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Quantitative Study of Multiple Components in Tetracera asiatica Based on High-Performance Liquid Chromatography
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作者 Fangfang DA Yufeng CHEN +4 位作者 Ziwan YUAN Ying LIU Yaoting MENG Kequn HE Yanmin XIE 《Asian Agricultural Research》 2025年第10期28-31,44,共5页
[Objectives]To establish an HPLC method for the quantitative determination of multiple phenolic acid components in Tetracera asiatica medicinal material,providing a basis for establishing its quality standards.[Method... [Objectives]To establish an HPLC method for the quantitative determination of multiple phenolic acid components in Tetracera asiatica medicinal material,providing a basis for establishing its quality standards.[Methods]An Inertsil ODS-C 18 column(250 mm×4.6 mm,5μm)was used.The mobile phase consisted of acetonitrile-0.2% phosphoric acid solution(10:90).The flow rate was 1.0 mL/min.The detection wavelength was 274 nm.The column temperature was 25℃.The injection volume was 10μL.The content of three components,gallic acid,protocatechuic acid,and protocatechualdehyde,was determined in 13 batches of T.asiatica.[Results]Gallic acid showed good linearity within the range of 0.020-6.400μg/mL,protocatechuic acid within 0.201-6.432μg/mL,and protocatechualdehyde within 0.202-6.464μg/mL(r>0.9990).The average recovery rates ranged from 98.61%to 101.17%,with RSD s between 1.21%and 2.69%.[Conclusions]The quantitative determination method established in this study is simple and feasible,and can provide a basis for the quality evaluation of T.asiatica. 展开更多
关键词 Tetracera asiatica HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC) components QUANTITATIVE determination
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The serum fascin-1 and tumor components containing this protein in patients with head and neck squamous cell carcinoma:A pilot study 被引量:1
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作者 Gelena V.Kakurina Elena E.Sereda +4 位作者 Marina N.Stakheeva Liubov Tashireva Olga V.Cheremisina Irina V.Kondakova Evgeny L.Choinzonov 《Journal of Biomedical Research》 2025年第5期534-537,I0046,I0047,共6页
Dear Editor,Local recurrence and cervical lymph node metastases are major causes of mortality in patients with head and neck squamous cell carcinoma(HNSCC).To date,none of the proposed strategies for predicting outcom... Dear Editor,Local recurrence and cervical lymph node metastases are major causes of mortality in patients with head and neck squamous cell carcinoma(HNSCC).To date,none of the proposed strategies for predicting outcomes in this disease have proven fully effective,and a comprehensive physical examination remains the primary method for early detection and monitoring of HNSCC. 展开更多
关键词 serum fascin cervical lymph node metastases tumor components comprehensive physical examination head neck squamous cell carcinoma hnscc head neck squamous cell carcinoma pilot study local recurrence
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Cultural influences on fidelity components in recovery colleges: a study across 28 countries and territories
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作者 Yasuhiro Kotera Amy Ronaldson +41 位作者 Simran Takhi Simon Felix Mariam Namasaba Simon Lawrence Vanessa Kellermann Agnieszka Kapka Daniel Hayes Danielle Dunnett Tesnime Jebara Michio Murakami Ioannis Bakolis Julie Repper Sara Meddings Vicky Stergiopoulos Lisa Brophy Clara De Ruysscher Lene Eplov Charlotte Toernes Dagmar Narusson Bernd Puschner Ramona Hiltensperger Yuki Miyamoto Stynke Castelein Trude Gøril Klevan Hannah Morland-Jones Edith Moore Samson Tse Michael Ryan Gianfranco Zuaboni Charlotte Hanlon Laura Asher Wouter Vanderplasschen Susana Ochoa Jonna Tolonen Ashleigh Charles Mario Andrade Daniel Elton Peter Bates Julie Cooper Jason Grant Claire Henderson Mike Slade 《General Psychiatry》 2025年第3期208-219,共12页
Background Recovery colleges (RCs) support personal recovery through education, skill development and social support for people with mental health problems, carers and staff. Guided by co-production and adult learning... Background Recovery colleges (RCs) support personal recovery through education, skill development and social support for people with mental health problems, carers and staff. Guided by co-production and adult learning principles, RCs represent a recent mental health innovation. Since the first RC opened in England in 2009, RCs have expanded to 28 countries and territories. However, most RC research has been conducted in Western countries with similar cultural characteristics, limiting understanding of how RCs can be culturally adapted. The 12-item Recovery Colleges Characterisation and Testing (RECOLLECT) Fidelity Measure (RFM) evaluates the operational fidelity of RCs based on 12 components, but cultural influences on these components remain underexplored.Aims To assess associations between Hofstede’s cultural dimensions and RFM items to identify cultural influences on fidelity components.Methods A cross-sectional survey of RC managers was conducted across all 221 RCs. Mixed-effects regression models examined associations between Hofstede’s country-level cultural dimensions and item-level RFM