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Determinations of the Configuration of C-20 in Derivatives of Adynerin Using DFT/HF Methods 被引量:3
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作者 HUA Yan REN Jie +1 位作者 CHEN Chang-xiang ZHU Hua-jie 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第5期592-597,共6页
The configurations of C-20 in derivatives of novel 5α-adynerin type,co-existing glycoside in pair,were identified with the calculated chemical shifts of carbon at the B3LYP/6-311+G(2d,p)level.These glycosides are ... The configurations of C-20 in derivatives of novel 5α-adynerin type,co-existing glycoside in pair,were identified with the calculated chemical shifts of carbon at the B3LYP/6-311+G(2d,p)level.These glycosides are unusual cardic aglycones without the common olefin bond in ring E. 展开更多
关键词 Configuration determination Adynerin derivative B3LYP GIAO NMR computation
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Essential Regulation of YAP1 in Fate Determinations of Spermatogonial Stem Cells and Male Fertility by Interacting with RAD21 and Targeting NEDD4 in Humans and Mice
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作者 Chunyun Li Wei Chen +4 位作者 Yinghong Cui Dong Zhang Qingqing Yuan Xing Yu Zuping He 《Research》 2025年第3期556-573,共18页
Spermatogenesis is a sophisticated biological process by which spermatogonial stem cells(SSCs)undergo self-renewal and differentiation into spermatozoa.Molecular mechanisms underlying fate determinations of human SSCs... Spermatogenesis is a sophisticated biological process by which spermatogonial stem cells(SSCs)undergo self-renewal and differentiation into spermatozoa.Molecular mechanisms underlying fate determinations of human SSCs by key genes and signaling pathways remain elusive.Here,we report for the first time that Yes1-associated transcriptional regulator(YAP1)is required for fate determinations of SSCs and male fertility by interacting with RAD21 and targeting NEDD4 in humans and mice.YAP1 was mainly located at cell nuclei of human SSCs.YAP1 silencing resulted in the decreases in proliferation and DNA synthesis as well as an enhancement in apoptosis of human SSCs both in vivo and in vitro.RNA sequencing and real-time polymerase chain reaction assays identified NEDD4 as a target of YAP1,and NEDD4 knockdown inhibited the proliferation of human SSCs and increased their apoptosis.Furthermore,YAP1 interacted with RAD21 to regulate NEDD4 transcription in human SSCs.Importantly,YAP1 abnormalities were found to be associated with non-obstructive azoospermia(NOA)as manifested as lower expression level of YAP1 in testicular tissues of NOA patients and YAP1 single-nucleotide variants(SNVs)in 777 NOA patients.Finally,Yap1 germline conditional knockout(cKO)mice assumed mitotic arrest,low sperm count,and motility.Collectively,these results highlight a critical role of YAP1 in determining the fate determinations of human SSCs and male infertility through the YAP1/RAD21/NEDD4 pathway.This study provides new insights into the genetic regulatory mechanisms underlying human spermatogenesis and the pathogenesis of NOA,and it offers new targets for gene therapy of male infertility. 展开更多
关键词 fate determinations YAP signaling pathways spermatogonial stem cells sscs undergo Spermatogonial Stem Cells Male Fertility targeting nedd RAD
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AN INVESTIGATION OF PEDIGREES OF 110 PATIENTS WITH GRAVES' DISEASE AND THE CLINICAL SIGNIFICANCE OF DETERMINATIONS OF ANTITHYROID ANTIBODIES OF THEIR FIRST-DEGREE RELATIVES
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作者 王德全 王洁贞 +2 位作者 任建民 周显腾 彭万程 《Chinese Medical Journal》 SCIE CAS CSCD 1994年第11期19-23,共5页
Eight hundred and ten pedigree members of 110 patients with Graves' disease were studied. In 700 first-egree relatives, inquiry of medical history, physical examination (including eyes, thyroid, heart rate, etc), ... Eight hundred and ten pedigree members of 110 patients with Graves' disease were studied. In 700 first-egree relatives, inquiry of medical history, physical examination (including eyes, thyroid, heart rate, etc), thyroid function tests (serum T3, T4 and TSH levels), determinations of thyroglobulin antibodies (TgAb) and thyroid microsomal antibodies (TmAb) were performed. For male (female) probands, the incidence of Graves' disease in male (female) first-degree relatives were investigated and their serum TgAb and TmAb were analysed. The incidence of these two kinds of autoantibodies in the male (female) first-egree relatives of familial and nonfamilial Graves' disease were analysed. Eighteen persons with positive TgAb and TmAb from 5 pedigrees had been followed up one year after initial determinations. Our results suggest that the positive rates of TgAb and TmAb in the first-egree relatives of Graves' disease were coincident with the incidence of Graves' disease, and the positive results of TgAb and TmAb in the first-egree relatives of Graves' disease may be an indicator of pre-raves' disease or pre-utoimmune thyroid diseases. 展开更多
