期刊文献+
共找到137,236篇文章
< 1 2 250 >
每页显示 20 50 100
“阴/阳”和“positive/negative”之多义现象的认知对比研究
1
作者 刘臻 张珊珊 梅德明 《语言教育》 2014年第4期53-56,60,共5页
多义现象是当今语言学研究的一个重要方面,从认知语言学的视角对多义现象进行对比研究是当今语义研究的一个热点,已取得了不少的研究成果,但是对于"阴/阳"和"positive/negative"这两组具有独特民族特色的字词的语... 多义现象是当今语言学研究的一个重要方面,从认知语言学的视角对多义现象进行对比研究是当今语义研究的一个热点,已取得了不少的研究成果,但是对于"阴/阳"和"positive/negative"这两组具有独特民族特色的字词的语义研究尚鲜有关注。本文从原型范畴和认知隐喻的视角,详细地分析了这两组字词的语义发展特征,发现它们的语义已经形成错综复杂的语义网状结构,既有语义重合之处,也有自己的独特之处,体现了中西文化的独特文化特征和思维特征。 展开更多
关键词 阴/阳 positive/negative 认知 多义现象 语义网络
在线阅读 下载PDF
An UPLC-MS/MS method for simultaneous determination of multiple constituents in Guizhi Fuling capsule with ultrafast positive/negative ionization switching 被引量:6
2
作者 ZHANG Rong-Hua LI Chao-Ran +4 位作者 YANG Hua LI Meng-Ning Karl W.K.Tsim LI Ping GAO Wen 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2018年第4期313-320,共8页
Guizhi Fuling capsule(GFC), a traditional Chinese medicine(TCM) with effects of promoting blood circulation and dissipating blood stasis, has been widely used in the clinic. Because of the complex matrix and various c... Guizhi Fuling capsule(GFC), a traditional Chinese medicine(TCM) with effects of promoting blood circulation and dissipating blood stasis, has been widely used in the clinic. Because of the complex matrix and various chemical structure types, quality control of GFC remains great challenge. In the present study, an ultra performance liquid chromatography hybrid triple-quadrupole mass spectrometry(UPLC-QQQ MS) method with ultrafast positive/negative ionization switching was developed for simultaneous determination of 18 bioactive components in GFC, including methyl gallate, ethyl gallate, oxypaeoniflorin, benzoic acid, albiflorin, paeonolide, paeoniflorin, 1, 2, 3, 4, 6-pentagalloylglucose, mudanpioside C, benzoyloxypaeoniflorin, benzoylpaeoniflorin, pachymic acid, amygdalin, cinnamaldehyde, paeonol, cinnamic acid, 4-hydroxybenzoic acid, and gallic acid. Separation was performed on an Agilent Zorbax Extend–C18 column(2.1 mm × 50 mm, 1.8 μm), using a gradient elution with acetonitrile and water containing 0.1% formic acid. Cholic acid was selected as the internal standard. This newly developed method was fully validated for linearity, precision, accuracy, and stability, and then applied to quality assessment of GFC. Finally, the batch-to-batch reproducibility of GFC samples was evaluated by the cosine ration and Euclidean distance method, which showed high quality consistency. The results demonstrated that the developed method provided a reasonable and powerful manner for quality control of GFC. 展开更多
关键词 Guizhi Fuling capsule(GFC) UPLC-QQQ MS Ultrafast positive/negative ionization switching Quality control
原文传递
Positive and negative risk-taking behaviors in adolescents:Distinct characteristics,interrelationships,and influencing factors
3
作者 Jun-Jie Zhang En-Na Wang 《World Journal of Psychiatry》 2025年第6期21-33,共13页
Adolescence is a crucial period marked by significant developmental changes,during which risk-taking behaviors can be both a normative part of development and a potential source of concern.However,prior research has f... Adolescence is a crucial period marked by significant developmental changes,during which risk-taking behaviors can be both a normative part of development and a potential source of concern.However,prior research has focused predominantly on the adverse aspects of risk-taking(i.e.,negative risk-taking),overlooked the positive counterpart(i.e.,positive risk-taking),and lacked a detailed examination of both.This study aims to elucidate the distinct characteristics and interrelationships of positive and negative risk-taking behaviors among adoles-cents and to identify the key factors that influence these behaviors.Through a comprehensive synthesis of theoretical and empirical literature,we explore the multifaceted nature of risk-taking,highlighting its complex influencing factors,including individual traits,family dynamics,peer influence,school environment,and broader community contexts.By identifying the shared and unique factors contributing to positive and negative risk-taking behaviors,we can enable adolescents to navigate this complex stage of life and design targeted interventions.Future research directions include the application of person-centered approaches,the implementation of longitudinal tracking and the interactive effects of influencing factors,among other aspects. 展开更多
