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Grain Yield,Biomass Accumulation,and Leaf Photosynthetic Characteristics of Rice under Combined Salinity-Drought Stress 被引量:1
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作者 WEI Huanhe GENG Xiaoyu +7 位作者 ZHANG Xiang ZHU Wang ZHANG Xubin CHEN Yinglong HUO Zhongyang ZHOU Guisheng MENG Tianyao DAI Qigen 《Rice science》 SCIE CSCD 2024年第1期118-128,I0023,共12页
Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinit... Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinity-drought stress poses a major threat to rice production.In this study,two salinity levels(NS,non-salinity;HS,high salinity)along with three drought treatments(CC,control condition;DJ,drought stress imposed at jointing;DH,drought stress imposed at heading)were performed to investigate their combined influences on leaf photosynthetic characteristics,biomass accumulation,and rice yield formation.Salinity,drought,and their combination led to a shortened growth period from heading to maturity,resulting in a reduced overall growth duration.Grain yield was reduced under both salinity and drought stress,with a more substantial reduction under the combined salinity-drought stress.The combined stress imposed at heading caused greater yield losses in rice compared with the stress imposed at jointing.Additionally,the combined salinity-drought stress induced greater decreases in shoot biomass accumulation from heading to maturity,as well as in shoot biomass and nonstructural carbohydrate(NSC)content in the stem at heading and maturity.However,it increased the harvest index and NSC remobilization reserve.Salinity and drought reduced the leaf area index and SPAD value of flag leaves and weakened the leaf photosynthetic characteristics as indicated by lower photosynthetic rates,transpiration rates,and stomatal conductance.These reductions were more pronounced under the combined stress.Salinity,drought,and especially their combination,decreased the activities of ascorbate peroxidase,catalase,and superoxide dismutase,while increasing the contents of malondialdehyde,hydrogen peroxide,and superoxide radical.Our results indicated a more significant yield loss in rice when subjected to combined salinity-drought stress.The individual and combined stresses of salinity and drought diminished antioxidant enzyme activities,inhibited leaf photosynthetic functions,accelerated leaf senescence,and subsequently lowered assimilate accumulation and grain yield. 展开更多
关键词 antioxidant defense system combined salinity-drought stress drought stress photosynthetic characteristics RICE salinity stress
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Detection of Turbulence Anomalies Using a Symbolic Classifier Algorithm in Airborne Quick Access Record(QAR)Data Analysis
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作者 Zibo ZHUANG Kunyun LIN +1 位作者 Hongying ZHANG Pak-Wai CHAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1438-1449,共12页
As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The ... As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The eddy dissipation rate(EDR)has been established as the standard metric for quantifying turbulence in civil aviation.This study aims to explore a universally applicable symbolic classification approach based on genetic programming to detect turbulence anomalies using quick access recorder(QAR)data.The detection of atmospheric turbulence is approached as an anomaly detection problem.Comparative evaluations demonstrate that this approach performs on par with direct EDR calculation methods in identifying turbulence events.Moreover,comparisons with alternative machine learning techniques indicate that the proposed technique is the optimal methodology currently available.In summary,the use of symbolic classification via genetic programming enables accurate turbulence detection from QAR data,comparable to that with established EDR approaches and surpassing that achieved with machine learning algorithms.This finding highlights the potential of integrating symbolic classifiers into turbulence monitoring systems to enhance civil aviation safety amidst rising environmental and operational hazards. 展开更多
关键词 turbulence detection symbolic classifier quick access recorder data
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Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system
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作者 Jing-Lei Huang Guo-Bin Jia +3 位作者 Li-Feng Han Wen-Qian Liu Li Huang Zheng-Han Yang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期222-233,共12页
A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the mol... A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power system.This model considers the impact of thermal properties of fluid variation on accuracy and has been validated with Simulink.This study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet parameters.Meanwhile,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also analyzed.The results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial values.This simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability. 展开更多
