scholarly journals The Relationship of Intradialytic Hypotension and Acute Effects of Hemodialysis on Heart: A Three‐dimensional Speckle Tracking Echocardiographic Study

2021 ◽  
Author(s):  
Hakan Kosku ◽  
Cansin Tulunay Kaya ◽  
Hasan Selim Guler ◽  
Muge Akbulut ◽  
Merve Aktar ◽  
...  
Keyword(s):  
Speckle Tracking ◽  
Three Dimensional ◽  
Intradialytic Hypotension ◽  
Acute Effects ◽  
Echocardiographic Study ◽  
Relationship Of ◽  
The Relationship

A Research on the Morphology and Composition of Flocs (Part 1: Floc Breaage Disregarded)

2013 ◽  
Vol 726-731 ◽  
pp. 1566-1572 ◽  
Author(s):  
Shi Qiang Ding ◽  
Qing Na Li ◽  
Xin Rong Pang ◽  
Ji Run Xu
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
New Classification ◽  
Suspension Viscosity ◽  
Primary Particles ◽  
Long Time ◽  
Relationship Of ◽  
The Relationship ◽  
Three Dimensional Space ◽  
Floc Breakage

The characteristics of flocs aggregated in flocculation have been paid more and more attention for a long time. In this paper, a new classification and analyses method dealing with the flocs is developed. The flocs formed after flocculation is divided into four kinds, including the left primary particles, linear flocs with all component particles in a line, planar flocs with all component particles on a plane and volumetric flocs with all component particles in a three-dimensional space. By analyzing the formation approaches of different kind of flocs regardless of the floc breakage, the number of every kind of floc is analyzed to be related with the suspension concentration mathematically. After comparing the different items in the models describing the relationship of floc number and concentration, a series of simplified expressions are presented. Lastly, a mathematical equation relating the measurable suspension viscosity with the numbers of different flocs is obtained.

scholarly journals Heart Rate Dependency and Inter-Lead Variability of the T Peak – T End Intervals

2020 ◽  
Vol 11 ◽  
Author(s):  
Irena Andršová ◽  
Katerina Hnatkova ◽  
Martina Šišáková ◽  
Ondřej Toman ◽  
Peter Smetana ◽  
...  
Keyword(s):  
Heart Rate ◽  
Three Dimensional ◽  
Rate Dependency ◽  
Rate Dependent ◽  
Heart Rate Correction ◽  
Ecg Leads ◽  
Relationship Of ◽  
The Relationship ◽  
Vector Magnitude

The electrocardiographic (ECG) assessment of the T peak–T end (Tpe) intervals has been used in many clinical studies, but several related physiological aspects have not been reported. Specifically, the sources of the Tpe differences between different ECG leads have not been systematically researched, the relationship of Tpe duration to underlying heart rate has not been firmly established, and little is known about the mutual correspondence of Tpe intervals measured in different ECG leads. This study evaluated 796,620 10-s 12-lead ECGs obtained from long-term Holters recorded in 639 healthy subjects (311 female) aged 33.8 ± 9.4 years. For each ECG, transformation to orthogonal XYZ lead was used to measure Tpe in the orthogonal vector magnitude (used as a reference for lead-to-lead comparisons) and to construct a three-dimensional T wave loop. The loop roundness was expressed by a ratio between its circumference and length. These ratios were significantly related to the standard deviation of Tpe durations in different ECG leads. At the underlying heart rate of 60 beats per minute, Tpe intervals were shorter in female than in male individuals (82.5 ± 5.6 vs 90.0 ± 6.5 ms, p < 0.0001). When studying linear slopes between Tpe intervals measured in different leads and the underlying heart rate, we found only minimal heart rate dependency, which was not systematic across the ECG leads and/or across the population. For any ECG lead, positive Tpe/RR slope was found in some subjects (e.g., 79 and 25% of subjects for V2 and V4 measurements, respectively) and a negative Tpe/RR slope in other subjects (e.g., 40 and 65% for V6 and V5, respectively). The steepest positive and negative Tpe/RR slopes were found for measurements in lead V2 and V4, respectively. In all leads, the Tpe/RR slope values were close to zero, indicating, on average, Tpe changes well below 2 ms for RR interval changes of 100 ms. On average, longest Tpe intervals were measured in lead V2, the shortest in lead III. The study concludes that the Tpe intervals measured in different leads cannot be combined. Irrespective of the measured ECG lead, the Tpe interval is not systematically heart rate dependent, and no heart rate correction should be used in clinical Tpe investigations.

