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Liquefaction susceptibility and deformation characteristics of saturated coral sandy soils subjected to cyclic loadings-a critical review 被引量:1
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作者 Chen Guoxing Qin You +3 位作者 Ma Weijia Liang Ke Wu Qi C.Hsein Juang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期261-296,共36页
Coral sandy soils widely exist in coral island reefs and seashores in tropical and subtropical regions.Due to the unique marine depositional environment of coral sandy soils,the engineering characteristics and respons... Coral sandy soils widely exist in coral island reefs and seashores in tropical and subtropical regions.Due to the unique marine depositional environment of coral sandy soils,the engineering characteristics and responses of these soils subjected to monotonic and cyclic loadings have been a subject of intense interest among the geotechnical and earthquake engineering communities.This paper critically reviews the progress of experimental investigations on the undrained behavior of coral sandy soils under monotonic and cyclic loadings over the last three decades.The focus of coverage includes the contractive-dilative behavior,the pattern of excess pore-water pressure(EPWP)generation and the liquefaction mechanism and liquefaction resistance,the small-strain shear modulus and strain-dependent shear modulus and damping,the cyclic softening feature,and the anisotropic characteristics of undrained responses of saturated coral sandy soils.In particular,the advances made in the past decades are reviewed from the following aspects:(1)the characterization of factors that impact the mechanism and patterns of EPWP build-up;(2)the identification of liquefaction triggering in terms of the apparent viscosity and the average flow coefficient;(3)the establishment of the invariable form of strain-based,stress-based,or energy-based EPWP ratio formulas and the unique relationship between the new proxy of liquefaction resistance and the number of cycles required to reach liquefaction;(4)the establishment of the invariable form of the predictive formulas of small strain modulus and strain-dependent shear modulus;and(5)the investigation on the effects of stress-induced anisotropy on liquefaction susceptibility and dynamic deformation characteristics.Insights gained through the critical review of these advances in the past decades offer a perspective for future research to further resolve the fundamental issues concerning the liquefaction mechanism and responses of coral sandy sites subjected to cyclic loadings associated with seismic events in marine environments. 展开更多
关键词 liquefaction susceptibility dynamic deformation characteristics coral sandy soil cyclic loading review and prospect
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Volumetric lattice Boltzmann method for pore-scale mass diffusionadvection process in geopolymer porous structures
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作者 Xiaoyu Zhang Zirui Mao +6 位作者 Floyd W.Hilty Yulan Li Agnes Grandjean Robert Montgomery Hans-Conrad zur Loye Huidan Yu Shenyang Hu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2126-2136,共11页
Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste streams.To improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advecti... Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste streams.To improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advection process within porous structures is essential for material design.In this study,we present advancements in the volumetric lattice Boltzmann method(VLBM)for modeling and simulating pore-scale diffusion-advection of radioactive isotopes within geopolymer porous structures.These structures are created using the phase field method(PFM)to precisely control pore architectures.In our VLBM approach,we introduce a concentration field of an isotope seamlessly coupled with the velocity field and solve it by the time evolution of its particle population function.To address the computational intensity inherent in the coupled lattice Boltzmann equations for velocity and concentration fields,we implement graphics processing unit(GPU)parallelization.Validation of the developed model involves examining the flow and diffusion fields in porous structures.Remarkably,good agreement is observed for both the velocity field from VLBM and multiphysics object-oriented simulation environment(MOOSE),and the concentration field from VLBM and the finite difference method(FDM).Furthermore,we investigate the effects of background flow,species diffusivity,and porosity on the diffusion-advection behavior by varying the background flow velocity,diffusion coefficient,and pore volume fraction,respectively.Notably,all three parameters exert an influence on the diffusion-advection process.Increased background flow and diffusivity markedly accelerate the process due to increased advection intensity and enhanced diffusion capability,respectively.Conversely,increasing the porosity has a less significant effect,causing a slight slowdown of the diffusion-advection process due to the expanded pore volume.This comprehensive parametric study provides valuable insights into the kinetics of isotope uptake in porous structures,facilitating the development of porous materials for nuclear waste treatment applications. 展开更多