关键词 Molten salt reactor combined cycle Dynamic characteristic CONTROL
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Using Cross Entropy as a Performance Metric for Quantifying Uncertainty in DNN Image Classifiers: An Application to Classification of Lung Cancer on CT Images
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作者 Eri Matsuyama Masayuki Nishiki +1 位作者 Noriyuki Takahashi Haruyuki Watanabe 《Journal of Biomedical Science and Engineering》 2024年第1期1-12,共12页
Cross entropy is a measure in machine learning and deep learning that assesses the difference between predicted and actual probability distributions. In this study, we propose cross entropy as a performance evaluation... Cross entropy is a measure in machine learning and deep learning that assesses the difference between predicted and actual probability distributions. In this study, we propose cross entropy as a performance evaluation metric for image classifier models and apply it to the CT image classification of lung cancer. A convolutional neural network is employed as the deep neural network (DNN) image classifier, with the residual network (ResNet) 50 chosen as the DNN archi-tecture. The image data used comprise a lung CT image set. Two classification models are built from datasets with varying amounts of data, and lung cancer is categorized into four classes using 10-fold cross-validation. Furthermore, we employ t-distributed stochastic neighbor embedding to visually explain the data distribution after classification. Experimental results demonstrate that cross en-tropy is a highly useful metric for evaluating the reliability of image classifier models. It is noted that for a more comprehensive evaluation of model perfor-mance, combining with other evaluation metrics is considered essential. . 展开更多
关键词 Cross Entropy Performance Metrics DNN Image classifiers Lung Cancer Prediction Uncertainty
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Pressure stimulated current in progressive failure process of combined coal-rock under uniaxial compression:Response and mechanism
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作者 Tiancheng Shan Zhonghui Li +7 位作者 Xin Zhang Haishan Jia Xiaoran Wang Enyuan Wang Yue Niu Dong Chen Weichen Sun Dongming Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期227-243,共17页
Effective monitoring of the structural health of combined coal-rock under complex geological conditions by pressure stimulated currents(PSCs)has great potential for the understanding of dynamic disasters in undergroun... Effective monitoring of the structural health of combined coal-rock under complex geological conditions by pressure stimulated currents(PSCs)has great potential for the understanding of dynamic disasters in underground engineering.To reveal the effect of this way,the uniaxial compression experiments with PSC monitoring were conducted on three types of coal-rock combination samples with different strength combinations.The mechanism explanation of PSCs are investigated by resistivity test,atomic force microscopy(AFM)and computed tomography(CT)methods,and a PSC flow model based on progressive failure process is proposed.The influence of strength combinations on PSCs in the progressive failure process are emphasized.The results show the PSC responses between rock part,coal part and the two components are different,which are affected by multi-scale fracture characteristics and electrical properties.As the rock strength decreases,the progressive failure process changes obviously with the influence range of interface constraint effect decreasing,resulting in the different responses of PSC strength and direction in different parts to fracture behaviors.The PSC flow model is initially validated by the relationship between the accumulated charges of different parts.The results are expected to provide a new reference and method for mining design and roadway quality assessment. 展开更多
关键词 combined coal-rock Pressure stimulated current Progressive failure process MECHANISM Flow model
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RefluxClassifier分离细颗粒的技术发展与应用前景
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作者 马梦绮 张志远 +2 位作者 荆隆隆 方佳豪 李延锋 《有色金属(选矿部分)》 CAS 2024年第1期106-115,共10页
矿石综采技术带来诸多便利的同时,也导致了矿石中细颗粒比例增多。细颗粒分离成为了国内外矿物加工领域面临的难题。由于细颗粒质量小、比表面积大、表面能高、容易团聚,进而难以有效分离。本世纪初,由澳大利亚学者Galvin所研制的Reflux... 矿石综采技术带来诸多便利的同时,也导致了矿石中细颗粒比例增多。细颗粒分离成为了国内外矿物加工领域面临的难题。由于细颗粒质量小、比表面积大、表面能高、容易团聚,进而难以有效分离。本世纪初,由澳大利亚学者Galvin所研制的RefluxClassifier(回流分级机,简称RC)作为一种新型重力分选设备进入到矿物加工设备行列。该设备由液固流化床与倾斜通道组成,分为垂直段与倾斜段,具有操作简单、成本低廉和高效节能等优点。据研究,RC因其特殊的结构与工作机理可以有效解决细颗粒分离问题。本文首先归纳了国内外有关RC的理论研究,详细描述了RC倾斜段中颗粒在流体中的运动状态,阐明了倾斜通道内颗粒运动与流体流动特性之间的关系,简要分析了颗粒性质与流体之间的力与速度关系。此外,本文对目前现有RC的水速预测模型(经典动力学模型、经验模型、弱化粒度模型、平衡模型)进行了总结,并综合分析了各模型的适用范围。结合试验案例,介绍了RC在煤炭、黑金属、砂石骨料等领域的应用现状,举例分析不同试验条件下RC对细颗粒回收的分离情况。最后结合我国资源现状与现代设备发展趋势,提出如何深入优化RC分选理论模型、拓展更广阔的应用领域是国内外学者的长期研究目标,并展望RC在工业范围内的全面推广。 展开更多
