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Role of exosomal circular RNAs as microRNA sponges and potential targeting for suppressing hepatocellular carcinoma growth and progression
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作者 Nikolaos Papadopoulos Eleni-Myrto Trifylli 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期994-998,共5页
In this editorial,we comment on the article by Lyu et al published in the recent issue of the World Journal of Gastroenterology(2023;2219-2840).Hepatocellular carcinoma(HCC)is a frequently encountered and highly aggre... In this editorial,we comment on the article by Lyu et al published in the recent issue of the World Journal of Gastroenterology(2023;2219-2840).Hepatocellular carcinoma(HCC)is a frequently encountered and highly aggressive primary liver cancer,which remains the third-commonest cause of cancer-related death despite the current therapeutic modalities.There is urgency in developing novel thera-peutic approaches,such as by manipulating extracellular vesicles,which con-stitute a highly heterogeneous nanoparticle population that contains various cargoes.These cargoes have a pivotal role in cell-to-cell communication and can modify the functional level of the recipient cells via their uptake by other recipient cells.Exosomal non-coding RNAs have particular evolving significance in HCC,such as circular RNAs,which have been found differentially expressed in normal hepatic and HCC tissues.The aberrations in their expression levels have a key role in the HCC development and progression and the overall prognosis.In this editorial,we will shed light on the emerging role of exosomal circular RNAs in HCC development and progression,focusing on the oncogenic or potentially tumor suppressive effect of mesenchymal stem cells-derived exosomal non-coding RNAs. 展开更多
关键词 circular SPONGE PROGRESSION
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Evaluation of Industrial IoT Service Providers with TOPSIS Based on Circular Intuitionistic Fuzzy Sets
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作者 ElifÇalo˘glu Büyükselçuk 《Computers, Materials & Continua》 SCIE EI 2024年第7期715-746,共32页
Industrial Internet of Things(IIoT)service providers have become increasingly important in the manufacturing industry due to their ability to gather and process vast amounts of data from connected devices,enabling man... Industrial Internet of Things(IIoT)service providers have become increasingly important in the manufacturing industry due to their ability to gather and process vast amounts of data from connected devices,enabling manufacturers to improve operational efficiency,reduce costs,and enhance product quality.These platforms provide manufacturers with real-time visibility into their production processes and supply chains,allowing them to optimize operations and make informed decisions.In addition,IIoT service providers can help manufacturers create new revenue streams through the development of innovative products and services and enable them to leverage the benefits of emerging technologies such as Artificial Intelligence(AI)and machine learning.Overall,the implementation of IIoT platforms in the manufacturing industry is crucial for companies seeking to remain competitive and meet the ever-increasing demands of customers in the digital age.In this study,the evaluation criteria to be considered in the selection of IIoT service provider in small andmedium-sized(SME)manufacturing enterprises will be determined and IIoT service providers alternatives will be evaluated using the technique for order preference by similarity to an ideal solution(TOPSIS)method based on circular intuitionistic fuzzy sets.Based on the assessments conducted in accordance with the literature review and expert consultations,a set of 8 selection criteria has been established.These criteria encompass industry expertise,customer support,flexibility and scalability,security,cost-effectiveness,reliability,data analytics,as well as compatibility and usability.Upon evaluating these criteria,it was observed that the security criterion holds the highest significance,succeeded by cost-effectiveness,data analytics,flexibility and scalability,reliability,and customer support criteria,in descending order of importance.Following the evaluation of seven distinct alternatives against these criteria,it was deduced that the A6 alternative,a German service provider,emerged as the most favorable option.The identical issue was addressed utilizing sensitivity analysis alongside various multi-criteria decision-making(MCDM)methods,and after comprehensive evaluation,the outcomes were assessed.Spearman’s correlation coefficient was computed to ascertain the association between the rankings derived from solving the problem using diverse MCDM methods. 展开更多
关键词 IIoT MANUFACTURING TOPSIS circular intuitionistic fuzzy sets