关键词 Volumetric lattice Boltzmann method(VLBM) Phase field method(PFM) Pore-scale diffusion-advection Nuclear waste treatment Porous media flow Graphics processing unit(GPU) PARALLELIZATION
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Engineering Nano/Microscale Chiral Self‑Assembly in 3D Printed Constructs
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作者 Mohsen Esmaeili Ehsan Akbari +3 位作者 Kyle George Gelareh Rezvan Nader Taheri‑Qazvini Monirosadat Sadati 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期313-332,共20页
Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living organisms.This study advances the integration of helical/ch... Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living organisms.This study advances the integration of helical/chiral assembly and 3D printing technology,providing precise spatial control over chiral nano/microstructures of rod-shaped colloidal nanoparticles in intricate geometries.We designed reactive chiral inks based on cellulose nanocrystal(CNC)suspensions and acrylamide monomers,enabling the chiral assembly at nano/microscale,beyond the resolution seen in printed materials.We employed a range of complementary techniques including Orthogonal Superposition rheometry and in situ rheo-optic measurements under steady shear rate conditions.These techniques help us to understand the nature of the nonlinear flow behavior of the chiral inks,and directly probe the flow-induced microstructural dynamics and phase transitions at constant shear rates,as well as their post-flow relaxation.Furthermore,we analyzed the photo-curing process to identify key parameters affecting gelation kinetics and structural integrity of the printed object within the supporting bath.These insights into the interplay between the chiral inks self-assembly dynamics,3D printing flow kinematics and photopolymerization kinetics provide a roadmap to direct the out-of-equilibrium arrangement of CNC particles in the 3D printed filaments,ranging from uniform nematic to 3D concentric chiral structures with controlled pitch length,as well as random orientation of chiral domains.Our biomimetic approach can pave the way for the creation of materials with superior mechanical properties or programable photonic responses that arise from 3D nano/microstructure and can be translated into larger scale 3D printed designs. 展开更多
关键词 Directed chiral self-assembly Cellulose nanocrystals Bioinspired nanocomposite 3D printing RHEOLOGY
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Clemastine in remyelination and protection of neurons and skeletal muscle after spinal cord injury 被引量:3
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作者 Ali Myatich Azizul Haque +1 位作者 Christopher Sole Naren L.Banik 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第5期940-946,共7页
Spinal cord injuries affect nearly five to ten individuals per million every year. Spinal cord injury causes damage to the nerves, muscles, and the tissue surrounding the spinal cord. Depending on the severity, spinal... Spinal cord injuries affect nearly five to ten individuals per million every year. Spinal cord injury causes damage to the nerves, muscles, and the tissue surrounding the spinal cord. Depending on the severity, spinal injuries are linked to degeneration of axons and myelin, resulting in neuronal impairment and skeletal muscle weakness and atrophy. The protection of neurons and promotion of myelin regeneration during spinal cord injury is important for recovery of function following spinal cord injury. Current treatments have little to no effect on spinal cord injury and neurogenic muscle loss. Clemastine, an Food and Drug Administration-approved antihistamine drug, reduces inflammation, protects cells, promotes remyelination, and preserves myelin integrity. Recent clinical evidence suggests that clemastine can decrease the loss of axons after spinal cord injury, stimulating the differentiation of oligodendrocyte progenitor cells into mature oligodendrocytes that are capable of myelination. While clemastine can aid not only in the remyelination and preservation of myelin sheath integrity, it also protects neurons. However, its role in neurogenic muscle loss remains unclear. This review discusses the pathophysiology of spinal cord injury, and the role of clemastine in the protection of neurons, myelin, and axons as well as attenuation of skeletal muscle loss following spinal cord injury. 展开更多
