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In-situ deposited anti-aging TiN capping layer for Nb superconducting quantum circuits
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作者 Hao-Ran Tao Lei Du +8 位作者 Liang-Liang Guo Yong Chen Hai-Feng Zhang Xiao-Yan Yang Guo-Liang Xu Chi Zhang Zhi-Long Jia Peng Duan Guo-Ping Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期133-137,共5页
The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal–air interface,where Nb2O5 is considered the main loss source.Here,we suppress the formation of native oxi... The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal–air interface,where Nb2O5 is considered the main loss source.Here,we suppress the formation of native oxides by in-situ deposition of a TiN capping layer on the Nb film.With TiN capping layers,no Nb2O5 forms on the surface of the Nb film.The quality factor Qi of the Nb resonator increases from 5.6×10^(5) to 7.9×10^(5) at low input power and from 6.8×10^(6) to 1.1×10^(7)at high input power.Furthermore,the TiN capping layer also shows good aging resistance in Nb resonator devices,with no significant performance fluctuations after one month of aging.These findings highlight the effectiveness of TiN capping layers in enhancing the performance and longevity of Nb superconducting quantum devices. 展开更多
关键词 anti-aging oxidation dielectric loss Nb superconducting quantum circuits
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Anti-aging performance improvement and enhanced combustion efficiency of boron via the coating of PDA
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作者 Shuai Ma Qinghai Shu +4 位作者 Mengyang Zhang Hongyu Huang Yansong Shi Xijuan Lv Shuai Zhao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期399-410,共12页
Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during storage.The polydopamine(PDA)was introduced in... Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during storage.The polydopamine(PDA)was introduced into boron particles,investigating the impact of PDA content on the energetic behavior of boron.The results indicated that the PDA coating formed a fishing net structure on the surface of boron particles.The heat release results showed that the combustion calorific value of B@PDA was higher than that of the raw boron.Specifically,the actual combustion heat of boron powder in B@10%PDA increased by 38.08%.Meanwhile,the DSC peak temperature decreased by 100.65℃under similar oxidation rate compared to raw boron.Simultaneously,the B@PDA@AP and B@AP composites were prepared,and their combustion properties were evaluated.It was demonstrated that B@10%PDA@AP exhibited superior performance in terms of peak pressure and burning time,respectively.The peak pressure is 12.43 kPa more than B@AP and burning time is 2.22 times higher than B@AP.Therefore,the coating of PDA effectively inhibits the oxidization of boron during storage and enhances the energetic behavior of boron and corresponding composites. 展开更多
关键词 Boron particles POLYDOPAMINE anti-aging performance improvement Heat release
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Correlation of gut microorganisms and non-volatile flavor substances provides new insights for breeding Scylla paramamosain
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作者 Gao GAO Xing LI +7 位作者 Kangxiang QIN Yun HU Xiaosong JIANG Chenxi CHE Yuntao LI Changkao MU Chunlin WANG Huan WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1336-1347,共12页
The farming of Scylla paramamosain with specific flavors has a higher commercial value,and the flavors are related to the integrated farming environment and non-volatile flavor substances,while the survival environmen... The farming of Scylla paramamosain with specific flavors has a higher commercial value,and the flavors are related to the integrated farming environment and non-volatile flavor substances,while the survival environment is one of the important ways to source gut microorganisms in the organism.In this study,the levels of dominant taxa in the gut flora of S.paramamosain from Mong Cai,Vietnam(VN),Taishan City,Guangdong Province(TS)of China,and Ninghai County,Ningbo City(NB)Zhejiang Province of China converged with those of S.paramamosain from Sanmen County,Ningbo City(CK 1,CK 2,and CK 3)at 28 d of domestication.The top 15 genera with the highest abundance of VN,TS,and NB gut flora were the same as CK 1,CK 2,and CK 3,but with different percentages,and gradually converged to CK 1,CK 2,and CK 3,respectively,at 28 d of domestication.Correlation between intestinal flora and non-volatile flavor substances in the hepatopancreas at the percentage level of relative abundance of bacterial genera found that above 28 d of domestication,Muribaculaceae,Psychrilyobacter,Clostridia_vadinBB 60_group,Halarcobacter Carboxylicivirga,Sediminispirochaeta may be the most important genera affecting flavor amino acids of VN.Sediminispirochaeta,Carboxylicivirga,Halarcobacter,Photobacterium,ZOR 0006,Psychrilyobacter,and Pseudomonas may be the most important genera affecting flavor amino acids of NB.Sediminispirochaeta,Carboxylicivirga,Halarcobacter,Photobacterium,ZOR 0006,Vibrio,and Sphingomonas may be the most important genera affecting flavor amino acids of TS.These results show that the intestinal flora structure of crabs from different areas were domesticated in the same area for at least 28 d before they converged to that of the domesticated crab,and the most important genera affecting the flavor amino acids of TS,VN,and NB were also identified.The results of this study provide a reference and basis for the technique of directional cultivation of the flavor quality of the crab. 展开更多
