[Objective]Preservation and waterproof treatment are two crucial parts in wood protection, which can not only extend the service time, but also expand the application range of wood products. [Method] This work combine...[Objective]Preservation and waterproof treatment are two crucial parts in wood protection, which can not only extend the service time, but also expand the application range of wood products. [Method] This work combined CA with paraffin wax emulsion to treat wood samples, and basic properties of the compound system, such as stability （storage stability and centrifugal stability）, particle size and pH val-ue, and water repel ency （water absorption, shrinkage and swel ing） of treated sam-ples were investigated. [Result and Conclusion] 1） the compound systems of CA and paraffin latex had a favorable miscibility and stability; 2） compared with untreated wood, CA-treated samples showed poor water repel ing properties, whereas samples treated with the compound systems indicated an obvious reduction in water absorp-tion, and the shrinkage and swel ing of them were improved as wel .展开更多
[Objective] The aim was to develop the compound system of paraffin emulsion and CA based on natural surfactants to improve the properties of anti- mould and anti-blue stain. [Method] The paraffin wax emulsion with dif...[Objective] The aim was to develop the compound system of paraffin emulsion and CA based on natural surfactants to improve the properties of anti- mould and anti-blue stain. [Method] The paraffin wax emulsion with different con- centrations of 0.5%, 1.0% and 2.0% was added into CA （0.3% and 0.5%） to obtain six groups of compound systems. The full-cell process was applied to treat the sapwood of Pinus spp. at size of 50 mm （L）×20 mm （R）×5 mm （T）. Anti-mould and anti-blue stain tests were conducted using Botryodiplodia theobromae Pat., Spergi/lus niger V. Tiegh and Trichoderma viride Pers.ex Fr. according to the GB/T18261-200. [Result] Both paraffin wax emulsion and CA-B could prevent wood against mould and blue stain. However, within a certain range, anti-mould and anti-blue stain ef- fects of wood samples treated by the compound systems reduced slightly as the concentration of paraffin wax emulsion increased. [Conclusion] The research provides references for advancing use of wood biomass resources in a more efficient and more environment-friendly way.展开更多
Based on the state-of-the-art studies of solar-soil source heat pump compound system, operation patterns of solar-soil compound system were analyzed, particularly the advantages of parallel operation pattern. It is fo...Based on the state-of-the-art studies of solar-soil source heat pump compound system, operation patterns of solar-soil compound system were analyzed, particularly the advantages of parallel operation pattern. It is found that parallel operation pattern is better for solar-soil compound system. Furthermore, the heat balance issue of solar-soil compound system was emphatically analyzed from four aspects, which were annual analysis of heating and cooling load, the heat exchange of ground heat exchanger, capacity determination of solar-assisted heat sottrce and heat balance calculation of solar-soil compound system. Moreover, annual rate of heat balance in a solar-soil source heat pump compound system was calculated with a case study. It is shown that the annual heat unbalance ratio is 19%, which is less than 20%. As a result, the practical solar-soil compound system can basically maintain the heat balance of soil.展开更多
Based on the eco-economy theory,this paper analyzed the characteristics of the components of eco-economic compound system of karst region in Guizhou Province.The functional characteristics of eco-economic compound sys...Based on the eco-economy theory,this paper analyzed the characteristics of the components of eco-economic compound system of karst region in Guizhou Province.The functional characteristics of eco-economic compound system of karst region in Guizhou Province were analyzed.The functional characteristics were as follows:low biological production of Guizhou Province;weak capacity of ecosystem;slow speed of storage and accumulation of material and serious environmental pollution;low production and efficiency of energy;serious wastes of energy.On the basis of functional characteristics of eco-economic compound System in Karst region.Some views in terms of maintenance and reconstruction of compound system,were put forward,including laying stress on improving ecological system;choosing and cultivating the advanced species that suit the Karst region;improving the amount and speed of material accumulation,at the same time,introducing into advanced production technologies and management experience;reducing the energy efficiency of each section in economic system and improving the transformation efficiency of energy.展开更多
[Objective] An approach of stress relaxation was proposed in present work to investigate the interactions among the waterproof agent,preservative and wood.[Method] Paraffin emulsion waterproof using natural surfactant...[Objective] An approach of stress relaxation was proposed in present work to investigate the interactions among the waterproof agent,preservative and wood.[Method] Paraffin emulsion waterproof using natural surfactants was prepared at different concentrations of 0.5% and 2.0%,which were added into two concentrations（0.3%,0.5%） of copper azole（CA） to obtain compound systems,and one-time fullcell process was applied to treat the sapwood of Pinus spp.with a size of 10 mm（L） ×10 mm（R） ×10 mm（T）.[Result] Compressive stress relaxation behaviors at two moisture levels and room temperature were measured and the results were as follows：1） compared with control group,the stress relaxation of compound system treated groups reduced,whether at oven-dried state or air-dried state.2） Under oven-dried condition,CA could weaken the relaxation of treated samples and this effect became greater with increasing concentration of preservative,but an increase in the concentration of paraffin emulsion would slightly promote the relaxation of compound system treated samples.While under air-dried condition,both CA and paraffin wax emulsion lowered the relaxation which was inversely related to the concentrations of both agents.[Conclusion] The results were expected to shed new light on the various macroscopic properties of the compound system treated wood at a microscopic level,and to provide favorable scientific evidences and theoretical supports for the manufacture of waterproofing preservative-treated wood.展开更多
The rare earth Pr doped Ca1-xPrxMnO3 （x=0, 0.06, 0.08, 0.1, 0.12, and 0.14） compound bulk samples were prepared to study the effect of Pr doping on thermoelectric transport properties of CaMnO3 compound system. The ...The rare earth Pr doped Ca1-xPrxMnO3 （x=0, 0.06, 0.08, 0.1, 0.12, and 0.14） compound bulk samples were prepared to study the effect of Pr doping on thermoelectric transport properties of CaMnO3 compound system. The doped samples exhibited sin-gle phase composition within the experimental doping range, with condensed bulk microstructure and small porosities. The electrical resistivity was remarkably reduced for doped samples, on account of the enhanced carrier concentration;the absolute value of See-beck coefficient was deteriorated mainly due to enhanced electron carrier concentration. The electrical performances of the doped samples reflected by resistivity and Seebeck coefficient fluctuations were optimistically tuned, with an optimized power factor value of 0.342 mW/（m·K2） at 873 K for x=0.08 sample, which was very much higher comparing with that of the un-doped sample. The lattice thermal conduction was really confined, leading to distinctly repressed total thermal conductivity. The thermoelectric per-formance was noticeably improved by Pr doping and the dimensionless figure of merit ZT for the Ca0.92Pr0.08MnO3 compound was favorably optimized with the maximum value 0.16 at 873 K.展开更多