Aerodynamic Characteristics Analysis of High-Speed Train on Cutting under Crosswinds

2013 ◽  
Vol 300-301 ◽  
pp. 62-67
Author(s):  
Kun Ye ◽  
Ren Xian Li
Keyword(s):  
High Speed ◽  
Three Dimensional ◽  
Aerodynamic Characteristics ◽  
High Speed Train ◽  
Aerodynamic Forces ◽  
Cutting Depth ◽  
Cutting Slope ◽  
Characteristics Analysis ◽  
Relationship Of ◽  
The Relationship

Cutting is an effective device to reduce crosswind loads acting on trains. The cutting depth, width and gradient of slope are important factors for design and construction of cutting. Based on numerical analysis methods of three-dimensional viscous incompressible aerodynamics equations, aerodynamic side forces and yawing moments acting on the high-speed train, with different depths and widths of cutting，are calculated and analyzed under crosswinds，meanwhile the relationship of the gradient of cutting slope and transverse aerodynamic forces acting on trains are also studied. Simulation results show that aerodynamic side forces and yawing moments acting on the train（the first, middle and rear train）decrease with the increase of cutting depth. The relationship between transverse forces (moments) coefficients acting on the three sections and the cutting depth basically is the three cubed relation. The bigger is cutting width，the worse is running stability of train. The relationship between yawing moments coefficients acting each body of the train and the cutting width approximately is the three cubed relation. The transverse Aerodynamic forces decreased gradually with the increase of the gradient of cutting slope, the relationship between yawing moments coefficients acting each body of the train and the gradient of cutting slope basically is the four cubed relation.

scholarly journals The three-dimensional lattice as an architectural space

2018 ◽  
Vol 212 ◽  
pp. 04005
Author(s):  
Andrey Bolshakov
Keyword(s):  
Three Dimensional ◽  
Human Movement ◽  
Theoretical Understanding ◽  
Architectural Space ◽  
Spatial Lattice ◽  
Spatial Grids ◽  
Relationship Of ◽  
The Relationship ◽  
Main Material

Space is the main material with which the architect works. The space organized by the means of architecture is an art environment for the life of society. With many aspects of the organization of space, which are studied in the literature, the problem of their assembly and integration remains unsolved. The paper proposes a method of assembling spatial representations in architecture-the correlation of the spatial lattice and the factors of its form-formation, considered in the system, i.e. together. The approach is that in a broad overview of the world architecture, both in its theory and in practice, from historical to modern, examples of modification of spatial grids under the influence of one or a group of dominant factors are revealed. As a result, provisions on the relationship of the geometry of spatial grids with the following factors have been revealed: publicity and privacy; architectonics, the influence of the lattice on the differentiation of the streams of human movement; the architecture’s ability to carry a message; navigation properties, evaluation of connectivity and centrality of places in the spatial lattice; evaluation of the quality of the composition through the identification of ways of order and randomness in the elements of the spatial lattice. The results of the work can be used both for theoretical understanding of the architectural space in the study and design of architecture, and in architectural education.

Structure and function of voltage-dependent sodium channels: comparison of brain II and cardiac isoforms

1996 ◽  
Vol 76 (3) ◽  
pp. 887-926 ◽  
Author(s):  
H. A. Fozzard ◽  
D. A. Hanck
Keyword(s):  
Amino Acid ◽  
Three Dimensional ◽  
Point Mutations ◽  
Amino Acid Sequences ◽  
Na Channel ◽  
Na Channels ◽  
Voltage Dependent ◽  
And Function ◽  
Relationship Of ◽  
The Relationship

