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101.
The aim of the study was to evaluate the effects of the Quiet eye (QE) phenomenon on performances during the shooting section of “Laser Run” of Modern Pentathlon, in two samples of athletes (novices and experts). The “Laser Run” consists of running and shooting activities. The study involved 18 experienced athletes of the Italian National Team of Modern Pentathlon (i.e., “elite” group) and 18 young and nonexpert athletes of a local Pentathlon club (i.e., “novice” group). Participants performed, in ecological conditions, five trials of four series of shootings (as it occurs in the real competitions), for a total of 20 series. During the shooting trials, athletes wore a mobile Eye Tracking System to record eye movements (saccades, blinks, and fixations). Key measures of the study were QE parameters (QE Duration [QED], Relative QED [RQED], and QE Onset), as well as the performance (accuracy and time to perform the event). The results revealed that both groups of athletes had a longer QED, RQED, and an earlier onset during their best shots than during the worse ones. Furthermore, differences between the groups showed that elite athletes had an earlier onset and a shorter QED than the novice group of athletes. These results provide insightful information about different cognitive and perceptual processes involved in Modern Pentathlon's athletes' performances at both the elite and non-elite level.  相似文献   
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Highlights? Minimizing the output of cerebellar GCs impairs GC-PC long-term plasticity ? Minimizing the output of cerebellar GCs affects PCs’ coding ? Minimizing the output of cerebellar GCs does not compromise motor performance ? Minimizing the output of cerebellar GCs partially disrupts motor memory formation  相似文献   
104.

Background

COPD exacerbations are associated with neutrophilic airway inflammation. Adhesion molecules on the surface of neutrophils may play a key role in their movement from blood to the airways. We analysed adhesion molecule expression on blood and sputum neutrophils from COPD subjects and non-obstructed smokers during experimental rhinovirus infections.

Methods

Blood and sputum were collected from 9 COPD subjects and 10 smoking and age-matched control subjects at baseline, and neutrophil expression of the adhesion molecules and activation markers measured using flow cytometry. The markers examined were CD62L and CD162 (mediating initial steps of neutrophil rolling and capture), CD11a and CD11b (required for firm neutrophil adhesion), CD31 and CD54 (involved in neutrophil transmigration through the endothelial monolayer) and CD63 and CD66b (neutrophil activation markers). Subjects were then experimentally infected with rhinovirus-16 and repeat samples collected for neutrophil analysis at post-infection time points.

Results

At baseline there were no differences in adhesion molecule expression between the COPD and non-COPD subjects. Expression of CD11a, CD31, CD62L and CD162 was reduced on sputum neutrophils compared to blood neutrophils. Following rhinovirus infection expression of CD11a expression on blood neutrophils was significantly reduced in both subject groups. CD11b, CD62L and CD162 expression was significantly reduced only in the COPD subjects. Blood neutrophil CD11b expression correlated inversely with inflammatory markers and symptom scores in COPD subjects.

