Left ventricle geometry, atrial strain, ventricle strain and hemodynamics across aortic valve before and after transcatheter aortic valve replacements

Background: Transcatheter Aortic Valve Replacements (TAVR) has become widespread throughout the world. To date there are no echocardiographic study of TAVR patients from Southeast Asia (SEA). We sought to evaluate 1) changes in echocardiographic and strain values pre and post TAVR 2) relationship between aortic stenosis (AS) severity and strain values, 3) left ventricle geometry in severe AS 4) relationship of flow rate to dimensionless index (DVI) and acceleration time (AT) and 5) effect of strains on outcome. Methods: Retrospective study of 112 TAVR patients in our center from 2009 to 2020. The echocardiographic and strain images pre (within 1 months), post (day after) and 6 months post TAVR were analyzed by expert echocardiographer. Results: The ejection fraction (EF) increased at 6 months (53.02 ± 12.12% to 56.35 ± 9.00%) (p=0.044). Interventricular septal thickness in diastole (IVSd) decreased (1.27 ± 0.21cm to 1.21 ± 0.23cm) (p=0.038) and left ventricle internal dimension in diastole (LVIDd) decreased from 4.77 ± 0.64cm to 4.49 ± 0.65cm (p = 0.001). No changes in stroke volume index (SVI pre vs 6 months p =0.187), but the flow rate increases (217.80 ± 57.61mls/s to 251.94 ± 69.59mls/s, p<0.001). Global Longitudinal Strain (GLS) improved from -11.44 ± 4.23% to -13.94 ± 3.72% (p <0.001), Left Atrial Reservoir strain (Lar-S) increased from 17.44 ± 9.16% to 19.60 ± 8.77% (p=0.033). 8 patients (7.5%) had IVSd < 1.0cm, and 4 patients (3.7%) had normal left ventricle (LV) geometry. There was linear relationship between IVSd and mean PG (r=0.208, p=0.031), between GLS to aortic valve area (AVA) and aortic valve area index (AVAi) (r = – 0.305, p=0.001 and r= – 0.316, p = 0.001). There was also relationship between AT (r=-0.20, p=0.04) and DVI (r=0.35, p< 0.001) with flow rate. Patients who died late (after 6 months) had lower GLS at 6 months. (Alive; -13.94 ± 3.72% vs Died; -12.43 ± 4.19%, p= 0.001) Conclusion: At 6 months TAVR cause reverse remodeling of the LV with reduction in IVSd, LVIDd and improvement in GLS and LAr-S. There is linear relationship between GLS and AVA and between IVSd and AVA.

A Flow Cytometry-Based Assay for the Measurement of Total Complement Activity in the Serum and Clinical Practice

Objective. To develop a novel sensitive and accurate assay suitable for high-volume testing of the total complement activity in the serum for clinical laboratories. Methods. The total complement activity (TCA) to be measured was quantified by detecting the number of fragments produced by erythrocyte lysis and the erythrocyte fragmentation index (EFI), indicating TCA. EFI = M × M 2 / M 1 + M 2 , where M is the number of erythrocyte fragments (removed from the background), M 1 is the number of unagglutinated red cells, M 2 is the number of agglutinated red cell groups, and M 2 / M 1 + M 2 is the agglutination coefficient indicating the degree of erythrocyte agglutination. Mild changes in hemolysin and erythrocyte concentrations were made to optimize the testing conditions. The same serum samples were tested for 10 consecutive days to determine the stability of the experimental results. Serum EFI was detected in both nephrotic syndrome patients and healthy subjects. Results. There was a linear relationship between hemolysin and erythrocyte agglutination ( r = 0.999 , P < 0.001 ). A good linear relationship existed between EFI and TCA ( r = 0.991 , P < 0.001 ). The results were not affected by slight fluctuations in the concentrations of hemolysin or erythrocytes. The interbatch CV = 8.6 % of the test results showed good stability. There was a significant difference in the EFI between nephrotic syndrome patients and healthy individuals, P < 0.001 , and EFI was reduced in nephrotic syndrome patients compared to healthy individuals. Conclusion. The flow cytometry-based assay for TCA was sensitive and accurate and had potential value for clinical application.

