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Stabilized carbon radical-mediated three-component functionalization of amino acid/peptide derivatives
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作者 Shaofeng Gong Zi-Wei Deng +1 位作者 Chao Wu Wei-Min He 《Chinese Chemical Letters》 2025年第5期3-4,共2页
Amino acids are the building blocks of proteins and play vital roles in both biological systems and drug development.In recent years,increasing attention has been given to the functionalization of amino acid derivativ... Amino acids are the building blocks of proteins and play vital roles in both biological systems and drug development.In recent years,increasing attention has been given to the functionalization of amino acid derivatives.Since the introduction of therapeutic insulin in the early 20th century,the conjugation of drug molecules with amino acids and peptides has been pivotal in driving advancements in drug discovery and become an integral part of modern medical practice.Currently,over a hundred peptide-drug conjugates have received global approval and are widely used to treat diseases such as diabetes,cancer,chronic pain,and multiple sclerosis.Key technologies for conjugating peptides with bioactive molecules include antibody-drug conjugates(ADCs),peptide-drug conjugates(PDCs),and proteolysis targeting chimeras(PROTACs).Significant efforts have been dedicated to developing strategies for the modification of amino acids and peptides,with particular focus on site-selective C-H alkylation/arylation reactions.These reactions are crucial for synthesizing bioactive molecules,as they enable the precise introduction of functional groups at specific positions,thereby improving the pharmacological properties of the resulting compounds. 展开更多
关键词 stabilized carbon radical mediated functionalization three component reactions therapeutic insulin drug developmentin drug discovery amino acids conjugation drug molecules biological systems
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Prediction,screening,characterization,antioxidant and antihypoxic effects of multi-component zwitterionic cocrystals of dietary flavonoids with picolinic acid
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作者 Yao Zou Difei Gong +6 位作者 Haiguang Yang Hongmei Yu Guorong He Ningbo Gong Lianhua Fang Guanhua Du Yang Lu 《Chinese Chemical Letters》 2025年第9期581-588,共8页
The objective of this study was to predict,screen,synthesize,and investigate cocrystals of poorly soluble flavonoids that are commonly found in dietary supplements with bipolar compound picolinic acid(PA).To improve t... The objective of this study was to predict,screen,synthesize,and investigate cocrystals of poorly soluble flavonoids that are commonly found in dietary supplements with bipolar compound picolinic acid(PA).To improve the efficiency and success rate of experimental screening,two virtual tools based on hydrogen bond propensity(HBP)and modified molecular electrostatic potential(MEP)maps were used.The prediction accuracy of HBP and MEP is 58.82%and 94.11%,respectively,presenting that the MEP model is very powerful in the discovery of pharmaceutical cocrystals.Among the 12 successfully obtained cocrystals,4 single crystals of PA with luteolin(LUT),genistein(GEN),taxifolin(TAX),dihydromyricetin(DHM)were obtained for the first time.Charged-assisted O-H…O and N-H…O hydrogen bonds appear as main hydrogen bonding synthons,and PA adopts a zwitterionic form after cocrystallization.GEN-PA,TAX-PA,and DHM-PA showed higher DPPH'radical-scavenging capacities;LUT-PA and DHM-PA showed higher ABTS^(+)radical-scavenging capacities;GEN-PA and DHM-PA possessed better protective effects on H9c2 cells from hypoxic injury caused by CoCl_(2)than corresponding pure flavonoids. 展开更多
关键词 COCRYSTAL Flavonoid Picolinic acid Dietary supplements ZWITTERIONIC
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Study on Optimization of Ultrasonic Extraction Process for Benzoic Acid as a Harmful Component in Paeonia Iactiflora Pall
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作者 Shangyue Chen Guiming Guo +5 位作者 Gang Chen Yanxin Zhai Jingliang Xie Xu Zhao Mingxue Cai Xuegang Zhou 《Chinese Medicine and Natural Products》 2025年第3期193-198,共6页