scores, adjusted for healthcare expenditure and income inequality. Four cultural dimensions, obtained from Hofstede, were analysed: individualism (prioritising personal needs), indulgence (enjoyment-oriented), uncertainty avoidance (preference for predictability) and long-term orientation (future-focused).Results The RFM was completed by 169 (76%) RC managers. Seven RFM items showed associations with cultural dimensions. Equality was linked to short-term orientation, while learning was associated with individualism and uncertainty avoidance. Both individualism and indulgence influenced co-production and community focus. Commitment to recovery was shaped by all four cultural dimensions, with the strongest associations seen for individualism and indulgence. Individualism enhanced explicit focus on strengths-based practice, while uncertainty avoidance influenced course distinctiveness.Conclusions This study demonstrates how culture shapes RC fidelity components, providing actionable insights for cultural adaptation. Incorporating under-represented dimensions, such as collectivism and restraint, could improve the RFM’s global applicability, facilitating implementation. Future research should explore cultural nuances, engage diverse stakeholders and refine fidelity measures to enhance RC inclusivity and effectiveness worldwide. 展开更多
关键词 social support co production fidelity components Hofstedes cultural dimensions skill development cultural influences recovery colleges personal recovery
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Comment on Virtanen et al.(2025) 'Digital components and interaction types in counseling interventions for childhood and adolescent obesity:A systematic review.'
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作者 Alina Yang 《International Journal of Nursing Sciences》 2025年第3期I0001-I0001,共1页
To the Editor:As a student actively involved in advocacy for heart disease prevention,I was particularly intrigued by the policymaking implications of digital interventions in the article "Digital components and ... To the Editor:As a student actively involved in advocacy for heart disease prevention,I was particularly intrigued by the policymaking implications of digital interventions in the article "Digital components and interaction types in counseling interventions for childhood and adolescent obesity:A systematic review" [1].Through my work as the Founder and President of the nonprofit Guardians of Heart,I have developed and promoted early educational programs,digital tools,and community outreach initiatives designed to instill heart-healthy habits in youth,intending to mitigate risk factors such as obesity that significantly contribute to cardiovascular disease later in life. 展开更多
关键词 digital components interaction types adolescent obesity community outreach initiatives heart disease policymaking implications childhood obesity systematic review digital interventions
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Effects of extrusion die cavity on the texture components and the associated mechanical properties for ZK60 magnesium alloy
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作者 Wenke Wang Wenzhuo Xie +7 位作者 Taotao Kang Xinhua Liu Li Hu Wenxue Zhang Hao Liu Wenzhen Chen Wencong Zhang Shijie Zhou 《Journal of Magnesium and Alloys》 2025年第9期4259-4277,共19页
This work managed the extrusion strain path by designing various extrusion die cavities,successfully realizing the texture modification for the ZK60 magnesium alloy.The mechanisms involving the texture dependence on t... This work managed the extrusion strain path by designing various extrusion die cavities,successfully realizing the texture modification for the ZK60 magnesium alloy.The mechanisms involving the texture dependence on the extrusion die cavity as well as their effects on the mechanical properties were emphatically investigated.Results showed that dynamic recrystallization refined the grain size and improved the microstructure homogeneity in the three extrusion specimens,but did not produce too large microstructure differences.By comparison,significant texture differences developed owing to the various extrusion die cavities,which here were mainly reflected in the strong or weak texture components for the c-axes//TD and the c-axes//ND.Such texture differences started from the deformation texture instead of the recrystallization texture whose roles only consisted in dispersing the texture component and reducing the texture intensity.The results from the finite element analysis and the visco-plastic self-consistent model indicated that,in order to accommodate the different strain components induced by the extrusion die cavities,slip systems or tension twinning were activated differently,and this was the critical reason causing the above texture differences.One modified Hall-Petch relationship was adopted to analyze the conjoint effects of grain refinement and texture variation on the yield stress.Additionally,the quantitative results about deformation mechanism activation fractions demonstrated that the texture variations influenced the competition relationships between the twinning induced deformation and the slip dominant deformation,and the former generally produced the lower yield stress and the increasing stage of strain hardening rate,while the latter produced the higher yield stress and the continuous decline of strain hardening rate. 展开更多
