Activity profile in elite Polish soccer players.

The aim of the present study was to determine and characterize the activity of male Polish Premier League soccer players during elite-level matches, depending on playing position, activity intensity range, and match period. The study sample comprised 1178 players. Amisco Pro® was used to track the match activity players. Statistical analysis of the total distance covered by players revealed that the greatest distance was covered by central midfielders (11894 ± 765 m) and external midfielders (11751 ± 686 m). In terms of velocity, the greatest distance was covered by players in the V1 range (0 ≤ V1 < 11 km · h-1, standing, walking), (7028 ± 294 m). The difference between the match periods was statistically non-significant, amounting to only 0.5%. As such they could prove useful for present and future comparisons between positions and represent the scientific basis for developing position-specific conditioning/training regimes for both clubs and individuals.

Reversible pressure pre-amorphization of a piezochromic metal-organic framework.

The piezochromic metal-organic framework Co2(Bdc)2Dabco·4DMF·H2O (Bdc denotes 1,4-benzenedicarboxylate, Dabco - 1,4-diazabicyclo[2.2.2]octane, and DMF - dimethylformamide) under ambient conditions is tetragonal (phase α) and at about 1.9 GPa undergoes a strong pressure-induced shortening of translational correlations in the sample. A broad gradual pre-amorphization process starting at about 0.7 GPa reduces the tetragonal symmetry and is described as phase ß. The pre-amorphization mechanism involves several competing distortions of the Bdc linkers and Co(ii)-coordination schemes. These in turn, affect the crystal field around the cations and their optical absorption. The compression strongly affects the VIS absorption of this piezochromic compound visibly changing its colour from blue to red.

Changes in the anaerobic threshold in an annual cycle of sport training of young soccer players.

The aim of the study was to assess changes in the anaerobic threshold of young soccer players in an annual training cycle. A group of highly trained 15-18 year old players of KKS Lech Poznan were tested. The tests included an annual training macrocycle, and its individual stages resulted from the time structure of the sports training. In order to assess the level of exercise capacities of the players, a field exercise test of increasing intensity was carried out on a soccer pitch. The test made it possible to determine the 4 millimolar lactate threshold (T LA 4 mmol · l(-1)) on the basis of the lactate concentration in blood [LA], to establish the threshold running speed and the threshold heart rate [HR]. The threshold running speed at the level of the 4 millimolar lactate threshold was established using the two-point form of the equation of a straight line. The obtained indicators of the threshold running speed allowed for precise establishment of effort intensity used in individual training in developing aerobic endurance. In order to test the significance of differences in mean values between four dates of tests, a non-parametric Friedman ANOVA test was used. The significance of differences between consecutive dates of tests was determined using a post-hoc Friedman ANOVA test. The tests showed significant differences in values of selected indicators determined at the anaerobic threshold in various stages of an annual training cycle of young soccer players. The most beneficial changes in terms of the threshold running speed were noted on the fourth date of tests, when the participants had the highest values of 4.01 m · s(-1) for older juniors, and 3.80 m · s(-1) for younger juniors. This may be indicative of effective application of an individualized programme of training loads and of good preparation of teams for competition in terms of players' aerobic endurance.

The influence of methisoprinol administered in ovo on the morphological structure of the spleen in turkeys.

This study analyzed the effect of a synthetic, low-toxic immunomodulator - methisoprinol - administered in ovo on the morphological structure of the spleen in turkeys. Experiments were conducted on three groups of 5-day-old BUT 9 turkeys (35 birds in each group) hatched from eggs which, on day 26 of incubation, had been administered methisoprinol (VetAgro, Lublin, Poland) in ovo in a dose of 5 mg (group I) or 20 mg per egg (group II). Poults hatched from eggs administered a physiological solution of NaCl in a dose of 0.1 ml per egg in ovo served as a control (group III). Samples of the spleen were collected from 5 birds selected at random from a group of decapitated 5-day-old poults and the prepared 7 fm-paraffin sections were stained with HE. A morphometric analysis of the germinal centres of the white pulp of the spleen was conducted by subjecting pictures taken with an optical microscope to a Digital Image Analysis using Axio Vision software (by Zeiss). The study demonstrated that in terms of the morphological structure, the spleen of the poults hatched from eggs administered 5 mg of methisoprinol (group I) did not differ considerably from the spleen of the control birds. In turn, spleens of the poults hatched from eggs administered 20 mg of methisoprinol per embryo were characterized by distinctively developed red pulp and within the area of the white pulp by distinct cortical section containing numerous lymphocytes. In spleens of the poults from this group, the morphometric examination also demonstrated a higher number of germinal centres of the white pulp as compared to their number in spleens of the birds from the other groups.