关键词 Refluxclassifier 细粒回收 重力分选 颗粒运动
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CL2ES-KDBC:A Novel Covariance Embedded Selection Based on Kernel Distributed Bayes Classifier for Detection of Cyber-Attacks in IoT Systems
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作者 Talal Albalawi P.Ganeshkumar 《Computers, Materials & Continua》 SCIE EI 2024年第3期3511-3528,共18页
The Internet of Things(IoT)is a growing technology that allows the sharing of data with other devices across wireless networks.Specifically,IoT systems are vulnerable to cyberattacks due to its opennes The proposed wo... The Internet of Things(IoT)is a growing technology that allows the sharing of data with other devices across wireless networks.Specifically,IoT systems are vulnerable to cyberattacks due to its opennes The proposed work intends to implement a new security framework for detecting the most specific and harmful intrusions in IoT networks.In this framework,a Covariance Linear Learning Embedding Selection(CL2ES)methodology is used at first to extract the features highly associated with the IoT intrusions.Then,the Kernel Distributed Bayes Classifier(KDBC)is created to forecast attacks based on the probability distribution value precisely.In addition,a unique Mongolian Gazellas Optimization(MGO)algorithm is used to optimize the weight value for the learning of the classifier.The effectiveness of the proposed CL2ES-KDBC framework has been assessed using several IoT cyber-attack datasets,The obtained results are then compared with current classification methods regarding accuracy(97%),precision(96.5%),and other factors.Computational analysis of the CL2ES-KDBC system on IoT intrusion datasets is performed,which provides valuable insight into its performance,efficiency,and suitability for securing IoT networks. 展开更多
关键词 IoT security attack detection covariance linear learning embedding selection kernel distributed bayes classifier mongolian gazellas optimization
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Numerical Investigation of Combined Production of Natural Gas Hydrate and Conventional Gas
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作者 Hongzhi Xu Jian Wang +3 位作者 Shuxia Li Fengrui Zhao Chengwen Wang Yang Guo 《Fluid Dynamics & Materials Processing》 EI 2024年第3期505-523,共19页
Natural gas hydrate(NGH)is generally produced and accumulated together with the underlying conventional gas.Therefore,optimizing the production technology of these two gases should be seen as a relevant way to effecti... Natural gas hydrate(NGH)is generally produced and accumulated together with the underlying conventional gas.Therefore,optimizing the production technology of these two gases should be seen as a relevant way to effectively reduce the exploitation cost of the gas hydrate.In this study,three types of models accounting for the coexistence of these gases are considered.Type A considers the upper hydrate-bearing layer(HBL)adjacent to the lower conventional gas layer(CGL);with the Type B a permeable interlayer exists between the upper HBL and the lower CGL;with the type C there is an impermeable interlayer between the upper HBL and the lower CGL.The production performances associated with the above three models are calculated under different conditions,including only a depressurized HBL(only HBL DP);only a depressurized CGL(only CGL DP);and both the HBL and the CGL being depressurized(HBL+CGL DP).The results show that for Type A and Type B coexistence accumulation models,when only HBL or CGL is depressurized,the gas from the other layer will flow into the production layer due to the pressure difference between the two layers.In the coexistence accumulation model of type C,the cumulative gas production is much lower than that of Type A and Type B,regardless of whether only HBL DP,only CGL DP,or HBL+CGL DP are considered.This indicates that the impermeable interlayer restricts the cross-flow of gas between HBL and CGL.For three different coexistence accumulation models,CGL DP has the largest gas-to-water ratio. 展开更多
关键词 Natural gas hydrate conventional gas coexistence accumulation DEPRESSURIZATION combined production
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Anti-OX40 Antibody Combined with HBc VLPs Delays Tumor Growth in a Mouse Colon Cancer Model
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作者 LIU Jia Jia SU Qiu Dong +2 位作者 YI Yao SHEN Li Ping BI Sheng Li 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第2期187-195,共9页
