Some details on the method for measuring activity changes of neuronal populations

Simple, complex action potentials (AP) and interspike recorded background activity (RBA) were detected and extracted from 12 rat cerebellar cortical recordings. For each recording, an averaged simple action potential (SAP) was formed. Fourier amplitude spectra of SAP and RBA were similar in all recordings. For one of the recordings, a series of RBA simulations (SBA) was generated, superimposing random SAPs, varying the superposition frequency (fsup). Average Fourier amplitude, Amp(SBA), was calculated, in order to use Amp(SBA)=f(fsup) as a calibration line for reading fsup of RBA, which is a measure of the population activity. A probability distribution for SAP intensities was derived and a family of calibration lines constructed. As all lines were linear and parallel (slope S) in log-log plots, a population activity change could be calculated as fsup2/fsup1=[Amp2(RBA)/Amp(RBA)]1/S.Jednostavni, složeni akcioni potencijali (AR) i međuspajkovna osnovna aktivnost (MOA) detektovani su i izdvojeni iz 12 registrovanih signala kore malog mozga pacova. Za svaku registraciju, formiran je usrednjeni jednostavni AR (JAR). Spektri Furijeovih amplituda JAR i MOA signala bili su slični kod svih registracija. Za jednu od registracija, superponiranjem slučajnih usrednjenih jednostavnih akcionih potencijala formiran je niz simulacija međuspajkovne osnovne aktivnosti (SOA), pri čemu je varirana frekvencija superpozicije (fsup). Izračunavana je srednja Furijeova amplituda, Amp(SBA), u cilju korišćenja Amp(SBA)=f(fsup) kao kalibracione linije za očitavanje fsup od MOA, što je mera za aktivnost populacije. Izvedena je raspodela verovatnoća za intenzitete JAR, pomoću koje je konstruisana familija kalibracionih linija. Kako su sve linije linearne i paralelne u log-log dijagramu, sa nagibom S, promena aktivnosti populacije može se izračunati kao fsup2/fsup1 =[Amp2(RBA)/Amp(RBA)]1/S.nul

Supplementary data for the article: Milenković, I.; Mitrović, A.; Algarra, M.; Lázaro-Martínez, J. M.; Rodríguez-Castellón, E.; Maksimović, V.; Spasić, S. Z.; Beškoski, V. P.; Radotić, K. Interaction of Carbohydrate Coated Cerium-Oxide Nanoparticles with Wheat and Pea: Stress Induction Potential and Effect on Development. Plants 2019, 8 (11). https://doi.org/10.3390/plants8110478

Supplementary material for: [https://doi.org/10.3390/plants8110478]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/3698

Age-related changes in the content of insulin: Like growth factor-l in rat brain

Although there has been extensive research on the effect of IGF-I on muscles and bone tissue, the effect on brain aging has received little attention. We investigated the IGF-I content in brains of differently aged rats. The IGF-I contents in cerebellar and cerebral cortex were found to be higher in immature rats (4-5 days old) compared to young adult (2.5 months old) and middle-aged (7.5-9 months old) rats. However, the decrease of mean IGF-I in middle-aged rats compared to immature animals was statistically significant only in the cerebellar codex. Our results indicate that IGF-I content decreases through the lifespan and maybe selectively in some brain regions.Vršena su istraživanja insulinu sličnog faktora rasta (IGF-I) na mišićno i koštano tkivo, ali je posvećena mala pažnja efektu na mozak u toku starenja. Mi smo ispitivali sadržaj IGF-I u moždanom tkivu pacova različite starosti. Nađeno je da su IGF-I koncentracije u kori malog mozga kao i velikog mozga mladih pacova (4-5 dana starih) više u poređenju sa sadržajima grupe tek-odraslih pacova starosti 2,5 meseca i grupe nešto starijih odraslih pacova (7,5-9 meseci starih). Međutim, smanjenje koncentracije IGF-I sadržaja samo u kori malog mozga nešto starijih pacova (7,5-9 meseci) bilo je značajno u odnosu na vrednosti u novorođenih (4-5 dana starih pacova). Naši rezultati ukazuju da IGF-I opada tokom života i moguće - selektivno u određenim moždanim regionima.nul