The influence of methisoprinol applied in ovo upon hatchability and health status of turkeys.

A study was undertaken to determine the effect of a synthetic immunomodulator, i.e. methisoprinol applied in ovo, upon the hatchability of turkey poults under conditions of a standard hatchery as well as on their health status evaluated based on analyses of selected biochemical indices in their blood serum. Experiments were conducted on 5 groups of BUT 9 turkeys at the age of 5 days (35 birds in each group) hatched from eggs to which methisoprinol (VetAgro, Lublin, Poland) was applied in ovo at a dose of 5 mg (group I), 10 mg (group II) or 20 mg per egg (group III) on the 26th day of incubation. Turkeys hatched from eggs to which a physiological solution of NaCl was applied on the same day at a dose of 0.1 ml per egg (group IV) as well as those hatched from eggs without in ovo injection (group V) served as controls. Five hundreds eggs were used in each group. Hatchability was evaluated based on the number of hatched poults in respect of the number of eggs with live embryos transferred from the setting compartment to the hatching compartment, that were subjected to in ovo administration of the preparations according to the experimental design. Blood serum of the 5-day-old turkey poults was analyzed for activities of AST, ALP, LDH-L, CK, lysozyme and ceruloplasmine as well as for total protein and albumin contents. Analyses were also conducted for the immune system organ index - percentage contribution of organs of the immune system (spleen, thymus and the bursa of Fabricius) in the body weight of turkeys. The study demonstrated that methisoprinol administered to turkey embryos in ovo on day 26 of incubation at doses of 5, 10 or 20 mg per embryo did not induce any disturbances in the hatching process or affect its final result. In addition, it was shown not to exert any negative effect on the health status of the reared turkey poults.

Sequential processing of the transmembrane chemokines CX3CL1 and CXCL16 by alpha- and gamma-secretases.

The chemokines CX3CL1/Fractalkine and CXCL16 are expressed as transmembrane molecules and can mediate cell-cell-adhesion. By proteolytic processing, CX3CL1 and CXCL16 are released from the cell surface by proteolytic shedding resulting in the generation of soluble chemoattractants. This ectodomain release is mediated by the alpha-secretase-like activity of the two disintegrins and metalloproteinases ADAM10 and ADAM17. Using CX3CL1 and CXCL16 constructs C-terminally fused to two Z-domains of Protein A (2Z-tag) we detect C-terminal fragments (CTFs) of both chemokines resulting from ADAM10-mediated cleavages at multiple sites as examined by inhibitor studies. Furthermore, inhibitor studies as well as genetic studies using presenilin 1/2-deficient cell lines suggest the involvement of gamma-secretase-but not beta-secretase-like activity in the processing of transmembrane chemokines. The combination of alpha- and gamma-secretase and proteasomal inhibitors points towards a sequential processing of transmembrane chemokines by first ADAM10 and then gamma-secretases and possible further degradation. This proteolytic processing cascade of transmembrane chemokines is similar to that described for Notch and E-cadherin where CTFs generated by gamma-secretase serve as intracellular signal transmitters.

Instrumental learning, but not performance, requires dopamine D1-receptor activation in the amygdala.