Objective To optimize the ultrasonic extraction process for benzoic acid as a harmful substance in Paeonia lactiflora Pall.(P.lactiflora Pall.).Methods Methanol and ethanol solutions at different concentration gradien... Objective To optimize the ultrasonic extraction process for benzoic acid as a harmful substance in Paeonia lactiflora Pall.(P.lactiflora Pall.).Methods Methanol and ethanol solutions at different concentration gradients(25,50,75%)were prepared to investigate the effects of extraction solvents on the extraction efficiency of benzoic acid.The influences of ultrasonic frequency(35,50 Hz),ultrasonic power(40,60,80,100 W),ultrasonic time(10,20,30,40,50,60 minutes),and ultrasonic temperature(20,30,40,50℃)on the extraction efficiency were examined.Orthogonal experiments were conducted to analyze the effects of temperature,time,and ultrasonic power on the extraction efficiency and to screen the optimal ultrasonic extraction process.Results Various influencing factors had certain effects on the extraction efficiency of benzoic acid from P.lactiflora Pall.Single-factor analysis revealed that 25%methanol,ultrasonic frequency of 50 Hz,ultrasonic power of 40 W,ultrasonic time of 10minutes,and ultrasonic temperature of 30℃yielded the highest extraction efficiency for benzoic acid.The order of influence of different factors on the extraction efficiency was temperature>time>power.The optimal conditions obtained from orthogonal experiments were:extraction solvent of 25%methanol,ultrasonic frequency of 50 Hz,ultrasonic time of 20 minutes,ultrasonic power of 40 W,and ultrasonic temperature of 30℃.Conclusion Under the conditions of 25%methanol as the extraction solvent,ultrasonic frequency of 50 Hz,ultrasonic time of 20 minutes,ultrasonic power of 40 W,and ultrasonic temperature of 30℃,the extraction efficiency of benzoic acid from P.lactiflora Pall.was the highest.This method offers advantages such as simple operation,small sample size requirement,and low solvent consumption,providing a reliable analytical approach for quality control and safety evaluation of P.lactiflora Pall. 展开更多
关键词 Paeonia lactiflora Pall. benzoic acid ultrasonic extraction process optimization
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Cavity ring-down spectroscopy CO gas sensor integrating principal component analysis with savitzky-golay filtering
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作者 GUO Zi-long SHI Cheng-rui +4 位作者 DONG Yuan-yuan ZHANG Lei SUN Xiao-yuan SUN Jing-jing ZHOU Sheng 《中国光学(中英文)》 北大核心 2026年第1期179-189,共11页
The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recogni... The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recognized to be limited at data boundaries and high frequencies,which can significantly reduce the signal-to-noise ratio(SNR).To solve this problem,a novel method synergistically integrating Principal Component Analysis(PCA)with SG filtering is proposed in this paper.This approach avoids the is-sue of excessive smoothing associated with larger window sizes.The proposed PCA-SG filtering algorithm was applied to a CO gas sensing system based on Cavity Ring-Down Spectroscopy(CRDS).The perform-ance of the PCA-SG filtering algorithm is demonstrated through comparison with Moving Average Filtering(MAF),Wavelet Transformation(WT),Kalman Filtering(KF),and the SG filter.The results demonstrate that the proposed algorithm exhibits superior noise reduction capabilities compared to the other algorithms evaluated.The SNR of the ring-down signal was improved from 11.8612 dB to 29.0913 dB,and the stand-ard deviation of the extracted ring-down time constant was reduced from 0.037μs to 0.018μs.These results confirm that the proposed PCA-SG filtering algorithm effectively improves the smoothness of the ring-down curve data,demonstrating its feasibility. 展开更多
关键词 cavity ring-down spectroscopy CO gas sensor principal component analysis Savitzky-Golay filter
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Syntheses,structures,and catalytic performances of complexes with 4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid ligands
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作者 LING Weizhong LIN Jingyi +3 位作者 ZHU Jianglin LIANG Yuyi DAI Shanshan LI Yu 《无机化学学报》 北大核心 2026年第1期152-160,共9页
Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(... Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3. 展开更多
关键词 COMPLEX dicarboxylic acid catalytic properties Knoevenagel reaction
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The study on citric acid-modified HUSY catalyzed alkylation of phenol with cyclohexanol
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作者 HUA Canhao WU Jingfeng +2 位作者 ZHU Lingjun XU Guangwen WANG Shurong 《燃料化学学报(中英文)》 北大核心 2026年第3期58-70,共13页
Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylat... Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylation-hydrogenation processes.This study systematically evaluates the catalytic performance of various zeolites(Hβ,HZSM-5,MCM-41 and HUSY)in the alkylation reaction of phenol with cyclohexanol.Characterization results demonstrate that HUSY zeolite showed superior catalytic activity compared to other zeolites,attributable to its favorable pore architecture and well-balanced acid site distribution that synergistically facilitate molecular diffusion and catalytic transformations.To further enhance the catalytic properties,HUSY zeolite was modified with citric acid at various concentrations and compared with those treated with NaOH and oxalic acid.The results revealed that citric acid treatment preserved the crystallinity of the zeolite while modulating its acid distribution and pore structure.All modified zeolites enhanced phenol alkylation activity.Notably,the HUSY-0.5M catalyst,which exhibited the highest medium-strong acid to total acid ratio,achieved superior catalytic performance,80.4%conversion of phenol and 99.6%selectivity for alkylation products.The catalyst also exhibited high activity in the alkylation of various lignin-derived compounds,demonstrating its broad applicability.This work provides a new strategy for the valorization of lignin-derived phenols into high-value fuel precursors through alkylation. 展开更多
关键词 citric acid modification HUSY phenolic alkylation aviation fuel
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Taurodeoxycholic,taurocholic,and glycocholic acids promote hepatic gluconeogenesis via TGR5 in dairy cows
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作者 Miaomiao Zhu Yining Zheng +7 位作者 Shiyang Lou Ruixu Zhang Dingping Feng Xinjian Lei Lei Chen Jianguo Wang Junhu Yao Lu Deng 《Journal of Animal Science and Biotechnology》 2026年第1期500-515,共16页
Background Ruminants and monogastric animals exhibit significant differences in gluconeogenic efficiency.In dairy cows,hepatic gluconeogenesis serves as the primary source of glucose.Metabolites modulate gluconeogenes... Background Ruminants and monogastric animals exhibit significant differences in gluconeogenic efficiency.In dairy cows,hepatic gluconeogenesis serves as the primary source of glucose.Metabolites modulate gluconeogenesis efficiency through allosteric regulation,redox state,and signal transduction pathways.However,the liver-enriched metabolites that regulate hepatic gluconeogenesis in dairy cows and their specific regulatory mechanisms remain incompletely characterized.Results Six Holstein dairy cows and six Duroc×(Landrace×Yorkshire)(DLY)crossbred pigs served as research subjects.Employing non-targeted and targeted metabolomics,we discovered that three bile acids—taurodeoxycholic acid(TDCA),taurocholic acid(TCA),and glycocholic acid(GCA)—were highly enriched in Holstein dairy cows'livers.In bovine hepatocytes,individual or combined stimulation of these bile acids significantly upregulated the expression of gluconeogenesis genes(FBP1,PCK1 and G6PC)and enhanced glucose production.In fasting mice with induced gluconeogenesis,TDCA,TCA,and GCA increased fasting blood glucose levels,and pyruvate tolerance tests further revealed their capacity to enhance hepatic gluconeogenesis,enabling more efficient glucose synthesis from pyruvate.Mechanistically,these bile acids activated Takeda G protein-coupled receptor 5(TGR5),elevated intracellular cAMP levels,and ultimately enhanced gluconeogenesis via the transcription factor cAMP-response element binding protein(CREB).Notably,a TGR5 inhibitor abrogated the stimulatory effects of TDCA,TCA,and GCA on hepatic gluconeogenesis in fasting mice.Conclusion TDCA,TCA,and GCA are key metabolites promoting hepatic gluconeogenesis in dairy cows,with TGR5 as the pivotal receptor and the cAMP/PKA/CREB pathway as the critical downstream mechanism. 展开更多
关键词 cAMP-response element binding protein GLUCONEOGENESIS Glycocholic acid Takeda G protein-coupled receptor 5 Taurocholic acid Taurodeoxycholic acid
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Lysophosphatidic acid signaling:Transmembrane modulators in the central nervous system
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作者 Alexandra Polyzou Alexandros Κ.Tsiouris +2 位作者 Charalampos Labrakakis Britta J.Eickholt George Leondaritis 《Neural Regeneration Research》 2026年第3期1104-1105,共2页
Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,includi... Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018). 展开更多
关键词 transmembrane modulators cerebrospinal fluidvaries variety lipid species lysophosphatidic acid biological fluidsincluding lysophosphatidic acid lpa saturated unsaturated fatty acids pleiotropic lipid agonist
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Study on Active Components from the Stems of Polyalthia plagioneura(II)
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作者 Bingjing LIU Guikun TANG 《Agricultural Biotechnology》 2026年第1期63-64,69,共3页