关键词 In AN INVESTIGATION OF PEDIGREES OF 110 PATIENTS WITH GRAVES DISEASE AND THE CLINICAL SIGNIFICANCE OF determinations OF ANTITHYROID ANTIBODIES OF THEIR FIRST-DEGREE RELATIVES 110 than
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Posterior enhancer(p-Enh)maintains early neuromesodermal progenitors bi-potency during gastrulation
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作者 Panpan Mi Yingying Chen +7 位作者 Fengxiang Tan Penglei Shen Yun Yang Mingzhu Wen Yun Qian Jichang Wang Naihe Jing Xianfa Yang 《Cell Regeneration》 2026年第1期69-85,共17页
Vertebrate axis patterning requires precise control of the differentiation of neuromesodermal progenitors(NMPs),which generate spinal cord(SC)and presomitic mesoderm(PSM).Previously,we identified a gastrula-premarked ... Vertebrate axis patterning requires precise control of the differentiation of neuromesodermal progenitors(NMPs),which generate spinal cord(SC)and presomitic mesoderm(PSM).Previously,we identified a gastrula-premarked posterior enhancer(p-Enh)that is essential for posterior tissue development by regulating somite and SC in organogenetic embryos,while its role in early NMPs cells remains elusive.Here,using a highly efficient in vitro differentiation system,we found that the genetic removal of p-Enh leads to the aberrantly up-regulated PSM-related genes during both PSM and SC differentiation.Time-resolved transcriptomic analysis and experimental characterization revealed the activated PSM transcriptomic signature arose from disorganized NMPs composition,with an over-representation of the T^(high)SOX2^(low)NMPs subtype.Besides,through a newly developed bioinformatic tool,ST-Pheno,which effectively bridges the in vitro samples to in vivo embryonic phenotypes within spatiotemporal context,we determined that the over-produced T^(high)SOX2^(low)NMPs subtype is predominantly enriched in the anterior primitive streak and adjacent mesoderm region at E7.5,which may disrupt the proper development of NMPs towards prospective PSM and SC,ultimately leading to the posterior development failure.In summary,this study demonstrates a critical role of p-Enh in regulating NMPs subtype composition,which will broaden the molecular understanding of mammalian embryogenesis. 展开更多
关键词 GASTRULATION Neuromesodermal progenitors ENHANCER Cell fate determination ST-Pheno
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Establishment of a Determination Method for Fruit Texture in Chieh-qua Using Texture Analyzer
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作者 Ying WANG Xuan DU Na LIU 《Agricultural Biotechnology》 2026年第1期54-59,共6页
[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and pun... [Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and puncture,the index data of the fruit were obtained by setting different trigger forces,deformation levels,test speeds,as well as puncture speeds and puncture depths.The data included TPA hardness,adhesiveness,springiness,cohesiveness,gumminess,chewiness,resilience,as well as skin hardness,skin toughness,flesh hardness,fracturability,and compactness.[Results]Different deformation levels had a significant impact on all parameters.Hardness,adhesiveness,gumminess and chewiness showed a trend of first increasing and then decreasing with the deformation level increasing.When the deformation level was 30%,the adhesiveness,gumminess and chewiness reached their maximum values.When the deformation level was 50%,TPA hardness reached its maximum.When the compression speed was 3 mm/s,the measured values of TPA hardness,adhesiveness,chewiness,and resilience were at their maximums.The skin hardness varied significantly under different trigger forces.When the trigger force was 15 g,the skin hardness reached a maximum value of 944.63 g,and the skin toughness,flesh hardness,fracturability,and compactness also reach their maximum values respectively.When the puncture depth was 12 mm,the flesh hardness and skin toughness reached their maximums of 682.51 g and 1.82 mm,respectively.In the TPA mode,the flesh hardness of chieh-qua showed an extremely significant negative correlation with springiness,cohesiveness,and resilience(P<0.01).The fruit fracturability detected by puncture had an extremely significant positive correlation with compactness(P<0.01).[Conclusions]The evaluation method for measuring chieh-qua texture by combining TPA and the puncture mode could accurately and quantitatively reflect the differences in the flesh texture quality of chieh-qua.The optimal parameters for texture measurement of chieh-qua fruit were determined as a 15 g trigger force with 50%deformation and a 3 mm/s compression speed in TPA mode,and a 15 g trigger force with a 12 mm puncture depth in puncture mode.Puncture speed was found to have no significant effect on the texture indices of chieh-qua. 展开更多
关键词 CHIEH-QUA Texture analyzer Texture quality Determination method
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Cell-autonomous determination of sex dimorphism in neuromodulation of a gynandromorphic Zebra Finch
