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Life Origin in the Milky Way Galaxy: III. Spatial Distribution of Overheated Stars in the Solar Neighborhood
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作者 Alexander N. Safronov 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期693-709,共17页
A concept of ensemble averaged stellar reactors is developed to study the dynamics of processes occurring in stars, allocated in the ~200 pc solar neighborhood. According to the effective temperature value, four stell... A concept of ensemble averaged stellar reactors is developed to study the dynamics of processes occurring in stars, allocated in the ~200 pc solar neighborhood. According to the effective temperature value, four stellar classes are identified, for which the correlation coefficients and standard deviation are counted. The theory of the buoyancy terrestial elements is generalized to stellar systems. It was suggested that stars are over-heated due to the shift parameters of the nuclear processes occurring inside the stars, which leads to the synthesis of transuranium elements until the achievement of a critical nuclear mass and star explosion. The heavy transuranium elements sink downward and are concentrated in the stellar depth layers. The physical explanation of the existence of the critical Chandrasekhar star limit has been offered. Based on the spatial analysis of overheated stars, it was suggested that the withdrawal of the stellar reactor from the equilibrium state is a consequence of extragalactic compression inside the galaxy arm due to the arm spirality (not to be confused with the spirality of the galaxy itself). 展开更多
关键词 Stellar Nucleogenesis Ensemble-Averaged Stellar Reactor Overheated Stars Chandrasekhar Stellar Limit Arm spirality
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Recent advances in the application of MXenes for neural tissue engineering and regeneration 被引量:1
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作者 Menghui Liao Qingyue Cui +7 位作者 Yangnan Hu Jiayue Xing Danqi Wu Shasha Zheng Yu Zhao Yafeng Yu Jingwu Sun Renjie Chai 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期258-263,共6页
Transition metal carbides and nitrides(MXenes)are crystal nanomaterials with a number of surface functional groups such as fluorine,hydroxyl,and oxygen,which can be used as carriers for proteins and drugs.MXenes have ... Transition metal carbides and nitrides(MXenes)are crystal nanomaterials with a number of surface functional groups such as fluorine,hydroxyl,and oxygen,which can be used as carriers for proteins and drugs.MXenes have excellent biocompatibility,electrical conductivity,surface hydrophilicity,mechanical properties and easy surface modification.However,at present,the stability of most MXenes needs to be improved,and more synthesis methods need to be explored.MXenes are good substrates for nerve cell regeneration and nerve reconstruction,which have broad application prospects in the repair of nervous system injury.Regarding the application of MXenes in neuroscience,mainly at the cellular level,the long-term in vivo biosafety and effects also need to be further explored.This review focuses on the progress of using MXenes in nerve regeneration over the last few years;discussing preparation of MXenes and their biocompatibility with different cells as well as the regulation by MXenes of nerve cell regeneration in two-dimensional and three-dimensional environments in vitro.MXenes have great potential in regulating the proliferation,differentiation,and maturation of nerve cells and in promoting regeneration and recovery after nerve injury.In addition,this review also presents the main challenges during optimization processes,such as the preparation of stable MXenes and long-term in vivo biosafety,and further discusses future directions in neural tissue engineering. 展开更多
关键词 HYDROGELS MXenes nerve regeneration neural cells neural stem cells ORGANOIDS spiral ganglion neurons
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Numerical and experimental study on the falling film flow characteristics with the effect of co-current gas flow in hydrogen liquefaction process 被引量:1
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作者 Chong-Zheng Sun Yu-Xing Li +2 位作者 Hui Han Xiao-Yi Geng Xiao Lu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1369-1384,共16页