Age-related changes in the content of insulin: Like growth factor-l in rat brain

Although there has been extensive research on the effect of IGF-I on muscles and bone tissue, the effect on brain aging has received little attention. We investigated the IGF-I content in brains of differently aged rats. The IGF-I contents in cerebellar and cerebral cortex were found to be higher in immature rats (4-5 days old) compared to young adult (2.5 months old) and middle-aged (7.5-9 months old) rats. However, the decrease of mean IGF-I in middle-aged rats compared to immature animals was statistically significant only in the cerebellar codex. Our results indicate that IGF-I content decreases through the lifespan and maybe selectively in some brain regions.Vršena su istraživanja insulinu sličnog faktora rasta (IGF-I) na mišićno i koštano tkivo, ali je posvećena mala pažnja efektu na mozak u toku starenja. Mi smo ispitivali sadržaj IGF-I u moždanom tkivu pacova različite starosti. Nađeno je da su IGF-I koncentracije u kori malog mozga kao i velikog mozga mladih pacova (4-5 dana starih) više u poređenju sa sadržajima grupe tek-odraslih pacova starosti 2,5 meseca i grupe nešto starijih odraslih pacova (7,5-9 meseci starih). Međutim, smanjenje koncentracije IGF-I sadržaja samo u kori malog mozga nešto starijih pacova (7,5-9 meseci) bilo je značajno u odnosu na vrednosti u novorođenih (4-5 dana starih pacova). Naši rezultati ukazuju da IGF-I opada tokom života i moguće - selektivno u određenim moždanim regionima.nul

Application of Higuchi's fractal dimension from basic to clinical neurophysiology: A review.

BACKGROUND AND OBJECTIVE For more than 20 years, Higuchi's fractal dimension (HFD), as a nonlinear method, has occupied an important place in the analysis of biological signals. The use of HFD has evolved from EEG and single neuron activity analysis to the most recent application in automated assessments of different clinical conditions. Our objective is to provide an updated review of the HFD method applied in basic and clinical neurophysiological research. METHODS This article summarizes and critically reviews a broad literature and major findings concerning the applications of HFD for measuring the complexity of neuronal activity during different neurophysiological conditions. The source of information used in this review comes from the PubMed, Scopus, Google Scholar and IEEE Xplore Digital Library databases. RESULTS The review process substantiated the significance, advantages and shortcomings of HFD application within all key areas of basic and clinical neurophysiology. Therefore, the paper discusses HFD application alone, combined with other linear or nonlinear measures, or as a part of automated methods for analyzing neurophysiological signals. CONCLUSIONS The speed, accuracy and cost of applying the HFD method for research and medical diagnosis make it stand out from the widely used linear methods. However, only a combination of HFD with other nonlinear methods ensures reliable and accurate analysis of a wide range of neurophysiological signals

Ekumenik - Samarbete över skiljelinjen : En fallstudie kring funktionen av ekumenik och ekumeniska drivkrafter i tre västsvenska församlingar, tolkat ur ett religionssociologiskt perspektiv

Ekumenik är ett begrepp inom kristendomen vars syfte inbegriper ett försök att överbrygga samfunds olikheter och främja samarbete i gemensam tro. Ekumenik existerar i flera kristna sammanhang, exempelvis vid kyrkliga sammankomster och internationella samarbeten. Föreliggande studie ämnar undersöka ekumenik i lokal kontext, genom att klarlägga vilka ekumeniska samarbeten som pågår i tre olika samfund, och att ta reda på vilken funktion ekumenik har för samfunden och medlemmarnas engagemang.Studiens centrala del består av svar på semistrukturerade intervjufrågor som ställdes till tre olika samfunds kyrkoledning, en präst och två pastorer. Studien genomfördes på två orter, i två skilda kommuner. Fokus ligger på ekumenisk samverkan och en redogörelse av de funktioner som ekumenik anses fylla hos samfunden och deras medlemmar.Resultaten har tolkats ur ett religionssociologiskt perspektiv med teorier kopplade till funktionalism (funktionalism hänvisar här till religionens funktion för individen och gruppen).Studiens resultat visar att ekumenik kan fylla specifika funktioner hos kristna samfund och deras medlemmar. Den visar också att prioriteringen av ekumenik skiljer sig åt i de tre samfund som ingick i studien. I studien framkom att ekumenik bidrar till att skapa aktiviteter som anses meningsfulla för samfundens medlemmar, exempelvis föreläsningar, andrahandsaffärer och mötesplatser (strandkafé). Ekumenik kan på så vis stärka medlemmars deltagande och bidra till att mer tid ägnas åt ett samfunds verksamheter

