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Trimassnaja vibracionnaja mel'nica s chetyr'mja vibrovozbuditeljami

100%
Solonaya E., Liubin V.
Motrol. Motoryzacja i Energetyka Rolnictwa
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2013
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tom 15
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nr 4
2

Does brain ability to synchronize with 40 Hz auditory stimulation change with age?

86%
Griskova-Bulanova I., Dapsys K., Maciulis V.
Acta Neurobiologiae Experimentalis
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2013
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tom 73
|
nr 4
Auditory steady-state responses (ASSRs) are widely applied to test brain ability to follow external stimulation and this appeared to be a promising method in neuropsychiatry disorders. Nevertheless, there is no established conclusion on the way aging affects phase-locking measures of ASSRs in healthy subjects. We aimed to identify the effects of aging on phase- locking measures of 40 Hz ASSR. The effect of aging was tested in a sample of 46 healthy male subjects (20-58 years old) during eyes open condition. Stimuli were 500 ms trains, consisting of 20 identical clicks (1.5 ms burst of white noise) delivered binaurally. Time-frequency analysis of the data was performed and phase-locking index, evoked amplitude and total intensity measures were extracted and decomposed by non-negative multi-way factorization. As shown by curve-fitting analyses, phase-locking index and evoked amplitudes were diminishing with age in the linear manner. This was also proven by ANOVA testing when sample was divided into age groups. No effect of age on the total intensity was found. The complexity of the factors modulating the 40 Hz ASSR is not entirely solved; nevertheless, the current results suggest that the ability to synchronize to high frequency external stimulation diminishes with age. This should be taken into account, particularly when ASSRs are used in clinical practice, comparing patients and healthy subjects.
3

Synchronisation of the autumn mass migration of passerines: a case of Robins Erithacus rubecula

72%
Nowakowski J. K., Remisiewicz M., Keller M., Busse P., Rowinski P.
Acta Ornithologica
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2005
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tom 40
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nr 2
103-115
The pattern of autumn migration of the Robin was studied through an analysis of daily dynamics for the birds caught in the years 1984-1997 at four ringing stations (two on the Baltic coast and two in inland Poland). In a given year, migration dynamics was found to be distinctly similar at all stations. It showed conspicuous consistence (± 2 days) in the dates with peak numbers. This could be explained by assuming that Robins take off at the same time across a large breeding ground, and arrive almost simultaneously at stopover sites located over extensive areas. Moreover, migration dynamics from year to year at a given station was also remarkably similar, though this phenomenon was more distinct at the inland stations than at the coastal ones. Day-to-day fluctuations in numbers were on an average the highest at the coastal station most exposed to variable weather, the lowest at the inland stations, and intermediate at the more "sheltered" of the coastal station. The paper discusses the extent to which such results can reflect the influence of weather conditions on passage, or else a precise internal (physiological and genetic) mechanism responsible for the timing of migration.
4

Effects of different intravaginal progesterone releasing devices on estrous synchronization and LH surge in fat-tailed ewes during non-breeding season

72%
Gungor O., Cenesiz M., Pancarci S. M., Yildiz S., Kaya M., Kacar C., Ozyurtlu N., Gurbulak K.
Medycyna Weterynaryjna
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2007
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tom 63
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nr 11
1316-1319
The aims of this study were to compare two methods of estrus synchronization and to evaluate the effectiveness of the PMSG treatment combined with P4 application. Fifty non-lactating seasonal anestrus fat-tailed ewes were randomly assigned into five groups. The controlled internal drug release devices (CIDR) were applied during day 14 in group I and in group II. Progesterone impregnated sponges were applied during day 14 in group III and in group IV. And then 500 IU PMSG was injected in group I and III i.m. intravaginal devices removed. Ewes in group V served as controls. There was no difference between the groups in the peak value of LH and LH surge. Although LH surge was seen in the control groups 5 sheep, none of the control ewes expressed estrus. Different progestagen treatments have no different results when they are evaluated in terms of the success of the estrus synchronization. PMSG application, after P4 treatment, increased the success of the synchronization.
5

New strategies to improve the efficiency of the ovsynch protocol in primiparous dairy cows

