Nemlokális kontinuummechanika konstitutiv egyenletei, azok alkalmazása a nemlineáris hullám stabilitásvizsgálatban és a biomechanikában az érfal modellezésére = Constitutive equations of nonlocal continuum mechanics and their application on investigation of wave stability and in biomechanics on modelling of blood-vessel

A nemlokális testek anyagtörvényeinek a szakcikkekben 8-féle felépítési módját találtuk. A lehetőségek viszonylag nagy száma miatt arra következtettünk, hogy a nemlokális testek anyagtörvényének nincs elfogadott alakja. A felvetett 8 felépítési módból a kutatás során kettőt vizsgáltunk részletesen, mégpedig a Mindlin-féle anyag esetét és a hullámdinamikai anyagtörvény meghatározási módot. A kapott eredmények arra vezetnek, hogy a feszültség tenzor egy funkcionál Lagrange deriváltja. Bevezettük a feltételes Lagrange deriváltat, amely biztosítja a hullámdinamikai elmélet által megkövetelt gyorsuláshullám létezését. Az ilyen Lagrange derivált a nemlokális test általánosabb alakjat értelmezi. Az anyagi instabilitás kutatása a dinamikai rendszerek elméletében kidolgozott módszerek alkalmazását teszi lehetővé. A feladatban ilyen módon a Ljapunov-féle vizsgálati módszerek felhasználásával az anyagtörvény újabb lehetséges változói jelennek meg azonfelül, hogy tisztázható a bifurkációelmélet felosztásainak egyértelmű meghatározása, és ezek kapcsolata a nemlokális anyagtörvényre vonatkozóan. A nem-lokális anyagok termomechanikai vizsgálata az irreverzibilis folyamatok esetén a termodinamikai és a mechanikai hullámok külön-külön és együttes megjelenését is eredményezi. A kétrétegű vastagfalú cső alkalmas modell a meszesedő vérerek szilárdsági megítélésére. A modellt finomítottuk a nemlokális testek esetére, amely a meszesedő erek szerkezetének pontosabb figyelembevételét tette lehetővé. | In the literature of the constitutive equations of nonlocal bodies eight types of possible constructions can be found. The large number of possibilities implies that there is no generally accepted form for nonlocal bodies. In the studies performed we consider two out of the eight, namely the case of Mindlin's material and the use of the wave dynamical method. The results show that the stress tensor is a Lagrange derivative of a functional. By introducing the conditional Lagrange derivative the existence of the acceleration wave is obtained. Such wave is necessary for the wave dynamical method. This Lagrange derivative defines a more general form of the nonlocal body. The investigation of material instability enables us to apply the tools of the theory of dynamical systems. I such a way by using Lyapunov's methods additional possible variables of the constitutive equation can be detected. Moreover, we can clarify the connection of the classification of bifurcation theory and the nonlocal constitutive equations. In case of irreversible processes the thermo-mechanical investigation of nonlocal bodies results the appearance of thermodynamic and mechanical waves as both separate and coupled phenomena. The thick walled tube of dual layer is an appropriate model for studying blood vessels under arteriosclerosis. This model can be refined for nonlocal bodies, which enables us to get a more exact consideration for the structure of the arteriosclerosis effect

Inhaler Competence and Patient Satisfaction with Easyhaler: Results of Two Real-Life Multicentre Studies in Asthma and COPD.

OBJECTIVE: The aim of this study was to investigate patients' inhaler competence and satisfaction with the Easyhaler(R) dry powder inhaler. DESIGN: Two open, uncontrolled, non-randomised studies. SETTING: Real life based on patients attending 56 respiratory clinics in Hungary. PARTICIPANTS: Patients with asthma or chronic obstructive pulmonary disease (COPD) (n = 1016). INTERVENTION: In a 3-month study, adult patients (age range 18-88 years; n = 797) received twice-daily inhalations of formoterol via Easyhaler(R), and in a consequential study (from one visit to another, with 3-12 months in-between) children and adolescents (age range 4-17 years; n = 219) received salbutamol via Easyhaler(R) as needed. MAIN OUTCOME MEASURES: Control of six Easyhaler(R) handling steps and patients' satisfaction with Easyhaler(R) based on questionnaires. RESULTS: Correct performances (minimum and maximum of the six steps) were noticed after one demonstration in 92-98 % of the adults, 87-99 % of the elderly, 81-96 % of the children and 83-99 % of the adolescents. These figures had markedly increased at the last visit. Repeat instructions were necessary in 26 % of the cases. Investigators found Easyhaler(R) easy to teach in 87 % of the patients and difficult in only 0.5 %. Patients found Easyhaler(R) easy to learn and use, and the patients' (and parents') satisfaction with the inhaler was very high. Lung function values [forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF)] improved statistically significantly during the studies, indicating good inhaler competence and treatment adherence. CONCLUSION: Investigators found Easyhaler(R) easy to teach and patients found it easy to use, and their satisfaction with the device was high

