A General Class of Metamaterial Transformation Slabs

In this paper, we apply transformation-based optics to the derivation of a general class of transparent metamaterial slabs. By means of analytical and numerical full-wave studies, we explore their image displacement/formation capabilities, and establish intriguing connections with configurations already known in the literature. Starting from these revisitations, we develop a number of nontrivial extensions, and illustrate their possible applications to the design of perfect radomes, anti-cloaking devices, and focusing devices based on double-positive (possibly nonmagnetic) media. These designs show that such anomalous features may be achieved without necessarily relying on negative-index or strongly resonant metamaterials, suggesting more practical venues for the realization of these devices.Comment: 25 pages, 13 figures; minor changes in the tex

Immunogenetics of an antigen identified in both sheep and cattle sera.

SUMMARYAlloimmunization in sheep revealed an antigen specificity B1 which is also to be found in cattle sera. The molecular weight of the protein carrying B1 was greater in sheep than in cattle, whilst in both cases its isoelectric point was at pH 6·2. The electrophoretic position of the antigen suggests that the molecule carrying B1 might be a β-globulin. Family studies indicated that in both species B1 was inherited in a simple Mendelian manner, as if it were a product of a dominant alleleB1at an autosomal locusB

Storage time of nut spreads using flash gas chromatography E-nose combined with multivariate data analysis

The quality assessment, in terms of lipid oxidative status, of food products stored in the long-term is of great importance, especially those with a high lipid content. Specifically, companies working in this sector need feasible, simple, and fast techniques that are suitable for quality or process control. Herein, a fingerprinting approach, based on headspace analysis carried out by flash gas chromatography electronic nose (FGC E-nose) and multivariate data analysis was applied to pistachio and gianduja spreads. These samples, differently packaged, were stored in climatic chambers at 40 °C for 180 days and their headspace fraction was analyzed periodically for a total of 15 sampling times. Principal component analysis showed a clear separation according to the packaging type for both pistachio and gianduja samples. Partial least squares regression models were developed to predict the storage time considering the aggregated data (R2 up to 0.985, RMSEP = 6.16 days) or separately (R2 up to 0.989, RMSEP = 5.71 days). Based on the obtained residual prediction deviation (RPD from 4.4 to 8.5 in prediction), the models can be considered suitable for use in quality control in an industrial environment

Literacy Strategies in Middle School Science Classrooms.

This study examined four different scientific literacy strategies and their effectiveness in increasing scientific literacy. These four different strategies include The Learning Cycle Approach, The Venn diagram strategy, the Definition Map, and Science in the News Framework. This study took place with two different eighth grade science classes in the two units of properties of matter and periodic table. The students completed different laboratory activities and ticket out the doors that were assessed to measure the effectiveness of increasing the scientific literacy. The study found that of the four literacy strategies three increased scientific literacy and one did not. The three that supported scientific literacy were The Learning Cycle Approach, The Venn diagram, the Definition Map. The Science in the News Framework did not increase scientific literacy

upper limb rehabilitation robotics after stroke a perspective from the university of padua italy

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Application of a non-targeted approach by Flash Gas Chromatography-E-nose to discriminate the geographical origin of virgin olive oils

One of the fraudulent practices often applied in the olive oil sector concerns the mislabelling of the geographical origin of the products. In order to ensure that consumers are not mislead, the European Union issued a regulation concerning the definition of specific rules for the indication of geographical origin in the label (EU Reg. 29/2012). Beyond the compulsory traceability, the application of specific analytical techniques could be a useful tool to verify the conformity between the product and the information reported on the label. The aim of this work was to evaluate the effectiveness of a Flash Gas Chromatography-E-Nose, an instrument that combines functionality of electronic nose and ultra-fast GC, for the evaluation of the geographical origin of virgin olive oils (VOOs). For this purpose, more than 150 VOOs, different for their geographical origin (from single EU countries, such as Spain, Italy and Greece, and from single extra-EU countries, such as Tunisia, Turkey and Morocco) were collected and analyzed. Subsequently, a chemometric elaboration applied, with a non-targeted approach, to the chromatographic traces was realized. This permitted to build a model able to satisfactorily discriminate samples according to their geographical origin. This work is developed in the context of the project OLEUM \u201cAdvanced solutions for assuring authenticity and quality of olive oil at global scale\u201d, funded by the European Commission within the Horizon 2020 Programme (2014\u20132020, GA no. 635690). The information expressed in this abstract reflects the authors\u2019 views; the EC is not liable for the information contained therein