关键词 ADOLESCENCE positive risk-taking negative risk-taking Distinct characteristics INTERRELATIONSHIPS Influencing factors
在线阅读 下载PDF
Monetary policy shocks and multi‑scale positive and negative bubbles in an emerging country:the case of India
4
作者 Oguzhan Cepni Rangan Gupta +1 位作者 Jacobus Nel Joshua Nielsen 《Financial Innovation》 2025年第1期1109-1133,共25页
We employ the Multi-Scale Log-Periodic Power Law Singularity Confidence Indicator(MS-LPPLS-CI)approach to identify positive and negative bubbles in the short-,medium,and long-term for the Indian stock market,using wee... We employ the Multi-Scale Log-Periodic Power Law Singularity Confidence Indicator(MS-LPPLS-CI)approach to identify positive and negative bubbles in the short-,medium,and long-term for the Indian stock market,using weekly data from November 2003 to December 2020.We use a nonparametric causality-in-quantiles approach to analyze the predictive impact of monetary policy shocks on bubble indicators.We find,in general,strong evidence of predictability across the entire conditional distribution for the two monetary policy shock factors,with stronger impacts for negative bubbles.Our findings have critical implications for the Reserve Bank of India,academics,and investors. 展开更多
关键词 Multi-scale positive and negative bubbles Monetary policy shocks Nonparametric causality-in-quantiles test INDIA
在线阅读 下载PDF
原型范畴观视角下的中英文多义现象认知对比研究——以“阴/阳”和“positive/negative”为例
5
作者 刘臻 《外语与翻译》 2014年第2期42-46,共5页
多义现象是当今语言学研究的一个重要方面,从认知语言学的视角对多义现象进行对比研究是当今语义研究的一个热点并取得了不少的研究成果,但是对于“阴/阳”和“positive/negative”这两组具有独特民族特色的字词的语义研究尚鲜有关... 多义现象是当今语言学研究的一个重要方面,从认知语言学的视角对多义现象进行对比研究是当今语义研究的一个热点并取得了不少的研究成果,但是对于“阴/阳”和“positive/negative”这两组具有独特民族特色的字词的语义研究尚鲜有关注。通过原型范畴和认知隐喻的视角,本文分析了这两组字词的语义发展特征,发现它们的语义已经形成错综复杂的语义网状结构,既有语义重合之处,也有自己的独特之处,体现了中西文化的独特文化特征和思维特征。 展开更多
关键词 阴/阳 positive/negative 认知 多义现象 语义网络
在线阅读 下载PDF
Analysis of Positive and Negative Influence of Constructing Xianyang Lake
6
作者 王德耀 《Journal of Landscape Research》 2009年第9期25-30,共6页
Xianyang Lake is the abbreviation of Weihe River(Xianyang Urban Area Section) Comprehensive Treatment Project,which is to build a partition wall in the middle of the 500 wide Weihe River Valley,then a 270 m wide water... Xianyang Lake is the abbreviation of Weihe River(Xianyang Urban Area Section) Comprehensive Treatment Project,which is to build a partition wall in the middle of the 500 wide Weihe River Valley,then a 270 m wide water storage channel on the north side and a 230 m wide muddy water floodway channel on the south side will be formed.Two rubber dams are constructed in the water storage channels to form a 'Xianyang Lake' with an area of 1.24×106 m2,meanwhile,along both sides of Weihe River in this section,slope protection and flood prevention as well as a series of greening and cultural landscape projects are to be constructed.This project,with flood prevention as the core,aims to improve the living environment and protect ecological environment,and realize the comprehensive treatment of river way flood-proofing,desilting,sewage purification,greening and beautification.The construction of Xianyang Lake greatly improves the image of Xianyang City and generates considerable economic,social and ecological benefits,however,it also has negative effects,such as insufficient lake water supply,original ecology being intervened by human activities,aggravating local fiscal burden,and potential threats to the flood-proofing in the lower reaches of Weihe River.The author puts forwards that 'creating a lake by damming the river' in the process of urbanization and solving the conflicts between sectional interests and integrated interests should follow natural laws and go along the track of sustainable development,which is also the orientation of future work,and the concrete reform scheme is to be further studied. 展开更多
关键词 Xianyang LAKE Weihe RIVER positive and negative INFLUENCE
在线阅读 下载PDF
Negative Coulomb drag between graphene quantum Hall edges
7
作者 SONG Junwei GAN Qikang +4 位作者 ZHU Wang WATANABE Kenji TANIGUCHI Takashi YU Geliang WANG Lei 《物理学进展》 北大核心 2026年第1期1-12,共12页
