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991.
992.
Paul H. Falcone Aaron C. Tribby Roxanne M. Vogel Jordan M. Joy Jordan R. Moon Chantelle A. Slayton Micah M. Henigman Joanne A. Lasrado Brandon J. Lewis Brenda A. Fonseca Kristin M. Nieman Kelli A. Herrlinger 《Journal of the International Society of Sports Nutrition》2018,15(1):58
Background
Proprietary spearmint extract (PSE) containing a minimum 14.5% rosmarinic acid and 24% total phenolic content, has evinced positive effects on cognition in individuals aged 50–70 with memory impairment after chronic supplementation. To address the growing interest in connecting mental and physical performance, the present study examined whether the nootropic effects of PSE translate into changes in reactive agility following daily supplementation with PSE.Methods
Utilizing a randomized, double-blind, placebo-controlled, parallel design, healthy, recreationally-active men and women (n?=?142) received 900?mg of PSE or placebo (PLA) daily for 90?days. Reactive agility, our primary outcome, was determined by measuring the number of hits and average reaction time (ART) on a Makoto Arena II, a 3600 audio-visual device that measures stationary, lateral, and multi-directional active choice reaction performance. Safety was evaluated using complete blood count, comprehensive metabolic panel, and blood lipids. Measurements were evaluated on days 7, 30, and 90 of supplementation.Results
An overall treatment effect (p?=?0.019) was evident for increased hits with PSE on the stationary test with footplates, with between group differences at Day 30 (PSE vs. PLA: 28.96?±?2.08 vs. 28.09?±?1.92 hits; p?=?0.040) and Day 90 (PSE vs. PLA: 28.42?±?2.54 vs. 27.02?±?3.55 hits; p?=?0.002). On the same task, ART improved (treatment effect, p?=?0.036) with PSE at Day 7 (PSE vs. PLA: 0.5896?±?0.060 vs. 0.6141?±?0.073?s; p?=?0.049) and Day 30 (PSE vs. PLA: 0.5811?±?0.068 vs. 0.6033?±?0.055?s; p?=?0.049). PSE also significantly increased hits (treatment effect, p?=?0.020) at Day 30 (PSE vs. PLA: 19.25?±?1.84 vs. 18.45?±?1.48 hits; p?=?0.007) and Day 90 (PSE vs. PLA: 19.39?±?1.90 vs. 18.66?±?1.64 hits; p?=?0.026) for the multi-directional test with footplates. Significant differences were not observed in the remaining Makoto tests. PSE was well tolerated as evidenced by no effects observed in the blood safety panels.Conclusions
The findings of the current study demonstrate that consumption of 900?mg of PSE improved specific measures of reactive agility in a young, active population.Trial registration
clinicaltrials.gov, NCT02518165. Registered August 7, 2015 – retrospectively registered.993.
Anne E. Winters Andrew M. White Ariyanti S. Dewi I. Wayan Mudianta Nerida G. Wilson Louise C. Forster Mary J. Garson Karen L. Cheney 《Journal of chemical ecology》2018,44(4):384-396
Many plants and animals store toxic or unpalatable compounds in tissues that are easily encountered by predators during attack. Defensive compounds can be produced de novo, or obtained from dietary sources and stored directly without selection or modification, or can be selectively sequestered or biotransformed. Storage strategies should be optimized to produce effective defence mechanisms but also prevent autotoxicity of the host. Nudibranch molluscs utilize a diverse range of chemical defences, and we investigated the accumulation and distribution of defensive secondary metabolites in body tissues of 19 species of Chromodorididae nudibranchs. We report different patterns of distribution across tissues, where: 1) the mantle had more or different (but structurally related) compounds than the viscera; 2) all compounds in the mantle were also in the viscera; and 3) the mantle had fewer compounds than the viscera. We found no further examples of species that selectively store a single compound, previously reported in Chromodoris species. Consistent with other studies, we found high concentrations of metabolites in mantle rim tissues compared to the viscera. Using bioassays, compounds in the mantle were more toxic than compounds found in the viscera for Glossodoris vespa Rudman, 1990 and Ceratosoma brevicaudatum Abraham, 1876. In G. vespa, compounds in the mantle were also more unpalatable to palaemonid shrimp than compounds found in the viscera. This indicates that these species may modify compounds to increase bioactivity for defensive purposes and/or selectively store more toxic compounds. We highlight clear differences in the storage of sequestered chemical defences, which may have important implications for species to employ effective defences against a range of predators. 相似文献
994.