关键词 survival environment Scylla paramamosain intestinal flora structure non-volatile flavor substance directional breeding
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Occurrence,Spatial Distribution,Sources and Risk Assessment of Per-and Polyfluoroalkyl Substances in Surface Sediments of the Yellow River Delta Wetland
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作者 SUN Yu SHEN Nan +5 位作者 ZHANG Dahai CHEN Junhui HE Xiuping JI Yinli WANG Haiyang LI Xianguo 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第5期1263-1274,共12页
Per-and polyfluoroalkyl substances(PFASs)are emerging persistent organic pollutants(POPs).In this study,47 surface sediment samples were collected from the Yellow River Delta wetland(YRDW)to investigate the occurrence... Per-and polyfluoroalkyl substances(PFASs)are emerging persistent organic pollutants(POPs).In this study,47 surface sediment samples were collected from the Yellow River Delta wetland(YRDW)to investigate the occurrence,spatial distribution,potential sources,and ecological risks of PFASs.Twenty-three out of 26 targeted PFASs were detected in surface sediment samples from the YRDW,with totalΣ23PFASs concentrations ranging from 0.23 to 16.30 ng g^(-1) dw and a median value of 2.27 ng g^(-1) dw.Perfluorooctanoic acid(PFOA),perfluorobutanoic acid(PFBA)and perfluorooctanesulfonic acid(PFOS)were the main contaminants.The detection frequency and concentration of perfluoroalkyl carboxylic acids(PFCAs)were higher than those of perfluoroal-kanesulfonic acids(PFSAs),while those of long-chain PFASs were higher than those of short-chain PFASs.The emerging PFASs substitutes were dominated by 6:2 chlorinated polyfluoroalkyl ether sulfonic acid(6:2 Cl-PFESA).The distribution of PFASs is significantly influenced by the total organic carbon content in the sediments.The concentration of PFASs seems to be related to human activities,with high concentration levels of PFASs near locations such as beaches and villages.By using a positive matrix factorization model,the potential sources of PFASs in the region were identified as metal plating mist inhibitor and fluoropolymer manufacturing sources,metal plating industry and firefighting foam and textile treatment sources,and food packaging material sources.The risk assessment indicated that PFASs in YRDW sediments do not pose a significant ecological risk to benthic organisms in the region overall,but PFOA and PFOS exert a low to moderate risk at individual stations. 展开更多
关键词 per-and polyfluoroalkyl substances Yellow River Delta wetland sediment source identification risk assessment
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Research Progress of Volatile Substances Analysis and Sensory Evaluation of Soymilk
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作者 Xu Qiongyuan Li Ka +7 位作者 Huang Meina Liang Yuxin Tao Bingjie Zhang Tingting Song Nannan Ji Yazhou Zhang Huajiang Xia Ning 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期74-82,共9页
Soybean is one of the important crops in China. Soymilk, a traditional neutral plant-based protein drink, is rich in high quality proteins. Although soybean milk is rich in nutrients, its marketing among consumers, es... Soybean is one of the important crops in China. Soymilk, a traditional neutral plant-based protein drink, is rich in high quality proteins. Although soybean milk is rich in nutrients, its marketing among consumers, especially those in Western countries who are used to peaceful flavor, has been limited due to the adverse flavor impact brought by its special composition. In recent years, with the increasing attention to the nutritional value of soymilk, the flavor of soymilk has become a popular research object for scholars at home and abroad. The flavor components of soymilk are mainly volatile small molecular compounds produced by enzymatic reactions catalyzed by lipoxygenase(LOX). After formation, they interact with protein macromolecules to form the overall flavor of soymilk. At present, there are many methods to control the off-odor of soymilk at home and abroad, including physical heating methods, chemical methods, biological enzymatic digestion methods, mask methods, and a variety of breeding methods. These methods effectively reduce the off-odor of soymilk, but all of them have shortcomings. Currently, the sensory characteristics of the beany odor in soymilk are evaluated mainly by traditional human sensory scoring along with the assistance of modern instrument analysis of volatile flavor substances using headspace solid phase microextraction(SPME) gas chromatography coupled with-mass spectrometry(GC-MS). This paper summarized the research results of volatile flavor substances in soymilk in recent years and the sensory evaluation methods of soymilk at home and abroad, and looked forward to the future development direction, hoping to provide some theoretical bases and reference detection methods for solving the problem of soymilk flavor in the future. 展开更多