Conclusion

Following rhinovirus infection neutrophils with higher surface expression of adhesion molecules are likely preferentially recruited to the lungs. CD11b may be a key molecule involved in neutrophil trafficking in COPD exacerbations.  相似文献   
105.
We tagged two juvenile short‐toed eagles in southern Italian peninsula with GPS satellite transmitters. According to previous visual observations, two different migratory routes for Italian short‐toed eagles to reach Africa in autumn have been proposed: via Sicily and via Gibraltar. These routes include different over‐water distances to cross the Mediterranean Sea, and thus different proportions of flight modes (soaring–gliding vs flapping–gliding) with resulting different transport costs. Considering different scenarios of energy cost of transport, with flapping–gliding flight over water being more costly than flying over land using soaring–gliding flight, we predicted a maximum optimal detour of 1218 km. Both individuals reached Africa using the longest, detoured, route, avoiding the longest water crossing. To achieve this they began migrating northwards, keeping for ca 700 km a direction opposite to that followed by any other migrating bird from the Northern hemisphere in autumn. The comparison of optimal detour predictions with observed migratory tracks suggests that this migratory strategy prioritizes not only energy minimization, but also safety, given the mortality risk associated with the sea crossing. Finally, it is unlike that these inexperienced individuals followed such a complex route relying only on endogenous information and we therefore suggest, also on the basis of field observations, that social interactions (adult guidance) allow these individuals to learn the detoured route.  相似文献   
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107.
Rhinovirus infections are the major cause of asthma exacerbations. We hypothesised that IL-15, a cytokine implicated in innate and acquired antiviral immunity, may be deficient in asthma and important in the pathogenesis of asthma exacerbations. We investigated regulation of IL-15 induction by rhinovirus in human macrophages in vitro, IL-15 levels in bronchoalveolar lavage (BAL) fluid and IL-15 induction by rhinovirus in BAL macrophages from asthmatic and control subjects, and related these to outcomes of infection in vivo. Rhinovirus induced IL-15 in macrophages was replication-, NF-κB- and α/β interferon-dependent. BAL macrophage IL-15 induction by rhinovirus was impaired in asthmatics and inversely related to lower respiratory symptom severity during experimental rhinovirus infection. IL-15 levels in BAL fluid were also decreased in asthmatics and inversely related with airway hyperresponsiveness and with virus load during in vivo rhinovirus infection. Deficient IL-15 production in asthma may be important in the pathogenesis of asthma exacerbations.  相似文献   
108.
A sanazole derivative, having a favorable single electron reduction potential (SERP) value compared to that of misonidazole, was synthesized and radiolabeled with [99mTcN(PNP)] precursor to evaluate its potential as a hypoxia imaging agent. The complex, which was lipophilic, could be prepared in good yields and challenging studies with cysteine showed stability of the complex against trans-chelation. However, despite being lipophilic as well as possessing favorable SERP value, biodistribution studies of this complex in fibrosarcoma tumor bearing Swiss mice showed low uptake in tumor. This observation is possibly attributed to fast clearance of the complex from blood, whereby the complex spends insufficient time in tumor to get reduced and trapped. Though uptake in tumor was low, slow clearance of activity from tumor suggests reduction and trapping of the complex in hypoxic cells. The present 99mTc-complex demonstrated acceptable values of tumor to blood (TBR) and tumor to muscle (TMR) ratios. However, low uptake in tumor which may not be indicative of the actual hypoxic status of the tumor, limit the utility of the complex to detect tumor hypoxia.  相似文献   
109.

Purpose

This paper assesses facility-specific life cycle greenhouse gas (GHG) emission intensities for electricity-generating facilities in the province of Ontario in 2008. It offers policy makers, researchers and other stakeholders of the Ontario electricity system with data regarding some of the environmental burdens from multiple generation technology currently deployed in the province.

Methods

Methods involved extraction of data and analysis from several publically accessible datasets, as well as from the LCA literature. GHG emissions data for operation of power plants came from the Government of Canada GHG registry and the Ontario Power Generation (OPG) Sustainable Development reports. Facility-specific generation data came from the Independent Electricity System Operator in Ontario and the OPG.

Results

Full life cycle GHG intensity (tonnes of CO2 equivalent per gigawatt hour) estimates are provided for 4 coal facilities, 27 natural gas facilities, 1 oil/natural gas facility, 3 nuclear facilities, 7 run-of-river hydro facilities and 37 reservoir hydro facilities, and 7 wind facilities. Average (output weighted) life cycle GHG intensities are calculated for each fuel type in Ontario, and the life cycle GHG intensity for the Ontario grid as a whole (in 2008) is estimated to be 201 t CO2e/GWh.

Conclusions

The results reflect only the global warming impact of electricity generation, and they are meant to inform a broader discussion which includes other environmental, social, cultural, institutional and economic factors. This full range of factors should be included in decisions regarding energy policy for the Province of Ontario, and in future work on the Ontario electricity system.  相似文献   
110.
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