Liquid hydrogen storage and transportation is an effective method for large-scale transportation and utilization of hydrogen energy. Revealing the flow mechanism of cryogenic working fluid is the key to optimize heat ... Liquid hydrogen storage and transportation is an effective method for large-scale transportation and utilization of hydrogen energy. Revealing the flow mechanism of cryogenic working fluid is the key to optimize heat exchanger structure and hydrogen liquefaction process(LH2). The methods of cryogenic visualization experiment, theoretical analysis and numerical simulation are conducted to study the falling film flow characteristics with the effect of co-current gas flow in LH2spiral wound heat exchanger.The results show that the flow rate of mixed refrigerant has a great influence on liquid film spreading process, falling film flow pattern and heat transfer performance. The liquid film of LH2mixed refrigerant with column flow pattern can not uniformly and completely cover the tube wall surface. As liquid flow rate increases, the falling film flow pattern evolves into sheet-column flow and sheet flow, and liquid film completely covers the surface of tube wall. With the increase of shear effect of gas-phase mixed refrigerant in the same direction, the liquid film gradually becomes unstable, and the flow pattern eventually evolves into a mist flow. 展开更多
关键词 Hydrogen liquefaction Spiral wound heat exchanger Flow pattern transition Falling film flow
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Performance analysis of single-focus phase singularity based on elliptical reflective annulus quadrangle-element coded spiral zone plates
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作者 臧华平 王宝珍 +7 位作者 郑程龙 魏来 范全平 王少义 杨祖华 周维民 曹磊峰 郭海中 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期441-448,共8页
Optical vortices generated by the conventional vortex lens are usually disturbed by the undesired higher-order foci,which may lead to additional artifacts and thus degrade the contrast sensitivity. In this work, we pr... Optical vortices generated by the conventional vortex lens are usually disturbed by the undesired higher-order foci,which may lead to additional artifacts and thus degrade the contrast sensitivity. In this work, we propose an efficient methodology to combine the merit of elliptical reflective zone plates(ERZPs) and the advantage of spiral zone plates(SZPs) in establishing a specific single optical element, termed elliptical reflective annulus quadrangle-element coded spiral zone plates(ERAQSZPs) to generate single-focus phase singularity. Differing from the abrupt reflectance of the ERZPs, a series of randomly distributed nanometer apertures are adopted to realize the sinusoidal reflectance. Typically, according to our physical design, the ERAQSZPs are fabricated on a bulk substrate;therefore, the new idea can significantly reduce the difficulty in the fabrication process. Based on the Kirchhoff diffraction theory and convolution theorem, the focusing performance of ERAQSZPs is calculated. The results reveal that apart from the capability of generating optical vortices,ERAQSZPs can also integrate the function of focusing, energy selection, higher-order foci elimination, as well as high spectral resolution together. In addition, the focusing properties can be further improved by appropriately adjusting the parameters, such as zone number and the size of the consisted primitives. These findings are expected to direct a new direction toward improving the performance of optical capture, x-ray fluorescence spectra, and forbidden transition. 展开更多
关键词 optical vortex single-focus spiral zone plate topological charges
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Moiré superlattices arising from growth induced by screw dislocations in layered materials
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作者 田伏钰 Muhammad Faizan +2 位作者 贺欣 孙远慧 张立军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期72-77,共6页
Moiré superlattices(MSLs) are modulated structures produced from homogeneous or heterogeneous two-dimensional layers stacked with a twist angle and/or lattice mismatch. Enriching the methods for fabricating MSL a... Moiré superlattices(MSLs) are modulated structures produced from homogeneous or heterogeneous two-dimensional layers stacked with a twist angle and/or lattice mismatch. Enriching the methods for fabricating MSL and realizing the unique emergent properties are key challenges in its investigation. Here we recommend that the spiral dislocation driven growth is another optional method for the preparation of high quality MSL samples. The spiral structure stabilizes the constant out-of-plane lattice distance, causing the variations in electronic and optical properties. Taking SnS_(2) MSL as an example, we find prominent properties including large band gap reduction(~ 0.4 e V) and enhanced optical activity. Firstprinciples calculations reveal that these unusual properties can be ascribed to the locally enhanced interlayer interaction associated with the Moiré potential modulation. We believe that the spiral dislocation driven growth would be a powerful method to expand the MSL family and broaden their scope of application. 展开更多