Objective Combination immunotherapy strategies targeting OX40,a co-stimulatory molecule that can enhance antitumor immunity by modulating the proliferation,differentiation,and effector function of tumor-infiltrating T... Objective Combination immunotherapy strategies targeting OX40,a co-stimulatory molecule that can enhance antitumor immunity by modulating the proliferation,differentiation,and effector function of tumor-infiltrating T cells,have attracted much attention for their excellent therapeutic effects.In this study,we aimed to evaluate the antitumor efficacy of combined anti-OX40 and hepatitis B core viruslike particles(HBc VLPs)therapy using a mouse colon cancer model.Methods Humanized B-h OX40 mice were injected subcutaneously with MC38 colon tumor cells and treated with HBc VLPs+anti-h OX40 antibody.Tumor growth was monitored.Flow cytometric analysis was performed to evaluate the populations of T cell subsets in the tumors.Results The combination of anti-OX40 with HBc VLPs resulted in a significant delay in tumor growth,suggesting that a potent antitumor immunity was induced by the combination therapy.Further studies revealed that HBc VLPs+anti-OX40 treatment induced a significant increase in effector T cells(Teffs)and a significant decrease in regulatory T cells(Tregs)in the tumor microenvironment(TME),which accounted for the synergistic antitumor effect of anti-OX40 in combination with HBc VLPs.Conclusion Combination therapy of anti-h OX40 and HBc VLPs provides synergistic antitumor activity in colon cancer-bearing mice,which may represent a potential design strategy for cancer immunotherapy. 展开更多
关键词 Anti-OX40 antibody Hepatitis B core virus-like particles Tumor Combination therapy
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A Subdivision-Based Combined Shape and Topology Optimization in Acoustics
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作者 Chuang Lu Leilei Chen +1 位作者 Jinling Luo Haibo Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期847-872,共26页
We propose a combined shape and topology optimization approach in this research for 3D acoustics by using the isogeometric boundary element method with subdivision surfaces.The existing structural optimization methods... We propose a combined shape and topology optimization approach in this research for 3D acoustics by using the isogeometric boundary element method with subdivision surfaces.The existing structural optimization methods mainly contain shape and topology schemes,with the former changing the surface geometric profile of the structure and the latter changing thematerial distribution topology or hole topology of the structure.In the present acoustic performance optimization,the coordinates of the control points in the subdivision surfaces fine mesh are selected as the shape design parameters of the structure,the artificial density of the sound absorbing material covered on the structure surface is set as the topology design parameter,and the combined topology and shape optimization approach is established through the sound field analysis of the subdivision surfaces boundary element method as a bridge.The topology and shape sensitivities of the approach are calculated using the adjoint variable method,which ensures the efficiency of the optimization.The geometric jaggedness and material distribution discontinuities that appear in the optimization process are overcome to a certain degree by the multiresolution method and solid isotropic material with penalization.Numerical examples are given to validate the effectiveness of the presented optimization approach. 展开更多
关键词 Subdivision surfaces boundary element method topology optimization shape optimization combined optimization
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Lenvatinib combined with sintilimab plus transarterial chemoembolization as first-line treatment for advanced hepatocellular carcinoma
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作者 Sha-Sha Sun Xiao-Di Guo +1 位作者 Wen-Dong Li Jing-Long Chen 《World Journal of Clinical Cases》 SCIE 2024年第2期285-292,共8页
BACKGROUND Recently,combination therapy has shown a better trend towards improved tumour response and survival outcomes than monotherapy in patients with hepatocellular carcinoma(HCC).However,research on triple therap... BACKGROUND Recently,combination therapy has shown a better trend towards improved tumour response and survival outcomes than monotherapy in patients with hepatocellular carcinoma(HCC).However,research on triple therapy[lenvatinib+sintilimab+transarterial chemoembolization(TACE)]as a first-line treatment for advanced HCC is limited.AIM To evaluate the safety and efficacy of triple therapy as a first-line treatment for advanced HCC.METHODS HCC patients with Barcelona Clinic Liver Cancer stage C treated with triple therapy were enrolled.All patients were treated with lenvatinib every day and sintilimab once every 3 wk.Moreover,TACE was performed every 4-6 wk if necessary.The primary outcome of the study was overall survival(OS).The secondary outcomes were the objective response rate(ORR),disease control rate(DCR),and incidence of adverse events.RESULTS Forty HCC patients who underwent triple therapy were retrospectively analysed from January 2019 to January 2022.With a median follow-up of 8.5 months,the 3-,6-,and 12-mo OS rates were 100%,88.5%,and 22.5%,respectively.The ORR and DCR were 45%and 90%,respectively.The median progressive free survival and median OS were not reached.Common complications were observed in 76%of the patients(grade 3,15%;grade 4,2.5%).CONCLUSION Combination therapy comprising lenvatinib,sintilimab and TACE achieved promising outcomes in advanced HCC patients and had manageable effects. 展开更多