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作者 Yangyang Cao Zhiwen Huang +5 位作者 Wenxiang Hu Yutao Zhang Kun Zhang Jiachun Zuo Yan Zou Wei Meng 《Avian Research》 2026年第1期157-171,共15页
Gynandromorphs,rare in vertebrates,exhibit distinct sex-determining gene expression on each side of the body despite sharing a uniform hormonal environment.This provides a unique opportunity to investigate the respect... Gynandromorphs,rare in vertebrates,exhibit distinct sex-determining gene expression on each side of the body despite sharing a uniform hormonal environment.This provides a unique opportunity to investigate the respective roles of genes and hormones in sex determination.We accidently obtained a gynandromorphic Zebra Finch with a male-female chimeric appearance but only with an ovary-like gonad.Its plasma estradiol was significantly higher than that of age-matched females,and its sexual partner preference was also feminine.Although it did not sing like males,its calls showed masculinization.In the brain on one side of the body with male plumage,the area of song motor nucleus,the robust nucleus of the arcopallium(RA),and the excitatory synaptic transmission of RA projection neurons showed masculinization.Transcriptome analysis revealed that genes related to cholinergic neuron function were significantly upregulated in the masculinized side of brain.Moreover,there were extensive and consistent expression differences of neuroactive substance receptor genes in both sides of body,indicating that cell-autonomous determination plays a key role in sex dimorphism of neuromodulation. 展开更多
关键词 AVIAN Cell-autonomous determination GYNANDROMORPH NEUROMODULATION Sex dimorphism Sex hormone Synaptic transmission Zebra Finch
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IMPROVEMENT ON HANKEL DETERMINANT BOUNDS FOR SPECIFIC HOLOMORPHIC FUNCTIONS
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作者 Huo TANG Muhammad ABBAS +1 位作者 Reem K.ALHEFTHI Muhammad ARIF 《Acta Mathematica Scientia》 2026年第1期39-61,共23页
In recent years,researchers have extensively investigated the Hankel determinant,which consists of coefficients appearing in a holomorphic function’s Taylor-Maclaurin series.Hankel matrices are widely used in Markov ... In recent years,researchers have extensively investigated the Hankel determinant,which consists of coefficients appearing in a holomorphic function’s Taylor-Maclaurin series.Hankel matrices are widely used in Markov processes,non-stationary signals,and other mathematical disciplines.The aim of the current research article is to first improve the bounds of coefficient-related problems by employing the well-known Carathéodory function.The problems that we are going to improve were obtained by Tang et al.The sharp estimates of the most difficult problem of geometric function theory known as the third-order Hankel determinant are also contributed here.Zalcman and Fekete-Szegöinequalities are also studied here for the defined family of holomorphic functions. 展开更多
关键词 holomorphic function Carathéodory function Hankel determinant Zalcman inequality
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Spatiotemporal Variability of Influencing Factors on Tuberculosis Incidence in Jiangsu Province,China during 2011−2021
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作者 Yifan Tang Tenglong Li +7 位作者 Cheng Chen Kai Wang Mingming Chen Junhui Lin Sifan Wang Limei Zhu Chengxiu Ling Qiao Liu 《Biomedical and Environmental Sciences》 2026年第2期234-238,共5页
Tuberculosis(TB),one of the oldest infectious diseases caused by Mycobacterium tuberculosis,poses a considerable challenge to global public health.There are approximately 10 million new TB cases worldwide annually,and... Tuberculosis(TB),one of the oldest infectious diseases caused by Mycobacterium tuberculosis,poses a considerable challenge to global public health.There are approximately 10 million new TB cases worldwide annually,and TB claims the lives of nearly 3 million people each year,making it one of the leading causes of death from a single infectious disease[1].China ranks third globally in terms of TB burden,with approximately 733,000 TB cases reported in 2023[2].Based on the ecological model of health determinants developed by Whitehead and Dahlgren,health determinants can be classified into direct causes. 展开更多
关键词 tuberculosis incidence infectious diseases influencing factors mycobacterium tuberculosisposes spatiotemporal variability China ecological model health determinants jiangsu province
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Direct position determination based on rotating single-baseline interferometer for multiple time-frequency aliased sources
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作者 Yuan ZHANG Guizhou WU +2 位作者 Fucheng GUO Zihan YAO Min ZHANG 《Chinese Journal of Aeronautics》 2026年第2期389-401,共13页
