Triad-displaced ULAs configuration for non-circular sources with larger continuous virtual aperture and enhanced degrees of freedom

Non-uniform linear array(NULA)configurations are well renowned due to their structural ability for providing increased degrees of freedom(DOF)and wider array aperture than uniform linear arrays(ULAs).These characteristics play a significant role in improving the direction-of-arrival(DOA)estimation accuracy.However,most of the existing NULA geometries are primarily applicable to circular sources(CSs),while they limitedly improve the DOF and continuous virtual aperture for noncircular sources(NCSs).Toward this purpose,we present a triaddisplaced ULAs(Tdis-ULAs)configuration for NCS.The TdisULAs structure generally consists of three ULAs,which are appropriately placed.The proposed antenna array approach fully exploits the non-circular characteristics of the sources.Given the same number of elements,the Tdis-ULAs design achieves more DOF and larger hole-free co-array aperture than its sparse array competitors.Advantageously,the number of uniform DOF,optimal distribution of elements among the ULAs,and precise element positions are uniquely determined by the closed-form expressions.Moreover,the proposed array also produces a filled resulting co-array.Numerical simulations are conducted to show the performance advantages of the proposed Tdis-ULAs configuration over its counterpart designs.

Role of exosomal circular RNAs as microRNA sponges and potential targeting for suppressing hepatocellular carcinoma growth and progression

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.

Spray Characteristics of Non-Circular Nozzle in Air-Assisted Injection System

In order to analyze the spray characteristics of non-circular nozzle holes based on the air-assisted spray system, the spray characteristics of circular and non-circular nozzles were studied under the pressure of 0.2-0.6 MPa and the spray volume of 1000-5000 mL/h. Elliptical nozzle and triangular nozzle are classified as non-circular geometries. The spray cone angle was measured by processing the spray image captured by a CCD camera. The measured spray cone angles of the circular nozzles were analyzed, and the axis switching phenomenon of minor plane of elliptical nozzle was found during the test. Among the three shapes of nozzles, the elliptical nozzle had the largest spray cone angle, and the triangular nozzle had the smallest. The velocity field obtained depended on the PIV system. The results show that for axial velocity, elliptical orifice spray has greater kinetic energy and smaller droplet size under the same working parameters. Compared with the circular and elliptical nozzles, triangular orifice reached maximum spray velocity the fastest, but its velocity decay was the fastest. For radial velocity, away from the axis, the spray velocity of the elliptical orifice was less affected by the injection parameters, and the velocity was less than that of circular orifice and triangle orifice. Increasing air pressure will weaken radial propagation. The increase of liquid spraying rate had no remarkable effect on the increase of spraying rate. The results of particle size analysis show that the particle size of the non-circular orifice is reduced compared with that of the circular orifice, which promotes the breakup of droplets to a certain extent and enhances the atomization effect.

Evaluation of Industrial IoT Service Providers with TOPSIS Based on Circular Intuitionistic Fuzzy Sets

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.

On the spreading behavior of a droplet on a circular cylinder using the lattice Boltzmann method

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.

Optical storage of circular airy beam in atomic vapor

The realization of quantum storage of spatial light field is of great significance to the construction of high-dimensional quantum repeater.In this paper,we experimentally realize the storage and retrieval of circular Airy beams(CABs)by using theΛ-type three-level energy system based on the electromagnetically induced transparency in a hot rubidium atomic vapor cell.The weak probe beam field is modulated with phase distribution of CABs by a spatial light modulator.We store the probe circular Airy beam(CAB)into the rubidium atomic vapor cell and retrieve it after the demanded delay.We quantitatively analyze the storage results and give corresponding theoretical explanations.Moreover,we investigate the autofocusing and self-healing effect of the retrieved CAB,which indicates that the properties and beam shape of CAB maintain well after storage.Our work will have potential applications in the storage of high-dimensional quantum information,and is also useful for improving the channel capacities of quantum internet.

Low-Complexity Reconstruction of Covariance Matrix in Hybrid Uniform Circular Array

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.

Temperature-Induced Unfolding Pathway of Staphylococcal Enterotoxin B:Insights from Circular Dichroism and Molecular Dynamics Simulation