关键词 Lenvatinib Sintilimab Advanced hepatocellular carcinoma Combination therapy Tumor response
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Early Application Study of Intravenous Pain Pump Combined with Parecoxib Injection in Relieving Pain in Patients after Thoracoscopy
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作者 Heping Wu Linjuan Zeng 《Journal of Cancer Therapy》 2024年第4期212-218,共7页
Objective: To explore the clinical effectiveness of combined use of intravenous pain pump with Parecoxib injection in alleviating pain in patients during the early postoperative period after thoracoscopic surgery. Met... Objective: To explore the clinical effectiveness of combined use of intravenous pain pump with Parecoxib injection in alleviating pain in patients during the early postoperative period after thoracoscopic surgery. Methods: Eighty patients who underwent thoracoscopic surgery in a tertiary hospital were selected as the study subjects and randomly divided into two groups, with 40 patients in each group. The control group received routine postoperative treatment with intravenous pain pump, while the experimental group received Parecoxib in addition to the standard postoperative pain pump treatment. Visual Analog Scale (VAS) pain scores were used to evaluate postoperative pain relief in both groups, along with adverse reactions, postoperative complications, and patient satisfaction with pain relief. Results: Patients who received Parecoxib injection in addition to the routine use of intravenous pain pump had VAS pain scores lower than 3 points at 6 h, 12 h, 24 h, and 36 h postoperatively compared to those in the control group. The incidence of postoperative lung collapse, pleural effusion, and pulmonary infections was also significantly lower in the experimental group. The differences between the two groups were statistically significant (P Conclusion: Early combined use of Parecoxib injection in the early postoperative period after thoracoscopic surgery has shown good clinical efficacy. It can reduce the level of pain in patients, promote effective coughing and expectoration, facilitate early mobilization of patients, improve patient compliance, reduce complications, shorten hospital stay, and expedite patient recovery. Therefore, it is worth promoting the widespread clinical application of Parecoxib injection in this setting. 展开更多
关键词 PARECOXIB combined Use thoracoscopic Surgery Intravenous Pain Pump Postoperative Pain
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Targeted anti-tumor synergistic effects of Myc decoy oligodeoxynucleotides-loaded selenium nanostructure combined with chemoradiotherapy on LNCaP prostate cancer cells
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作者 ROGHAYEH GHORBANI MAHMOUD GHARBAVI +4 位作者 ALI SHARAFI ELHAM RISMANI HAMED REZAEEJAM YOUSEF MORTAZAVI BEHROOZ JOHARI 《Oncology Research》 SCIE 2024年第1期101-125,共25页
In the present study,we investigated the synergistic effects of targeted methotrexate-selenium nanostructure containing Myc decoy oligodeoxynucleotides along with X-irradiation exposure as a combination therapy on LNC... In the present study,we investigated the synergistic effects of targeted methotrexate-selenium nanostructure containing Myc decoy oligodeoxynucleotides along with X-irradiation exposure as a combination therapy on LNCaP prostate cancer cells.Myc decoy ODNs were designed based on the promoter of Bcl-2 gene and analyzed by molecular docking and molecular dynamics assays.ODNs were loaded on the synthesized Se@BSA@Chi-MTX nanostructure.The physicochemical characteristics of nanostructures were determined by FTIR,DLS,UV-vis,TEM,EDX,in vitro release,and hemolysis tests.Subsequently,the cytotoxicity properties of them with and without X-irradiation were investigated by uptake,MTT,cell cycle,apoptosis,and scratch assays on the LNCaP cell line.The results of DLS and TEM showed negative charge(−9 mV)and nanometer size(40 nm)for Se@BSA@Chi-DEC-MTX NPs,respectively.The results of FTIR,UV-vis,and EDX showed the proper interaction of different parts and the correct synthesis of nanoparticles.The results of hemolysis showed the hemocompatibility of this nanoparticle in concentrations less than 6 mg/mL.The ODNs release from the nanostructures showed a pH-dependent manner,and the release rate was 15%higher in acidic pH.The targeted Se@BSA@Chi-labeled ODN-MTX NPs were efficiently taken up by LNCaP cells by targeting the prostate-specific membrane antigen(PSMA).The significant synergistic effects of nanostructure(containing MTX drug)treatment along with X-irradiation showed cell growth inhibition,apoptosis induction(~57%),cell cycle arrest(G2/M phase),and migration inhibition(up to 90%)compared to the control.The results suggested that the Se@BSA@Chi-DEC-MTX NPs can potentially suppress the cell growth of LNCaP cells.This nanostructure system can be a promising approach for targeted drug delivery and chemoradiotherapy in prostate cancer treatment. 展开更多
