After the success of the Daya Bay experiment, the Jiangmen Underground Neutrino Observatory （JUNO） was launched to measure neutrino-mass hierarchy and oscillation parameters and to study other neutrino physics. Its ...After the success of the Daya Bay experiment, the Jiangmen Underground Neutrino Observatory （JUNO） was launched to measure neutrino-mass hierarchy and oscillation parameters and to study other neutrino physics. Its central detector is set for antineutrinos from reactors, the Earth, the atmosphere, and the Sun. The main requirements of the central detector are con- tainment of 20 kt of liquid scintillator, as the target mass, and 3% energy resolution. It is about a ball-shape detector of 38.5 m with -75% coverage of PMT on its inner surface. The design of such a huge detector is a big challenge because it must meet the requirements for several different types of physics measurement and possess the feasibility and reliability in its structure and engineering, all at reasonable time and cost. One option for the JUNO central detector is a hyper-scale acrylic ball sub- merged in the water to shield the background. This paper proposes a structural scheme for such an acrylic ball that is supported by a stainless-steel truss, inspired by point-supported glass-curtain walls in civil engineering. The preliminary design of the scheme is completed and verified by finite element （FE） method using ABAQUS. FE analysis shows that the scheme can con- trol the stress level of the acrylic ball within the limit of 5 to 10 MPa, in accordance with the demand of the design objective of the central detector. The scheme is of outstanding global stability and allows various chocces on local connections. We prove that the scheme is of good feasibility and should be a reasonable option for the central detector.展开更多
Based on multiple types of data, the topographical features of the Okinawa Trough(OT) have been characterized and a computation method has been proposed to determine the break point of continental shelf(BOS), foot poi...Based on multiple types of data, the topographical features of the Okinawa Trough(OT) have been characterized and a computation method has been proposed to determine the break point of continental shelf(BOS), foot point of the continental slope(FOS), the central axial point, and the maximum depth point. A total of 48 topographical profiles that crosscut the continental slope have been used to determine the trends of the BOS and FOS(the BOS and FOS lines) in the East China Sea(ECS). The trend of central axial points in the OT has been similarly determined by analyzing 39 topographical profiles across the axis of the trough. The BOS line forms the boundary between the continental shelf and slope. In the ECS, the BOS line roughly follows the 200 m isobath, continuously in the northern and middle parts of the OT, but jumping about somewhat in the south. The FOS line is the boundary between the continental slope and the bottom of the trough. The depth of the FOS increases gradually from north to south in the OT. Intense incisions by canyons into the slope in the southern part of the trough have led to the complex distribution of FOS. Topographical profiles crosscutting the northern, middle, and southern parts of the OT exhibit features that include: a single W-shape, a composite W-shape, and a U-shape, respectively, which suggests that in the middle and northern parts of the trough the central axial points are always located on seamount peaks or ridges associated with linear seamounts, whereas in the south they are found in the center of en echelon depressions. The line formed by the central axial points is the east-west dividing line of the OT, which indicates that the trough is a natural gap that prevents the extension of ECS continental shelf to the east. The distributions of the BOS and FOS lines are influenced by fluctuation of sea levels and submarine canyons, whereas the distribution of axis lines is controlled by tectonics and deposition.展开更多
In this paper, the dynamical properties of Smith type diffusion model with Dirichlet boundary conditions are studied. The properties of hyperbolic fixed points and non-hyperbolic fixed points of the model are analyzed...In this paper, the dynamical properties of Smith type diffusion model with Dirichlet boundary conditions are studied. The properties of hyperbolic fixed points and non-hyperbolic fixed points of the model are analyzed. By using the central manifold theorem, the bifurcation phenomenon of the model is studied. The results show that flip, transcritical, pitchfork and Fold-flip bifurcations exist at non-hyperbolic fixed points.展开更多