In high-intensity electromagnetic warfare,radar systems are persistently subjected to multi-jammer attacks,including potentially novel unknown jamming types that may emerge exclusively under wartime conditions.These j...In high-intensity electromagnetic warfare,radar systems are persistently subjected to multi-jammer attacks,including potentially novel unknown jamming types that may emerge exclusively under wartime conditions.These jamming signals severely degrade radar detection performance.Precise recognition of these unknown and compound jamming signals is critical to enhancing the anti-jamming capabilities and overall reliability of radar systems.To address this challenge,this article proposes a novel open-set compound jamming cognition(OSCJC)method.The proposed method employs a detection-classification dual-network architecture,which not only overcomes the false alarm and misdetection issues of traditional closed-set recognition methods when dealing with unknown jamming but also effectively addresses the performance bottleneck of existing open-set recognition techniques focusing on single jamming scenarios in compound jamming environments.To achieve unknown jamming detection,we first employ a consistency labeling strategy to train the detection network using diverse known jamming samples.This strategy enables the network to acquire highly generalizable jamming features,thereby accurately localizing candidate regions for individual jamming components within compound jamming.Subsequently,we introduce contrastive learning to optimize the classification network,significantly enhancing both intra-class clustering and inter-class separability in the jamming feature space.This method not only improves the recognition accuracy of the classification network for known jamming types but also enhances its sensitivity to unknown jamming types.Simulations and experimental data are used to verify the effectiveness of the proposed OSCJC method.Compared with the state-of-the-art open-set recognition methods,the proposed method demonstrates superior recognition accuracy and enhanced environmental adaptability.展开更多
We examined the rheological and gel properties of Auricularia auricula pulp solution and konjac glucomannan solution at different concentrations(1.2,2.4,3.6,4.8,and 6.0 g/100 mL)as well as A.auricula pulp/konjac gluco...We examined the rheological and gel properties of Auricularia auricula pulp solution and konjac glucomannan solution at different concentrations(1.2,2.4,3.6,4.8,and 6.0 g/100 mL)as well as A.auricula pulp/konjac glucomannan compound system at different mass ratios(4.8:1.2,3.6:2.4,2.4:3.6,and 1.2:4.8)and discussed the interaction mechanism.The results showed that the apparent viscosity,dynamic viscoelasticity,energy storage modulus(G’),and loss modulus(G”)of the compound system increased with the increase of A.auricula pulp mass ratio.The thixotropic ring decreased with the increase of A.auricula pulp mass ratio,indicating that A.auricula pulp could improve the thixotropy of the compound system.The results of the texture analysis and water retention test showed that konjac glucomannan was the decisive factor for the strength and hardness of A.auricula pulp/konjac glucomannan compound gel,and A.auricula pulp could significantly improve the elasticity,viscosity,and water-holding capacity of the compound system.based on Fourier transform infrared(FTir)spectroscopy and cryo-scanning electron microscopy(cryo-SEM)analyses,we preliminarily concluded that an interaction occurred between A.auricula pulp and konjac glucomannan in the compound system,and a gel network structure was formed.展开更多
OBJECTIVE:To systematically assess the safety and effectiveness of Compound E’jiao Jiang(复方阿胶浆,CEJ)for treating leukopenia.METHODS:Four English and four Chinese databases were searched for randomized controlled ...OBJECTIVE:To systematically assess the safety and effectiveness of Compound E’jiao Jiang(复方阿胶浆,CEJ)for treating leukopenia.METHODS:Four English and four Chinese databases were searched for randomized controlled trials(RCTs)on CEJ for treating leukopenia up to July 1,2024.Two researchers independently screened the studies and extracted necessary data.Methodological quality and risk of bias were assessed using the Cochrane risk-of-bias tool.Articles eligible for Meta-analysis were analyzed using RevMan.RESULTS:A total of 28 RCTs involving 2041 participants were included,with 1034 in the experimental group and 1007 in the control group.The Meta-analysis showed a significant effect of CEJ in treating leukopenia caused by tumor and immune diseases(three RCTs)[risk ratio(RR)=1.17,95%confidence interval(CI)(1.08,1.27),P=0.0002,I^(2)=35%].The combination of CEJ and Western Medicine showed superior results in terms of white blood cell(WBC)counts(fifteen RCTs)[mean difference(MD)=1.12,95%CI(0.83,1.42),P<0.00001,I^(2)=88%],Karnofsky Performance Status(KPS)levels(seven RCTs)[RR=1.39,95%CI(1.25,1.55),P<0.00001,I^(2)=36%],and mitigation of bone marrow toxicity(eleven RCTs)[RR=0.61,95%CI(0.54,0.69),P<0.00001,I^(2)=24%]compared to Western Medicine alone.Adverse events mainly included gastrointestinal and digestive reactions associated with chemotherapy drugs.CONCLUSION:CEJ alone or in combination with Western Medicine for treating leukopenia caused by tumor and immune diseases improved WBC counts,clinical efficacy,and quality of life.It also reduced bone marrow toxicity-induced leukopenia,enhanced the efficacy of chemotherapy while reducing its toxicity,and alleviated symptoms.No significant adverse events were reported in the RCTs,indicating favorable efficacy and safety.The Grading of Recommendations Assessment,Development and Evaluation assessment indicated a low level of evidence for CEJ in improving leukocyte elevation efficacy,KPS levels,and myelosuppressive toxicity.Therefore,large-scale,high-quality,rigorous multicenter double-blind controlled trials are recommended to strengthen the evidence level.展开更多
To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nido...To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nidocarboranes and alkynes directly afford two distinct types of 2D-3D fused carboranyl polycyclic compounds:3a-3f,4a-4d.The structures of this series of compounds were characterized by nuclear magnetic resonance spectroscopy,single-crystal X-ray diffraction,and high-resolution mass spectrometry,and a plausible reaction mechanism was proposed.Crystal structures reveal that the multiple rings in such 2D-3D fused carboranyl polycyclic compounds exhibit a certain degree of coplanarity.Furthermore,these compounds exhibited properties distinct from those of conventional 2D polycyclic systems.CCDC:2481988,3c,2481990,3f,2481986,4d.展开更多
Layered transition-metal compounds(LTMCs)feature stacked architectures,strong magnetic anisotropy,and tunable magnetic order,making them promising material platforms for low-power spintronic technologies and for enabl...Layered transition-metal compounds(LTMCs)feature stacked architectures,strong magnetic anisotropy,and tunable magnetic order,making them promising material platforms for low-power spintronic technologies and for enabling topological functionalities in the post-Moore era.Here we review recent progress on two-dimensional(2D)magnetism in LTMCs,emphasizing material taxonomy,intrinsic magnetic properties,and external-field controls.This review first presents a classification of LTMCs by crystal structure and chemistry—binary halides,chalcogenides,and ternary families(e.g.,MPX_(3),M_(m)X_(n)Te_(k),MnBi_(2)Te_(4))—followed by a summary of their coupling mechanisms,ordering temperatures,and dimensional effects.It then analyzes the modulation of exchange interactions,magnetic anisotropy,and topological states by electric-field gating,strain engineering,and ion intercalation,with representative experimental demonstrations.Notable advances include room-temperature ferromagnetic metals and semiconductors,observation of the quantum anomalous Hall effect(QAHE)in MnBi2Te4,and synergistic control of magnetic-topological states under multiple external stimuli.Persistent challenges involve the limited availability of intrinsic 2D magnetic semiconductors with high Curie temperatures(Tc),incomplete understanding of the microscopic couplings at interfaces and under quantum confinement,and device-level stability.We conclude by outlining opportunities that lie in the integration of multiscale characterization,first-principles theory,and cross-scale fabrication to precisely co-engineer magnetism,topology,and electronic structure,thereby advancing LTMCs toward spintronic and topological-quantum applications.展开更多
BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probi...BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probiotics have shown good potential in regulating the endocrine system and improving the intestinal microecology,providing new ideas for the treatment of breast hyperplasia.OBJECTIVE:To explore the effects and mechanisms of traditional Chinese medicine compounds and fermented probiotic compounds on breast hyperplasia in mice,providing new theoretical and experimental bases for the clinical treatment and prevention of breast hyperplasia.METHODS:(1)Network pharmacology tools were used to predict the anti-breast-hyperplasia activity of Herba Gueldenstaedtiae(Euphorbia humifusa),as well as its potential targets and signaling pathways.The databases included:TCMSP,OMIM,GeneCards database,UniProt website,Venny2.1.0 website,Metascape,HERB website,and STRING database,all of which are open-access databases.Network pharmacology can predict and screen key information such as the targets corresponding to the active ingredients of traditional Chinese medicine,disease targets,and action pathways through network analysis and computer-system analysis.Therefore,it has been increasingly widely used in the research of traditional Chinese medicine.(2)A breast hyperplasia model was induced in mice by injecting estrogen and progesterone.Mice in the normal blank group were injected intraperitoneally with normal saline every day.Mice in the model group and drugadministration groups were injected intraperitoneally with estradiol benzoate injection at a concentration of 0.5 mg/kg every day for 25 days.From the 26th day,the injection of estradiol benzoate injection was stopped.Mice in the normal blank group were injected intramuscularly with normal saline every day,and mice in the model group and drug-administration groups were injected intramuscularly with progesterone injection at a concentration of 5 mg/kg for 5 days.After the model was established,each group was given drugs respectively.The normal blank group and the model group were gavaged with 0.2 mL/d of normal saline;the positive blank group(Xiaozheng Pill group)was gavaged with an aqueous solution of Xiaozheng Pill at 0.9 mg/g;the low-,medium-and high-dose groups of Compound Herba Gueldenstaedtiae were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively;the low-,medium-and high-dose groups of traditional Chinese medicine-bacteria fermentation were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively.The administration was continuous for 30 days.RESULTS AND CONCLUSION:(1)The results of network pharmacology research showed that the Compound Herba Gueldenstaedtiae(Euphorbia humifusa)contained 46 active ingredients,which were related to 1213 potential targets.After comparison with 588 known breast-hyperplasia targets,it was speculated that 50 of these targets might be related to the direct effect of the compound on breast hyperplasia.(2)After drug intervention,there was no significant change in the high-dose group of Compound Herba Gueldenstaedtiae compared with the normal blank group.The liver indicators of the other intervention groups all significantly decreased(P<0.05).(3)In terms of kidney and uterine indicators,the medium-dose group of Compound Herba Gueldenstaedtiae decreased significantly compared with the normal blank group(P<0.05).In terms of the uterine index,the model group increased significantly compared with the normal blank group(P<0.01).(4)After 1-month drug treatment,the number of lobules and acini in the breast tissue of the Xiaozheng Pill group,the low,medium,and high-dose group of Compound Herba Gueldenstaedtiae,the low,medium,and highdose groups of traditional Chinese medicine-bacteria fermentation decreased,and the duct openings narrowed.With the increase of drug dose,diffuse hyperplasia of breast tissue was significantly improved.(5)The ELISA results showed that compared with the model group,the estrogen level was lower in the medium-dose group of traditional Chinese medicine-bacteria fermentation after the intervention(P<0.05).In addition,the follicle-stimulating hormone level in the low-dose group of Compound Herba Gueldenstaedtiae was lower than that of the model group(P<0.05).(6)The intervention in the mouse model led to changes in the abundance of short chain fatty acids and intestinal flora in all groups.To conclude,the Compound Herba Gueldenstaedtiae and its probiotic fermentation products significantly improved mammary gland hyperplasia in mice by regulating hormone levels,improving the structure of the gut microbiota,and increasing the content of shortchain fatty acids,providing new ideas and potential sources of drugs for the treatment of breast hyperplasia.展开更多
Light element compounds under high pressure display intriguing properties and applications,owing to their diverse bonding patterns and crystalline structures.However,the system of ternary Be-C-O compounds under high p...Light element compounds under high pressure display intriguing properties and applications,owing to their diverse bonding patterns and crystalline structures.However,the system of ternary Be-C-O compounds under high pressure,as the lightest representative of the IIA-IVA-VIA family,remains largely unexplored.Using a machine-learning-accelerated crystal structure search and first-principles calculations,Be-C-O phase diagrams are investigated at pressures ranging from 0 to 100 GPa.Four ternary compounds are proposed to be stable at corresponding pressures:BeCO_(3),Be_(2)CO_(4),Be_(2)C_(4)O_(3),and BeC_(4)O_(2).Analyses of electronic structure and chemical bonding further reveal how the structural diversity of these compounds is induced.Remarkably,Be_(2)C_(4)O_(3) and BeC_(4)O_(2) are recoverable to ambient conditions and possess both high energy density and high hardness.The volumetric energy densities of Be_(2)C_(4)O_(3) and BeC_(4)O_(2) could approach 9.03 and 7.94 kJ/cm^(3),respectively.The Vickers hardnesses of Be_(2)C_(4)O_(3) and BeC_(4)O_(2) are found to be close to 39.58 and 51.57 GPa,respectively.These findings demonstrate the structural and functional diversity of Be-C-O compounds under high pressure,providing guidance for further exploration of the IIA-IVA-VIA compounds.展开更多
To elucidate the variations in volatile organic compounds(VOCs)among widely cultivated japonica rice varieties in China and offer novel perspectives on flavor formation during rice-based beer brewing,nine prevalent Ch...To elucidate the variations in volatile organic compounds(VOCs)among widely cultivated japonica rice varieties in China and offer novel perspectives on flavor formation during rice-based beer brewing,nine prevalent Chinese japonica rice variaties were selected as experimental materials.Comprehensive analyses were conducted to investigate three key aspects:differences in VOCs among the selected japonica rice varieties,the retention of rice VOCs after beer brewing,and the influence of rice additives on beer sensory characteristics.Results showed that the total contents of VOCs in Wuyoudao 4(WYD4)and Nangeng 9108(NG9108)were significantly higher than those in the other varieties(P<0.05).The popcorn-flavor compound 2-acetyl-1-pyrroline(2-AP)was detected in Suigeng 27(SG27,26.80 ng/g),WYD4(25.25 ng/g),NG9108(21.18 ng/g),and Suigeng 18(SG18,11.62 ng/g),with the levels in the first three varieties significantly higher than those in SG18.Circular heatmap analysis classified the nine japonica varieties into three major categories:fragrant japonica from North China(WYD4),fragrant japonica from South China(NG9108),and others.Ten characteristic VOCs across the japonica varieties were identified by headspace solid-phase microextraction gas chromatography-mass spectrometry(HS-SPME-GC-MS).Using beer brewed with whole wheat as the control,we analyzed the VOCs and sensory characteristics of beer brewed with fragrant japonica rice as an additive.We found that rice VOCs were not detected in beer brewed with fragrant japonica rice as an additive.Adding rice promoted the formation of banana-like flavors and reduced the beer’s richness and mellowness.展开更多
Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable ...Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable strategy for constructing new carbon-oxygen bonds.In comparison with traditional thermal or metal-mediated carbene transfer reactions,visible-light-promoted multi-component reaction strategy provides a mild and eco-friendly approach to access densely functionalized molecules.Recently,visible-light-induced multi-component carbene transfer reactions of diazo compounds have been rapidly developed and attracted a great deal of research interest of chemists owing to their advantages of simple operation,mild condition,high atom economy and rich structural diversity.This paper summarizes the recent research progress on the visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers with various nucleophiles.The reaction patterns of different nucleophiles and their corresponding mechanism are described in this review.The future research direction and challenges in this area are also discussed.展开更多