关键词 CHEMORADIOTHERAPY Combination therapy Decoy oligodeoxynucleotides Myc transcription factor Selenium nanoparticle Prostate cancer
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A technique for enhancing tight oil recovery by multi-field reconstruction and combined displacement and imbibition
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作者 LEI Zhengdong WANG Zhengmao +6 位作者 MU Lijun PENG Huanhuan LI Xin BAI Xiaohu TAO Zhen LI Hongchang PENG Yingfeng 《Petroleum Exploration and Development》 SCIE 2024年第1期152-163,共12页
A seepage-geomechanical coupled embedded fracture flow model has been established for multi-field coupled simulation in tight oil reservoirs,revealing the patterns of change in pressure field,seepage field,and stress ... A seepage-geomechanical coupled embedded fracture flow model has been established for multi-field coupled simulation in tight oil reservoirs,revealing the patterns of change in pressure field,seepage field,and stress field after long-term water injection in tight oil reservoirs.Based on this,a technique for enhanced oil recovery(EOR)combining multi-field reconstruction and combination of displacement and imbibition in tight oil reservoirs has been proposed.The study shows that after long-term water flooding for tight oil development,the pressure diffusion range is limited,making it difficult to establish an effective displacement system.The variation in geostress exhibits diversity,with the change in horizontal minimum principal stress being greater than that in horizontal maximum principal stress,and the variation around the injection wells being more significant than that around the production wells.The deflection of geostress direction around injection wells is also large.The technology for EOR through multi-field reconstruction and combination of displacement and imbibition employs water injection wells converted to production and large-scale fracturing techniques to restructure the artificial fracture network system.Through a full lifecycle energy replenishment method of pre-fracturing energy supplementation,energy increase during fracturing,well soaking for energy storage,and combination of displacement and imbibition,it effectively addresses the issue of easy channeling of the injection medium and difficult energy replenishment after large-scale fracturing.By intensifying the imbibition effect through the coordination of multiple wells,it reconstructs the combined system of displacement and imbibition under a complex fracture network,transitioning from avoiding fractures to utilizing them,thereby improving microscopic sweep and oil displacement efficiencies.Field application in Block Yuan 284 of the Huaqing Oilfield in the Ordos Basin has demonstrated that this technology increases the recovery factor by 12 percentage points,enabling large scale and efficient development of tight oil. 展开更多
关键词 tight oil complex fracture network energy increase by fracturing multi-field reconstruction displacement and imbibition combination EOR
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Combined blasting for protection of gob-side roadway with thick and hard roof
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作者 Qiang Fu Jun Yang +4 位作者 Yubing Gao Changjiang Li Hongxu Song Yuxuan Liu Xing Wu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3165-3180,共16页
The deformation control of surrounding rock in gobside roadway with thick and hard roof poses a significant challenge to the safety and efficiency of coal mining.To address this issue,a novel approach combining direct... The deformation control of surrounding rock in gobside roadway with thick and hard roof poses a significant challenge to the safety and efficiency of coal mining.To address this issue,a novel approach combining directional and non-directional blasting techniques,known as combined blasting,was proposed.This study focuses on the experimental investigation of the proposed method in the 122108 working face in Caojiatan Coal Mine as the engineering background.The initial phase of the study involves physical model experiments to reveal the underlying mechanisms of combined blasting for protecting gob-side roadway with thick and hard roof.The results demonstrate that this approach effectively accelerates the collapse of thick and hard roofs,enhances the fragmentation and expansion coefficient of gangue,facilitates the filling of the goaf with gangue,and provides support to the overlying strata,thus reducing the subsidence of the overlying strata above the goaf.Additionally,the method involves cutting the main roof into shorter beams to decrease the stress and disrupt stress transmission pathways.Subsequent numerical simulations were conducted to corroborate the findings of the physical model experiments,thus validating the accuracy of the experimental results.Furthermore,field engineering experiments were performed,affirming the efficacy of the combined blasting method in mitigating the deformation of surrounding rock and achieving the desired protection of the gob-side roadway. 展开更多