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On the spreading behavior of a droplet on a circular cylinder using the lattice Boltzmann method
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作者 杨帆 金虎 戴梦瑶 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期434-443,共10页
The study of a droplet spreading on a circular cylinder under gravity was carried out using the pseudo-potential lattice Boltzmann high-density ratios multiphase model with a non-ideal Peng–Robinson equation of state... The study of a droplet spreading on a circular cylinder under gravity was carried out using the pseudo-potential lattice Boltzmann high-density ratios multiphase model with a non-ideal Peng–Robinson equation of state. The calculation results indicate that the motion of the droplet on the cylinder can be divided into three stages: spreading, sliding, and aggregating.The contact length and contact time of a droplet on a cylindrical surface can be affected by factors such as the wettability gradient of the cylindrical wall, the Bond number, and droplet size. Furthermore, phase diagrams showing the relationship between Bond number, cylinder wall wettability gradient, and contact time as well as maximum contact length for three different droplet sizes are given. A theoretical foundation for additional research into the heat and mass transfer process between the droplet and the cylinder can be established by comprehending the variable rules of maximum contact length and contact time. 展开更多
关键词 lattice Boltzmann methods DROPLET circular cylinder wettability gradient
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Low-Complexity Reconstruction of Covariance Matrix in Hybrid Uniform Circular Array
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作者 Fu Zihao Liu Yinsheng Duan Hongtao 《China Communications》 SCIE CSCD 2024年第3期66-74,共9页
Spatial covariance matrix(SCM) is essential in many multi-antenna systems such as massive multiple-input multiple-output(MIMO). For multi-antenna systems operating at millimeter-wave bands, hybrid analog-digital struc... Spatial covariance matrix(SCM) is essential in many multi-antenna systems such as massive multiple-input multiple-output(MIMO). For multi-antenna systems operating at millimeter-wave bands, hybrid analog-digital structure has been widely adopted to reduce the cost of radio frequency chains.In this situation, signals received at the antennas are unavailable to the digital receiver, and as a consequence, traditional sample average approach cannot be used for SCM reconstruction in hybrid multi-antenna systems. To address this issue, beam sweeping algorithm(BSA) which can reconstruct the SCM effectively for a hybrid uniform linear array, has been proposed in our previous works. However, direct extension of BSA to a hybrid uniform circular array(UCA)will result in a huge computational burden. To this end, a low-complexity approach is proposed in this paper. By exploiting the symmetry features of SCM for the UCA, the number of unknowns can be reduced significantly and thus the complexity of reconstruction can be saved accordingly. Furthermore, an insightful analysis is also presented in this paper, showing that the reduction of the number of unknowns can also improve the accuracy of the reconstructed SCM. Simulation results are also shown to demonstrate the proposed approach. 展开更多
关键词 hybrid array MILLIMETER-WAVE spatial covariance matrix uniform circular array
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Knockdown of circular RNA (CircRNA)_001896 inhibits cervical cancer proliferation and stemness in vivo and in vitro
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作者 JIA SHAO CAN ZHANG +2 位作者 YAONAN TANG AIQIN HE WEIPEI ZHU 《BIOCELL》 SCIE 2024年第4期571-580,共10页
Objective:Previous studies indicated that aberrant circular RNA(circRNA)expression affects gene expression regulatory networks,leading to the aberrant activation of tumor pathways and promoting tumor cell growth.Howev... Objective:Previous studies indicated that aberrant circular RNA(circRNA)expression affects gene expression regulatory networks,leading to the aberrant activation of tumor pathways and promoting tumor cell growth.However,the expression,clinical significance,and effects on cell propagation,invasion,and dissemination of circRNA_001896 in cervical cancer(CC)tissues remain unclear.Methods:The Gene Expression Omnibus(GEO)datasets(GSE113696 and GSE102686)were used to examine differential circRNA expression in CC and adjacent tissues.The expression of circRNA_001896 was detected in 72 CC patients usingfluorescence quantitative PCR.Correlation analysis with clinical pathological features was performed through COX multivariate and univariate analysis.The effect of circRNA_001896 downregulation on CC cell propagation was examined using the cell counting kit-8(CCK-8)test,clonogenic,3D sphere formation,and in vivo tumorigenesis