Transcutaneous electrical acupoint stimulation(TEAS)is a kind of physical therapy that use electric cur-rent through the electrodes placed on the surface of acupoints to produce clinical effects in the human body,whic...Transcutaneous electrical acupoint stimulation(TEAS)is a kind of physical therapy that use electric cur-rent through the electrodes placed on the surface of acupoints to produce clinical effects in the human body,which is characterized by less adverse reaction and convenient operation.It has been widely used in the treatment of various diseases.This review introduces six major clinical applications of TEAS,named analgesia,regulation of gastrointestinal function,improvement of reproductive function,enhancement of cognitive function,promotion of limb function recovery and relief of fatigue.Besides,TEAS has been ap-plied to the treatment of other chronic diseases such as hypertension and diabetes,achieving satisfactory clinical effects.However,two crucial challenges are encountered in the development of TEAS.One is the lack of standardization in the selection of parameters such as waveform,frequency,intensity and stimula-tion duration.The other is the limitation on the flexibility in the acupoint selection.This review analyzes key issues that need to be addressed in the current clinical application of TEAS,such as the selection of parameters and acupoints,and this review provides a certain reference value for optimizing regimens of TEAS and promoting its development and application.展开更多
Currently,cultivated tea plants are classified into three varieties,namely,Camellia sinensis var.sinensis,C.sinensis var.assamica,and C.sinensis var.kucha.Three tea varieties made green teas(TVGTs)are widely consumed ...Currently,cultivated tea plants are classified into three varieties,namely,Camellia sinensis var.sinensis,C.sinensis var.assamica,and C.sinensis var.kucha.Three tea varieties made green teas(TVGTs)are widely consumed worldwide.However,a comparative investigation of the beneficial effects,mechanism,and characteristic compounds of TVGTs has not been reported.Here,three representative tea plant varieties,namely,C.sinensis var.sinensis cv.Fuding(FD),C.sinensis var.assamica cv.Yunkang 10(YK),and C.sinensis var.kucha(KC),planted in the same garden,were used to make green teas utilizing the same standard procedure.Our findings show that the TVGTs effectively improved hyperglycemia,obesity,dyslipidemia,fatty liver,and mesenteric artery(MA)hypercontractility in mice with diabetes and obesity induced by a high-fat diet(HFD)after 11-and 22-week interventions,with YK being the most effective at 22 weeks.Liver lipidomics indicated that the TVGTs restored the glycerophospholipid and sphingolipid balance and reduced triglycerides,with YK demonstrating superior effects.The TVGTs,particularly YK,suppressed triglyceride synthesis through the ARV1-FXR-SHP-SREBP-1c pathway.A chemical profile analysis revealed that YK green tea had enriched active compounds,including caffeine,quinic acid,L-theanine,gallic acid,and catechins,compared with FD and KC green teas,which may contribute to ameliorating diabetic dyslipidemia via synergistic action.As a representative tea variety of C.sinensis var.assamica,YK green tea was found to be superior to the other two green teas in preventing and treating diabetic dyslipidemia,especially with long term consumption.These data provide important information for tea plant breeders and tea consumers.展开更多
On the stone-paved lanes of Songyang County that date back to ancient times,morning mist lingered as a faint fragrance of tea wafted from a century-old house.Inside,Yang Junjie,a tea maker born in the 1980s,worked def...On the stone-paved lanes of Songyang County that date back to ancient times,morning mist lingered as a faint fragrance of tea wafted from a century-old house.Inside,Yang Junjie,a tea maker born in the 1980s,worked deftly at the stove,his hands moving swiftly over the scorching iron wok as tender green tea leaves dance between his fingers.展开更多
Blending tradition with modern elements,Songyang’s tea industry attracts young entrepreneurs to revive culture and drive economic growth.SONGYANG has a long and rich history of tea cultivation and production.The coun...Blending tradition with modern elements,Songyang’s tea industry attracts young entrepreneurs to revive culture and drive economic growth.SONGYANG has a long and rich history of tea cultivation and production.The county became famous for its tea as early as the Three Kingdoms period(220-280).Today,this land is home to over 10,000 hectares of ecofriendly tea plantations.One in every three Songyang residents is involved in the tea industry,whose full industrial chain value now exceeds RMB 13.5 billion.展开更多
Paying an additional RMB 2 could have your next milk tea delivered by drone to your balcony in just five minutes.This small fee represents the vast potential of the trillion-yuan lowaltitude economy.
