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Discovery and structure-activity relationship studies of novel tetrahydro-β-carboline derivatives as apoptosis initiators for treating bacterial infections
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作者 Shanshan Su Hongwu Liu +7 位作者 Junrong Zhang Puying Qi Yue Ding Ling Zhang Linli Yang Liwei Liu Xiang Zhou Song Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1259-1273,共15页
Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.In this paper,to discover the new bactericide candidates,we designed,prepared a... Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.In this paper,to discover the new bactericide candidates,we designed,prepared a new type of1,2,3,4-tetrahydro-β-carboline(THC)derivatives and evaluated the in vitro and in vivo bioactivities against the Xanthomonas oryzae pv.oryzae(Xoo),Xanthomonas axonopodis pv.citri(Xac),and Pseudomonas syringae pv.actinidiae(Psa).The in vitro bioassay results exhibited that most title molecules possessed good activity toward the three plant pathogenic bacteria,the compound A17 showed the most active against Xoo and Xac with EC50 values of 7.27 and 4.89 mg mL^(-1)respectively,and compound A8 exhibited the best inhibitory activity against Psa with EC50value of 4.87 mg mL^(-1).Pot experiments showed that compound A17 exhibited excellent in vivo antibacterial activities to manage rice bacterial leaf blight and citrus bacterial canker,with protective efficiencies of 52.67 and 79.79%at 200 mgmL^(-1),respectively.Meanwhile,compound A8 showed good control efficiency(84.31%)against kiwifruit bacterial canker at 200 mg mL^(-1).Antibacterial mechanism suggested that these compounds could interfere with the balance of the redox system,damage the cell membrane,and induce the apoptosis of Xoo cells.Taken together,our study revealed that tetrahydro-β-carboline derivatives could be a promising candidate model for novel broadspectrum bactericides. 展开更多
关键词 tetrahydro-β-carboline derivatives antibacterial activity ROS cell apoptosis
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Development and identification of two novel wheat-rye 6R derivative lines with adult-plant resistance to powdery mildew and high-yielding potential 被引量:1
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作者 Guohao Han Jing Wang +10 位作者 Hanwen Yan Tiantian Gu Lijun Cao Shiyu Liu Xiuquan Li Yilin Zhou Jieru Fan Zhipeng Shi Hong Liu Lihui Li Diaoguo An 《The Crop Journal》 SCIE CSCD 2024年第1期308-313,共6页
Powdery mildew,caused by Blumeria graminis f.sp.tritici(Bgt),is a devastating disease that seriously threatens wheat yield and quality.To control this disease,host resistance is the most effective measure.Compared wit... Powdery mildew,caused by Blumeria graminis f.sp.tritici(Bgt),is a devastating disease that seriously threatens wheat yield and quality.To control this disease,host resistance is the most effective measure.Compared with the resistance genes from common wheat,alien resistance genes can better withstand infection of this highly variable pathogen.Development of elite alien germplasm resources with powdery mildew resistance and other key breeding traits is an attractive strategy in wheat breeding.In this study,three wheat-rye germplasm lines YT4-1,YT4-2,and YT4-3 were developed through hybridization between octoploid triticale and common wheat,out of which the lines YT4-1 and YT4-2 conferred adult-plant resistance(APR)to powdery mildew while the line YT4-3 was susceptible to powdery mildew during all of its growth stages.Using genomic in situ hybridization,multi-color fluorescence in situ hybridization,multi-color GISH,and molecular marker analysis,YT4-1,YT4-2,and YT4-3 were shown to be cytogenetically stable wheat-rye 6R addition and T1RS.1BL translocation line,6RL ditelosomic addition and T1RS.1BL translocation line,and T1RS.1BL translocation line,respectively.Compared with previously reported wheat-rye derivative lines carrying chromosome 6R,YT4-1 and YT4-2 showed stable APR without undesirable pleiotropic effects on agronomic traits.Therefore,these novel wheat-rye 6R derivative lines are expected to be promising bridge resources in wheat disease breeding. 展开更多
关键词 Powdery mildew Secale cereale Triticum aestivum Wheat-rye 6R derivatives Agronomic performance
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Synthesis and evaluation of tetrahydro β-carboline derivatives as anticancer agents
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作者 刘洪瑞 鲍光植 +3 位作者 杨素娜 吴利新 古险峰 朱依谆 《Journal of Chinese Pharmaceutical Sciences》 CAS 2012年第5期416-420,共5页