assays.Results:Intersection of the GSE113696 and GSE102686 datasets revealed an increased expression of four circRNAs,including circRNA_001896,in CC tissues.Fluorescence quantitative PCR confirmed circRNA_001896 as a circular RNA.High expression of circRNA_001896 was considerably associated with lymph node metastasis,International Federation of Gynecologists and Obstetricians(FIGO)stage,tumor diameter,and survival period in CC patients.Proportional hazards model(COX)univariate and multivariate analyses revealed that circRNA_001896 expressions are a distinct risk factor affecting CC patients’prognosis.Cellular functional experiments showed that downregulating circRNA_001896 substantially suppressed CC cell growth,colony formation,and 3D sphere-forming ability.In vivo,tumorigenesis analysis in nude mice demonstrated that downregulating circRNA_001896 remarkably reduced the in vivo proliferation capacity of CC cells.Conclusion:CircRNA_001896 is highly expressed in CC tissues and is substantially related to lymph node metastasis,FIGO stage,tumor size,and survival period in patients.Moreover,downregulating circRNA_001896 significantly inhibits both in vivo and in vitro propagation of CC cells.Therefore,circRNA_001896 might be used as a biomarker for targeted therapy in cervical cancer. 展开更多
关键词 Uterine cervical neoplasms RNA circular Cell proliferation Cancer stem cells
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A novel efficient energy absorber with free inversion of a metal foam-filled circular tube
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作者 Jianxun ZHANG Jinwen BAI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期1-14,共14页
In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analyticall... In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analytically and numerically. The theoretical analysis reveals that the energy is mainly dissipated through the radial bending of the metal circular tube, the circumferential expansion of the metal circular tube, and the metal filled-foam compression. The principle of energy conservation is used to derive the theoretical formula for the minimum compressive force of the MFFCT over free inversion under axial loading. Furthermore, the free inversion deformation characteristics of the MFFCT are analyzed numerically. The theoretical steady values are found to be in good agreement with the results of the finite element(FE) analysis. The effects of the average diameter of the metal tube, the wall thickness of the metal tube, and the filled-foam strength on the free inversion deformation of the MFFCT are considered. It is observed that in the steady deformation stage, the load-carrying and energy-absorbing capacities of the MFFCT increase with the increase in the average diameter of the metal tube, the wall thickness of the metal tube, or the filled-foam strength. The specific energy absorption(SEA) of free inversion of the MFFCT is significantly higher than that of the metal tube alone. 展开更多
关键词 metal foam-filled circular tube(MFFCT) free inversion load-carrying capacity energy absorption
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Impact of surface-reflected seismic waves on the seismic isolation performance of circular tunnel isolation layers
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作者 LU Jiahui LUO Junjie +3 位作者 HUANG Xiangyun HONG Junliang HE YanXin ZHOU Fulin 《Journal of Mountain Science》 SCIE CSCD 2024年第3期901-917,共17页
Seismic isolation is an effective strategy to mitigate the risk of seismic damage in tunnels.However,the impact of surface-reflected seismic waves on the effectiveness of tunnel isolation layers remains under explored... Seismic isolation is an effective strategy to mitigate the risk of seismic damage in tunnels.However,the impact of surface-reflected seismic waves on the effectiveness of tunnel isolation layers remains under explored.In this study,we employ the wave function expansion method to provide analytical solutions for the dynamic responses of linings in an elastic half-space and an infinite elastic space.By comparing the results of the two models,we investigate the seismic isolation effect of tunnel isolation layers induced by reflected seismic waves.Our findings reveal significant differences in the dynamic responses of the lining in the elastic half-space and the infinitely elastic space.Specifically,the dynamic stress concentration factor(DSCF)of the lining in the elastic half-space exhibits periodic fluctuations,influenced by the incident wave frequency and tunnel depth,while the DSCF in the infinitely elastic space remain stable.Overall,the seismic isolation application of the tunnel isolation layer is found to be less affected by surface-reflected seismic waves.Our results provide valuable insights for the design and assessment of the seismic isolation effect of tunnel isolation layers. 展开更多