关键词 axonal damage CLEMASTINE MYELINATION neuronal death OLIGODENDROCYTES skeletal muscle spinal cord injury
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Comparison of point detection and area detection for point-scanning structured illumination microscopy
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作者 Wenshuai Wu Jiajie Chen +6 位作者 Meiting Wang Lei Wang Xiaomin Zheng Jia Li Junle Qu Bruce Zhi Gao Yonghong Shao 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2023年第4期134-149,共16页
Structured illumination microscopy(SIM)is suitable for biological samples because of its relatively low-peak illumination intensity requirement and high imaging speed.The system resolution is affected by two typical d... Structured illumination microscopy(SIM)is suitable for biological samples because of its relatively low-peak illumination intensity requirement and high imaging speed.The system resolution is affected by two typical detection modes:Point detection and area detection.However,a systematic analysis of the imaging performance of the different detection modes of the system has rarely been conducted.In this study,we compared laser point scanning point detection(PS-PD)and point scanning area detection(PS-AD)imaging in nonconfocal microscopy through theoretical analysis and simulated imaging.The results revealed that the imaging resolutions of PSPD and PS-AD depend on excitation and emission point spread functions(PSFs),respectively.Especially,we combined the second harmonic generation(SHG)of point detection(P-SHG)and area detection(A-SHG)with SIM to realize a nonlinear SIM-imaging technique that improves the imaging resolution.Moreover,we analytically and experimentally compared the nonlinear SIM performance of P-SHG with that of A-SHG. 展开更多
关键词 SUPER-RESOLUTION structured illumination microscopy second harmonic generation
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Whole‑genome transcriptome and DNA methylation dynamics of pre‑implantation embryos reveal progression of embryonic genome activation in buffaloes
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作者 Penghui Fu Du Zhang +8 位作者 Chunyan Yang Xiang Yuan Xier Luo Haiying Zheng Yanfei Deng Qingyou Liu Kuiqing Cui Fei Gao Deshun Shi 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2411-2427,共17页
Background During mammalian pre-implantation embryonic development(PED),the process of maternal-to-zygote transition(MZT)is well orchestrated by epigenetic modification and gene sequential expression,and it is related... Background During mammalian pre-implantation embryonic development(PED),the process of maternal-to-zygote transition(MZT)is well orchestrated by epigenetic modification and gene sequential expression,and it is related to the embryonic genome activation(EGA).During MZT,the embryos are sensitive to the environment and easy to arrest at this stage in vitro.However,the timing and regulation mechanism of EGA in buffaloes remain obscure.Results Buffalo pre-implantation embryos were subjected to trace cell based RNA-seq and whole-genome bisulfite sequencing(WGBS)to draw landscapes of transcription and DNA-methylation.Four typical developmental steps were classified during buffalo PED.Buffalo major EGA was identified at the 16-cell stage by the comprehensive analy-sis of gene expression and DNA methylation dynamics.By weighted gene co-expression network analysis,stage-spe-cific modules were identified during buffalo maternal-to-zygotic transition,and key signaling pathways and biological process events were further revealed.Programmed and continuous activation of these pathways was necessary for success of buffalo EGA.In addition,the hub gene,CDK1,was identified to play a critical role in buffalo EGA.Conclusions Our study provides a landscape of transcription and DNA methylation in buffalo PED and reveals deeply the molecular mechanism of the buffalo EGA and genetic programming during buffalo MZT.It will lay a foundation for improving the in vitro development of buffalo embryos. 展开更多
关键词 BUFFALO DNA methylome Embryonic genome activation Maternal-to-zygote transition TRANSCRIPTOME
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Celiac disease screening in patients with cryptogenic cirrhosis 被引量:1
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作者 Janaina Luz Narciso-Schiavon Leonardo Lucca Schiavon 《World Journal of Gastroenterology》 SCIE CAS 2023年第2期410-412,共3页
We write a letter to the editor commenting the article“Who to screen and how to screen for celiac disease”.We discuss the present literature on cirrhosis and celiac disease(CD)and recommend screening and treating CD... We write a letter to the editor commenting the article“Who to screen and how to screen for celiac disease”.We discuss the present literature on cirrhosis and celiac disease(CD)and recommend screening and treating CD in individuals with cryptogenic cirrhosis. 展开更多