Substantial experimental evidence exists suggesting a critical role for dopamine in reinforcer-related processes, such as learning and drug addiction. Dopamine receptors, and in particular D1 receptors, are widely considered as modulators of synaptic plasticity. The amygdala contains both dopamine terminals and dopamine D1 receptors and is intimately involved in motivation and learning. However, little is known about the involvement of D1 receptor activation in two subnuclei of the mammalian amygdala, the central nucleus and basolateral complex in instrumental learning. Following recovery from surgery and preliminary training, rats with bilateral indwelling cannulae aimed at the central nucleus or basolateral complex were trained to lever-press for sucrose pellets over 12 sessions. Infusion of the selective D1 antagonist R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochloride (0.3 nmol and 3.0 nmol) prior to the first five training sessions dose-dependently impaired instrumental learning when compared with vehicle-infused controls. All rats were then exposed to five sessions drug-free; lever-pressing quickly reached equal levels across groups. A drug infusion prior to an 11th session revealed no effect on performance. Control experiments indicated that basic motivational processes and general motor responses were intact, such as spontaneous feeding and locomotor activity. These results show an essential role for D1-receptor activation in both the central nucleus and basolateral complex on the acquisition of lever pressing for sucrose pellets in rats, but not the performance of the behavior once conditioned. We propose that instrumental learning is dependent on plasticity in the central nucleus and basolateral complex amygdala, and that D1 receptor activation participates in transcriptional processes that underlie this plasticity.

Rhythms, synchrony and electrical coupling in the Locus coeruleus.

Electrical coupling of neurones is believed to promote synchronized activity. It may, however, also be a requirement for the maintenance of endogenous rhythmic activity in some systems. In en bloc isolated brainstem-spinal cord of the neonatal rat simultaneous whole cell recordings from pairs of LC neurones (n = 47 pairs) disclosed for the most part strongly synchronized activity which could take the form of tonic spiking or phasic bursts. Simultaneous whole cell recording from LC neurones and glia also revealed synchronized waves of depolarization in 7 of 17 pairs. This synchrony was partly due to respiratory-phased synaptic input and partly due to mechanisms, which were not dependent on chemical synapses. The gap junction uncoupler carbenoxolone suppressed non-synaptic rhythmic activity in LC neurones, but did not suppress either respiratory-phased synaptic input to these neurones or their excitatory response to increased CO(2). We give preliminary direct evidence for the existence of a current pathway between LC neurones, which is inhibited by carbenoxolone. Within the LC nucleus carbenoxolone-sensitive electrical coupling, which may involve neurone-glia as well as neurone-neurone interactions, may be required not just for synchronization, but also for the maintenance of rhythm.

[Influence of prion protein gene polymorphisms on performance traits in German meat sheep breeds]. / Einfluss der Prion Protein Gen Polymorphismen auf Leistungsmerkmale bei deutschen Fleischschafrassen.

PrP polymorphisms influence the scrapie susceptiblility of sheep. The objective of this study was to analyse the association between performance traits and the PrP genotype in the sheep breeds German black-headed and German white-headed mutton, Bleu du Maine, German mutton merino, Leine, Texel and Suffolk from Lower Saxony and Westphalia. We analysed performance traits such as scores for muscle mass, type and wool quality and the calculated daily weight gain using linear animal models. In all seven breeds no statistically significant associations were found between performance traits and the occurrence of ARR alleles, and the ARR/ARR genotypes, respectively. All genotyped sheep of all breeds investigated showed significantly superior performance traits in comparison to the non-genotyped animals.

Synchronized rhythms in chemosensitive neurons of the locus coeruleus in the absence of chemical synaptic transmission.

The activity of locus coeruleus (LC) neurons was examined in the en bloc isolated brainstem-spinal cord of the neonatal rat using paired whole cell or whole cell plus extracellular recording. In artificial cerebrospinal fluid (ACSF) LC neurons were synchronized by their respiratory innervation and in some neurons showing tonic or burst patterns of discharge these patterns of discharge could also be synchronized. Replacing ACSF with low Ca(2+)-high Mg(2+) generated synchronized rhythmic bursts which remained synchronized at high CO(2) (up to 20%). This rhythm was suppressed by TTX. Substitution of Ba(2+) for Ca(2+) in ACSF generated a synchronized rhythm which was TTX-insensitive. The frequency of this rhythm increased by 31+/-16% on raising CO(2) concentration from 2 to 10%. We conclude that the capacity of chemosensitive LC neurons to generate a synchronized rhythm depends on their electrical coupling, but not on chemical synaptic transmission.

Changing behavior within session: cyclicity and perseverance produced by varying the minimum ratio of a variable-ratio schedule.