A series of β-carboline derivatives (1–6) have been synthesized and evaluated for their anticancer activities. We observed that compound 5 exhibited significant anticancer activities over both human gastric cancer... A series of β-carboline derivatives (1–6) have been synthesized and evaluated for their anticancer activities. We observed that compound 5 exhibited significant anticancer activities over both human gastric cancer and human hepatic cancer cell lines, and compound 6, which is slightly different from 5 in its structure, showed good anticancer activity over human colorectal cancer cell line. 展开更多
关键词 INDOLE Tetrahydro β-carboline ANTICANCER
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Organic solar cells with D18 or derivatives offer efficiency over 19%
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作者 Erming Feng Chujun Zhang +3 位作者 Jianhui Chang Hengyue Li Liming Ding Junliang Yang 《Journal of Semiconductors》 EI CAS CSCD 2024年第5期1-4,共4页
In recent years,organic solar cells(OSCs)have garnered significant attention due to their distinctive attributes,such as flexibility,lightweight,and solution processing,which position them as alternatives for next-gen... In recent years,organic solar cells(OSCs)have garnered significant attention due to their distinctive attributes,such as flexibility,lightweight,and solution processing,which position them as alternatives for next-generation solar technologies[1−5].Thanks to breakthroughs in materials development,the power conversion efficiency(PCE)for single-junction OSCs has already surpassed 19%[6−13].The development of photoactive materials is pivotal in enhancing the PCEs,and several reviews have provided insights into materials design[14−18].Herein,we highlight single-junction OSCs based on D18 and its derivatives[19,20]. 展开更多
关键词 BREAKTHROUGH INSIGHT derivativeS
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Fullerenes and derivatives as electrocatalysts: Promises and challenges
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作者 Kun Guo Ning Li +1 位作者 Lipiao Bao Xing Lu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期7-27,共21页
Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion technologies.Of paramount significance are the establishment of design princi... Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion technologies.Of paramount significance are the establishment of design principles by understanding the catalytic mechanisms and identifying the active sites.Distinct from sp2-conjugated graphene and carbon nanotube,fullerene possesses unique characteristics that are growingly being discovered and exploited by the electrocatalysis community.For instance,the well-defined atomic and molecular structures,the good electron affinity to tune the electronic structures of other substances,the intermolecular self-assembly into superlattices,and the on-demand chemical modification have endowed fullerene with incomparable advantages as electrocatalysts that are otherwise not applicable to other carbon ma-terials.As increasing studies are being reported on this intriguing topic,it is necessary to provide a state-of-the-art overview of the recent progress.This review takes such an initiative by summarizing the promises and challenges in the electrocatalytic applications of fullerene and its derivatives.The content is structured according to the composition and structure of fullerene,including intact fullerene(e.g.,fullerene composite and superlattices)and fullerene derivatives(e.g.,doped,endohedral,and disintegrated fullerene).The synthesis,characterization,catalytic mechanisms,and deficiencies of these fullerene-based materials are explicitly elaborated.We conclude it by sharing our perspectives on the key aspects that future efforts shall consider. 展开更多
关键词 FULLERENE Fullerene derivative Metal-free catalyst Structural defect ELECTROCATALYST
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Photoinduced Room-Temperature Phosphorescence of Triphenylamine-Phenothiazine Derivative-Doped Polymers
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作者 Li Nan Wang Yunsheng Li Zhen 《有机化学》 SCIE CAS CSCD 北大核心 2024年第8期2487-2494,共8页