Coulomb drag refers to the phenomenon in which a current driven through one conducting layer induces a voltage nearby,electrically isolated layer sorely through interlayer Coulomb interactions between charge carriers.... Coulomb drag refers to the phenomenon in which a current driven through one conducting layer induces a voltage nearby,electrically isolated layer sorely through interlayer Coulomb interactions between charge carriers.It has been extensively studied in various systems,including parallel nanowires,double quantum wells,and double-layer graphene.Here,we report the observation of Coulomb drag in a novel system consisting of two graphene layers separated laterally by a 30 nm gap within the material plane,exhibiting behavior distinct from that in vertical graphene heterostructures.Our experiments reveal pronounced negative drag resistances under an out-of-plane magnetic field at the quantum Hall edges,reaching a maximum when the carrier densities in both graphene layers are tuned to the charge neutrality point via gate voltages.Our work establish two separate and spatially closed quantum Hall edge modes as a new platform to explore electronic interaction physics between one dimensional systems. 展开更多
关键词 negative Coulomb drag quantum Hall edges van der Waals heterostructures
在线阅读 下载PDF
Is the Higgs Field a Positive and Negative Mass Planckion Condensate, and Does the LHC Produce Extreme Dark Energy?
8
作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第2期432-456,共25页
Assuming a two-component, positive and negative mass, superfluid/supersolid for space (the Winterberg model), we model the Higgs field as a condensate made up of a positive and a negative mass, planckion pair. The con... Assuming a two-component, positive and negative mass, superfluid/supersolid for space (the Winterberg model), we model the Higgs field as a condensate made up of a positive and a negative mass, planckion pair. The connection is shown to be consistent (compatible) with the underlying field equations for each field, and the continuity equation is satisfied for both species of planckions, as well as for the Higgs field. An inherent length scale for space (the vacuum) emerges, which we estimate from previous work to be of the order of, l<sub>+</sub> (0) = l<sub>-</sub> (0) = 5.032E-19 meters, for an undisturbed (unperturbed) vacuum. Thus we assume a lattice structure for space, made up of overlapping positive and negative mass wave functions, ψ<sub>+</sub>, and, ψ<sub>-</sub>, which together bind to form the Higgs field, giving it its rest mass of 125.35 Gev/c<sup>2</sup> with a coherence length equal to its Compton wavelength. If the vacuum experiences an extreme disturbance, such as in a LHC pp collision, it is conjectured that severe dark energy results, on a localized level, with a partial disintegration of the Higgs force field in the surrounding space. The Higgs boson as a quantum excitation in this field results when the vacuum reestablishes itself, within 10<sup>-22</sup> seconds, with positive and negative planckion mass number densities equalizing in the disturbed region. Using our fundamental equation relating the Higgs field, φ, to the planckion ψ<sub>+</sub> and ψ<sub>-</sub> wave functions, we calculate the overall vacuum pressure (equal to vacuum energy density), as well as typical ψ<sub>+</sub> and ψ<sub>-</sub> displacements from equilibrium within the vacuum. 展开更多
关键词 Winterberg Model Quantum Vacuum Higgs Condensate/Composite Model Two-Component Superfluid/Supersolid Model for the Vacuum positive/negative Planckion Mass Q-Theory Non-Linear Heisenberg Spinor Theory LHC Energies Dark Energy Lattice Substructure for Space
在线阅读 下载PDF
Research on tissue section negative detection algorithm based on multispectral microscopic imaging
9
作者 Cheng Wang Qian-Qian Ge +7 位作者 Ru-Juan Wu Hao-Pu Jian Hao Chu Jia-Yi Yang Qi Chen Xiao-Qing Zhao Hua-Zhong Xiang Da-wei Zhang 《Journal of Innovative Optical Health Sciences》 2026年第2期141-158,共18页
