Testing red blood cell deformability of laboratory animals by slit-flow ektacytometry in various viscosity media: Inter-species and gender differences

Ferenc Kiss,Erika Sajtos,Lili Matyas,Zsuzsanna Magyar,Istvan Furka,Iren Miko,Norbert Nemeth 한국유변학회 2010 Korea-Australia rheology journal Vol.22 No.2

Viscosity of the suspending medium can be a determinant contributor to the effective measurements of red blood cell deformability using ektacytometry. Deformability of erythrocyte is known to show inter-species and gender differences, therefore the evaluation of the effects and the standardized usage of the suspending media are important in animal experiments. For evaluating the differences using various viscosity media, we aimed to test male and female Sprague-Dawley rats and beagle dogs. Blood samples were collected and red blood cell deformability was tested by a RheoScan-D200 slit-flow ektacytometer using parallel measurements in PVP solutions at viscosity of 15, 20 and 30mPa.s. The lowest elongation index values were measured in 15mPa.s solution in both species and genders. The inter-species differences were obvious: rats had higher elongation index values. Gender differences were found only in 20 and 30mPa.s samples: in rats males, while in dogs females had better red blood cell deformability. The standard usage of PVP solutions is essential for comparative studies, because the results obtained from different viscosity PVP solutions are not comparable to each other. In Sprague-Dawley rats and beagle dogs the relatively less viscous media (<20mPa.s) may result in less informative data.

Craniophora minuscula sp. n., a new species of the genus Craniophora Snellen, 1867 (Lepidoptera: Noctuidae: Acronictinae) from Japan

Ádám Kiss,Utsugi Jinbo 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.4

In the present study, a newspecies of Craniophora Snellen, 1867, C.minuscula sp. n., is described as newto science fromJapan, during course of the investigations on the Craniophora pontica-group. The external and genitaliamorphology of both sexes is provided including the discrimination of the new species from the closely allied congeners.

The power of slit-flow ektacytometry measurements for testing normal and heat treated red blood cells using various viscosity media in laboratory animals

Ferenc Kiss,Erika Sajtos,Timea Hever,Norbert Nemeth 한국유변학회 2010 Korea-Australia rheology journal Vol.22 No.1

Red blood cell (RBC) deformability values resulted from ektacytometry tests can be influenced by the viscosity of the medium in which the RBCs are suspended for measurement. To determine the power of measurements using various viscosity media in this study we used normal and heat treated RBCs from laboratory rats and beagle dogs. A RheoScan-D200 slit-flow ektacytometer was used to measure RBC deformability. Blood samples were taken from female Sprague-Dawley rats and inbred beagle dogs. Before and after heat treatment of RBC suspensions ektacytometry tests were performed using PVP solutions at viscosity of 15, 20and 30 mPa.s. Heat treatment caused impaired RBC deformability in both species and in every PVP solution. The difference between normal and heat treated RBCs was the highest in rats, while in dogs the magnitude of change was smaller, however being significant. Well comparable and stable results were found using 30 mPa.s media. The sensitivity of RBCs for heat treatment seems to be higher in rats. The suspending PVP medium at 30 mPa.s is recommended for testing RBC deformability by ektacytometry in laboratory rats and dogs, too, because this media resulted in the most stable data when comparing normal and rigid cells.

ORGANIZATIONAL RENEWAL IN HUNGARIAN INDUSTRY AND ITS EFFECTS SINCE 1989: THE CASE OF BUDAPEST

Edit Eva Kiss The Institute of East and West Studies 1998 Global economic review Vol.27 No.2

By the end of the 1980s it had become obvious that Hungarian industry needed to be completely renewed. The organizational renewal, which began in 1989, is one of the most important component of this process. The main purposes of this study are to demonstrate the renewal through the example of Budapest, which is the most dynamically developing region of the country, and to evaluate its significant effects on the development of the whole industry.

Following-up changes in red blood cell deformability and membrane stability in the presence of PTFE graft implanted into the femoral artery in a canine model

Toth, Csaba,Kiss, Ferenc,Klarik, Zoltan,Gergely, Eszter,Toth, Eniko,Vanyolos, Katalin Peto Erzsebet,Miko, Iren,Nemeth, Norbert 한국유변학회 2014 Korea-Australia rheology journal Vol.26 No.2

It is known that a moderate mechanical stress can even improve the red blood cells' (RBC) micro-rheological characteristics, however, a more significant stress causes deterioration in the deformability. In this study, we aimed to investigate the effect of the presence of artificial graft on the RBC deformability and membrane stability in beagles. In the Control group only anesthesia was induced and in the postoperative (p.o.) period blood samplings were carried out. In the Grafted group under general anesthesia, the left femoral artery was isolated, from which a 3.5 cm segment was resected and a PTFE graft (O.D.: 3 mm) of equal in length was implanted into the gap. On the $1^{st}$, $3^{rd}$, $5^{th}$, $7^{th}$ and 14th p.o. days blood was collected the cephalic veins and RBC deformability was determined ektacytometry (LoRRca MaxSis Osmoscan). Membrane stability test consisted of two deformability measurements before and after the cells were being exposed to mechanical stress (60 or 100 Pa for 300 seconds). Compared to the Control group and the baseline values the red blood cell deformability showed significant deterioration on the $3^{rd}$, $5^{th}$ and mainly on the $7^{th}$ postoperative day after the graft implantation. The membrane stability of erythrocyte revealed marked inter-group difference on the $3^{rd}$, $5^{th}$ and $7^{th}$ day: in the Grafted group the deformability decreased and during the membrane stability test smaller difference was observed between the states before and after shearing. We concluded that the presence of a PTFE graft in the femoral artery may cause changes in RBC deformability in the first p.o. week. RBC membrane stability investigation shows a lower elongation index profile for the grafted group and a narrowed alteration in the deformability curves due to mechanical stress.

