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Multi-Scale Dilated Convolution Network for SPECT-MPI Cardiovascular Disease Classification with Adaptive Denoising and Attenuation Correction
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作者 A.Robert Singh Suganya Athisayamani +1 位作者 Gyanendra Prasad Joshi Bhanu Shrestha 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期299-327,共29页
Myocardial perfusion imaging(MPI),which uses single-photon emission computed tomography(SPECT),is a well-known estimating tool for medical diagnosis,employing the classification of images to show situations in coronar... Myocardial perfusion imaging(MPI),which uses single-photon emission computed tomography(SPECT),is a well-known estimating tool for medical diagnosis,employing the classification of images to show situations in coronary artery disease(CAD).The automatic classification of SPECT images for different techniques has achieved near-optimal accuracy when using convolutional neural networks(CNNs).This paper uses a SPECT classification framework with three steps:1)Image denoising,2)Attenuation correction,and 3)Image classification.Image denoising is done by a U-Net architecture that ensures effective image denoising.Attenuation correction is implemented by a convolution neural network model that can remove the attenuation that affects the feature extraction process of classification.Finally,a novel multi-scale diluted convolution(MSDC)network is proposed.It merges the features extracted in different scales and makes the model learn the features more efficiently.Three scales of filters with size 3×3 are used to extract features.All three steps are compared with state-of-the-art methods.The proposed denoising architecture ensures a high-quality image with the highest peak signal-to-noise ratio(PSNR)value of 39.7.The proposed classification method is compared with the five different CNN models,and the proposed method ensures better classification with an accuracy of 96%,precision of 87%,sensitivity of 87%,specificity of 89%,and F1-score of 87%.To demonstrate the importance of preprocessing,the classification model was analyzed without denoising and attenuation correction. 展开更多
关键词 SPECT-MPI CAD MSDC DENOISING attenuation correction classification
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Transient elastography with controlled attenuation parameter for the diagnosis of colorectal polyps in patients with nonalcoholic fatty liver disease 被引量:1
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作者 Lan Wang Yan-Fei Li Li-Feng Dong 《World Journal of Clinical Cases》 SCIE 2024年第12期2050-2055,共6页
BACKGROUND The severity of nonalcoholic fatty liver disease(NAFLD)and lipid metabolism are related to the occurrence of colorectal polyps.Liver-controlled attenuation parameters(liver-CAPs)have been established to pre... BACKGROUND The severity of nonalcoholic fatty liver disease(NAFLD)and lipid metabolism are related to the occurrence of colorectal polyps.Liver-controlled attenuation parameters(liver-CAPs)have been established to predict the prognosis of hepatic steatosis patients.AIM To explore the risk factors associated with colorectal polyps in patients with NAFLD by analyzing liver-CAPs and establishing a diagnostic model.METHODS Patients who were diagnosed with colorectal polyps in the Department of Gastroenterology of our hospital between June 2021 and April 2022 composed the case group,and those with no important abnormalities composed the control group.The area under the receiver operating characteristic curve was used to predict the diagnostic efficiency.Differences were considered statistically significant when P<0.05.RESULTS The median triglyceride(TG)and liver-CAP in the case group were significantly greater than those in the control group(mmol/L,1.74 vs 1.05;dB/m,282 vs 254,P<0.05).TG and liver-CAP were found to be independent risk factors for colorectal polyps,with ORs of 2.338(95%CI:1.154–4.733)and 1.019(95%CI:1.006–1.033),respectively(P<0.05).And there was no difference in the diagnostic efficacy between liver-CAP and TG combined with liver-CAP(TG+CAP)(P>0.05).When the liver-CAP was greater than 291 dB/m,colorectal polyps were more likely to occur.CONCLUSION The levels of TG and liver-CAP in patients with colorectal polyps are significantly greater than those patients without polyps.Liver-CAP alone can be used to diagnose NAFLD with colorectal polyps. 展开更多
关键词 Colorectal polyps Nonalcoholic fatty liver disease Liver-controlled attenuation parameter Liver fibroscan Diagnostic model
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In-situ deposited anti-aging TiN capping layer for Nb superconducting quantum circuits
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作者 Hao-Ran Tao Lei Du +8 位作者 Liang-Liang Guo Yong Chen Hai-Feng Zhang Xiao-Yan Yang Guo-Liang Xu Chi Zhang Zhi-Long Jia Peng Duan Guo-Ping Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期133-137,共5页