Rotating Single-Baseline Interferometer(RSBI)systems have attracted considerable attention for Direct Position Determination(DPD)due to their simplicity and high localization accuracy.Nevertheless,the growing complexi... Rotating Single-Baseline Interferometer(RSBI)systems have attracted considerable attention for Direct Position Determination(DPD)due to their simplicity and high localization accuracy.Nevertheless,the growing complexity of electromagnetic environments has led to scenarios with multiple time-frequency aliased sources,rendering conventional DPD methods for RSBI systems ineffective.Previous studies have predominantly concentrated on deploying antenna arrays and applying related signal-processing techniques for localization.Typically,these approaches necessitate that the number of physical antennas exceeds the number of sources.For RSBI systems already in practical operation,this would entail the installation of additional physical antennas,which implies equipment recycling and hardware upgrades.In numerous cases,such modifications are unfeasible.This paper proposes a novel Relative Offset-based Direct Position Determination(RO-DPD)method for RSBI systems that can handle multiple time-frequency aliased sources.The proposed method overcomes the challenge of simultaneous positioning without requiring hardware modifications by leveraging time accumulation and algorithmic enhancements.The implementation of the method involves three key steps.Firstly,the rotation of the interferometer is synthesized into a virtual Uniform Circular Array(UCA).Secondly,a novel estimation variable,termed relative offset,is introduced.The variable serves as an intermediate parameter to establish correlation equations between the positions of multiple time-frequency aliased sources and the intercepted signals.Thirdly,the relative offset model in the UCA is transformed into a virtual Uniform Linear Array(ULA)model,from which the cost function can be derived via the Spatial Smoothing(SS)MUSIC algorithm.Theoretical analysis and simulation results verify the effectiveness of the proposed method.Compared with traditional approaches,the RO-DPD method maintains the low complexity of RSBI systems while demonstrating robust performance in complex electromagnetic environments. 展开更多
关键词 Rotating single-baseline interferometer Direct position determination Uniform circular array Array processing
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Research on the visualization method of lithology intelligent recognition based on deep learning using mine tunnel images
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作者 Aiai Wang Shuai Cao +1 位作者 Erol Yilmaz Hui Cao 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期141-152,共12页
An image processing and deep learning method for identifying different types of rock images was proposed.Preprocessing,such as rock image acquisition,gray scaling,Gaussian blurring,and feature dimensionality reduction... An image processing and deep learning method for identifying different types of rock images was proposed.Preprocessing,such as rock image acquisition,gray scaling,Gaussian blurring,and feature dimensionality reduction,was conducted to extract useful feature information and recognize and classify rock images using Tensor Flow-based convolutional neural network(CNN)and Py Qt5.A rock image dataset was established and separated into workouts,confirmation sets,and test sets.The framework was subsequently compiled and trained.The categorization approach was evaluated using image data from the validation and test datasets,and key metrics,such as accuracy,precision,and recall,were analyzed.Finally,the classification model conducted a probabilistic analysis of the measured data to determine the equivalent lithological type for each image.The experimental results indicated that the method combining deep learning,Tensor Flow-based CNN,and Py Qt5 to recognize and classify rock images has an accuracy rate of up to 98.8%,and can be successfully utilized for rock image recognition.The system can be extended to geological exploration,mine engineering,and other rock and mineral resource development to more efficiently and accurately recognize rock samples.Moreover,it can match them with the intelligent support design system to effectively improve the reliability and economy of the support scheme.The system can serve as a reference for supporting the design of other mining and underground space projects. 展开更多
关键词 rock picture recognition convolutional neural network intelligent support for roadways deep learning lithology determination
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Pressure calibrations of high-pressure large-volume presses at HPSTAR
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作者 Yongjiang Xu Peiyan Wu +17 位作者 Sheng Shang Xue Wang Taihang Li Shuchang Gao Shijie Lv Hang Cheng Qianzhi Xu Shang Lei Jiajia Feng Lei Zhao Wim van Westrenen Takayuki Ishii Bin Chen Lei Su Yang Ding Wenge Yang Ho-Kwang Mao Yanhao Lin 《Matter and Radiation at Extremes》 2026年第1期111-130,共20页