Vine tea is documented in ancient Chinese books as having the function of promoting blood circulation.However,its effects and mechanisms remain unclear.The aim of this study was to comprehensively investigate the prot...Vine tea is documented in ancient Chinese books as having the function of promoting blood circulation.However,its effects and mechanisms remain unclear.The aim of this study was to comprehensively investigate the protective potential and mechanisms of vine tea in high-fat diet rat through a combination of in vivo and in vitro experiments.The efficacy of vine tea was evaluated using a high-fat diet rat model and an oxidized low-density lipoprotein-treated cell model,with physiological and biochemical indicators measured in rat serum and cell supernatants.Transcriptomics was utilized to investigate alterations mRNA expression following the administration of dihydromyricetin in cell model.Metabolomics and 16S rRNA sequencing was employed to examine changes in metabolites in the serum and changes in gut microbiota of high-fat diet rats after administering vine tea extract.Vine tea extract and dihydromyricetin can reduce elevated levels of lipids,including total cholesterol and triglycerides,following modeling.Transcriptomic data indicate that dihydromyricetin exerts its effects by regulating ferroptosis signaling pathways.Metabolomic analysis demonstrates that the administration of vine tea extract influences the vitamin K cycle and glutathione,thereby alleviating the progression of ferroptosis.Additionally,16S rRNA sequencing reveals that vine tea extract increases Lactobacillaceae in the gut microbiota,which subsequently affects the levels of lysophosphatidylcholine,a major phospholipid component of oxidized low-density lipoprotein in serum.Our results indicate that vine tea can regulate ferroptosis signaling pathways and increase Lactobacillaceae in the gut microbiota,thereby exhibiting cardiovascular protective effects in high-fat diet rats.展开更多
Understanding the molecular responses of tea leaves to mechanical stress is crucial for elucidating the mechanisms of post-harvest quality formation during oolong tea processing.This study employed an integrated multi...Understanding the molecular responses of tea leaves to mechanical stress is crucial for elucidating the mechanisms of post-harvest quality formation during oolong tea processing.This study employed an integrated multi-omics strategy to characterize the changes and interactions among metabolomic(MB),transcriptomic(TX),and proteomic(PT)profiles in mechanically stressed tea leaves.Mechanical stress initially activated damage-associated molecular patterns(DAMPs),including Ca^(2+)signaling,jasmonic acid signaling,and glutathione metabolism pathways.These processes subsequently induced quality-related metabolic pathways(QRMPs),particularly α-linolenic acid and phenylalanine metabolism.Upregulated expression of LOX,ADH1,and PAR genes,together with the increased abundance of their encoded proteins,respectively promoted the accumulation of jasmine lactone,benzyl alcohol,and 2-phenylethanol.These findings indicate that mechanical stress influences the metabolite biosynthesis in tea leaves through coordinated molecular responses.This study provides new insights into the molecular mechanisms underlying tea leaf responses to mechanical stress and a foundation for future investigations into how early molecular events may contribute to post-harvest metabolic changes during oolong tea processing.展开更多
Tea plant(Camellia sinensis(L.)O.Kuntze)is a cold-sensitive leaf-harvesting crop whose growth,yield,and processed tea quality are all inhibited by low temperatures.Therefore,identifying the regulatory genes involved i...Tea plant(Camellia sinensis(L.)O.Kuntze)is a cold-sensitive leaf-harvesting crop whose growth,yield,and processed tea quality are all inhibited by low temperatures.Therefore,identifying the regulatory genes involved in tea plant growth and freezing tolerance is crucial for genetic improvement.WRKY transcription factors regulate various plant processes,including growth and development,stress responses,and metabolite biosynthesis.However,the molecular network through which WRKY coordinates these pathways in tea plants remains unclear.In this study,we revealed that CsWRKY57L,a cold-inducible WRKY IIc subfamily member,positively regulated freezing tolerance by directly promoting flavonoid accumulation in tea plants.Transient suppression of CsWRKY57L weakened the freezing tolerance of tea plants by