The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal–air interface,where Nb2O5 is considered the main loss source.Here,we suppress the formation of native oxi... The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal–air interface,where Nb2O5 is considered the main loss source.Here,we suppress the formation of native oxides by in-situ deposition of a TiN capping layer on the Nb film.With TiN capping layers,no Nb2O5 forms on the surface of the Nb film.The quality factor Qi of the Nb resonator increases from 5.6×10^(5) to 7.9×10^(5) at low input power and from 6.8×10^(6) to 1.1×10^(7)at high input power.Furthermore,the TiN capping layer also shows good aging resistance in Nb resonator devices,with no significant performance fluctuations after one month of aging.These findings highlight the effectiveness of TiN capping layers in enhancing the performance and longevity of Nb superconducting quantum devices. 展开更多
关键词 anti-aging oxidation dielectric loss Nb superconducting quantum circuits
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Intrinsic and scattering attenuations of the Sichuan-Yunnan region in China from S coda waves
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作者 Tian Li Lei Zhang +4 位作者 Xiaodong Song Qincai Wang Xinyu Jiang Jinchuan Zhang Hanlin Chen 《Earthquake Science》 2024年第1期51-66,共16页
Seismic attenuation is a fundamental property of the Earth's media.Attenuation structure for the complicated geological structures with strong seismicity in the Sichuan-Yunnan region is poorly studied.In this stud... Seismic attenuation is a fundamental property of the Earth's media.Attenuation structure for the complicated geological structures with strong seismicity in the Sichuan-Yunnan region is poorly studied.In this study,we collected 108,399 waveforms of 11,517 local small earthquakes with magnitudes between 1.5 and 3.5 from January 2014 to September 2021 in the Sichuan-Yunnan region and its adjacent areas.We employed an envelope inversion technique for separating the intrinsic and scattering attenuations of the S coda wave,and obtained the intrinsic and scattering attenuation structures for frequencies between 0.25 and 8.00 Hz.The attenuation structures correlate well with the geological units,and some major faults mark the attenuation variations where historic large earthquakes have occurred.The regional average attenuation shows a negative frequency dependence.The average scattering attenuation has a faster descending rate than the average intrinsic attenuation,and is dominant at low frequencies,while at high frequencies the average intrinsic attenuation is stronger.The lateral variation in the intrinsic attenuation is consistent with the variation in heat flow,the scattering attenuation may be related to the scatter distribution and size.The total attenuation is consistent with the previous studies in this region,and the separate intrinsic and scattering attenuation may be useful in understanding regional tectonics and important in earthquake prevention and disaster reduction. 展开更多
关键词 Intrinsic attenuation scattering attenuation Sichuan-Yunnan region
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Anti-aging performance improvement and enhanced combustion efficiency of boron via the coating of PDA
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作者 Shuai Ma Qinghai Shu +4 位作者 Mengyang Zhang Hongyu Huang Yansong Shi Xijuan Lv Shuai Zhao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期399-410,共12页
Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during storage.The polydopamine(PDA)was introduced in... Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during storage.The polydopamine(PDA)was introduced into boron particles,investigating the impact of PDA content on the energetic behavior of boron.The results indicated that the PDA coating formed a fishing net structure on the surface of boron particles.The heat release results showed that the combustion calorific value of B@PDA was higher than that of the raw boron.Specifically,the actual combustion heat of boron powder in B@10%PDA increased by 38.08%.Meanwhile,the DSC peak temperature decreased by 100.65℃under similar oxidation rate compared to raw boron.Simultaneously,the B@PDA@AP and B@AP composites were prepared,and their combustion properties were evaluated.It was demonstrated that B@10%PDA@AP exhibited superior performance in terms of peak pressure and burning time,respectively.The peak pressure is 12.43 kPa more than B@AP and burning time is 2.22 times higher than B@AP.Therefore,the coating of PDA effectively inhibits the oxidization of boron during storage and enhances the energetic behavior of boron and corresponding composites. 展开更多
关键词 Boron particles POLYDOPAMINE anti-aging performance improvement Heat release
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A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures
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作者 Yan-Xiao He Shang-Xu Wang +9 位作者 Gen-Yang Tang Chao Sun Hong-Bing Li San-Yi Yuan Xian Wei Li-Deng Gan Xiao-Feng Dai Qiang Ge Peng-Peng Wei Hui-Qing Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期162-181,共20页
Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and... Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure conditions.Calibration with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2000,10^(6)]Hz.The Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent effects.Under dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the sandstone.In particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective pressure.In addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion. 展开更多
关键词 Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow
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Multiple Matching Attenuation Based on Curvelet Domain Extended Filtering
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作者 HUA Qingfeng CHEN Zhang +6 位作者 HE Huili TAN Jun CHEN Haifeng LI Guanbao SONG Peng ZHAO Bo JIANG Xiuping 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期924-932,共9页
The paper develops a multiple matching attenuation method based on extended filtering in the curvelet domain,which combines the traditional Wiener filtering method with the matching attenuation method in curvelet doma... The paper develops a multiple matching attenuation method based on extended filtering in the curvelet domain,which combines the traditional Wiener filtering method with the matching attenuation method in curvelet domain.Firstly,the method uses the predicted multiple data to generate the Hilbert transform records,time derivative records and time derivative records of Hilbert transform.Then,the above records are transformed into the curvelet domain and multiple matching attenuation based on least squares extended filtering is performed.Finally,the attenuation results are transformed back into the time-space domain.Tests on the model data and field data show that the method proposed in the paper effectively suppress the multiples while preserving the primaries well.Furthermore,it has higher accuracy in eliminating multiple reflections,which is more suitable for the multiple attenuation tasks in the areas with complex structures compared to the time-space domain extended filtering method and the conventional curvelet transform method. 展开更多
关键词 multiple matching attenuation curvelet domain extended filtering
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Layered metastructure containing freely-designed local resonators for wave attenuation
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作者 Yu Li Huguang He +3 位作者 Jiang Feng Hailong Chen Fengnian Jin Hualin Fan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期23-31,共9页
Combining periodic layered structure with three-dimensional cylindrical local resonators,a hybrid metastructure with improved wave isolation ability was designed and investigated through theoretical and numerical appr... Combining periodic layered structure with three-dimensional cylindrical local resonators,a hybrid metastructure with improved wave isolation ability was designed and investigated through theoretical and numerical approaches.The metastructure is composed of periodic rubber layers and concrete layers embedded with three-dimensional resonators,which can be freely designed with multi local resonant frequencies to attenuate vibrations at required frequencies and widen the attenuation bandgap.The metastructure can also effectively attenuate seismic responses.Compared with layered rubber-based structures,the metastructure has more excellent wave attenuation effects with greater attenuation and wider bandgap. 展开更多
关键词 Layered metastructure Local resonator Wave attenuation
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Application of sparse S transform network with knowledge distillation in seismic attenuation delineation
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作者 Nai-Hao Liu Yu-Xin Zhang +3 位作者 Yang Yang Rong-Chang Liu Jing-Huai Gao Nan Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2345-2355,共11页
Time-frequency analysis is a successfully used tool for analyzing the local features of seismic data.However,it suffers from several inevitable limitations,such as the restricted time-frequency resolution,the difficul... Time-frequency analysis is a successfully used tool for analyzing the local features of seismic data.However,it suffers from several inevitable limitations,such as the restricted time-frequency resolution,the difficulty in selecting parameters,and the low computational efficiency.Inspired by deep learning,we suggest a deep learning-based workflow for seismic time-frequency analysis.The sparse S transform network(SSTNet)is first built to map the relationship between synthetic traces and sparse S transform spectra,which can be easily pre-trained by using synthetic traces and training labels.Next,we introduce knowledge distillation(KD)based transfer learning to re-train SSTNet by using a field data set without training labels,which is named the sparse S transform network with knowledge distillation(KD-SSTNet).In this way,we can effectively calculate the sparse time-frequency spectra of field data and avoid the use of field training labels.To test the availability of the suggested KD-SSTNet,we apply it to field data to estimate seismic attenuation for reservoir characterization and make detailed comparisons with the traditional time-frequency analysis methods. 展开更多