[Objectives]This study was conducted to isolate and identify the components from stems of Polyalthia plagioneura.[Methods]The compounds were isolated and purified by silica gel column,Sephadex LH-20,and C_(18) chromat... [Objectives]This study was conducted to isolate and identify the components from stems of Polyalthia plagioneura.[Methods]The compounds were isolated and purified by silica gel column,Sephadex LH-20,and C_(18) chromatography.Their chemical structures were elucidated on the basis of physicochemical properties and spectral data.[Results]Five compounds were isolated and identified as:di(2-ethylhexyl)phthalate(1),cinnamic anhydride(2),phthalic acid(3),citric acid(4),and syringaldehyde(5).[Conclusions]All compounds were isolated from this plant for the first time. 展开更多
关键词 Polyalthia plagioneura Chemical component STEROID
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Tetrahedral framework nucleic acids in the prevention and treatment of skin and mucosal diseases:Advances and prospects
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作者 Yuge Zhang Siqi Xu +4 位作者 Chenpeng Chen Haiyu Xian Qitao Wen Yunfeng Lin Tao Wang 《Chinese Chemical Letters》 2026年第2期135-144,共10页
The application of DNA hybridization technology,grounded in Watson-Crick base pairing,has facilitated the rational design of framework nucleic acids(FNAs)featuring adaptable shapes and dimensions.These nanostructures ... The application of DNA hybridization technology,grounded in Watson-Crick base pairing,has facilitated the rational design of framework nucleic acids(FNAs)featuring adaptable shapes and dimensions.These nanostructures exhibit remarkable stability and reproducibility,making them promising candidates for biomedical applications.Among various FNAs,tetrahedral FNAs(tFNAs),first introduced by Turberfield,are nanoscale assemblies of oligonucleotides that possess unique physical,chemical,and biological properties.Previous studies have demonstrated that tFNAs exhibit excellent cellular uptake,enhanced tissue permeability,and strong capabilities to promote cell migration,proliferation,and differentiation.Moreover,the intrinsic ability of tFNAs to efficiently penetrate cell membranes allows tFNAs to serve as versatile carriers for small-molecule drugs or functional oligonucleotides,thereby exerting significant anti-inflammatory,antioxidant,antibacterial,and immunomodulatory effects.These features highlight the therapeutic potential of tFNA-based complexes in skin,mucosal,and barrier tissue repair and regeneration.This review provides a comprehensive analysis of recent advances in the application of tFNAs for the prevention and treatment of skin,mucosal,and barrier tissue diseases,with a focus on their mechanisms of action and future prospects in regenerative medicine and targeted therapies. 展开更多
关键词 Tetrahedral framework nucleic acids DNA nanomaterials Nucleic acid drugs Skin repair and regeneration Mucosal lesions
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Microstructure and properties of HPDC AM60 based alloys for super-sized integrated automotive components
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作者 Jing WANG Xin GUO +8 位作者 Jiang-feng SONG Dang-he SHI He-cong XIE Chun-yu LI Heng-rui HU Gong CHEN Bin JIANG Dong-xia XIANG Fu-sheng PAN 《Transactions of Nonferrous Metals Society of China》 2026年第2期433-450,共18页
The commercial AM60(Mg−6Al−0.3Mn)die-casting alloy was modified through Mn,Ce,and La micro-alloying,each at a content below 0.2 wt.%.SEM,TEM,and Micro-CT were employed to characterize the microstructures and propertie... The commercial AM60(Mg−6Al−0.3Mn)die-casting alloy was modified through Mn,Ce,and La micro-alloying,each at a content below 0.2 wt.%.SEM,TEM,and Micro-CT were employed to characterize the microstructures and properties of AM60 based alloys.AM60-0.2La alloy showed excellent mechanical properties.The ultimate tensile strength,yield strength,and elongation of(288.0±1.7)MPa,(158.0±1.0)MPa,and(22.0±3.0)%were achieved in AM60-0.2La alloy.Besides,AM60-0.2La alloy exhibited the best corrosion resistance(0.29 mm/a)and fluidity among the investigated four alloys.The excellent mechanical properties and corrosion resistance are mainly attributed to the grain refinement strengthening,low porosity,and low content of large shrinkage porosity,promising for super-sized integrated automotive components. 展开更多
关键词 magnesium alloys microstructure mechanical properties high-pressure die-casting integrated automotive components
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Comprehensive quality evaluation and principal component analysis of Crassostrea gigas from North Yellow Sea,China:characterizing nutritional,flavor,and functional profiles
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作者 Shanqin HUO Jixing PENG +3 位作者 Xinnan ZHAO Yichen LIN Xudong LI Zhijun TAN 《Journal of Oceanology and Limnology》 2026年第1期406-418,共13页
Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characte... Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characteristics of C.gigas from different sources(ploidy,region,size,and culture mode),C.gigas from various ploidy(diploid and triploid),regions(Rushan,Off-site fattening,and Rongcheng),sizes(small,medium,and large)and culture modes(nearshore and offshore)were selected for comparative analyses.The nutritional components(moisture,protein,fat,and mineral),flavor substances(taste amino acids,nucleotides,and succinic acid),and functional indices(eicosapentaenoic acid(EPA),docosahexaenoic acid(DHA),and taurine)of C.gigas were determined.Principal component analysis(PCA)was used to comprehensively evaluate the oysters and investigate the variations in nutritional quality.The PCA results indicate that protein,essential fatty acids,selenium,zinc,taste amino acids,taurine,EPA,and DHA were core components contributing to 82.25%of the cumulative variance,providing a more comprehensive reflection of the nutrient composition of C.gigas.The extensive quality rankings for the C.gigas were as follows:diploid>triploid,Rushan>fattening>Rongcheng,medium>large>small,and offshore>nearshore.The score rank revealed that diploid oysters of medium-size from Rushan demonstrated superior nutritional quality compared to other tested samples.This is the first comprehensive and systematic investigation of C.gigas in northern China to reveal the feature of nutrients,flavor,and functional components.The study provided data support for the culture,consumption,processing,research,and nutritional quality improvement of oyster industry. 展开更多
关键词 Crassostrea gigas nutritional quality principal component analysis comprehensive evaluation
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Multi-pass intermittent local loading process of large-scale rib-web component:Forming characteristics and implementing apparatus
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作者 Dawei ZHANG Peng DONG +2 位作者 Jingxiang LI Zijian YU Shengdun ZHAO 《Chinese Journal of Aeronautics》 2026年第1期601-625,共25页
The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and redu... The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and reduce forming loads.However,the absence of compatible forming equipment makes it difficult to control the constraint in the unloaded zones during the forming process.This difficulty complicates coordination and control of deformation,particularly for asymmetric rib-web components.Additionally,the current implementation involves multi-fire heating,a long process flow,and high energy consumption,which limits the popularization and application of the local loading process.In this study,a new multi-pass local loading hydraulic forming apparatus that can quickly and reliably switch between heavy-load deformation and low-load constraint for different local loading sub-dies was developed.A 10-tonne laboratory prototype was developed,and the forming characteristics during the forming process as well as the response characteristics of the hydraulic system during the multi-pass intermittent local loading of rib-web component were investigated using numerical simulations and physical experiments.Results indicated that,compared to a whole loading process with the same initial geometry of billet,the total forming load(i.e.,the sum of loaded and restrained loads)is reduced by more than 40%with the local loading process,and by nearly 50%with multi-pass local loading.The multi-pass local loading process allows for more effective control of material flow compared to single-pass local loading,leading to improved cavity filling and reduced flow line disturbance.For a large-scale,complex titanium alloy bulkhead,the cavity filling problem was addressed by optimizing the multi-pass local loading path with an unequal thickness billet.The dynamic performance of the multi-pass local loading hydraulic system was found to be robust,with stable pressure transitions during motion and load switching for the sub-die(s).The dynamic characteristic of the hydraulic cylinder when switching from non-moving/unloaded state to a moving/loading state are consistent whether a load is present or not.However,the dynamic characteristics differ when switching from a moving/loading state to non-moving/unloaded state,showing opposite behavior.The developed hydraulic drive mechanism provides a way for implementation of multi-pass local loading without auxiliary operation and extra heating.The results of the study provide a foundation for the industrial production of large-scale,complex components with reduced force requirement and low-energy consumption. 展开更多
关键词 Forming characteristics Hydraulic system Intermittent local loading process Material flow Rib-web component