reducing flavonoid content and suppressing the C-repeat-binding factor(CBF)-cold-responsive(COR)gene pathway.In contrast,heterologous overexpression of CsWRKY57L in Arabidopsis had the opposite effect.Additionally,overexpression of CsWRKY57L inhibited reproductive development and accelerated senescence in Arabidopsis.Interaction analysis revealed that CsWRKY57L directly binds to the promoters of CsSWEET1a,CsSWEET15,and AtSWEET15,which encode sugar transporters essential for plant reproductive development,and inhibits their transcription.Overall,the study revealed a dual role of CsWRKY57L in promoting freezing tolerance via flavonoid biosynthesis and inhibiting reproductive development by regulating SWEETs expression.This study uncovers a novel mechanism whereby CsWRKY57L coordinately regulates both stress responses and growth in tea plants,providing a molecular basis for breeding low-temperature-tolerant varieties with restricted reproductive development.展开更多
Litter decomposition is an essential ecosystem process influenced by multiple factors,including substrate quality,climate,edaphic environment,and decomposer communities.However,the role of canopy species identity and ...Litter decomposition is an essential ecosystem process influenced by multiple factors,including substrate quality,climate,edaphic environment,and decomposer communities.However,the role of canopy species identity and diversity on leaf litter decomposition in forests remains understudied.By controlling for macroclimate,soil properties,and litter substrate in a mature common garden,we investigated whether a three-month tea bag incubation of standardized green and rooibos tea substrate is driven by canopy tree species characteristics and diversity.Our study hypothesized two primary pathways:a chemical engineering effect,where trees alter soil properties and decomposer communities through litter input,and a physical engineering effect,where tree canopy structure modulates the local microclimate.The results showed that even under uniform macroclimatic and initial soil conditions,mass loss rates varied widely for green tea(27.4%–73.2%)and rooibos tea(6.1%–34.7%),comparable as found in other research between distinct biomes.While substrate quality was the dominant factor,both engineering pathways and,to a minor extent,tree diversity modulated mass losses.For green tea,tree chemical and physical characteristics seemed equally important,while the physical environment showed an increased importance for rooibos.Incubation depth played a key role,where forest floor decomposition rates are more susceptible to temporal climate variations,and soil-layer decomposition rates are less susceptible to climate variations and more determined by tree species identity.Our findings suggest that tea bag experiments focusing solely on topsoil burial may underestimate processes in the forest floor and the mineralorganic boundary layer.This study underscores the critical role of litter substrate quality in decomposition while demonstrating that tree community composition and the associated herbaceous layer,through both chemical and physical engineering pathways,strongly modulate decomposition rates.展开更多
Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry...Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) was developed to simultaneously determine 11 amino acids in different types of tea (green teas, Oolong tea, black tea and Pu-erh tea). The separation conditions for the analysis of the selected amino acids including the column type, temperature and backpressure as well as the type of additive, were carefully optimized. The best separation of the 11 amino acids was obtained by adding water (5%, v/v) and trifluoroacetic acid (0.4%, v/v) to the organic modifier (methanol). Finally, the developed SFC-MS method was fully validated and successfully applied to the determination of these amino acids in six different tea samples. Good linearity (r ≥ 0.993), precision (RSDs≤ 2.99%), accuracy (91.95%-107.09%) as well as good sample stability were observed. The limits of detection ranged from 1.42 to 14.69 ng/mL, while the limits of quantification were between 4.53 and 47.0 ng/mL. The results indicate that the contents of the 11 amino acids in the six different tea samples are greatly influenced by the degree of fermentation. The proposed SFC-MS method shows a great potential for further investigation of tea varieties.展开更多