关键词 Thick and hard roof Surrounding rock control combined blasting Fragmentation and expansion support stress relief
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Performance of Gas-Steam Combined Cycle Cogeneration Units Influenced by Heating Network Terminal Steam Parameters
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作者 Guanglu Xie Zhimin Xue +5 位作者 Bo Xiong Yaowen Huang Chaoming Chen Qing Liao Cheng Yang Xiaoqian Ma 《Energy Engineering》 EI 2024年第6期1495-1519,共25页
The determination of source-side extracted heating parameters is of great significance to the economic operation of cogeneration systems.This paper investigated the coupling performance of a cogeneration heating and p... The determination of source-side extracted heating parameters is of great significance to the economic operation of cogeneration systems.This paper investigated the coupling performance of a cogeneration heating and power system multidimensionally based on the operating characteristics of the cogeneration units,the hydraulic and thermodynamic characteristics of the heating network,and the energy loads.Taking a steam network supported by a gas-steam combined cycle cogeneration system as the research case,the interaction effect among the source-side prime movers,the heating networks,and the terminal demand thermal parameters were investigated based on the designed values,the plant testing data,and the validated simulation.The operating maps of the gas-steam combined cycle cogeneration units were obtained using THERMOFLEX,and the minimum source-side steam parameters of the steam network were solved using an inverse solution procedure based on the hydro-thermodynamic coupling model.The cogeneration operating maps indicate that the available operating domain considerably narrows with the rise of the extraction steam pressure and flow rate.The heating network inverse solution demonstrates that the source-side steam pressure and temperature can be optimized from the originally designed 1.11 MPa and 238.8°C to 1.074 MPa and 191.15°C,respectively.Under the operating strategy with the minimum source-side heating parameters,the power peak regulation depth remarkably increases to 18.30%whereas the comprehensive thermal efficiency decreases.The operation under the minimum source-side heating steam parameters can be superior to the originally designed one in the economy at a higher price of the heating steam.At a fuel price of$0.38/kg and the power to fuel price of 0.18 kg/(kW·h),the critical price ratio of heating steam to fuel is 119.1 kg/t.The influence of the power-fuel price ratio on the economic deviation appears relatively weak. 展开更多
关键词 Gas-steam combined cycle cogeneration of heating and power steam network inverse problem operating performance
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Mammogram Classification with HanmanNets Using Hanman Transform Classifier
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作者 Jyoti Dabass Madasu Hanmandlu +1 位作者 Rekha Vig Shantaram Vasikarla 《Journal of Modern Physics》 2024年第7期1045-1067,共23页
Breast cancer is a deadly disease and radiologists recommend mammography to detect it at the early stages. This paper presents two types of HanmanNets using the information set concept for the derivation of deep infor... Breast cancer is a deadly disease and radiologists recommend mammography to detect it at the early stages. This paper presents two types of HanmanNets using the information set concept for the derivation of deep information set features from ResNet by modifying its kernel functions to yield Type-1 HanmanNets and then AlexNet, GoogLeNet and VGG-16 by changing their feature maps to yield Type-2 HanmanNets. The two types of HanmanNets exploit the final feature maps of these architectures in the generation of deep information set features from mammograms for their classification using the Hanman Transform Classifier. In this work, the characteristics of the abnormality present in the mammograms are captured using the above network architectures that help derive the features of HanmanNets based on information set concept and their performance is compared via the classification accuracies. The highest accuracy of 100% is achieved for the multi-class classifications on the mini-MIAS database thus surpassing the results in the literature. Validation of the results is done by the expert radiologists to show their clinical relevance. 展开更多
关键词 MAMMOGRAMS ResNet 18 Hanman Transform classifier ABNORMALITY DIAGNOSIS VGG-16 AlexNet GoogleNet HanmanNets
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Roles of combined femoral and acetabular anteversion in pathological changes of hip dysplasia and hip reconstructive surgery
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作者 Can Liu Zheng Xu +5 位作者 Jian-Fa Zeng Zhen-Qi Song Yu-Yin Xie Zhong-Wen Tang Jie Wen Sheng Xiao 《World Journal of Orthopedics》 2024年第5期390-399,共10页