关键词 S transform Deep learning Knowledge distillation Transfer learning Seismic attenuation delineation
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CT Thresholds for Spinal Bone Mineral Attenuation to Prioritize Eligible Older Women for Osteoporosis Screening
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作者 Seo Yeon K. Orite Bryn Higuchi +1 位作者 Hyo-Chun Yoon Lana H. Gimber 《Open Journal of Radiology》 2024年第2期92-101,共10页
Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone min... Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone mineral attenuation as measured in the L1 vertebra of CT studies to the results of dual-energy x-ray absorptiometry (DEXA) studies to determine what CT attenuation thresholds might yield a reasonable combination of sensitivity and specificity for the detection of osteoporosis. The study was limited to women between the ages of 65 and 75 years who had a DEXA study and a CT that included the L1 or adjacent vertebra performed within 3 years of the DEXA study. Results: There were 1226 women in this study, of whom 452 (38%) had osteoporosis based on a T-score ≤ −2.5 by DEXA. There were 830 CT studies performed with contrast and 396 studies which were performed without contrast. There was a statistically significant difference in the mean HU of those studies performed without contrast compared to those with contrast (unenhanced mean 103 HU versus 125 HU, p < 0.001). Different CT attenuation thresholds provided the most appropriate combination of sensitivity and specificity for the detection of osteoporosis when comparing CT studies performed without or with IV contrast and when all the CT data were used in aggregate. Conclusion: Different thresholds appear necessary when using the mean CT vertebral attenuation to identify older women for preferential referral for DEXA studies. 展开更多
关键词 OSTEOPOROSIS Bone Mineral attenuation CT Threshold
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Analytical modeling of piezoelectric meta-beams with unidirectional circuit for broadband vibration attenuation
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作者 Jiawei MAO Hao GAO +2 位作者 Junzhe ZHU Penglin GAO Yegao QU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第10期1665-1684,共20页
Broadband vibration attenuation is a challenging task in engineering since it is difficult to achieve low-frequency and broadband vibration control simultaneously.To solve this problem,this paper designs a piezoelectr... Broadband vibration attenuation is a challenging task in engineering since it is difficult to achieve low-frequency and broadband vibration control simultaneously.To solve this problem,this paper designs a piezoelectric meta-beam with unidirectional electric circuits,exhibiting promising broadband attenuation capabilities.An analytical model in a closed form for achieving the solution of unidirectional vibration transmission of the designed meta-beam is developed based on the state-space transfer function method.The method can analyze the forward and backward vibration transmission of the piezoelectric meta-beam in a unified manner,providing reliable dynamics solutions of the beam.The analytical results indicate that the meta-beam effectively reduces the unidirectional vibration across a broad low-frequency range,which is also verified by the solutions obtained from finite element analyses.The designed meta-beam and the proposed analytical method facilitate a comprehensive investigation into the distinctive unidirectional transmission behavior and superb broadband vibration attenuation performance. 展开更多
关键词 broadband vibration attenuation efficient closed-form analytical solution electromechanical coupling piezoelectric material vibration control
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Wave Attenuation and Turbulence Driven by Submerged Vegetation Under Current-Wave Flow
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作者 HUANG Yu-ming Ding Lei +3 位作者 WANG Yi-fei CHEN Ben YANG Xiao-yu DOU Xi-ping 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期602-611,共10页
A set of laboratory experiments are carried out to investigate the effect of following/opposing currents on wave attenuation.Rigid vegetation canopies with aligned and staggered configurations were tested under the co... A set of laboratory experiments are carried out to investigate the effect of following/opposing currents on wave attenuation.Rigid vegetation canopies with aligned and staggered configurations were tested under the condition of various regular wave heights and current velocities,with the constant water depth being 0.60 m to create the desired submerged scenarios.Results show that the vegetation-induced wave dissipation is enhanced with the increasing incident wave height.A larger velocity magnititude leads to a greater wave height attenuation for both following and opposing current conditions.Moreover,there is a strong positive linear correlation between the damping coefficientβand the relative wave height H_(0)/h,especially for pure wave conditions.For the velocity profile,the distributions of U_(min)and U_(max)show different patterns under combined wave and current.The time-averaged turbulent kinetic energy(TKE)vary little under pure wave and U_(c)=±0.05 m/s conditions.With the increase of flow velocity amplitude,the time-averaged TKE shows a particularly pronounced increase trend at the top of the canopy.The vegetation drag coefficients are obtained by a calibration approach.The empirical relations of drag coefficient with Reynolds and Keulegane-Carpenter numbers are proposed to further understand the wave-current-vegetation interaction mechanism. 