453 research outputs found
Early electrophysiological markers of the sleep and motor control disorders during aging in rats with neurodegeneration of the cholinergic neurons
Cilj ove doktorske disertacije bio je da ispita uticaj starenja na spavanje u
eksperimentalnim modelima holinergičke neuropatologije Alchajmerove i
Parkinsonove bolesti, i da pronađe najranije znake poremećaja spavanja u
fiziološkom starenju i u starenju sa neurodegenerativnim bolestima.
Uticaj starenja na arhitekturu spavanja, elektroencefalografsku (EEG)
mikrostrukturu i motornu kontrolu, u toku svake faze spavanja, je praćen u
eksperimentalnim modelima bilateralnih oštećenja jedara nucleus basalis (NB) i
nucleus pedunculopontinus tegmentalis (PPT) u pacova, kao eksperimentalnim in
vivo modelima funkcionalno različitih holinergičkih neuropatologija.
Fiziološko starenje dovodi do topografski različitih promena arhitekture
spavanja i motorne kontrole iz senzomotorne kore (SMCx) u odnosu na
motornu koru (MCx). Pored promena arhitekture spavanja koje su se javile
samo u SMCx, fiziološko starenje dovodi i do povećanja propagacije delta i beta
oscilacija iz obe kore za vreme budnosti, ali samo iz MCx za vreme REM faze
spavanja.
Najraniji znaci starenja u eksperimentalnim modelima funkcionalno
različitih holinergičkih neuropatologija, dokazani po prvi put, predstavljaju
topografski specifične razlike u EEG mikrostrukturi za vreme REM faze
spavanja. Smanjenje delta EEG relativne amplitude u SMCx predstavlja najraniji
znak starenja kod NB lediranih pacova, dok povećanje sigma EEG relativne
amplitude u MCx predstavlja najraniji znak starenja kod PPT lediranih pacova,
za vreme REM faze spavanja. Pored toga, starenjem izazvane promene su
različito izražene kroz mišićnu kontrolu iz SMCx, a istovremeno i istovetno
izražene iz MCx u toku svih faza spavanja...The aim of the present doctoral dissertation was to evaluate the impact
of aging during sleep in the rat models of Alzheimer’s and Parkinson’s disease
cholinergic neuropathology, and to determine the possible different and earlier
onset of age-related sleep disorder during healthy aging and aging with the
neurodegenerative diseases.
We used the bilateral nucleus basalis (NB) and nucleus pedunculopontinus
tegmentalis (PPT) lesioned rats as the in vivo models of functionally distinct
cholinergic neuropathology, and we followed the impact of aging on sleep
architecture, the electroencephalographic (EEG) microstructure and motor
control across sleep/wake states.
We evidenced the topographically distinct impact of healthy aging on
sleep architecture and motor control within the sensorimotor (SMCx) vs. motor
cortex (MCx). Whereas healthy aging consistently altered only the SMCx sleep
architecture, it increased the delta and beta cortical drives from both cortices
during Wake, but only through the MCx drive during rapid eye movement
sleep (REM).
Our results have shown for the first time that the earliest signs of aging
during distinct cholinergic neuropathology were expressed through a different
and topographically specific EEG microstructure during REM. EEG delta
amplitude attenuation within the SMCx was the earliest sign of aging in the NB
lesion, whereas EEG sigma amplitude augmentation within the MCx was the
earliest sign of aging in the PPT lesion during REM. In addition, aging was
differently expressed through the SMCx drive alterations, but it was commonly
expressed through the MCx drive alterations during all sleep/wake states..