Large-volume presses(LVPs)are widely utilized in diverse research fields—including high-pressure physics,chemistry,materials science,and Earth and planetary sciences—to investigate the physical and chemical properti... Large-volume presses(LVPs)are widely utilized in diverse research fields—including high-pressure physics,chemistry,materials science,and Earth and planetary sciences—to investigate the physical and chemical properties of materials under extreme high-pressure and hightemperature conditions.A prerequisite for achieving reproducible property measurements is the determination and control of pressure within experimental setups.However,the lack of precise pressure calibration in LVPs hinders the broader application of such devices in ultrahigh-pressure studies.This study employs a suite of standard phase transition-based pressure markers—comprising metallic conductors,semiconductors,and minerals—through both in situ and ex situ identification approaches,to establish pressure calibration curves ranging from 0.4 to>30 GPa for various types of LVP installed at the Center for High Pressure Science and Technology Advanced Research(HPSTAR),Beijing,including piston–cylinder,cubic,and multi-anvil presses.The results provide a unified and traceable pressure reference for highpressure experiments conducted at HPSTAR,while also offering technical guidance and calibration standards for other researchers utilizing similar LVP systems,thereby enabling more consistent comparison between different laboratories.This work facilitates the advancement of LVP research toward broader applications in higher-pressure regimes. 展开更多
关键词 CHEMISTRY earth planetary sciences pressure calibration high pressure physics materials science investigate physical chemical properties materials determination control pressure
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Modernization of traditional Chinese medicine in cancer therapy:“3 D”innovative Chinese medicine
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作者 Hui Liu Yunxiao Ge Zigang Dong 《Chinese Journal of Natural Medicines》 2026年第2期189-202,共14页
Traditional Chinese medicine(TCM)has garnered increasing attention globally,with its modernization becoming a prominent research focus both within China and internationally.However,the lack of a precise definition for... Traditional Chinese medicine(TCM)has garnered increasing attention globally,with its modernization becoming a prominent research focus both within China and internationally.However,the lack of a precise definition for TCM modernization has hindered clear guidance for its development.Additionally,cancer remains a significant global public health challenge,largely untreatable with current methods.Therefore,a comprehensive understanding of TCM modernization is crucial for its evolution,revolution,drug discovery,and cancer therapy.This study provides an overview of the history,theory,characteristics,and evolution of TCM,highlighting its potential in cancer prevention and treatment.We propose a definition for TCM modernization,innovative Chinese medicine(ICM),and elucidate strategies to elevate TCM from a supporting role to a leading one.Electronic databases such as PubMed,Web of Science,ScienceDirect,and Clinical Trials were utilized to retrieve relevant literature spanning from 1979 to 2024,with most publications being from the last five years,using keywords like“Traditional Chinese medicine”,“Cancer”,“Mechanism”,and“Clinical trial”.In this study,we introduce the theory of TCM modernization following target identification and initial compound screening:ICM,defined by“3 D”elements:definite active ingredient composition and content,determined functional mechanism,and detection through evidence-based medicine.Overall,the“3 D”definition of ICM will establish a standard for ICM,accelerate TCM modernization,enhance drug discovery targeting cancer and various human diseases,and benefit patients worldwide. 展开更多
关键词 Traditional Chinese medicine Innovative Chinese medicine Definite active ingredient composition and content Determined functional mechanism Detection through evidence-based medicine Cancer therapy Drug discovery
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Content Determination of Zhuang Medicine Sauropus spatulifolius Beille from Guangxi
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作者 Lixin SUN Yongshan JIN +8 位作者 Wenjing YANG Aipeng LI Yarong WEI Liangna SU Chengxu CHEN Fangyuan SHEN Yanmin LU Suoyi HUANG Lixiang LU 《Medicinal Plant》 2026年第1期1-4,共4页
[Objectives]To determine the content of Zhuang medicine Sauropus spatulifolius Beille from Guangxi.[Methods]The amino acid content of S.spatulifolius Beille was determined by ultraviolet spectrophotometry(UVs).The con... [Objectives]To determine the content of Zhuang medicine Sauropus spatulifolius Beille from Guangxi.[Methods]The amino acid content of S.spatulifolius Beille was determined by ultraviolet spectrophotometry(UVs).The content of kaempferol-3-O-gentiobioside in S.spatulifolius Beille was determined by liquid chromatography-mass spectrometry(LC-MS).Pesticide residues in S.spatulifolius Beille were detected by gas chromatography-mass spectrometry(GC-MS).Heavy metal elements arsenic(As),cadmium(Cd),and lead(Pb)in S.spatulifolius Beille were detected by inductively coupled plasma mass spectrometry(ICP-MS).[Results]The amino acid content in S.spatulifolius Beille was 3.233 mg/g,with a relative standard deviation(RSD)of 0.36%.The content of kaempferol-3-O-gentiobioside was 1.15μg/mL.No pesticide residues or heavy metals were detected in the S.spatulifolius Beille medicinal material.[Conclusions]This study improves the quality control system for S.spatulifolius Beille and provides a reference basis for the quality standard control of Zhuang medicine S.spatulifolius Beille from Guangxi. 展开更多