关键词 circular tunnel seismic isolation Surface reflection Response of liners Wave-function expansion method
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Advances of N6-methyladenosine modification on circular RNA in hepatocellular carcinoma
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作者 CHU Feng-ran LIU Lu-zheng WU Jin-cai 《Journal of Hainan Medical University》 CAS 2024年第2期67-72,共6页
N6-methyladenosine(m6A)is a reversible epigenetic modification, which is one of the most abundant modifiers in eukaryotic cells and has been commonly reported in messenger RNAs and non-coding RNAs. The processing modi... N6-methyladenosine(m6A)is a reversible epigenetic modification, which is one of the most abundant modifiers in eukaryotic cells and has been commonly reported in messenger RNAs and non-coding RNAs. The processing modification of m6A regulates RNA transcription, processing, splicing, degradation, and translation, and plays an important role in the biological process of tumors. Circular RNA, which lacks the 5' cap structure, has been mistakenly regarded as a "junk sequence" generated by accidental shearing during the transcription process. However, it has been found that circRNAs can be involved in tumor invasion and metastasis through microRNAs, binding proteins, translated peptides, and m6A modifications. In this paper, we reviewed the role of m6A modifications in circRNA regulation and their functions in hepatocellular carcinoma and discussed their potential clinical applications and future development in this field. 展开更多
关键词 N6-methyladenosine circular RNA MODIFICATION Hepatocellular carcinoma
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Investigation on photonic crystal nanobeam cavity based on mixed diamond–circular holes
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作者 Jingtong Bin Kerui Feng +4 位作者 Shang Ma Ke Liu Yong Cheng Jing Chen Qifa Liu 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期63-70,共8页
A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using thefin... A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using thefinite-difference time-domain method,the parameters of the M-PCNC,including cavity thickness and width,lattice constant,and radii and numbers of holes,are optimized,with the quality factor Q and mode volume Vm as performance indicators.Mutual modulation of the lattice constant and hole radius enable the proposed M-PCNC to realize outstanding performance.The optimized cavity possesses a high quality factor Q 1.45105 and an ultra-small mode=×volume Vm 0.01(λ/n)[Zeng et al.,Opt Lett 2023:48;3981–3984]in the telecommunications wavelength range.Light can be progres-=sively squeezed in both the propagation direction and the perpendicular in-plane direction by a series of interlocked anti-slots and slots in the diamond-shaped hole structure.Thereby,the energy can be confined within a small mode volume to achieve an ultra-high Q/Vm ratio. 展开更多
关键词 Photonic crystal nanobeam cavity Mixed diamond–circular holes Slots and anti-slots FDTD simulation Quality factor Mode volume
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Circular and Adaptive Transformation of the Housing Stock towards a Regenerative Future
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作者 Cristiana Cellucci 《Journal of Civil Engineering and Architecture》 2024年第4期155-164,共10页
The transition from a linear economy to a CE(circular economy)has the potential to reduce resource use,environmental impacts,and waste in the built environment.Creating a CE in the built environment is therefore of fu... The transition from a linear economy to a CE(circular economy)has the potential to reduce resource use,environmental impacts,and waste in the built environment.Creating a CE in the built environment is therefore of fundamental importance to achieve a sustainable society.Through the application of a systemic approach that considers the building as a set of technological subsystems(e.g.vertical closures,roof,furniture,etc.),components(e.g.infill panels),and materials,this paper-starting from a review of the literature on the topic of the CE applied to construction-establishes a framework of circular design strategies and definitions that link the VRPs(value retention processes)framework,based on the R-imperatives,to the Design-for-X strategies.The first research objective is to develop a design tool for circular building components and technological subsystems. 展开更多
关键词 ADAPTABILITY SUSTAINABILITY circular transition REGENERATION REMANUFACTURING
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Valorization of Agricultural Residues for Hydrogen-Based Electricity Generation towards Circular Bioeconomy
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作者 Patience Afi Seglah Komikouma Apelike Wobuibe Neglo 《Open Journal of Energy Efficiency》 2024年第2期57-78,共22页