Central venous pressure(CVP)serves as a direct approximation of right atrial pressure and is influenced by factors like total blood volume,venous compliance,cardiac output,and orthostasis.Normal CVP falls within 8-12 ...Central venous pressure(CVP)serves as a direct approximation of right atrial pressure and is influenced by factors like total blood volume,venous compliance,cardiac output,and orthostasis.Normal CVP falls within 8-12 mmHg but varies with volume status and venous compliance.Monitoring and managing disturbances in CVP are vital in patients with circulatory shock or fluid disturbances.Elevated CVP can lead to fluid accumulation in the interstitial space,impairing venous return and reducing cardiac preload.While pulmonary artery catheterization and central venous catheter obtained measurements are considered to be more accurate,they carry risk of complications and their usage has not shown clinical improvement.Ultrasound-based assessment of the internal jugular vein(IJV)offers real-time,non-invasive measurement of static and dynamic parameters for estimating CVP.IJV parameters,including diameter and ratio,has demonstrated good correlation with CVP.Despite significant advancements in non-invasive CVP measurement,a reliable tool is yet to be found.Present methods can offer reasonable guidance in assessing CVP,provided their limitations are acknowledged.展开更多
In this editorial we comment on the article by Kuwahara et al,published in the recent issue of the World Journal of Cardiology.In this interesting paper,the authors showed a correlation between portal vein pulsatility...In this editorial we comment on the article by Kuwahara et al,published in the recent issue of the World Journal of Cardiology.In this interesting paper,the authors showed a correlation between portal vein pulsatility ratio,examined by bedside ultrasonography,and prognosis of hospitalized patients with acute heart failure.Systemic congestion is being notoriously underdetected in the acutely ill population with conventional methods like clinical examination,biomarkers,central venous pressure estimation and X-rays.However,congestion should be a key therapeutic target due to its deleterious effects to end organ function and subsequently patient prognosis.Doppler flow assessment of the abdominal veins is gaining popularity worldwide,as a valuable tool in estimating comprehensively congestion and giving a further insight into hemodynamics and patient management.展开更多
In today's healthcare,clinical laboratory medicine stands as a cornerstone of patient care,providing vital diagnostic insights that inform decisions in disease management.Yet,within this crucial field,a dichotomy ...In today's healthcare,clinical laboratory medicine stands as a cornerstone of patient care,providing vital diagnostic insights that inform decisions in disease management.Yet,within this crucial field,a dichotomy persists between two predominant models of laboratory testing to support clinical practice:point-of-care testing(PoCT)and central laboratory testing[1].This schism,while born of practical necessity and evolving technology,presents both opportunities and challenges that warrant closer examination.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA10010200)the Tsinghua University Initiative Scientific Research Program(Grant No.20131089288)
文摘After the success of the Daya Bay experiment, the Jiangmen Underground Neutrino Observatory （JUNO） was launched to measure neutrino-mass hierarchy and oscillation parameters and to study other neutrino physics. Its central detector is set for antineutrinos from reactors, the Earth, the atmosphere, and the Sun. The main requirements of the central detector are con- tainment of 20 kt of liquid scintillator, as the target mass, and 3% energy resolution. It is about a ball-shape detector of 38.5 m with -75% coverage of PMT on its inner surface. The design of such a huge detector is a big challenge because it must meet the requirements for several different types of physics measurement and possess the feasibility and reliability in its structure and engineering, all at reasonable time and cost. One option for the JUNO central detector is a hyper-scale acrylic ball sub- merged in the water to shield the background. This paper proposes a structural scheme for such an acrylic ball that is supported by a stainless-steel truss, inspired by point-supported glass-curtain walls in civil engineering. The preliminary design of the scheme is completed and verified by finite element （FE） method using ABAQUS. FE analysis shows that the scheme can con- trol the stress level of the acrylic ball within the limit of 5 to 10 MPa, in accordance with the demand of the design objective of the central detector. The scheme is of outstanding global stability and allows various chocces on local connections. We prove that the scheme is of good feasibility and should be a reasonable option for the central detector.
