AMP -activated protein kinase (AMPK) plays a role in metabolic regulation under stress conditions, and inadequate AMPK signaling may be also involved in aging process. The aim was to find out whether AMPK α 2-subunit deletion affects heart function and ische mic tolerance of adult and aged mice. AMPK α 2 -/- (KO) and wild type (WT) female mice were compared at the age of 6 and 18 months. KO mice exhibited subtle myocardial AMPK α 2-subunit protein level, but no difference in AMPK α 1-subunit was detected between the strains. Both α 1- and α 2-subunits of AMPK and their phosphorylation decreased with advanced age. Left ventricular fractional shortening was lower in KO than in WT mice of both age groups and this difference was maintained after high-fat feeding. Infarct size induced by global ischemia/reperfusion of isolated hearts was similar in both strains at 6 months of age. Aged WT but not KO mice exhibited improved ischemic tolerance compared with the younger group. High-fat feeding for 6 months during aging abolished the infarct size-reduction in WT without affecting KO animals; nevertheless, the extent of injury remained larger in KO mice. The results demonstrate that adverse effects of AMPK α 2-subunit deletion and high-fat feeding on heart function and myocardia l ischemic tolerance in aged female mice are not additive., K. Slámová, F. Papoušek, P. Janovská, J. Kopecký, F. Kolář., and Obsahuje bibliografii
Accumulating evidence indicates that hypertension is associated with "ion channel remodeling" of vascular smooth muscle cells (VSMCs). The objective of this study was to determine the effects of exercise intensity/volume on hypertension-associated changes in large-conductance Ca2+-activated K+ (BKCa) channels in mesenteric arteries (MAs) from spontaneously hypertensive rats (SHR). Male SHRs were randomly assigned to three groups: a low-intensity aerobic exercise group (SHR-L: 14 m/min), a moderate-intensity aerobic exercise group (SHR-M: 20 m/min), and a sedentary group (SHR). Age-matched Wistar-Kyoto rats (WKYs) were used as normotensive controls. Exercise groups completed an 8-week exercise program. Elevation of the α and β1 proteins was unequal in MA myocytes from SHRs, with the β1 subunit increasing more than the α subunit. BKCa contribution to vascular tone regulation was higher in the myocytes and arteries of SHRs compared to WKYs. SHR BKCa channel subunit protein expression, β1/α ratio, whole cell current density and single-channel open probability was also increased compared with WKYs. Aerobic exercise lowered systemic blood pressure and normalized hypertension-associated BKCa alterations to normotensive control levels in the SHRs. These effects were more pronounced in the moderate-intensity group than in the low-intensity group. There is a dose-effect for aerobic exercise training in the range of low to moderate-intensity and accompanying volume for the correction of the pathological adaptation of BKCa channels in myocytes of MAs from SHR., Y. Zhang, Y. Chen, L. Zhang, N. Lu, L. Shi., and Obsahuje bibliografii
The paper studies applications of C*-algebras in geometric topology. Namely, a covariant functor from the category of mapping tori to a category of AF-algebras is constructed; the functor takes continuous maps between such manifolds to stable homomorphisms between the corresponding AF-algebras. We use this functor to develop an obstruction theory for the torus bundles of dimension 2, 3 and 4. In conclusion, we consider two numerical examples illustrating our main results., Igor Nikolaev., and Obsahuje seznam literatury
In this paper it is proved that an abelian lattice ordered group which can be expressed as a nontrivial lexicographic product is never affine complete.
Let $\Delta $ and $H$ be a nonzero abelian linearly ordered group or a nonzero abelian lattice ordered group, respectively. In this paper we prove that the wreath product of $\Delta $ and $H$ fails to be affine complete.
Identities for the curvature tensor of the Levi-Cività connection on an almost para-cosymplectic manifold are proved. Elements of harmonic theory for almost product structures are given and a Bochner-type formula for the leaves of the canonical foliation is established.