A Method to Robustify Exact Linearization Against Parameter Uncertainty

Na Wang,Bálint Kiss 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.10

This paper addresses the issue of uncertain parameters in the case of the control of nonlinear systems which are exact linearizable by state feedback. It is shown that the linearizing feedback may be complemented by an additional obustifying compensator, designed to ensure robust stability and performance against the uncertainty of some model parameters. This allows to bridge two state-of-the-art design methodologies such as exact linearization and robust control synthesis. Exact linearization allows the transformation of nonlinear dynamics into linear ones by an eventually dynamic state feedback and by a change of coordinates. However, due to the uncertain nature of some model parameters, their nominal values used in the transformation may be different from their real values. This parameter misfit implies that the resulting transformed dynamics may still include non-linearities or may be a linear system, but different from the one that results for the nominal parameter values. The paper proposes a procedure to cover the uncertainties remaining after exact linearization and to design an additional linear compensator, denoted by K(s), to ensure robust performance and stability. The design of the compensator K(s) involves standard H∞ techniques, based on an output multiplicative uncertainty structure. The weighting matrices of the output multiplicative structure are obtained such that they cover a model set obtained by linearizing the transformed nonlinear system over a sufficiently fine grid above the uncertain parameter range. The suggested approach is illustrated by multiple (SISO and MIMO) examples, including a two-degrees-of-freedom robotic arm. It is shown by simulation that the additional robustifying compensator may stabilize the system for parameter values that would result in unstable behavior without its application and may also result in a better tracking performance.

Stabilization of HIV/AIDS model by receding horizon control

A. M. Elaiw,K. Kiss,M. A. L Caetano 한국전산응용수학회 2005 Journal of applied mathematics & informatics Vol.18 No.1-2

This work concerns the stabilization of uninfected steady state of an ordinary differential equation system modeling the interaction of the HIV virus and the immune system of the human body. The control variable is the drug dose, which, in turn, affects the rate of infection of CD4+ T cells by HIV virus. The feedback controller is constructed by a variant of the receding horizon control (RHC) method. Simulation results are discussed.

STABILIZATION OF HIV / AIDS MODEL BY RECEDING HORIZON CONTROL

ELAIW, A. M.,KISS, K.,L CAETANO, M. A. 한국전산응용수학회 2005 Journal of applied mathematics & informatics Vol.18 No.1

This work concerns the stabilization of uninfected steady state of an ordinary differential equation system modeling the interaction of the HIV virus and the immune system of the human body. The control variable is the drug dose, which, in turn, affects the rate of infection of $CD4^{+}$ T cells by HIV virus. The feedback controller is constructed by a variant of the receding horizon control (RHC) method. Simulation results are discussed.

An IMS-based service platform for the next-generation wireless networks

Jun, Andrew Do-Sung,Kiss, G.,Agrawal, H.,Park, Hyunseo,Kang, Sookyang,Sihn, K.,Kim, DaeSik Institute of Electrical and Electronics Engineers 2006 IEEE communications magazine Vol.44 No.9

Following-up changes in red blood cell deformability and membrane stability in the presence of PTFE graft implanted into the femoral artery in a canine model

Csaba Toth,Ferenc Kiss,Zoltan Klarik,Eszter Gergely,Eniko Toth,Katalin Peto,Erzsebet Vanyolos,Iren Miko,Norbert Nemeth 한국유변학회 2014 Korea-Australia rheology journal Vol.26 No.2

It is known that a moderate mechanical stress can even improve the red blood cells’ (RBC) micro-rheologicalcharacteristics, however, a more significant stress causes deterioration in the deformability. In thisstudy, we aimed to investigate the effect of the presence of artificial graft on the RBC deformability andmembrane stability in beagles. In the Control group only anesthesia was induced and in the postoperative(p.o.) period blood samplings were carried out. In the Grafted group under general anesthesia, the leftfemoral artery was isolated, from which a 3.5 cm segment was resected and a PTFE graft (O.D.: 3 mm)of equal in length was implanted into the gap. On the 1st, 3rd, 5th, 7th and 14th p.o. days blood was collectedthe cephalic veins and RBC deformability was determined ektacytometry (LoRRca MaxSis Osmoscan). Membrane stability test consisted of two deformability measurements before and after the cells werebeing exposed to mechanical stress (60 or 100 Pa for 300 seconds). Compared to the Control group andthe baseline values the red blood cell deformability showed significant deterioration on the 3rd, 5th andmainly on the 7th postoperative day after the graft implantation. The membrane stability of erythrocyterevealed marked inter-group difference on the 3rd, 5th and 7th day: in the Grafted group the deformabilitydecreased and during the membrane stability test smaller difference was observed between the statesbefore and after shearing. We concluded that the presence of a PTFE graft in the femoral artery maycause changes in RBC deformability in the first p.o. week. RBC membrane stability investigation showsa lower elongation index profile for the grafted group and a narrowed alteration in the deformabilitycurves due to mechanical stress.