Cadmium is a heavy metal causing toxicity especially in kidney
cells. The toxicity is linked also with enhanced oxidative stress
leading to cell death. On the other hand, our recent experiments
have shown that an increase of total intracellular dehydrogenases
activity can also occur in kidney cells before declining until cell
death. The aim of the present study, therefore, was to evaluate
this transient enhancement in cell viability after cadmium
treatment. The human kidney HK-2 cell line was treated with
CdCl2 at concentrations 0-200 µM for 2-24 h and intracellular
dehydrogenase activity was tested. In addition, we measured
reactive oxygen species (ROS) production, glutathione levels,
mitochondrial membrane potential, and C-Jun-N-terminal kinase
(JNK) activation. We found that significantly increased
dehydrogenase activity could occur in cells treated with 25, 100,
and 200 µM CdCl2. Moreover, the results showed an increase in
ROS production linked with JNK activation following the
enhancement of dehydrogenase activity. Other tests detected
no relationship with the increased in intracellular dehydrogenase
activity. Hence, the transient increase in dehydrogenase activity
in HK-2 cells preceded the enhancement of ROS production and
our finding provides new evidence in cadmium kidney toxicity.
This paper presents a new technique for fingerprint image matching in biometric security applications, based on the hybrid of Neural Network and Delaunay Triangulation methodology. The Delaunay triangulation of the minutiae set is transformed to a set of points in the discretized space using duality. This translation results in a sampling method be acquiring which the system tolerates displacement and noise of the input image. Finally, Transiently Chaotic Associative Network (TCAN) is used to learn the obtained pattern. Experimental results show a significant improvement in the False Rejection Rate over both the traditional Delaunay Triangulation based approach and direct Neural Network application.
Amphicrossus japonicus is the first known facultatively aquatic nitidulid. The adult beetles breed in bamboo sap and subsequently enter water-filled bamboo culms. In water they breathe via a ventral air sheath held by hydrofuge pubescence. The beetles are facultative predators and hunt mosquito larvae, which they grab with their forelegs. The trend to facultative predation in Cucujoidea and the transition for beetles in general from semi-liquid decaying organic matter into water is discussed.
Central pattern generators (CPGs) play an important role in controlling rhythmic movements in vivo. Increased insight into mechanisms of CPGs can be obtained by perturbing neuron activities so as to study a range of behaviors. By applying this method, a series of simulations were performed to research different transition modes between firing patterns in a pacemaker neuron model of stomatogastric ganglion (STG). Firstly, with the perturbation of parameters in model, such as external stimulus, parameters in compartments and connection between compartments, different firing patterns and bifurcation of inter-spike intervals (ISIs) were obtained to exhibit the impact of single parameter on the transions between spiking and bursting. Moreover, perturbing two parameters gCa, Iext simultaneously induced the continuous variation of the bifurcation mode, which implied the crucial role of calcium channel in regulating the rhythm generation. Finally, a two-dimensional parameter space (gCa, Iext) was constructed by spike-counting method to capture the distribution of the firing patterns and different transition mode between them in a comprehensive aspect. In this parameter space, three basic transition modes were concluded: bifurcation ring, period-doubling mode and period-adding mode.
The distributions of the tetraploid Anthoxanthum odoratum and diploid A. alpinum were first studied in the Krkonoše Mts (part of the Sudetes Mts) to find the transition zone where both species occur together and then their ecological requirements in this zone were determined. The distribution was studied at two spatial scales, geographic and local; the latter included detailed distribution at a locality level, where the relationships of both species to plant communities were investigated. The zone where the overlap occurs is between 800–1290 m a.s.l. Anthoxanthum alpinum is able to descend to even lower altitudes, where it grows in vegetation dominaned by Nardus stricta. The species commonly occur in a fine mosaic of plant communities of Polygono-Trisetion (A. odoratum), Nardion (A. alpinum) or Nardo-Agrostion tenuis (both species). Anthoxanthum alpinum also occurs in areas that are currently not in direct contact with either alpine or subalpine vegetation (the Rýchory ridge, Černá hora Mt).
In this paper, we give necessary and sufficient conditions on $(p_n)$ for $| R,p_n| _k$, $k\ge 1$, to be translative. So we extend the known results of Al-Madi [1] and Cesco $\left[ 4\right] $ to the case $k>1$.