AIM:To investigate the genetic basis of Weill-Marchesani syndrome(WMS)in a Chinese family and clarify the pathogenic mechanism of novel ADAMTS17 mutations.METHODS:Comprehensive clinical assessments and genetic analyse...AIM:To investigate the genetic basis of Weill-Marchesani syndrome(WMS)in a Chinese family and clarify the pathogenic mechanism of novel ADAMTS17 mutations.METHODS:Comprehensive clinical assessments and genetic analyses were performed on a Chinese family with two affected siblings.Whole-exome sequencing(WES)was conducted for the proband and other family members.Bioinformatics tools were used to evaluate the conservation,predicted pathogenicity,and structural effects of the identified ADAMTS17 variants.In addition,protein structure modeling was applied to assess the functional impacts of the mutations.RESULTS:The proband(a 32-year-old male)and his elder sister(42y)presented typical clinical features of WMS,including short stature,brachydactyly,high myopia,ectopia lentis,and secondary glaucoma.WES identified a novel compound heterozygous mutation in ADAMTS17:a splicing mutation(c.451-2A>G)inherited from the father and a missense mutation(c.1043G>A;p.C348Y)inherited from the mother.The splicing mutation disrupted normal mRNA splicing and processing,leading to premature translation termination.The missense mutation,which is located in the metalloprotease catalytic domain,was predicted to abolish a critical disulfide bond,thereby impairing protein stability.Both mutations exhibited high evolutionary conservation and were predicted to be pathogenic by multiple bioinformatics algorithms.CONCLUSION:A novel compound heterozygous mutation in ADAMTS17 is identified in this WMS-affected Chinese family,and its pathogenicity is verified via bioinformatics analysis and protein structural modeling.These findings are expected to facilitate the genetic diagnosis of WMS and deepen the understanding of its molecular pathogenesis.展开更多
Temperature has a substantial impact on the emission of biogenic volatile organic compounds(BVOCs).Moder-ate warm temperatures,e.g.,30–40°C,could boost plant metabolism,increasing BVOC emissions.Against the back...Temperature has a substantial impact on the emission of biogenic volatile organic compounds(BVOCs).Moder-ate warm temperatures,e.g.,30–40°C,could boost plant metabolism,increasing BVOC emissions.Against the backdrop of global warming,plants emit more BVOCs to cope with thermal stress,leading to elevated concen-trations of tropospheric ozone(O_(3))and secondary organic aerosols(SOA).In recent years,a considerable body of research has explored the interaction between tree species and BVOCs under the influence of various environ-mental factors.Although many studies have examined explored the temperature dependence of BVOC emissions in the past,few studies have conducted a comprehensive and in-depth investigation into the impacts of tempera-ture.This review summarizes the relevant studies on BVOCs in the past decade,including the main biosynthetic pathways,emission observation techniques and emission inventories,as well as how temperature affects isoprene and monoterpene emission rates and the formation of O_(3) and SOA.Our work offers a theoretical foundation and guidance for future efforts to advance the comprehension of BVOC emission characteristics and develop strategies to mitigate secondary pollution.展开更多
A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 pol...A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 polycyclic aromatic hydrocarbons(PAHs),70 polychlorinated biphenyls(PCBs),123 pesticides,20 phthalate esters(PAEs),4 organophosphate esters(OPEs),9 synthetic musks(SMs),and 5 UV filters(UVs)in water.No-tably,this method provided a decent linearity of calibration standards(R^(2)>0.999),excellent method limits of quantification(MLOQs)(0.12–11.41 ng/L),satisfactory matrix spiking recovery rates(60.4%–126%),and high precision(intra-day relative standard deviations(RSDs):1.0%–10.0%,inter-day RSDs:3.0%–15.0%,and inter-week RSDs:3.4%–15.7%),making it suitable for trace-level studies.Statistical analysis revealed that SVOCs with higher volatility exhibited enhanced recovery rates.Validation of the methodology involved analyzing SVOCs in real spring water and river water samples.Twenty-seven SVOCs were detected in spring water and 58 in river water,with an average concentration of 631.73 and 16,095 ng/L,respectively.Among the detected SVOCs,PAEs constituted the predominant proportion.This study underscored the presence of SVOCs contamination specifi-cally within the spring water,although SVOCs concentrations in river water were significantly greater than those found in spring water.In summary,this sensitive method based on SPE–GC–MS/MS was successfully developed and validated for the rapid analysis of a diverse array of 256 SVOCs at trace levels in water,including not only the traditional highly valued PAHs,PCBs,pesticides,and PAEs,but also the emerging OPEs,UVs,and SMs.展开更多
Endogenous hydrogen systems,consisting of metal–organic coordination catalysts and alcohols,have been widely applied for the transfer hydrogenation(TH)of biomass-derived carbonyl compounds in recent years.Metal-organ...Endogenous hydrogen systems,consisting of metal–organic coordination catalysts and alcohols,have been widely applied for the transfer hydrogenation(TH)of biomass-derived carbonyl compounds in recent years.Metal-organic coordination catalysts showed satisfactory ability of TH in the secondary alcohols,but most of them could not effectively employ the cheaper primary alcohols as hydrogen donors.Furthermore,they commonly contained high metal contents,which also led to low catalytic efficiency in significant measure.In this work,we constructed a novel magnesium single-atom catalyst(Mg-NC)with merely 0.37 wt%Mg by means of a combined self-assembly and pyrolysis strategy.The characterization results indicated that Mg was atomically dispersed and it was coordinated with four pyridinic-N in Mg-NC.Due to the obvious electron transfer from Mg to its coordinated pyridinic-N,Mg–N_(4)active centers displayed high Lewis acid-base strength with abundant content,which brought remarkable catalytic activity.When Mg-NC was used for the TH of 5-hydroxymethylfurfural(HMF)in ethanol(EtOH),2,5-bis(hydroxymethyl)furan(BHMF)yield was up to 96.3%with high productivity of 19.85 molBHMF mol_(Mg)^(−1)h^(−1)at 150°C for 5 h.More interestingly,the process of TH over Mg-NC in EtOH was proved to proceed via the hydrogen radical mechanism.Additionally,Mg-NC exhibited powerful catalytic universality;it could not only utilize other primary alcohols(such as n-propanol and n-butanol)as hydrogen donors,but also catalyze the TH of other carbonyl compounds(such as furfural,5-methylfurfural,benzaldehyde,cyclohexanone,and levulinic acid).Overall,this work offered some important clues and references to reinforce the hydrogen-supplying ability of primary alcohols in the TH of various biomass-derived carbonyl compounds to high-value fine chemicals.展开更多
Chili fermentation is one of the most important processes in the production of Pixian Douban(PXDB),which determines the flavor and product quality of PXDB.However,the maturity of fermented chili mainly depends on empi...Chili fermentation is one of the most important processes in the production of Pixian Douban(PXDB),which determines the flavor and product quality of PXDB.However,the maturity of fermented chili mainly depends on empirical judgment,which can not satisfy the need for standardized production of PXDB.Therefore,this study aimed to investigate volatile and non-volatile substances during the maturation process and to find markers related to the maturity of fermented chili.Two-dimensional gas chromatography-mass spectrometry(GC×GC-MS)combined with multivariate statistical analysis and relative odor activity values(ROAV)analysis revealed that 2-methoxy-3-isobutyl pyrazine,linalool,3-(methylthio)propionaldehyde,myrcene,and decanal(ROAV≥1,VIP>1,P<0.05)were regarded as potentially active aromatic markers for differentiating fermentation time.Additionally,ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLCQTOF-MS)combined with multivariate statistical analysis revealed that 25 compounds could serve as differentiated non-volatile compounds.The correlation of maturity-related physicochemical indicators with volatile and nonvolatile compounds revealed that four volatile compounds(2-methoxy-3-isobutylpyrazine,linalool,myrcene,and decanal)along with seven non-volatile compounds could serve as markers for evaluating the maturity of fermented chili.This study is expected to establish a standard for the determination of the maturity the fermented chili and lay the foundation for intelligent production of PXDB.展开更多
基金Supported by Beijing Municipal Student Research Training Program in Beijing ForestryUniversity(S201310022020)Fundamental Research Funds for the Central Universities(TD2011-14)~~
文摘[Objective]Preservation and waterproof treatment are two crucial parts in wood protection, which can not only extend the service time, but also expand the application range of wood products. [Method] This work combined CA with paraffin wax emulsion to treat wood samples, and basic properties of the compound system, such as stability （storage stability and centrifugal stability）, particle size and pH val-ue, and water repel ency （water absorption, shrinkage and swel ing） of treated sam-ples were investigated. [Result and Conclusion] 1） the compound systems of CA and paraffin latex had a favorable miscibility and stability; 2） compared with untreated wood, CA-treated samples showed poor water repel ing properties, whereas samples treated with the compound systems indicated an obvious reduction in water absorp-tion, and the shrinkage and swel ing of them were improved as wel .