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Natural novel vitamin C derivative,2-O-β-D-glucopyranosyl-L-ascorbic acid:Resources,biosynthesis,and applications
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作者 Mengyue Wang Haotian Wu +7 位作者 Li Xiang Ranran Gao Qinggang Yin Yang Chu Lan Wu Yanyan Su Gangqiang Dong Yuhua Shi 《Chinese Herbal Medicines》 2026年第1期77-88,共12页
As the only naturally occurring stable derivative of L-ascorbic acid(AA;vitamin C),2-O-β-D-glucopyranosyl-L-ascorbic acid(AA-2βG)is hydrolyzed in vivo to release active AA.AA-2βG exhibits strong antioxidant and ant... As the only naturally occurring stable derivative of L-ascorbic acid(AA;vitamin C),2-O-β-D-glucopyranosyl-L-ascorbic acid(AA-2βG)is hydrolyzed in vivo to release active AA.AA-2βG exhibits strong antioxidant and antiphotoaging effects comparable to those of AA,and it plays a key role in maintaining organismal health.Owing to its superior stability and bioavailability,AA-2βG is considered as a promising,longer-lasting natural alternative to conventional vitamin C.It was first identified and is particularly abundant in Lycii Fructus(Gouqizi in Chinese)but has been detected in several crop plants.This review offers a comprehensive overview of recent advances in AA-2βG research,covering key aspects including discovery,structure,natural sources,extraction and detection methods,chemical and in vitro enzymatic synthesis,biosynthetic pathways,as well as applications in health care,skin care,and functional foods.Additionally,we highlight strategies for leveraging plant resources and enhancing AA-2βG biosynthesis,which are expected to accelerate future research and support the sustainable development and utilization of AA-2βG and other high-value natural products. 展开更多
关键词 2-O-β-D-glucopyranosyl-L-ascorbic acid ascorbic acid derivative Lycii Fructus Lycium barbarum L. Lycium chinense Mill. natural products vitamin C
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Insights into the organic acid and flavonoid metabolisms in moderately withered blueberries based on metabolomics and transcriptomics
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作者 Qin Yang Haijun Bi +6 位作者 Qi Zhang Shuqin Huang Chen Bian Lulu Zhao Hongbin Chen Xueling Gao Yu Wang 《Journal of Future Foods》 2026年第6期1155-1165,共11页
This study employed integrated metabolomic and transcriptomic analyses to investigate the impacts of moderate withering(approximately 30%weight loss)on organic acid and flavonoid accumulation in blueberries and the re... This study employed integrated metabolomic and transcriptomic analyses to investigate the impacts of moderate withering(approximately 30%weight loss)on organic acid and flavonoid accumulation in blueberries and the resultant blueberry wines.Moderate withering led to decreases in aliphatic organic acids but increases in phenolic acids and flavonoids in blueberries.The decrease in malate could be linked to the downregulated VcMDH and VcDTC,and the decrease in citrate and 2-oxoglutarate could be a consequence of y-aminobutyric acid shunt activation.The increases of phenolic acids were associated with upregulated VcCAD and VcPOD in withered blueberries.Additionally,moderate withering upregulated the expression of VcLAR and VcUFGT,promoting flavonoid accumulation.In blueberry wines,moderate withering decreased total aliphatic organic acid content but increased anthocyanin content,consistent with the findings in blueberries.Overall,this study provided references for applying moderate withering in blueberry winemaking,contributing to modulating acidity and enriching phenolic substances. 展开更多
关键词 BLUEBERRY Moderate withering Wine Organic acids Flavonoids
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Two-Stage LightGBM Framework for Cost-Sensitive Prediction of Impending Failures of Component X in Scania Trucks
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作者 Si-Woo Kim Yong Soo Kim 《Computers, Materials & Continua》 2026年第3期1222-1240,共19页