展开更多
关键词 wave attenuation rigid vegetation following and opposing currents turbulent kinetic energy
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P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures
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作者 Sheng-Qing Li Wen-Hao Wang +2 位作者 Yuan-Da Su Jun-Xin Guo Xiao-Ming Tang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期143-161,共19页
P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned fractures.However,there are few existing models that incorporate the multiple wave attenuation me... P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned fractures.However,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic scale.Hence,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the fractures.Using Tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and SV-waves.We then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy approximation.The results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave velocities.The coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV waves.Randomly oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV waves.Through a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model. 展开更多
关键词 Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow
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Characterization of three African swine fever viruses from diferent clinical settings revealed a potential attenuation mechanism
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作者 Jiajia Zhang Yuening Wang +8 位作者 Kaili Zhang Dafu Deng Kai Peng Wanglong Zheng Nanhua Chen Penggang Liu Shaobin Shang Ruichao Li Jianzhong Zhu 《Animal Diseases》 CAS 2024年第4期263-274,共12页
African swine fever(ASF)is an acute and fatal hemorrhagic disease in domestic pigs and wild boars caused by African swine fever virus(ASFV)that currently threatens the pig industry worldwide.Since the 2018 ASF outbrea... African swine fever(ASF)is an acute and fatal hemorrhagic disease in domestic pigs and wild boars caused by African swine fever virus(ASFV)that currently threatens the pig industry worldwide.Since the 2018 ASF outbreak in China,ASFV has evolved and caused diverse clinical manifestations,such as chronic and asymptomatic infections.Therefore,it is important to understand the molecular mechanisms underlying ASFV attenuation in the feld.Here,we isolated three ASFVs from one diseased and two asymptomatic pigs by using primary porcine alveolar macrophages(PAMs)from both domestic pigs and Bama minipigs.The three ASFVs exhibited similar phenotypes in cell culture,includ‑ing cytopathic efects(CPEs),hemadsorptions(HADs),viral protein expressions and growth curves.Genome sequenc‑ing revealed that all three ASFVs were genotype II strains.Genomic comparisons suggested that the disruption of the viral genes MGF360 and MGF110,rather than EP402R and EP153R,is likely involved in the potential attenuation of ASFV via the upregulation of innate immune responses. 展开更多
关键词 African swine fever virus Virus isolation Genome sequence Genotype II attenuation
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Fuzzy Multi-Criteria Decision Support System for the Best Anti-Aging Treatment Selection Process through Normal Wiggly Hesitant Fuzzy Sets
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作者 Daekook Kang Ramya Lakshmanaraj +5 位作者 Samayan Narayanamoorthy Navaneethakrishnan Suganthi Keerthana Devi Samayan Kalaiselvan Ranganathan Saraswathy Dragan Pamucar Vladimir Simic 《Computers, Materials & Continua》 SCIE EI 2024年第9期4947-4972,共26页
This socialized environment among educated and developed people causes themto focusmore on their appearance and health,which turns them towards medical-related treatments,leading us to discuss anti-aging treatment met... This socialized environment among educated and developed people causes themto focusmore on their appearance and health,which turns them towards medical-related treatments,leading us to discuss anti-aging treatment methods for each age group,particularly for urban people who are interested in this.Some anti-aging therapies are used to address the alterations brought on by aging in human life without the need for surgery or negative effects.Five anti-aging therapies such as microdermabrasion or dermabrasion,laser resurfacing anti-aging skin