关键词 SOYMILK off-odor volatile substance FLAVOR sensory evaluation
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Evaluation of Rhizobium tropici-Derived Extracellular Polymeric Substances on Selected Soil Properties, Seed Germination, and Growth of Black-Eyed Peas (Vigna unguiculata)
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作者 Jonathan Alunge Metuge Erneste Havugimana +2 位作者 Jean Rugandirababisha Zachary N. Senwo Marie Chantal Mutimawurugo 《Agricultural Sciences》 2024年第5期548-564,共17页
Rhizobium tropici-derived extracellular polymeric substances (EPS) have been used in soils to enhance soil structures and mitigate soil erosions. However, information on their use to improve soil health and fertility ... Rhizobium tropici-derived extracellular polymeric substances (EPS) have been used in soils to enhance soil structures and mitigate soil erosions. However, information on their use to improve soil health and fertility indicators, and plant growth is limited. In a greenhouse study, we investigated their effects on some soil health, soil fertility indices, and the growth of black-eyed peas (Vigna unguiculate). Results showed that soils incubated with EPS significantly increased basal soil respiration, soil microbial biomass, permanganate oxidizable carbon (POC), and potentially mineralizable nitrogen (PMN). The EPS shifted microbial populations from bacteria to fungi and Gram (−ve) to Gram ( ve) bacteria. However, it had little or no effects on soil pH, soil organic matter (SOM), and cation exchange capacity (CEC). The EPS decreased soil moisture loss, increased soil aggregate stability, but delayed blacked-eyed peas germinations in the soils. At 0.1% (w/w) concentrations in soils, there was increase in plant root nodulations and vegetative growth. This study was carried out within 40 days of incubating soils with EPS or growing the black-eyed peas in a greenhouse study. The plant growth parameters were taken before flowering and fruiting. Further studies of the effects of incubating soils with the extracellular polymeric substances on plant growth. Soil microbial biomass, microbial diversities, and other soil fertility indices are deemed necessary. 展开更多
关键词 Rhizobium tropici Extracellular Polymeric substances Soil Respiration Soil Microbial Biomass Black-Eyed Peas
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Contemporary strategies and approaches for characterizing composition and enhancing biofilm penetration targeting bacterial extracellular polymeric substances
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作者 Lan Lu Yuting Zhao +4 位作者 Mingxing Li Xiaobo Wang Jie Zhu Li Liao Jingya Wang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期506-524,共19页
Extracellular polymeric substances(EPS)constitutes crucial elements within bacterial biofilms,facili-tating accelerated antimicrobial resistance and conferring defense against the host's immune cells.Developing pr... Extracellular polymeric substances(EPS)constitutes crucial elements within bacterial biofilms,facili-tating accelerated antimicrobial resistance and conferring defense against the host's immune cells.Developing precise and effective antibiofilm approaches and strategies,tailored to the specific charac-teristics of EPS composition,can offer valuable insights for the creation of novel antimicrobial drugs.This,in turn,holds the potential to mitigate the alarming issue of bacterial drug resistance.Current analysis of EPS compositions relies heavily on colorimetric approaches with a significant bias,which is likely due to the selection of a standard compound and the cross-interference of various EPS compounds.Considering the pivotal role of EPS in biofilm functionality,it is imperative for EPS research to delve deeper into the analysis of intricate compositions,moving beyond the current focus on polymeric materials.This ne-cessitates a shift from heavy reliance on colorimetric analytic methods to more comprehensive and nuanced analytical approaches.In this study,we have provided a comprehensive summary of existing analytical methods utilized in the characterization of EPS compositions.Additionally,novel strategies aimed at targeting EPS to enhance biofilm penetration were explored,with a specific focus on high-lighting the limitations associated with colorimetric methods.Furthermore,we have outlined the challenges faced in identifying additional components of EPS and propose a prospective research plan to address these challenges.This review has the potential to guide future researchers in the search for novel compounds capable of suppressing EPS,thereby inhibiting biofilm formation.This insight opens up a new avenue for exploration within this research domain. 展开更多
