15 research outputs found
On entropy of probability integral transformed time series
Abstract
The goal of this paper is to investigate the changes of entropy estimates when the amplitude distribution of the time series is equalized using the probability integral transformation. The data we analyzed were with known properties—pseudo-random signals with known distributions, mutually coupled using statistical or deterministic methods that include generators of statistically dependent distributions, linear and non-linear transforms, and deterministic chaos. The signal pairs were coupled using a correlation coefficient ranging from zero to one. The dependence of the signal samples is achieved by moving average filter and non-linear equations. The applied coupling methods are checked using statistical tests for correlation. The changes in signal regularity are checked by a multifractal spectrum. The probability integral transformation is then applied to cardiovascular time series—systolic blood pressure and pulse interval—acquired from the laboratory animals and represented the results of entropy estimations. We derived an expression for the reference value of entropy in the probability integral transformed signals. We also experimentally evaluated the reliability of entropy estimates concerning the matching probabilities
QUANTITY AND QUALITY OF BUTTON MUSHROOMS (AGARICUS BISPORUS) WITH RESPECT TO THE USAGE OF TWO DIFFERENT TYPES OF MYCELIUM
Gljive Agaricus bisporus popularno nazvane šampinjoni najzastupljenije su gljive u pogledu proizvodnje na svjetskoj razini. Izgled gljiva dijelom ovisi o tehnologiji, ali prvenstveno i o karakteristikama micelija koji se upotrebljava za inokulaciju prilikom proizvodnje supstrata za proizvodnju šampinjona. U radu su analizirani rezultati dobiveni berbom gljiva tijekom tri vegetacijska ciklusa. Supstrati su bili inokulirani s dva različita tipa micelija U1 i 608. Tijekom istraživanja pratila su se dva parametra s obzirom na upotrebu različitih tipova micelija.; količina i krupnoća gljiva. Rezultati provedenoga istraživanja pokazuju da postoji određena razlika po pitanju prinosa i krupnoće ubranih gljiva, ali ne statistički značajna.Mashrooms Agaricus bisporus, popularly called button mushrooms, are most widespread mushrooms with respect to the production worldwide. The appearance partly depends on the technology, but primarily on the characteristics of the mycelium used for inoculation in preparing the substrate for mushroom production. The paper analyses results obtained from mushrooms gathered in three vegetation cycles. The substrates were inoculated with two different types of mycelium, U1 and 608. In the research two parameters were followed with respect to the usage of different types of mycelium, quantity and quality of mushrooms. The results of the research show that there is a definite difference in yield and size of gathered mushrooms but it is not statistically significant
Overexpression of oxytocin receptors in the hypothalamic PVN increases baroreceptor reflex sensitivity and buffers BP variability in conscious rats
BACKGROUND AND PURPOSE: The paraventricular nucleus (PVN) of the hypothalamus is an important integrative site for neuroendocrine control of the circulation. We investigated the role of oxytocin receptors (OT receptors) in PVN in cardiovascular homeostasis. EXPERIMENTAL APPROACH: Experiments were performed in conscious male Wistar rats equipped with a radiotelemetric device. The PVN was unilaterally co-transfected with an adenoviral vector (Ad), engineered to overexpress OT receptors, and an enhanced green fluorescent protein (eGFP) tag. Control groups: PVN was transfected with an Ad expressing eGFP alone or untransfected, sham rats (Wt). Recordings were obtained without and with selective blockade of OT receptors (OTX), during both baseline and stressful conditions. Baroreceptor reflex sensitivity (BRS) and cardiovascular short-term variability were evaluated using the sequence method and spectral methodology respectively. KEY RESULTS: Under baseline conditions, rats overexpressing OT receptors (OTR) exhibited enhanced BRS and reduced BP variability compared to control groups. Exposure to stress increased BP, BP variability and HR in all rats. In control groups, but not in OTR rats, BRS decreased during stress. Pretreatment of OTR rats with OTX reduced BRS and enhanced BP and HR variability under baseline and stressful conditions. Pretreatment of Wt rats with OTX, reduced BRS and increased BP variability under baseline and stressful conditions, but only increased HR variability during stress. CONCLUSIONS AND IMPLICATIONS: OT receptors in PVN are involved in tonic neural control of BRS and cardiovascular short-term variability. The failure of this mechanism could critically contribute to the loss of autonomic control in cardiovascular disease
Clustering as a Support Technique in Phenotyping and Genotyping
Bajić, D., Mišić, N.Ž., Ostojić, M., Japundžić-Žigon, N. (2021) Clustering as a Support Technique in Phenotyping and Genotyping. Biologia Serbica 43(1): 68. ISSN 2334-6590 Department of Biology and Ecology, Faculty of Sciences, University of Novi Sad, Serbia Belgrade BioInformatics Conference 2021, 21-25 June 2021, Vinča, Serbia
Approximate solutions of time and time-space fractional wave equations with variable coefficients
Vasopressin, Central Autonomic Control and Blood Pressure Regulation
Purpose of Review: We present recent advances in understanding of the role of vasopressin as a neurotransmitter in autonomic nervous system control of the circulation, emphasizing hypothalamic mechanisms in the paraventricular nucleus (PVN) involved in controlling sympathetic outflow toward the cardiovascular system. Recent Findings: Suggest that somato-dendritically released vasopressin modulates the activity of magnocellular neurons in the PVN and SON, their discharge pattern and systemic release. Advances have been made in uncovering autocrine and paracrine mechanisms controlling presympathetic neuron activity, involving intranuclear receptors, co-released neuroactive substances and glia. Summary: It is now obvious that intranuclear release of vasopressin and the co-release of neuroactive substances in the PVN, as well as the level of expression of vasopressin receptors, modulate sympathetic outflow to the cardiovascular system and determine vulnerability to stress. Further research involving patho-physiological models is needed to validate these targets and foster the development of more efficient treatment.</p