基金Supported by Beijing Municipal Student Research Training Program in Beijing Forestry University(S201410022055)Fundamental Research Funds for the Central Universities in China(No.TD2011-14)~~
文摘[Objective] The aim was to develop the compound system of paraffin emulsion and CA based on natural surfactants to improve the properties of anti- mould and anti-blue stain. [Method] The paraffin wax emulsion with different con- centrations of 0.5%, 1.0% and 2.0% was added into CA （0.3% and 0.5%） to obtain six groups of compound systems. The full-cell process was applied to treat the sapwood of Pinus spp. at size of 50 mm （L）×20 mm （R）×5 mm （T）. Anti-mould and anti-blue stain tests were conducted using Botryodiplodia theobromae Pat., Spergi/lus niger V. Tiegh and Trichoderma viride Pers.ex Fr. according to the GB/T18261-200. [Result] Both paraffin wax emulsion and CA-B could prevent wood against mould and blue stain. However, within a certain range, anti-mould and anti-blue stain ef- fects of wood samples treated by the compound systems reduced slightly as the concentration of paraffin wax emulsion increased. [Conclusion] The research provides references for advancing use of wood biomass resources in a more efficient and more environment-friendly way.
基金Project(50838009) supported by the National Natural Science Foundation of ChinaProject(2010DFA72740-05) supported by the International Science & Technology Cooperation Program of China
文摘Based on the state-of-the-art studies of solar-soil source heat pump compound system, operation patterns of solar-soil compound system were analyzed, particularly the advantages of parallel operation pattern. It is found that parallel operation pattern is better for solar-soil compound system. Furthermore, the heat balance issue of solar-soil compound system was emphatically analyzed from four aspects, which were annual analysis of heating and cooling load, the heat exchange of ground heat exchanger, capacity determination of solar-assisted heat sottrce and heat balance calculation of solar-soil compound system. Moreover, annual rate of heat balance in a solar-soil source heat pump compound system was calculated with a case study. It is shown that the annual heat unbalance ratio is 19%, which is less than 20%. As a result, the practical solar-soil compound system can basically maintain the heat balance of soil.
文摘Based on the eco-economy theory,this paper analyzed the characteristics of the components of eco-economic compound system of karst region in Guizhou Province.The functional characteristics of eco-economic compound system of karst region in Guizhou Province were analyzed.The functional characteristics were as follows:low biological production of Guizhou Province;weak capacity of ecosystem;slow speed of storage and accumulation of material and serious environmental pollution;low production and efficiency of energy;serious wastes of energy.On the basis of functional characteristics of eco-economic compound System in Karst region.Some views in terms of maintenance and reconstruction of compound system,were put forward,including laying stress on improving ecological system;choosing and cultivating the advanced species that suit the Karst region;improving the amount and speed of material accumulation,at the same time,introducing into advanced production technologies and management experience;reducing the energy efficiency of each section in economic system and improving the transformation efficiency of energy.
文摘[Objective] An approach of stress relaxation was proposed in present work to investigate the interactions among the waterproof agent,preservative and wood.[Method] Paraffin emulsion waterproof using natural surfactants was prepared at different concentrations of 0.5% and 2.0%,which were added into two concentrations（0.3%,0.5%） of copper azole（CA） to obtain compound systems,and one-time fullcell process was applied to treat the sapwood of Pinus spp.with a size of 10 mm（L） ×10 mm（R） ×10 mm（T）.[Result] Compressive stress relaxation behaviors at two moisture levels and room temperature were measured and the results were as follows：1） compared with control group,the stress relaxation of compound system treated groups reduced,whether at oven-dried state or air-dried state.2） Under oven-dried condition,CA could weaken the relaxation of treated samples and this effect became greater with increasing concentration of preservative,but an increase in the concentration of paraffin emulsion would slightly promote the relaxation of compound system treated samples.While under air-dried condition,both CA and paraffin wax emulsion lowered the relaxation which was inversely related to the concentrations of both agents.[Conclusion] The results were expected to shed new light on the various macroscopic properties of the compound system treated wood at a microscopic level,and to provide favorable scientific evidences and theoretical supports for the manufacture of waterproofing preservative-treated wood.
基金Project supported by National Natural Science Foundation of China(50801002)Beijing Municipal Natural Science Foundation(2112007)Basic and Advanced Technology Research Project of Henan Province(132300410071)
文摘The rare earth Pr doped Ca1-xPrxMnO3 （x=0, 0.06, 0.08, 0.1, 0.12, and 0.14） compound bulk samples were prepared to study the effect of Pr doping on thermoelectric transport properties of CaMnO3 compound system. The doped samples exhibited sin-gle phase composition within the experimental doping range, with condensed bulk microstructure and small porosities. The electrical resistivity was remarkably reduced for doped samples, on account of the enhanced carrier concentration;the absolute value of See-beck coefficient was deteriorated mainly due to enhanced electron carrier concentration. The electrical performances of the doped samples reflected by resistivity and Seebeck coefficient fluctuations were optimistically tuned, with an optimized power factor value of 0.342 mW/（m·K2） at 873 K for x=0.08 sample, which was very much higher comparing with that of the un-doped sample. The lattice thermal conduction was really confined, leading to distinctly repressed total thermal conductivity. The thermoelectric per-formance was noticeably improved by Pr doping and the dimensionless figure of merit ZT for the Ca0.92Pr0.08MnO3 compound was favorably optimized with the maximum value 0.16 at 873 K.
文摘In high-intensity electromagnetic warfare,radar systems are persistently subjected to multi-jammer attacks,including potentially novel unknown jamming types that may emerge exclusively under wartime conditions.These jamming signals severely degrade radar detection performance.Precise recognition of these unknown and compound jamming signals is critical to enhancing the anti-jamming capabilities and overall reliability of radar systems.To address this challenge,this article proposes a novel open-set compound jamming cognition(OSCJC)method.The proposed method employs a detection-classification dual-network architecture,which not only overcomes the false alarm and misdetection issues of traditional closed-set recognition methods when dealing with unknown jamming but also effectively addresses the performance bottleneck of existing open-set recognition techniques focusing on single jamming scenarios in compound jamming environments.To achieve unknown jamming detection,we first employ a consistency labeling strategy to train the detection network using diverse known jamming samples.This strategy enables the network to acquire highly generalizable jamming features,thereby accurately localizing candidate regions for individual jamming components within compound jamming.Subsequently,we introduce contrastive learning to optimize the classification network,significantly enhancing both intra-class clustering and inter-class separability in the jamming feature space.This method not only improves the recognition accuracy of the classification network for known jamming types but also enhances its sensitivity to unknown jamming types.Simulations and experimental data are used to verify the effectiveness of the proposed OSCJC method.Compared with the state-of-the-art open-set recognition methods,the proposed method demonstrates superior recognition accuracy and enhanced environmental adaptability.
基金supported by the Jilin Province Science and Technology Department Key research and Development Project“Low sugar rice products base material development and application research”(20210202058NC).