treatments,chemical peels,dermal fillers for aged skin,and botox injections are considered in this study.Based on the criteria of safety risk,investment cost,customer happiness,and side effects,the optimal alternative is picked.As a result,a NormalWiggly Hesitant Pythagorean Fuzzy Set(NWHPFS)is constructed and used in Multi-Criteria Decision-Making(MCDM)using traditional wavy mathematical approaches.The entropy approach is utilized to determine weight values,and the Normal Wiggly Hesitant Pythagorean-VlseKriterijumska Optimizacija I Kompromisno Resenje(NWHPF-VIKOR)method is utilized to rank alternatives using MCDM methodologies.Sensitivity analysis and comparative analysis were performed to ensure the robustness and reliability of the proposed method.The smart final choice will undoubtedly assist Decision Makers(DM)in making the right judgments,and the MCDM approach will undoubtedly assist individuals in understanding the medicine. 展开更多
关键词 Normal wiggly hesitant pythagorean fuzzy set hesitant pythagorean fuzzy set anti-aging treatment entropy VIse Kriterijumska Optimizacija I Kompromisno Resenje
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Anti-aging based on stem cell therapy:A scoping review
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作者 Nassar El Assaad Alain Chebly +8 位作者 Rawad Salame Robert Achkar Nour Bou Atme Khalil Akouch Paul Rafoul Colette Hanna Samer Abou Zeid Marwan Ghosn Charbel Khalil 《World Journal of Experimental Medicine》 2024年第3期57-63,共7页
Stem cells are present in the tissues and organs and remain in a quiescent and undifferentiated state until it is physiologically necessary to produce new descendant cells.Due to their multipotency property,mesenchyma... Stem cells are present in the tissues and organs and remain in a quiescent and undifferentiated state until it is physiologically necessary to produce new descendant cells.Due to their multipotency property,mesenchymal stem cells have attracted considerable attention worldwide due to their immunomodulation and therapeutic function in tissue regeneration.Stem cells secrete components such as paracrine factors,extracellular vesicles,and exosomes which have been shown to have anti-inflammatory,anti-aging,reconstruction and wound healing potentials in many in vitro and in vivo models.The pluripotency and immunomodulatory features of stem cells could potentially be an effective tool in cell therapy and tissue repair.Aging affects the capacity for self-renewal and differentiation of stem cells,decreasing the potential for regeneration and the loss of optimal functions in organisms over time.Current progress in the field of cellular therapy and regenerative medicine has facilitated the evolution of particular guidelines and quality control approaches,which eventually lead to clinical trials.Cell therapy could potentially be one of the most promising therapies to control aging due to the fact that single stem cell transplantation can regenerate or substitute the injured tissue.To understand the involvement of stem cells not only in tissue maintenance and disease but also in the control of aging it is important to know and identify their properties,functions,and regulation in vivo,which are addressed in this review. 展开更多
关键词 Mesenchymal stem cell anti-aging TELOMERASE Regenerative medicine Stem cell therapy
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Application of plant extracts cosmetics in the field of anti-aging
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作者 Minghui Xie Zibing Jiang +1 位作者 Xingyue Lin Xingchuan Wei 《Journal of Dermatologic Science and Cosmetic Technology》 2024年第2期53-62,共10页
Skin aging is a direct manifestation of body aging,representing a complex and irreversible natural process,which is influenced by genetics,lifestyle and environmental factors.In the process of skin aging,the skin epid... Skin aging is a direct manifestation of body aging,representing a complex and irreversible natural process,which is influenced by genetics,lifestyle and environmental factors.In the process of skin aging,the skin epidermis gradually become thinner,the inherent repair ability gradually weakens,the collagen and elastin gradually decrease and the skin gradually loses elasticity.Although skin aging is inevitable,it can be delayed to some extent by using cosmetics.Natural extract cosmetics are highly favored by consumers for their safety and efficacy,aligning with consumer preferences for natural,organic,efficient and sustainable skincare concepts.Numerous plant resources in nature possess superior properties like moisturizing,barrier repair,anti-oxidation,sunscreen whitening and anti-inflammatory properties after thousands of years of natural selection.These properties enable plant components to effectively enhance the anti-aging effects of skincare products through multiple anti-aging pathways,which can be widely used to develop natural anti-aging skin care products. 展开更多
关键词 Plant resources anti-aging Green Efficacy skin care COSMETICS
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High-precision frequency attenuation analysis and its application 被引量:9