关键词 Moirésuperlattices interlayer interaction spiral dislocation layered materials
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Terahertz quasi-perfect vortex beam with integer-order and fractional-order generated by spiral spherical harmonic axicon
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作者 涂思语 刘德峰 +2 位作者 刘劲松 杨振刚 王可嘉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期458-467,共10页
We propose a new method to generate terahertz perfect vortex beam with integer-order and fractional-order. A new optical diffractive element composed of the phase combination of a spherical harmonic axicon and a spira... We propose a new method to generate terahertz perfect vortex beam with integer-order and fractional-order. A new optical diffractive element composed of the phase combination of a spherical harmonic axicon and a spiral phase plate is designed and called spiral spherical harmonic axicon. A terahertz Gaussian beam passes through the spiral spherical harmonic axicon to generate a terahertz vortex beam. When only the topological charge number carried by spiral spherical harmonic axicon increases, the ring radius of terahertz vortex beam increases slightly, so the beam is shaped into a terahertz quasi-perfect vortex beam. Importantly, the terahertz quasi-perfect vortex beam can carry not only integer-order topological charge number but also fractional-order topological charge number. This is the first time that vortex beam and quasi-perfect vortex beam with fractional-order have been successfully realized in terahertz domain and experiment. 展开更多
关键词 TERAHERTZ spiral spherical harmonic axicon quasi-perfect vortex beam topological charge number
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Low Surface Brightness Galaxies Selected by Different Model Fitting
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作者 Bing-Qing Zhang Hong Wu +3 位作者 Wei Du Pin-Song Zhao Min He Feng-Jie Lei 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期223-236,共14页
We present a study of low surface brightness galaxies(LSBGs) selected by fitting the images for all the galaxies inα.40 SDSS DR7 sample with two kinds of single-component models and two kinds of two-component models(... We present a study of low surface brightness galaxies(LSBGs) selected by fitting the images for all the galaxies inα.40 SDSS DR7 sample with two kinds of single-component models and two kinds of two-component models(disk+bulge):single exponential,single sersic,exponential+deVaucular(exp+deV),and exponential+sérsic(exp+ser).Under the criteria of the B band disk central surface brightness μ_(0,disk)(B)≥22.5 mag arcsec^(-2) and the axis ratio b/a> 0.3,we selected four none-edge-on LSBG samples from each of the models which contain 1105,1038,207,and 75 galaxies,respectively.There are 756 galaxies in common between LSBGs selected by exponential and sersic models,corresponding to 68.42% of LSBGs selected by the exponential model and 72.83% of LSBGs selected by the sersic model,the rest of the discrepancy is due to the difference in obtaining μ_(0) between the exponential and sersic models.Based on the fitting,in the range of 0.5≤n≤1.5,the relation of μ_(0) from two models can be written as μ_(0,sérsic)-μ_(0,exp)=-1.34(n-1).The LSBGs selected by disk+bulge models(LSBG_(2)comps) are more massive than LSBGs selected by single-component models(LSBG_1comp),and also show a larger disk component.Though the bulges in the majority of our LSBG_(2)comps are not prominent,more than 60% of our LSBG_(2)comps will not be selected if we adopt a single-component model only.We also identified 31 giant low surface brightness galaxies(gLSBGs) from LSBG_(2)comps.They are located at the same region in the color-magnitude diagram as other gLSBGs.After we compared different criteria of gLSBGs selection,we find that for gas-rich LSBGs,M_(*)> 10^(10)M_⊙ is the best to distinguish between gLSBGs and normal LSBGs with bulge. 展开更多
关键词 catalogs galaxies:spiral galaxies:bulges methods:data analysis methods:statistical
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Device-assisted enteroscopy: Are we ready to dismiss the spiral?