Antibacterial and antifungal activity of the liverwort (Ptilidium pulcherrimum) methanol extract
The antimicrobial activity of the methanol extract from the liverwort, Ptilidium pulcherrimum was evaluated against five bacterial and six fungal species. In vitro antibacterial activity was assessed by disc diffusion and microdilution methods. The extract showed a stronger effect against tested Gram (+) than Gram (-) bacteria. The antifungal activity of the methanol extract was tested using a microdilution method. The methanol extract showed strong antifungal activity. The best antifungal activity was achieved against Trichoderma viride compared to the synthetic fungicide bifonazol
INPUT SPLITS DESIGN TECHNIQUES FOR NETWORK INTRUSION DETECTION ON HADOOP CLUSTER
Intrusion detection system (IDS) is one of the most important components being used to monitor network for possible cyber-attacks. However, the amount of data that should be inspected imposes a great challenge to IDSs. With recent emerge of variousbig data technologies, there are ways for overcoming the problem of the increased amount of data. Nevertheless, some of this technologies inherit data distribution techniques that can be a problem when splitting a sensitive data such as network data frames across a cluster nodes. The goal of this paper is design and implementation of Hadoop based IDS. In this paper we propose different input split techniques suitable for network data distribution across cloud nodes and test the performances of their Apache Hadoop implementation. Four different data split techniques will be proposed and analysed. The techniques will be described in detail. The system will be evaluated on Apache Hadoop cluster with 17 slave nodes. We will show that processing speed can differ for more than 30% depending on chosen input split design strategy. Additionally, we’ll show that malicious level of network traffic can slow down the processing time, in our case, for nearly 20%. The scalability of the system will al so be discussed
Investigation on antibacterial synergism of Origanum vulgare and Thymus vulgaris essential oils
Essential oils are well known as strong antimicrobial agents of plant origin. In spite of this, the antimicrobial synergism of essential oils isolated from different plant species is poorly investigated. The following study examines the synergism of the essential oils of Origanum vulgare L. and Thymus vulgaris L against pathogenic bacteria, Staphylococcus aureus and Salmonella typhimurium. First, the antibacterial effect of the oils was tested, and the minimal inhibitory concentrations (MIC) of both oils were determined using the microdilution method. To test whether the oils act synergistically, every possible combination of essential oil concentrations was used in a dynamic checkerboard method. The results indicated that the oils indeed acted synergistically with fractional inhibitory concentration indexes of 0.45 and 0.50. [Projekat Ministarstva nauke Republike Srbije, br. 173032
Antibacterial and antifungal activity of the liverwort (Ptilidium pulcherrimum) methanol extract
The antimicrobial activity of the methanol extract from the liverwort, Ptilidium pulcherrimum was evaluated against five bacterial and six fungal species. In vitro antibacterial activity was assessed by disc diffusion and microdilution methods. The extract showed a stronger effect against tested Gram (+) than Gram (-) bacteria. The antifungal activity of the methanol extract was tested using a microdilution method. The methanol extract showed strong antifungal activity. The best antifungal activity was achieved against Trichoderma viride compared to the synthetic fungicide bifonazol.Antibakterijsko i antifungalno dejsto metanolnog ekstrakta jetrenjače Ptilidium pulcherrimum ispitivano je na 5 vrsta bakterija i 6 mikromiceta. Za ispitivanje in vitro antimikrobnog dejstva ekstrakta korišćena je metoda mikrodilucije na mikrotitracionim pločama i metoda difuzije sa filter diskova. Ekstrakt je pokazao jači efekat na testirane Gram (+), nego na Gram (-) bakterije. Antifungalna aktivnost metanolnog ekstrakta ispitana je mikrodilucionom metodom. Testirani ekstrakt pokazao je jak antifungalni potencijal na Trichoderma viride, Bifonazol je pokazao skoro identičnu fungistatičku aktivnost, dok je njegova fungicidna aktivnost bila nešto viša u poređenju sa metanolnim ekstraktom analizirane jetrenjače.Projekat ministarstva br. 143049 i 14304
Synthesis of BaFe12O19-BaTiO3 multiferroics by mechanical activation