Global crises, notably climate shocks, degraded ecosystems, and growing energy demand, enforce sustainable production and consumption pathways. A circular bioeconomy offers the opportunities to actualize resource and ... Global crises, notably climate shocks, degraded ecosystems, and growing energy demand, enforce sustainable production and consumption pathways. A circular bioeconomy offers the opportunities to actualize resource and eco-efficiency enhancement, valorization of waste streams, reduction of fossil energy and greenhouse gas (GHG) emissions. Albeit biomass resources are a potential feedstock for bio-hydrogen (bio-H2) production, Ghana’s agricultural residues are not fully utilized. This paper examines the economic and environmental impact of bio-H2 electricity generation using agricultural residues in Ghana. The bio-H2 potential was determined based on biogas steam reforming (BSR). The research highlights that BSR could generate 2617 kt of bio-H2, corresponding to 2.78% of the global hydrogen demand. Yam and maize residues contribute 50.47% of the bio-H2 produced, while millet residues have the most negligible share. A tonne of residues could produce 16.59 kg of bio-H2 and 29.83 kWh of electricity. A total of 4,705.89 GWh of electricity produced could replace the consumption of 21.92% of Ghana’s electricity. The economic viability reveals that electricity cost is $0.174/kWh and has a positive net present value of $2135550609.45 with a benefit-to-cost ratio of 1.26. The fossil diesel displaced is 1421.09 ML, and 3862.55 kt CO2eq of carbon emissions decreased corresponding to an annual reduction potential of 386.26 kt CO2eq. This accounts for reducing 10.26% of Ghana’s GHG emissions. The study demonstrates that hydrogen-based electricity production as an energy transition is a strategic innovation pillar to advance the circular bioeconomy and achieve sustainable development goals. 展开更多
关键词 Agricultural Residues Biogas Steam Reforming BIO-HYDROGEN ELECTRICITY circular Bioeconomy
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An Integrated Building Information Modeling (BIM) and Circular Economy (CE) Model for the Management of Construction and Deconstruction Waste Based on Construction Methods
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作者 Nkechi Mcneil-Ayuk Ahmad Jrade 《Open Journal of Civil Engineering》 2024年第2期168-195,共28页
As the climate change signs become more noticeable, the concern to prioritize sustainability within the AEC industry intensifies. This particularly pertained to issues related to the demand of resources, the excessive... As the climate change signs become more noticeable, the concern to prioritize sustainability within the AEC industry intensifies. This particularly pertained to issues related to the demand of resources, the excessive consumption of raw materials, and the associated generated waste. Presently, the construction industry is ranked among the industries that are accountable for the global generation of solid waste and energy consumption, leading to detrimental environmental effects. Nonetheless, over the years, construction methods, technological innovations, and building practices have made considerable progress, influenced by a growing emphasis on sustainability, especially in energy conservation and in adopting the Industrialized Production layer of Construction 4.0 (i.e., modular prefabrication, 3D concrete printing, and BIM). The concept of Circular Economy (CE) has been identified as a potential solution to achieve sustainability in building construction through the design, construction, and end-of-life deconstruction processes that enhance the management of waste based on the framework that is related to reducing, reusing, and recycling. Moreover, information and data related to geolocation complement advanced digital technologies by providing a collaborative platform that supports the application of CE as a practical approach to sustainability. Thus, this study will provide a straightforward methodology for developing a model that integrates BIM and sustainable design with Circular Economy’s concept to enhance the sustainability of construction projects to minimize their waste based on various construction methods (i.e., conventional, modular, and 3D concrete printing). The proposed model interrelates tools and data for the evaluation and planning strategies for the construction and deconstruction waste (CDW) management at the design stage, including estimating the quantities of the wasted materials, quantifying the production rates of selected equipment for the waste handling (loading and hauling) at the various stages of a project as well their associated cost. The proposed model will help users to calculate the quantity of construction and deconstruction waste (CDW) during the design of buildings based on their different construction methods at the early stage by using the concept of Design for Deconstruction (DfD);sustainable construction methods;and deconstruction process for waste management, which will lead to the suitable construction method. 展开更多