Combined femoral and acetabular anteversion is the sum of femoral and acetabular anteversion,representing their morphological relationship in the axial plane.Along with the increasing understanding of hip dysplasia in... Combined femoral and acetabular anteversion is the sum of femoral and acetabular anteversion,representing their morphological relationship in the axial plane.Along with the increasing understanding of hip dysplasia in recent years,numerous scholars have confirmed the role of combined femoral and acetabular anteversion in the pathological changes of hip dysplasia.At present,the reconstructive surgery for hip dysplasia includes total hip replacement and redirectional hip preservation surgery.As an important surgery index,combined femoral and acetabular anteversion have a crucial role in these surgeries.Herein,we discuss the role of combined femoral and acetabular anteversion in pathological changes of hip dysplasia,total hip replacement,and redirectional hip preservation surgery. 展开更多
关键词 combined anteversion Femoral anteversion Acetabular anteversion Hip dysplasia Hip preservation surgery Total hip replacement
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Combined hepatocellular cholangiocarcinoma: A clinicopathological update
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作者 Mukul Vij Fadl H Veerankutty +1 位作者 Ashwin Rammohan Mohamed Rela 《World Journal of Hepatology》 2024年第5期766-775,共10页
Combined hepatocellular-cholangiocarcinoma(cHCC-CCA)is a rare primary liver cancer associated with an appalling prognosis.The diagnosis and manage-ment of this entity have been challenging to physicians,radiologists,s... Combined hepatocellular-cholangiocarcinoma(cHCC-CCA)is a rare primary liver cancer associated with an appalling prognosis.The diagnosis and manage-ment of this entity have been challenging to physicians,radiologists,surgeons,pathologists,and oncologists alike.The diagnostic and prognostic value of biomarkers such as the immunohistochemical expression of nestin,a progenitor cell marker,have been explored recently.With a better understanding of biology and the clinical course of cHCC-CCA,newer treatment modalities like immune checkpoint inhibitors are being tried to improve the survival of patients with this rare disease.In this review,we give an account of the recent developments in the pathology,diagnostic approach,and management of cHCC-CCA. 展开更多
关键词 combined hepatocellular-cholangiocarcinoma Immunotherapy NESTIN Hepatocellular carcinoma CHOLANGIOCARCINOMA Liver cancer Biomarker Immune checkpoint inhibitors Pathology Genomic landscape
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Comprehensive Evaluation of Distributed PV Grid-Connected Based on Combined Weighting Weights and TOPSIS-RSR Method
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作者 Yue Yang Jiarui Zheng +2 位作者 Long Cheng Yongnan Zhu Hao Wu 《Energy Engineering》 EI 2024年第3期703-728,共26页
To effectively quantify the impact of distributed photovoltaic(PV)access on the distribution network,this paper proposes a comprehensive evaluation method of distributed PV grid connection combining subjective and obj... To effectively quantify the impact of distributed photovoltaic(PV)access on the distribution network,this paper proposes a comprehensive evaluation method of distributed PV grid connection combining subjective and objective combination of assignment and technique for order preference by similarity to an ideal solution(TOPSIS)—rank sum ratio(RSR)(TOPSIS-RSR)method.Based on the traditional distribution network evaluation system,a comprehensive evaluation system has been constructed.It fully considers the new development requirements of distributed PV access on the environmental friendliness and absorptive capacity of the distribution grid and comprehensively reflects the impact of distributed PV grid connection.The analytic hierarchy process(AHP)was used to determine the subjective weights of the primary indicators,and the Spearman consistency test was combined to determine the weights of the secondary indicators based on three objective assignment methods.The subjective and objective combination weights of each assessment indicator were calculated through the principle of minimum entropy.Calculate the distance between the indicators to be evaluated and the positive and negative ideal solutions,the relative closeness ranking,and qualitative binning by TOPSIS-RSR method to obtain the comprehensive evaluation results of different scenarios.By setting up different PV grid-connected scenarios and utilizing the IEEE33 node simulation algorithm,the correctness and effectiveness of the proposed subject-object combination assignment and integrated assessment method are verified. 展开更多
关键词 Distributed PV grid-connected comprehensive evaluation evaluation indicator system combined subjective and objective empowerment TOPSIS-RSR method
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