The objective of this study was to investigate the geographical origin of Chinese teas using carbon and nitrogen stable isotope ratio technology.The results showed that inter-provincial dispersion of teas in Guangdong...The objective of this study was to investigate the geographical origin of Chinese teas using carbon and nitrogen stable isotope ratio technology.The results showed that inter-provincial dispersion of teas in Guangdong(GD),Guangxi(GX),Hainan(HA),Fujian(FJ),Shandong(SD),Sichuan(SC),Chongqing(CQ),and Henan(HN) provinces was high,while in Zhejiang(ZJ),Hubei(HB),Yunnan(YN),and Anhui(AH) provinces,it was low.Tea samples from GD,GX,HA,and FJ provinces were clustered in one group and separated from those from AH and HB provinces.Thus,carbon and nitrogen stable isotope ratio technology could discriminate teas from among some provinces of China,but not from among others.Better separation might be obtained with a combination of isotopic ratios and other indexes,such as elemental data and organic components.展开更多
Teasing can be approached as a linguistic resource for examining the interpersonal issues of im/politeness and face,or as a discursive strategy for displaying relationships or constructing social identities.However,st...Teasing can be approached as a linguistic resource for examining the interpersonal issues of im/politeness and face,or as a discursive strategy for displaying relationships or constructing social identities.However,studies have underestimated the discursive constraints of teasing in specific contexts.Meanwhile,a majority of teasing studies were based on Western cultures and did not pay sufficient attention to the variety of teasing across cultures.By collecting data from two Chinese entertainment interviews,where the interviewer employs teasing frequently for performing institutional roles,this study examined how teasing functions to assist the interviewer to complete communicative goals,and explored the discursive constraints of teasing in media context.Data analysis exemplified how teasing helped the interviewer to manage an interview event,obtain the vip’s disclosure and seek audience involvement,helping to construct the interviewer’s professionality.Implications for understanding the discursive features of teasing in the Chinese media context were addressed.展开更多
基金Supported by Shanghai 2020“Science and Technology Innovation Action Plan”Medical Innovation Research Special Program:20Y21902800Shanghai Municipal Health Commission Shanghai Three-Year Action Plan to Further Accelerate the Development of Traditional Chinese Medicine Inheritance and Innovation:ZY(2021-2023)−0302)+1 种基金Shanghai Key Specialty(Acupuncture)Construction Project:shslczdzk04701Shanghai 2024"Science and Technology Innovation Action Plan"star cultivation(Sail special):24YF2740600.
文摘Transcutaneous electrical acupoint stimulation(TEAS)is a kind of physical therapy that use electric cur-rent through the electrodes placed on the surface of acupoints to produce clinical effects in the human body,which is characterized by less adverse reaction and convenient operation.It has been widely used in the treatment of various diseases.This review introduces six major clinical applications of TEAS,named analgesia,regulation of gastrointestinal function,improvement of reproductive function,enhancement of cognitive function,promotion of limb function recovery and relief of fatigue.Besides,TEAS has been ap-plied to the treatment of other chronic diseases such as hypertension and diabetes,achieving satisfactory clinical effects.However,two crucial challenges are encountered in the development of TEAS.One is the lack of standardization in the selection of parameters such as waveform,frequency,intensity and stimula-tion duration.The other is the limitation on the flexibility in the acupoint selection.This review analyzes key issues that need to be addressed in the current clinical application of TEAS,such as the selection of parameters and acupoints,and this review provides a certain reference value for optimizing regimens of TEAS and promoting its development and application.
基金financially supported by the National Key Research and Development Program of China(2021YFD1601102)by a key joint grant for regional innovation from the National Natural Science Foundation of China(U19A2034)+2 种基金a key grant for University Synergy Innovation Program of Anhui Province(GXXT-2019-49)a grant from the China Agriculture Research System of MOF and MARA(CARS-19)a grant for supporting an animal core facility in Anhui Agricultural University from the Department of Sciences and Technology of Anhui Province.