关键词 Celiac disease Liver cirrhosis Liver failure Aspartate aminotransferase Alanine aminotransferase
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Improvement in Resolution of Multiphoton Scanning Structured Illumination Microscopy via Harmonics 被引量:1
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作者 Lei Wang Xiaomin Zheng +10 位作者 Jie Zhou Meiting Wang Jiajie Chen Youjun Zeng Gaixia Xu Ying Wang Haixia Qiu Yonghong Shao Junle Qu Bruce Zhi Gao Ying Gu 《Engineering》 SCIE EI CAS 2022年第9期65-72,共8页
We describe a multiphoton(mP)-structured illumination microscopy(SIM)technique,which demonstrates substantial improvement in image resolution compared with linear SIM due to the nonlinear response of fluorescence.This... We describe a multiphoton(mP)-structured illumination microscopy(SIM)technique,which demonstrates substantial improvement in image resolution compared with linear SIM due to the nonlinear response of fluorescence.This nonlinear response is caused by the effect of nonsinusoidal structured illumination created by scanning a sinusoidally modulated illumination to excite an mP fluorescence signal.The harmonics of the structured fluorescence illumination are utilised to improve resolution.We present an mP-SIM theory for reconstructing the super-resolution image of the system.Theoretically,the resolution of our m P-SIM is unlimited if all the high-order harmonics of the nonlinear response of fluorescence are considered.Experimentally,we demonstrate an 86 nm lateral resolution for two-photon(2P)-SIM and a 72 nm lateral resolution for second-harmonic-generation(SHG)-SIM.We further demonstrate their application by imaging cells stained with F-actin and collagen fibres in mouse-tail tendon.Our method can be directly used in commercial mP microscopes and requires no specific fluorophores or high-intensity laser. 展开更多
关键词 Super-resolution microscopy Structured illumination microscopy Multiphoton-structured illumination microscopy(SIM) SIM Second-harmonic-generation(SHG)-SIM
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Prevention of macrovascular complications in patients with type 2 diabetes mellitus: Review of cardiovascular safety and efficacy of newer diabetes medications 被引量:5
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作者 Ravi Kant Kashif M Munir +1 位作者 Arshpreet Kaur Vipin Verma 《World Journal of Diabetes》 SCIE CAS 2019年第6期324-332,共9页
Lack of conclusive beneficial effects of strict glycemic control on macrovascular complications has been very frustrating for clinicians involved in care of patients with diabetes mellitus (DM). Highly publicized cont... Lack of conclusive beneficial effects of strict glycemic control on macrovascular complications has been very frustrating for clinicians involved in care of patients with diabetes mellitus (DM). Highly publicized controversy surrounding cardiovascular (CV) safety of rosiglitazone resulted in major changes in United States Food and Drug Administration policy in 2008 regarding approval process of new antidiabetic medications, which has resulted in revolutionary data from several large CV outcome trials over the last few years. All drugs in glucagon-like peptide-1 receptor agonist (GLP-1 RA) and sodium-glucose cotransporter-2 (SGLT-2) inhibitor classes have shown to be CV safe with heterogeneous results on CV efficacy. Given twofold higher CV disease mortality in patients with DM than without DM, GLP-1 RAs and SGLT-2-inhibitors are important additions to clinician’s armamentarium and should be second line-therapy particularly in patients with T2DM and established atherosclerotic CV disease or high risks for CV disease. Abundance of data and heterogeneity in CV outcome trials results can make it difficult for clinicians, particularly primary care physicians, to stay updated with all the recent evidence. The scope of this comprehensive review will focus on all major CV outcome studies evaluating CV safety and efficacy of GLP-1 RAs and SGLT-2 inhibitors. 展开更多
关键词 Newer antidiabetic MEDICATIONS Glucagon-like peptide-1 receptor agonist Sodium-glucose cotransporter-2 inhibitors Type 2 DIABETES MELLITUS Macrovascular complications CARDIOVASCULAR outcome trials Major CARDIOVASCULAR events HEART failure PREVENTION of HEART disease
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Endoscopic balloon dilation for management of stricturing Crohn’s disease in children 被引量:1
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作者 Brianna McSorley Robert A Cina +2 位作者 Candi Jump Johanna Palmadottir J Antonio Quiros 《World Journal of Gastrointestinal Endoscopy》 2021年第9期382-390,共9页