Silvia Casotto Frdric Pascon Anne Marie Habraken Stefania Bruschi 《International Journal of Machine Tools and Manufacture》2005,45(6):657-664
The paper presents a validated numerical model able to predict geometrical distortions of rings during cooling phase after hot ring rolling operations. The model is capable to take into account the effects of all the phenomena resulting from the coupling of thermal, mechanical and metallurgical events. As simulation results strongly depend on the accuracy of input data, physical simulation experiments on real-material samples are developed and carried out to characterize material behaviour during phase transformation.The numerical model is then validated by an industrial case proving its effectiveness in predicting final ring distortions at room temperature. 相似文献
995.
A comparison of the corrosion behavior of WC-Co-Cr and WC-Co HVOF thermally sprayed coatings by in situ atomic force microscopy (AFM) 总被引:1,自引:0,他引:1
The corrosion behavior of WC-Co-Cr and WC-Co high velocity oxygen fuel (HVOF) sprayed coatings were examined in static saline
conditions. Direct current (DC) polarization tests were conducted and the electrochemical corrosion behavior was shown, by
in situ atomic force microscopy (AFM) and scanning electron microscopy (SEM), to be complex because of the composite ceramic-metal
nature of the coating. The addition of chromium to the matrix greatly enhanced the corrosion resistance of the coating. 相似文献
996.
This paper presents a cost-based assessment of the effectiveness of Smart Substrate MCM Systems. A Smart Substrate MCM System is one in which the substrate contains active circuitry for carrying out testing functions. The feasibility of using this approach is investigated. The Smart Substrate strategy is compared to an alternative approach based on the assumption that system components are perfect (Known Good Die (KGD) approach). The obtained results identify the domain of applicability of Smart substrate MCMs and point to limitations of the KGD approach. 相似文献
997.
Kristin M. Schild Robert L. Hawley Jonathan W. Chipman Douglas I. Benn 《International journal of remote sensing》2017,38(23):6865-6881
Marine-terminating outlet glaciers discharge mass through iceberg calving, submarine melting, and meltwater run-off. While calving can be quantified by in situ and remote-sensing observations, meltwater run-off, the subglacial transport of meltwater, and submarine melting are not well constrained due to inherent difficulties observing the subglacial and proglacial environments at tidewater glaciers. Remote-sensing and in situ measurements of surface sediment plumes, and their suspended sediment concentration (SSC), have been used as a proxy for glacier meltwater run-off. However, this relationship between satellite reflectance and SSC has predominantly been established using land-terminating glaciers. Here, we use two Svalbard tidewater glaciers to establish a well-constrained relationship between Landsat-8 surface reflecance and SSC and argue that it can be used to measure relative meltwater run-off at tidewater glaciers throughout a summer melt season. We find the highest correlation between SSCs and Landsat-8 surface reflectance by using the red + NIR band combination (r2 = 0.76). The highest correlation between SSCs and in situ field spectrometer measurements is in the 740–800 nm wavelength range (r2 = 0.85), a spectral range not currently measured by Landsat. Additionally, we find that in situ and Landsat-8 measurements for surface reflectance of SSCs are not interchangeable and therefore establish a relationship for each detection method. We then use the Landsat-8 relationship to calculate total surface sediment load, finding a strong correlation between total surface sediment load and a proxy for meltwater run-off (r2 ≥ 0.89). Our results establish a new metric to calculate SSCs from Landsat-8 surface reflectance and demonstrate how the SSC of subglacial sediment plumes can be used to monitor relative seasonal meltwater discharge at tidewater glaciers. 相似文献
998.