Photo-responsive room-temperature phosphorescent(RTP)materials have garnered significant interest due to the advantages of rapid response,spatiotemporal control,and contactless precision manipulation.However,the devel... Photo-responsive room-temperature phosphorescent(RTP)materials have garnered significant interest due to the advantages of rapid response,spatiotemporal control,and contactless precision manipulation.However,the development of such materials remains in its infancy,underscoring the importance of exploiting novel and efficient light-responsive RTP molecules.In this work,three phenothiazine derivatives of TPA-PTZ,TPA-2PTZ,and TPA-3PTZ were successfully synthesized via the Buchwald-Hartwig C—N coupling reaction.By embedding these molecules as RTP guests into polymethyl methacrylate(PMMA)matrix,photo-induced RTP properties were realized.Upon sustained UV irradiation,there was an enhancement of 19 times in the quantum yield to reach a value of 5.68%.Remarkably,these materials exhibit superior alongside robust light and thermal stability,maintaining high phosphorescence intensity even after prolonged UV exposure(irradiation for>200 s by a 365 nm UV lamp with the power of 500μW·cm-2)or at higher temperature up to 75℃.The outstanding properties of these photo-induced RTP materials make them promising candidates for applications in information encryption,anti-counterfeiting,and advanced optical materials. 展开更多
关键词 stimuli-responsive luminescent materials photo-induced room-temperature phosphorescence phenothiazine derivatives doped polymer
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High-Value-Added Utilization of Turpentine:Screening of Anti-Influenza Virus Agents fromβ-Pinene Derivatives
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作者 Yiwen Li Hongyan Si +7 位作者 Peng Wang Hai Luo Minggui Shen Xiaoping Rao Zhanqian Song Shibin Shang Zongde Wang Shengliang Liao 《Journal of Renewable Materials》 EI CAS 2024年第1期45-56,共12页
Turpentine is a renewable and resourceful forest product.The deep processing and utilization of turpentine,particularly its primary componentβ-pinene,has garnered widespread attention.This study aimed to synthesize 4... Turpentine is a renewable and resourceful forest product.The deep processing and utilization of turpentine,particularly its primary componentβ-pinene,has garnered widespread attention.This study aimed to synthesize 40 derivatives ofβ-pinene,including nopinone,3-cyanopyridines of nopinone,myrtanyl acid,myrtanyl acylthioureas,and myrtanyl amides.We assessed the antiviral activities of theseβ-pinene derivatives against influenza virus A/Puerto Rico/8/34(H1N1)using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method.Theβ-pinene derivatives were used before and after cellular infection with the influenza virus to evaluate their preventive and therapeutic effects against the H1N1 virus.The results showed that only compound 10o exhibited a preventive effect against the H1N1 virus with a half-maximal inhibitory concentration(IC50)value of 47.6μmol/L.Among the compounds,4e,4i,and 4l demonstrated therapeutic effects against cellular infection,with compound 4e displaying the most potent therapeutic effect(IC50=17.5μmol/L),comparable to the positive control ribavirin.These findings indicated that certainβ-pinene derivatives exhibited in vitro antiviral activity against the H1N1 influenza A virus,warranting further investigation as potential anti-influenza agents. 展开更多
关键词 Antiviral activity Β-PINENE derivative 3-CYANOPYRIDINE influenza virus
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Solution approximations for a mathematical model of relativistic electrons with beta derivative
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作者 Ibrahim Yalcinkaya Orkun Tasbozan +1 位作者 Ali Kurt Hijaz Ahmad 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期469-485,共17页
The main aim of this paper is to obtain the exact and semi-analytical solutions of the nonlinear Klein-Fock-Gordon(KFG)equation which is a model of relativistic electrons arising in the laser thermonuclear fusion with... The main aim of this paper is to obtain the exact and semi-analytical solutions of the nonlinear Klein-Fock-Gordon(KFG)equation which is a model of relativistic electrons arising in the laser thermonuclear fusion with beta derivative.For this purpose,both the modified extended tanh-function(mETF)method and the homotopy analysis method(HAM)are used.While applying the mETF the chain rule for beta derivative and complex wave transform are used for obtaining the exact solution.The advantage of this procedure is that discretization or normalization is not required.By applying the mETF,the exact solutions are obtained.Also,by applying the HAM semi-analytical results for the considered equation are acquired.In HAM?curve gives us a chance to find the suitable value of the for the convergence of the solution series.Also,comparative graphical representations are given to show the effectiveness,reliability of the methods.The results show that the m ETF and HAM are reliable and applicable tools for obtaining the solutions of non-linear fractional partial differential equations that involve beta derivative.This study can bring a new perspective for studies on fractional differential equations.On the other hand,it can be said that scientists can apply the considered methods for different mathematical models arising in physics,chemistry,engineering,social sciences and etc.which involves fractional differentiation.Briefly the results may cause a new insight who studies on relativistic electron modelling. 展开更多