BACKGROUND Crohn’s disease(CD)has a multitude of complications including intestinal strictures from fibrostenotic disease.Fibrostenotic disease has been reported in 10%-17%of children at presentation and leads to sur... BACKGROUND Crohn’s disease(CD)has a multitude of complications including intestinal strictures from fibrostenotic disease.Fibrostenotic disease has been reported in 10%-17%of children at presentation and leads to surgery in 20%-50%of cases within ten years of diagnosis.When symptoms develop from these strictures,the treatment in children has primarily been surgical resection.Endoscopic balloon dilation(EBD)has been shown to be a safe and efficacious alternative to surgery in adults,but evidence is poor in the literature regarding its safety and efficacy in children.AIM To evaluate the outcomes of children with fibrostenosing CD who underwent EBD vs surgery as a treatment.METHODS In a single-center retrospective study,we looked at pediatric patients(ages 0-18)who carry the diagnosis of CD,who were diagnosed after opening a dedicated Inflammatory Bowel Disease clinic on July 1,2012 through May 1,2019.We used diagnostic codes through our electronic medical record to identify patients with CD with a stricturing phenotype.The type of intervention for patients’strictures was then identified through procedural and surgical billing codes.We evaluated their demographics,clinical variables,whether they underwent EBD vs surgery or both,and their clinical outcomes.RESULTS Of the 139 patients with CD,25(18%)developed strictures.The initial intervention for a stricture was surgical resection in 12 patients(48%)and EBD in 13 patients(52%).However,4(33%)patients whom initially had surgical resection required follow up EBD,and thus 17 total patients(68%)underwent EBD at some point in their treatment process.For those 8 patients who underwent successful surgical resection alone,4 of these patients(50%)had a fistula present near the stricture site and 4(50%)had strictures greater than 5 cm in length.All patients who underwent EBD had no procedural complications,such as a perforation.Twenty-two(88%)of the treated strictures were successfully managed by EBD and did not require any further surgical intervention during our follow up period.CONCLUSION EBD is safe and efficacious as an alternative to surgery for palliative management of strictures in selected pediatric patients with CD. 展开更多
关键词 Crohn’s disease Intestinal strictures Endoscopic dilation PEDIATRICS Endoscopic balloon dilation
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Influences of the NAO on the North Atlantic CO2 Fluxes in Winter and Summer on the Interannual Scale
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作者 Yujie JING Yangchun LI +1 位作者 Yongfu XU Guangzhou FAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第11期1288-1298,共11页
The differences in the influences of the North Atlantic Oscillation (NAO) on the air–sea CO2 fluxes (fCO2) in the North Atlantic (NA) between different seasons and between different regions are rarely fully investiga... The differences in the influences of the North Atlantic Oscillation (NAO) on the air–sea CO2 fluxes (fCO2) in the North Atlantic (NA) between different seasons and between different regions are rarely fully investigated. We used observation-based data of fCO2, surface-ocean CO2 partial pressure (pCO2sea), wind speed and sea surface temperature (SST) to analyze the relationship between the NAO and fCO2 of the subtropical and subpolar NA in winter and summer on the interannual time scale. Based on power spectrum estimation, there are significant interannual signs with a 2–6 year cycle in the NAO indexes and area-averaged fCO2 anomalies in winter and summer from 1980 to 2015. Regression analysis with the 2–6 year filtered data shows that on the interannual scale the response of the fCO2 anomalies to the NAO has an obvious meridional wave-train-like pattern in winter, but a zonal distribution in summer. This seasonal difference is because in winter the fCO2 anomalies are mainly controlled by the NAO-driven wind speed anomalies, which have a meridional distribution pattern, while in summer they are dominated by the NAO-driven SST anomalies, which show distinct zonal difference in the subtropical NA. In addition, in the same season, there are different factors controlling the variation of pCO2sea in different regions. In summer, SST is important to the interannual variation of pCO2sea in the subtropical NA, while some biogeochemical variables probably control the pCO2sea variation in the subpolar NA. 展开更多
关键词 AIR-SEA CO2 flux North ATLANTIC Oscillation INTERANNUAL time SCALE wind speed surface-ocean CO2 partial pressure
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Sphingosine-1-phosphate signaling in vasculogenesis and angiogenesis 被引量:6