文摘Currently,cultivated tea plants are classified into three varieties,namely,Camellia sinensis var.sinensis,C.sinensis var.assamica,and C.sinensis var.kucha.Three tea varieties made green teas(TVGTs)are widely consumed worldwide.However,a comparative investigation of the beneficial effects,mechanism,and characteristic compounds of TVGTs has not been reported.Here,three representative tea plant varieties,namely,C.sinensis var.sinensis cv.Fuding(FD),C.sinensis var.assamica cv.Yunkang 10(YK),and C.sinensis var.kucha(KC),planted in the same garden,were used to make green teas utilizing the same standard procedure.Our findings show that the TVGTs effectively improved hyperglycemia,obesity,dyslipidemia,fatty liver,and mesenteric artery(MA)hypercontractility in mice with diabetes and obesity induced by a high-fat diet(HFD)after 11-and 22-week interventions,with YK being the most effective at 22 weeks.Liver lipidomics indicated that the TVGTs restored the glycerophospholipid and sphingolipid balance and reduced triglycerides,with YK demonstrating superior effects.The TVGTs,particularly YK,suppressed triglyceride synthesis through the ARV1-FXR-SHP-SREBP-1c pathway.A chemical profile analysis revealed that YK green tea had enriched active compounds,including caffeine,quinic acid,L-theanine,gallic acid,and catechins,compared with FD and KC green teas,which may contribute to ameliorating diabetic dyslipidemia via synergistic action.As a representative tea variety of C.sinensis var.assamica,YK green tea was found to be superior to the other two green teas in preventing and treating diabetic dyslipidemia,especially with long term consumption.These data provide important information for tea plant breeders and tea consumers.
文摘On the stone-paved lanes of Songyang County that date back to ancient times,morning mist lingered as a faint fragrance of tea wafted from a century-old house.Inside,Yang Junjie,a tea maker born in the 1980s,worked deftly at the stove,his hands moving swiftly over the scorching iron wok as tender green tea leaves dance between his fingers.
文摘Blending tradition with modern elements,Songyang’s tea industry attracts young entrepreneurs to revive culture and drive economic growth.SONGYANG has a long and rich history of tea cultivation and production.The county became famous for its tea as early as the Three Kingdoms period(220-280).Today,this land is home to over 10,000 hectares of ecofriendly tea plantations.One in every three Songyang residents is involved in the tea industry,whose full industrial chain value now exceeds RMB 13.5 billion.
文摘Paying an additional RMB 2 could have your next milk tea delivered by drone to your balcony in just five minutes.This small fee represents the vast potential of the trillion-yuan lowaltitude economy.
基金supported by Project of Zhangjiajie City’s Industry-Academia-Research Collaborative Innovation‘Open Project Leader’,Zhangjiajie City’s Project of Taking on Challenging Tasks by Responding to Calls for Solutions(JB20230530)Basic Research Funds Project for Central Universities of China(2023XCZX001,2020kfyXJJS120)Academician and Expert Workstations in Yunnan Province(202205AF150090).
文摘Vine tea is documented in ancient Chinese books as having the function of promoting blood circulation.However,its effects and mechanisms remain unclear.The aim of this study was to comprehensively investigate the protective potential and mechanisms of vine tea in high-fat diet rat through a combination of in vivo and in vitro experiments.The efficacy of vine tea was evaluated using a high-fat diet rat model and an oxidized low-density lipoprotein-treated cell model,with physiological and biochemical indicators measured in rat serum and cell supernatants.Transcriptomics was utilized to investigate alterations mRNA expression following the administration of dihydromyricetin in cell model.Metabolomics and 16S rRNA sequencing was employed to examine changes in metabolites in the serum and changes in gut microbiota of high-fat diet rats after administering vine tea extract.Vine tea extract and dihydromyricetin can reduce elevated levels of lipids,including total cholesterol and triglycerides,following modeling.Transcriptomic data indicate that dihydromyricetin exerts its effects by regulating ferroptosis signaling pathways.Metabolomic analysis demonstrates that the administration of vine tea extract influences the vitamin K cycle and glutathione,thereby alleviating the progression of ferroptosis.Additionally,16S rRNA sequencing reveals that vine tea extract increases Lactobacillaceae in the gut microbiota,which subsequently affects the levels of lysophosphatidylcholine,a major phospholipid component of oxidized low-density lipoprotein in serum.Our results indicate that vine tea can regulate ferroptosis signaling pathways and increase Lactobacillaceae in the gut microbiota,thereby exhibiting cardiovascular protective effects in high-fat diet rats.
