52 research outputs found

    Analytic lattice cohomology of isolated curve singularities

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    We construct a lattice cohomology H(C,o)=q0Hq(C,o){\mathbb H}^*(C,o)=\oplus_{q\geq 0}{\mathbb H}^q(C,o) and a graded root R(C,o){\mathfrak R}(C,o) to any complex isolated curve singularity (C,o)(C,o). Each Hq(C,o){\mathbb H}^q(C,o) is a Z{\mathbb Z}-graded Z[U]{\mathbb Z}[U]-module. The Euler characteristic of H(C,o){\mathbb H}^*(C,o) is the delta-invariant of (C,o)(C,o). The construction is based on the multivariable Hilbert series of the multifiltration provided by valuations of the normalization. Several examples are discussed, e.g. Gorenstein curves (where an additional symmetry is established), plane curves (in particular, Newton non-degenerate ones), ordinary rr-tuples. We also prove that a flat deformation (Ct,o)t(C,0)(C_t,o)_{t\in ({\mathbb C},0)} of isolated curve singularities induces an explicit degree zero graded Z[U]{\mathbb Z}[U]-module morphism H0(Ct=0,o)H0(Ct0,o){\mathbb H}^0(C_{t=0},o)\to {\mathbb H}^0(C_{t\not=0},o), and a graded (graph) map of degree zero at the level of graded roots R(Ct0,o)R(Ct=0,o){\mathfrak R}(C_{t\not=0},o)\to{\mathfrak R}(C_{t=0},o). In the treatment of the deformation functor we need a second construction of the lattice cohomology in terms of the system of linear subspace arrangements associated with the above filtration

    A szénhidrogén-feldolgozás káreseményeihez kapcsolódó tűzvizsgálati tevékenység fejlesztési lehetőségei – 1. rész

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    A tűzvizsgálati tevékenység fontos része a katasztrófavédelem komplex rendszerének, a feltárt tűzkeletkezési okok és a megszerzett tapasztalatok visszahatnak a tűzvédelemre, az iparbiztonságra és a polgári védelemre. A szerzők hipotézise, hogy a szénhidrogén-feldolgozás során keletkezett tüzek vizsgálata merőben más szemléletet kíván, mint az élet különféle területein lefolytatott tűzvizsgálatok. A cikksorozat első részében a szerzők kérdőíves felméréssel vizsgálták a Katasztrófavédelmi Műveleti Szolgálat (a továbbiakban: KMSZ) adottságait. A szénhidrogén-feldolgozáshoz kapcsolódó tűzeseteket, tűzvizsgálatokat elemezve javaslatokat tesznek a fejlesztésre és a képzésre az egyén és a szervezet szemszögéből

    Efficacy of selective NCX inhibition by ORM-10103 during simulated ischemia/reperfusion.

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    In this study we evaluated the effects of selective Na+/Ca2+ exchanger (NCX) inhibition by ORM-10103 on the [Ca2+]i transient (CaT), action potential (AP), and cell viability in isolated canine ventricular cardiomyocytes exposed to a simulated ischemia/reperfusion protocol performed either alone (modeling moderate low-flow ischemia) or with simultaneous strophantidine challenge (modeling more severe low-flow ischemia). CaTs were monitored using a Ca2+-sensitive fluorescent dye, APs were recorded by intracellular microelectrodes, and anaerobic shifts in cellular metabolism were verified via monitoring native NADH fluorescence. Simulated ischemia increased the NADH fluorescence, reduced the amplitudes of the AP and CaT and induced membrane depolarization. APs moderately shortened, CaTs prolonged. Diastolic [Ca2+]i ([Ca2+]iD) level increased significantly during ischemia and further elevated following strophantidine application. Reperfusion normalized the NADH level, the amplitude of the AP and duration of the [Ca2+]i transient, but only partially restored action potential triangulation and the amplitude of the CaT. [Ca2+]iD decreased in untreated, but further increased in strophantidine-treated cells. 10microM ORM-10103 significantly reduced the ischemic [Ca2+]i raise in both untreated and strophantidine-treated cells. During reperfusion ORM-10103 decreased [Ca2+]i and eliminated its diastolic elevation in untreated and strophantidine-treated cardiomyocytes. Following the application of ORM-10103 the detrimental effect of ischemia/reperfusion on cell viability and the reperfusion-induced increase in AP and CaT variabilities were substantially reduced, but ischemia-induced shifts in AP morphology were barely influenced. In conclusion, selective NCX inhibition by ORM-10103 is highly effective against ischemia/reperfusion induced pathologic alterations in [Ca2+]i homeostasis, however, it fails to normalize untoward arrhythmogenic changes in AP morphology

    Műszaki kutatások és hatékony kormányzás

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    A Comparative Study of the Rapid (IKr) and Slow (IKs) Delayed Rectifier Potassium Currents in Undiseased Human, Dog, Rabbit, and Guinea Pig Cardiac Ventricular Preparations

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    To understand the large inter-species variations in drug effects on repolarization, the properties of the rapid (IKr) and the slow (IKs) components of the delayed rectifier potassium currents were compared in myocytes isolated from undiseased human donor (HM), dog (DM), rabbit (RM) and guinea pig (GM) ventricles by applying the patch clamp and conventional microelectrode techniques at 37 °C. The amplitude of the E-4031-sensitive IKr tail current measured at −40 mV after a 1 s long test pulse of 20 mV, which was very similar in HM and DM but significant larger in RM and GM. The L-735,821-sensitive IKs tail current was considerably larger in GM than in RM. In HM, the IKs tail was even smaller than in DM. At 30 mV, the IKr component was activated extremely rapidly and monoexponentially in each studied species. The deactivation of the IKr component in HM, DM, and RM measured at −40 mV. After a 30 mV pulse, it was slow and biexponential, while in GM, the IKr tail current was best fitted triexponentially. At 30 mV, the IKs component activated slowly and had an apparent monoxponential time course in HM, DM, and RM. In contrast, in GM, the activation was clearly biexponential. In HM, DM, and RM, IKs component deactivation measured at −40 mV was fast and monoexponential, while in GM, in addition to the fast component, another slower component was also revealed. These results suggest that the IK in HM resembles that measured in DM and RM and considerably differs from that observed in GM. These findings suggest that the dog and rabbit are more appropriate species than the guinea pig for preclinical evaluation of new potential drugs expected to affect cardiac repolarization

    Autotoxicitási vizsgálatok a parlagfün (Ambrosia artemisiifolia L.) = Autotoxicity Tests on the Common Ragweed (Ambrosia artemisiifolia L.)

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    Kutatásunk keretében, a parlagfű autotoxicitás vizsgálatára irányuló kísérletet állítottunk be. Ismert, hogy a parlagfű által termelt allelokemikáliák, poliacetilén-származékok a környezetükben lévő más növényfajok fejlődését gátolják. A kísérlet célja, hogy megvizsgáljuk a parlagfű toxikus anyagainak feldúsulása a talajban, szerepet játszhat-e a faj visszaszorításában a nem bolygatott területeken
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