关键词 Analytic strategies and approaches Composition characterization Extracellular polymeric substances(EPS) Promoting biofilm penetration
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Fuzzy Multi-Criteria Decision Support System for the Best Anti-Aging Treatment Selection Process through Normal Wiggly Hesitant Fuzzy Sets
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作者 Daekook Kang Ramya Lakshmanaraj +5 位作者 Samayan Narayanamoorthy Navaneethakrishnan Suganthi Keerthana Devi Samayan Kalaiselvan Ranganathan Saraswathy Dragan Pamucar Vladimir Simic 《Computers, Materials & Continua》 SCIE EI 2024年第9期4947-4972,共26页
This socialized environment among educated and developed people causes themto focusmore on their appearance and health,which turns them towards medical-related treatments,leading us to discuss anti-aging treatment met... This socialized environment among educated and developed people causes themto focusmore on their appearance and health,which turns them towards medical-related treatments,leading us to discuss anti-aging treatment methods for each age group,particularly for urban people who are interested in this.Some anti-aging therapies are used to address the alterations brought on by aging in human life without the need for surgery or negative effects.Five anti-aging therapies such as microdermabrasion or dermabrasion,laser resurfacing anti-aging skin treatments,chemical peels,dermal fillers for aged skin,and botox injections are considered in this study.Based on the criteria of safety risk,investment cost,customer happiness,and side effects,the optimal alternative is picked.As a result,a NormalWiggly Hesitant Pythagorean Fuzzy Set(NWHPFS)is constructed and used in Multi-Criteria Decision-Making(MCDM)using traditional wavy mathematical approaches.The entropy approach is utilized to determine weight values,and the Normal Wiggly Hesitant Pythagorean-VlseKriterijumska Optimizacija I Kompromisno Resenje(NWHPF-VIKOR)method is utilized to rank alternatives using MCDM methodologies.Sensitivity analysis and comparative analysis were performed to ensure the robustness and reliability of the proposed method.The smart final choice will undoubtedly assist Decision Makers(DM)in making the right judgments,and the MCDM approach will undoubtedly assist individuals in understanding the medicine. 展开更多
关键词 Normal wiggly hesitant pythagorean fuzzy set hesitant pythagorean fuzzy set anti-aging treatment entropy VIse Kriterijumska Optimizacija I Kompromisno Resenje
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Anti-aging based on stem cell therapy:A scoping review
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作者 Nassar El Assaad Alain Chebly +8 位作者 Rawad Salame Robert Achkar Nour Bou Atme Khalil Akouch Paul Rafoul Colette Hanna Samer Abou Zeid Marwan Ghosn Charbel Khalil 《World Journal of Experimental Medicine》 2024年第3期57-63,共7页
Stem cells are present in the tissues and organs and remain in a quiescent and undifferentiated state until it is physiologically necessary to produce new descendant cells.Due to their multipotency property,mesenchyma... Stem cells are present in the tissues and organs and remain in a quiescent and undifferentiated state until it is physiologically necessary to produce new descendant cells.Due to their multipotency property,mesenchymal stem cells have attracted considerable attention worldwide due to their immunomodulation and therapeutic function in tissue regeneration.Stem cells secrete components such as paracrine factors,extracellular vesicles,and exosomes which have been shown to have anti-inflammatory,anti-aging,reconstruction and wound healing potentials in many in vitro and in vivo models.The pluripotency and immunomodulatory features of stem cells could potentially be an effective tool in cell therapy and tissue repair.Aging affects the capacity for self-renewal and differentiation of stem cells,decreasing the potential for regeneration and the loss of optimal functions in organisms over time.Current progress in the field of cellular therapy and regenerative medicine has facilitated the evolution of particular guidelines and quality control approaches,which eventually lead to clinical trials.Cell therapy could potentially be one of the most promising therapies to control aging due to the fact that single stem cell transplantation can regenerate or substitute the injured tissue.To understand the involvement of stem cells not only in tissue maintenance and disease but also in the control of aging it is important to know and identify their properties,functions,and regulation in vivo,which are addressed in this review. 展开更多
关键词 Mesenchymal stem cell anti-aging TELOMERASE Regenerative medicine Stem cell therapy
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Preserving the Ozone Layers: Battling Illegal Trade in Ozone-Depleting Substances
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作者 Ibrahim Badawi 《Atmospheric and Climate Sciences》 2024年第3期287-298,共12页