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作者 Alessandro Mussetto Elettra Merola +7 位作者 Cesare Casadei Daniele Salvi Fabiola Fornaroli Silvia Cocca Margherita Trebbi Armando Gabbrielli Cristiano Spada Andrea Michielan 《World Journal of Gastroenterology》 SCIE CAS 2024年第26期3185-3192,共8页
Motorized spiral enteroscopy(MSE)is the latest advance in device-assisted enteroscopy.Adverse events related to MSE were discussed in a recent large systematic review and meta-analysis and were directly compared with ... Motorized spiral enteroscopy(MSE)is the latest advance in device-assisted enteroscopy.Adverse events related to MSE were discussed in a recent large systematic review and meta-analysis and were directly compared with those of balloon enteroscopy in a case-matched study and a randomized controlled trial.Following the real-life application of MSE,an unexpected safety issue emerged regarding esophageal injury and the technique has been withdrawn from the global market,despite encouraging results in terms of diagnostic and therapeutic yield.We conducted an Italian multicenter real-life prospective study,which was prematurely terminated after the withdrawal of MSE from the market.The primary goals were the evaluation of MSE performance(both diagnostic and therapeutic)and its safety in routine endoscopic practice,particularly in the early phase of introduction in the endoscopic unit.A subanalysis,which involved patients who underwent MSE after unsuccessful balloon enteroscopy,demonstrated,for the first time,the promising performance of MSE as a rescue procedure.Given its remarkable performance in clinical practice and its potential role as a backup technique following a previously failed enteroscopy,it may be more appropriate to refine and enhance MSE in the future rather than completely abandoning it. 展开更多
关键词 Motorized spiral enteroscopy Rescue enteroscopy Diagnostic yield Adverse events AGREE classification
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An Asymmetric Galactic Stellar Disk Traced by OB-type Stars from LAMOST DR7
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作者 Xiaopeng Liu Hao Tian +4 位作者 Wenyuan Cui Linlin Li Jiaming Liu Zhenyan Huo Yawei Gao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期38-51,共14页
Using 9943 OB-type stars from LAMOST DR7 in the solar neighborhood,we fit the vertical stellar density profile with the model including a single exponential distribution at different positions(R,Φ).The distributions ... Using 9943 OB-type stars from LAMOST DR7 in the solar neighborhood,we fit the vertical stellar density profile with the model including a single exponential distribution at different positions(R,Φ).The distributions of the scale heights and scale length show that the young disk traced by the OB-type stars is not axisymmetric.The scale length decreases versus the azimuthal angleΦ,i.e.,from.■kpc withΦ=-3°to■kpc withΦ=9°.Meanwhile we find signal of non-symmetry in the distribution of the scale height of the north and south of the disk plane.The scale height in the north side shows signal of flaring of the disk,while that of the south disk stays almost constant around h_(s)=130 pc.The distribution of the displaceeent of the disk plane Z_(0)also shows variance versus the azimuthal angleΦ,which displays significant differences with the warp model constrained by the Cepheid stars.We also test different values for the position of the Sun,and the distance between the Sun and the Galactic center affects the scale heights and the displacement of the disk significantly,but that does not change our conclusion that the disk is not axisymmetric. 展开更多
关键词 Galaxy:disk galaxies:spiral stars:early-type stars:massive
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Four Late-type Galaxies with Double Radio Lobes and Properties of Such Galaxies
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作者 Z.S.Yuan X.Y.Gao +1 位作者 Z.L.Wen J.L.Han 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期84-90,共7页
The triggering mechanism for radio lobes from late-type galaxies is not fully understood.More samples are desired for a thorough investigation and statistics.By utilizing the optical data from the newly released Dark ... The triggering mechanism for radio lobes from late-type galaxies is not fully understood.More samples are desired for a thorough investigation and statistics.By utilizing the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four Late-type Galaxies with double Radio Lobes(La GRLs):J0217-3645,J0947+6220,J1412+3723 and J1736+5108.Including previously known La GRLs,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host galaxies.Most(25/35)La GRLs belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red sequence.We find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio lobes.Furthermore,the majority(31/36)of La GRLs are either located in a galaxy group or displaying a disturbed morphology.We suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies. 展开更多
