The function of adult neurogenesis in the dentate gyrus is not yet completely understood, though many competing theories have attempted to explain the function of these newly -generated neurons. Most theories give adult neurogenesis a role in aiding known hippocampal/dentate gyrus functions. Other theories offer a novel role for these new cells based on their unique physiological qualities, such as their low excitability threshold. Many behavioral tests have been used to test these theories, but results have been inconsistent and often contradictory. Substantial variability in tests and protocols may be at least partially responsible for the mixed results. On the other hand, conflicting results arising from the same tests can serve as aids in elucidating the function of adult neurogenesis. Here, we offer a hypothesis that considers the cognitive nature of tasks commonly used to assess the function of adult neurogenesis, and introduce a dichotomy between tasks focused on discrimination vs. generalization. We view these two aspects as opposite ends of the continuous spectrum onto which traditional tests can be mapped. We propose that high neurogenesis favors behavioral discrimination while low adult neurogenesis favors behavioral generalization of a knowledge or rule. Since many tasks require both, the effects of neurogenesis could be cancelled out in many cases. Although speculative, we hope that our view presents an interesting and testable hypothesis of the effect of adult neurogenesis in traditional behavioral tasks. We conclude that new, carefully designed behavioral tests may be necessary to reach a final consensus on the role of adult neurogenesis in behavior., A. Pistikova, H. Brozka, A. Stuchlik., and Obsahuje bibliografii
Purification of quartz using an environment-friendly method is important in the contaminants removal. This paper presents advanced method based on calcination pretreatment combined with ultrasound-assisted leaching, for removing iron impurities from industrial quartz. The solvent used is a mixture comprised by diluted hydrochloric acid and oxalic acid. The effects of experimental parameters were investigated and the purification mechanism was discussed using particle size analyzer, scanning electron microscope and polarized light microscope. SiO2 content of concentrate could be increased from 99.6828% to 99.9047%, which achieved 3N level high purity quartz, and Fe2O3 content reduced from 0.0857% to 0.0223%, under the optimal conditions, i.e., calcination temperature of 900 °C, holding time of 2 h, oxalic acid concentration of 10 g/L, hydrochloric acid concentration of 5%, liquid solid ratio of 5, leaching temperature of 60 °C, ultrasound power of 400 W and treatment time of 30 min. Compared to conventional method, the proposed method significantly accelerates the leaching process and increases the iron removal rate. At the same time, the method also can remove gas-liquid inclusions. and Yang Changqiao, Li Suqin, Bai Jiaxing, Han Shuaishuai.
The article deals with the use of different types of connectors in the adversative complex phrases in Old Church Slavonic and their Greek parallels. The most common and most frequent conjuntions are a, nž, and to a certain extent obače, whereas the particle že is mostly defined as adversative by the semantics of the clauses. In some manuscripts from the 18th and 19th centuries appart from the use of no and a, examples of adversative sentences with the conjuctions ami and tuku are frequent, which are common also in Standard Macedonian (but ami mostly in dialects). The conjuction tuku has developed from the adverb tolku and the conjunction ami is taken from the Greek vernacular ami. The use of conjunctions from other languages - ami from Greek and ama from Turkish which had a significant influence on the spoken (Slavic) language in Macedonia vis-à-vis the language used in the Old Church Slavonic manuscripts shows that it was common to accept a foreign language construction. However, it should be mentioned that both conjunctions in Standard Macedonian are used as a kind of stylistic specifity, usually in colloquial style. The development and use of new conjunctions could also be explained by the phonemic characteristic of the conjuntion nž, to lose the nasal and thus to become not expressive enough as adversative.
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