The depletion of the ozone layer, a vital shield protecting the Earth from harmful ultraviolet (UV) radiation, is now a worldwide environmental concern. Human activities, particularly the release of ozone depleting su... The depletion of the ozone layer, a vital shield protecting the Earth from harmful ultraviolet (UV) radiation, is now a worldwide environmental concern. Human activities, particularly the release of ozone depleting substances (ODS), have led to the thinning of this protective layer over recent decades. Simultaneously, illegal trade has emerged as a global challenge, giving rise to economic issues, losses of tax revenue, heightened criminal activities, health risks, and environmental hazards. The depletion of the ozone layer, a critical shield protecting the Earth from harmful ultraviolet (UV) radiation, has become a global environmental concern. This paper delves into the legal dimensions surrounding ozone-depleting substances (ODS), their impact on the ozone layer, and the subsequent risk of skin cancer. As countries navigate international agreements, domestic regulations, and enforcement mechanisms, the intricate interplay between legal frameworks and the health implications of ozone layer depletion comes to the forefront. The paper highlights particular instances of illegal trade in ozone depleting substances, drawing from data reported by the parties to the Montreal Protocol. Notably, China stands out as a significant source of contraband ODS, with other countries such as Bulgaria, Lithuania, Poland, and France reporting numerous cases. Analyzing these case instances offers insights into the efficacy of legal frameworks and enforcement measures. The paper offers a comprehensive set of recommendations to strengthen global control and enforcement against the illegal trade of ozone depleting substances. These recommendations span diverse aspects such as production monitoring, customs collaboration, mutual verification, cross-border agreements, public-private partnerships, international cooperation, detection equipment, global regulatory standards, resource allocation, public awareness campaigns, alternative substance development, and controlling the trade at its source. By applying these recommendations and enhancing enforcement measures, we aim to protect the ozone layer and create a healthier and safer world for future generations and achieve sustainable development goals. 展开更多
关键词 Ozone-Depleting substances Illegal Trade Montreal Protocol Environmental Protection Ozone Layers Climate Change
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Application of plant extracts cosmetics in the field of anti-aging
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作者 Minghui Xie Zibing Jiang +1 位作者 Xingyue Lin Xingchuan Wei 《Journal of Dermatologic Science and Cosmetic Technology》 2024年第2期53-62,共10页
Skin aging is a direct manifestation of body aging,representing a complex and irreversible natural process,which is influenced by genetics,lifestyle and environmental factors.In the process of skin aging,the skin epid... Skin aging is a direct manifestation of body aging,representing a complex and irreversible natural process,which is influenced by genetics,lifestyle and environmental factors.In the process of skin aging,the skin epidermis gradually become thinner,the inherent repair ability gradually weakens,the collagen and elastin gradually decrease and the skin gradually loses elasticity.Although skin aging is inevitable,it can be delayed to some extent by using cosmetics.Natural extract cosmetics are highly favored by consumers for their safety and efficacy,aligning with consumer preferences for natural,organic,efficient and sustainable skincare concepts.Numerous plant resources in nature possess superior properties like moisturizing,barrier repair,anti-oxidation,sunscreen whitening and anti-inflammatory properties after thousands of years of natural selection.These properties enable plant components to effectively enhance the anti-aging effects of skincare products through multiple anti-aging pathways,which can be widely used to develop natural anti-aging skin care products. 展开更多
关键词 Plant resources anti-aging Green Efficacy skin care COSMETICS
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The Role of Jasmonates as Antibulbing Substances in the Bulb Formation of Onion
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作者 Noboru Takada Atsushi Saito +4 位作者 Yuuki Matsuzuka Tatsushi Mochiduki Eriko Wakita Meng WANG Yasunori Koda 《Agricultural Biotechnology》 2024年第1期1-4,8,共5页
Onion plants form spherical bulbs under long-day conditions.Substances regulating bulb formation remain unknown.In the course of chemical studies on the bulb formation,α-linolenic acid was isolated from onion extract... Onion plants form spherical bulbs under long-day conditions.Substances regulating bulb formation remain unknown.In the course of chemical studies on the bulb formation,α-linolenic acid was isolated from onion extracts as an antibulbing substance,the amount of which was synchronized with the bulb formation.Since allene oxide synthase inhibitor canceled the antibulbing activity ofα-linolenic acid,it was disclosed that jasmonic acid concerns this regulation.Structure-activity-relationship study revealed that its(3R,7S)stereochemistry is necessary for showing its antibulbing activity.It is concluded that(3R,7S)-jasmonate derived fromα-linolenic acid actually participates in the regulation of bulb formation. 展开更多