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作者 熊晓军 贺锡雷 +2 位作者 蒲勇 贺振华 林凯 《Applied Geophysics》 SCIE CSCD 2011年第4期337-343,372,共8页
Based on seismic attenuation theory in a fluid-filled porous medium, we improve conventional methods of low-frequency shadow analysis (LFSA) and energy absorption analysis (EAA) and propose a high-precision freque... Based on seismic attenuation theory in a fluid-filled porous medium, we improve conventional methods of low-frequency shadow analysis (LFSA) and energy absorption analysis (EAA) and propose a high-precision frequency attenuation analysis technology. First, we introduce the method of three-parameter wavelet transform and the time-frequency focused criterion and develop a high-precision time-frequency analysis method based on an adaptive three-parameter wavelet transform, which has high time-frequency resolution with benefit to LFSA and can obtain a single-peaked spectrum with narrow side-lobes with benefit to EAA. Second, we correctly compute absorption coefficient by curve fitting based on the nonlinear Nelder-Mead algorithm and effectively improve EAA precision. Practical application results show that the proposed frequency attenuation analysis technology integrated with LFSA and EAA can effectively predict favorable zones of carbonate oolitic reservoir. Furthermore, reservoir prediction results based on LFSA correspond with EAA. The new technology can effectively improve reservoir prediction reliability and reduce exploration risk. 展开更多
关键词 attenuation analysis low-frequency shadow energy absorption analysis time- frequency analysis
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An iterative curvelet thresholding algorithm for seismic random noise attenuation 被引量:9
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作者 王德利 仝中飞 +1 位作者 唐晨 朱恒 《Applied Geophysics》 SCIE CSCD 2010年第4期315-324,399,共11页
In this paper,we explore the use of iterative curvelet thresholding for seismic random noise attenuation.A new method for combining the curvelet transform with iterative thresholding to suppress random noise is demons... In this paper,we explore the use of iterative curvelet thresholding for seismic random noise attenuation.A new method for combining the curvelet transform with iterative thresholding to suppress random noise is demonstrated and the issue is described as a linear inverse optimal problem using the L1 norm.Random noise suppression in seismic data is transformed into an L1 norm optimization problem based on the curvelet sparsity transform. Compared to the conventional methods such as median filter algorithm,FX deconvolution, and wavelet thresholding,the results of synthetic and field data processing show that the iterative curvelet thresholding proposed in this paper can sufficiently improve signal to noise radio(SNR) and give higher signal fidelity at the same time.Furthermore,to make better use of the curvelet transform such as multiple scales and multiple directions,we control the curvelet direction of the result after iterative curvelet thresholding to further improve the SNR. 展开更多
关键词 curvelet transform iterative thresholding random noise attenuation
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Seismic dip estimation based on the twodimensional Hilbert transform and its application in random noise attenuation 被引量:7
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作者 刘财 陈常乐 +3 位作者 王典 刘洋 王世煜 张亮 《Applied Geophysics》 SCIE CSCD 2015年第1期55-63,121,共10页
In seismic data processing, random noise seriously affects the seismic data quality and subsequently the interpretation. This study aims to increase the signal-to-noise ratio by suppressing random noise and improve th... In seismic data processing, random noise seriously affects the seismic data quality and subsequently the interpretation. This study aims to increase the signal-to-noise ratio by suppressing random noise and improve the accuracy of seismic data interpretation without losing useful information. Hence, we propose a structure-oriented polynomial fitting filter. At the core of structure-oriented filtering is the characterization of the structural trend and the realization of nonstationary filtering. First, we analyze the relation of the frequency response between two-dimensional(2D) derivatives and the 2D Hilbert transform. Then, we derive the noniterative seismic local dip operator using the 2D Hilbert transform to obtain the structural trend. Second, we select polynomial fitting as the nonstationary filtering method and expand the application range of the nonstationary polynomial fitting. Finally, we apply variableamplitude polynomial fitting along the direction of the dip to improve the adaptive structureoriented filtering. Model and field seismic data show that the proposed method suppresses the seismic noise while protecting structural information. 展开更多
关键词 Two-dimensional Hilbert transform random noise attenuation structure protection nonstationary polynomial fitting local seismic d
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