72%
Cirit U., Ak K., Ileri I. K.
Bulletin of the Veterinary Institute in Puławy
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2007
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tom 51
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nr 1
The aim of this study was to create new strategies to increase the pregnancy rate, in "ovsynch protocol" treatment. Two programs for synchronisation of ovulation and for synchronisation of ovulation and oestrus, similar to the ovsynch, were developed for the use in lactating primiparous dairy cows. Lactating Holstein-Friesian cows were randomly divided into five treatment groups: the GPG group (ovsynch) was treated with GnRH on day 0, PGF (PGF2α) on day 7, and received the second dose of GnRH 48 h later; the groups -7PGPG and - 2PGPG received the same treatment as the GPG group, but were given an additional injection of PGF 7 and 2 d before the start of the GPG treatment; respectively, the PG9PG group received the same treatment as the -2PGPG group, with the modification that the first GnRH injection was given simultaneously with the first PGF on the 2nd d; the GPEG group received the same treatment as the GPG group, but was injected an additional oestradiol propionate (EP) 24 h after the PGF. Plasma progesterone concentrations were determined at the days of the first hormone injection and the last PGF injection. Ovulation rates after the first GnRH and last PGF injections were calculated and presumptive sizes of the follicles on the last PGF injection day were determined in all the cows by rectal palpation. Cows detected to be at oestrus in 72 h after the last PGF injection was inseminated between the 8th and 12th h of their oestrus. Cows not detected to be in oestrus by 72 h after the last PGF received timed artificial insemination (TAI). While the ovulations mostly occurred in the GPG, GPEG, and -7PGPG groups at a period between the 48th and 96th h after the last PGF injection, the ovulations had shifted and occurred between 72 and 120 h, with 66.7% of all ovulations recorded between 72 and 96 h in the -2PGPG group. In the PG9PG group, ovulations took place dispersedly between the 0th and 120th h after the last PGF injection. The pre-synchronisation treatment (-7PGPG) by a PGF injection 7 d prior to the ovsynch protocol did not enhance the ovulation or pregnancy rates. The pre-synchronisation treatment by PGF injected 2 d before the ovsynch protocol, increased the number of cows that ovulated after the first GnRH injection (88.9% vs. 38.9%; P<0.05), produced smaller follicles at the time of the second PGF injection (1.1±0.13 vs. 1.6±0.16 cm; P<0.05) and increased pregnancy rates numerically (72.2% vs. 50.0%; P>0.05). Adding EP to GPG (GPEG), enhanced the expression of oestrus (P<0.05) and increased pregnancy rates slightly (60.0% vs. 50.0%; P>0.05). In conclusion, the -2PGPG and GPEG treatments are potentially new methods for routine synchronisation of ovulation and oestrus and/or ovulation, respectively, in primiparous Holstein-Friesian cows.
6

Reduced degree of long-range phase synchrony in pathological human brain

72%
Bhattacharya J.
Acta Neurobiologiae Experimentalis
|
2001
|
tom 61
|
nr 4
7

Cell cycle synchronization in the root meristem of Allium cepa L.

72%
Woloszyn M., Golczyk H., Joachimiak A.
Acta Biologica Cracoviensia. Series Botanica
|
2001
|
tom 43
A high level of cell cycle synchronization in Allium cepa was achieved using a 24 h hydroxyurea block (1.25 mM) followed by 20 h of recovery (without hydroxyurea) and a subsequent 4 h treatment with saturated α-bromonaphthalene solution. This procedure was very effective in producing a synchronously dividing cell population with a 76% mean mitotic index and a 30% frequency of metaphase stages. After release from hydroxyurea arrest, large fractions of cells synchronously entered successive phases: G1, S, and G2. The calculated duration of the cell cycle, 13 h, is in general accordance with previous reports. A detailed protocol for obtaining a high mitotic index and a large portion of cells in a particular cycle phase (G1, S, G2) was prepared.
8

Synchronization of oestrus in Hamdani ewes: the use of different PMSG doses

72%
Timurkan H., Yildiz H.
Bulletin of the Veterinary Institute in Puławy
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2005
|
tom 49
|
nr 3
9

The effect of carbachol on the phase of free-running locomotor activity rhythm under constant darkness [DD] and constant light [LL] in mice

72%
Gaweda M.
Folia Biologica
|
1998
|
tom 46
|
nr 3-4
10

In vitro development of porcine nuclear-transferred embryos derived from fibroblast cells analysed cytometrically for apoptosis incidence and accuracy of cell cycle synchronization at the G0/G1 stages

58%
Samiec M., Skrzyszowska M., Bochenek M.
Annals of Animal Science
|
2013
|
tom 13
|
nr 4
11

Cortical synchronization suggests neural principles of visual feature grouping

58%
Eckhorn R.
Acta Neurobiologiae Experimentalis
|
2000
|
tom 60
|
nr 2
Compositions of visual scenes are related here to neural signals in visual cortex and to cortical circuit models to understand neural mechanisms of perceptual feature grouping. Starting from the hypothesis that synchronization and decoupling of cortical y-activities (35-90 Hz) define the relations among visual objects, we concentrate on synchronization related to (1) static retinal stimulation during ocular fixation, and (2) transient stimulation by sudden shifts in object position. The synchronization hypothesis has been tested by analyzing signal correlations in visual cortex of monkeys with the following results: Static retinal stimuli induce loosely phase-coupled y-activities among neurons of an object's cortical representation. Patches of y-synchronization become decoupled across the representation of an object's contour, and therby can code figure-ground segregation. Transient stimuli evoke synchronized volleys of stimulus-locked activities that are typically non-rhythmic and include low frequency components in addition to those in the y-range. It is argued that stimulus-induced and stimulus-locked synchronizations may play different roles in perceptual feature grouping.
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