A covering array CA(N ; t, k, v) is anN×k array on v symbols such that everyN×t subarray contains as a row each t-tuple over the v symbols at least once. The minimum N for which a CA(N ; t, k, v) exists is called the covering array number of t, k, and v, and it is denoted by CAN(t, k, v). In this work we prove that if exists CA(N ; t+ 1, k + 1, v) it can be obtained from the juxtaposition of v ...

in this study, nutrition, nutrient return and nutrient retranslocation were compared between two stands of alnus subcordata (n-fixing tree) and taxodium distichum (coniferous deciduous tree), planted on a weak drained soil in north of iran (tashbandan, amol). in each tree stand, n, p, k, ca and mg concentration of fresh and senescent leaves and soil were measured. the concentrations of n and mg...

The effects of histamine on the membrane potential and currents of human glioblastoma (GL-15) cells were investigated. In perforated whole cell configuration, short (3 s) applications of histamine (100 microM) hyperpolarized the membrane by activating a K(+)-selective current. The response involved the activation of the pyrilamine-sensitive H(1) receptor and Ca(2+) release from thapsigargin-sen...

the essential nutrients in the pharmacological plants play a significant role in the remedy of illnesses but, these elements at high levels; can also be dangerous and toxic. the aim of this study was to determine the concentration of macro (mg, ca, p, and k) and micro (cu, zn, fe and mn) essential elements in seven indigenous pharmacological plants growing in fars province, southern iran. they ...

Two recent studies reported that Na-Ca exchange in the outer segments of tiger salamander rod photoreceptors (Cervetto, L., Lagnado, L., Perry, R. J., Robinson, D. W., and McNaughton, P. A. (1989) Nature 337, 740-743) and of bovine rod photoreceptors (Schnetkamp, P. P. M., Basu, D. K., and Szerencsei, R. T. (1989) Am. J. Physiol. 257, C153-157) requires and transports K+ in a 4Na/(1Ca+1K) stoic...

the effects of salinity and supplied calcium chloride on growth and leaf ions concentration of tomato (lycopersicon esculentum l.) were investigated in gorgan, iran. a factorial experiment was conducted based on rcbd with four nacl levels (0, 50, 100, and 150 mm) and four cacl2 levels (0, 100, 200 and 300 mg l-1). data of growth, yield and leaf’s ca, k, and na content were subjected to analyze ...

Carbon monoxide (CO) is a gaseous vasodilator produced by many cell types, including endothelial and smooth muscle cells. The goal of the present study was to investigate signaling mechanisms responsible for CO activation of large-conductance Ca(2+)-activated K(+) (K(Ca)) channels in newborn porcine cerebral arteriole smooth muscle cells. In intact cells at 0 mV, CO (3 microM) or CO released fr...