文摘We examined the rheological and gel properties of Auricularia auricula pulp solution and konjac glucomannan solution at different concentrations(1.2,2.4,3.6,4.8,and 6.0 g/100 mL)as well as A.auricula pulp/konjac glucomannan compound system at different mass ratios(4.8:1.2,3.6:2.4,2.4:3.6,and 1.2:4.8)and discussed the interaction mechanism.The results showed that the apparent viscosity,dynamic viscoelasticity,energy storage modulus(G’),and loss modulus(G”)of the compound system increased with the increase of A.auricula pulp mass ratio.The thixotropic ring decreased with the increase of A.auricula pulp mass ratio,indicating that A.auricula pulp could improve the thixotropy of the compound system.The results of the texture analysis and water retention test showed that konjac glucomannan was the decisive factor for the strength and hardness of A.auricula pulp/konjac glucomannan compound gel,and A.auricula pulp could significantly improve the elasticity,viscosity,and water-holding capacity of the compound system.based on Fourier transform infrared(FTir)spectroscopy and cryo-scanning electron microscopy(cryo-SEM)analyses,we preliminarily concluded that an interaction occurred between A.auricula pulp and konjac glucomannan in the compound system,and a gel network structure was formed.
基金Supported by The Qihuang Scholars Support Program of the National Administration of Traditional Chinese Medicinet:2021 Qihuang Scholars Support Project(National Chinese Medicine Teaching Letter[2022]6)National Traditional Medicine Administration's Project for Establishing National Famous and Elderly Traditional Medicine Transmission Workshops:Xie Yanming National Famous Traditional Chinese Medicine Expert Transmission Studio(National Chinese Medicine Education Letter[2022]75)。
文摘OBJECTIVE:To systematically assess the safety and effectiveness of Compound E’jiao Jiang(复方阿胶浆,CEJ)for treating leukopenia.METHODS:Four English and four Chinese databases were searched for randomized controlled trials(RCTs)on CEJ for treating leukopenia up to July 1,2024.Two researchers independently screened the studies and extracted necessary data.Methodological quality and risk of bias were assessed using the Cochrane risk-of-bias tool.Articles eligible for Meta-analysis were analyzed using RevMan.RESULTS:A total of 28 RCTs involving 2041 participants were included,with 1034 in the experimental group and 1007 in the control group.The Meta-analysis showed a significant effect of CEJ in treating leukopenia caused by tumor and immune diseases(three RCTs)[risk ratio(RR)=1.17,95%confidence interval(CI)(1.08,1.27),P=0.0002,I^(2)=35%].The combination of CEJ and Western Medicine showed superior results in terms of white blood cell(WBC)counts(fifteen RCTs)[mean difference(MD)=1.12,95%CI(0.83,1.42),P<0.00001,I^(2)=88%],Karnofsky Performance Status(KPS)levels(seven RCTs)[RR=1.39,95%CI(1.25,1.55),P<0.00001,I^(2)=36%],and mitigation of bone marrow toxicity(eleven RCTs)[RR=0.61,95%CI(0.54,0.69),P<0.00001,I^(2)=24%]compared to Western Medicine alone.Adverse events mainly included gastrointestinal and digestive reactions associated with chemotherapy drugs.CONCLUSION:CEJ alone or in combination with Western Medicine for treating leukopenia caused by tumor and immune diseases improved WBC counts,clinical efficacy,and quality of life.It also reduced bone marrow toxicity-induced leukopenia,enhanced the efficacy of chemotherapy while reducing its toxicity,and alleviated symptoms.No significant adverse events were reported in the RCTs,indicating favorable efficacy and safety.The Grading of Recommendations Assessment,Development and Evaluation assessment indicated a low level of evidence for CEJ in improving leukocyte elevation efficacy,KPS levels,and myelosuppressive toxicity.Therefore,large-scale,high-quality,rigorous multicenter double-blind controlled trials are recommended to strengthen the evidence level.
文摘To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nidocarboranes and alkynes directly afford two distinct types of 2D-3D fused carboranyl polycyclic compounds:3a-3f,4a-4d.The structures of this series of compounds were characterized by nuclear magnetic resonance spectroscopy,single-crystal X-ray diffraction,and high-resolution mass spectrometry,and a plausible reaction mechanism was proposed.Crystal structures reveal that the multiple rings in such 2D-3D fused carboranyl polycyclic compounds exhibit a certain degree of coplanarity.Furthermore,these compounds exhibited properties distinct from those of conventional 2D polycyclic systems.CCDC:2481988,3c,2481990,3f,2481986,4d.
基金supported by the National KeyR&D Program of China(Grant No.2024YFB3817400)the National Natural Science Foundation of China(Grants No.12274276 and No.U24A6002)+1 种基金the Natural Science Foundation of Shanxi Province(China)(Grant No.202403021223008)Supported by Scientific and Technology Innovation Programs of Higher Education Institutions in Shanxi(Grant No.2024Q017 and No.2025L043).
文摘Layered transition-metal compounds(LTMCs)feature stacked architectures,strong magnetic anisotropy,and tunable magnetic order,making them promising material platforms for low-power spintronic technologies and for enabling topological functionalities in the post-Moore era.Here we review recent progress on two-dimensional(2D)magnetism in LTMCs,emphasizing material taxonomy,intrinsic magnetic properties,and external-field controls.This review first presents a classification of LTMCs by crystal structure and chemistry—binary halides,chalcogenides,and ternary families(e.g.,MPX_(3),M_(m)X_(n)Te_(k),MnBi_(2)Te_(4))—followed by a summary of their coupling mechanisms,ordering temperatures,and dimensional effects.It then analyzes the modulation of exchange interactions,magnetic anisotropy,and topological states by electric-field gating,strain engineering,and ion intercalation,with representative experimental demonstrations.Notable advances include room-temperature ferromagnetic metals and semiconductors,observation of the quantum anomalous Hall effect(QAHE)in MnBi2Te4,and synergistic control of magnetic-topological states under multiple external stimuli.Persistent challenges involve the limited availability of intrinsic 2D magnetic semiconductors with high Curie temperatures(Tc),incomplete understanding of the microscopic couplings at interfaces and under quantum confinement,and device-level stability.We conclude by outlining opportunities that lie in the integration of multiscale characterization,first-principles theory,and cross-scale fabrication to precisely co-engineer magnetism,topology,and electronic structure,thereby advancing LTMCs toward spintronic and topological-quantum applications.