关键词 galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies
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Morphological Classification of Infrared Galaxies Based on WISE
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作者 Zhi-Ren Pan Bo Qiu +3 位作者 Cui-Xiang Liu A-Li Luo Xia Jiang Xiao-Yu Guo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期222-236,共15页
This study introduces a novel convolutional neural network,the WISE Galaxy Classification Network(WGC),for classifying spiral and elliptical galaxies using Wide-field Infrared Survey Explorer(WISE)images.WGC attains a... This study introduces a novel convolutional neural network,the WISE Galaxy Classification Network(WGC),for classifying spiral and elliptical galaxies using Wide-field Infrared Survey Explorer(WISE)images.WGC attains an accuracy of 89.03%,surpassing the combined use of K-means or SVM with the Color-Color method in more accurately identifying galaxy morphologies.The enhanced variant,WGC_mag,integrates magnitude parameters with image features,further boosting the accuracy to 89.89%.The research also delves into the criteria for galaxy classification,discovering that WGC primarily categorizes dust-rich images as elliptical galaxies,corresponding to their lower star formation rates,and classifies less dusty images as spiral galaxies.The paper explores the consistency and complementarity of WISE infrared images with SDSS optical images in galaxy morphology classification.The SDSS Galaxy Classification Network(SGC),trained on SDSS images,achieved an accuracy of 94.64%.The accuracy reached 99.30% when predictions from SGC and WGC were consistent.Leveraging the complementarity of features in WISE and SDSS images,a novel variant of a classifier,namely the Multi-band Galaxy Morphology Integrated Classifier,has been developed.This classifier elevates the overall prediction accuracy to 95.39%.Lastly,the versatility of WGC was validated in other data sets.On the HyperLEDA data set,the distinction between elliptical galaxies and Sc,Scd and Sd spiral galaxies was most pronounced,achieving an accuracy of 90%,surpassing the classification results of the Galaxy Zoo 2 labeled WISE data set.This research not only demonstrates the effectiveness of WISE images in galaxy morphology classification but also represents an attempt to integrate multi-band astronomical data to enhance understanding of galaxy structures and evolution. 展开更多
关键词 methods:data analysis infrared:galaxies galaxies:spiral galaxies:elliptical and lenticular CD
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Fusion of Spiral Convolution-LSTM for Intrusion Detection Modeling
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作者 Fei Wang Zhen Dong 《Computers, Materials & Continua》 SCIE EI 2024年第5期2315-2329,共15页
Aiming at the problems of low accuracy and slow convergence speed of current intrusion detection models,SpiralConvolution is combined with Long Short-Term Memory Network to construct a new intrusion detection model.Th... Aiming at the problems of low accuracy and slow convergence speed of current intrusion detection models,SpiralConvolution is combined with Long Short-Term Memory Network to construct a new intrusion detection model.The dataset is first preprocessed using solo thermal encoding and normalization functions.Then the spiral convolution-Long Short-Term Memory Network model is constructed,which consists of spiral convolution,a two-layer long short-term memory network,and a classifier.It is shown through experiments that the model is characterized by high accuracy,small model computation,and fast convergence speed relative to previous deep learning models.The model uses a new neural network to achieve fast and accurate network traffic intrusion detection.The model in this paper achieves 0.9706 and 0.8432 accuracy rates on the NSL-KDD dataset and the UNSWNB-15 dataset under five classifications and ten classes,respectively. 展开更多
关键词 Intrusion detection deep learning spiral convolution long and short term memory networks 1D-spiral convolution
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Study on the Relationship between Structural Aspects and Aerodynamic Characteristics of Archimedes Spiral Wind Turbines
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作者 Yuanjun Dai Zetao Deng +2 位作者 Baohua Li Lei Zhong Jianping Wang 《Fluid Dynamics & Materials Processing》 EI 2024年第7期1517-1537,共21页
