48 research outputs found

    School nutrition guidelines: overview of the implementation and evaluation

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    Objective To holistically evaluate the extent of implementation of dietary guidelines in schools and present various monitoring systems. Design The study comprises three methods: (i) a cross-sectional survey (process evaluation); (ii) an indicator-based evaluation (menu quality); and (iii) a 5 d weighed food record of school lunches (output evaluation). Setting Slovenian primary schools. Subjects A total 234 food-service managers from 488 schools completed a self-administrated questionnaire for process evaluation; 177 out of 194 randomly selected schools provided menus for menu quality evaluation; and 120 school lunches from twenty-four schools were measured and nutritionally analysed for output evaluation. Results The survey among food-service managers revealed high levels of implementation at almost all process evaluation areas of the guidelines. An even more successful implementation of these guidelines was found in relation to organization cultural issues as compared with technical issues. Differences found in some process evaluation areas were related to location, size and socio-economic characteristics of schools. Evaluation of school menu quality demonstrated that score values followed a normal distribution. Higher (better) nutrition scores were found in larger-sized schools and corresponding municipalities with higher socio-economic status. School lunches did not meet minimum recommendations for energy, carbohydrates or dietary fibre intake, nor for six vitamins and three (macro, micro and trace) elements. Conclusions The implementation of the guidelines was achieved differently at distinct levels. The presented multilevel evaluation suggests that different success in implementation might be attributed to different characteristics of individual schools. System changes might also be needed to support and improve implementation of the guidelines

    Quantum gates and quantum algorithms with Clifford algebra technique

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    We use our Clifford algebra technique, that is nilpotents and projectors which are binomials of the Clifford algebra objects γa\gamma^a with the property {γa,γb}+=2ηab\{\gamma^a,\gamma^b\}_+ = 2 \eta^{ab}, for representing quantum gates and quantum algorithms needed in quantum computers in an elegant way. We identify nn-qubits with spinor representations of the group SO(1,3) for a system of nn spinors. Representations are expressed in terms of products of projectors and nilpotents. An algorithm for extracting a particular information out of a general superposition of 2n2^n qubit states is presented. It reproduces for a particular choice of the initial state the Grover's algorithm.Comment: 9 pages, revte

    The jumping spider Saitis barbipes lacks a red photoreceptor to see its own sexually dimorphic red coloration

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    Examining the role of color in mate choice without testing what colors the study animal is capable of seeing can lead to ill-posed hypotheses and erroneous conclusions. Here, we test the seemingly reasonable assumption that the sexually dimorphic red coloration of the male jumping spider Saitis barbipes is distinguishable, by females, from adjacent black color patches. Using microspectrophotometry, we find clear evidence for photoreceptor classes with maximal sensitivity in the UV (359 nm) and green (526 nm), inconclusive evidence for a photoreceptor maximally sensitive in the blue (451 nm), and no evidence for a red photoreceptor. No colored filters within the lens or retina could be found to shift green sensitivity to red. To quantify and visualize whether females may nevertheless be capable of discriminating red from black color patches, we take multispectral images of males and calculate photoreceptor excitations and color contrasts between color patches. Red patches would be, at best, barely discriminable from black, and not discriminable from a low-luminance green. Some color patches that appear achromatic to human eyes, such as beige and white, strongly absorb UV wavelengths and would appear as brighter “spider-greens” to S. barbipes than the red color patches. Unexpectedly, we discover an iridescent UV patch that contrasts strongly with the UV-absorbing surfaces dominating the rest of the spider. We propose that red and black coloration may serve identical purposes in sexual signaling, functioning to generate strong achromatic contrast with the visual background. The potential functional significance of red coloration outside of sexual signaling is discussed

    How Did the Spider Cross the River? Behavioral Adaptations for River-Bridging Webs in Caerostris darwini (Araneae: Araneidae)

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    Interspecific coevolution is well described, but we know significantly less about how multiple traits coevolve within a species, particularly between behavioral traits and biomechanical properties of animals' "extended phenotypes". In orb weaving spiders, coevolution of spider behavior with ecological and physical traits of their webs is expected. Darwin's bark spider (Caerostris darwini) bridges large water bodies, building the largest known orb webs utilizing the toughest known silk. Here, we examine C. darwini web building behaviors to establish how bridge lines are formed over water. We also test the prediction that this spider's unique web ecology and architecture coevolved with new web building behaviors.We observed C. darwini in its natural habitat and filmed web building. We observed 90 web building events, and compared web building behaviors to other species of orb web spiders.Caerostris darwini uses a unique set of behaviors, some unknown in other spiders, to construct its enormous webs. First, the spiders release unusually large amounts of bridging silk into the air, which is then carried downwind, across the water body, establishing bridge lines. Second, the spiders perform almost no web site exploration. Third, they construct the orb capture area below the initial bridge line. In contrast to all known orb-weavers, the web hub is therefore not part of the initial bridge line but is instead built de novo. Fourth, the orb contains two types of radial threads, with those in the upper half of the web doubled. These unique behaviors result in a giant, yet rather simplified web. Our results continue to build evidence for the coevolution of behavioral (web building), ecological (web microhabitat) and biomaterial (silk biomechanics) traits that combined allow C. darwini to occupy a unique niche among spiders

    Radon decay products and 10–1100 nm aerosol particles in Postojna Cave

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    At the lowest point along the tourist route in Postojna Cave, the activity concentration of radon (222Rn) decay products and the number concentration and size distribution of aerosol particles in the size range of 10–1100 nm were monitored, with the focus on the unattached fraction (fun) of radon decay products (RnDPs), a key parameter in radon dosimetry. The total number concentration of aerosols during visits in summer was lower (700 cm−3) than in winter (2800 cm−3), and was dominated by 50 nm particles (related to the attached RnDPs) in winter. This explains the higher fun values in summer (0.75) and the lower winter measurement (0.04) and, consequently, DCFD values of 43.6 and 13.1 mSv WLM−1 respectively for the calculated dose conversion factors. The difference is caused by an enhanced inflow of fresh outside air, driven in winter by the higher air temperature in the cave compared to outside, resulting in the introduction of outside aerosol particles into the cave

    Nephila female gigantism attained through post-maturity molting

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    10.1636/B12-03.1Journal of Arachnology403345-34
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