基金supported by the National Key Research and Development Program of China(2022YFD2101101)the Earmarked Fund for CARS-19+2 种基金the National Natural Science Foundation of China(32402634)the Modern Agricultural(Tea)Industry Technology System of Fujian Province,China(2025 No.593)the Special Fund for Science and Technology Innovation of Fujian Zhang Tianfu Tea Development Foundation,China(FJZTF01)。
文摘Understanding the molecular responses of tea leaves to mechanical stress is crucial for elucidating the mechanisms of post-harvest quality formation during oolong tea processing.This study employed an integrated multi-omics strategy to characterize the changes and interactions among metabolomic(MB),transcriptomic(TX),and proteomic(PT)profiles in mechanically stressed tea leaves.Mechanical stress initially activated damage-associated molecular patterns(DAMPs),including Ca^(2+)signaling,jasmonic acid signaling,and glutathione metabolism pathways.These processes subsequently induced quality-related metabolic pathways(QRMPs),particularly α-linolenic acid and phenylalanine metabolism.Upregulated expression of LOX,ADH1,and PAR genes,together with the increased abundance of their encoded proteins,respectively promoted the accumulation of jasmine lactone,benzyl alcohol,and 2-phenylethanol.These findings indicate that mechanical stress influences the metabolite biosynthesis in tea leaves through coordinated molecular responses.This study provides new insights into the molecular mechanisms underlying tea leaf responses to mechanical stress and a foundation for future investigations into how early molecular events may contribute to post-harvest metabolic changes during oolong tea processing.
基金supported by the National Natural Science Foundation of China(Grant Nos.32072630,32372774,and U22A20499)the earmarked fund for CARS(Grant No.CARS-19-01A).
文摘Tea plant(Camellia sinensis(L.)O.Kuntze)is a cold-sensitive leaf-harvesting crop whose growth,yield,and processed tea quality are all inhibited by low temperatures.Therefore,identifying the regulatory genes involved in tea plant growth and freezing tolerance is crucial for genetic improvement.WRKY transcription factors regulate various plant processes,including growth and development,stress responses,and metabolite biosynthesis.However,the molecular network through which WRKY coordinates these pathways in tea plants remains unclear.In this study,we revealed that CsWRKY57L,a cold-inducible WRKY IIc subfamily member,positively regulated freezing tolerance by directly promoting flavonoid accumulation in tea plants.Transient suppression of CsWRKY57L weakened the freezing tolerance of tea plants by reducing flavonoid content and suppressing the C-repeat-binding factor(CBF)-cold-responsive(COR)gene pathway.In contrast,heterologous overexpression of CsWRKY57L in Arabidopsis had the opposite effect.Additionally,overexpression of CsWRKY57L inhibited reproductive development and accelerated senescence in Arabidopsis.Interaction analysis revealed that CsWRKY57L directly binds to the promoters of CsSWEET1a,CsSWEET15,and AtSWEET15,which encode sugar transporters essential for plant reproductive development,and inhibits their transcription.Overall,the study revealed a dual role of CsWRKY57L in promoting freezing tolerance via flavonoid biosynthesis and inhibiting reproductive development by regulating SWEETs expression.This study uncovers a novel mechanism whereby CsWRKY57L coordinately regulates both stress responses and growth in tea plants,providing a molecular basis for breeding low-temperature-tolerant varieties with restricted reproductive development.
基金funded by the Global PhD Scholarship between KU Leuven and UCLouvain。
文摘Litter decomposition is an essential ecosystem process influenced by multiple factors,including substrate quality,climate,edaphic environment,and decomposer communities.However,the role of canopy species identity and diversity on leaf litter decomposition in forests remains understudied.By controlling for macroclimate,soil properties,and litter substrate in a mature common garden,we investigated whether a three-month tea bag incubation of standardized green and rooibos tea substrate is driven by canopy tree species characteristics and diversity.Our study hypothesized two primary pathways:a chemical engineering effect,where trees alter soil properties and decomposer communities through litter input,and a physical engineering effect,where tree canopy structure modulates the local microclimate.The results showed that even under uniform macroclimatic and initial soil conditions,mass loss rates varied widely for green tea(27.4%–73.2%)and rooibos tea(6.1%–34.7%),comparable as found in other research between distinct biomes.While substrate quality was the dominant factor,both engineering pathways and,to a minor extent,tree diversity modulated mass losses.For green tea,tree chemical and physical characteristics seemed equally important,while the physical environment showed an increased importance for rooibos.Incubation depth played a key role,where forest floor decomposition rates are more susceptible to temporal climate variations,and soil-layer decomposition rates are less susceptible to climate variations and more determined by tree species identity.Our findings suggest that tea bag experiments focusing solely on topsoil burial may underestimate processes in the forest floor and the mineralorganic boundary layer.This study underscores the critical role of litter substrate quality in decomposition while demonstrating that tree community composition and the associated herbaceous layer,through both chemical and physical engineering pathways,strongly modulate decomposition rates.
