probability matrix diagram estimated from all training data sets, it can be seen that the transition matrix is close to the diagonal matrix. This indicates its high transfer efficiency. This study compares the HMM model with the other two algorithms, and the results show that its accuracy rate is about 99.56%. The probability of insertion errors and elimination errors is 0.52% and 2.58%. This is superior to the other two algorithms. In summary, the HMM model proposed in the study has extremely strong performance in the teaching of music note feature recognition in universities and can provide better teaching methods.

Avena fatuaL. (wild oat) is one of the most harmful gramineous weeds that can affect the yield and quality of infiltrating crops. Bacillus altitudinisD30202 exhibits an excellent biocontrol activity against wild oat. To elucidate the biocontrol mechanisms of B. altitudinisD30202, the genome structure of this strain was assessed via whole-genome sequencing analysis. We predicted and analyzed secondary metabolite synthesis gene clusters to elucidate the mechanisms underlying the biocontrol of weeds. The whole-genome sequencing data indicated that B. altitudinisD30202 had the genome size and GC content of 3,777,154 bp and 41.32%, respectively, and 3809 coding genes were identified. Moreover, this strain could generate several compounds with bioherbicidal activity, including 4-hydroxy-3-methoxycinnamic acid and two indole derivatives. Bioinformatics prediction and comparative genomic analysis revealed that the strain had 6 secondary metabolite gene clusters. Furthermore, the taxonomic position of B. altitudinisD30202 was assessed, confirming its uniqueness and novelty within the Bacillusgenus. Comparative genomic analysis showed differences in gene distribution, suggesting potential adaptations to different environments. In conclusion, B. altitudinisD30202 possesses a genome with unique characteristics, encoding enzymes and pathways related to herbicidal potential and biocontrol. This study provides a reference basis for understanding the molecular mechanisms of weed inhibition.

Given that the global fleet of coal-fired power plants is mostly new, coal–biomass co-firing power plants with retrofitted carbon capture and storage (CBECCS) are regarded as a promising option for CO2emissions reduction. However, the effectiveness of CBECCS remains largely unexplored. Here we develop a comprehensive assessment framework featuring a macro power system combined with spatially explicit biomass sources, coal-fired units and geological storage sites. We apply this framework to investigate the spatiotemporal deployment of CBECCS in China. The results indicate that a transition to CBECCS in 2025 could supply 0.97 GtCO2yr–1sequestration potential, with 90% at a levelized cost between $30 and $50 tCO2–1. A higher CO2mitigation of 1.6 Gtyr–1could be achieved in 2040 by increasing the unit utilization hours, corresponding to a cumulative contribution of 41.2 GtCO2over the period 2025–2060. This study provides a useful reference for transforming coal-dominated power systems.

Traditional internal combustion engines (ICEs) have garnered considerable attention due to their high emissions and low efficiency issues. In this study, a novel ICE–fuel cell hybrid power system based on a single‐methanol fuel is proposed to address these concerns. The system utilizes methanol as fuel, directly supplying it to the methanol engine, and generates hydrogen for the fuel cell through methanol reforming technology. The structural design of the system fully exploits engine exhaust, first using waste heat for methanol reforming to produce hydrogen and then utilizing exhaust inertial potential energy to drive a dual turbocharging structure for air compression entering the fuel cell, thereby achieving self‐thermal balance. Thermodynamic analysis and cost evaluation indicate that the thermal efficiency of this system is improved by 8.34% compared to traditional diesel engine setups. Compared to engine‐fuel cell hybrid systems that do not utilize waste heat, the thermal efficiency is increased by 5.81%. In terms of economics, the cost of the methanol engine system is ≈.1466$ kW h−1$\left(\text{kW h}\right)^{- 1}$, which is 44.05% lower than the 0.262 $kW h−1$\left(\text{ kW h}\right)^{- 1}$fuel cost of traditional diesel engine systems. This study presents an innovative solution that significantly enhances thermal efficiency and offers economic advantages, providing a viable approach to address the low efficiency and high emissions issues of traditional ICEs. This study introduces a novel internal combustion engine–fuel cell hybrid power system based on single‐methanol fuel. The system design utilizes engine exhaust energy for methanol reforming to produce hydrogen and drive a dual turbocharger setup. Compared to conventional diesel engines, it achieves an 8.34% increase in thermal efficiency and reduces fuel costs by 44.05%.

ABSTRACTThis study investigated the inhibitory activity of Halobacillus trueperiS61 and its active extract on potato dry rot pathogens and aimed at contributing to biocontrol agent development during potato storage. Three kinds of pathogens were isolated as target pathogenic fungi from dry rot tubers and determined as Fusarium acuminatum(Qing 9A-2), Fusarium equisetai(Qing 9A-5-8) and Fusarium tricinctum(Qing 9A-1-1) by morphological and molecular identification. The strain Halobacillus trueperiS61 and its extract exhibited a higher inhibitory rate on both three pathogens (56.32–65.75 and 1.67–51.11%), notably the best suppression efficiency is presented in Halobacillus trueperiS61 and 40 mg/mL ethyl acetate extract. In terms of in vivo effects, both Halobacillus trueperiS61 and its ethyl acetate extract effectively reduced the decayed fruit and weight loss rate (0–20% and 7.59–16.56%) and enhanced the defensive enzymatic activities to improve resistance. In addition, strain S61 could be colonized on potato tubers, especially the highest amount of 1.55 × 107CFU/mL on fifth day for variety Xiazhai 65. Overall, Halobacillus trueperiS61 and its ethyl acetate extract could be considered as potential approach for biocontrol potato dry rot.