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作者 Kelley M Argraves Brent A Wilkerson W Scott Argraves 《World Journal of Biological Chemistry》 CAS 2010年第10期291-297,共7页
Blood vessels either form de novo through the process of vasculogenesis or through angiogenesis that involves the sprouting and proliferation of endothelial cells in pre-existing blood vessels. A complex interactive n... Blood vessels either form de novo through the process of vasculogenesis or through angiogenesis that involves the sprouting and proliferation of endothelial cells in pre-existing blood vessels. A complex interactive network of signaling cascades downstream from at least three of the nine known G-protein-coupled sphingosine-1-phosphate (S1P) receptors act as a prime effector of neovascularization that occurs in embryonic development and in association with various pathologies. This review focuses on the current knowledge of the roles of S1P signaling in vasculogenesis and angiogenesis, with particular emphasis on vascular cell adhesion and motility responses. 展开更多
关键词 Sphingosine-1-phosphate VASCULOGENESIS ANGIOGENESIS G-protein-coupled receptors ENDOTHELIUM
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Role of gut microbiota in cardiovascular diseases 被引量:7
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作者 Marko Novakovic Amit Rout +5 位作者 Thomas Kingsley Robert Kirchoff Amteshwar Singh Vipin Verma Ravi Kant Rahul Chaudhary 《World Journal of Cardiology》 CAS 2020年第4期110-122,共13页
The human gut is colonized by a community of microbiota,primarily bacteria,that exist in a symbiotic relationship with the host.Intestinal microbiota-host interactions play a critical role in the regulation of human p... The human gut is colonized by a community of microbiota,primarily bacteria,that exist in a symbiotic relationship with the host.Intestinal microbiota-host interactions play a critical role in the regulation of human physiology.Deleterious changes to the composition of gut microbiota,referred to as gut dysbiosis,has been linked to the development and progression of numerous diseases,including cardiovascular disease(CVD).Imbalances in host-microbial interaction impair homeostatic mechanisms that regulate health and can activate multiple pathways leading to CVD risk factor progression.Most CVD risk factors,including aging,obesity,dietary patterns,and a sedentary lifestyle,have been shown to induce gut dysbiosis.Dysbiosis is associated with intestinal inflammation and reduced integrity of the gut barrier,which in turn increases circulating levels of bacterial structural components and microbial metabolites,including trimethylamine-N-oxide and short-chain fatty acids,that may facilitate the development of CVD.This article reviews the normal function and composition of the gut microbiome,mechanisms leading to the leaky gut syndrome,its mechanistic link to CVD and potential novel therapeutic approaches aimed towards restoring gut microbiome and CVD prevention.As CVD is the leading cause of deaths globally,investigating the gut microbiota as a locus of intervention presents a novel and clinically relevant avenue for future research. 展开更多
关键词 CARDIOVASCULAR DISEASE Coronary artery DISEASE GUT MICROBIOTA DYSBIOSIS THROMBOSIS
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LITTLEWOOD-PALEY THEOREM FOR SCHR DINGER OPERATORS 被引量:2
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作者 Shijun Zheng 《Analysis in Theory and Applications》 2006年第4期353-361,共9页
Let H be a Schroedinger operator on R^n. Under a polynomial decay condition for the kernel of its spectral operator, we show that the Besov spaces and Triebel-Lizorkin spaces associated with H are well defined. We fur... Let H be a Schroedinger operator on R^n. Under a polynomial decay condition for the kernel of its spectral operator, we show that the Besov spaces and Triebel-Lizorkin spaces associated with H are well defined. We further give a Littlewood-Paley characterization of Lp spaces in terms of dyadic functions of H. This generalizes and strengthens the previous result when the heat kernel of H satisfies certain upper Gaussian bound. 展开更多
关键词 functional calculus SchrSdinger operator Littlewood-Paley theory
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Nonlinear control techniques for an atomic force microscope system 被引量:2
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作者 YongchunFANG MatthewFEEMSTER +1 位作者 DarrenDAWSON NaderM.JALILI 《控制理论与应用(英文版)》 EI 2005年第1期85-92,共8页