关键词 Extrusion die cavity Dynamic recrystallization TEXTURE Strain components Yield stress Strain hardening
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The Influence of LOS Components on the Statistical Properties of the Capacity of Amplify-and-Forward Channels
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作者 Gulzaib RAFIQ Matthias PATZOLD 《Wireless Sensor Network》 2009年第1期7-14,共8页
Amplify-and-forward channels in cooperative networks provide a promising improvement in the network coverage and system throughput. Under line-of-sight (LOS) propagation conditions in such cooperative networks, the ov... Amplify-and-forward channels in cooperative networks provide a promising improvement in the network coverage and system throughput. Under line-of-sight (LOS) propagation conditions in such cooperative networks, the overall fading channel can be modeled by a double Rice process. In this article, we have stud-ied the statistical properties of the capacity of double Rice fading channels. We have derived the analytical expressions for the probability density function (PDF), cumulative distribution function (CDF), level- crossing rate (LCR), and average duration of fades (ADF) of the channel capacity. The obtained results are studied for different values of the amplitudes of the LOS components in the two links of double Rice fading channels. It has been observed that the statistics of the capacity of double Rice fading channels are quite dif-ferent from those of double Rayleigh and classical Rice fading channels. Moreover, the presence of an LOS component in any of the two links increases the mean channel capacity and the LCR of the channel capacity. The validity of the theoretical results is confirmed by simulations. The results presented in this article can be very useful for communication system designers to optimize the performance of cooperative networks in wireless communication systems. 展开更多
关键词 AMPLIFY-AND-FORWARD CHANNELS Channel Capacity Cooperative Networks LINE-OF-SIGHT Component DOUBLE Rice PROCESS DOUBLE Rayleigh PROCESS Level-Crossing Rate Average Duration of Fades
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Research on multi-scale simulation and dynamic verification of high dynamic MEMS components in additive manufacturing 被引量:1
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作者 Sining Lv Hengzhen Feng +2 位作者 Wenzhong Lou Chuan Xiao Shiyi Li 《Defence Technology(防务技术)》 2025年第5期275-291,共17页
Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects s... Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects such as porosity issues, significant deformation, surface cracks, and challenging control of surface morphology encountered during the selective laser melting(SLM) additive manufacturing(AM) process of specialized Micro Electromechanical System(MEMS) components, multiparameter optimization and micro powder melt pool/macro-scale mechanical properties control simulation of specialized components are conducted. The optimal parameters obtained through highprecision preparation and machining of components and static/high dynamic verification are: laser power of 110 W, laser speed of 600 mm/s, laser diameter of 75 μm, and scanning spacing of 50 μm. The density of the subordinate components under this reference can reach 99.15%, the surface hardness can reach 51.9 HRA, the yield strength can reach 550 MPa, the maximum machining error of the components is 4.73%, and the average surface roughness is 0.45 μm. Through dynamic hammering and high dynamic firing verification, SLM components meet the requirements for overload resistance. The results have proven that MEM technology can provide a new means for the processing of MEMS components applied in high dynamic environments. The parameters obtained in the conclusion can provide a design basis for the additive preparation of MEMS components. 展开更多
关键词 Additive manufacturing High dynamic MEMS components Multiscale control Process optimization High dynamic verification
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Prediction of joint roughness coefficient via hybrid machine learning model combined with principal components analysis 被引量:1
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作者 Shijie Xie Hang Lin +2 位作者 Tianxing Ma Kang Peng Zhen Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2291-2306,共16页
Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC... Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC is a nonlinear system with a lot of overlapping information.In this paper,a dataset of eight roughness statistical parameters covering 112 digital joints is established.Then,the principal component analysis method is introduced to extract the significant information,which solves the information overlap problem of roughness characterization.Based on the two principal components of extracted features,the white shark optimizer algorithm was introduced to optimize the extreme gradient boosting model,and a new machine learning(ML)prediction model was established.The prediction accuracy of the new model and the other 17 models was measured using statistical metrics.The results show that the prediction result of the new model is more consistent with the real JRC value,with higher recognition accuracy and generalization ability. 展开更多
