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Physical inactivity is a major contributor to low-grade systemic inflammation. Most of the studies characterizing interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) release from exercising legs have been done in young, healthy men, but studies on inactivity in older people are lacking. The impact of 14 days of one-leg immobilization (IM) on IL-6 and TNF-α release during exercise in comparison to the contralateral control (CON) leg was investigated. Fifteen healthy men (age 68.1?±?1.1?year (mean?±?SEM); BMI 27.0?±?0.4 kg·m2; VO2max 33.3?±?1.6 ml·kg?1·min?1) performed 45?min of two-leg dynamic knee extensor exercise at 19.5?±?0.9 W. Arterial and femoral venous blood samples from the CON and the IM legs were collected every 15?min during exercise, and thigh blood flow was measured with ultrasound Doppler. Arterial plasma IL-6 concentration increased with exercise (rest vs. 45?min, main effect p?p?p?=?.085, effect size 0.28) higher in the IM leg compared to the CON leg (288 (95% CI: 213–373) vs. 220 (95% CI: 152–299) pg·min?1, respectively). There was no release of TNF-α in either leg and arterial concentrations remained unchanged during exercise (p?>?.05). In conclusion, exercise induces more pronounced IL-6 secretion in healthy older men. Two weeks of unilateral immobilization on the other hand had only a minor influence on IL-6 release. Neither immobilization nor exercise had an effect on TNF-α release across the working legs in older men.  相似文献   
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In Experiment 1, two groups of pigeons were autoshaped to a green keylight CS and then administered either CS only or truly random control (TRC) response-elimination procedures with the green keylight CS. The groups ceased responding at comparable rates. In a subsequent reacquisition test with a vertical-line key stimulus, the group administered CS only during response elimination reacquired the keypecking CR more rapidly. The two groups were then administered the alternative response-elimination treatment with the vertical-line CS. Again, the groups ceased responding at comparable rates. In a subsequent reacquisition test with a red keylight CS, the group administered CS only during the immediately preceding response-elimination phase reacquired the keypecking CR more rapidly. In Experiment 2, following initial acquisition, the CS-only and TRC response-elimination treatments were administered under the context-change and no-context change conditions. The TRC/context-change and CS-only/context-change groups ceased responding more rapidly than either the TRC/ no-context-change or CS-only/no-context-change groups. In subsequent reacquisition to a novel CS, the CS-only/no-context-change group reacquired the fastest, the TRC/no-context-change group reacquired the slowest, and the CS-only/context-change and TRC/context-change groups reacquired at similar intermediate rates. Implications of these results for the context-blocking hypothesis are discussed.  相似文献   
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IntroductionEffective implementation and continual compliance with ISO 15189:2012 require ongoing commitment and active involvement of laboratory staff. Our aim was to assess attitudes regarding accreditation implementation by conducting a survey in three Croatian accredited medical laboratories.Materials and methodsAn anonymous survey consisting of 34 questions was distributed either electronically or in a paper form a week prior to scheduled annual audits. Distributions of answers regarding age, work experience, laboratory workplace, and education level and according to the respective laboratory were compared.ResultsThe overall response rate was 76% (225/297). Preference towards working in an accredited laboratory and a positive attitude were revealed by 70% and 56% participants, respectively, with better process documentation as the main advantage. Only 14% of responders considered themselves completely familiar with ISO 15189:2012. Total of 68% of responders felt that accreditation increases the usual workload, with excessive paperwork as the main contributor. Half of the responders declared partial agreement that accreditation requirements and expectations were clearly explained and claimed that their suggestions were taken into account only occasionally, which was especially emphasized by technical staff. The vast majority (89%) completely follow the prescribed protocols. Only 27% consider turnaround time monitoring useful. Competence assessment is considered efficient by 41% of responders. The majority (73%) prefer an online audit in times of COVID-19.ConclusionsDespite an overall positive attitude towards accreditation, further efforts are needed in providing better education about ISO 15189:2012 for technical staff and modifying formats of competence assessment, in order to achieve better adherence to ISO 15189:2012 requirements.  相似文献   
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The notion that ‘customer satisfaction’ should be the ultimate measure of quality provision of any service organization is often accepted in the higher education context. However, measuring the quality of an educational institution based on students’ satisfaction is insufficient as it diverts the focus from student development, advancement and growth to an affective evaluation of the service. More appropriate measures of quality of higher education institutions are student engagement and learning. This study describes the likely impact of perceived overall quality of higher education institutions on student engagement. The contribution of this study is twofold. First, it draws attention to the importance of higher education institution quality as the main institutional-level determinant of student engagement and, second, it suggests a comprehensive multilevel conceptual framework for its empirical testing.  相似文献   
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Research on successful aging has shown that physical training can have positive effects on cognitive and motor functions in the elderly. The article describes a study involving a 12-week multidimensional exercise program (endurance, strength, flexibility and relaxation) with one session per week which was established for older adults (60 years onwards). Cognitive training (e. g. attention, concentration and memory) was additionally targeted in each exercise session. The exercise program was evaluated by different standardized tests regarding its effects on motor and cognitive performance as dependent variables. In a randomized controlled trial with experimental and waiting control group two points of measurement were conducted. The results showed a significant increase in fitness parameters (endurance, strength and dynamic balance) for the experimental group in contrast to the control group. The expected significant increase for cognitive functions was not found. There is still not enough known about the relationship between cognitive function and physical activity in older adults.  相似文献   
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The decision to follow the demonstrative this with a noun phrase is important to students’ writing development. Previous research has emphasized when students should not attend this rather than studying why students make the choice. Using a corpus-linguistic approach, we investigated 1,999 instances of (un)attended this in student technical and academic writing. High shares of unattended this were found in both text types as well as in original and revised drafts.  相似文献   
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Social media applications are extending the information and communication technology landscape in the public sector and are used to increase government transparency, participation and collaboration in the U.S. federal government. The success, impact and performance of these new forms of bi-directional and networked interactions can provide insights to understand compliance with the mandate of the Open Government Initiative. Many government agencies are experimenting with the use of social media, however very few actively measure the impact of their digital interactions. This article builds on insights from social media directors in the U.S. federal government highlighting their current lack of measurement practices for social media interactions. Based on their articulated needs for measurement, existing rules regulating the extent of measurement practices and technological features of the main social media platforms, a framework is presented that traces online interactions to mission support and the resulting social media tactics. Implications for both researchers and practitioners are discussed.  相似文献   
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