In recent years,the rapid advancement of artificial intelligence(AI)technology has enabled AI-assisted negative screening to significantly enhance physicians'efficiency through image feature analysis and multimoda... In recent years,the rapid advancement of artificial intelligence(AI)technology has enabled AI-assisted negative screening to significantly enhance physicians'efficiency through image feature analysis and multimodal data modeling,allowing them to focus more on diagnosing positive cases.Meanwhile,multispectral imaging(MSI)integrates spectral and spatial resolution to capture subtle tissue features invisible to the human eye,providing high-resolution data support for pathological analysis.Combining AI technology with MSI and employing quantitative methods to analyze multiband biomarkers(such as absorbance differences in keratin pearls)can effectively improve diagnostic specificity and reduce subjective errors in manual slide interpretation.To address the challenge of identifying negative tissue sections,we developed a discrimination algorithm powered by MSI.We demonstrated its efficacy using cutaneous squamous cell carcinoma(cSCC)as a representative case study.The algorithm achieved 100%accuracy in excluding negative cases and effectively mitigated the false-positive problem caused by cSCC heterogeneity.We constructed a multispectral image(MSI)dataset acquired at 520 nm,600 nm,and 630 nm wavelengths.Subsequently,we employed an optimized MobileViT model for tissue classification and performed comparative analyses against other models.The experimental results showed that our optimized MobileViT model achieved superior performance in identifying negative tissue sections,with a perfect accuracy rate of 100%.Thus,our results confirm the feasibility of integrating MSI with AI to exclude negative cases with perfect accuracy,offering a novel solution to alleviate the workload of pathologists. 展开更多
关键词 Multispectral imaging artificial intelligence cSCC negative detection.
原文传递
Correlation between life satisfaction,pleasure level,and negative emotion in patients with chronic renal failure
10
作者 Lin-Lin Zhang You-Li Zhang +3 位作者 Ting Liu Jian Wang Chen Chen Xiao-Yu Wang 《World Journal of Psychiatry》 2026年第1期291-298,共8页
BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM ... BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM To explore the correlations among life satisfaction,pleasure levels,and negative emotions in patients with CRF.METHODS One hundred patients with CRF who received therapy at the First Affiliated Hospital of Jinzhou Medical University between December 2022 and February 2025 were included.The Depression,Anxiety,and Stress Scale(DASS-21),Satisfaction with Life Scale(SWLS),and Temporal Experience of Pleasure Scale(TEPS)were used to evaluate negative emotions,life satisfaction,and pleasure level,respectively.Pearson’s correlation coefficient analyzed the correlation between life satisfaction,pleasure level,and negative emotions.Linear regression analysis identified the factors affecting negative emotions.RESULTS The average DASS-21 score among patients with CRF was 51.90±2.30,with subscale scores of 17.90±1.50 for depression,18.53±1.18 for anxiety,and 15.47±2.36 for stress,all significantly higher than the domestic norm(P<0.05).The average SWLS score was 22.17±4.90.Correlation analysis revealed a negative correlation between the SWLS and total DASS-21 scores(P<0.05),but not with the individual depression,anxiety,or stress dimensions.The average TEPS score was 67.80±8.34.TEPS scores were negatively correlated with the DASS-21 score and the stress dimension(P<0.05),but not with depression or anxiety.Linear regression analysis showed that TEPS scores significantly influenced DASS-21 scores(P<0.05).CONCLUSION Patients with CRF experience high levels of negative emotions,which are negatively correlated with life satisfaction and pleasure.Furthermore,pleasure level had an impact on negative emotions. 展开更多
关键词 Chronic renal failure HEMODIALYSIS negative emotion Life satisfaction PLEASURE CORRELATION
暂未订购
Navigating climate change in carbon negative Bhutan:Insights from policy influencers and comparison to the wider Himalayan region
11
作者 Tashi DORJI Angus MORRISON-SAUNDERS David BLAKE 《Journal of Mountain Science》 2026年第2期775-797,共23页