关键词 Rock discontinuities Joint roughness coefficient(JRC) Roughness characterization Principal components analysis(PCA) Machine learning
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智能网联汽车高精度部件制造趋势中“双师型”教师技术迁移能力培养路径研究
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作者 柳博 《时代汽车》 2025年第14期99-101,共3页
智能网联汽车产业高速发展,高精度部件制造技术日新月异,高校人才培养需与时俱进,“双师型”教师技术迁移能力培养迫在眉睫,研究聚焦高校在智能网联汽车高精度部件制造趋势下,围绕“双师型”教师技术迁移能力展开深入探讨,通过多维度分... 智能网联汽车产业高速发展,高精度部件制造技术日新月异,高校人才培养需与时俱进,“双师型”教师技术迁移能力培养迫在眉睫,研究聚焦高校在智能网联汽车高精度部件制造趋势下,围绕“双师型”教师技术迁移能力展开深入探讨,通过多维度分析,明确当前“双师型”教师技术迁移能力现状与不足,探索科学有效的培养路径,旨在提升高校“双师型”教师队伍素质,为智能网联汽车高精度部件制造领域输送高质量人才提供师资保障。 展开更多
关键词 Research on the Path of CULTIVATING "Double-type" Teachers' Technical Transfer Capability in the Trend of Manufacturing HIGH-PRECISION components of Intelligent Network Vehicles LIU Bo
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Differences in Chlorophyll Fluorescence Parameters, Yield and Its Components Between Different Genotypes of Wheat Under Waterlogging Conditions at Anthesis 被引量:4
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作者 Mingmei WEI Xiaoyan WANG 《Agricultural Biotechnology》 CAS 2019年第4期7-13,共7页
Waterlogging is one of the most factors limiting wheat production in the middle and lower reaches of the Yangtze River Plain of China,especially in the middle and late stages of wheat.Wheat varieties‘Jingmai102’(JM1... Waterlogging is one of the most factors limiting wheat production in the middle and lower reaches of the Yangtze River Plain of China,especially in the middle and late stages of wheat.Wheat varieties‘Jingmai102’(JM102)and‘Yangmai158’(YM158)were planted to study the dynamic changes of photosynthetic characteristics in flag leaf and the influence of waterlogging at anthesis on the yield and components and dry matter accumulation and remobilization of winter wheat in above ground.The results showed that the SPAD values slightly increased at 1 day after anthesis(d),and then kept decreasing with the increase of waterlogging time.The decrease in SPAD value was more remarkably in YM158 than that in JM102.As for the chlorophyll fluorescence parameters,the photochemical efficiency(Fv/Fm),potential activity(Fv/Fo)of photosystem II,and electronic transmission(Fm/Fo)on photosystem II increased first and then decreased with the increase of waterlogging days after anthesis.The quantum ratio of heat dissipation(Fo/Fm)had a tendency opposite to that of Fv/Fm,and the change range of JM102 was lower than that of YM158.For the grain yield and components,waterlogging at anthesis decreased the dry weight of single stem,grain yield,1 000-kernel weight,spikelet per panicle,and harvest index,and the reduction of JM102 was smaller than that of YM158.As for the accumulation and remobilization of dry matter,the accumulation of dry matter after anthesis decreased significantly under waterlogging condition(WL),and the reduction of JM102 was smaller than that of YM158.In conclusion,waterlogging at anthesis significantly affected the photosynthetic characteristics,yield and components in both varieties,but different varieties exhibited different tolerances to waterlogging stress and YM158 was more sensitive to water stress than JM102. 展开更多
关键词 Chlorophyll fluorescence parameters WATERLOGGING Grain filling rate SPAD WHEAT yield and component Dry matter accumulation and REMOBILIZATION
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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation
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作者 Xu Liang Ni-Hui Zhang +4 位作者 Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao 《Traditional Medicine Research》 2025年第2期1-15,共15页
Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants h... Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants have some differences in efficacy,but the flower buds are easily confused for similar traits.In addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal roses.Therefore,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography fingerprints.Then,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large differences.Differential compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and Meigui.Results:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the samples.Through principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four groups.Partial least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavonoid glycosides,as well as phenolic acids.Eight differential components were screened out by orthogonal partial least-squares discriminant analysis and S-plot analysis.Quantitative analyses of the eight compounds,including gallic acid,ellagic acid,hyperoside,isoquercitrin,etc.,showed that Yueji was generally richer in phenolic acids and flavonoids than Meigui,and the quality of Yueji from Shandong and Hebei was better.It is worth noting that Xinjiang rose is rich in various components,which is worth focusing on more in-depth research.Conclusion:In this study,the fingerprints of Meigui and Yueji were established.The chemical components information of roses was further improved based on non-targeted metabolomics and mass spectrometry technology.At the same time,eight differential components of Meigui and Yueji were screened out and quantitatively analyzed.The research results provided a scientific basis for the quality control and rational development and utilization of Rosae Chinensis Flos and Rosae Rugosae Flos,and also laid a foundation for the study of their pharmacodynamic material basis. 展开更多