关键词 Klein-Fock-Gordon(KFG)equation beta derivative semi-analytical solution exact solution
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Identification of key genes regulating the synthesis of quercetin derivatives in Rosa roxburghii through integrated transcriptomics and metabolomics
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作者 Liyao Su Min Wu +2 位作者 Tian Zhang Yan Zhong Zongming(Max) Cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期876-887,共12页
Rosa roxburghii fruit is rich in flavonoids, but little is known about their biosynthetic pathways. In this study, we employed transcriptomics and metabolomics to study changes related to the flavonoids at five differ... Rosa roxburghii fruit is rich in flavonoids, but little is known about their biosynthetic pathways. In this study, we employed transcriptomics and metabolomics to study changes related to the flavonoids at five different stages of R. roxburghii fruit development. Flavonoids and the genes related to their biosynthesis were found to undergo significant changes in abundance across different developmental stages, and numerous quercetin derivatives were identified. We found three gene expression modules that were significantly associated with the abundances of the different flavonoids in R. roxburghii and identified three structural UDP-glycosyltransferase genes directly involved in the synthesis of quercetin derivatives within these modules. In addition, we found that RrBEH4, RrLBD1 and RrPIF8could significantly increase the expression of downstream quercetin derivative biosynthesis genes. Taken together,these results provide new insights into the metabolism of flavonoids and the accumulation of quercetin derivatives in R. roxburghii. 展开更多
关键词 Rosa roxburghii quercetin derivatives weighted gene co-expression network analysis transcription factor transcriptome METABOLOME
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Tailored multifunctional hydrazine derivatives for efficient printable hole-conductive-free mesoscopic perovskite solar cells via enhancing defect passivation
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作者 Minghao Xia Ziwei Zheng +6 位作者 Yanjie Cheng Chaoyang Wang Zhaozhen Cui Guodong Zhang Jinwei Gonga Anyi Mei Hongwei Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期357-363,I0008,共8页
The low-cost and easy large-scale fabrication advantages of printable mesoscopic perovskite solar cells(p-MPSCs)are overshadowed by their limited photovoltaic conversion efficiency(PCE).Here,we introduce the hydrazide... The low-cost and easy large-scale fabrication advantages of printable mesoscopic perovskite solar cells(p-MPSCs)are overshadowed by their limited photovoltaic conversion efficiency(PCE).Here,we introduce the hydrazide derivative of 4-Hydroxybenzoylhydrazine(4-HBH)to improve the PCE of p-MPSCs by inducing enhanced defect passivation.Both carbonyl and hydrazine groups in hydrazide groups present strong interaction with perovskite.The hydroxyl group,as an electron donor group,increases the electron cloud density of the hydrazide group in 4-HBH under the conjugation of the benzene ring,and thus enhances its interaction with perovskite.Additionally,the hydroxy group itself interacts with perovskite and passivates defects synergistically.The hydrazine agents can also reduce I2and suppress the loss of iodine in perovskite films,which inhibits the formation of iodine-related defects.Consequently,p-MPSCs with 4-HBH achieve a high PCE of 19.21%,and present well improved stability. 展开更多
关键词 Printable mesoscopic perovskite solar cells Multifunctional hydrazine derivatives Cooperative coordination Conjugation redox activity
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Preparation of kakkatin derivatives and their anti-tumor activity
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作者 Yu-Ying Jiang Hui-Hua Dong +3 位作者 Wen-Ting Zhou Jia-Zi Luo Xian Wei Yan-Qiang Huang 《World Journal of Clinical Oncology》 2024年第8期1078-1091,共14页