Deviation from the Residue-Based Linear Free Energy Relationship Reveals a Non-Native Structure in Protein Folding

Multiprobe measurements, such as NMR and hydrogen exchange study, can provide the equilibrium constant K and kinetic rate constant k of the structural changes of a polypeptide on a per-residue basis. We previously found a linear relationship between residue-specific log K values and residue-specific log k values for the two-state topological isomerization of a 27-residue peptide. To test the general applicability of the residue-based linear free energy relationship (rbLEFR), we performed a literature search to collect residue-specific equilibrium and kinetic constants in various exchange processes, including protein folding, coupled folding and binding of intrinsically disordered peptides, and structural fluctuations of folded proteins. The good linearity in a substantial number of log-log plots proved that the rbLFER holds for the structural changes in a wide variety of protein-related phenomena. Protein molecules quickly fold into their native structures and change their conformations smoothly. Theoretical studies and molecular simulations advocate that the physicochemical basis is the consistency principle and the minimal frustration principle: Non-native structures/interactions are absent or minimized along the folding pathway. The linearity of the residue-based free energy relationship demonstrates experimentally the absence of non-native structures in transition states. In this context, the hydrogen exchange study of apomyoglobin folding intermediates is particularly interesting. We found that the residues that deviated from the linear relationship corresponded to the non-native structure, which had been identified by other experiments. The rbLFER provides a unique and practical method to probe the dynamic aspects of the transition states of protein molecules.

Analysis of the Relationship between the Density and Lane-Changing Behavior of Circular Multilane Urban Expressway in Mixed Traffic

The behavior of changing lanes has a great impact on road traffic with heavy traffic. Traffic flow density is one of the important parameters that characterize the characteristics of traffic flow, and it will also be affected by the behavior of changing lanes, especially in the case of each lane. The penetration of autonomous vehicles can effectively reduce lane-changing behavior. Studying the relationship between traffic flow density and lane-changing behavior under different autonomous vehicle penetration rates is of great significance for describing the operation mechanism of mixed traffic flow and the control of mixed traffic. In this article, we use empirical, simulation, and data-driven methods to analyze the urban expressway of autonomous vehicles with penetration rates of 10%, 20%, 30%, 40%, 50%, 60%, 70%, and 80%, respectively. A simulation experiment was carried out on the road, and data related to density, the rate of changing into the lanes, and the rate of changing out lanes were collected. The analysis of the experimental results found the following: (1) The increase in penetration of autonomous vehicles leads to a certain degree of downward trend in density, the rate of changing into the lanes, and the rate of changing out lanes. (2) Different lanes have different effects on the penetration of autonomous vehicles. In a 4-lane road, the two lanes farther from the entrance and exit are closer in appearance, while the two lanes closer to the entrance and exit are similar. (3) The relationship between density and the rate of changing into the lanes and the rate of changing out lanes shows a linear relationship with the penetration of autonomous vehicles. Although the performance of each lane is slightly different, in general, it can be carried out by a multiple regression model. The given parameter value range is relatively close under different permeability. In summary, autonomous vehicles effectively reduce the traffic density and lane-changing behavior of each lane. There is a linear relationship between traffic flow density and lane-changing behavior with the penetration of autonomous vehicles. The density-lane-changing behavior model proposed in this paper can better describe the relationship between the density of the circular multilane urban expressway and the lane-changing behavior in the case of a large traffic flow in mixed traffic.

Daily rainfall persistence over Sri Lanka

The spatial distribution of daily rainfall persistence is examined adopting Besson's persistence coefficient and using daily rainfall data for 15 consecutive years (1971-1985). The daily rainfall persistence coefficients have been studied separately for all the twelve months individually and for the whole year. Where January and February indicate the lowest rainfall persistence coefficients the period from October to December indicates the highest coefficients over Sri Lanka. Besides the monsoonal atmospheric conditions, the topography has a strong influence on the rainfall persistence distribution over space and time. The daily rainfall persistence coefficients record higher values in the wet zone then in the dry zone of Sri Lanka. Regression analysis shows a better linear relationship between mean length of wet spell~ and the daily rainfall persistence coefficients and the resultant final equation is y.4' =0.1093+0.1600+X M having the correlation coefficient of 0.721 which is significant at the 0.01% level.