关键词 Zhuang medicine Sauropus spatulifolius Beille Liquid chromatography-mass spectrometry(LC-MS) Gas chromatography-mass spectrometry(GC-MS) Inductively coupled plasma mass spectrometry(ICP-MS) Content determination
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Comparison of Artificial Neural Networks with Partial Least Squares Regression for Simultaneous Determinations by ICP-AES 被引量:1
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作者 KHAYATZADEH MAHANI, Mohamad CHALOOSI, Marzieh +2 位作者 GHANADI MARAGHEH, Mohamad KHANCHI, Ali Reza AFZALI, Dariush 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第11期1658-1662,共5页
Simultaneous determination of several elements (U, Ta, Mn, Zr and W) with inductively coupled plasma atomic emission spectrometry (ICP-AES) in the presence of spectral interference was performed using chemometrics... Simultaneous determination of several elements (U, Ta, Mn, Zr and W) with inductively coupled plasma atomic emission spectrometry (ICP-AES) in the presence of spectral interference was performed using chemometrics methods. True comparison between artificial neural network (ANN) and partial least squares regression (PLS) for simultaneous determination in different degrees of overlap was investigated. The emission spectra were recorded at uranium analytical line (263.553 nm) with a 0.06 nm spectral window by ICP-AES. Principal component analysis was applied to data and scores on 5 dominant principal components were subjected to ANN. A 5-5-5 (input, hidden and output neurons) network was used with linear transfer function after both hidden and output layers. The PI,S model was trained with five latent variables and 20 samples in calibration set. The relative errors of predictions (REP) in test set were 3.75% and 3.56% for ANN and PLS respectively. 展开更多
关键词 CHEMOMETRICS artificial neural network partial least square simultaneous determination
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Quantitative analysis of FRET assay in biology New developments in protein interaction affinity and protease kinetics determinations in the SUMOylation cascade 被引量:1
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作者 Yan LIU Yang SONG Ling JIANG Jiayu LIA 《Frontiers in Biology》 CAS CSCD 2012年第1期57-64,共8页
Forster resonance energy transfer (FRET) techniques have been widely used in biological studies in vitro andin vivo and are powerful tools for elucidating protein interactions in many regulatory cascades. FRET occur... Forster resonance energy transfer (FRET) techniques have been widely used in biological studies in vitro andin vivo and are powerful tools for elucidating protein interactions in many regulatory cascades. FRET occurs between oscillating dipoles of two fluorophores with overlapping emission and excitation wavelengths and is dependent on the spectroscopic and geometric properties of the donor-acceptor pair. Various efforts have been made to develop quantitative FRET methods to accurately determine the interaction affinity and kinetics parameters. SUMOylation is an important post-translational protein modification with key roles in multiple biological processes. Conjugating SUMO to substrates requires an enzymatic cascade. Sentrin/SUMO-specific proteases (SENP) act as endopeptidases to process the pre-SUMO or an isopeptidase to deconjugate SUMO from its substrate. Here we also summarize recent developments of theoretical and experimental procedures for determining the protein interaction dissociation constant, Kd, and protease kinetics parameters, kcat and Kin, in the SUMOylation pathway. The general principles of these quantitative FRET-based measurements can be applied to other protein interactions and proteases. 展开更多
关键词 quantitative FRET analysis protein affinity determination kinetics analysis
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Prevalence and determinations of physical inactivity among public hospital employees in Shanghai, China: a cross-sectional study
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作者 Xinjian Li Minna Cheng +2 位作者 Hao Zhang Ting Ke Yisheng Chen 《Frontiers of Medicine》 SCIE CAS CSCD 2015年第1期100-107,共8页