BACKGROUND Modern pharmacological studies have confirmed that plant-derived compounds from Puerariae flos(PF)has significant biological activities against liver damage,tumors and inflammation.Kakkatin is an isoflavone... BACKGROUND Modern pharmacological studies have confirmed that plant-derived compounds from Puerariae flos(PF)has significant biological activities against liver damage,tumors and inflammation.Kakkatin is an isoflavone polyphenolic compound isolated from PF flower.However,the effect of kakkatin and its derivatives on anti-tumor has not been well explored.AIM To design and synthesize a kakkatin derivative[6-(hept-6-yn-1-yloxy)-3-(4-hydroxyphenyl)-7-methoxy-4H-chromen-4-one(HK)]to explore its anti-tumor biological activity.METHODS Hept-6-yn-1-yl ethanesulfonate was introduced to replace hydrogen at the hydroxyl position of kakkatin phenol,and the derivative of kakkatin was prepared;the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide was used to detect cell viability,a clone formation assay was adopted to detect cell proliferation,apoptosis,necrosis,and cell cycles were analyzed by Annexin V/propidium iodide staining and flow cytometry.Cell migration and invasion ability were evaluated by cell scratch assay and transwell assay.The potential mechanism of HK on hepatocellular carcinoma(HCC)SMMC-7721 cells was explored through network pharmacology and molecular docking,and finally real-time PCR assays was used to verify the potential targets and evaluate the biological activity of HK.RESULTS Compared with kakkatin,the modified HK did not significantly increase the inhibitory activity of gastric cancer MGC803 cells,but the inhibitory activity of HCC SMMC-7721 cells was increased by about 30 times,with an IC50 value of 2.5μM,and the tumor inhibition effect was better than cisplatin,which could significantly inhibit the cloning,invasion and metastasis of HCC SMMC-7721 cells,and induce apoptosis and G2/M cycle arrest.Its mechanism of action is mainly related to the upregulation of PDE3B and NFKB1 target proteins in the cAMP pathway.CONCLUSION HK have a significant inhibitory effect on HCC SMMC-7721 cells,and the targets of their action may be PDE3B and NFKB1 proteins in the cAMP pathway,making it a good lead drug for the treatment of HCC. 展开更多
关键词 Kakkatin derivative Hepatocellular carcinoma ANTI-TUMOR Biological activity
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Study on Antitumor Activity of Piperidine Derivatives
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作者 Zhenwei NIE Hongxia LI +2 位作者 Weizhen LI Hangyu MENG Wei XU 《Agricultural Biotechnology》 2024年第3期81-85,89,共6页
[Objectives]This study was conducted to investigate the effects of piperidine derivatives on the proliferation and apoptosis of tumor cells(Hele).[Methods]The target end product(piperidine derivative)was synthesized t... [Objectives]This study was conducted to investigate the effects of piperidine derivatives on the proliferation and apoptosis of tumor cells(Hele).[Methods]The target end product(piperidine derivative)was synthesized through a series of organic reactions.The MTT assay was adopted to detect the effect of piperidine derivative on the proliferation activity of Hele cells.The ROS fluorescence probe method was used to detect the changes of reactive oxygen species.The JC-1 method was applied to detect the changes of MMP in Hele cells.Flow cytometry was adopted to detect the apoptosis of Hele cells.[Results]The cell survival rates were 70.84%,65.46%and 54.48%when the drug concentration was 100,110 and 120μmol/L,respectively.When the drug concentration increased to 120μmol/L,the cell survival rate decreased by nearly half.The fluorescence intensity of active oxygen in the control group was 1,and when the drug concentrations were 100,110 and 120μmol/L,the fluorescence intensity of active oxygen was,respectively,1.315,1.478 and 1.677,which were higher than that in the control group.The red/green fluorescence intensity of the MMP control group was 1.819,and that of drug groups was,respectively,1.643,1.164 and 0.665,which were lower than that of the control group.The apoptosis rates were 10.79%,22.91%and 38.54%at the drug concentrations of 100,110 and 120μmol/L,respectively,showing a concentration dependent effect.The results showed that the piperidine derivative could inhibit the proliferation of Hele cells and induce apoptosis,which was positively correlated with the concentration.[Conclusions]This study provides theoretical basis and reference for the anti-tumor research of piperidine. 展开更多
关键词 Piperidine derivative Hele cell Anti-cancer activity
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Laboratory Implementation of Direct Torque Controller based Speed Loop Pseudo Derivative Feedforward Controller for PMSM Drive
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作者 Prabhakaran Koothu Kesavan Umashankar Subramaniam Dhafer J.Almakhles 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期12-21,共10页