Climate change is one of the most pressing global challenges and spares no nation.Bhutan,as the only carbon negative country in the world,is no exception and being in the Himalayas–a region warming faster than the gl... Climate change is one of the most pressing global challenges and spares no nation.Bhutan,as the only carbon negative country in the world,is no exception and being in the Himalayas–a region warming faster than the global average–further intensifies climate risks.This study explores how Bhutan navigates climate change through the perspectives of 41 policy influencers,including politicians,civil servants,and leaders from nongovernment organisations and the media.The findings are compared with scientific literature from the broader Himalayan region to identify shared vulnerabilities(e.g.,glacial lake outburst floods,water scarcity,and agricultural disruptions)and governance challenges(e.g.,financial constraints,geopolitical pressures,and gaps in policy implementation).The study reveals that Bhutan,like its Himalayan neighbours,prioritizes adaptation over mitigation due to immediate climate threats,despite its carbonnegative status.However,Bhutan faces unique pressures in upholding its dual commitments—maintaining 60%forest cover and carbon neutrality—amid competing development needs.While its Gross National Happiness(GNH)framework provides a holistic governance model,the analysis uncovers systemic barriers,including limited financing,transboundary climate risks,and uneven policy execution,which mirror regional struggles.The paper contributes to climate governance discourse by highlighting the risks of symbolic environmental pledges without robust implementation mechanisms,particularly for vulnerable mountain nations.It calls for integrated policies that bridge mitigation and adaptation,stronger regional cooperation,and equitable climate financing.The findings are relevant for policymakers in the Himalayas and international stakeholders advocating context-specific,justiceoriented climate strategies. 展开更多
关键词 BHUTAN Climate change HIMALAYAS Climate governance Carbon negative Climate resilience
原文传递
Error Analysis of Geomagnetic Field Reconstruction Model Using Negative Learning for Seismic Anomaly Detection
12
作者 Nur Syaiful Afrizal KhairulAdibYusof +5 位作者 Lokman Hakim Muhamad Nurul Shazana Abdul Hamid Mardina Abdullah Mohd Amiruddin Abd Rahman Syamsiah Mashohor Masashi Hayakawa 《Computers, Materials & Continua》 2026年第2期1338-1353,共16页
Detecting geomagnetic anomalies preceding earthquakes is a challenging yet promising area of research that has gained increasing attention in recent years.This study introduces a novel reconstruction-based modeling ap... Detecting geomagnetic anomalies preceding earthquakes is a challenging yet promising area of research that has gained increasing attention in recent years.This study introduces a novel reconstruction-based modeling approach enhanced by negative learning,employing a Bidirectional Long Short-Term Memory(BiLSTM)network explicitly trained to accurately reconstruct non-seismic geomagnetic signals while intentionally amplifying reconstruction errors for seismic signals.By penalizing the model for accurately reconstructing seismic anomalies,the negative learning approach effectively magnifies the differences between normal and anomalous data.This strategic differentiation enhances the sensitivity of the BiLSTM network,enabling improved detection of subtle geomagnetic anomalies that may serve as earthquake precursors.Experimental validation clearly demonstrated statistically significant higher reconstruction errors for seismic signals compared to non-seismic signals,confirmed through the Mann-Whitney U test with a p-value of 0.0035 for Root Mean Square Error(RMSE).These results provide compelling evidence of the enhanced anomaly detection capability achieved through negative learning.Unlike traditional classification-based methods,negative learning explicitly encourages sensitivity to subtle precursor signals embedded within complex geomagnetic data,establishing a robust basis for further development of reliable earthquake prediction methods. 展开更多
关键词 Error analysis geomagnetic field BiLSTM model negative learning earthquake precursor
在线阅读 下载PDF
Oscillation in a Class of Neutral Differential Equations with Positive and Negative Coefficients 被引量:1
13
作者 单文锐 葛渭高 郭彦平 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期321-324,共4页