ABSTRACTIn order to isolated and identified the bacterial strains from wheat rhizosphere and evaluated the effect of different concentration of bacterial fermentation broth on the wild oats weed growth. This experiment carried out the separation and purification of dominant bacterial strains from the wheat rhizosphere soil, and performed the fermentation broth biological activity assessment by measured the seed germination and plant growth from 20 wheat varieties. The results had shown that the bacterial fermentation broth inhibits the growth of wild oat seedlings and plants to varying degrees, bacterial strains of X3, X4, X8, X12, X16 and X20 has certain level of inhibition activity and X20 has the highest herbicidal effectiveness. According to molecular biology identification, obtained superior bacterial strains X20 was Bacillusas potentially inhibitor for developing of bacterial-based bioherbicides for wild oats weed control management in the wheat field.

A trinomial tree model based on a real options approach was developed to evaluate the investment decisions on carbon capture, utilization, and storage (CCUS) retrofitted to the three main types of thermal power plants in China under the same power generation and CO2emissions levels. The plant types included pulverized coal (PC), integrated gasification combined cycle (IGCC), and natural gas combined cycle (NGCC) plants. We take into account a subsidy policy consistent with the 45Q tax credit of the U.S., as well as uncertainty factors, such as carbon price, technological progress, CO2geological storage paths, oil price, and electricity price. The results showed that the investment benefit of ordinary NGCC power plants is 93.04 million USD. This provides greater economic advantages than the other two plant types as their investment benefit is negative if the captured CO2was used for enhanced water recovery (EWR), even if 45Q subsidies are provided. Compared with NGCC + CCUS power plants, PC + CCUS and IGCC + CCUS power plants have more advantages in terms of economic benefits and emission reduction. The 45Q subsidy policy reduced the critical carbon price, which determines the decision to invest or not, by 30.14 USD t−1for the PC and IGCC power plants and by 15.24 USD t−1for the NGCC power plants. Nevertheless, only when the subsidy reaches at least 71.84 USD t−1and the period limit is canceled can all three types of power plants be motivated to invest in CCUS and used the capture CO2for EWR. Overall, the government should focus on the application of CCUS in coal-fired power plants (in addition to developing gas power generation), especially when CO2is used for enhanced oil recovery (EOR). The government could introduce fiscal policies, such as 45Q or stronger, to stimulate CCUS technology development in China.

The silica gel promoted straightforward remote para‐C−H hydroxylation of aryl‐urea derivatives under metal‐free mild conditions by using diacetoxyiodobenzene as oxidant has been developed. Replacing the Lewis acids with silica gel effectively improved the tolerance of functional groups and resulted in a wide range of target compounds with various substituents in moderate to excellent yields. Moreover, this transformation has been demonstrated that could more effectively and conveniently synthesize pharmaceutical and biomedical compounds which contain 4‐hydroxyarlyurea skeleton. A new methodfor the silica gel promoted straightforward remote para‐C‐H hydroxylation of aryl‐urea derivatives under metal‐free mild conditions by using diacetoxyiodobenzene as oxidant in moderate to good yields.

•Vacuum package combined with 0 °C storage did well in prolonging fillets’ shelf-life.•Shelf-life prediction models of fillets were developed with Arrhenius equations.•The TBA-based predicted shelf-life was shorter than the days predicted by TVB-N.•Predicted shelf-life based on TVB-N was in line with when fillets were unacceptable.•Predicted shelf-life based on TBA was in line with when fillets were not good.

Achieving high para-selective C–H functionalized products of benzoic acid derivatives using a designed template is still a daunting challenge because the carbonyl group also could coordinate with metal to activate the ortho-C–H bond. Herein, we report the ligand promoted high para-selective C–H olefination of benzoic acid derivatives; we screened a series of ligands increasing the ratio of p:others from 62:38 to 96:4. This work may find application in the construction of para-substituted benzoic acid derivatives.

Hepatocellular carcinoma (HCC) is one of most common and deadliest malignancies. Celastrol (Cel), a natural product derived from the Tripterygium wilfordiiplant, has been extensively researched for its potential effectiveness in fighting cancer. However, its clinical application has been hindered by the unclear mechanism of action. Here, we used chemical proteomics to identify the direct targets of Cel and enhanced its targetability and anti-tumor capacity by developing a Cel-based liposomes in HCC. We demonstrated that Cel selectively targets the voltage-dependent anion channel 2 (VDAC2). Cel directly binds to the cysteine residues of VDAC2, and induces cytochrome C release via dysregulating VDAC2-mediated mitochondrial permeability transition pore (mPTP) function. We further found that Cel induces ROS-mediated ferroptosis and apoptosis in HCC cells. Moreover, coencapsulation of Cel into alkyl glucoside-modified liposomes (AGCL) improved its antitumor efficacy and minimized its side effects. AGCL has been shown to effectively suppress the proliferation of tumor cells. In a xenograft nude mice experiment, AGCL significantly inhibited tumor growth and promoted apoptosis. Our findings reveal that Cel directly targets VDAC2 to induce mitochondria-dependent cell death, while the Cel liposomes enhance its targetability and reduces side effects. Overall, Cel shows promise as a therapeutic agent for HCC.