This paper,evaluate the effectiveness of a proposed speed loop pseudo derivative feedforward(PDFF)controller-based direct torque controller(DTC)for a PMSM drive against the performance of existing PI speed controller-... This paper,evaluate the effectiveness of a proposed speed loop pseudo derivative feedforward(PDFF)controller-based direct torque controller(DTC)for a PMSM drive against the performance of existing PI speed controller-based DTC and hysteresis current controller(HCC).The proposed PDFF-based speed regulator effectively reduces oscillation and overshoot associated with rotor angular speed,electromagnetic torque,and stator current.Two case studies,one using forward-to-reverse motoring operation and the other involving reverse-to-forward braking operation,has been validated to show the effectiveness of the proposed control strategy.The proposed controller's superior performance is demonstrated through experimental verification utilizing an FPGA controller for a 1.5 kW PMSM drive laboratory prototype. 展开更多
关键词 Direct torque control Pseudo derivative feedforward controller Permanent magnet synchronous motor(PMSM)
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Sepsis Prediction Using CNNBDLSTM and Temporal Derivatives Feature Extraction in the IoT Medical Environment
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作者 Sapiah Sakri Shakila Basheer +4 位作者 Zuhaira Muhammad Zain Nurul Halimatul Asmak Ismail Dua’Abdellatef Nassar Manal Abdullah Alohali Mais Ayman Alharaki 《Computers, Materials & Continua》 SCIE EI 2024年第4期1157-1185,共29页
Background:Sepsis,a potentially fatal inflammatory disease triggered by infection,carries significant healthimplications worldwide.Timely detection is crucial as sepsis can rapidly escalate if left undetected.Recentad... Background:Sepsis,a potentially fatal inflammatory disease triggered by infection,carries significant healthimplications worldwide.Timely detection is crucial as sepsis can rapidly escalate if left undetected.Recentadvancements in deep learning(DL)offer powerful tools to address this challenge.Aim:Thus,this study proposeda hybrid CNNBDLSTM,a combination of a convolutional neural network(CNN)with a bi-directional long shorttermmemory(BDLSTM)model to predict sepsis onset.Implementing the proposed model provides a robustframework that capitalizes on the complementary strengths of both architectures,resulting in more accurate andtimelier predictions.Method:The sepsis prediction method proposed here utilizes temporal feature extraction todelineate six distinct time frames before the onset of sepsis.These time frames adhere to the sepsis-3 standardrequirement,which incorporates 12-h observation windows preceding sepsis onset.All models were trained usingthe Medical Information Mart for Intensive Care III(MIMIC-III)dataset,which sourced 61,522 patients with 40clinical variables obtained from the IoT medical environment.The confusion matrix,the area under the receiveroperating characteristic curve(AUCROC)curve,the accuracy,the precision,the F1-score,and the recall weredeployed to evaluate themodels.Result:The CNNBDLSTMmodel demonstrated superior performance comparedto the benchmark and other models,achieving an AUCROC of 99.74%and an accuracy of 99.15%one hour beforesepsis onset.These results indicate that the CNNBDLSTM model is highly effective in predicting sepsis onset,particularly within a close proximity of one hour.Implication:The results could assist practitioners in increasingthe potential survival of the patient one hour before sepsis onset. 展开更多
关键词 Temporal derivatives hybrid deep learning predicting sepsis onset MIMIC III machine learning(ML) deep learning
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Numerical Treatments for Crossover Cancer Model of Hybrid Variable-Order Fractional Derivatives
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作者 Nasser Sweilam Seham Al-Mekhlafi +2 位作者 Aya Ahmed Ahoud Alsheri Emad Abo-Eldahab 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1619-1645,共27页
In this paper,two crossover hybrid variable-order derivatives of the cancer model are developed.Grünwald-Letnikov approximation is used to approximate the hybrid fractional and variable-order fractional operators... In this paper,two crossover hybrid variable-order derivatives of the cancer model are developed.Grünwald-Letnikov approximation is used to approximate the hybrid fractional and variable-order fractional operators.The existence,uniqueness,and stability of the proposed model are discussed.Adams Bashfourth’s fifth-step method with a hybrid variable-order fractional operator is developed to study the proposed models.Comparative studies with generalized fifth-order Runge-Kutta method are given.Numerical examples and comparative studies to verify the applicability of the used methods and to demonstrate the simplicity of these approximations are presented.We have showcased the efficiency of the proposed method and garnered robust empirical support for our theoretical findings. 展开更多
