40 research outputs found
Egg Quality Characteristics in Autochthonous Genotypes of Chickens Raised on Macedonian Rural Farms
Egg quality characteristics of three different autochthonous chicken phenotypes (phenotype having ashy-silvery-brown leghorn laced plumage color, phenotype having light brown spangled plumage color and phenotype having black or blue plumage color) were examined. These types of chickens are mainly raised as backyard rural area flocks in the villages of R. Macedonia. The data were collected through first systematic approaches in phenotypical identification and characterisation of these autochthonous genotypes realized recently. Three small flocks of old hens collected from different villages and placed in control pens were established. No data about number of eggs/hen/year is available for the established flocks. Further investigations are needed to record productive (number of egg produced) and reproductive data. The plan was that additional, yearly production records be collected from the flock produced as offspring from established flock of old hens collected from different villages and placed in control pens. Set of 90 eggs was collected (30 eggs from each plumage phenotype) and basic egg quality parameters measured. Egg size (weight) was 50.71g for brown laced plumage phenotype, 60.48g for blue plumage phenotype and 52.6 g for light brown spangled plumage phenotype. Egg shell strength was 3965, 3628 and 3924 g/cm2 for brown laced, blue and brown spangled plumage phenotype, respectively. Light brown spangled plumage phenotype had the highest value of yolk color (10.29) and Hough Units (76.63) compared to brown laced (10.08 and 75.27) and blue (9.09 and 71.65) plumage phenotype
Generalized Chaotic Synchronizationin Coupled Ginzburg-Landau Equations
Generalized synchronization is analyzed in unidirectionally coupled
oscillatory systems exhibiting spatiotemporal chaotic behavior described by
Ginzburg-Landau equations. Several types of coupling betweenthe systems are
analyzed. The largest spatial Lyapunov exponent is proposed as a new
characteristic of the state of a distributed system, and its calculation is
described for a distributed oscillatory system. Partial generalized
synchronization is introduced as a new type of chaotic synchronization in
spatially nonuniform distributed systems. The physical mechanisms responsible
for the onset of generalized chaotic synchronization in spatially distributed
oscillatory systems are elucidated. It is shown that the onset of generalized
chaotic synchronization is described by a modified Ginzburg-Landau equation
with additional dissipation irrespective of the type of coupling. The effect of
noise on the onset of a generalized synchronization regime in coupled
distributed systems is analyzed.Comment: 12 page
Hypoxia Impairs Initial Outgrowth of Endothelial Colony Forming Cells and Reduces Their Proliferative and Sprouting Potential
Vascular homeostasis and regeneration in ischemic tissue relies on intrinsic competence of the tissue to rapidly recruit endothelial cells for vascularization. The mononuclear cell (MNC) fraction of blood contains circulating progenitors committed to endothelial lineage. These progenitors give rise to endothelial colony-forming cells (ECFCs) that actively participate in neovascularization of ischemic tissue. To evaluate if the initial clonal outgrowth of ECFCs from cord (CB) and peripheral blood (PB) was stimulated by hypoxic conditions, MNCs obtained from CB and PB were subjected to 20 and 1% O2 cell culture conditions. Clonal outgrowth was followed during a 30 day incubation period. Hypoxia impaired the initial outgrowth of ECFC colonies from CB and also reduced their number that were developing from PB MNCs. Three days of oxygenation (20% O2) prior to hypoxia could overcome the initial CB-ECFC outgrowth. Once proliferating and subcultured the CB-ECFCs growth was only modestly affected by hypoxia; proliferation of PB-ECFCs was reduced to a similar extent (18–30% reduction). Early passages of subcultured CB- and PB-ECFCs contained only viable cells and few if any senescent cells. Tube formation by subcultured PB-ECFCs was also markedly inhibited by continuous exposure to 1% O2. Gene expression profiles point to regulation of the cell cycle and metabolism as major altered gene clusters. Finally we discuss our counterintuitive observations in the context of the important role that hypoxia has in promoting neovascularization
Significant improvement of direct reprogramming efficacy of fibroblasts into progenitor endothelial cells by ETV2 and hypoxia
Sophisticated electrocatalysts for economical production of hydrogen Part A: Structural characterrization
An original procedure was applied in order to prepare composite electrocatalysts for hydrogen evolution reaction HER, containing Ni, Co and CoNi as a hyper d – electronic phase and TiO2 as a hypo-phase deposited on conductive carbon substrate Vulcan XC-72. The catalyst’s support (TiO2 and carbon) was thermally treated on 250 and 480°C in the atmosphere of H2 and N2. XRD and SEM methods were employed in order to elucidate the influence of temperature on the structural characteristics of catalysts
Carbon nanotubes as support for Co/TiO2 electrocatalysts for hydrogen evolution
The aim of this work was to apply multiwalled carbon nanotubes (MWCNTs) as a catalyst support in composite Co/TiO2/C electrocatalysts for hydrogen evolution. In order to elucidate the effect of MWCNTs, corresponding catalysts deposited on traditional carbon material Vulcan XC-72 were prepared as well
Bifurcations and chaos in the turbo decoding algorithm
Abstract. The turbo decoding algorithm is a high-dimensional dynamical system parameterized by a large number of parameters (for a practical realization the turbo decoding algorithm has more than 10 3 variables and is parameterized by more than 10 3 parameters). In this chapter we treat the turbo decoding algorithm as a dynamical system parameterized by a single parameter that closely approximates the signal-to-noise ratio (SNR). A whole range of phenomena known to occur in nonlinear systems, like the existence of multiple fixed points, oscillatory behavior, bifurcations, chaos and transient chaos are found in the turbo-decoding algorithm. We develop a simple technique to control transient chaos in turbo decoding algorithm and improve the performance of the standard turbo codes.
On the Asymptotic Convergence Properties of Turbo Codes
In this paper we present an analysis of the convergence properties of turbo codes at high signal-to-noise ratio (SNR). We introduce a simple nonlinear model based on the weight enumerator of the constituent codes to describe the iterates of the bit-error-rate (BER). Then, we characterize the dynamics of the decoder on the binary-input Gaussian channel in terms of fixed points along with the associated stability analysis. 1
La lithotritie par laser, un regard vers l'avenir? [Lithotripsy with a laser, a look toward the future?]
In the last few years the treatment of urinary calculi has been dramatically transformed by new endoscopic methods and extracorporeal shock wave lithotripsy. Laser lithotripsy is in keeping with this evolution. After a short description of the principle of laser lithotripsy, a prototype pulsed dye laser lithotriptor, developed by the Centre d'applications laser, Ecole polytechnique federale de Lausanne, is presented. This device is compared with other lasers proposed for the same application