文摘BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probiotics have shown good potential in regulating the endocrine system and improving the intestinal microecology,providing new ideas for the treatment of breast hyperplasia.OBJECTIVE:To explore the effects and mechanisms of traditional Chinese medicine compounds and fermented probiotic compounds on breast hyperplasia in mice,providing new theoretical and experimental bases for the clinical treatment and prevention of breast hyperplasia.METHODS:(1)Network pharmacology tools were used to predict the anti-breast-hyperplasia activity of Herba Gueldenstaedtiae(Euphorbia humifusa),as well as its potential targets and signaling pathways.The databases included:TCMSP,OMIM,GeneCards database,UniProt website,Venny2.1.0 website,Metascape,HERB website,and STRING database,all of which are open-access databases.Network pharmacology can predict and screen key information such as the targets corresponding to the active ingredients of traditional Chinese medicine,disease targets,and action pathways through network analysis and computer-system analysis.Therefore,it has been increasingly widely used in the research of traditional Chinese medicine.(2)A breast hyperplasia model was induced in mice by injecting estrogen and progesterone.Mice in the normal blank group were injected intraperitoneally with normal saline every day.Mice in the model group and drugadministration groups were injected intraperitoneally with estradiol benzoate injection at a concentration of 0.5 mg/kg every day for 25 days.From the 26th day,the injection of estradiol benzoate injection was stopped.Mice in the normal blank group were injected intramuscularly with normal saline every day,and mice in the model group and drug-administration groups were injected intramuscularly with progesterone injection at a concentration of 5 mg/kg for 5 days.After the model was established,each group was given drugs respectively.The normal blank group and the model group were gavaged with 0.2 mL/d of normal saline;the positive blank group(Xiaozheng Pill group)was gavaged with an aqueous solution of Xiaozheng Pill at 0.9 mg/g;the low-,medium-and high-dose groups of Compound Herba Gueldenstaedtiae were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively;the low-,medium-and high-dose groups of traditional Chinese medicine-bacteria fermentation were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively.The administration was continuous for 30 days.RESULTS AND CONCLUSION:(1)The results of network pharmacology research showed that the Compound Herba Gueldenstaedtiae(Euphorbia humifusa)contained 46 active ingredients,which were related to 1213 potential targets.After comparison with 588 known breast-hyperplasia targets,it was speculated that 50 of these targets might be related to the direct effect of the compound on breast hyperplasia.(2)After drug intervention,there was no significant change in the high-dose group of Compound Herba Gueldenstaedtiae compared with the normal blank group.The liver indicators of the other intervention groups all significantly decreased(P<0.05).(3)In terms of kidney and uterine indicators,the medium-dose group of Compound Herba Gueldenstaedtiae decreased significantly compared with the normal blank group(P<0.05).In terms of the uterine index,the model group increased significantly compared with the normal blank group(P<0.01).(4)After 1-month drug treatment,the number of lobules and acini in the breast tissue of the Xiaozheng Pill group,the low,medium,and high-dose group of Compound Herba Gueldenstaedtiae,the low,medium,and highdose groups of traditional Chinese medicine-bacteria fermentation decreased,and the duct openings narrowed.With the increase of drug dose,diffuse hyperplasia of breast tissue was significantly improved.(5)The ELISA results showed that compared with the model group,the estrogen level was lower in the medium-dose group of traditional Chinese medicine-bacteria fermentation after the intervention(P<0.05).In addition,the follicle-stimulating hormone level in the low-dose group of Compound Herba Gueldenstaedtiae was lower than that of the model group(P<0.05).(6)The intervention in the mouse model led to changes in the abundance of short chain fatty acids and intestinal flora in all groups.To conclude,the Compound Herba Gueldenstaedtiae and its probiotic fermentation products significantly improved mammary gland hyperplasia in mice by regulating hormone levels,improving the structure of the gut microbiota,and increasing the content of shortchain fatty acids,providing new ideas and potential sources of drugs for the treatment of breast hyperplasia.
基金supported by the National Key R&D Program of China(Grant Nos.2018YFA0703404 and 2017YFA0403704)the National Natural Science Foundation of China(Grant Nos.11774121 and 91745203)the Program for Changjiang Scholars and Innovative Research Team in University(Grant No.IRT_15R23).
文摘Light element compounds under high pressure display intriguing properties and applications,owing to their diverse bonding patterns and crystalline structures.However,the system of ternary Be-C-O compounds under high pressure,as the lightest representative of the IIA-IVA-VIA family,remains largely unexplored.Using a machine-learning-accelerated crystal structure search and first-principles calculations,Be-C-O phase diagrams are investigated at pressures ranging from 0 to 100 GPa.Four ternary compounds are proposed to be stable at corresponding pressures:BeCO_(3),Be_(2)CO_(4),Be_(2)C_(4)O_(3),and BeC_(4)O_(2).Analyses of electronic structure and chemical bonding further reveal how the structural diversity of these compounds is induced.Remarkably,Be_(2)C_(4)O_(3) and BeC_(4)O_(2) are recoverable to ambient conditions and possess both high energy density and high hardness.The volumetric energy densities of Be_(2)C_(4)O_(3) and BeC_(4)O_(2) could approach 9.03 and 7.94 kJ/cm^(3),respectively.The Vickers hardnesses of Be_(2)C_(4)O_(3) and BeC_(4)O_(2) are found to be close to 39.58 and 51.57 GPa,respectively.These findings demonstrate the structural and functional diversity of Be-C-O compounds under high pressure,providing guidance for further exploration of the IIA-IVA-VIA compounds.
基金supported by the Natural Science Foundation of Zhejiang Province,China(Grant No.LTGN24C020004)the Enterprise Cooperation Project,China(Grant No.HRJYH-202330)+1 种基金the Zhejiang Province Pioneer and Bellwethers Research&Development Project of Science and Technology,China(Grant No.2023C02014)the Central Public-Interest Scientific Institution Basal Research Fund,China(Grant No.CPSIBRFCNRRI-202303).
文摘To elucidate the variations in volatile organic compounds(VOCs)among widely cultivated japonica rice varieties in China and offer novel perspectives on flavor formation during rice-based beer brewing,nine prevalent Chinese japonica rice variaties were selected as experimental materials.Comprehensive analyses were conducted to investigate three key aspects:differences in VOCs among the selected japonica rice varieties,the retention of rice VOCs after beer brewing,and the influence of rice additives on beer sensory characteristics.Results showed that the total contents of VOCs in Wuyoudao 4(WYD4)and Nangeng 9108(NG9108)were significantly higher than those in the other varieties(P<0.05).The popcorn-flavor compound 2-acetyl-1-pyrroline(2-AP)was detected in Suigeng 27(SG27,26.80 ng/g),WYD4(25.25 ng/g),NG9108(21.18 ng/g),and Suigeng 18(SG18,11.62 ng/g),with the levels in the first three varieties significantly higher than those in SG18.Circular heatmap analysis classified the nine japonica varieties into three major categories:fragrant japonica from North China(WYD4),fragrant japonica from South China(NG9108),and others.Ten characteristic VOCs across the japonica varieties were identified by headspace solid-phase microextraction gas chromatography-mass spectrometry(HS-SPME-GC-MS).Using beer brewed with whole wheat as the control,we analyzed the VOCs and sensory characteristics of beer brewed with fragrant japonica rice as an additive.We found that rice VOCs were not detected in beer brewed with fragrant japonica rice as an additive.Adding rice promoted the formation of banana-like flavors and reduced the beer’s richness and mellowness.
基金Science and Technology Foundation of Guizhou Province(No.QKHJC-ZK[2024]654)Guizhou Provincial University Key Laboratory of Advanced Functional Electronic Materials(No.QJJ[2023]021).
文摘Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable strategy for constructing new carbon-oxygen bonds.In comparison with traditional thermal or metal-mediated carbene transfer reactions,visible-light-promoted multi-component reaction strategy provides a mild and eco-friendly approach to access densely functionalized molecules.Recently,visible-light-induced multi-component carbene transfer reactions of diazo compounds have been rapidly developed and attracted a great deal of research interest of chemists owing to their advantages of simple operation,mild condition,high atom economy and rich structural diversity.This paper summarizes the recent research progress on the visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers with various nucleophiles.The reaction patterns of different nucleophiles and their corresponding mechanism are described in this review.The future research direction and challenges in this area are also discussed.