关键词 Onion(Allim cepa L.cv.Higuma) ISOLATION Bulb formation Antibulbing substance α-Linolenic acid Methyl jasmonate
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Analyzing the pharmacological substances and targets of Xuefu Zhuyu decoction in hypertensive vascular endothelial cells
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作者 Rui-Xue Chen Jing Li +3 位作者 Guo-Zhen Dong Sheng-Yan Qiao Xiao Hu Li-Guo Chen 《Clinical Research Communications》 2024年第1期3-10,共8页
Background:Xuefu Zhuyu decoction(XFZY)could significantly improve the function of hypertensive vascular endothelial cells,but the targets and mechanism are not clear.This study is to analyze the pharmacological substa... Background:Xuefu Zhuyu decoction(XFZY)could significantly improve the function of hypertensive vascular endothelial cells,but the targets and mechanism are not clear.This study is to analyze the pharmacological substances and targets of Xuefu Zhuyu decoction in hypertensive vascular endothelial cells.Methods:This study used Xuefu Zhuyu decoction to intervene human umbilical vein endothelial cells incubated by hypertensive patients’serum,then detected the function of vascular endothelial cells.The aqueous extract of XFZY was analyzed and validated by liquid chromatography-mass spectrometry technology;Finally,macromolecular docking technology was used to analyze the potential active substances and targets of XFZY in the prevention and treatment of hypertension.Results:Compared with the model group,the XFZY group showed a significant increase in NO expression(P<0.01)and a significant decrease in ET-1 expression(P<0.001);and the expression of BIP,P-JNK,CHOP,and BAX in XFZY group cells was significantly decreased(P<0.001),while the expression of JNK and BCL2 was significantly increased(P<0.001).19 main compounds were identified in XFZY and there were 3 pairs of molecular complexes with high affinity for markers of the endoplasmic reticulum stress,including BIP-Hesperidin complex,BIP-HSYA complex and JNK-Naringin complex.Conclusion:This study analyzed the potential pharmacodynamic substance and targets of Xuefu Zhuyu decoction in improving the function of hypertensive vascular endothelial cells,which could provide a scientific basis for the future molecular mechanism of XFZY in treating hypertension. 展开更多
关键词 Xuefu Zhuyu decoction HYPERTENSION vascular endothelial cells pharmacological substances and targets
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Advances in Research Methods of Pharmacodynamic Substances in Traditional Chinese Medicines and Their Application in the Teaching of Traditional Chinese Medicine Analysi
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作者 Jiangwei Tian 《Journal of Contemporary Educational Research》 2024年第5期97-102,共6页
With the continuous progress of science and technology,the research methods of pharmacodynamic substances in traditional Chinese medicine are developing,and the application of these methods in teaching is becoming mor... With the continuous progress of science and technology,the research methods of pharmacodynamic substances in traditional Chinese medicine are developing,and the application of these methods in teaching is becoming more and more extensive.By introducing these research methods into the classroom,teachers can help students to deeply understand the nature and mechanism of action of pharmacodynamic substances in traditional Chinese medicine,and improve their interest in and knowledge of traditional Chinese medicine.This paper introduces the definition of pharmacodynamic substances in traditional Chinese medicine,research methods,and their application in the teaching of traditional Chinese medicine analysis. 展开更多
关键词 Traditional Chinese medicine Pharmacodynamic substances Teaching of traditional Chinese medicine analysis Teaching application
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Relationship and effect of redox potential,jarosites and extracellular polymeric substances in bioleaching chalcopyrite by acidithiobacillus ferrooxidans 被引量:13
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作者 余润兰 钟代立 +3 位作者 苗雷 吴发登 邱冠周 顾国华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1634-1640,共7页
The changes of pH,redox potential,concentrations of soluble iron ions and Cu^2+ with the time of bioleaching chalcopyrite concentrates by acidithiobacillus ferrooxidans were investigated under the different condition... The changes of pH,redox potential,concentrations of soluble iron ions and Cu^2+ with the time of bioleaching chalcopyrite concentrates by acidithiobacillus ferrooxidans were investigated under the different conditions of initial total-iron amount as well as mole ratio of Fe(III) to Fe(II) in the solutions containing synthetic extracellular polymeric substances (EPS).When the solution potential is lower than 650 mV (vs SHE),the inhibition of jarosites to bioleaching chalcopyrite is not vital as EPS produced by bacteria can retard the contamination through flocculating jarosites even if concentration of Fe(III) ions is up to 20 g/L but increases with increasing the concentration of Fe(III) ions;jarosites formed by bio-oxidized Fe3+ ions are more easy to adhere to outside surface of EPS space on chalcopyrite;the EPS layer with jarosites acts as a weak diffusion barrier to further rapidly create a high redox potential of more than 650 mV by bio-oxidizing Fe^2+ ions inside and outside EPS space into Fe^3+ ions,resulting in a rapid deterioration of ion diffusion performance of the EPS layer to inhibit bioleaching chalcopyrite severely and irreversibly. 展开更多
