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1.
The purpose of this study was to analyse the raw lifting speed collected during four different resistance training exercises to assess the optimal sampling frequency. Eight physically active participants performed sets of Squat Jumps, Countermovement Jumps, Squats and Bench Presses at a maximal lifting speed. A linear encoder was used to measure the instantaneous speed at a 200 Hz sampling rate. Subsequently, the power spectrum of the signal was computed by evaluating its Discrete Fourier Transform. The sampling frequency needed to reconstruct the signals with an error of less than 0.1% was f99.9 = 11.615 ± 2.680 Hz for the exercise exhibiting the largest bandwidth, with the absolute highest individual value being 17.467 Hz. There was no difference between sets in any of the exercises. Using the closest integer sampling frequency value (25 Hz) yielded a reconstruction of the signal up to 99.975 ± 0.025% of its total in the worst case. In conclusion, a sampling rate of 25 Hz or above is more than adequate to record raw speed data and compute power during resistance training exercises, even under the most extreme circumstances during explosive exercises. Higher sampling frequencies provide no increase in the recording precision and may instead have adverse effects on the overall data quality.  相似文献   
2.

Introduction

Screening programs for colorectal cancer (CRC) are mainly based on a first-line fecal immunochemical test for hemoglobin (FIT). Fecal M2-type pyruvate kinase (M2-PK) has been evaluated in clinical settings showing promising results for early CRC detection. However, the impact of fecal M2-PK assessment on the performance of first-round CRC screening programs is not known. We investigated whether fecal M2-PK alone or in combination with FIT may improve CRC screening efficacy in the general population.

Materials and methods

A total of 1027 asymptomatic subjects (median age 66 [59-74] years; females 504 [49.1%]), identified through the general practitioners’ rosters, were invited for the collection of 2 fecal samples for FIT and M2-PK evaluation. Participants with at least positive one fecal test were referred for colonoscopy. Quality indicators for screening performance were calculated and analyzed using Fisher’s exact test.

Results

Overall, 572 subjects underwent both FIT and M2-PK assessment (participation rate 55.7%): 93 participants showed positive results for at least one test (positivity rate 16.3%). Only 10 patients were positive for both tests. Attendance rate to colonoscopy was 86.0% and a total of 65 adenomas and 7 cancers were detected. Combined use of FIT and fecal M2-PK permitted the identification of 18 more neoplasm (25%) without improving colonoscopy workload, as deduced by the comparable number needed to scope (P = 0.402).

Conclusion

The addition of M2-PK testing to FIT offers the potential to detect additional neoplasms that either do not bleed or only bleed intermittently without reducing participation rate and without increasing endoscopy workload.Key words: biomarker, colorectal cancer, occult blood, M2-type pyruvate kinase, screening  相似文献   
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Our model analyzes the effects of the interplay between environmental degradation and consumption choices on economic growth dynamics and on economic agents’ welfare. We show that if private goods can be consumed as substitutes for environmental goods, then economic growth may be fueled by environmental deterioration. In this context, undesirable economic growth may occur, characterized by an inverse correlation between aggregate capital accumulation and economic agents’ welfare.  相似文献   
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This paper proposes a price index for artists adjusted for the quality of the paintings, based on the ratio between the average market price and the average pre-sale estimate for paintings. We apply this methodology to a group of selected artists and schools presented in auctions worldwide in the period 1990–2001. A comparison with quality unadjusted and hedonic indices is also conducted.JEL Classification: C10, Z11  相似文献   
7.
For the transient response analysis of a flexible slider-crank mechanism, the coordinate partitioning scheme and the Udwadia-Kalaba formulation are herein compared. The flexibility of the coupler has been modelled by means of a single Timoshenko beam element. The present analytical treatment can be viewed as an extension of the model discussed by Shabana in his textbook.  相似文献   
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The development of human body perception has long been investigated, but little is known about its early origins. This study focused on how a body part highly relevant to the human species, namely the hand, is perceived a few days after birth. Using a preferential‐looking paradigm, 24‐ to 48‐hr‐old newborns watched biomechanically possible and impossible dynamic hand gestures (Experiment 1, N = 15) and static hand postures (Experiment 2, N = 15). In Experiment 1, newborns looked longer at the impossible, compared to the possible, hand movement, whereas in Experiment 2 no visual preference emerged. These findings suggest that early in life the representation of the human body may be shaped by sensory‐motor experience.  相似文献   
10.
Processes of designing for systemic innovation for sustainable development (SD) through the lens of three long-term case studies are reported. All case studies, which originated from the SLIM (Social Learning for the Integrated Management and Sustainable Use of Water at Catchment Scale) Project, funded within the EU Fifth Framework Program (2001–2004), constitute inquiry pathways that are explored using a critical incident approach. The initial starting conditions for each inquiry pathway are compared; significant pathway dependencies are identified which foster the development of social learning processes locally, but constrain their uptake and embedding across the wider system of interest. In the first case study, in England & Wales, promising developments in the application of social learning approaches to river basin planning over an initial 3-year period were subsequently marginalised, only to resurface towards the end of the 10-year period of study. In the second, South African case study, significant spaces for social learning and innovation in integrated water resources management were opened up over a five year period but closed down again, primarily as the result of lack of policy support by national government. The third, Italian, case study was designed to assess options for adapting to climate change by opening up new learning spaces between researchers, stakeholders and policy makers. A case for investing in local level systemic innovation through social-learning praxis design approaches and in learning processes around well contextualised case-studies is supported. However, concomitant investment by policy makers in social learning as an alternative, but complementary, governance mechanism for systemic innovation for SD is needed.  相似文献   
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