Cardiac and nerve Na channels have broadly similar functional properties and amino acid sequences, but they demonstrate specific differences in gating, permeation, ionic block, modulation, and pharmacology. Resolution of three-dimensional structures of Na channels is unlikely in the near future, but a number of amino acid sequences from a variety of species and isoforms are known so that channel differences can be exploited to gain insight into the relationship of structure to function. The combination of molecular biology to create chimeras and channels with point mutations and high-resolution electrophysiological techniques to study function encourage the idea that predictions of structure from function are possible. With the goal of understanding the special properties of the cardiac Na channel, this review examines the structural (sequence) similarities between the cardiac and nerve channels and considers what is known about the relationship of structure to function for voltage-dependent Na channels in general and for the cardiac Na channels in particular.

scholarly journals Investigation of the classification and properties of three-dimensional textile fabrics

2019 ◽  
Vol 14 ◽  
pp. 155892501988996
Author(s):  
Zhenyu Ma ◽  
Pingze Zhang ◽  
Jianxun Zhu
Keyword(s):  
Three Dimensional ◽  
Physical And Mechanical Properties ◽  
Structural Features ◽  
Textile Composites ◽  
Uniform Structure ◽  
Fiber Volume ◽  
Textile Fabrics ◽  
And Performance ◽  
Relationship Of ◽  
The Relationship

Three-dimensional textile fabrics are used as the reinforcing phase of the textile structural composites, and their geometry affect the physical and mechanical properties of composites. Based on the curvature and directions of the fiber tows in three-dimensional textile fabrics, four representative geometric units are proposed, namely, the orthogonal geometric unit, the curved geometric unit, the skew geometric unit, and the uniform distribution unit, respectively. Other units are the combinations or derivations of these representative geometric units. The relationship and performance characteristics of these representative geometric units are discussed in section “The relationship of RGUs.” The structural features of three-dimensional textile fabrics are illustrated on the mesoscopic scale, and the models are established to predict the geometric properties. The concepts of fabrics with stable structure, flexible structure, elastoplastic structure, and uniform structure are proposed. The fiber volume fractions and elastic characteristics of different structural fabrics are discussed. The classification of three-dimensional textile fabrics is conducive to investigate the relationship between geometry and property, forming a technical system and providing a theoretical basis for the selection of three-dimensional structural textile composites with different performance.

A three-dimensional gravity model of the southern contact of the Sebago pluton, Maine

1998 ◽  
Vol 35 (6) ◽  
pp. 649-656 ◽  
Author(s):  
Mark D Behn ◽  
J Dykstra Eusden, Jr. ◽  
John A Notte III
Keyword(s):  
Three Dimensional ◽  
Average Thickness ◽  
Uniform Thickness ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Metasedimentary Rocks ◽  
The North ◽  
Dimensional Gravity ◽  
Relationship Of ◽  
The Relationship

The Sebago pluton is a two-mica granite that intruded the metasedimentary rocks of the Central Maine Terrane around 292 Ma. In recent years, geologists have raised an increasing number of questions related to the overall thickness of the Sebago pluton and the position of its subsurface contact with the underlying metasedimentary rocks. Past studies have shown the Sebago pluton to be a thin, 1-2 km thick, subhorizontal sheet dipping 3° to the northeast. This study examines anomalies in the Earth's gravitational field related to the southern portion of the Sebago pluton, specifically to determine the thickness of the pluton and to locate the subsurface contact between the pluton and the underlying metasedimentary rocks. A three-dimensional model shows the thickest portions of the pluton (~1.8 km) to occur at the bottom of a bowl hape along the southwestern contact. Moreover, the model shows the pluton to thin toward the northern and eastern regions of the study area, where the average thickness is less than 0.5 km. The pluton appears to extend southward below the cover of the metasedimentary rocks along the southwestern contact. Thus, contrary to previous models, the Sebago pluton is not a northeasterly dipping sheet of uniform thickness, but rather an arched sheet with an irregular thickness extending beneath the metasedimentary rocks along both its northern and southern contacts. Based on this new geometry, either the relationship of the pluton to the surrounding metamorphic zones must be modified, or the possibility must be considered that the Sebago pluton is actually a composite batholith, composed of a younger (Permian) granite to the north and an older (Carboniferous) granite to the south.

Sign in / Sign up

Export Citation Format

Share Document