A combined experimental and numerical research study is conducted to investigate the complex relationship between the structure and the aerodynamic performances of an Archimedes spiral wind turbine(ASWT).Two ASWTs are... A combined experimental and numerical research study is conducted to investigate the complex relationship between the structure and the aerodynamic performances of an Archimedes spiral wind turbine(ASWT).Two ASWTs are considered,a prototypical version and an improved version.It is shown that the latter achieves the best aerodynamic performance when the spread angles at the three sets of blades areα_(1)=30°,α_(2)=55°,α3=60°,respectively and the blade thickness is 4 mm.For a velocity V=10 m/s,a tip speed ratio(TSR)=1.58 and 2,the maximum CP values are 0.223 and 0.263 for the prototypical ASWT and improved ASWT,respectively,and the maximum C_(P) enhancement is 17.93%.For V=10 m/s and TSR=2,the CP values of the prototypical ASWT and improved ASWT are 0.225 and 0.263,respectively,with an aerodynamic performance enhancement of 16.88%.Through mutual verification of the test outcomes and numerical results,it is concluded that the proposed approach can effectively lead to aerodynamic performance improvement. 展开更多
关键词 Archimedes spiral wind turbine aerodynamic performance numerical calculation
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Effectiveness of magnetic resonance imaging and spiral computed tomography in the staging and treatment prognosis of colorectal cancer
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作者 Lu-Na Bai Lu-Xian Zhang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2135-2144,共10页
BACKGROUND Colorectal cancer(CRC)is a prevalent cancer type in clinical settings;its early signs can be difficult to detect,which often results in late-stage diagnoses in many patients.The early detection and diagnosi... BACKGROUND Colorectal cancer(CRC)is a prevalent cancer type in clinical settings;its early signs can be difficult to detect,which often results in late-stage diagnoses in many patients.The early detection and diagnosis of CRC are crucial for improving treatment success and patient survival rates.Recently,imaging techniques have been hypothesized to be essential in managing CRC,with magnetic resonance imaging(MRI)and spiral computed tomography(SCT)playing a significant role in enhancing diagnostic and treatment approaches.AIM To explore the effectiveness of MRI and SCT in the preoperative staging of CRC and the prognosis of laparoscopic treatment.METHODS Ninety-five individuals admitted to Zhongshan Hospital Xiamen University underwent MRI and SCT and were diagnosed with CRC.The precision of MRI and SCT for the presurgical classification of CRC was assessed,and pathological staging was used as a reference.Receiver operating characteristic curves were used to evaluate the diagnostic efficacy of blood volume,blood flow,time to peak,permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction on the prognosis of patients with CRC.RESULTS Pathological biopsies confirmed the following CRC stages:23,23,32,and 17 at T1,T2,T3,and T4,respectively.There were 39 cases at the N0 stage,22 at N1,34 at N2,44 at M0 stage,and 51 at M1.Using pathological findings as the benchmark,the combined use of MRI and SCT for preoperative TNM staging in patients with CRC demonstrated superior sensitivity,specificity,and accuracy compared with either modality alone,with a statistically significant difference in accuracy(P<0.05).Receiver operating characteristic curve analysis revealed the predictive values for laparoscopic treatment prognosis,as indicated by the areas under the curve for blood volume,blood flow,time to peak,and permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction were 0.750,0.683,0.772,0.761,0.709,0.719,and 0.910,respectively.The corresponding sensitivity and specificity values were also obtained(P<0.05).CONCLUSION MRI with SCT is effective in the clinical diagnosis of patients with CRC and is worthy of clinical promotion. 展开更多
关键词 Magnetic resonance imaging Spiral computed tomography Colorectal cancer PROGNOSIS Receiver operating characteristic curve Retrospective study
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The GBR Hypothesis Revisited
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作者 Lewis Nash 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期800-809,共10页
The radical hypothesis concerning the physics of gravitational black-body radiation is placed on a more solid statistical mechanics foundation in this study. As the concepts and formalism in the former presentation ar... The radical hypothesis concerning the physics of gravitational black-body radiation is placed on a more solid statistical mechanics foundation in this study. As the concepts and formalism in the former presentation are only partially developed and furthermore, suffer from an unfortunate misstep regarding Hawking radiation and the hypothetical gravitational black-body temperature of a parcel or distribution of energy;this paper aims to fill in some of the theoretical gaps in the derivation of the Planck radiation formula for gravity (or non-Euclidean space-time), and there by provide a more complete and transparent quantum theory of thermal gravitational radiation. 展开更多