关键词 Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics CHEMOMETRICS multiple component quantification quality evaluation
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Association analysis of an anti-obesity mechanism and key ripened Pu-erh tea bioactive components by mimicking human general tea drinking
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作者 Junyu Liu Zhengyang Song +12 位作者 Haihong Chen Wen Zeng Guirong Han Wei Li Bing Xu Yuan Lu Canyang Zhang Zhenglian Xue Bin Lü Chong Zhang Song Yang Yi Wang Xinhui Xing 《Food Science and Human Wellness》 2025年第2期450-468,共19页
Pu-erh tea,a traditional Chinese beverage,performs an anti-obesity function,but the correlation between its components and efficacy remains unknown.Here,we screened two Pu-erh teas with significant anti-obesity effica... Pu-erh tea,a traditional Chinese beverage,performs an anti-obesity function,but the correlation between its components and efficacy remains unknown.Here,we screened two Pu-erh teas with significant anti-obesity efficacies from 11 teas.In vitro experiments revealed that lipid accumulation in L02 cells and lipid synthesis in 3T3-L1 cells were significantly better inhibited by Tea-B than Tea-A.Further in vivo experiments using model mice revealed that the differences in chemical components generated two pathways in the anti-obesity efficacy and mechanism of Pu-erh teas.Tea-A changes the histomorphology of brown adipose tissue(BAT)and increases the abundance of Coriobacteriaceae_UCG_002 and cyclic AMP in guts through high chemical contents of cyclopentasiloxane,decamethyl,tridecane and 1,2,3-trimethoxybenzene,eventually increasing BAT activation and fat browning gene expression;the high content of hexadecane and 1,2-dimethoxybenzene in Tea-B reduces white adipose tissue(WAT)accumulation and the process of fatty liver,increases the abundance of Odoribacter and sphinganine 1-phosphate,inhibits the expression of lipid synthesis and transport genes.These mechanistic findings on the association of the representative bioactive components in Pu-erh teas with the anti-obesity phenotypes,gut microbes,gut metabolite structure and anti-obesity pathways,which were obtained for the first time,provide foundations for developing functional Pu-erh tea. 展开更多
关键词 ANTI-OBESITY Bioactive components Lipid metabolism Multiomics analysis Pu-erh tea
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Investigating the Mediating Role of Consumer Decision-Making Styles in the Effect of Marketing Components on Sports Consumer Satisfaction
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作者 Murat Başal Muhammet Salih Yigit 《Economics World》 2025年第2期162-174,共13页
People have been engaged in sports activities both individually and collectively for years.Sports consumption,which refers to the process that covers many issues related to sports in the form of playing,watching,liste... People have been engaged in sports activities both individually and collectively for years.Sports consumption,which refers to the process that covers many issues related to sports in the form of playing,watching,listening or reading,is a form of human behavior.The satisfaction of the four marketing components of product,price,distribution and promotion by using the leisure time of the sports consumer effectively and ensuring its continuity in the future process can be ensured by effective utilization of facilities and quality recreation activities.Consumer behaviors,which have a very complex structure,are seen in the form of choosing,buying,using and obtaining.With this study,it is aimed to determine the mediating role of consumer decision-making styles in determining the effect of marketing components in the consumption of sports activities on the satisfaction of sports consumers.In this direction,data were collected in the province of Istanbul,which was determined as the sample.Data were obtained with a questionnaire form created on Google Form.These data were analyzed in line with the model and hypotheses created with these data and it was determined that the marketing components of sports consumption have an impact on the sports consumer and it was concluded that consumer decision-making styles have a positive mediating effect in this regard. 展开更多
关键词 consumer decision sport consumption consumer satisfaction decision styles marketing components
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Land use shapes the microbial community structure by altering soil aggregates and dissolved organic matter components
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作者 Zongpeng Zhang Lijuan Hu +3 位作者 Yating Liu Yixuan Guo Shiming Tang Jie Ren 《Journal of Integrative Agriculture》 2025年第3期827-844,共18页