Different Anesthesia in Rat Induces Distinct Inter-Structure Brain Dynamic Detected By Higuchi Fractal Dimension

The complexity, entropy and other non-linear measures of the electroencephalogram ( EEG), such as Higuchi fractal dimension (FD), have been recently proposed as the measures of anesthesia depth and sedation. We hypothesized that during unconciousness in rats induced by the general anesthetics with opposite mechanism of action, behaviorally and poligraphically controlled as appropriately achieved stable anesthesia, we can detect distinct inter-structure brain dynamic using mean FDs. We used the surrogate data test for nonlinearity in order to establish the existence of nonlinear dynamics, and to justify the use of FD as a nonlinear measure in the time series analysis. The surrogate data of predefined probability distribution and autocorrelation properties have been generated using the algorithm of statically transformed autoregressive process (STAP). FD then is applied to quantify EEG signal complexity at the cortical, hippocampal and pontine level during stable general anesthesia (ketamine/xylazine or nembutal anesthesia). Our study showed for the first time that global neuronal inhibition caused by different mechanisms of anesthetic action induced distinct brain inter- structure complexity gradient in Sprague Dawley rats. EEG signal complexities were higher at cortical and hippocampal level in ketamine/ xylazine vs. nembutal anesthesia, with the dominance of hippocampal complexity. In nembutal anesthesia the complexity dominance moved to pontine level, and ponto- hippocampocortical decreasing complexity gradient was established. This study has proved the Higuchi fractal dimension as a valuable tool for measuring the anesthesia induced inter- structure EEG complexity.Serbian Ministry of Science and Technological Development [173022]; NIH [AG16303

Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mT and 10 mT static magnetic fields on the complex bursting activity of the snail BR neuron

The components of complex bioelectrical activity - action potential (AP), interspike interval (ISI) and the quiet interburst interval (IBI), along with the effects of 2.7 mT and 10 mT static magnetic fields, were identified and examined in the spontaneously active Br neuron of the subesophageal ganglion complex of the garden snail Helix pomatia by fractal analysis using Higuchi's fractal dimension (FD). The normalized mean of the empirical FD distributions of bursting activity of the Br neuron were formed under different experimental conditions: before (Control), during (MF), and after exposure to the static magnetic field (AMF). Using the fractal analysis method for the first time, a separation of the AP, ISI and IBI components was successfully achieved. Our results show that fractal analysis with deconvolution of the normalized mean of the empirical FD distributions into Gaussian functions is a useful tool for revealing the effects of magnetic fields on the complexity of neuronal bioelectric activity and its AP, ISI and IBI components.Serbian Ministry of Education, Science and Technological Development {[}173027, 173045

Different Anesthesia in Rat Induces Distinct Inter-Structure Brain Dynamic Detected By Higuchi Fractal Dimension

The complexity, entropy and other non-linear measures of the electroencephalogram ( EEG), such as Higuchi fractal dimension (FD), have been recently proposed as the measures of anesthesia depth and sedation. We hypothesized that during unconciousness in rats induced by the general anesthetics with opposite mechanism of action, behaviorally and poligraphically controlled as appropriately achieved stable anesthesia, we can detect distinct inter-structure brain dynamic using mean FDs. We used the surrogate data test for nonlinearity in order to establish the existence of nonlinear dynamics, and to justify the use of FD as a nonlinear measure in the time series analysis. The surrogate data of predefined probability distribution and autocorrelation properties have been generated using the algorithm of statically transformed autoregressive process (STAP). FD then is applied to quantify EEG signal complexity at the cortical, hippocampal and pontine level during stable general anesthesia (ketamine/xylazine or nembutal anesthesia). Our study showed for the first time that global neuronal inhibition caused by different mechanisms of anesthetic action induced distinct brain inter- structure complexity gradient in Sprague Dawley rats. EEG signal complexities were higher at cortical and hippocampal level in ketamine/ xylazine vs. nembutal anesthesia, with the dominance of hippocampal complexity. In nembutal anesthesia the complexity dominance moved to pontine level, and ponto- hippocampocortical decreasing complexity gradient was established. This study has proved the Higuchi fractal dimension as a valuable tool for measuring the anesthesia induced inter- structure EEG complexity.Serbian Ministry of Science and Technological Development [173022]; NIH [AG16303