This study aims to explore the prevalence and determinations of physical inactivity among hospital employees in Shanghai, China. A cross-sectional study of 4612 employees aged 19 to 68years was conducted through strat... This study aims to explore the prevalence and determinations of physical inactivity among hospital employees in Shanghai, China. A cross-sectional study of 4612 employees aged 19 to 68years was conducted through stratified cluster sampling from different classes of Shanghai hospitals in 2011. The total physical activity was evaluated using the metabolic equivalent according to the Global Physical Activity Questionnaire. Among the participants, 38.5%, 32.3%, and 64.6% of the employees are inactive at work, commuting, and taking leisure time, respectively. Up to 41.8% of the men and 37.8% of the women (P = 0.012) are physically inactive. When the age and educational level are adjusted, male doctors and medical technicians show a higher percentage of physical inactivity than male workers in logistics (P = 0.001). Among females, employees who are working in second- and third-class hospitals show a higher proportion of physical inactivity than those who are working in community health care centers. Logistic regression analyses show that the odds ratios (ORs) of leisure-time physical inactivity associated with the intensity of physical activity at work are 2.259, 2.897, and 4.266 for men (P 〈 0.001) and 2.456, 3.259, and 3.587 for women (P 〈 0.001), respectively. The time during commuting activities is significantly associated with leisure-time physical inactivity in either sex (OR = 2.116 for men and 2.173 for women, P 〈 0.001). Hospital employees, particularly doctors and medical technicians, show a higher proportion of physical inactivity than other inhabitants in Shanghai. The time and intensity of activity at work and commuting are associated with leisure-time activities. 展开更多
关键词 physical inactivity PREVALENCE determination employee public hospital cross-sectional study
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Comparison of direct and indirect determinations of dynamic ventilation rate in a modern dairy free stall barn
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作者 Bing Zou Albert J.Heber +3 位作者 Zhengxiang Shi Songhuai Du Yaomin Jin Teng Teeh Lim 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2020年第6期41-46,共6页
Reliable estimation of the ventilation rate(VR)in intensive livestock buildings is necessary for studying building environmental control strategies and predicting indoor air quality and air emissions.As direct air exc... Reliable estimation of the ventilation rate(VR)in intensive livestock buildings is necessary for studying building environmental control strategies and predicting indoor air quality and air emissions.As direct air exchange measurements are time-consuming and expensive,it is environmentally inefficient to measure livestock building VR continuously in practice.Hence,indirect VR estimation methods have been widely used in modelling environmental control and air emissions,and also to measure airflow in the field.The accuracy of indirect measurement methods needs to be evaluated by comparing with direct measurements.In this study,the direct and indirect methods of determining hourly and daily mean VRs were applied to a mechanically-ventilated dairy free stall barn monitored by the 24-month National Air Emissions Monitoring Study.The direct method was used to continuously monitor fan rotational speeds,and differential static pressures,coupled with periodic in-situ fan performance assessments,to calculate the VR.The indirect method consisted of estimating the VR using CO2 concentration measurements and the CO2 mass balance method.The average daily and hourly means(mean±SD)of directly measured barn ventilation rates for two years were(246±73)m3/s and(245±77)m3/s,respectively.The average daily and hourly means(mean±SD)of barn ventilation rates estimated by the CO2 mass balance method were(287±93.4)m3/s and(287±118)m3/s,respectively.Correlation analyses showed a strong correlation between the indirect CO2 mass balance method and direct measurement methods(r=0.93 for daily means and r=0.85 for hourly means). 展开更多
关键词 dynamic ventilation rate modern dairy free stall barn carbon dioxide mass balance dairy cow direct and indirect determination comparison
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DETERMINE评分在急性ST段抬高型心肌梗死患者预后中的预测价值
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作者 石子凡 刘泽岩 +3 位作者 徐凤 万俊 王仙岩 程景林 《医师在线》 2025年第9期55-58,共4页
目的探讨DETERMINE评分在急性ST段抬高型心肌梗死(STEMI)患者预后中的预测价值。方法选择2022年1月~2023年2月期间安徽医科大学第二附属医院收治的206例急性STEMI患者作为研究对象,根据病理性Q波、碎裂QRS波导联数及T波倒置导联数计算... 目的探讨DETERMINE评分在急性ST段抬高型心肌梗死(STEMI)患者预后中的预测价值。方法选择2022年1月~2023年2月期间安徽医科大学第二附属医院收治的206例急性STEMI患者作为研究对象,根据病理性Q波、碎裂QRS波导联数及T波倒置导联数计算通过心电图指标评估心肌梗死面积以确定除颤器植入风险评分(DETERMINE评分),并根据DETERMINE评分以近似四分位数分为四组,包括0~2分组(n=73)、3~5分组(n=36)、6~9分组(n=61)和≥10分组(n=36),比较各组间超声心电图指标、术后TIMI血流分级、罪犯血管及冠状动脉狭窄程度(SYNTAX积分)等差异,并根据随访1年的预后状况,即主要不良心血管事件(MACE)发生情况,采用多因素Logistic回归分析影响急性STEMI患者预后的相关因素。结果各组性别、年龄、BMI、基础疾病史、罪犯血管等基线资料比较,差异无统计学意义(P>0.05)。各组左心室舒张末期容积(LVEDV)比较,差异无统计学意义(P>0.05);0~2分组左心室舒张末期内径(LVEDd)显著低于6~9分组、≥10分组,差异有统计学意义(P<0.05);四组左心室射血分数(LVEF)比较,≥10分组<6~9分组<3~5分组<0~2分组,差异有统计学意义(P<0.05);各组术后TIMI血流分级比较,差异无统计学意义(P>0.05);四组SYNTAX积分比较,≥10分组>6~9分组>3~5分组>0~2分组,差异有统计学意义(P<0.05);多因素Logistic回归分析结果显示,DETERMINE评分和SYNTAX积分升高、LVEDd和LVEF降低是STEMI患者发生MACE的危险因素(OR=2.447、2.000、1.556、1.848,P<0.05)。结论DETERMINE评分用于预测急性STEMI患者的预后具有一定的临床应用价值,为判断急性STEMI患者预后提供一种简单且快速的风险评估工具。 展开更多
