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Systemic hyperglycemia and hypercapnia severely aggravate ischemic brain damage when instituted prior to cerebral ischemia. An aberrant cell signaling following ischemia has been proposed to be involved in ischemic cell death, affecting protein kinase C (PKC) and the calcium calmodulin kinase II (CaMKII). Using a cardiac arrest model of global brain ischemia of 10 min duration, we investigated the

ABSTRACT— A model is described in which transient ischemia is induced in rats anaesthetized with N2O:O2 (70:30) by bilateral carotid artery clamping combined with a lowering of mean arterial blood pressure to 50 mm Hg, the latter being achieved by bleeding, or by bleeding supplemented with administration of trimetaphan or phentolamine. By the use of intubation, muscle paralysis with suxamethonium

The present study aimed to study the relation between the release of arachidonic acid (AA) and the energy state in cerebral cortices of rats during single episodes of cortical spreading depression (CSD). The changes in concentrations of AA, labile phosphate compounds [ATP, ADP, AMP, and phosphocreatine (PCr)], and glycolytic metabolites (lactate, pyruvate, glucose, and glycogen) were studied durin

Human activities and climate change affect hydrological and sedimentological characteristics within catchments. For arid and semiarid areas this induces direct negative economic and environmental consequences on society. In fact, stability in the rainfall regime and less siltation trapped in reservoirs mean more water for irrigation, water supply, and better flood control. This is especially impor

Purpose: The fluid flow in a rotating channel is obviously different from that in a stationary channel due to the existence of Coriolis force, which, in turn, enhances the heat transfer on the trailing side and reduces the heat transfer on the leading side. The purpose of this paper is to study various rib configurations combined with channel orientation on heat transfer and frictional loss in a r

Purpose: This study aims to clarify the mechanism of film hole location at the span-wise direction of an internal cooling channel with crescent ribs on the adiabatic film cooling performance, three configurations are designed to observe the effects of the distance between the center of the ellipse and the side wall(Case 1, l = w/2, Case 2, l = w/3 and for Case 3, l = w/4). Design/methodology/appro

Maps of the MT-saturation as derived in FLASH-based multi-parameter mapping (MPM) are largely corrected for effects of flip angle inhomogeneity. Here, we present a heuristic model for residual effects of B1+ that is rooted in the dynamics of macromolecule saturation. Model parameters were validated for brain tissues by variation of the MT-pulse flip angle in an established MPM protocol. White and

Purpose: The purpose of this study is to enhance the thermal performance in the labyrinth channel by different ribs shape. The labyrinth channel is a relatively new cooling structure to decrease the temperature near the trailing region of gas turbine. Design/methodology/approach: Based on the geometric similarity, a simplified geometric model is used. The k − ω turbulence model is used to close th