Two nonlinear control techniques are proposed for an atomic force microscopesystem. Initially, a learning-based control algorithm is developed for the microcantilever-samplesystem that achieves asymptotic cantilever t... Two nonlinear control techniques are proposed for an atomic force microscopesystem. Initially, a learning-based control algorithm is developed for the microcantilever-samplesystem that achieves asymptotic cantilever tip tracking for periodic trajectories. Specifically, thecontrol approach utilizes a learning-based feedforward term to compensate for periodic dynamics andhigh-gain terms to account for non-periodic dynamics. An adaptive control algorithm is thendeveloped to achieve asymptotic cantilever tip tracking for bounded tip trajectories despiteuncertainty throughout the system parameters. Simulation results are provided to illustrate theefficacy and performance of the control strategies. 展开更多
关键词 atomic force microscope adaptive control learning control lyapunov-basedstability analysis
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An Integrated Genetic,Physical and Transcript Map of Homoeologous Chromosomes 12 and 26 in Upland Cotton(Gossypium hirsutum L.) 被引量:2
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作者 KOHEL Russell J CHO Jaemin TOMKINS Jeffrey YU John Z 《棉花学报》 CSCD 北大核心 2008年第S1期22-,共1页
While Upland cotton(Gossypium hirsutum L.) represents 95% of the world production,its genetic improvement is hindered by the shortage of effective genomic tools and resources.The
关键词 An Integrated Genetic Physical and Transcript Map of Homoeologous Chromosomes 12 and 26 in Upland Cotton Gossypium hirsutum L
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On an Application of the Improved Maximum Product Criterion to Inverse Acoustic Scattering in a Layered Medium 被引量:1
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作者 Fermin S. Viloche Bazán Juliano de Bem Francisco +2 位作者 Koung Hee Leem George Pelekanos Vassilios Sevroglou 《Journal of Applied Mathematics and Physics》 2021年第4期661-682,共22页
In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well kn... In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well known <em>factorization method</em>, in which a computationally effective numerical scheme for the reconstruction of the shape of the scatterer is presented. This is possible, due to a <em>mixed reciprocity principle</em>, which renders the computation of the Green function at the background medium unnecessary. Moreover, to further refine our inversion algorithm, an efficient Tikhonov parameter choice technique, called <em>Improved Maximum Product Criterion</em> (IMPC) is exploited. Our regularization parameter is computed via a fast iterative algorithm which requires no <em>a priori</em> knowledge of the noise level in the far-field data. Finally, the effectiveness of IMPC is illustrated with various numerical examples. 展开更多
关键词 Acoustic Scattering Layered Medium Mixed Reciprocity Relation Factorization Method Improved Maximum Product Criterion (IMPC)
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Treatment with Intensity-Modulated Radiation Therapy (IMRT) and Chemotherapy in Advanced Inoperable Non-Small Cell Lung Cancer (NSCLC): Toxicity, Survival and Patterns of Failure in Relation to Treatment with High and Low Radiation Dose 被引量:3
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作者 James K. Russo Daniel Grass +5 位作者 Kent E. Armeson John Stahl Tarek Dufan John Reynolds Aaron Luebke Anand K. Sharma 《Journal of Cancer Therapy》 2015年第11期943-953,共11页
Purpose: To investigate the toxicity, survival and patterns of failure in patients with advanced lung cancer treated with intensity modulated radiation therapy (IMRT) and chemotherapy. Methods and Materials: Retrospec... Purpose: To investigate the toxicity, survival and patterns of failure in patients with advanced lung cancer treated with intensity modulated radiation therapy (IMRT) and chemotherapy. Methods and Materials: Retrospective chart review of 68 total patients: 46 academic and 22 community center. Endpoints: Grade ≥ 3 pneumonitis, Grade ≥ 2 esophagitis, local, regional and distant failure, progression-free survival (PFS) and overall survival (OS). Results: For the academic center patients, median follow-up was 19.2 months. Esophagitis: 0% Grade 3, 35% Grade 2, no significant difference between dose bins: <70 Gy vs. 70 Gy, 25% vs. 45% (p = 0.22), <66 Gy vs. 66 - 70 Gy, 28% vs. 39% (p = 0.53). Lung dose metrics and PTV size were not associated with Grade ≥ 3 pneumonitis. Esophageal V35, V50, and mean dose but not PTV size was associated with Grade 2 esophagitis. 1 year local, regional and distant failure = 6.5%, 6.5%, and 30.4%. No endpoint differences were seen between dose bins, though patients with smaller PTVs treated with 70 Gy did demonstrate improved OS (ns) when compared to those treated with <70 Gy. Community Center: Median follow-up 6.2 months with 15% Grade 2 esophagitis, no Grade 3 esophagitis. Two patients (9%) experienced Grade ≥ 3 pneumonitis. Conclusions: IMRT chemoradiation was well tolerated in a population with advanced NSCLC both in the academic and community settings. Severe pneumonitis rates were low and comparable to other series using IMRT and chemotherapy. Esophagitis was mild and associated with V35, V50 and mean dose. No significant benefit was seen for higher doses regarding survival, local, regional or distant control despite that higher dose bins had smaller tumors. Though not statistically significant, we did find a trend toward worse OS for <70 Gy when the PTV was less than the median PTV. 展开更多