A mixture of polycrystalline powders of Fe (70 % wt.) and BaTiO3 (30 % wt.) was ball-milled in a planetary mill under air atmosphere, for different time intervals: 60, 120, 180, 240, 300 and 360 min. During the mechanical activation, the powder was exposed to oxygen from the air, resulting in formation of iron oxides: FeO and then Fe2O3 and Fe3O4. XRD and SEM analyses of the activated powders revealed that the weight fraction of the iron oxides in the mixture and microcrystal size depend on the activation time. For the powders activated for different time intervals, average crystallite size (Dhkl), dislocation density (ρn) and average microcrystal size of BaTiO3 and Fe were determined. In order to investigate the influence of thermally induced structural changes on magnetic properties, the change of magnetic properties of the pressed activated powders during multiple heating in a magnetic field of 10KA/m was measured. Maximum magnetization of the samples was reached after heating at 620 K. Pressed powder samples were sintered at temperatures of 1100 oC and 1200 °C for 2h giving the different phase diagrams. The samples sintered at 1100 oC include BaTiO3, BaFe12O19 and BaFeO2,67 as the dominant components. The samples sintered at 1200 °C containing only two components, BaTiO3 and BaFe12O19, exhibited pronounced ferromagnetic and ferroelectric propertie
Radical scavenging and antimicrobial activity of essential oil and extracts of Echinophora sibthorpiana Guss. from Macedonia
This study was undertaken to determine the antioxidant and antimicrobial
effect of essential oil and extracts of Echinophora sibthorpiana Guss. (fam.
Apiaceae) collected in Macedonia. The chemical composition of E. sibthorpiana
essential oil was characterized by the presence of methyl eugenol (60.40%),
p-cymene (11.18%) and α-phellandrene (10.23%). The free radical scavenging
activity of extracts and essential oil was evaluated by DPPH and ABTS assays.
The aqueous extract of aerial parts exhibited the strongest scavenging
activity (IC50=1.67 mg/ml); results of the ABTS test showed that the most
effective was the ethanol extract of aerial parts (1.11 mg vit. C/g). The
essential oil showed stronger antioxidant activity compared to
hydroxyanisole, ascorbic acid and quercetin that were used in the DPPH and
ABTS tests, respectively. The total phenolic and flavonoid concentrations in
the extracts ranged between 38.65-60.72 mg GA/g, and 3.15-19.00 mg Qu/g,
respectively. The antimicrobial properties of the extracts and essential oil
were investigated using a micro-well dilution technique against human
pathogenic strains. The results were comparable with the effects of the
positive controls, streptomycin and fluconazole. These findings indicate that
E. sibthorpiana extracts and oil can be used in preventive treatments and as
an alternative for synthetic preservatives. [Projekat Ministarstva nauke
Republike Srbije, br. 173029 i br. 173021
The Phenotype Variability, of the Racka Sheep in the Republic of Serbia
ΔΕΝ ΔΙΑΤΙΘΕΤΑΙ ΠΕΡΙΛΗΨΗThe intensification of sheep production, by permanent genetic selection and the development of breeding technology, has led to the creation of highly productive sheep breeds. In this way, many highly productive breeds were created which could demonstrate their high production potentials only under perfect conditions of nutrition, accommodation and care. Preservation of indigenous breeds is of great importance in order to protect and safeguard those breeds and, in this way, it is possible to restore some of the characteristics that are lost during intensive selection, which are mostly related to resistance. The Racka sheep (Serbian: Vitoroga žuja) is considered to be an autochthonous breed and a genetic resource in the Republic of Serbia. As a primitive breed with low productivity, it offers no economic profitability and, thus, there is no great interest in its breeding. According to the FAO data from 2008-2014, the number of these sheep ranges from 500 to 1000. The objective of this study was to determine the phenotypic variability and to assess the external measurements of the Racka sheep. One-hundred fifty Racka breed ewes were included in this study. The effects of three farms on the phenotypic characteristics and their body indexes were calculated. The significance of the research is reflected in the advancement of this breed and in the assessment of the possibilities of selection work in these herds
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