In his book Individuals P. F. Strawson writes that ‘both the Cartesian and the no-ownership theorists are profoundly wrong in holding, as each must, that there are two uses of ''I'', in one of which it denotes something which it does not denote in the other’ (p. 98). I think, by contrast, that there is a defensible ''Cartesian materialist'' sense, which Strawson need not reject, in which I (=df. the word ''I'' or the concept i) can and does denote two different things, and which is nothing like the flawed Wittgensteinian distinction between the use of I ''as object'' and the use of I ''as subject''. I don’t argue directly for the ''two uses'' view, however. Instead I do some preparatory work. First I criticize one bad (Wittgensteinian or ''Wittgensteinian'') argument for the ''only one use of I'' view. Then I offer a phenomenological description of our everyday experience of ourselves that leads to an attack on ''corporism''-the excessive focus on the body in present-day analytic philosophy of mind., Ve své knize Jednotlivci PF Strawson píše, že ,,jak karteziánští, tak teoretici bez vlastnictví jsou naprosto špatní v držení, protože každý musí, že existují dvě použití,, I '', v jednom z nich označuje něco, co neoznačuje v ostatních “(str. 98). Naproti tomu si myslím, že existuje obranný ,,karteziánský materialistický'' smysl, který Strawson nemusí odmítat, ve kterém I (= df. Slovo ,,I'' nebo pojem i) lze a označuje dvě různé věci, a které není nic takového jako chybný Wittgensteinův rozdíl mezi použitím I 'jako objektu' a použitím I 'jako předmětu'. Nehledám však přímo na pohled ,,dvou použití''. Místo toho dělám nějaké přípravné práce. Nejprve kritizuji jeden špatný (Wittgensteinův nebo ,,Wittgensteinův'') argument pro ,,jediné použití I''. Pak nabízím fenomenologický popis našich každodenních zkušeností, které vedou k útoku na ,,korporismus'' - nadměrné zaměření na tělo v současné analytické filozofii mysli., and Galen Strawson
In this paper, I combine an exposition of the historical development of sociology and the philosophy of science from the era of grand theories onwards, with an explication as to why the grand theories have failed. First, I trace some parallels in the history of each of the disciplines. After presenting their chronological development, I scrutinize the metatheoretical findings about the disciplines and examine the main ontological and epistemic reasons why attempts at these general theories or frameworks have not succeeded. Among them are the lack of a universal methodology and of a theoretical core, together with the impossibility of achieving a common objective view. On this basis I conclude that general theories or frameworks are not achievable in principle. As it turns out, however, some contemporary social theorists and philosophers still harbor hopes that they can be successfully formulated, or at the least do not rule out such a possibility. Thus, in closing, I argue that the critical points can also be applied to these latest attempts, as the call for grand theories or frameworks has never ceased and returns regularly with each new generation of social theorists and philosophers of science. and Tento článek kombinuje přehled historického vývoje sociologie a filosofie vědy od období „velkých“ teorií s výkladem toho, proč tyto teorie selhaly. V první části sleduji historické paralely v obou těchto disciplínách. Po představení jejich chronologického vývoje analyzuji metateoretické závěry, které z toho vyplývají, a zkoumám hlavní epistemické a ontologické důvody, proč neuspěly – mezi nimi chybějící univerzální metodologii a teoretické jádro i nemožnost dosažení objektivního náhledu. Z toho vyvozuji závěr, že velké teorie nejsou principiálně zkonstruovatelné. Ukazuje se nicméně, že některé současní sociální teoretici i filosofové vědy stále doufají, že takové teorie nebo rámce mohou být úspěšně formulovány, nebo přinejmenším takovou možnost nevylučují. V závěru argumentuji, že kritika vznesená vůči těmto dřívějším teoriím může být uplatněna i na tyto aktuální pokusy. Ukazuje se totiž, že volání po těchto teoriích a rámcích nikdy úplně nepřestalo a opakuje se s každou novou generací sociálních vědců a filosofů vědy.
This paper addresses the so-called ''truthmaker problem'' or ''grounding problem'' for presentism. In section 1, I set the stage by introducing presentism and the truthmaker problem. In section 2, I consider a proposed solution to it, which I call the ''laws of nature proposal'' (LNP), recently defended by Markosian (2013). I argue that LNP fails as a solution to the truthmaker problem because it does not meet a constraint that is generally taken as constitutive of it: that the entities doing truthmaker work should be categorical. Then, in section 3, I discuss the prospects of abandoning this ''categoricity constraint''. The conclusion of this discussion is that the presentist should be allowed to such a move. This, however, is not completely good news for the friends of LNP, since the abandonment of the ''categoricity constraint'' opens the door to simpler solutions, like what is often called ''Lucretianism''., Tento článek se zabývá tzv. ,,Problémem pravdy'' nebo ,,problémem uzemnění'' pro presentismus. V oddíle 1 jsem stanovil etapu zavedením presentismu a problematiky pravdy. V oddíle 2 se zabývám navrhovaným řešením, které nazývám ,,zákony o přírodním návrhu'' (LNP), které nedávno obhajoval Markosian (2013). Domnívám se, že LNP selhává jako řešení problému s pravdivostí, protože nesplňuje omezení, které je obecně považováno za jeho konstitutivní: že subjekty provádějící práci s pravdivostí by měly být kategorické. Poté v oddíle 3 diskutuji vyhlídky na opuštění této ,,kategorie omezení''. Závěrem této diskuse je, že by měl být moderátorovi umožněn takový krok. To však není pro přátele LNP úplně dobrá zpráva, protože opuštění ,,kategorického omezení'' otevírá dveře k jednodušším řešením, jako je to, co se často nazývá ''lykretianismus''., and Pablo Rychter