The oscillatory behavior of neutral differential equation with positive and negative coefficients is investigated by mathematics analysis technique and the fixed point principle. Some sufficient conditions for oscilla... The oscillatory behavior of neutral differential equation with positive and negative coefficients is investigated by mathematics analysis technique and the fixed point principle. Some sufficient conditions for oscillation of neutral differential equation with positive and negative coefficients are obtained. 展开更多
关键词 neutral differential equation OSCILLATION fixed point principle positive and negative coefficients
在线阅读 下载PDF
Experimental and Numerical Analysis on Mechanical Behaviors of Negative Poisson’s Ratio Metamaterials
14
作者 Zeyu Han Chengbei He Liang Wang 《Computer Modeling in Engineering & Sciences》 2026年第2期234-252,共19页
Negative Poisson’s ratio materials and structures exhibit lateral expansion under tensile loading,demonstrating significant mechanical advantages over conventional materials.This study systematically investigated thr... Negative Poisson’s ratio materials and structures exhibit lateral expansion under tensile loading,demonstrating significant mechanical advantages over conventional materials.This study systematically investigated three typical two-dimensional negative Poisson’s ratio metamaterial structures(Concave honeycomb,Anti-chiral,and Anti-chiral concave honeycomb hybrid structures)through both experimental tests and numerical analysis.The test specimens were fabricated using selective laser melting(SLM)additive manufacturing technology,and the experimental test was conducted with the use of a DIC strain measurement system.The numerical studies were performed considering both static tensile loading and dynamic impact loading with different strain rates.The deformation behaviors,failure process,negative Poisson’s ratio effects,and energy absorption capacity of the three different metamaterial structures are systematically investigated,and the associated mechanical mechanisms are thoroughly revealed.Results and findings of this work could provide valuable guidance for the engineering design and application of negative Poisson’s ratio metamaterials and structures. 展开更多
关键词 negative Poisson’s ratio METAMATERIALS energy absorption failure mechanisms
在线阅读 下载PDF
A novel bHLH transcription factor LlbHLH12 negatively regulates anthocyanin biosynthesis during Lycoris longituba petal development
15
作者 Keyi Feng Hongyan Tan +4 位作者 Ling Zhou Tingting Shi Lianggui Wang Yuanzheng Yue Xiulian Yang 《Horticultural Plant Journal》 2026年第3期690-703,共14页
Flower color is an essential trait in ornamental plant breeding. Lycoris longituba is a popular ornamental plant native to central eastern China. The decrease in anthocyanin accumulation causes L. longituba petal colo... Flower color is an essential trait in ornamental plant breeding. Lycoris longituba is a popular ornamental plant native to central eastern China. The decrease in anthocyanin accumulation causes L. longituba petal color fading during flower development, which considerably affects the ornamental value of L. longituba. However, mechanisms underlying anthocyanin biosynthesis inhibition during L. longituba petal development remain unclear. In this study, three LlDFR genes were confirmed to be involved in anthocyanin biosynthesis and LlDFRc exerted the strongest promoting effect on anthocyanin accumulation. According to the correlation analysis results, LlbHLH12 exhibited the strongest negative correlation with LlDFRc. Quantitative real-time PCR analysis showed that LlbHLH12 was highly expressed during the medium bud and full bloom stages of flower development. LlbHLH12 was identified as a member of subgroup XII of bHLH transcription factor family. Subcellular localization and transcriptional activation ability assay revealed that LlbHLH12 was located in the nucleus without transcriptional activation activity. Overexpression of LlbHLH12 in Nicotiana tabacum and L. longituba inhibited anthocyanin accumulation by suppressing the expression of anthocyanin biosynthetic pathway genes. Furthermore, yeast one-hybrid, dual-luciferase, and β-glucuronidase activity assays showed that LlbHLH12 directly bound to the promoters of LlPAL and LlDFRc and suppressed their expression to inhibit anthocyanin biosynthesis. Overall, our study identified a novel bHLH repressor negatively regulating anthocyanin biosynthesis and provided new insights into the molecular mechanisms underlying color fading in L. longituba petals. 展开更多
