Role of Diffusion in the Kinetics of Reversible Enzyme-catalyzed Reactions

Szabo, Attila,Zhou, Huan-Xiang Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.3

The accurate expression for the steady-state velocity of an irreversible enzyme-catalyzed reaction obtained by Shin and co-workers (J. Chem. Phys. 2001, 115, 1455) is generalized to allow for the rebinding of the product. The amplitude of the power-law ($t^{-1/2}$) relaxation of the free- and bound-enzyme concentrations to steady-state values is expressed in terms of the steady-state velocity and the intrinsic (chemical) rate constants. This result is conjectured to be exact, even though our expression for the steady-state velocity in terms of microscopic parameters is only approximate.

Role of Diffusion in the Kinetics of Reversible Enzyme-catalyzed Reactions

Attila Szabo,Huan-Xiang Zhou 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.3

The accurate expression for the steady-state velocity of an irreversible enzyme-catalyzed reaction obtained by Shin and co-workers (J. Chem. Phys. 2001, 115, 1455) is generalized to allow for the rebinding of the product. The amplitude of the power-law (t–1/2) relaxation of the free- and bound-enzyme concentrations to steady-state values is expressed in terms of the steady-state velocity and the intrinsic (chemical) rate constants. This result is conjectured to be exact, even though our expression for the steady-state velocity in terms of microscopic parameters is only approximate.

Psychological Effects of Fast- and Slow-Tempo Music Played during Volleyball Training in a National League Team

( Attila Szabo ),( Lorna J. Hoban ) 한국스포츠정책과학원(구 한국스포츠개발원) 2004 International Journal of Applied Sports Sciences Vol.16 No.2

This study examined whether music could benefit the training experience in a British national league volleyball team. Nine female volleyball players were tested in two identical studies in three different training sessions: control (no music), slow-music, and fast-music. Players` affect and state anxiety were measured before and after each training session. Perceived effort was assessed at halftimes during training, whereas preference for the session was gauged after each session. Feelings of revitalisation and positive engagement have decreased significantly when slow music was played in the background. A similar trend in the control session was also evident. Perceived effort was lower in the fast-tempo music than control session, but it was the lowest during the slow-music training session. Players` preference for training in presence of slow music was significantly lower than their preference for training without any music or with fast music. It is concluded that slow, asynchronous, music impairs the quality of training, but fast-tempo arousing music may enhance the quality of training not necessarily by inducing major changes in affect but primarily by reducing the perception of effort in volleyball training. Therefore, fast music that is synchronised with the movement-rhythm could enhance the quality of training in female volleyball teams.

Relationship between Physical Exercise Workload, Information Processing Speed, and Affect

( Maria Rendi ),( Attila Szabo ),( Tamas Szabo ) 한국스포츠정책과학원(구 한국스포츠개발원) 2007 International Journal of Applied Sports Sciences Vol.19 No.1

Twenty healthy young women participated in thislaboratory research. They completed the Exercise Induced Inventory (EFI - Gauvin & Rejeski, 1993) before, immediately after, and 15-mins after a 20-minute progressive treadmill exercise during which they ran for 5-mins at 50%, 60%, 70% and 80% of their maximal heart rate reserve (MHRR). Before, during every stage of exercise, and twice after exercise, the participants were asked to continuously identify a letter in a specific position in unexpected words - presented in 8 second intervals over a period of three minutes - while their information processing speed (IPS) was gauged. Results showed that IPS was shortest when participants ran at 80% of MHRR, suggesting that quick mental choices are made easier under heightened levels of arousal. No changes in affect (transient mood states) from pre- to post-exercise were seen. These findings appear to support the circumplex model of affect claiming that affective valence is invariant (unchanged) when distracting mental tasks are undertaken during exercise.