基金supported by Public Science and Technology Research Funds Project of Ocean(Grant No.201105001)Fundamental Project of Science and Technology(Grant No.2013FY112900)National Natural Science Foundation of China(Grant Nos.40506017,41206046)
文摘Based on multiple types of data, the topographical features of the Okinawa Trough(OT) have been characterized and a computation method has been proposed to determine the break point of continental shelf(BOS), foot point of the continental slope(FOS), the central axial point, and the maximum depth point. A total of 48 topographical profiles that crosscut the continental slope have been used to determine the trends of the BOS and FOS(the BOS and FOS lines) in the East China Sea(ECS). The trend of central axial points in the OT has been similarly determined by analyzing 39 topographical profiles across the axis of the trough. The BOS line forms the boundary between the continental shelf and slope. In the ECS, the BOS line roughly follows the 200 m isobath, continuously in the northern and middle parts of the OT, but jumping about somewhat in the south. The FOS line is the boundary between the continental slope and the bottom of the trough. The depth of the FOS increases gradually from north to south in the OT. Intense incisions by canyons into the slope in the southern part of the trough have led to the complex distribution of FOS. Topographical profiles crosscutting the northern, middle, and southern parts of the OT exhibit features that include: a single W-shape, a composite W-shape, and a U-shape, respectively, which suggests that in the middle and northern parts of the trough the central axial points are always located on seamount peaks or ridges associated with linear seamounts, whereas in the south they are found in the center of en echelon depressions. The line formed by the central axial points is the east-west dividing line of the OT, which indicates that the trough is a natural gap that prevents the extension of ECS continental shelf to the east. The distributions of the BOS and FOS lines are influenced by fluctuation of sea levels and submarine canyons, whereas the distribution of axis lines is controlled by tectonics and deposition.
文摘In this paper, the dynamical properties of Smith type diffusion model with Dirichlet boundary conditions are studied. The properties of hyperbolic fixed points and non-hyperbolic fixed points of the model are analyzed. By using the central manifold theorem, the bifurcation phenomenon of the model is studied. The results show that flip, transcritical, pitchfork and Fold-flip bifurcations exist at non-hyperbolic fixed points.
文摘Central venous pressure(CVP)serves as a direct approximation of right atrial pressure and is influenced by factors like total blood volume,venous compliance,cardiac output,and orthostasis.Normal CVP falls within 8-12 mmHg but varies with volume status and venous compliance.Monitoring and managing disturbances in CVP are vital in patients with circulatory shock or fluid disturbances.Elevated CVP can lead to fluid accumulation in the interstitial space,impairing venous return and reducing cardiac preload.While pulmonary artery catheterization and central venous catheter obtained measurements are considered to be more accurate,they carry risk of complications and their usage has not shown clinical improvement.Ultrasound-based assessment of the internal jugular vein(IJV)offers real-time,non-invasive measurement of static and dynamic parameters for estimating CVP.IJV parameters,including diameter and ratio,has demonstrated good correlation with CVP.Despite significant advancements in non-invasive CVP measurement,a reliable tool is yet to be found.Present methods can offer reasonable guidance in assessing CVP,provided their limitations are acknowledged.
文摘In this editorial we comment on the article by Kuwahara et al,published in the recent issue of the World Journal of Cardiology.In this interesting paper,the authors showed a correlation between portal vein pulsatility ratio,examined by bedside ultrasonography,and prognosis of hospitalized patients with acute heart failure.Systemic congestion is being notoriously underdetected in the acutely ill population with conventional methods like clinical examination,biomarkers,central venous pressure estimation and X-rays.However,congestion should be a key therapeutic target due to its deleterious effects to end organ function and subsequently patient prognosis.Doppler flow assessment of the abdominal veins is gaining popularity worldwide,as a valuable tool in estimating comprehensively congestion and giving a further insight into hemodynamics and patient management.
文摘In today's healthcare,clinical laboratory medicine stands as a cornerstone of patient care,providing vital diagnostic insights that inform decisions in disease management.Yet,within this crucial field,a dichotomy persists between two predominant models of laboratory testing to support clinical practice:point-of-care testing(PoCT)and central laboratory testing[1].This schism,while born of practical necessity and evolving technology,presents both opportunities and challenges that warrant closer examination.
