An educational path for the magnetic vector potential and its physical implications

We present an educational path on the magnetic vector potential A addressed to undergraduate students and to pre-service physics teachers. Starting from the generalized Ampere-Laplace law, in the framework of a slowly varying time-dependent field approximation, the magnetic vector potential is written in terms of its empirical referent, i. e. the conduction current. Therefore, once the currents are known, our approach allows a clear and univocal physical determination of A overcoming the mathematical indeterminacy due to the gauge transformations. We have no need to fix a gauge, since for slowly varying time-dependent electric and magnetic fields, the natural gauge for A is the Coulomb one. We stress the difference between our approach and those usually presented in the literature. Finally, a physical interpretation of the magnetic vector potential is discussed and some examples of calculation of A are analysed

The explicative power of the vector potential for superconductivity: a path for high school

In the classroom practice the notion of the magnetic vector potential is never introduced, both because it is not contained in secondary school textbooks and because teachers usually associate this concept with complex topics they dealt with in their university courses. In our experience instead, we have found that the introduction of the vector potential can be of great help in students’ understanding of electromagnetism and modern physics topics. In this paper we will show how the use of the vector potential allows a phenomenological and consistent explanation of superconductivity at a level suitable for high school students. We will deal with the two main aspects of superconductivity: the resistivity of the superconductor that drops to zero at the critical temperature and the expulsion of the magnetic field from the bulk of a superconductor (Meissner effect). By the use of the vector potential, students can build a phenomenological interpretation of superconductivity, always remaining in the frame of electromagnetism and thus avoiding the use of too complicated mathematical tools that the explanation of the microscopic mechanism would require

Characterization of Food Products by Chemical, Physical and Sensory Properties: a Combined Approach

The aim of this doctoral dissertation is to show the results of a combined approach related to the characterization of food products by chemical, physical and sensory properties. The two main objectives are the discrimination of food products, according to analytical characteristics (chemical, physical and sensory) and related to compositional and/or technological variables, and the relationship study between the sensory profile and some chemical-physical characteristics used for valorization and quality testing of a food product. The research method leads to investigate the main drivers of the consumer's overall liking. The strategy implemented highlights the effectiveness of sensory and instrumental methodologies in food quality investigation due to the complementary information that they can provide. Some trials are related to the study on sunflower and hazelnut cold-pressed oils, the investigation on the effectiveness of the Flash Gas Chromatography Electronic Nose (FGC E-nose) as a tool to rapidly discriminate among commercial virgin olive oils, the characterization of Taralli, the characterization of different commercial categories of Italian cooked hams, the quality evaluation and consumers’ acceptance of a set of different extra virgin olive oils purchased on the Italian market, and the possible influence of aromatization process on the quality of “flavored olive oils”. The obtained results feature specific sensory attributes and chemical-physical properties that contribute to better defining product characteristics, the perception of food quality and its typicality. These investigations highlight the importance of familiarity with the products and eating habits in the definition of consumer behavior. The findings reveal an important insight for which additional efforts should be addressed towards dissemination of accurate information about the relationship between product composition and sensory characteristics

A Design Strategy Based on Topology Optimization Techniques for an Additive Manufactured High Performance Engine Piston

In this paper, a methodology for the design of a motorcycle piston is presented, based on topology optimization techniques. In particular, a design strategy is preliminary investigated aiming at replacing the standard aluminum piston, usually manufactured by forging or casting, with an alternative one made of steel and manufactured via an Additive Manufacturing process. In this methodology, the minimum mass of the component is considered as the objective function and a target stiffness of important parts of the piston is employed as a design constraint. The results demonstrate the general applicability of the methodology presented for obtaining the geometrical layout and thickness distribution of the structure

Sensory Analysis of Virgin Olive Oil

Virgin olive oil (VOO) is the supernatant of the fresh juice obtained from olives by crushing, pressure and centrifugation, without additional refining. Its flavour is characteristic and is markedly different from those of other edible fats and oils. The combined effect of odour (directly via the nose or indirectly through a retronasal path, via the mouth), taste and chemical responses (as pungency) gives rise to the sensation generally perceived as “flavour”. Sensory analysis is an essential technique to characterize food and investigate consumer preferences. International cooperative studies, supported by the International Olive Oil Council (IOOC) have provided a sensory codified methodology for VOOs, known as the “COI Panel test”. Such an approach is based on the judgments of a panel of assessors, conducted by a panel leader, who has sufficient knowledge and skills to prepare sessions of sensory analysis, motivate judgement, process data, interpret results and draft the report. The panel generally consists of a group of 8 to 12 persons, selected and trained to identify and measure the intensity of the different positive and negative sensations perceived. Sensory assessment is carried out according to codified rules, in a specific tasting room, using controlled conditions to minimize external influences, using a proper tasting glass and adopting both a specific vocabulary and a profile sheet that includes positive and negative sensory attributes (Dec-23/98-V/2010). Collection of the results and statistical elaboration must be standardized (EEC Reg. 2568/91, EC Reg. 640/08). The colour of VOO, which is not significantly related to its quality, may produce expectations and interferences in the flavour perception phase. In order to eliminate any prejudices that may affect the smelling and tasting phases, panelists use a dark-coloured (blue or amber-coloured) tasting glass. Many chemical parameters and sensory analyses (EEC Reg. 2568/91 and EC Reg. 640/08), with the latter carried out by both olfactory and gustatory assessments, can classify oils in different quality categories (extra virgin, virgin, lampant). Extra virgin olive oil (EVOO) extracted from fresh and healthy olive fruits (Olea europaea L.), properly processed and adequately stored, is characterized by an unique and measurable combination of aroma and taste. Moreover, the category of EVOO should not show any defects (e.g. fusty, musty, winey, metallic, rancid) that can originate from incorrect production or storage procedures. Positive or negative sensory descriptors of VOO have been related to volatile and phenol profiles, which are responsible for aroma and taste, respectively. The characteristic taste of VOO, and in particular some positive attributes such as bitterness and pungency that are related to important health benefits, is not completely understood or appreciated by consumers. In this respect, it is interesting to consider the degree of acceptability of VOO in several countries based on literature data. In this way, it is possible to lay the foundations for correct instruction of the sensory characteristics of EVOO. The main chemical, biochemical and technological processes responsible for the positive and negative (defects) descriptors of VOO are summarized in this chapter. An overview on the sensory methodologies proposed, applied and modified during the last 20 years is also presented