Assessment of genetic diversity and phylogenetic relationship of Limousin herds in Hungary using microsatellite markers

Marton Szucs,Ferenc Szabo,Beata Ban,Csilla Jozsa,Laszlo Rozsa,Attila Zsolnai,Istvan Anton 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.2

Objective: This study was conducted to investigate basic information on genetic structure and characteristics of Limousin population in Hungary. Obtained results will be taken into consideration when adopting the new breeding strategy by the Association of Hungarian Limousin and Blonde d'Aquitaine Breeders (AHLBB). Methods: Genetic diversity and phylogenetic relationship of 3,443 Limousin cattle from 16 different herds were investigated by performing genotyping using 18 microsatellite markers. Amplified DNA was genotyped using an automated genetic analyzer. Results: Mean of effective alleles (ne) of the populations was 3.77. Population C had the lowest number of effective alleles (3.01) and the lowest inbreeding coefficient (FIS) value (–0.15). Principal component analysis of estimated genetic distance (FST) values (p<0.000) revealed two herds (C and E) distinct from the majority of other Limousin herds. The pairwise FST values of population C compared to the others (0.066 to 0.120) fell into the range of moderate genetic distance: 0.050 to 0.150, while population E displayed also moderate genetic distance (FST values in range 0.052 to 0.064) but only to six populations (G, H, J, L, N, and P). FST(C-E) was 0.148, all other pairs -excluding C and E herds- displayed low genetic distance (FST<0.049). Population D, F, I, J, K, L, N, O, and P carried private alleles, which alleles belonged to 1.1% of the individuals. Most probable number of clusters (K) were 2 and 7 determined by Structure and BAPS software. Conclusion: This study showed useful genetic diversity and phylogenetic relationship data that can be utilized for the development of a new breeding strategy by AHLBB. The results presented could also contribute to the proper selection of animals for further whole genome scan studies of Limousins.

Resilient Reduced-State Resource Reservation

Csaszar Andras,Takacs Attila,Szabo Robert,Henk Tamas The Korea Institute of Information and Commucation 2005 Journal of communications and networks Vol.7 No.4

Due to the strict requirements of emerging applications, per-flow admission control is gaining increasing importance. One way to implement per-flow admission control is using an on­path resource reservation protocol, where the admission decision is made hop-by-hop after a new flow request arrives at the network boundary. The next-steps in signaling (NSIS) working group of the Internet engineering task force (IETF) is standardising such an on-path signaling protocol. One of the reservation methods considered by NSIS is reduced-state mode, which, suiting the differentiated service (DiffServ) concept, only allows per-class states in interior nodes of a domain. Although there are clear benefits of not dealing with per-flow states in interior nodes-like scalability and low complexity-, without per-flow states the handling of re-routed flows, e.g., after a failure, is a demanding and highly non-trivial task. To be applied in carrier-grade networks, the protocol needs to be resilient in this situation. In this article, we will explain the consequences of a route failover to resource reservation protocols: Severe congestion and incorrect admission decisions due to outdated reservation states. We will set requirements that handling solutions need to fulfill, and we propose extensions to reduced-state protocols accordingly. We show with a set of simulated scenarios that with the given solutions reduced-state protocols can handle re-routed flows practically as fast and robust as stateful protocols.

Are frailty scales better than anesthesia or surgical scales to determine risk in cardiac surgery?

Judit Kovacs,Liviu Moraru,Krisztina Antal,Adrian Cioc,Septimiu Voidazan,Attila Szabo 대한마취통증의학회 2017 Korean Journal of Anesthesiology Vol.70 No.2

Background: In the last year there has been an increasing interest for using frailty scales for risk stratification of elderly patients undergoing major surgery. We planned to compare two frailty scales with risk scales already used in cardiac surgery, to study which of these scores have better prognostic value predicting postoperative outcome in open heart surgery. Methods: We conducted a prospective clinical trial, including 57 patients over 65 years. We calculated Cardiac Anesthesia Risk Evaluation score, EuroScore II, Clinical Frailty Scale, Edmonton Frail Scale for each patient and followed the postoperative complications, length of mechanical ventilation, length of stay in the intensive care unit and hospital, and in-hospital death related to these risk and frailty scores. Results: Postoperative complications occurred in 25 patients (43.9%), while four patients (7%) died with multiple organ failure. All scales had low predictability for postoperative complications, but for length of mechanical ventilation we obtained positive correlations with EuroScore II, Edmonton Frail Scale and Clinical Frailty Scale. EuroScore II can also predict the length of stay in the intensive care unit. For postoperative deaths, the highest sensitivity had EuroScore II, followed by Clinical Frailty Scale and Edmonton Frail Scale. Conclusions: EuroScore II and the frailty scales have an increased prognostic value regarding the postoperative outcome of patients (length of mechanical ventilation and in-hospital mortality), the EuroScore II can predict the length of stay in the intensive care unit as well.