关键词 circular Economy (CE) SUSTAINABILITY Construction 4.0 CDW Management Technological Innovations
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Using Circular Economics Strategies to Manage Tourism on Remote Islands:A SMART Approach
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作者 Colm Barcoe James Hanrahan Garvan Whelan 《Journal of Tourism and Hospitality Management》 2024年第1期18-33,共16页
Circular economics theory offers destination managers of remote islands a solution-oriented approach to environmental sustainability. This paper examines the practical benefits of this theory that will support the dev... Circular economics theory offers destination managers of remote islands a solution-oriented approach to environmental sustainability. This paper examines the practical benefits of this theory that will support the development of a circular economy regarding sustainable island tourism (SIT). The aim of this paper is to inform discussions regarding the feasibility of applying a practice theory that emphasises changes in the behaviours across three segments, visitors, residents, and enterprises using SMART technologies. To achieve this objective, a SMART indicator system (SIS) was used to identify current practices that would support a circular economy (CE). The key innovation of this study is the creation of a proposed framework that may inform best practices for SIT in the future. The findings highlight the potential opportunity of evidenced-based planning to deliver a circular economy strategy (CES) for remote islands in the future. These insights can potentially impact the way that local authorities and destination managers approach the planning of tourism for six islands along the west coast of Ireland. 展开更多
关键词 circular economy SMART indicator system sustainable island tourism proposed framework
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Carbon Capture Technologies in OAPEC Member Countries and the Circular Carbon Economy: A Roadmap to Zero Emissions by 2050
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作者 Salem Baidas 《Open Journal of Energy Efficiency》 2024年第2期25-37,共13页
Several Organization of Arab Petroleum Exporting Countries (OAPEC) member states (OMSs) have updated their nationally determined contributions (NDCs) with the aim of achieving zero carbon emissions by 2050. Carbon neu... Several Organization of Arab Petroleum Exporting Countries (OAPEC) member states (OMSs) have updated their nationally determined contributions (NDCs) with the aim of achieving zero carbon emissions by 2050. Carbon neutrality requires shifting from a linear carbon economy (LCE) to a circular carbon economy (CCE). Carbon capture and storage (CCS) technologies, including reduction, recycle, reuse, removal, and storage technologies, represent an important strategy for achieving such a shift. Herein, we investigate the effects of CCS technology adoption in six OMSs—namely the Kingdom of Saudi Arabia (KSA), Qatar, the United Arab Emirates (UAE), Kuwait, Algeria, and Iraq—by examining their Circular Carbon Economy Index (CCEI) scores, which reflect compliance with CCE-transition policies. Total CCEI, current performance CCEI dimension, and future enabler CCEI dimensions scores were compared among the aforementioned six OMSs and relative to Norway, which was used as a global-high CCEI reference standard. Specifically, CCEI general scope and CCEI oil scope dimension scores were compared. The KSA, Qatar, the UAE, and Kuwait had higher CCEI scores than Algeria and Iraq, reflecting their greater adoption of CCE-transition policies and greater emission-reducing modernization investments. The current performance CCEI scores of Algeria and Iraq appear to be buttressed to some extent by their greater natural carbon sink resources. Based on the findings, we recommend specific actions for OMSs to enhance their CCE transitions and mitigate the negative impacts associated with the associated investments, including: taking rapid practical steps to eliminate carbon oil industry emissions;detailed CCS planning by national oil companies;international cooperation and coordination;and increased investment in domestic CCS utilization infrastructure. 展开更多
关键词 OAPEC PETROLEUM Fossil Fuels Carbon Capture and Storage circular Carbon Economy
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Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view
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作者 Wei Wang Jiaqi Liu +2 位作者 Shiyao Lin Baokui Geng Zhongjiao Shi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期211-221,共11页