The agro-pastoral ecotone epitomizes the ecologically fragile semi-arid zone,where the soil microbiomes play a pivotal role in regulating its multifunctionality.However,whether and how changes in soil structure and or... The agro-pastoral ecotone epitomizes the ecologically fragile semi-arid zone,where the soil microbiomes play a pivotal role in regulating its multifunctionality.However,whether and how changes in soil structure and organic matter composition under different land uses affect microbial community structure remain unclear.Here,land-use types in the agro-pastoral ecotone,including shrubland(BF),artificial grassland(ArG),abandoned grassland(AbG),and maize farmland(MA),were chosen to explore the response relationships between soil microbial communities and the aggregates and dissolved organic matter(DOM)composition.The results showed that compared to MA,the macroaggregates in BF,AbG,and ArG were increased by 123.0,92.79,and 63.71%,respectively,while MA soil had the greatest abundance of<100μm particles.The higher aromatic carbon with high aromaticity and molecular weight in BF soil DOM contributed to its highest mineral-associated organic carbon level(12.61 g kg^(-1)),while MA soil organic carbon had highly efficient decomposition due to its high content of aliphatic and carboxy carbon,so it is prone to loss from the active carbon pools.The transition in land use from shrubland to grassland and farmland has facilitated the conversion of stable aromatic carbon to unstable carboxy carbon.The taxonomic analysis revealed that soil bacterial and fungal communities in the four land uses were dominated by Proteobacteria,Actinobacteriota,Chloroflexi,and Ascomycota.More taxonomic groups from phylum to family were enriched in BF soil.The DOM components and organic carbon are crucial variables shaping the composition of soil bacterial communities,jointly explaining 61.66% of the variance,while aggregates are important variables driving the composition of fungal communities,with an explanation rate of 20.49%.Our results suggest that DOM components and aggregates impact the soil microbial structure;and the transition in land use from agricultural land to grassland and shrubland in the agro-pastoral ecotone enhances aggregate stability,carbon sequestration potential,and microbial diversity. 展开更多
关键词 organic components microbial community aggregate stability land-use type agro-pastoral ecotone
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Multi-mode acceleration optimization control for adaptive cycle engine based on variable geometry components
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作者 Yifan WANG Haoying CHEN +1 位作者 Xuankai LIU Haibo ZHANG 《Chinese Journal of Aeronautics》 2025年第9期3-25,共23页
The acceleration and mode transition performance are two significant performances of Adaptive Cycle Engine(ACE).However,separating the processes of acceleration and mode transition will slow down the response speed of... The acceleration and mode transition performance are two significant performances of Adaptive Cycle Engine(ACE).However,separating the processes of acceleration and mode transition will slow down the response speed of thrust.Therefore,this paper proposes a multi-mode acceleration optimization control method that simultaneously performs ACE acceleration and mode transition.Firstly,an ACE component model with inlet flow characteristics was established,and the performance before and after mode transition were analyzed.Secondly,the principle of ACE acceleration optimization was analyzed,and the Front Variable Area Bypass Injector(FVABI)and Mode Selection Valve(MSV)were adopted in the acceleration process.Finally,based on the Sequential Quadratic Programming(SQP)algorithm,considering the degradation effects of engine components,we optimize the acceleration control plan for fuel and variable geometry mechanisms.The simulation results show that at the subsonic cruise point,the ACE multi-mode acceleration optimization control method can shorten the acceleration time from idle to middle state by 30.33%,and accelerate the thrust response speed by 33.72%.When the compressor flow rate of ACE deteriorates by 2% and the high-pressure turbine efficiency deteriorates by 4%,the adaptive acceleration control plan increases the high-pressure speed by 2.13% and thrust by about 6.82%;within the flight envelope,the acceleration time is reduced by more than 25%,and the thrust response speed is increased by more than 20%. 展开更多
关键词 Adaptive cycle engine Mode transition Multivariate acceleration plan Sequential quadratic planning Variable geometry components
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Therapeutic components of acupuncture stimulation based on characteristics of sensory nerve and nervous signaling pathway
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作者 Hyo-Sun Wie Seung-Nam Kim 《Journal of Integrative Medicine》 2025年第2期106-112,共7页
