7,154 research outputs found
2-C*-categories with non-simple units
We study the general structure of 2-C*-categories closed under conjugation,
projections and direct sums. We do not assume units to be simple, i.e. for i_A
the 1-unit corresponding to an object A, the space Hom(i_A, i_A) is a
commutative unital C*-algebra. We show that 2-arrows can be viewed as
continuous sections in Hilbert bundles and describe the behaviour of the fibres
with respect to the categorical structure. We give an example of a
2-C*-Category giving rise to bundles of finite Hopf-algebras in duality. We
make some remarks concerning Frobenius algebras and Q-systems in the general
context of tensor C*-categories with non-simple units.Comment: 47 page
Still the century of ‘new’ environmental policy instruments? Exploring patterns of innovation and continuity
This article re-examines the political interest in and use of ‘new' environmental policy instruments (NEPIs) and other non-regulatory modes of governance. It starts by taking stock of the dynamic debate that has emerged around this topic since the turn of the century. It then contextualizes that debate by examining subsequent challenges to, and transformations in state-led governing and the widely acknowledged rise of 'new governance' more generally. It highlights the mismatch between: (a) the animated discussion of new instruments amongst policy makers and academics; and (b), the less active adoption and performance of them in practice. It makes an overall assessment of the role of instruments - both ‘old' and ‘new' - in the wider debate about governance, and suggests some steps that could be taken by both practitioners and scholars better to understand and possibly even utilise more NEPIs in the future
Design and development of a multipurpose, boresighted star tracker
Design and development of boresighted star tracke
An Analytic Hierarchy Process for The Evaluation of Transport Policies to Reduce Climate Change Impacts
Transport is the sector with the fastest growth of greenhouse gases emissions, both in developed and in developing countries, leading to adverse climate change impacts. As the experts disagree on the occurrence of these impacts, by applying the analytic hierarchy process (AHP), we have faced the question on how to form transport policies when the experts have different opinions and beliefs. The opinions of experts have been investigated by a means of a survey questionnaire. The results show that tax schemes aiming at promoting environmental-friendly transport mode are the best policy. This incentives public and environmental-friendly transport modes, such as car sharing and car pooling.Analytic Hierarchy Process, Transport Policies, Climate Change
Ketogenic diet-induced weight loss is associated with an increase in vitamin d levels in obese adults
Vitamin D is an important micronutrient involved in several processes. Evidence has shown a strong association between hypovitaminosis D and cardio-metabolic diseases, including obesity. A ketogenic diet has proven to be very effective for weight loss, especially in reducing fat mass while preserving fat-free mass. The aim of this study was to investigate the effect of a ketogenic diet-induced weight loss on vitamin D status in a population of obese adults. We enrolled 56 obese outpatients, prescribed with either traditional standard hypocaloric Mediterranean diet (SHMD) or very low-calorie ketogenic diet (VLCKD). Serum 25(OH)D concentrations were measured by chemiluminescence. The mean value of serum 25-hydroxyvitamin D (25(OH)D) concentrations in the whole population at baseline was 17.8 +/- 5.6 ng/mL, without differences between groups. After 12 months of dietetic treatment, in VLCKD patients serum 25(OH)D concentrations increased from 18.4 +/- 5.9 to 29.3 +/- 6.8 ng/mL (p < 0.0001), vs 17.5 +/- 6.1 to 21.3 +/- 7.6 ng/mL (p = 0.067) in the SHMD group (for each kilogram of weight loss, 25(OH)D concentration increased 0.39 and 0.13 ng/mL in the VLCKD and in the SHMD groups, respectively). In the VLCKD group, the increase in serum 25(OH)D concentrations was strongly associated with body mass index, waist circumference, and fatty mass variation. In a multiple regression analysis, fatty mass was the strongest independent predictor of serum 25(OH)D concentration, explaining 15.6%, 3.3%, and 9.4% of its variation in the whole population, in SHMD, and VLCKD groups, respectively. We also observed a greater reduction of inflammation (evaluated by high-sensitivity C reactive protein (hsCRP) values) and a greater improvement in glucose homeostasis, confirmed by a reduction of HOMA values, in the VLCKD versus the SHMD group. Taken together, all these data suggest that a dietetic regimen, which implies a great reduction of fat mass, can improve vitamin D status in the obese
Effects of age and eccentricity on visual target detection
The aim of this study was to examine the effects of aging and target eccentricity on a visual search task comprising 30 images of everyday life projected into a hemisphere, realizing a ±90° visual field. The task performed binocularly allowed participants to freely move their eyes to scan images for an appearing target or distractor stimulus (presented at 10°; 30°, and 50° eccentricity). The distractor stimulus required no response, while the target stimulus required acknowledgment by pressing the response button. One hundred and seventeen healthy subjects (mean age = 49.63 years, SD = 17.40 years, age range 20–78 years) were studied. The results show that target detection performance decreases with age as well as with increasing eccentricity, especially for older subjects. Reaction time also increases with age and eccentricity, but in contrast to target detection, there is no interaction between age and eccentricity. Eye movement analysis showed that younger subjects exhibited a passive search strategy while older subjects exhibited an active search strategy probably as a compensation for their reduced peripheral detection performance
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