关键词 extracellular polymeric substances CHALCOPYRITE BIOLEACHING jarosites redox potential
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Interaction mechanism of Cu^(2+),Fe^(3+) ions and extracellular polymeric substances during bioleaching chalcopyrite by Acidithiobacillus ferrooxidans ATCC2370 被引量:11
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作者 余润兰 刘晶 +5 位作者 陈安 钟代立 李乾 覃文庆 邱冠周 顾帼华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期231-236,共6页
The extracellular polymeric substances(EPS) of Acidithiobacillus ferrooxidans ATCC 23270,and iron and copper enclosed in EPS were extracted by ultrasonication and centrifugation methods to determine the interaction ... The extracellular polymeric substances(EPS) of Acidithiobacillus ferrooxidans ATCC 23270,and iron and copper enclosed in EPS were extracted by ultrasonication and centrifugation methods to determine the interaction mechanism of Cu2+,Fe3+ and EPS during bioleaching chalcopyrite.Generally,Cu2+ ions can stimulate bacteria to produce more EPS than Fe3+ ions.The mass ratio of Fe3+/Cu2+ enclosed in EPS decreased gradually from about 4:1 to about 2:1 when the concentration of Cu2+ ions increased from 0.01 to 0.04 mol/L.The amount of iron and copper bound together by EPS in ferrous-free 9K medium containing 1% chalcopyrite was about 2 times of that in 9K medium containing 0.04 mol/L Cu2+ ions.It was inferred that the EPS with jarosites on the surface of chalcopyrite gradually acted as a weak diffusion barrier for Cu2+,Fe3+ ions transference during bioleaching chalcopyrite. 展开更多
关键词 extracellular polymeric substances iron ions copper ions BIOLEACHING CHALCOPYRITE
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Study on the Effect of Osmosis-regulating Substances and Organic Appendices on Somatic Embryogenesis in Wheat 被引量:4
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作者 孙朝霞 侯思宇 王玉国 《Agricultural Science & Technology》 CAS 2008年第3期46-48,共3页
[Objective] The study aimed to reveal the effect of osmosis-regulating substances and organic appendices on somatic embryogenesis in wheat. [Method] The suitable concentration combination of appendices was optimized b... [Objective] The study aimed to reveal the effect of osmosis-regulating substances and organic appendices on somatic embryogenesis in wheat. [Method] The suitable concentration combination of appendices was optimized by adding different concentrations of osmosis-regulating substances including mannitol, sorbitol and organic appendices such as Gln, CH and LH, into the somatic embryogenesis in wheat. [Result] The mannitol or sorbitol lower than 40 g/L was helpful for improving somatic embryogenesis; there was no significant difference in the induction rate of somatic embryogenesis when 300-500 mg/L Gln、CH or LH was respectively added into the induced medium, while somatic embryogenesis could be enhanced dramatically in the presence of 500 mg/L Gln together with 300 mg/L CH. [Conclusion] Somatic embryogenesis could be improved to some extent by different concentrations of osmosis-regulating substances and organic appendices, which laid foundation for establishing a more perfect system of somatic embryogenesis in wheat. 展开更多
关键词 WHEAT SOMATIC EMBRYOGENESIS ORGANIC appendix Osmosis-regulating substance
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Effects of Drought Stress on Osmotic Regulation Substances of Five Catalpa bungei Clones 被引量:3
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作者 董蕾 李吉跃 +2 位作者 王军辉 谢堃 苏艳 《Agricultural Science & Technology》 CAS 2013年第9期1335-1343,共9页
[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to d... [Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to differentiate the degrees of drought stress based on changes in soil water content and leaf water potential and investigate variations in contents of osmotic regulation substances(free proline,soluble sugar and soluble protein) in leaves of five Catalpa bungei clones under different degrees of drought stresses. [Result] According to changes in soil water content and leaf water potential, the whole process of drought stress was divided into normal level(CK, with soil water content of 97.49% and leaf water potential of-0.54MPa), light drought(LD with soil water content of 59.96% and leaf water potential of-1.28 MPa), mediate drought(MD with soil water content of 34.19% and leaf water potential of-2.32 MPa) and severe drought(SD with soil water content of 14.52%and leaf water potential