Four pigeons repeatedly chose between a fixed-ratio (FR) 20 and a variable-ratio (VR) 40 schedule of reinforcement, in which the minimum ratio of the VR cycled within each session. The minimum ratio ascended and descended (ASCDESC), descended and ascended (DESCASC), or remained constant (unchanging). In Phase 1, 2 birds (Group 1) were exposed to ASCDESC series and 2 birds (Group 2) were exposed to the DESCASC series. Choice proportions changed with the cycling minimum ratio for Group 2 but not for Group 1. In Phase 2, Group 1 subjects were exposed to the DESCASC series and Group 2 subjects were exposed to the unchanging condition. Although Group 1's choice proportions appeared to be undifferentiated in Phase 2, Group 2's choice proportions continued to cycle for more than 100 sessions. Group 2 subjects were then moved to the ASCDESC series in the third phase, and choice proportions cycled with the minimum ratio as in the first phase. The descending portion of the series was the more powerful determinant of cyclicity. Response rates also changed with the minimum component ratio, a finding that goes against the claim of universality of a rise-and-fall within-session pattern of responding. That preference varied despite the constancy of the average ratio requirement suggests nonlinear averaging in quantitatively representing a variable schedule's value. The strong perseverance observed also lends support to a growing body of literature on history effects.

Technology transfer through performance management: the effects of graphical feedback and positive reinforcement on drug treatment counselors' behavior.

After drug treatment counselors at a community-based methadone treatment clinic were trained in implementing a contingency management (CM) intervention, baseline measures of performance revealed that, on average, counselors were meeting the performance criteria specified by the treatment protocol about 42% of the time. Counselors were exposed to graphical feedback and a drawing for cash prizes in an additive within-subjects design to assess the effectiveness of these interventions in improving protocol adherence. Counselor performance measures increased to 71% during the graphical feedback condition, and to 81% during the drawing. Each counselor's performance improved during the intervention conditions. Additional analyses suggested that counselors did not have skill deficits that hindered implementation. Rather, protocol implementation occurred more frequently when consequences were added, thereby increasing the overall proportion of criteria met. Generalizations, however, may be limited due to a small sample size and possible confounding of time and intervention effects. Nonetheless, present results show promise that feedback and positive reinforcement could be used to improve technology transfer of behavioral interventions into community clinic settings.

Ethanol consumption and the matching law: a choice analysis using a limited-access paradigm.

Choice analyses, especially R. J. Herrnstein's (1961, 1970) matching law, have recently been extended to substance abuse and drug research. The experiment reported here used a limited-access paradigm to engender ethanol consumption in Sprague-Dawley rats (Rattus norvegicus). After stable ethanol consumption was established, several 2-bottle choice tests were run. Relative volumes of solutions consumed were compared to relative ethanol concentrations as an application of the matching law. The formula for the generalized matching law confirmed that although biases varied, they were small, and more important, sensitivities to the relative concentrations were positive in 24 of 28 subjects. The results also revealed a high positive correlation between baseline ethanol consumption (g/kg) and subsequently assessed sensitivity. Overall, these findings suggest that a matching law analysis can be useful for examining ethanol intake in randomly bred rats.

Locus coeruleus neurones in vitro: pH-sensitive oscillations of membrane potential in an electrically coupled network.

The response to hypercapnic acidosis (2-8% CO2, bath pH 7.8-7.2) was examined in whole cell recordings from neonatal (P1 to P5) rat Locus coeruleus (LC) neurones in the in vitro brainstem-spinal cord preparation exposed to low Ca2+ (0.2 mM)-high Mg2+ (5 mM). This medium suppressed chemical synaptic transmission and resulted in a pattern of subthreshold oscillations of membrane potential and rhythmic burst discharge which was synchronized throughout the network. The oscillation was suppressed, and the discharge of individual neurones desynchronized, by the gap junction uncoupler, carbenoxolone, indicating that in low Ca2+-high Mg2+ LC neurones form an electrically coupled network. Switching from 2 to 8% CO2 decreased the oscillation amplitude and increased its frequency. The oscillation was suppressed by external Cd2+ and by TTX. but persisted during injection into the cell soma of QX-314. We conclude that in LC neurones acidosis increases the frequency of a Ca2+- and Na+-dependent dendritic oscillator which is synchronized by gap junction coupling throughout the network. This coupling is retained during acidosis.