Acupuncture,a therapeutic practice rooted in traditional Chinese medicine and integrated with modern neuroscience,achieves its effects by stimulating sensory nerves at specific anatomical points known as acupoints.Thi... Acupuncture,a therapeutic practice rooted in traditional Chinese medicine and integrated with modern neuroscience,achieves its effects by stimulating sensory nerves at specific anatomical points known as acupoints.This review systematically explores the therapeutic components of acupuncture,emphasizing the interplay between sensory nerve characteristics and neural signaling pathways.Key factors such as acupoint location,needling depth,stimulation intensity,retention time,and the induction of sensations(e.g.,Deqi)are analyzed for their roles in neural activation and clinical outcomes.The review highlights how variations in spinal segment targeting,tissue-specific receptor activation,and stimulation modalities(e.g.,manual acupuncture,electroacupuncture,moxibustion)influence therapeutic effects.Emerging evidence underscores the significance of ion channels,dermatomes,myotomes,and genespecific pathways in mediating systemic effects.Additionally,the differential roles of mechanical,thermal and nociceptive stimuli and the temporal dynamics of sensory and immune responses are addressed.While insights from animal models have advanced our understanding,their translation to clinical practice requires further investigation.This comprehensive review identifies critical parameters for optimizing acupuncture therapy,advocating for individualized treatment strategies informed by neuroanatomical and neurophysiological principles,ultimately enhancing its precision and efficacy in modern medicine. 展开更多
关键词 Sensory nerve ACUPUNCTURE Nervous system Therapeutic component Acupuncture point MERIDIANS
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Examining gut microbiota and metabolites to clarify mechanisms of Dimocarpus longan Lour leaf components against type 2 diabetes
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作者 Piao-Xue Zheng Chun-Lian Lu +8 位作者 Yan-Li Liang Yu-Ming Ma Jia-Wen Peng Jing-Jing Xie Jia-Li Wei Si-SiChen Zhi-Dong Ma Hua Zhu Jie Liang 《World Journal of Diabetes》 2025年第7期308-327,共20页
AIM To investigate the material basis and mechanism underlying the therapeutic effect of DLC in T2DM.METHODS T2DM was triggered in rats using a high-sugar,high-fat diet alongside 35 mg/kg streptozotocin.The effect of ... AIM To investigate the material basis and mechanism underlying the therapeutic effect of DLC in T2DM.METHODS T2DM was triggered in rats using a high-sugar,high-fat diet alongside 35 mg/kg streptozotocin.The effect of DLC on the intestinal microbiota in T2DM rats was analyzed via 16S rDNA sequencing.Targeted metabolomics was conducted to evaluate the impact of DLC on the levels of nine short-chain fatty acids(SCFAs).Untargeted metabolomics examined DLC-induced alterations in fecal metabolites and associated metabolic pathways.Additionally,Spearman’s correlation analysis assessed gut microbiota and fecal metabolite relationships.RESULTS DLC significantly attenuated pathological weight loss,reduced fasting blood glucose levels,restored blood sugar homeostasis,and ameliorated dyslipidemia in T2DM rats.The 16S rDNA sequencing revealed that DLC enhanced microbial diversity and reversed intestinal dysbiosis.Targeted metabolomics indicated decreased acetic acid and propionic acid levels and increased butyric acid,isobutyric acid,and 2-methylbutyric acid levels after DLC treatment.Untargeted metabolomics revealed 57 metabolites with altered expression associated with amino acid,carbohydrate,purine,and biotin pathways.The Spearman analysis demonstrated significant links between specific gut microbiota taxa and fecal metabolites.CONCLUSION DLC may exert hypoglycemic effects by modulating intestinal flora genera,SCFA levels,and fecal metabolites. 展开更多
关键词 Dimocarpus longan Lour leaf components Type 2 diabetes 16S rDNA sequencing Short-chain fatty acids Metabolomics
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Targeted screening and profiling of massive components of colistimethate sodium by two-dimensional-liquid chromatography-mass spectrometry based on self-constructed compound database
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作者 Xuan Li Minwen Huang +11 位作者 Yue-Mei Zhao Wenxin Liu Nan Hu Jie Zhou Zi-Yi Wang Sheng Tang Jian-Bin Pan Hian Kee Lee Yao-zuo Yuan Taijun Hang Hai-Wei Shi Hongyuan Chen 《Journal of Pharmaceutical Analysis》 2025年第2期401-410,共10页
In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2... In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2D)liquid chromatography-mass spectrometry(LC-MS)method was established for screening and comprehensive profiling of compositions of the antibiotic colistimethate sodium(CMS).A high concentration of phosphate buffer mobile phase was used in the first-dimensional LC system to get the components well separated.For efficient and high-accuracy screening of CMS,a targeted method based on a self-constructed high resolution(HR)mass spectrum database of CMS components was established.The database was built based on the commercial MassHunter Personal Compound Database and Library(PCDL)software and its accuracy of the compound matching result was verified with six known components before being applied to genuine sample screening.On this basis,the unknown peaks in the CMS chromatograms were deduced and assigned.The molecular formula,group composition,and origins of a total of 99 compounds,of which the combined area percentage accounted for more than 95%of CMS components,were deduced by this 2D-LC-MS method combined with the MassHunter PCDL.This profiling method was highly efficient and could distinguish hundreds of components within 3 h,providing reliable results for quality control of this kind of complex drugs. 展开更多