of-2.99 MPa). The soil water content and leaf water potential of five Catalpa bungei clones reached the highest correlation in exponential fitting, with an average R2of 0.989 3(P0.001). The free proline content in leaves of five Catalpa bungei clones increased rapidly with the increasing degree of drought stress(P 0.001). To be specific, free proline contents of Catalpa bungei clones015-1 and 7080 were 34.39 and 33.41 times of the normal level under severe drought conditions, which reached an extremely significant level(P0.001); the free proline content of Catalpa bungei clone 1-3 rapidly increased to(855.46±227.52) μg/g Fw under light drought conditions. The soluble protein content in leaves showed different variation trends. To be specific, the soluble protein content of Catalpa bungei clone 7080 was the lowest at various drought stages and reached(1.644 ±0.137)mg/g Fw under normal conditions; the soluble protein content of Catalpa bungei clone 1-3 was relatively high under normal conditions and was reduced rapidly under light drought conditions, showing different response patterns. [Conclusion] Osmotic regulation substances in leaves of five Catalpa bungei clones all have certain response to drought stress. Free proline is the most important osmotic regulation substance, followed by soluble protein, while soluble sugar makes no significant contribution. According to changes in content of osmotic regulation substances, Catalpa bungei clone 7080 has relatively high capacity and good drought resistance, while Catalpa bungei clone 1-3 has the rapidest response to drought stress. 展开更多
关键词 Drought stress Catalpa bungei clones Osmotic regulation substances
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Development and Validation of Liquid Chromatographic Method for the Determination of the Related Substances of Rifampicin 被引量:2
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作者 朱斌 胡昌勤 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第1期19-23,共5页
A number of HPLC methods have been approved for the determination of rifampicin, but no references involved the assay of related substances of rifampicin. In the present paper, a reversed-phase liquid chromatographic ... A number of HPLC methods have been approved for the determination of rifampicin, but no references involved the assay of related substances of rifampicin. In the present paper, a reversed-phase liquid chromatographic method for the determination of related substances of rifampicin is developed and validated. Rifampicin and its related substances, including rifamycin SV, rifampicin N-oxide and 3-formylrifamycin SV were separated using a Zorbax Eclipse C8, 250×4.6 mm(i.d), 5 μm column by isocratic elution at a flow rate of 1 mL·min -1. The detector was set at 254 nm. The mobile phase is a mixture of methanol-acetonitrile -0.075 mol·L -1 monopotassium phosphate -1.0 mol·L -1 citric acid (31:31:35:3, v/v). The method validation included accuracy, precision, linearity, sensitivity and stability. All results are shown to be acceptable. 展开更多
关键词 RIFAMPICIN Related substances HPLC
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Effect of Different Flue-curing Techniques on the Taste and Aroma Substances of Tobacco Leaves 被引量:2
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作者 崔国民 汪伯军 +3 位作者 罗以贵 许安定 陈益银 杨超 《Agricultural Science & Technology》 CAS 2014年第2期251-257,285,共8页
[Objective]This study aimed to optimize the conditions for curing tobacco leaf, so as to improve its flavor and quality. [Method] Leaves of Yuanyan 87 were col ected and cured by three different techniques (moderate-... [Objective]This study aimed to optimize the conditions for curing tobacco leaf, so as to improve its flavor and quality. [Method] Leaves of Yuanyan 87 were col ected and cured by three different techniques (moderate-intensity conditions throughout the curing course; high-intensity conditions at leaf yel owing and wilting stages, moderate-intensity conditions at leaf drying and vein drying stages; high-in-tensity conditions throughout the curing course), and then the contents of 48 aroma substances and taste indices of the finished tobacco leaves were measured. [Result] The contents of 28 aroma substances in the tobacco leaves cured under high-inten-sity conditions throughout the course were higher and the taste indices of these to-bacco leaves were better, compared with those flue-cured by the other two tech-niques. The contents of the other 20 aroma substances were not significantly af-fected by the curing techniques. The second best technique was high-intensity con-ditions at leaf yel owing and wilting stages and moderate-intensity conditions at leaf drying and vein drying stages. Curing tobacco leaves at moderate-intensity condi-tions throughout the course was the worst one. [Conclusion] Compared with the oth-er two methods, the contents of aroma substances and taste indices of the tobacco leaves cured under high-intensive conditions throughout the course were the best. 展开更多
关键词 Flue-cured tobacco leaf Curing technique Aromatic substances Tasteindices
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