关键词 Cancer diseases hybrid variable-order fractional derivatives adams bashfourth fifth step generalized fifth order Runge-Kutta method
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Avoiding the Use of Lagrange Multipliers. II. Constrained Extrema of Functionals and the Evaluation of Constrained Derivatives
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作者 David S. Corti Ricardo Fariello 《Journal of Applied Mathematics and Physics》 2024年第8期2764-2788,共25页
A method for determining the extrema of a real-valued and differentiable function for which its dependent variables are subject to constraints and that avoided the use of Lagrange multipliers was previously presented ... A method for determining the extrema of a real-valued and differentiable function for which its dependent variables are subject to constraints and that avoided the use of Lagrange multipliers was previously presented (Corti and Fariello, Op. Res. Forum 2 (2021) 59). The method made use of projection matrices, and a corresponding Gram-Schmidt orthogonalization process, to identify the constrained extrema. Furthermore, information about the second-derivatives of the given function with constraints was generated, from which the nature of the constrained extrema could be determined, again without knowledge of the Lagrange multipliers. Here, the method is extended to the case of functional derivatives with constraints. In addition, constrained first-order and second-order derivatives of the function are generated, in which the derivatives with respect to a given variable are obtained and, concomitantly, the effect of the variations of the remaining chosen set of dependent variables are strictly accounted for. These constrained derivatives are valid not only at the extrema points, and also provide another equivalent route for the determination of the constrained extrema and their nature. 展开更多
关键词 Constrained Extrema Functional derivatives Projection Matrices
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Design and synthesis of 1-substituted-β-carboline derivatives as potential anticancer agents 被引量:1
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作者 郭亮 范文玺 +3 位作者 甘紫云 陈伟 马芹 曹日晖 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第12期801-808,共8页
In the present study, we designed and synthesized a series of 1-substituted-β-carboline derivatives through modification of position-l, 2 and 9 of β-carboline nucleus in order to discover novel leading compounds wit... In the present study, we designed and synthesized a series of 1-substituted-β-carboline derivatives through modification of position-l, 2 and 9 of β-carboline nucleus in order to discover novel leading compounds with better antitumor activities and less toxicity. Their structures were confirmed by 1H NMR, 13C NMR, MS, IR and elemental analyses. All the target compounds were tested for cytotoxic activity against six cancer cell lines, including Bel-7402, HepG2, A549, A375, 786-0 and HT-29 by methyl thiazolyl tetrazolium (MTT) method. Studies of structure-activity relationships indicated that the effects of substituents in position- 1 on cytotoxic activities were in an order as follows: 2-thienyl 〉2-chlorophenyl 〉4-chlorophenyl 〉benzyl group. 展开更多
关键词 β-carboline SYNTHESIS Anticancer activity Structure-activity relationships
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Applications of Metal–Organic Frameworks and Their Derivatives in Electrochemical CO_(2)Reduction 被引量:6
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作者 Chengbo Li Yuan Ji +8 位作者 Youpeng Wang Chunxiao Liu Zhaoyang Chen Jialin Tang Yawei Hong Xu Li Tingting Zheng Qiu Jiang Chuan Xia 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第8期72-115,共44页
Electrochemically reducing CO_(2)to more reduced chemical species is a promising way that not only enables the conversion of intermittent energy resources to stable fuels,but also helps to build a closed-loop anthropo... Electrochemically reducing CO_(2)to more reduced chemical species is a promising way that not only enables the conversion of intermittent energy resources to stable fuels,but also helps to build a closed-loop anthropogenic carbon cycle.Among various electrocatalysts for electrochemical CO_(2)reduction,multifunctional metal–organic frameworks(MOFs)have been employed as highly efficient and selective heterogeneous electrocatalysts due to their ultrahigh porosity and topologically diverse structures.Up to now,great progress has been achieved in the design and synthesis of highly active and selective MOF-related catalysts for electrochemical CO_(2)reduction reaction(CO_(2)RR),and their corresponding reaction mechanisms have been thoroughly studied.In this review,we summarize the recent progress