基金the financial support from China Postdoctoral Science Foundation(2018M643205)
文摘Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) was developed to simultaneously determine 11 amino acids in different types of tea (green teas, Oolong tea, black tea and Pu-erh tea). The separation conditions for the analysis of the selected amino acids including the column type, temperature and backpressure as well as the type of additive, were carefully optimized. The best separation of the 11 amino acids was obtained by adding water (5%, v/v) and trifluoroacetic acid (0.4%, v/v) to the organic modifier (methanol). Finally, the developed SFC-MS method was fully validated and successfully applied to the determination of these amino acids in six different tea samples. Good linearity (r ≥ 0.993), precision (RSDs≤ 2.99%), accuracy (91.95%-107.09%) as well as good sample stability were observed. The limits of detection ranged from 1.42 to 14.69 ng/mL, while the limits of quantification were between 4.53 and 47.0 ng/mL. The results indicate that the contents of the 11 amino acids in the six different tea samples are greatly influenced by the degree of fermentation. The proposed SFC-MS method shows a great potential for further investigation of tea varieties.
基金Project supported by the National Key Technologies R&D Program of China during the 11th Five-Year Plan Period (No. 2006BAK02A18)the Innovation Team of the Safety Standards and Testing Technology for Agricultural Products of Zhejiang Province,China(No. 2010R50028)
文摘The objective of this study was to investigate the geographical origin of Chinese teas using carbon and nitrogen stable isotope ratio technology.The results showed that inter-provincial dispersion of teas in Guangdong(GD),Guangxi(GX),Hainan(HA),Fujian(FJ),Shandong(SD),Sichuan(SC),Chongqing(CQ),and Henan(HN) provinces was high,while in Zhejiang(ZJ),Hubei(HB),Yunnan(YN),and Anhui(AH) provinces,it was low.Tea samples from GD,GX,HA,and FJ provinces were clustered in one group and separated from those from AH and HB provinces.Thus,carbon and nitrogen stable isotope ratio technology could discriminate teas from among some provinces of China,but not from among others.Better separation might be obtained with a combination of isotopic ratios and other indexes,such as elemental data and organic components.
基金supported by the Department of Education of Guangdong Province entitled innovation project “An Interpersonal Pragmatic Study of Humor in Chinese Broadcasting Context” (No.: 2017WQNCX042)Center for Linguistics and Applied Linguistics at Guandong Univerisity of Foreign Studies, China for the project of the frontier research and its theoretical innovation in interpersonal pragmatics (2018WZDXM006)+2 种基金China Scholarship Council (2018)participated in the Hungarian Academy funded MTA Lendulet (LP2017/5) project of Professor Dániel Z.Kádárthe support from the Chinese MOE Research Project of Humanities and Social Science (Project No.: 16JJD740006) conducted by Center for Linguistics and Applied Linguistics, Guangdong University of Foreign Studies.
文摘Teasing can be approached as a linguistic resource for examining the interpersonal issues of im/politeness and face,or as a discursive strategy for displaying relationships or constructing social identities.However,studies have underestimated the discursive constraints of teasing in specific contexts.Meanwhile,a majority of teasing studies were based on Western cultures and did not pay sufficient attention to the variety of teasing across cultures.By collecting data from two Chinese entertainment interviews,where the interviewer employs teasing frequently for performing institutional roles,this study examined how teasing functions to assist the interviewer to complete communicative goals,and explored the discursive constraints of teasing in media context.Data analysis exemplified how teasing helped the interviewer to manage an interview event,obtain the vip’s disclosure and seek audience involvement,helping to construct the interviewer’s professionality.Implications for understanding the discursive features of teasing in the Chinese media context were addressed.