Predictive maintenance(PdM)is vital for ensuring the reliability,safety,and cost efficiency of heavyduty vehicle fleets.However,real-world sensor data are often highly imbalanced,noisy,and temporally irregular,posing ... Predictive maintenance(PdM)is vital for ensuring the reliability,safety,and cost efficiency of heavyduty vehicle fleets.However,real-world sensor data are often highly imbalanced,noisy,and temporally irregular,posing significant challenges to model robustness and deployment.Using multivariate time-series data from Scania trucks,this study proposes a novel PdM framework that integrates efficient feature summarization with cost-sensitive hierarchical classification.First,the proposed last_k_summary method transforms recent operational records into compact statistical and trend-based descriptors while preserving missingness,allowing LightGBM to leverage its inherent split rules without ad-hoc imputation.Then,a two-stage LightGBM framework is developed for fault detection and severity classification:Stage A performs safety-prioritized fault screening(normal vs.fault)with a false-negativeweighted objective,and Stage B refines the detected faults into four severity levels through a cascaded hierarchy of binary classifiers.Under the official cost matrix of the IDA Industrial Challenge,the framework achieves total misclassification costs of 36,113(validation)and 36,314(test),outperforming XGBoost and Bi-LSTM by 3.8%-13.5%while maintaining high recall for the safety-critical class(0.83 validation,0.77 test).These results demonstrate that the proposed approach not only improves predictive accuracy but also provides a practical and deployable PdM solution that reduces maintenance cost,enhances fleet safety,and supports data-driven decision-making in industrial environments. 展开更多
关键词 Predictive maintenance two-stage classification cost-based evaluation LightGBM scania component X dataset
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Taurochenodeoxycholic acid promotes abdominal fat deposition by modulating the crosstalk between bile acid metabolism and intestinal microbiota in broilers
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作者 Xi Sun Chaohui Wang +4 位作者 Xiaoying Liu Yun Li Zhouzheng Ren Xiaojun Yang Yanli Liu 《Journal of Animal Science and Biotechnology》 2026年第1期531-545,共15页
Background The role of bile acids in modulating the gut microbiota and their impact on host metabolism has garnered significant attention.Taurochenodeoxycholic acid(TCDCA)is the predominant bile acid within the chicke... Background The role of bile acids in modulating the gut microbiota and their impact on host metabolism has garnered significant attention.Taurochenodeoxycholic acid(TCDCA)is the predominant bile acid within the chicken bile acid pool and is closely related to metabolic disorders.The current study aims to investigate the potential effects of TCDCA on abdominal fat deposition in broilers.From 14 to 28 days of age,the broilers in the CON group received an oral administration of 1 mL of saline,while those in the treatment groups were administered 1 mL of a solution containing 0.05 g,0.10 g,or 0.20 g of TCDCA.Results The results showed that TCDCA treatments from 14 to 28 d had no significant effects on BW,ADFI,ADG and FCR in broilers at the age of 28 days of age.However,the abdominal fat percentage in the 0.20 g TCDCA group significantly increased,accompanied by higher TBA and HDL-c levels,as well as a reduction in apolipoprotein B levels in serum.In addition,serum triglyceride levels tended to be higher in the 0.20 g TCDCA group(P=0.098).The 0.20 g TCDCA treatment increased the gene expressions of SREBP-1,C/EBP-α,and ELOVL6,while decreasing the mRNA abundance of ATGL and CPT-1 in the abdominal fat.Serum levels of TCDCA,TDCA,and THDCA were significantly higher after 0.20 g TCDCA administration,while TCA levels were significantly lower,as determined by the targeted bile acid metabolomics analysis.Conversely,hepatic mRNA levels of CYP7A1,CYP27A1,BAAT,and BSEP were increased in the 0.20 g TCDCA group.The oral administration of 0.20 g TCDCA also upregulated the expression of FXR,VDR,and FGF19 in abdominal fat.The 16S rRNA analysis of cecal microbiota revealed that a decrease in the Shannon and Simpson indexes in the 0.20 g TCDCA group,and an increase in the Firmicutes/Bacteroidetes ratio.LEfSe analysis revealed that the predominant bacteria in the CON group were Streptococcus and Oscillospira at the genus level,while Lactobacillus,Parabacteroides,Anaeroplasma,and Helicobacter were identified as the dominant genera in the 0.20 g TCDCA group.Functional predictions for the gut microbiota exhibited that lipid metabolism,replication and repair pathway were enhanced in the 0.20 g TCDCA group.Correlation analysis demonstrated that the abundance of Lactobacillus was positively correlated with serum levels of TCDCA,THDCA,and TDCA,while the abundance of Streptococcus and Oscillospira showed a positive correlation with serum TCA levels.Conclusion Overall,this study elucidates that the intervention of 0.20 g TCDCA may promote abdominal fat deposition by activating bile acid receptors in abdominal fat,and concurrent alterations in both the intestinal microbial community and bile acid profile. 展开更多
关键词 Abdominal fat BROILER Cecal microbiota Taurochenodeoxycholic acid
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Transition metal-catalyzed C-H activation/annulation for the construction of unnatural amino acids and peptides