文摘AIM:To investigate the genetic basis of Weill-Marchesani syndrome(WMS)in a Chinese family and clarify the pathogenic mechanism of novel ADAMTS17 mutations.METHODS:Comprehensive clinical assessments and genetic analyses were performed on a Chinese family with two affected siblings.Whole-exome sequencing(WES)was conducted for the proband and other family members.Bioinformatics tools were used to evaluate the conservation,predicted pathogenicity,and structural effects of the identified ADAMTS17 variants.In addition,protein structure modeling was applied to assess the functional impacts of the mutations.RESULTS:The proband(a 32-year-old male)and his elder sister(42y)presented typical clinical features of WMS,including short stature,brachydactyly,high myopia,ectopia lentis,and secondary glaucoma.WES identified a novel compound heterozygous mutation in ADAMTS17:a splicing mutation(c.451-2A>G)inherited from the father and a missense mutation(c.1043G>A;p.C348Y)inherited from the mother.The splicing mutation disrupted normal mRNA splicing and processing,leading to premature translation termination.The missense mutation,which is located in the metalloprotease catalytic domain,was predicted to abolish a critical disulfide bond,thereby impairing protein stability.Both mutations exhibited high evolutionary conservation and were predicted to be pathogenic by multiple bioinformatics algorithms.CONCLUSION:A novel compound heterozygous mutation in ADAMTS17 is identified in this WMS-affected Chinese family,and its pathogenicity is verified via bioinformatics analysis and protein structural modeling.These findings are expected to facilitate the genetic diagnosis of WMS and deepen the understanding of its molecular pathogenesis.
基金supported by the National Key R&D Program of China(No.2024YFC3714200)Guangxi Key Research and Development Program,China(No.Guike AB24010074)+2 种基金the National Natural Science Foundation of China(Nos.22276099,U24A20515 and 22361162668)the Natural Science Foundation of Jiangsu Province(No.BK20240036)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX24_1529).
文摘Temperature has a substantial impact on the emission of biogenic volatile organic compounds(BVOCs).Moder-ate warm temperatures,e.g.,30–40°C,could boost plant metabolism,increasing BVOC emissions.Against the backdrop of global warming,plants emit more BVOCs to cope with thermal stress,leading to elevated concen-trations of tropospheric ozone(O_(3))and secondary organic aerosols(SOA).In recent years,a considerable body of research has explored the interaction between tree species and BVOCs under the influence of various environ-mental factors.Although many studies have examined explored the temperature dependence of BVOC emissions in the past,few studies have conducted a comprehensive and in-depth investigation into the impacts of tempera-ture.This review summarizes the relevant studies on BVOCs in the past decade,including the main biosynthetic pathways,emission observation techniques and emission inventories,as well as how temperature affects isoprene and monoterpene emission rates and the formation of O_(3) and SOA.Our work offers a theoretical foundation and guidance for future efforts to advance the comprehension of BVOC emission characteristics and develop strategies to mitigate secondary pollution.
基金supported by the National Natural Science Foundation of China(No.51939009)Shenzhen Science and Technology Program(Nos.JCYJ20241202125905008 and GXWD20201231165807007-20200810165349001).
文摘A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 polycyclic aromatic hydrocarbons(PAHs),70 polychlorinated biphenyls(PCBs),123 pesticides,20 phthalate esters(PAEs),4 organophosphate esters(OPEs),9 synthetic musks(SMs),and 5 UV filters(UVs)in water.No-tably,this method provided a decent linearity of calibration standards(R^(2)>0.999),excellent method limits of quantification(MLOQs)(0.12–11.41 ng/L),satisfactory matrix spiking recovery rates(60.4%–126%),and high precision(intra-day relative standard deviations(RSDs):1.0%–10.0%,inter-day RSDs:3.0%–15.0%,and inter-week RSDs:3.4%–15.7%),making it suitable for trace-level studies.Statistical analysis revealed that SVOCs with higher volatility exhibited enhanced recovery rates.Validation of the methodology involved analyzing SVOCs in real spring water and river water samples.Twenty-seven SVOCs were detected in spring water and 58 in river water,with an average concentration of 631.73 and 16,095 ng/L,respectively.Among the detected SVOCs,PAEs constituted the predominant proportion.This study underscored the presence of SVOCs contamination specifi-cally within the spring water,although SVOCs concentrations in river water were significantly greater than those found in spring water.In summary,this sensitive method based on SPE–GC–MS/MS was successfully developed and validated for the rapid analysis of a diverse array of 256 SVOCs at trace levels in water,including not only the traditional highly valued PAHs,PCBs,pesticides,and PAEs,but also the emerging OPEs,UVs,and SMs.
基金financially supported by the National Natural Science Foundation of China(U22A20421)the Qinglan Project of Jiangsu Province,the 533 Talent Program of Huaian City,and the College Students’Innovative Entrepreneurial Training Plan Program of Jiangsu Province(X202510323027).
文摘Endogenous hydrogen systems,consisting of metal–organic coordination catalysts and alcohols,have been widely applied for the transfer hydrogenation(TH)of biomass-derived carbonyl compounds in recent years.Metal-organic coordination catalysts showed satisfactory ability of TH in the secondary alcohols,but most of them could not effectively employ the cheaper primary alcohols as hydrogen donors.Furthermore,they commonly contained high metal contents,which also led to low catalytic efficiency in significant measure.In this work,we constructed a novel magnesium single-atom catalyst(Mg-NC)with merely 0.37 wt%Mg by means of a combined self-assembly and pyrolysis strategy.The characterization results indicated that Mg was atomically dispersed and it was coordinated with four pyridinic-N in Mg-NC.Due to the obvious electron transfer from Mg to its coordinated pyridinic-N,Mg–N_(4)active centers displayed high Lewis acid-base strength with abundant content,which brought remarkable catalytic activity.When Mg-NC was used for the TH of 5-hydroxymethylfurfural(HMF)in ethanol(EtOH),2,5-bis(hydroxymethyl)furan(BHMF)yield was up to 96.3%with high productivity of 19.85 molBHMF mol_(Mg)^(−1)h^(−1)at 150°C for 5 h.More interestingly,the process of TH over Mg-NC in EtOH was proved to proceed via the hydrogen radical mechanism.Additionally,Mg-NC exhibited powerful catalytic universality;it could not only utilize other primary alcohols(such as n-propanol and n-butanol)as hydrogen donors,but also catalyze the TH of other carbonyl compounds(such as furfural,5-methylfurfural,benzaldehyde,cyclohexanone,and levulinic acid).Overall,this work offered some important clues and references to reinforce the hydrogen-supplying ability of primary alcohols in the TH of various biomass-derived carbonyl compounds to high-value fine chemicals.
基金supported by the Sichuan Provincial Department of Science and Technology(2024ZHCG0086)the Chongqing Science and Technology Commission(cstc2021jscx-cylhX0014).
文摘Chili fermentation is one of the most important processes in the production of Pixian Douban(PXDB),which determines the flavor and product quality of PXDB.However,the maturity of fermented chili mainly depends on empirical judgment,which can not satisfy the need for standardized production of PXDB.Therefore,this study aimed to investigate volatile and non-volatile substances during the maturation process and to find markers related to the maturity of fermented chili.Two-dimensional gas chromatography-mass spectrometry(GC×GC-MS)combined with multivariate statistical analysis and relative odor activity values(ROAV)analysis revealed that 2-methoxy-3-isobutyl pyrazine,linalool,3-(methylthio)propionaldehyde,myrcene,and decanal(ROAV≥1,VIP>1,P<0.05)were regarded as potentially active aromatic markers for differentiating fermentation time.Additionally,ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLCQTOF-MS)combined with multivariate statistical analysis revealed that 25 compounds could serve as differentiated non-volatile compounds.The correlation of maturity-related physicochemical indicators with volatile and nonvolatile compounds revealed that four volatile compounds(2-methoxy-3-isobutylpyrazine,linalool,myrcene,and decanal)along with seven non-volatile compounds could serve as markers for evaluating the maturity of fermented chili.This study is expected to establish a standard for the determination of the maturity the fermented chili and lay the foundation for intelligent production of PXDB.