In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated... In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV constraint.The boundary time-varying integral barrier Lyapunov function(IBLF)is employed in backstepping design to constrain the body line-of-sight(BLOS)in IEGC system to fit a circular FOV.Then,the nonlinear adaptive controller is designed to estimate the changing aerodynamic parameters.The generalized extended state observer(GESO)is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking accuracy.Furthermore,the command filters are used to solve the"differential expansion"problem during the backstepping design.The Lyapunov theory is used to prove the stability of the overall closed-loop IEGC system.Finally,the simulation results validate the integrated system's effectiveness,achieving high accuracy strikes against maneuvering targets. 展开更多
关键词 Integrated estimation guidance and control circular field-of-view Time-varying integral barrier Lyapunov function Command filtered backstepping control Nonlinear adaptive control Extended state observer
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Designing a Dual-Feed Circular Polarization Antenna
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作者 Binghao Zeng Haokui Zhu 《Journal of Electronic Research and Application》 2024年第3期255-261,共7页
This paper describes a novel dual-feed circularly polarized antenna,and the dual feeding mode is realized by grooving on the antenna radiator.The antenna utilizes air dielectric material to meet the requirements of lo... This paper describes a novel dual-feed circularly polarized antenna,and the dual feeding mode is realized by grooving on the antenna radiator.The antenna utilizes air dielectric material to meet the requirements of low weight and cost.Test results demonstrate that the antenna exhibits capacitive loading between the metal antenna patch and the ground floor,allowing for adjustment of the working frequency of the dual-feed circularly polarized microstrip antenna.Specifically,the original center frequency of 2.264 GHz was reduced to 1.582 GHz,facilitating antenna miniaturization and broad bandwidth.With a return loss(S11)below-10 dB,a bandwidth of 72 MHz(1.552-1.624 GHz)was obtained.Additionally,the dual-feed microstrip antenna incorporates a 90°bridge,resulting in circular polarization gains of 2.26 dBi at 1.561 GHz and 2.45 dBi at 1.575 GHz.Overall,the antenna design offers a large working bandwidth and excellent circular polarization characteristics,making it suitable for a wide range of applications in satellite navigation and positioning terminals. 展开更多
关键词 Air dielectric circular polarization Dual-feed Microstrip antenna
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Circular RNA_0015278与甲状腺乳头状癌及临床特征的相关性
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作者 丁华杰 杨绍石 +3 位作者 李莎 史华宁 龚雪 那磊 《河北医药》 CAS 2023年第19期2945-2947,2951,共4页
目的探讨Circular RNA_0015278(circ_0015278)与甲状腺乳头状癌(PTC)及其临床病理特征的相关性。方法回顾分析手术切除的甲状腺乳头状癌患者200例,采用逆转录定量聚合酶链反应(RT-qPCR)检测Circular RNA_0015278在甲状腺乳头状癌(PTC)... 目的探讨Circular RNA_0015278(circ_0015278)与甲状腺乳头状癌(PTC)及其临床病理特征的相关性。方法回顾分析手术切除的甲状腺乳头状癌患者200例,采用逆转录定量聚合酶链反应(RT-qPCR)检测Circular RNA_0015278在甲状腺乳头状癌(PTC)及癌旁组织的表达。结果与癌旁组织比较,甲状腺乳头状癌(PTC)中Circular RNA_0015278表达显著降低(Z=-12.122,P<0.001),ROC分析显示,以相对表达量0.743为截断值,可较好的鉴别PTC肿瘤及癌旁组织(AUC:0.903,95%CI:0.873~0.933)。而PTC肿瘤中Circular RNA_0015278的高表达与患者年龄<45岁(Z=-2.319,P=0.020)、无甲状腺外侵犯(Z=-2.042,P=0.041)、无淋巴结转移(Z=-2.494,P=0.013)及低pTNM分期(Z=-3.719,P=0.001)相关(P<0.05)。而未发现与性别(Z=-1.323,P=0.186)、肿瘤大小(Z=-1.273,P=0.203)具有相关性(P>0.05)。结论PTC肿瘤中Circular RNA_0015278的表达显著降低,而其在PTC肿瘤中高表达与患者年龄<45岁、无甲状腺外侵犯、无淋巴结转移及低pTNM分期具有相关性。 展开更多
关键词 circular RNA_0015278 甲状腺乳头状癌 临床特征
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Waste-Derived Catalysts for Water Electrolysis:Circular Economy-Driven Sustainable Green Hydrogen Energy 被引量:2
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作者 Zhijie Chen Sining Yun +7 位作者 Lan Wu Jiaqi Zhang Xingdong Shi Wei Wei Yiwen Liu Renji Zheng Ning Han Bing-Jie Ni 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第1期43-79,共37页
The sustainable production of green hydrogen via water electrolysis necessitates cost-effective electrocatalysts.By following the circular economy principle,the utilization of waste-derived catalysts significantly pro... The sustainable production of green hydrogen via water electrolysis necessitates cost-effective electrocatalysts.By following the circular economy principle,the utilization of waste-derived catalysts significantly promotes the sustainable development of green hydrogen energy.Currently,diverse waste-derived catalysts have exhibited excellent catalytic performance toward hydrogen evolution reaction(HER),oxygen evolution reaction(OER),and overall water electrolysis(OWE).Herein,we systematically examine recent achievements in waste-derived electrocatalysts for water electrolysis.The general principles of water electrolysis and design principles of efficient electrocatalysts are discussed,followed by the illustration of current strategies for transforming wastes into electrocatalysts.Then,applications of waste-derived catalysts(i.e.,carbon-based catalysts,transitional metal-based catalysts,and carbon-based heterostructure catalysts)in HER,OER,and OWE are reviewed successively.An emphasis is put on correlating the catalysts’structure-performance relationship.Also,challenges and research directions in this booming field are finally highlighted.This review would provide useful insights into the design,synthesis,and applications of waste-derived electrocatalysts,and thus accelerate the development of the circular economy-driven green hydrogen energy scheme. 展开更多