In this study,circular dichroism(CD)and molecular dynamics(MD)simulation were used to investigate the thermal unfolding pathway of staphylococcal enterotoxin B(SEB)at temperatures of 298–371 and 298–500 K,and the relationship between the experimental and simulation results were explored.Our computational findings on the secondary structure of SEB showed that at room temperature,the CD spectroscopic results were highly consistent with the MD results.Moreover,under heating conditions,the changing trends of helix,sheet and random coil obtained by CD spectral fitting were highly consistent with those obtained by MD.In order to gain a deeper understanding of the thermal stability mechanism of SEB,the MD trajectories were analyzed in terms of root mean square deviation(RMSD),secondary structure assignment(SSA),radius of gyration(R_(g)),free energy surfaces(FES),solvent-accessible surface area(SASA),hydrogen bonds and salt bridges.The results showed that at low heating temperature,domain Ⅰ without loops(omitting the mobile loop region)mainly relied on hydrophobic interaction to maintain its thermal stability,whereas the thermal stability of domain Ⅱ was mainly controlled by salt bridges and hydrogen bonds.Under high heating temperature conditions,the hydrophobic interactions in domain Ⅰ without loops were destroyed and the secondary structure was almost completely lost,while domain Ⅱ could still rely on salt bridges as molecular staples to barely maintain the stability of the secondary structure.These results help us to understand the thermodynamic and kinetic mechanisms that maintain the thermal stability of SEB at the molecular level,and provide a direction for establishing safer and more effective food sterilization processes.

Knockdown of circular RNA (CircRNA)_001896 inhibits cervical cancer proliferation and stemness in vivo and in vitro

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.

A novel efficient energy absorber with free inversion of a metal foam-filled circular tube

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.

Temperature effects on the failure of deep circular tunnel under true-triaxial compression

The failure characteristics of thermal treated surrounding rocks should be studied to evaluate the stability and safety of deep ground engineering under high-ground-temperature and high-ground-stress conditions.The failure process of the inner walls of fine-grained granite specimens at different temperatures(25–600℃)was analyzed using a true-triaxial test system.The failure process,peak intensity,overall morphology(characteristics after failure),rock fragment characteristics,and acoustic emission(AE)characteristics were analyzed.The results showed that for the aforementioned type of granite specimens,the trend of the failure stress conditions changed with respect to the critical temperature(200℃).When the temperature was less than 200℃,the initial failure stress increased,final failure stress increased,and failure severity decreased.When the temperature exceeded 200℃,the initial failure stress decreased,final failure stress decreased,and failure severity increased.When the temperature was 600℃,the initial and final failure stresses of the specimens decreased by 60.93%and 19.77%compared with those at 200℃,respectively.The numerical results obtained with the software RFPA3D-Thermal were used to analyze the effect of temperature on the specimen and reveal the mechanism of the failure process in the deep tunnel surrounding rock.

Development and Application of Ultrafast Circular Dichroism Spectroscopy Techniques

Chirality hold broad applications in life sciences,quantum devices,and various other areas.Traditionally,molecular chirality can be characterized by using steady-state circular dichroism spectroscopy.However,the techniques that can characterize excited state chirality are progressively capturing the public interest as it can provide the dynamic information for chirality generation and transfer.In this review,we focus on the theoretical background and the developmental history of femtosecond time-resolved circular dichroism spectroscopy(TRCD)techniques around the world.Additionally,we provide examples to showcase the utility of these techniques in the analysis of the dynamical molecular chemical structures,the investigation of molecular chirality generation,and the detection of electron spin dynamics in semiconductor quantum dots.

Impact of surface-reflected seismic waves on the seismic isolation performance of circular tunnel isolation layers

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.

Compressive properties of glue-laminated timber circular post modified by basalt fiber reinforced polymer

Glued timber structure is one of the main forms of modern wood architecture,which has gradually developed towards mid-and high-rise buildings.Glue-laminated timber(GLT)is comprised of several laminates of parallel-to-grain dimension lumber that are bonded together with durable,moisture resistant structural adhesives.GLT can be used in horizontal applications as a beam and in vertical applications as a post.So,its compressive performance has a significant impact on structural safety.Fiber reinforced polymers(FRPs)were commonly used to improve the bearing capacity of GLT components,and the structural and process parameters largely determined the reinforcement effect.This study was aimed at investigating the influence of structural and process parameters on the axial compression performance of GLT components.Three wrapping methods(middle-part,end-part and full wrapping)and three lengths(0.6,0.8,and 1.0 m)of wood post specimens were designed in this work and the axial compression performance and ductility of GLT post specimens modified by basalt fiber reinforced polymer(BFRP)were studied.The results showed that the effect of different BFRP wrapping methods on the compressive strength and elastic modulus of laminated wood was not statistically significant(P>0.05).The compressive bearing capacity of unreinforced GLT posts decreased with the increase of aspect ratio.The GLT posts with middle-part and end-part wrapping still followed this pattern,while the compressive bearing capacity of GLT posts with full wrapping showed a pattern of first decreasing and then increasing.For GLT with low aspect ratios(4.0 or 5.3),there was no correlation between the wrapping method and the compressive bearing capacity,while the compressive bearing capacity of GLT with a high aspect ratio(6.7)for middle-part,end-part and full wrapping increased by 3.5%,7.5%and 9.7%,respectively.Compared to the unreinforced group,the ultimate axial compressive strength and modulus of elasticity(MOE)of the 6-E series specimens reinforced at both ends decreased by 2.58%and 6.70%,respectively.The ultimate axial compressive strength of the 8-E specimens reinforced at both ends increased by 8.62%and the MOE decreased by 1.91%.The compressive strength of the 10-E specimens reinforced at both ends increased by 7.51%and the MOE increased by 8.14%.The failure modes of GLT with different aspects were consistent under the same BFRP wrapping,while the failure modes of GLT with the same aspect ratio were different for different BFRP wrapping methods.The ductility performance of GLT with different aspects ratio was improved by the BFRP wrapping.