of applying MOFs and their derivatives in CO_(2)RR,with a focus on the design strategies for electrocatalysts and electrolyzers.We first discussed the reaction mechanisms for different CO_(2)RR products and introduced the commonly applied electrolyzer configurations in the current CO_(2)RR system.Then,an overview of several categories of products(CO,HCOOH,CH_(4),CH_(3)OH,and multi-carbon chemicals)generated from MOFs or their derivatives via CO_(2)RR was discussed.Finally,we offer some insights and perspectives for the future development of MOFs and their derivatives in electrochemical CO_(2)reduction.We aim to provide new insights into this field and further guide future research for large-scale applications. 展开更多
关键词 Metal-organic frameworks derivativeS CATALYST CO_(2)reduction reaction ELECTROCATALYSIS
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Advances and challenges in using nirmatrelvir and its derivatives against SARS-CoV-2 infection 被引量:2
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作者 Wujun Chen Bing Liang +3 位作者 Xiaolin Wu Ling Li Chao Wang Dongming Xing 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第3期255-261,共7页
On December 22,2021,the United States Food and Drug Administration approved the first main protease inhibitor,i.e.,oral antiviral nirmatrelvir(PF-07321332)/ritonavir(Paxlovid),for the treatment of early severe acute r... On December 22,2021,the United States Food and Drug Administration approved the first main protease inhibitor,i.e.,oral antiviral nirmatrelvir(PF-07321332)/ritonavir(Paxlovid),for the treatment of early severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection.Nirmatrelvir inhibits SARSCoV-2 infection,but high doses or long-term treatment may cause embryonic developmental toxicity and changes in host gene expression.The chiral structure of nirmatrelvir plays a key role in its antiviral activity.Ritonavir boosts the efficacy of nirmatrelvir by inactivating cytochrome P4503A4 expression and occupying the plasma protein binding sites.Multidrug resistance protein 1 inhibitors may increase the efficacy of nirmatrelvir.However,Paxlovid has many contraindications.Some patients treated with Paxlovid experience a second round of coronavirus disease 2019(COVID-19)symptoms soon after recovery.Interestingly,the antiviral activity of nirmatrelvir metabolites,such as compounds 12e18,is similar to or higher than that of nirmatrelvir.Herein,we review the advances and challenges in using nirmatrelvir and its derivatives with the aim of providing knowledge for drug developers and physicians in the fight against COVID-19. 展开更多
关键词 Nirmatrelvir PHARMACOLOGY PHARMACOKINETICS TOXICOLOGY derivativeS COVID-19
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Study of Fractional Order Dynamical System of Viral Infection Disease under Piecewise Derivative 被引量:2
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作者 Kamal Shah Hafsa Naz +1 位作者 Thabet Abdeljawad Bahaaeldin Abdalla 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期921-941,共21页
This research aims to understand the fractional order dynamics of the deadly Nipah virus(NiV)disease.We focus on using piecewise derivatives in the context of classical and singular kernels of power operators in the C... This research aims to understand the fractional order dynamics of the deadly Nipah virus(NiV)disease.We focus on using piecewise derivatives in the context of classical and singular kernels of power operators in the Caputo sense to investigate the crossover behavior of the considered dynamical system.We establish some qualitative results about the existence and uniqueness of the solution to the proposed problem.By utilizing the Newtonian polynomials interpolation technique,we recall a powerful algorithm to interpret the numerical findings for the aforesaid model.Here,we remark that the said viral infection is caused by an RNA type virus which can transmit from animals and also from an infected person to person.Fruits bats which are also known as flying foxes are one of the sources of transmission of NiV disease.Here in this work,we investigate its transmission mechanism through some new concepts of fractional calculus for further analysis and prediction.We present the approximate results for different compartments using different fractional orders.By using the piecewise derivative concept,we detect the crossover ormulti-steps behavior in the transmission dynamics of the mentioned disease.Therefore,the considered form of the derivative is used to deal with problems exhibiting crossover behaviors. 展开更多
关键词 NiV disease fractional calculus piecewise derivative qualitative results newton polynomial RNA virus
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