Effect of Pulsed Jet on Pore Pressure of Deep Formation Rock

Pulsed jet significantly affects the pore pressure of deep formation and then affects the mechanical ROP. In this paper, the effect of jet pulsation on deep pore pressure in the formation is studied by the finite element method. Under the pulsed jet, the maximum relative negative pressure is along the wellbore axis, and the farther it is to the borehole axis, the smaller the relative negative pressure is. With the increase of pulse frequency, the relative negative pressure increases and the maximum point of relative negative pressure moves upward. The optimum pulse frequency is from 50 Hz to 500 Hz. There is a linear relationship between pulse amplitude and relative negative pressure.

Effect of buyer dependency of subcontracting SMEs on R&D investment

PurposeThis study aims to focus on the subcontracting relationship between small and medium-sized enterprises (SMEs) and business group buyers and analyze the effect of the level of buyer dependency on R&D intensity. The primary prediction is that buyer dependency and R&D intensity have a non-linear relationship, showing an inverted U-shaped relationship. Furthermore, the moderating effect of founder CEOs and internationalization is explored.Design/methodology/approachA sample of 546 firm-level survey responses were collected from Korean subcontracting SMEs provided by the Ministry of SMEs and Startups and the Korea Venture Business Association.FindingsA lower level of dependency on business group buyers promotes R&D investment, while excessive dependence reduces R&D investment. Moreover, founder CEOs and internationalization decrease the effect of buyer dependency on R&D investment, implying that both firm characteristics are associated with a long-term focus and promote R&D investment.Research limitations/implicationsThis research contributes to the literature on the special form of the buyer–supplier relationship, that is, subcontracting. Subcontracting has a contradictory effect on R&D investment based on large group buyer dependency, and this relationship is moderated by the founder CEO and internationalization.Practical implicationsThis study provides insights to managers and practitioners governing SME subcontracting by showing that the level of buyer dependency is better managed in promoting innovation, and the long-term perspective allows SMEs to be less affected by buyer dependency.Originality/valueThis study extends the literature by focusing on the non-linear relationship between buyer dependency and R&D intensity of subcontracting SMEs. This approach addresses the contradicting results suggested by prior supply chain management literature and suggests that the level of buyer dependency should be considered when analyzing the subcontracting relationship.

How Does Misperception Affect Zero-Determinant Strategies In Iterated Prisoner’s Dilemma?

Zero-determinant (ZD) strategies have attracted wide attention in Iterated Prisoner’s Dilemma (IPD) games, since the player equipped with ZD strategies can unilaterally enforce the two players’ expected utilities subjected to a linear relation. On the other hand, uncertainties, which may be caused by misperception, occur in IPD inevitably in practical circumstances. To better understand the situation, we consider the influence of misperception on ZD strategies in IPD, where the two players, player X and player Y , have different cognitions, but player X detects the misperception and it is believed to make ZD strategies by player Y. We provide a necessary and sufficient condition for the ZD strategies in IPD with misperception, where there is also a linear relationship between players’ utilities in player X’s cognition. Then we explore bounds of players’ expected utility deviation from a linear relationship in player X’s cognition with also improving its own utility.

THE EFFECT OF THE WEYL FRACTIONAL INTEGRAL ON FUNCTIONS

This paper mainly discusses the influence of the Weyl fractional integrals on continuous functions and proves that the Weyl fractional integrals can retain good properties of many functions. For example, a bounded variation function is still a bounded variation function after the Weyl fractional integral. Continuous functions that satisfy the Holder condition after the Weyl fractional integral still satisfy the Holder condition, furthermore, there is a linear relationship between the order of the Holder conditions of the two functions. At the end of this paper, the classical Weierstrass function is used as an example to prove the above conclusion.