关键词 Waste-derived electrocatalysts Water splitting Sustainable hydrogen energy Catalyst design circular economy
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Rockburst process and strength-weakening effect of the high-stress circular tunnel under internal unloading 被引量:1
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作者 Fengqiang Gong Wuxing Wu Li Ren 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期864-885,共22页
To investigate the influence of unloading effect of a circular tunnel face on rockburst process,by innovatively combining rock drilling unloading devices and triaxial systems,the strain rockburst simulation under the ... To investigate the influence of unloading effect of a circular tunnel face on rockburst process,by innovatively combining rock drilling unloading devices and triaxial systems,the strain rockburst simulation under the entire stress path of“high initial stressþinternal unloadingþstress adjustment”(HUS test)was realized for the intact cubic red sandstone samples(100 mm×100 mm×100 mm).Comparative tests were conducted on cubic red sandstone samples with prefabricated circular holes(425 mm)under the stress path of“prefabricated circular hole+þhigh initial stress+stress adjustment”(PHS test),thereby highlighting the influence of internal unloading on rockburst failure.The test results revealed that with an increase in vertical stress,the sidewalls in both the HUS and PHS tests suffered strain rockburst failure.Compared with the PHS test,the initial failure stress in the HUS test is lower,and it is easier to induce sidewall rockbursts.This indicates that the internal unloading influences the sidewall failure,causing an obvious strength-weakening effect,which becomes more significant with an increase in buried depth.The strain rockburst failure was more severe in the HUS test owing to the influence of internal unloading.V-shaped rockburst pits were formed in the HUS tests,whereas in the PHS test,arcshaped rockburst pits were produced.It was also found that strain rockburst failure may occur only when the rock has a certain degree of rockburst proneness. 展开更多
关键词 ROCKBURST UNLOADING Strength-weakening effect Deep rock V-shaped notch circular tunnel
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Controlled transition to different proton acceleration regimes:Near-critical-density plasmas driven by circularly polarized few-cycle pulses
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作者 Shivani Choudhary De Marco Sudipta Mondal +1 位作者 Daniele Margarone Subhendu Kahaly 《Matter and Radiation at Extremes》 SCIE EI CSCD 2023年第5期1-18,共18页
A controlled transition between two different ion acceleration mechanisms would pave the way to achieving different ion energies and spectral features within the same experimental set up,depending on the region of ope... A controlled transition between two different ion acceleration mechanisms would pave the way to achieving different ion energies and spectral features within the same experimental set up,depending on the region of operation.Based on numerical simulations conducted over a wide range of experimentally achievable parameter space,reported here is a comprehensive investigation of the different facets of ion acceleration by relativistically intense circularly polarized laser pulses interacting with thin near-critical-density plasma targets.The results show that the plasma thickness,exponential density gradient,and laser frequency chirp can be controlled to switch the interaction from the transparent operating regime to the opaque one,thereby enabling the choice of a Maxwellian-like ion energy distribution with a cutoff energy in the relativistically transparent regime or a quasi-monoenergetic spectrum in the opaque regime.Next,it is established that a multispecies target configuration can be used effectively for optimal generation of quasi-monoenergetic ion bunches of a desired species.Finally,the feasibility is demonstrated for generating monoenergetic proton beams with energy peak atℰ≈20–40 MeV and a narrow energy spread ofΔℰ/ℰ≈18%–28.6%confined within a divergence angle of∼175 mrad at a reasonable laser peak intensity of I0≃5.4×10^(20)W/cm^(2). 展开更多
关键词 ACCELERATION REGIME circular
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