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作者 Xiao Tang Erik V.Van der Eycken Liangliang Song 《Chinese Chemical Letters》 2026年第2期191-205,共15页
Peptides play important roles in chemistry,medicinal chemistry and life science,due to their high efficiency and specificity,unusual biological and therapeutic properties.As naturally occurring peptides often face wit... Peptides play important roles in chemistry,medicinal chemistry and life science,due to their high efficiency and specificity,unusual biological and therapeutic properties.As naturally occurring peptides often face with their intrinsic limitations including metabolic instability and low membrane permeability,the strategies for synthesizing unnatural amino acids and peptides are explored.Among the methods for modifying amino acids and peptides,chemo-and site-selective approaches are preferred because of the ability to fine-tuning structural features.Recently,transition metal-catalyzed Csingle bondH activation has been employed for the functionalization of amino acids and peptides.Through domino Csingle bondH activation/annulation,a series of structurally complex and diverse amino acids and peptides is constructed.This review highlights recent advances in the synthesis of unnatural amino acids and peptides via transition metal-catalyzed Csingle bondH activation/annulation. 展开更多
关键词 Amino acid PEPTIDE Transition metal C-H activation ANNULATION
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Saturated Alcohols Electrocatalytic Oxidations on Ni-Co Bimetal Oxide Featuring Balanced B-and L-Acidic Active Sites
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作者 Junqing Ma Wenshu Luo +9 位作者 Xunlu Wang Xu Yu Jiacheng Jayden Wang Huashuai Hu Hanxiao Du Jianrong Zeng Wei Chen Minghui Yang Jiacheng Wang Xiangzhi Cui 《Nano-Micro Letters》 2026年第2期105-123,共19页
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro... Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts. 展开更多
关键词 Solid-acid electrocatalyst Alcohol oxidation reaction Bronsted acid sites Lewis acid sites C_(1)-C_(6)saturated alcohols
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Unbalanced lipid metabolism in anther,especially the disorder of the alpha-linolenic acid metabolism pathway,leads to cotton male sterility
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作者 Lihong Ma Pengtao Wang +7 位作者 Qian-Hao Zhu Xinqi Cheng Tao Zhang Xinyu Zhang Huaguo Zhu Zuoren Yang Jie Sun Feng Liu 《Journal of Integrative Agriculture》 2026年第2期610-623,共14页
Recent studies have shown that lipid metabolism is a key factor affecting anther development and male fertility.However,how plants regulating the metabolic balance of multiple lipids to ensure proper anther developmen... Recent studies have shown that lipid metabolism is a key factor affecting anther development and male fertility.However,how plants regulating the metabolic balance of multiple lipids to ensure proper anther development and male fertility remains unclear.Analyzing lipid molecules related to anther fertility and genes responsible for their biosynthesis is crucial for understanding the physiological significance of lipid metabolism in crop fertility.In this study,we compared the transcriptome and the composition and content of lipids in anthers of two upland cotton(Gossypium hirsutum) materials,Shida 98(WT) and its nearly-isogenic male sterile line Shida 98A(MS).Transcriptomics analysis identified many differentially expressed genes(DEGs) between the two materials,with the genes of the alpha-linolenic acid metabolism pathway being the most significantly associated with the male sterility phenotype.Investigations on lipids revealed that the MS anthers over-accumulated free fatty acids(FFAs),phosphatidic acid(PA),mono-and di-galactosyldiacylglycerol(MGDG and DGDG),and had a decreased content of triacylglycerol(TAG),which was closely related to the abnormal metabolism of alpha-linolenic acid(C18:3);therefore,the major lipids containing C18:3-acyl chains,such as PA,MGDG,DGDG,and TAG,are proposed to play a major role in cotton anther development.We also showed that an excessive level of MGDG and DGDG caused jasmonic acid(JA) overaccumulation in MS anthers,which in turn inhibited the expression of GhFAD3 and consequently reduced the C18:3 content,presumably via a feedback regulation mechanism,ultimately affecting plant fertility.Together,our results revealed the importance of a balanced lipid metabolism in regulating the development of cotton anther and pollen and consequently male fertility. 展开更多
关键词 COTTON ANTHER male sterility lipid metabolism alpha-linolenic acid
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