关键词 Gravitational Black Body GRAVITONS Thermal Gravitational Radiation Spiral Galaxy Rotation Curves
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Measurements of the Dark Matter Mass, Temperature and Spin
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作者 Bruce Hoeneisen 《International Journal of Astronomy and Astrophysics》 2024年第3期184-202,共19页
We summarize several measurements of the dark matter temperature-to-mass ratio, or equivalently, of the comoving root-mean-square thermal velocity of warm dark matter particles vhrms(1). The most reliable determinatio... We summarize several measurements of the dark matter temperature-to-mass ratio, or equivalently, of the comoving root-mean-square thermal velocity of warm dark matter particles vhrms(1). The most reliable determination of this parameter comes from well measured rotation curves of dwarf galaxies by the LITTLE THINGS collaboration: vhrms(1)=406±69 m/s. Complementary and consistent measurements are obtained from rotation curves of spiral galaxies measured by the SPARC collaboration, density runs of giant elliptical galaxies, galaxy ultra-violet luminosity distributions, galaxy stellar mass distributions, first galaxies, and reionization. Having measured vhrms(1), we then embark on a journey to the past that leads to a consistent set of measured dark matter properties, including mass, temperature and spin. 展开更多
关键词 Warm Dark Matter Dwarf Galaxies Spiral Galaxies Elliptical Galaxies Galaxy Distributions First Galaxies REIONIZATION
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The Role of MSCT in Evaluating Tumor Size,Density,Immunohistochemical Classification,and Pathological Risk in GIST Patients
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作者 Yi Luo Jiaman Li +4 位作者 Pengman Chen Junmao Huang Shuisheng Yi Xinliang Chen Zhenfeng Wen 《Proceedings of Anticancer Research》 2024年第5期182-188,共7页
Objective:To investigate the role of multilayer spiral CT(MSCT)in evaluating patients with gastrointestinal stromal tumors(GIST),particularly its utility in determining tumor size,immunohistochemical classification,an... Objective:To investigate the role of multilayer spiral CT(MSCT)in evaluating patients with gastrointestinal stromal tumors(GIST),particularly its utility in determining tumor size,immunohistochemical classification,and pathological risk.Methods:A retrospective analysis was conducted on 22 GIST patients,confirmed by surgical pathology between January 2019 and December 2023.All patients underwent MSCT examination prior to surgery.Tumor size,density,and immunohistochemical classification from the MSCT results were compared with the postoperative pathological findings.Additionally,the ability of MSCT to predict GIST risk grade was evaluated in combination with immunohistochemical analysis results.Results:No significant differences were found between the preoperative MSCT findings and postoperative pathological results in terms of tumor size,density,or immunohistochemical classification in GIST patients.MSCT also enhanced the ability to predict GIST risk grades.Conclusion:MSCT demonstrates significant clinical value in the diagnosis and risk assessment of GIST,aiding in the prediction of the tumor’s biological behavior and patients’treatment responses. 展开更多
关键词 Gastrointestinal stromal tumor Multilayer spiral CT Tumor size IMMUNOHISTOCHEMISTRY Pathological risk
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Improved Arithmetic Optimization Algorithm with Multi-Strategy Fusion Mechanism and Its Application in Engineering Design
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作者 Yu Liu Minge Chen +3 位作者 Ran Yin Jianwei Li Yafei Zhao Xiaohua Zhang 《Journal of Applied Mathematics and Physics》 2024年第6期2212-2253,共42页
This article addresses the issues of falling into local optima and insufficient exploration capability in the Arithmetic Optimization Algorithm (AOA), proposing an improved Arithmetic Optimization Algorithm with a mul... This article addresses the issues of falling into local optima and insufficient exploration capability in the Arithmetic Optimization Algorithm (AOA), proposing an improved Arithmetic Optimization Algorithm with a multi-strategy mechanism (BSFAOA). This algorithm introduces three strategies within the standard AOA framework: an adaptive balance factor SMOA based on sine functions, a search strategy combining Spiral Search and Brownian Motion, and a hybrid perturbation strategy based on Whale Fall Mechanism and Polynomial Differential Learning. The BSFAOA algorithm is analyzed in depth on the well-known 23 benchmark functions, CEC2019 test functions, and four real optimization problems. The experimental results demonstrate that the BSFAOA algorithm can better balance the exploration and exploitation capabilities, significantly enhancing the stability, convergence mode, and search efficiency of the AOA algorithm. 展开更多