Education in anesthesia: three years of online logbook implementation in an Italian school

BACKGROUND: The progress of physicians through residency training in anesthesiology can be monitored using an online logbook. The aim of this investigation was to establish how residents record clinical activities in their computerized web-based logbooks during their first years of anesthesiology training. METHODS: For this retrospective observational trial, the ESSE 3(©) digital registry of the University of Modena and Reggio Emilia, Italy was used to record all anesthesia-related activities performed by three consecutive year-groups of residents (Groups A, B and C) between 2009 and 2012. The ratio of activities to sessions was chosen as a surrogate measure of compliance. RESULTS: A total of 41,348 actions were analyzed. The ratio of activities to sessions showed a statistically significant decline for all activities concerning the perioperative management of anesthesia, with a steady reduction from the first to the last year-group (Group A 23.7, Group B 14.1 and Group C 2.2; p = 0.003). CONCLUSIONS: An online activities logbook is a useful tool for recording and assessing the clinical activities undertaken by each resident during residency training in anesthesiology

Introducing a Framework to Assess Agritourism’s Impact on Agricultural Literacy and Consumer Behavior towards Local Foods

Agritourism operators frequently incorporate educational opportunities about agricultural products and farming in their tourism experiences, but the educational potential of agritourism on visitors has not been measured. This potential impact of agritourism is important considering the environmental and economic sustainability of food systems depend on agriculturally literate citizens and policymakers. The purpose of this work is to develop a theoretical and methodological framework that will help determine the role of agritourism experiences in influencing agricultural literacy and local food purchasing behavior among consumers. To achieve this purpose, this work will account for the potential for agritourism experiences to impact both children and their parents, stimulating an intergenerational transfer of knowledge and subsequent increase in consumers’ purchasing of locally produced agricultural products

Does poor stunning affect the assessment of animal-based measures consciousness in lambs at slaughter?

Oral session 2[EN] According to EU legislation on the killing of animals (EC n. 1099/2009), to ensure that animals do not regain consciousness before slaughter, the efficiency of stunning method must be evaluated through animal-based measures (ABMs)

Recognised-by-law versus other identification systems in pigs: piglets discomfort evaluation and performance testing

The aim of the study was to evaluate the performance of recognised by Italian law (tattoos) and other (ear tags and injectable transponders) identification systems and to investigate if they caused different levels of short-term discomfort in piglets. Ninety-six ten-day-old piglets – equally assigned to four experimental groups – were identified with electronic ear tags (EET), transponders injected in the auricle base (TAB), in intraperitoneal position (TIP), or ear tattoo (T). Losses, breakages and readability of the identification devices were recorded to evaluate their efficiency. Forty-eight piglets were observed continuously for 5 min after identification. Behavioural indicators of pain, discomfort or ease were recorded in terms of duration of occurrence or frequency. Non-parametric analyses of variance were used to compare time required for the application of the devices and behavioural reactions of piglets. No healing problems or breakages of the electronic devices were observed during the trial. The readability after nine months was 93.8% for EET and TIP, 86.7% for TAB and 0% for T. The time required for the application differed significantly (P<0.001) among the four identification devices. EET and TIP showed better results than T considering losses, breakages, readability and time required for application. Behaviours most frequently recorded were head shaking and ear scratching, observed more frequently in piglets after the application of EET (P<0.001). The application of these identification devices caused a mild discomfort in piglets; further studies should investigate in detail the intensity and duration of reactions to the identification procedure

Cost-effectiveness analysis of different seasonal influenza vaccines in the elderly Italian population

In the perspective of reaching at least 75% influenza vaccination coverage in the elderly and substantial budget constraints, Italian decision makers are facing important challenges in determining an optimal immunization strategy for this growing and particularly vulnerable population. Four different influenza vaccines are currently available for Italian older adults aged 65&nbsp;years or above, namely trivalent inactivated vaccines (TIVs), MF59-adjuvanted TIV (MF59-TIV), intradermal TIV (ID-TIV) and quadrivalent inactivated vaccines (QIVs). The present study is the first to compare the cost-effectiveness profiles of virtually all possible public health strategies, including the aforementioned four vaccine formulations as well non-vaccination. For this purpose, a decision tree model was built ex novo; the analysis was conducted from the third-payer perspective in the timeframe of one year. All available vaccines were cost-effective compared with non-vaccination. However, MF59-TIV had the most favorable economic profile in the Italian elderly population. Indeed, compared with non-vaccination, it was deemed highly cost-effective with an incremental cost-effectiveness ratio (ICER) of \u20ac10,750 per quality-adjusted life year (QALY). The ICER was much lower (\u20ac4,527/QALY) when MF59-TIV was directly compared with TIV. ID-TIV and QIV were dominated by MF59-TIV as the former comparators were associated with greater total costs and lower health benefits. Both deterministic and probabilistic sensitivity analyses confirmed robustness of the base case results. From the economic perspective, MF59-TIV should be considered as a preferential choice for Italian older adults aged 65&nbsp;years or above