Xinjuan?Chen Jae-Hun?JungEmail author Anne?Gelb 《Journal of scientific computing》2018,76(2):1127-1147
In several applications, data are collected in the frequency (Fourier) domain non-uniformly, either by design or as a consequence of inexact measurements. The two major bottlenecks for image reconstruction from non-uniform Fourier data are (i) there is no obvious way to perform the numerical approximation, as the non-uniform Fourier data is not amenable to fast transform techniques and resampling the data first to uniform spacing is often neither accurate or robust; and (ii) the Gibbs phenomenon is apparent when the underlying function (image) is piecewise smooth, an occurrence in nearly every application. Recent investigations suggest that it may be useful to view the non-uniform Fourier samples as Fourier frame coefficients when designing reconstruction algorithms that attempt to mitigate either of these fundamental problems. The inverse polynomial reconstruction method (IPRM) was developed to resolve the Gibbs phenomenon in the reconstruction of piecewise analytic functions from spectral data, notably Fourier data. This paper demonstrates that the IPRM is also suitable for approximating the finite inverse Fourier frame operator as a projection onto the weighted \(L_2\) space of orthogonal polynomials. Moreover, the IPRM can also be used to remove the Gibbs phenomenon from the Fourier frame approximation when the underlying function is piecewise smooth. The one-dimensional numerical results presented here demonstrate that using the IPRM in this way yields a robust, stable, and accurate approximation from non-uniform Fourier data. 相似文献
999.
The opportunities of open data have been recently recognized among companies in different domains. Digital service providers have increasingly been interested in the possibilities of innovating new ideas and services around open data. Digital service ecosystems provide several advantages for service developers, enabling the service co-innovation and co-creation among ecosystem members utilizing and sharing common assets and knowledge. The utilization of open data in digital services requires new innovation practices, service development models, and a collaboration environment. These can be provided by the ecosystem. However, since open data can be almost anything and originate from different kinds of data sources, the quality of data becomes the key issue. The new challenge for service providers is how to guarantee the quality of open data. In the ecosystems, uncertain data quality poses major challenges. The main contribution of this paper is the concept of the Evolvable Open Data based digital service Ecosystem (EODE), which defines the kinds of knowledge and services that are required for validating open data in digital service ecosystems. Thus, the EODE provides business potential for open data and digital service providers, as well as other actors around open data. The ecosystem capability model, knowledge management models, and the taxonomy of services to support the open data quality certification are described. Data quality certification confirms that the open data is trustworthy and its quality is good enough to be accepted for the usage of the ecosystem’s services. The five-phase open data quality certification process, according to which open data is brought to the ecosystem and certified for the usage of the digital service ecosystem members using the knowledge models and support services of the ecosystem, is also described. The initial experiences of the still ongoing validation steps are summarized, and the concept limitations and future development targets are identified. 相似文献
1000.
André Calero Valdez Juliana Brell Anne Kathrin Schaar Martina Ziefle 《Universal Access in the Information Society》2018,17(3):549-566
In times of demographic change, skill shortage and disruptive innovations, organizational knowledge management and innovative capacity are the key to a company’s success. But how can knowledge be retained with fast staff turnover, global project-based work and parental leaves? Using enterprise social media to improve knowledge dissemination at work seems promising, when looking at the success of private social networking sites. In this article we combine ten different empirical studies which investigated different aspects of how user diversity influences the motivation to use social media at work. The emerging meta-study using the DerSimonian–Laird method (total sample size \(N=522\)) analyzes different aspects of user diversity and their correlation with eight motives for SNS usage: information, importance, contact, self-presentation, autonomy, social comparison, and power and control. We found that that the individual achievement motivation correlates positively with the motives importance, power, information and self-presentation. The need for autonomy correlates with openness to new experiences and the need for social comparison with gender and neuroticism. From our findings, we derive practical implications for designing a social networking site for work which fulfills the users’ needs and functions along their motivation. 相似文献