关键词 Arithmetic Optimization Algorithm Adaptive Balance Factor Spiral Search Brownian Motion Whale Fall Mechanism
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Dark Matter Density Profiles of Selected Spiral Galaxies
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作者 Alberto Sadun Brittany Salmon +1 位作者 Conor Evans Masoud Asadi-Zeydabadi 《International Journal of Astronomy and Astrophysics》 2024年第3期172-183,共12页
Understanding the dark matter distribution throughout a galaxy can provide insight into its elusive nature. Numerous density profiles, such as the Navarro, Frenk and White model, have been created in an attempt to stu... Understanding the dark matter distribution throughout a galaxy can provide insight into its elusive nature. Numerous density profiles, such as the Navarro, Frenk and White model, have been created in an attempt to study this distribution through analyzing orbital velocities of luminous matter and modeling dark matter distributions to explain these observations. However, we are interested in a simple model to consider the significant fluctuations in rotation curves at larger radii. Therefore, our model is much simpler compared to those previously mentioned. Our model used all the observational data available for four selected galactic rotation curves. These data present a significant variation in the orbital velocity of matter at the same distances. By running real observational data through our model, we show that the density of the dark matter within them shows real complex structure, which is not suggested by other computational models. Our aim of this paper is to model this structure and then speculate as to the cause and implications of these density fluctuations. 展开更多
关键词 Dark Matter Density Galactic Rotation Curves Spiral Galaxies NGC 2841 NGC 4527 NGC 4945 NGC 3198
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The Origin of the Flat Rotation Curves in Spiral Galaxies: The Hidden Roles of Glitching SMDEOs and Emission of Gravitational Waves
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作者 Ahmad A. Hujeirat Peter Berczik 《Journal of Modern Physics》 2024年第10期1523-1542,共20页
Supermassive DEOs (SMDEOs) are cosmologically evolved objects made of irreducible incompressible supranuclear dense superfluids: The state we consider to govern the matter inside the cores of massive neutron stars. Th... Supermassive DEOs (SMDEOs) are cosmologically evolved objects made of irreducible incompressible supranuclear dense superfluids: The state we consider to govern the matter inside the cores of massive neutron stars. These cores are practically trapped in false vacua, rendering their detection by outside observers impossible. Based on massive parallel computations and theoretical investigations, we show that SMDEOs at the centres of spiral galaxies that are surrounded by massive rotating torii of normal matter may serve as powerful sources for gravitational waves carrying away roughly 1042 erg/s. Due to the extensive cooling by GWs, the SMDEO-Torus systems undergo glitching, through which both rotational and gravitational energies are abruptly ejected into the ambient media, during which the topologies of the embedding spacetimes change from curved into flatter ones, thereby triggering a burst gravitational energy of order 1059 erg. Also, the effects of glitches found to alter the force balance of objects in the Lagrangian-L1 region between the central SMDEO-Torus system and the bulge, enforcing the enclosed objects to develop violent motions, that may explain the origin of the rotational curve irregularities observed in the innermost part of spiral galaxies. Our study shows that the generated GWs at the centres of galaxies, which traverse billions of objects during their outward propagations throughout the entire galaxy, lose energy due to repeatedly squeezing and stretching the objects. Here, we find that these interactions may serve as damping processes that give rise to the formation of collective forces f∝m(r)/r, that point outward, endowing the objects with the observed flat rotation curves. Our approach predicts a correlation between the baryonic mass and the rotation velocities in galaxies, which is in line with the Tully-Fisher relation. The here-presented self-consistent approach explains nicely the observed rotation curves without invoking dark matter or modifying Newtonian gravitation in the low-field approximation. 展开更多
关键词 General Relativity: Black Holes Neutron Stars Quantum Fields: QCD Condensed Matter INCOMPRESSIBILITY SUPERFLUIDITY Cosmology: Galaxy Formation Spiral Galaxies Dark Matter Rotation Curves
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