关键词 DETERMINE评分 ST段抬高型心肌梗死 主要不良心血管事件 预测价值
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Capillary electrophoresis as sample introduction system for highly sensitive and interference-free determination of ^(99)Tc by ICP-MS 被引量:2
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作者 Dan Zhou Liangjin Bao +6 位作者 Haoqi Long Duo Zhou Yuwei Xu Bo Wang Chuanqin Xia Liang Xian Chengbin Zheng 《Chinese Chemical Letters》 2025年第4期398-402,共5页
Although inductively coupled plasma mass spectrometry(ICP-MS) retains high sensitivity and has been intensively used for the measurement of ^(99)Tc, it usually suffers from tedious, expensive, and timeconsuming sample... Although inductively coupled plasma mass spectrometry(ICP-MS) retains high sensitivity and has been intensively used for the measurement of ^(99)Tc, it usually suffers from tedious, expensive, and timeconsuming sample pretreatments due to the isobaric interferences from ^(99)Ru and ^(98)Mo^(1)H. Herein, capillary electrophoresis(CE) was applied as sample introduction system for the sensitive, and interferencefree determination of ^(99)TcO_(4)^(-) from RuO_(4)^(-), and MoO_(4)^(2-) by ICP-MS with a simple sample treatment. Compared to the conventional methods, the hyphenated CE-ICP-MS avoids the use of expensive separation resins and reduces the consumption of mineral acid, representing a simpler, more efficient and environmentally benign approach. Moreover, the proposed method exhibits higher accuracy compared with the mathematical correction method using the natural isotope ratio of ^(99)Ru and ^(101)Ru, and significantly reduces sample consumption and the amount of waste, thus remarkably alleviating the radioactive exposure to operators and the pressure of radioactive waste treatment. Under the optimized conditions, the detection limits of 25 μg/L and 0.06 μg/L were obtained for RuO_(4)^(-) and ReO_(4)^(-)(Tc was replaced by Re), respectively, with relative standard deviation(RSD) lower than 5%. In addition, efficient recoveries of RuO_(4)^(-),ReO_(4)^(-),and ^(99)TcO_(4)^(-) from simulated Hanford site groundwater were achieved. The method is expected to be a promising candidate for sensitive and accurate analysis of ^(99)Tc from contaminated environmental samples. 展开更多
关键词 Radionuclide technetium-99 Capillary electrophoresis-inductively coupled plasma mass spectrometry(CE-ICP-MS) Rhenium(Re) Interference-free determination
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Simultaneous determination of peroxydisulfate and bisulfite concentrations with quenching-agent-assisted iodometry 被引量:1
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作者 Xinghong Wu Jun Deng +4 位作者 Jiawei Ye Pengyi Wang Xiangbin Huang Xin Yu Huabin Zeng 《Journal of Environmental Sciences》 2025年第8期153-162,共10页
Fenton/Fenton-like reactions have gained popularity for their remarkable proficiency in decomposing organic pollutants,especially when enhanced by reductants addition for accel-erating the Fe2+regeneration.Nevertheles... Fenton/Fenton-like reactions have gained popularity for their remarkable proficiency in decomposing organic pollutants,especially when enhanced by reductants addition for accel-erating the Fe2+regeneration.Nevertheless,these works predominantly centered on the formation and utilization of hydroxyl radicals(•OH)in the process,neglecting the evolution of oxidant and reductant due to the difficulty in the simultaneous determination of these two components.By employing the quenching-iodometric method,we could simultaneously determine the concentrations of HSO_(3)-and peroxydisulfate(PDS).This method first employed an excess of peroxymonosulfate(PMS)to effectively quench HSO_(3)-,and then used the iodometric spectrophotometry to simultaneously determine the concentrations of PMS and PDS in the reaction system.Finally,through precise stoichiometric relationships,we could accurately calculate the concentration of HSO_(3)-.Based on this method,we achieved concentration measurements that,upon linear fitting,yielded a correlation coefficient(R^(2))surpassing 0.99,unequivocally affirming the method’s accuracy and trustworthiness.In this work,an innovation approach for determining the concentrations of HSO_(3)-(reductant)and PDS(oxidant)was explored.Additionally,the resilience of the method was verified across different pH levels and in the presence of diverse impurity ions.The results ensured precise concentration measure-ments in the real wastewater.This method was characterized by its simplicity,rapid analysis,and environmental friendliness,offering a newanalytical strategy for the determination of PDS and HSO_(3)-in environmental samples.The method enables more meticulous monitoring of chemical usage in water treatment,facilitating optimized dosing strategies and assessments of reductant-enhanced Fenton or Fenton-like system in water purification. 展开更多
关键词 PDS BISULFITE PMS Simultaneous determination IODOMETRY
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