Description

ABSTRACTA Western immunoblot assay for confirmatory serodiagnosis of severe acute respiratory syndrome (SARS) was developed utilizing viral lysate antigens combined with a recombinant nucleocapsid protein, GST-N (glutathione S-transferase-nucleocapsid) of the SARS coronavirus (SARS-CoV). The viral lysate antigens were separated by electrophoresis and transblotted onto nitrocellulose membranes. The resultant membrane was subsequently added with the GST-N recombinant protein at a specific location. The positions of bands corresponding to some of the structural proteins immobilized on the membrane were then located and verified with mouse or rabbit antisera specific to the respective proteins. The Western immunoblot assay was able to detect antibodies to SARS-CoV in all 40 serum specimens from SARS patients and differentiate the SARS-positive samples from those of the healthy donor or non-SARS patient controls (150 samples) when set criteria were followed. In addition, when the immunoblot was used to test samples considered falsely positive by an in-house-developed SARS-specific enzyme-linked immunosorbent assay, band patterns different from those with samples from SARS patients were obtained.

ABSTRACTA new coronavirus (severe acute respiratory syndrome coronavirus [SARS-CoV]) has been identified to be the etiological agent of severe acute respiratory syndrome. Given the highly contagious and acute nature of the disease, there is an urgent need for the development of diagnostic assays that can detect SARS-CoV infection. For determination of which of the viral proteins encoded by the SARS-CoV genome may be exploited as diagnostic antigens for serological assays, the viral proteins were expressed individually in mammalian and/or bacterial cells and tested for reactivity with sera from SARS-CoV-infected patients by Western blot analysis. A total of 81 sera, including 67 from convalescent patients and seven pairs from two time points of infection, were analyzed, and all showed immunoreactivity towards the nucleocapsid protein (N). Sera from some of the patients also showed immunoreactivity to U274 (59 of 81 [73%]), a protein that is unique to SARS-CoV. In addition, all of the convalescent-phase sera showed immunoreactivity to the spike (S) protein when analyzed by an immunofluorescence method utilizing mammalian cells stably expressing S. However, samples from the acute phase (2 to 9 days after the onset of illness) did not react with S, suggesting that antibodies to N may appear earlier than antibodies to S. Alternatively, this could be due to the difference in the sensitivities of the two methods. The immunoreactivities to these recombinant viral proteins are highly specific, as sera from 100 healthy donors did not react with any of them. These results suggest that recombinant N, S, and U274 proteins may be used as antigens for the development of serological assays for SARS-CoV.

ABSTRACTWe have used X-ray crystallography to determine the structure of a decay accelerating factor (DAF)-binding, clinic-derived isolate of echovirus 11 (EV11-207). The structures of the capsid proteins closely resemble those of capsid proteins of other picornaviruses. The structure allows us to interpret a series of amino acid changes produced by passaging EV11-207 in different cell lines as highlighting the locations of multiple receptor-binding sites on the virion surface. We suggest that a DAF-binding site is located at the fivefold axes of the virion, while the binding site for a distinct but as yet unidentified receptor is located within the canyon surrounding the virion fivefold axes.

The 5′ leader is documented to be an important regulatory element in many (+) ssRNA virus genome. To understand the significance of the 5′ leader RNA of PRRSV, we determined the complete leader sequences of fifteen different North American strains of PRRSV and predicted their secondary structures. Viruses analysed included three reference strains and nine field strains originating from different geographic locations. To further examine the leader region, one of the field strains was adapted to grow in tissue culture, and three clones were isolated. We also predicted the secondary structures of two European strains based on their published sequences. The predicted RNA secondary structures of the leader sequences suggested the existence of three conserved domains formed by the 5′ region of the leader among the North American strains, two of which were conserved in the European strains. A variable structural domain was predicted from the 3′ region of the leader sequences of the North American strains, where all tissue culture-adapted isolates were characterized by a stem-loop while field isolates were characterized by an internal bulge within the stem-loop.

The VP7 and VP4 genes of a group A rotavirus (Lp14) isolated from a lamb with diarrhea in Qinhai province, China, in 1981 were reverse transcribed, amplified by PCR, cloned, and sequenced. The virus was found to possess a VP7 gene, classifying it as a G10 type, and a VP4 gene which showed only limited homology with any other known VP4 gene, suggesting its classification as a new P type and providing further evidence for the vast diversity of group A rotaviruses. Copyright 1993, 1999 Academic Press