Children preferences of coloured fresh cheese prepared during an educational laboratory

Choices among young consumers are mainly driven by food preferences; in particular, a connection between appearance and acceptance of food has been highlighted, together with a general lack of knowledge of food processing. For these reasons, educational activities are important to increase scientific knowledge and awareness. The cheese-making educational laboratory described herein involved children, adolescents, and their parents/teachers in the preparation of fresh and naturally-coloured cheeses. At the end of the activity, both the colour preference and possible relation between preference and colour of cheese prepared were investigated administering a short questionnaire

Sensory perception and food neophobia drive liking of functional plant-based food enriched with winemaking by-products

The use of phenol compounds obtained from unripe grapes as antioxidant sustainable food ingredients is challenging due to their specific sensory attributes, such as sourness and astringency. The aim was to evaluate sensory attributes perception and consumers' liking for beetroot purees added with phenols from unripe grapes. According to hedonic responses, consumer clusters were identified and characterized for eating behavioral attitudes. Three hundred two subjects (56% women, 18–60 years old) evaluated sweet, sour, astringency, and overall flavor intensity of and liking for four beetroot puree samples added with increasing phenols concentrations (0–1.93 g/kg). Results showed that liking decreased with increasing phenols. Interestingly, samples with highest phenols concentration, characterized by sourness, and astringency, were preferred by a segment of consumers (39% of the group). This group was characterized by a low food neophobia and tended to have high emotional eating scores compared to consumers preferring samples without or with the lowest amount of extract. These results suggest that the development of functional phenol-enriched products using winemaking by-products is challenging due to their sensory properties that negatively influence consumers' acceptance. However, with appropriate segmentation strategies it is possible to identify specific consumer targets who could appreciate these new functional foods. Practical Applications: Unripe grapes can be used as a sustainable phenol source for the development of new highly antioxidant foods. Indeed, an addition till 1.9 g/kg, besides improving both the nutritional content of the food matrices, as well as promoting the reuse of winemaking by-products, could be considered feasible from a sensory point of view. Specifically, new sustainable plant-based food product, characterized by specific sensory attributes, could be target for specific groups of consumers to foster the transition to the consumption of food products developed using value-added and sustainable ingredients

Characterization of virgin olive oils obtained from minor Tunisian varieties for their valorization

Several compositional parameters (fatty acids, tocopherols, polar phenols and volatiles) in virgin olive oils from varieties located at the center of Tunisia, namely Baldi, Chemchali, Neb Jmel, Tounsi and Besbessi from Gafsa and Chemchali and Sehli cultivated in Sidi Bouzid, were studied. To the best of our knowledge, this is the first study focusing on the chemical composition of virgin olive oils (VOO) from Sidi Bouzid. Significant differences were found between varieties from Sidi Bouzid and Gafsa in monounsaturated saturated fatty acid levels, some volatile compounds and γ-tocopherol amounts. Notably, Tounsi and Baldi VOOs showed the highest six carbon atoms alcohol contents, whereas Neb Jmel VOO revealed the highest aldehyde six carbon atoms content. Fatty acid composition, as well as tocopherol content, showed differences among different VOO. Principal component analysis and hierarchical component analysis on polar phenols, fatty acids, tocopherols and volatiles data evidenced a good discrimination among oils from the different investigated varieties