Kinematic-mapping-model-guided analysis and optimization of 2-PSS&1-RR circular-rail parallel mechanism for fully steerable phased array antennas

This paper presents a systematic methodology for analyzing and optimizing an innovative antenna mount designed for phased array antennas, implemented through a novel 2-PSS&1-RR circular-rail parallel mechanism. Initially, a comparative motion analysis between the 3D model of the mount and its full-scale prototype is conducted to validate effectiveness. Given the inherent complexity, a kinematic mapping model is established between the mount and the crank-slider linkage, providing a guiding framework for subsequent analysis and optimization. Guided by this model, feasible inverse and forward solutions are derived, enabling precise identification of stiffness singularities. The concept of singularity distance is thus introduced to reflect the structural stiffness of the mount. Subsequently, also guided by the mapping model, a heuristic algorithm incorporating two backtracking procedures is developed to reduce the mount's mass. Additionally, a parametric finite-element model is employed to explore the relation between singularity distance and structural stiffness. The results indicate a significant reduction(about 16%) in the antenna mount's mass through the developed algorithm, while highlighting the singularity distance as an effective stiffness indicator for this type of antenna mount.

Advances of N6-methyladenosine modification on circular RNA in hepatocellular carcinoma

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.

Circular RNA circ_0003609 ameliorates hypertrophied ligamentum flavum by regulating the miR-155/SIRT1 axis

Background:Hypertrophy of the ligamentumflavum(HLF)is a common contributor to spinal stenosis which results in significant neurological impairments.Circular RNA(circRNA)circ_0003609 has been linked to HLF;however,the exact mechanism by which it causes this disease is unclear.Methods:Circ_0003609 expressions were regulated in HLF cells by overexpression vectors and RNA interference.Cell proliferation andfibrosis-related gene expression were checked by the Cell Counting Kit-8(CCK-8)assay and western blotting.CircBank’s prediction of the association between miR-155 and circ_0003609 was supported by a dual-luciferase reporter experiment.The function of the miR-155/sirtuin 1(SIRT1)axis in controlling HLFfibrosis was further examined.Results:Overexpression of circ_0003609 suppressed HLF cell propagation andfibrosis compared to its silencing.It was found that circ_0003609 served as the sponge for miR-155 and that the circ_0003609/miR-155 axis controlled thefibrosis of HLF cells.It was found that circ_0003609 acted as a sponge for miR-155,regulating thefibrosis of HLF cells.Further,miR-155 targets SIRT1,and the miR-155/SIRT1 axis promotes HLF cellfibrosis.Conclusion:Circ_0003609 ameliorates hypertrophied ligamentumflavum(LF)by modulating the miR-155/SIRT1 axis,indicating a potential treatment approach for HLF.

Promoting sustainable consumption and circular economy:the intention of Vietnamese youth consumers to purchase products made from recycled plastics

Recycling is viewed as a key component in a circular economy and serves as an ideal solution for promoting sustainability.During the global plastic crisis,plastic recycling practices have been adopted worldwide,leading to the production of various products made from recycled plastics(PRP).Nevertheless,a gap persists between consumption and demand for such products,which is primarily attributed to a lack of comprehension from the consumer perspective.Given the pivotal role consumers play in the adoption of these products,this study explores consumers’intentions to purchase PRP.This is particularly significant in Vietnam,which is an emerging economy aspiring to achieve the objectives of a circular economy and sustainable development.Utilizing an integrated cognitive-emotional framework comprising the Valence Theory and the Norm Activation Model,data from 564 Vietnamese students were gathered and analyzed using structural equation modeling.The results show that awareness of consequences is a major driver of consumer purchase intentions,followed by perceived ease of application and monetary incentives.The results also indicate that health concerns have the strongest effect on purchase intention and in the negative side,meaning that the health-related risk is the primary concern for consumers during the decision-making process.This research holds substantial value for academics and managers,as it aids in the theoretical exploration and the formulation of strategies to improve consumer acceptance of PRP.

Investigation on photonic crystal nanobeam cavity based on mixed diamond–circular holes

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.

Circular and Adaptive Transformation of the Housing Stock towards a Regenerative Future

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.