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991.
The biological activity of mango leaf extracts from different mango varieties was evaluated in terms of total phenolic content, flavonoids, antioxidant activity and inhibition of α-amylase and α-glucosidase enzymes. Leaf extract-based beverages were formulated and evaluated for some physicochemical, microbiological and sensory properties. Results indicated that the extract from 'Tommy Atkins' mango leaves had the highest total phenols content (137.08 mg of GAE g−1) and antioxidant activity (DDPH = 38.26 mg TEAC 100 g−1; ABTS = 59.13 mg TEAC 100 g−1). The beverage formulated with 20% leaf extract presented the highest percentage of antioxidant activity (38.63%) and inhibition of enzymes α-amylase (41.9%) and α-glucosidase (37.53%). All beverages presented a yellow hue and consumers rated it with a degree of liking between 4.8 and 7.3 according to a hedonic scale. Results showed that the biological properties of beverages could be an alternative for the control of free radicals and glucose levels.  相似文献   
992.
Journal of Scheduling - Observations show that some HPC applications periodically alternate between (i) operations (computations, local data accesses) executed on the compute nodes, and (ii) I/O...  相似文献   
993.

Though there are extensive studies on neighborhood effects on health, this relationship remains elusive and requires continuous empirical evidence to support existing findings. Gentrification is a process of neighborhood change that affects most longtime residents. This study examined the health impact of the rapidly changing physical and cultural environment using oral history interviews, electronic interviews, and a quantitative structured survey. The study draws on the social determinants of health framework to explain the self-reported chronic health conditions (SR-CHCs) among 331 residents in Austin, Texas. The study employed non-linear techniques suitable for Poisson distribution to estimate the association between gentrification and SR-CHCs and complemented by direct quotes from in-depth interviews (IDIs). Perceived gentrification score significantly vary by marital status (p?<?0.001), educational attainment (p?<?0.001), and gender (p?<?0.01), while SR-CHCs only significantly varies by educational attainment, p?=?0.015). Multivariate results show that gentrification was positively associated with SR-CHCs, after adjusting for socioeconomic variables. Compared to the Hispanics, blacks were 97% more likely to report multiple counts of SR-CHCs (IRR?=?1.969, 95% CI 1.074–3.608), and participants with high household income were 8% less likely to report multiple CHCs (IRR?=?0.920, 95% CI 0.870–0.973). Drawing from the empirical findings, this study recommends both area-based and individual-level policies to mitigate neighborhood change's impact on residents' health. Finally, this study further adds to the understanding of social determinants of health in understanding chronic health within the changing urban physical and socio-ecology systems.

  相似文献   
994.
Engineering of the cooling mechanism is of primary importance for the development of nanoelectronics. While radiation cooling is rather inefficient in current electronic devices, the strong anisotropy of 2D materials allows for enhanced efficiency because their hyperbolic electromagnetic dispersion near phonon resonances allows them to sustain much larger (≈105) number of radiating channels. In this review, radiation cooling in 2D materials is addressed. The hyperbolic dispersion of electromagnetic waves is presented, and how the spontaneous fluctuations in current in a 2D electronic channel can radiate thermal energy in its hyperbolic surrounding medium is described. Both the regime of thermal current fluctuations and out‐of‐equilibrium current fluctuations can be described within the same framework leading to superPlanckian thermal emission and electroluminescent cooling. A recent experimental investigation on graphene‐on‐hBN transistors using electronic noise thermometry is discussed. In high mobility semimetal‐like graphene at large bias, a steady‐state out‐of‐equilibrium situation is caused by Zener tunneling of electrons, opening a route for electroluminescence of hyperbolic electromagnetic modes. Electroluminescent cooling is particularly prominent once the Zener tunneling regime is reached: observed cooling powers are nine orders of magnitude larger than in conventional LEDs.  相似文献   
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Indices of geochemical zonality (Vz) of multielements around mineral deposits and their spatial associations with particular geological, geochemical, and structural factors are critical aspects that must be considered in mineral exploration. Values of Vz indices allow distinction between sub-ore and supra-ore anomalies, which are associated with outcropping and blind deposits, respectively. In this paper, we used a map of a Vz index (Zn?Pb/Cu*Ag) in weights-of-evidence analysis of regional-scale prospectivity for porphyry-Cu deposits in the area covered by 1:100,000 scale map sheet of Jebal-Barez (Kerman province, southern Iran). For comparison, we used a Cu map instead of the Vz map in the weights-of-evidence (WofE) analysis. The Vz-in-WofE prospectivity model outperforms the Cu-in-WofE prospectivity model. In fact, prior to writing this paper, blind porphyry-Cu mineralization was intersected at depth by borehole exploration in a high prospectivity zone delineated by the Vz-in-WofE model. The results demonstrate the usefulness of the Vz-in-WofE for regional-scale targeting of blind mineral deposits.  相似文献   
998.
A major challenge in creating and optimizing therapeutics in the fight against cancer is visualizing and understanding the microscale spatiotemporal treatment response dynamics that occur in patients. This is especially true for photodynamic therapy (PDT), where therapeutic optimization relies on understanding the interplay between factors such as photosensitizer localization and uptake, in addition to light dose and delivery rate. In vitro 3D culture systems that recapitulate many of the biological features of human disease are powerful platforms for carrying out detailed studies on PDT response and resistance. Current techniques for visualizing these models, however, often lack accuracy due to the perturbative nature of the sample preparation, with light attenuation complicating the study of intact models. Optical coherence tomography (OCT) is an ideal method for the long-term, non-perturbative study of in vitro models and their response to PDT. Monitoring the response of 3D models to PDT by time-lapse OCT methods promises to provide new perspectives and open the way to cancer treatment methodologies that can be translated towards the clinic.  相似文献   
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The Journal of Supercomputing - With the development of the cloud computing market, cloud computing providers are offering to their users the flexibility to choose the desired capacity of both...  相似文献   
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