关键词 Lycoris longituba bHLH transcription factor negative regulation Anthocyanin biosynthesis Flower color
在线阅读 下载PDF
The blow-up of solutions for porous medium equations with viscoelastic term under positive initial energy
16
作者 WU Xiu-lan ZHAO Ya-xin YANG Xiao-xin 《Applied Mathematics(A Journal of Chinese Universities)》 2026年第1期120-126,共7页
This paper deals with homogeneous Dirichlet boundary value problem to a class of porous medium equations with viscoelastic term ∂u/∂t-Δu^(m)+∫^(t)_(0)g(t-s)Δu^(m)(x,s)ds=u^(p),x∈Ω,t≥0,where p>m(m>0).We pro... This paper deals with homogeneous Dirichlet boundary value problem to a class of porous medium equations with viscoelastic term ∂u/∂t-Δu^(m)+∫^(t)_(0)g(t-s)Δu^(m)(x,s)ds=u^(p),x∈Ω,t≥0,where p>m(m>0).We prove that the weak solutions of the above problem blow up in finite time when the initial energy is positive and the function g satisfies suitable conditions.Our result generalizes that of S.A.Messaoudi in[1]. 展开更多
关键词 porous medium viscoelastic term blow up positive initial energy
在线阅读 下载PDF
Mechanisms of Gualou Beimu Yin(瓜蒌贝母饮)in suppressing the development and metastasis of triple-negative breast cancer:an integrated study based on network pharmacology,transcriptomics,and metabolomics
17
作者 JIA Ao LIU Shuang +3 位作者 GAO Tingting ZHANG Haoran GAO Wenyuan WU Xiongzhi 《Journal of Traditional Chinese Medicine》 2026年第1期149-159,共11页
OBJECTIVE:To identify the antitumor effects of Gualou Beimu Yin(瓜蒌贝母饮,GLBMY)in triple-negative breast cancer(TNBC)and to explore the underlying mechanisms.METHODS:A mouse model of breast cancer was established an... OBJECTIVE:To identify the antitumor effects of Gualou Beimu Yin(瓜蒌贝母饮,GLBMY)in triple-negative breast cancer(TNBC)and to explore the underlying mechanisms.METHODS:A mouse model of breast cancer was established and treated with GLBMY.Freeze-dried GLBMY powder was used to treat MDA-MB-231 and BT549 cells to assess the therapeutic efficacy of GLBMY against TNBC.Network pharmacology,transcriptomics and metabolomics were employed to identify the potential mechanism of GLBMY in TNBC treatment.Finally,the main regulating genes and proteins in the enriched pathways were validated by Quantitative real-time polymerase chain reaction(q PCR)and Western blotting analysis to confirm its mechanism.RESULTS:GLBMY can inhibit the growth of TNBC through apoptosis and necroptosis pathways and inhibit TNBC lung metastasis by inhibiting epithelialmesenchymal transition(EMT).Network pharmacology has elucidated the most important active ingredients(tubeimoside I,emodin,cucurbitacin,and ursolic acid)and the most critical targets[interleukin-6(IL6),signal transducer and activator of transcription 3(STAT3),mitogen-activated protein kinase 3(MAPK3)]of GLBMY in treating TNBC.RNA-seq revealed that GLBMY affected the nuclear factor kappa-light-chain-enhancer of activated B cells,rat sarcoma virus,and MAPK signalling pathways.Metabolomics revealed that the metabolites mainly affected by GLBMY were L-(+)-lactic acid,isocitric acid,benzoic acid and indoxyl sulfate.Subsequent experiments demonstrated that GLBMY can inhibit EMT in TNBC through the MAPK/ERK pathway and inhibit the proliferation and progression of TNBC through the IL6-STAT signalling pathway.CONCLUSIONS:We confirmed that GLBMY inhibits the development and metastasis of TNBC through the MAPK/Erk and IL6-STAT signalling pathways.GLBMY shows promise as a long-term supplementary or alternative therapy for TNBC,offering new insights for TNBC treatment. 展开更多
关键词 triple negative breast neoplasms epithelialmesenchymal transition network pharmacology metabolomics Gualou Beimu Yin
原文传递
A conceptual analysis of reflective supervision for creating a positive intensive care practice environment
18
作者 Mpho Grace Chipu 《International Journal of Nursing Sciences》 2026年第1期88-95,共8页
Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant... Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant’s eight-step concept analysis approach was utilized to identify and define the attributes,antecedents,and consequences of reflective supervision in the ICU.An extensive literature search was conducted across various databases,including Google Scholar,CINAHL,PubMed.Articles published from 2005 to 2025 were identified.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020 statement to indicate the included articles and extract related data based on relevance.Results Forty articles were included in the analysis.The identified attributes included the supervisor-supervisee relationship,effective communication,teamwork,collaborations,reflection,competencies,feedback,continuous support,and autonomous choice.The identified antecedents included participation,supportive supervision,flexibility,open-door policy,training,and motivation.Consequences impacting the success of reflective supervision were identified as promotion of resiliency,autonomy,work-life balance,self-awareness,increased self-esteem,professional development,critical thinking,increased job satisfaction,and enhanced commitment.Conclusions Reflective supervision is a complex professional self-care strategy that enhances ICU practice,by promoting nurses’well-being,self-awareness,therapeutic skills,and professional development. 展开更多
关键词 Concept analysis Intensive Care Unit NURSING positive environment Reflective supervision
暂未订购
Leader-following positive consensus of heterogeneous switched multi-agent systems with average dwell time switching
19
作者 Kaiming Li Wei Xing +1 位作者 Haoyue Yang Junfeng Zhang 《Control Theory and Technology》 2026年第1期66-81,共16页
This paper focuses on the leader-following positive consensus problems of heterogeneous switched multi-agent systems.First,a state-feedback controller with dynamic compensation is introduced to achieve positive consen... This paper focuses on the leader-following positive consensus problems of heterogeneous switched multi-agent systems.First,a state-feedback controller with dynamic compensation is introduced to achieve positive consensus under average dwell time switching.Then sufficient conditions are derived to guarantee the positive consensus.The gain matrices of the control protocol are described using a matrix decomposition approach and the corresponding computational complexity is reduced by resorting to linear programming and co-positive Lyapunov functions.Finally,two numerical examples are provided to illustrate the results obtained. 展开更多
关键词 Heterogeneous switched multi-agent systems positive consensus Linear programming
原文传递
Establishing positive feedback between polysulfide conversion and lithium-ion migration in Li-S battery
20
作者 Bin Han Xingfa Liu +5 位作者 Yue Chen Kaicheng Yang Ding Ding Kai Chen Jun Xu Qingchi Xu 《Journal of Energy Chemistry》 2026年第2期207-216,I0006,共11页
The performance of lithium-sulfur batteries(LSBs)is severely limited by a detrimental negative feedback loop:sluggish polysulfide conversion kinetics lead to Li_(2)S accumulation,which further hinders lithiumion trans... The performance of lithium-sulfur batteries(LSBs)is severely limited by a detrimental negative feedback loop:sluggish polysulfide conversion kinetics lead to Li_(2)S accumulation,which further hinders lithiumion transport and exacerbates capacity decay.To address this,we propose a positive feedback strategy that simultaneously enhances lithium polysulfides(LiPSs)conversion and lithium-ion diffusion through a rationally designed separator.By modifying the separator with phosphorus-doped two-dimensional hollow holey carbon nanosheets(Hollow HCNS),we establish an interconnected network where rapid LiPSs confinement and conversion within the hollow cavities promote efficient lithium-ion transport,while the improved ion flux further accelerates reaction kinetics.This mutual reinforcement mechanism ensures stable cycling by suppressing the shuttle effect and promoting uniform Li_(2)S deposition,as verified by in situ spectroscopic and electrochemical analysis.The resulting LSBs exhibit high-rate capability,ultralow capacity decay,and exceptional stability under high sulfur loading.This work presents a general approach to overcoming the persistent negative feedback problem in high-energy battery systems by synergistically optimizing catalytic conversion and ionic transport. 展开更多
关键词 Lithium-sulfur batteries Hollow holey carbon nanosheet positive feedback
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部