Enantioseparation of amino alcohol analogs possessing 1,2,3,4-tetrahydroisoquinoline skeleton and its derivatives using polysaccharide-based chiral stationary phases

The stereoisomers of 1,2,3,4-tetrahydroisoquinoline amino alcohol analogues were directly separated on modified cellulose based chiral stationary phases. The effects of the mobile phase composition, the structure of the analytes and temperature on the separations were investigated. Experiments were performed at constant mobile phase compositions with varying temperature in order to calculate thermodynamic parameters from plots of ln α versus 1/T. Some mechanistic aspects of the chiral recognition process are discussed with respect to the structures of the analytes

Enantioseparation of cyclic β-amino acids on ion-exchangerbased chiral stationary phases

In the present work a direct HPLC method is described for the separation of the stereoisomers of the ampholytic non-methylated, N-methyl-, N-dimethyl- and N-amidino protected cyclic βamino acids through the application of novel Cinchona alkaloid and sulfonic acid-based zwitterionic chiral stationary phases Chiralpak ZWIX(+)™ and ZWIX(-)™. The enantioseparations were carried out in polar-ionic mobile phase mode in the temperature range 5–40 °C. The effects of the composition of the bulk solvent, the acid and base additive, the temperature, the structures of the ampholytic analytes on the separations were investigated

High-performance liquid chromatographic study on the enantioseparation of fluorine containing cyclic amino acid derivatives

The stereoisomers of several fluorinated cyclic β 3 -amino acid derivatives and their nonfluorinated counterparts were separated on chiral stationary phases containing as chiral selectors cellulose tris-(3,5-dimethylphenyl carbamate), cellulose tris-(3-chloro-4-methylphenyl carbamate), cellulose tris-(4-methylbenzoate), cellulose tris-(4-chloro-3-methylphenyl carbamate), amylose tris-(3,5-dimethylphenyl carbamate) or amylose tris-(5-chloro-2-methylphenyl carbamate). The enantioseparations were carried out in normal-phase mode with n-hexane/alcohol/alkylamine mobile phases in the temperature range 5–40 °C. The effects of the mobile phase composition, the nature and concentration of the alcohol and alkylamine additives, the structures of the analytes and temperature on the separations were investigated

Increased Short-Term Beat-To-Beat Variability of QT Interval in Patients with Acromegaly.

Cardiovascular diseases, including ventricular arrhythmias are responsible for increased mortality in patients with acromegaly. Acromegaly may cause repolarization abnormalities such as QT prolongation and impairment of repolarization reserve enhancing liability to arrhythmia. The aim of this study was to determine the short-term beat-to-beat QT variability in patients with acromegaly. Thirty acromegalic patients (23 women and 7 men, mean age+/-SD: 55.7+/-10.4 years) were compared with age- and sex-matched volunteers (mean age 51.3+/-7.6 years). Cardiac repolarization parameters including frequency corrected QT interval, PQ and QRS intervals, duration of terminal part of T waves (Tpeak-Tend) and short-term variability of QT interval were evaluated. All acromegalic patients and controls underwent transthoracic echocardiographic examination. Autonomic function was assessed by means of five standard cardiovascular reflex tests. Comparison of the two groups revealed no significant differences in the conventional ECG parameters of repolarization (QT: 401.1+/-30.6 ms vs 389.3+/-16.5 ms, corrected QT interval: 430.1+/-18.6 ms vs 425.6+/-17.3 ms, QT dispersion: 38.2+/-13.2 ms vs 36.6+/-10.2 ms; acromegaly vs control, respectively). However, short-term beat-to-beat QT variability was significantly increased in acromegalic patients (4.23+/-1.03 ms vs 3.02+/-0.80, P<0.0001). There were significant differences between the two groups in the echocardiographic dimensions (left ventricular end diastolic diameter: 52.6+/-5.4 mm vs 48.0+/-3.9 mm, left ventricular end systolic diameter: 32.3+/-5.2 mm vs 29.1+/-4.4 mm, interventricular septum: 11.1+/-2.2 mm vs 8.8+/-0.7 mm, posterior wall of left ventricle: 10.8+/-1.4 mm vs 8.9+/-0.7 mm, P<0.05, respectively). Short-term beat-to-beat QT variability was elevated in patients with acromegaly in spite of unchanged conventional parameters of ventricular repolarization. This enhanced temporal QT variability may be an early indicator of increased liability to arrhythmia

Enantiomer separation of chiral tetrahydroisoquinoline analogs by supercritical fluid chromatography and high-performance liquid chromatography