关键词 Colistimethate sodium 2D-LC-MS PROFILING Targeted screening Component deduction DATABASE
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Analysis of aerosol chemical components and source apportionment during a long-lasting haze event in the Yangtze River Delta,China
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作者 Zhizhen Peng Honglei Wang +4 位作者 Minquan Zhang Yinglong Zhang Li Li Yifei Li Zelin Ao 《Journal of Environmental Sciences》 2025年第10期14-29,共16页
Based on the chemical composition data of a regional long-lasting haze event that occurred in the Yangtze River Delta(YRD)region from 17 December 2023 to 8 January 2024,the evolutionary characteristics of the chemical... Based on the chemical composition data of a regional long-lasting haze event that occurred in the Yangtze River Delta(YRD)region from 17 December 2023 to 8 January 2024,the evolutionary characteristics of the chemical components and sources of fine particulate matter(PM2.5)under different pollution levels were comparatively analyzed using PMF(Positive Matrix Factorization)and backward trajectory analysis.SNA(NO_(3)^(-),NH_(4)^(+),SO_(4)^(2-))was found to be the primary chemical component of PM2.5,making up 63.6%(clean days)to 69.7%(heavy pollution)of it.The NO_(3)^(-)concentration was 3.14(clean days)to 6.01(heavy pollution)times higher than that of SO_(4)^(2-).NO_(3)^(-),POC,Fe,Mn,Al concentrations increased,while SOC,EC,crustal elements(Ca,Si)and other water-soluble ions(WSIs)concentrations decreased as the pollution level increased.The contribution of secondary inorganics and biomass-burning emissions and industrial and ship emissions increased significantly as the pollution level increased,which accounted for 40.3%and 36.7%,respectively,in the heavy pollution stage.The contribution of traffic sources decreases gradually with increasing pollution levels,accounting for only 59.1%of the light pollution stage in the heavy pollution stage.PM_(2.5) and its main chemical components showed similar potential source distribution,located in the northwest(Fuyang,Huainan,Nanjing),south(Taizhou,Lishui,Jiande)and north(Taizhou,Yancheng).However,distinct transport routes were observed under the different air quality levels.During the heavy pollution period,the polluted air masses primarily came from the harbor regions,whereas during the light pollution period they were transported from the southeast(Taizhou)and the North China Plain. 展开更多
关键词 Yangtze River Delta region PM_(2.5)chemical components Diurnal variation Source apportionment Potential source analysis
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Embedded SCR denitration behavior in chain grate during iron ore pelletizing process: combined influence mechanism of gas components and alkali metal
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作者 Min Gan Hao Lv +7 位作者 Xiao-hui Fan Yuan Zhu Zhi-yun Ji Zeng-qing Sun Jin-hua Li Xiao-long Wang Lin-cheng Liu Yu-feng Wu 《Journal of Iron and Steel Research International》 2025年第8期2346-2358,共13页
The implementation of embedded selective catalytic reduction(SCR)denitration in chain grate during iron ore pelletizing process obviates additional flue gas heating.However,the influence of gas components and alkali m... The implementation of embedded selective catalytic reduction(SCR)denitration in chain grate during iron ore pelletizing process obviates additional flue gas heating.However,the influence of gas components and alkali metal on SCR denitration requires attention.The SCR denitration behavior in the preheating section of chain grate was investigated,and the combined influence mechanisms of H_(2)O(g),SO_(2),and potassium were revealed.The results show that the presence of H_(2)O(g)and SO_(2) in the flue gas decreases the NO conversion rate of the catalyst from 96.3%to 79.5%,while potassium adsorbed on the catalyst surface further reduces the NO conversion rate to 74.1%.H_(2)O(g),SO_(2),and potassium in the flue gas form sulfate and potassium salt on the catalyst surface,blocking the pore structure,thereby decreasing the gas adsorption capacity of the catalyst.Moreover,SO_(2) and potassium engage in competitive adsorption and reaction with NH_(3) and NO at the active sites on the catalyst surface,reducing the content and activity of the catalyst effective component.Increasing the flue gas temperature can promote the decomposition of ammonium sulfate and ammonium bisulfate on the catalyst surface,but it has little effect on potassium.Additionally,potassium will exacerbate sulfur poisoning of the catalyst.Hence,the embedded SCR denitration process requires electrostatic precipitation to eliminate the adverse impacts of potassium and thermal regime optimization to raise flue gas temperature to 350℃,thereby increasing NO conversion rate exceeding 85%. 展开更多
关键词 Iron ore pellet Chain grate Embedded selective catalytic reduction denitration Gas component Alkali metal potassium Catalyst deactivation
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