80 research outputs found
Juice Powder Concentrate and Systemic Blood Pressure, Progression of Coronary Artery Calcium and Antioxidant Status in Hypertensive Subjects: A Pilot Study
Because micronutrients from plants may have beneficial cardiovascular effects, the hypothesis that an encapsulated juice powder concentrate might affect several measures of vascular health was tested in free living adults at low cardiovascular risk. Blood pressure, vascular compliance, lipid and antioxidant markers, and serial electron beam tomography (to calculate a coronary artery calcium score as a measure of atherosclerosis burden), were monitored in 51 pre-hypertensive and hypertensive subjects over 2 years. By the end of follow-up, systolic and diastolic blood pressure decreased significantly (â2.4 ± 1.0âmmHg, P < 0.05 and â2.2 ± 0.6âmmHg, P < 0.001), and large artery compliance improved significantly (1.9 ± 0.6âmlâmmHgâ1 Ă 100, P < 0.01). The progression of coronary artery calcium score was smaller than expected compared with a historical database (P < 0.001). Laboratory testing showed a significant decrease in homocysteine (P = 0.05), HDL cholesterol (P = 0.025) and Apo A (P = 0.004), as well as a significant increase in ÎČ-carotene, folate, Co-Q10 and α-tocopherol (all P < 0.001). The phytonutrient concentrate we utilized induced several favorable modifications of markers of vascular health in the subjects. This study supports the notion that plant nutrients are important components of a heart healthy diet
Diamond (111) surface reconstruction and epitaxial graphene interface
The evolution of the diamond (111) surface as it undergoes reconstruction and
subsequent graphene formation is investigated with angle-resolved photoemission
spectroscopy, low energy electron diffraction, and complementary density
functional theory calculations. The process is examined starting at the
C(111)-(2x1) surface reconstruction that occurs following detachment of the
surface adatoms at 920 {\deg}C, and continues through to the liberation of the
reconstructed surface atoms into a free-standing monolayer of epitaxial
graphene at temperatures above 1000 {\deg}C. Our results show that the
C(111)-(2x1) surface is metallic as it has electronic states that intersect the
Fermi-level. This is in strong agreement with a symmetrically {\pi}-bonded
chain model and should contribute to resolving the controversies that exist in
the literature surrounding the electronic nature of this surface. The graphene
formed at higher temperatures exists above a newly formed C(111)-(2\times1)
surface and appears to have little substrate interaction as the Dirac-point is
observed at the Fermi-level. Finally, we demonstrate that it is possible to
hydrogen terminate the underlying diamond surface by means of plasma processing
without removing the graphene layer, forming a graphene-semiconductor
interface. This could have particular relevance for doping the graphene formed
on the diamond (111)surface via tuneable substrate interactions as a result of
changing the terminating species at the diamond-graphene interface by plasma
processing.Comment: 10 pages, 4 figure
Low-Temperature Growth of Graphene on a Semiconductor
The industrial realization of graphene has so far been limited by challenges related to the quality, reproducibility, and high process temperatures required to manufacture graphene on suitable substrates. We demonstrate that epitaxial graphene can be grown on transition-metal-treated 6H-SiC(0001) surfaces, with an onset of graphitization starting around 450â500 °C. From the chemical reaction between SiC and thin films of Fe or Ru, sp3 carbon is liberated from the SiC crystal and converted to sp2 carbon at the surface. The quality of the graphene is demonstrated by using angle-resolved photoemission spectroscopy and low-energy electron diffraction. Furthermore, the orientation and placement of the graphene layers relative to the SiC substrate are verified by using angle-resolved absorption spectroscopy and energy-dependent photoelectron spectroscopy, respectively. With subsequent thermal treatments to higher temperatures, a steerable diffusion of the metal layers into the bulk SiC is achieved. The result is graphene supported on magnetic silicide or optionally, directly on semiconductor, at temperatures ideal for further large-scale processing into graphene-based device structures
Appropriate referral and selection of patients with chronic pain for spinal cord stimulation: European consensus recommendations and e-health tool
Background: Spinal cord stimulation (SCS) is an established treatment for chronic neuropathic, neuropathic-like and ischaemic pain. However, the heterogeneity of patients in daily clinical practice makes it often challenging to determine which patients are eligible for this treatment, resulting in undesirable practice variations. This study aimed to establish patient-specific recommendations for referral and selection of SCS in chronic pain. Methods: A multidisciplinary European panel used the RAND/UCLA Appropriateness Method (RUAM) to assess the appropriateness of (referral for) SCS for 386 clinical scenarios in four pain areas: chronic low back pain and/or leg pain, complex regional pain syndrome, neuropathic pain syndromes and ischaemic pain syndromes. In addition, the panel identified a set of psychosocial factors that are relevant to the decision for SCS treatment. Results: Appropriateness of SCS was strongly determined by the neuropathic or neuropathic-like pain component, location and spread of pain, anatomic abnormalities and previous response to therapies targeting pain processing (e.g. nerve block). Psychosocial factors considered relevant for SCS selection were as follows: lack of engagement, dysfunctional coping, unrealistic expectations, inadequate daily activity level, problematic social support, secondary gain, psychological distress and unwillingness to reduce high-dose opioids. An educational e-health tool was developed that combines clinical and psychosocial factors into an advice on referral/selection for SCS. Conclusions: The RUAM was useful to establish a consensus on patient-specific criteria for referral/selection for SCS in chronic pain. The e-health tool may help physicians learn to apply an integrated approach of clinical and psychosocial factors. Significance: Determining the eligibility of SCS in patients with chronic pain requires careful consideration of a variety of clinical and psychosocial factors. Using a systematic approach to combine evidence from clinical studies and expert opinion, a multidisciplinary European expert panel developed detailed recommendations to support appropriate referral and selection for SCS in chronic pain. These recommendations are available as an educational e-health tool (https://www.scstool.org/)
The effects of customer equity drivers on loyalty across services industries and firms
Customer equity drivers (CEDs)âvalue equity, brand equity, and relationship equityâpositively affect loyalty intentions, but this effect varies across industries and firms. We empirically examine potential industry and firm characteristics that explain why the CEDsâloyalty link varies across services industries and firms in the Netherlands. The results show that (1) some previously assumed industry and firm characteristics have moderating effects while others do not and (2) firm-level advertising expenditures constitute the most crucial moderator because they influence all three loyalty strategies (significant for value equity and brand equity; marginally significant for relationship equity), while three industry contexts (i.e., innovative markets, visibility to others, and complexity of purchase decisions) each influence two of the three loyalty strategies. Our results clearly show that specific industry and firm characteristics affect the effectiveness of specific loyalty strategies
A Simplified Method for Patterning Graphene on Dielectric Layers
The large-scale formation of patterned, quasi-freestanding graphene structures supported on a dielectric has so far been limited by the need to transfer the graphene onto a suitable substrate and contamination from the associated processing steps. We report ÎŒm scale, few-layer graphene structures formed at moderate temperatures (600â700 °C) and supported directly on an interfacial dielectric formed by oxidizing Si layers at the graphene/substrate interface. We show that the thickness of this underlying dielectric support can be tailored further by an additional Si intercalation of the graphene prior to oxidation. This produces quasi-freestanding, patterned graphene on dielectric SiO2 with a tunable thickness on demand, thus facilitating a new pathway to integrated graphene microelectronics
Predictors of guest retention: Investigating the role of hotelâs corporate social responsibility activities and brand image
Using the conditional grade-of-membership model to assess judgment accuracy
nominal classification, incidental parameters, extreme profiles, mixtures,
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