1,2,3,4-Tetrahydroisoquinoline and its analogs have received serious attention from synthetic and medicinal chemists lately. These compounds are core structural elements present in several peptide-based drugs and form an important part of various biologically active compounds. The optical purity of potential pharmacons has an immense importance during chiral drug development. Hence, there is a need for efficient separation methods of chiral 1,2,3,4-tetrahydroisoquinoline analogu. Selection of suitable chromatography technique is the first and the most difficult step in the method development. In our study we investigated the similarities and differences between liquid chromatography (LC) and supercritical fluid chromatography (SFC) methods on the bases of the separation of six 1,2,3,4- tetrahydroisoquinoline analogs and three structurally closely related enantiomer pairs. Nine chiral stationary phases (CSPs) including quinidine- or quinine-based zwitterionic and polysaccharides based selectors were applied in HPLC and SFC mode to evaluate the chiral separation of the nine structurally related analogs. HPLC measurements were carried out in normal phase mode on seven polysaccharide-based CSPs and in polar ionic mode on the two zwitterionic CSPs. In normal phase LC mode, the effects of the composition of the bulk solvent and the natures of the alcohol and amine additives, while in SFC mode the effects of the content and natures of alcohol modifier, the counter-ion concentration and the structures of the analytes were investigated. The separations of the stereoisomers were optimized in both SFC and LC modes. The effect of column temperature on the separation was also studied to gain deeper understanding of the complex thermodynamic processes taking part in the enantiorecognition. Thermodynamic parameters were calculated applying van't Hoff plots and the results showed that on the polysaccharide-based columns in both normal phase LC mode and in SFC mode mostly enthalpically-driven enantiomer separations were dominant. However, in some cases, entropically-driven separations were also observed. The NP and SFC chromatographic mode exhibited different effectiveness in the separation of stereoisomers: separation was more efficient in SFC mode, however, sometimes very high resolutions were achieved in NP LC mode, which shows the different suitability of the SFC mode

Függvényegyenletek és egyenlőtlenségek = Functional equations and inequalities

A kutatásban 19 fő vett részt. A kutatócsoport tagjai 2003 és 2006 között 3 könyvet, 103 referált nemzetközi folyóiratban, vagy konferenciakiadványban megjelent tudományos dolgozatot, további 15 közlésre elfogadott dolgozatot, 6 PhD, 1 habilitációs és 2 MTA doktori értekezést készítettek, továbbá 208 tudományos előadást tartottak. A nem-iteratív függvényegyenletek regularitáselméletének monografikus összefoglalását adja Járai Antal 2005-ben a Kluwer kiadónál megjelent könyve. Ez mű az elmúlt két évtizedben a kutatócsoport által elért eredményeket egységes szemléletmódban tárgyalja és új alkalmazásokat is bemutat. Az iteratív függvényegyenletek és az un. invariancia-egyenlet regularitási vizsgálataiban is számos új módszer és eredmény született. A spektrálszintézis és spektrálanalízis kutatásában döntő áttörést hoztak Székelyhidi László kutatásai. Kiderült, hogy bizonyos diszkrét Abel-csoportokon a spektrálszintézis nem teljesülhet, ezzel egy több évtizede fennálló sejtés is megdőlt. A témakör elméletének alapvető és lezáró eredményeit tartalmazó monográfia 2006-ban a Springer kiadónál jelent meg. A lineáris operátorok és függvényterek megőrzési problémáinak összefoglalását adja Molnár Lajosnak a Springer Lecture Notes sorozatában 2007-ben megjelent könyve. A Hadamard-egyenlőtlenség magasabbrendű általánosításainak és a közelítőleg konvex függvényeknek a vizsgálata is számos új fejleményet hozott. | The research was carried out by 19 researchers. The members of the research team published 3 books, 103 research papers in refereed journals or conference proceedings, 15 papers accepted for publication, furthermore, 6 PhD, 1 habilitation and 2 DSc dissertations in the period 2003-2006. The monographic summary of the regularity theory of non-iterative functional equations was published by Antal Járai at the Kluwer Academic Publishers. This work treats the results of the research team obtained in the last two decades in a unified manner and also presents new applications. The investigation of the regularity problems of the iterative functional equations and the so-called invariance equation lead to a number of new methods and results. The investigation of spectral synthesis and spectral analysis reached a breakthrough point due to László Székelyhidi's results. It turned out that the spectral synthesi fails to hold on certain discrete Abelian groups. This result negatively answered a longstanding conjecture. The basic and key results of the subject were summarized in a book published by Springer Verlag. A book by Lajos Molnár, published in the Lecture Notes of Springer in 2007, summarizes the results obtained on preserver problems of linear operators and functions spaces. There were also new and interesting developments in the investigation of higher-order generalizations of the Hadamard inequality and approximately convex functions