关键词 IMRT NSCLC TOXICITY SURVIVAL Patterns of Failure CHEMOTHERAPY
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Abnormal Local Activity and Functional Dysconnectivity in Patients with Schizophrenia Having Auditory Verbal Hallucinations 被引量:4
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作者 Cheng CHEN Gao-hua WANG +3 位作者 Shi-hao WU Ji-lin ZOU Yuan ZHOU Hui-ling WANG 《Current Medical Science》 SCIE CAS 2020年第5期979-984,共6页
Auditory verbal hallucination(AVH)is emphasized as a pathological hallmark of schizophrenia.Neuroimaging studies provide evidence linking AVH to overlapping functional abnormalities in distributed networks.However,no ... Auditory verbal hallucination(AVH)is emphasized as a pathological hallmark of schizophrenia.Neuroimaging studies provide evidence linking AVH to overlapping functional abnormalities in distributed networks.However,no clear conclusion has still been reached.This study aimed to further explore the brain activity of patients with schizophrenia having AVH from both local activity(LA)and functional connectivity(FC)insights,while excluding confounding factors from other positive symptoms.A total of 42 patients with AVH(AVH patients group,APG),26 without AVH(non-AVH patients group,NPG),and 82 normal controls(NC)underwent resting-state functional magnetic resonance imaging(fMRI).LA measures,including regional homogeneity(ReHo)and fractional amplitude of low-frequency fluctuations(fALFF),and FC measures were evaluated to understand the neuroimaging mechanism of AVH.APG showed increased ReHo and fALFF in the bilateral putamen(Put)compared with NPG and NC.FC analysis(using bilateral putamen as seeds)revealed that all patients showed abnormal FC of multiple resting state network regions,including the anterior and post cingulate cortex,middle frontal gyrus,inferior parietal gyrus,and left angular gyrus.Interestingly,APG showed significantly decreased FC of insula extending to the superior temporal gyrus and inferior frontal gyrus compared with NPG and NC.The present findings suggested a significant correlation of abnormal LA and dysfunctional putamen-auditory cortical connectivity with the neuropathological mechanism of AVH,providing evidence for the functional disconnection hypothesis of schizophrenia. 展开更多
关键词 auditory verbal hallucination functional connectivity local activity resting-state functional magnetic resonance imaging SCHIZOPHRENIA
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Nonlinear scanning structured illumination microscopy based on nonsinusoidal modulation 被引量:1
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作者 Meiting Wang Lei Wang +6 位作者 Xiaomin Zheng Jie Zhou Jiajie Chen Youjun Zeng Junle Qu Yonghong Shao Bruce Zhi Gao 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2021年第5期25-32,共8页
Structured illumination microscopy(SIM)is an essential super-resolution microscopy technique that enhances resolution.Several images are required to reconstruct a super-resolution image.However,linear SIM resolution e... Structured illumination microscopy(SIM)is an essential super-resolution microscopy technique that enhances resolution.Several images are required to reconstruct a super-resolution image.However,linear SIM resolution enhancement can only increase the spatial resolution of micros-copy by a factor of two at most because the frequency of the structured illumination pattern is limited by the cutoff frequency of the excitation point spread function.The frequency of the pattern generated by the nonlinear response in samples is not limited;therefore,nonlinear SIM(NL-SIM),in theory,has no inherent limit to the resolution.In the present study,we describe a two-photon nonlinear SIM(2P-SIM)technique using a multiple harmonics scanning pattern that employs a composite structured illumination pattern,which can produce a higher order harmonic pattern based on the fluorescence nonlinear response in a 2P process.The theoretical models of super-resolution imaging were established through our simulation,which describes the working mechanism of the multi-frequency structure of the nonsinusoidal function to improve the reso-lution.The simulation results predict that a 5-fold improvement in resolution in the 2P-SIM is possible. 展开更多
关键词 Super-resolution image structured illumination microscopy nonsinusoidal function
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