Open AccessCommentary
A Tourism Financial Conditions Index for Tourism Finance
Challenges 2017, 8(2), 23; doi:10.3390/challe8020023 -
Abstract
The paper uses monthly data on tourism related factors from April 2005–June 2016 for Taiwan that applies factor analysis and Chang’s (2015) novel approach for constructing a tourism financial indicator, namely the Tourism Financial Conditions Index (TFCI). The TFCI is an adaptation and
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The paper uses monthly data on tourism related factors from April 2005–June 2016 for Taiwan that applies factor analysis and Chang’s (2015) novel approach for constructing a tourism financial indicator, namely the Tourism Financial Conditions Index (TFCI). The TFCI is an adaptation and extension of the widely-used Monetary Conditions Index (MCI) and Financial Conditions Index (FCI) to tourism stock data. However, the method of calculation of the TFCI is different from existing methods of constructing the MCI and FCI in that the weights are estimated empirically. The empirical findings show that TFCI is statistically significant using the estimated conditional mean of the tourism stock index returns (RTS). Granger Causality tests show that TFCI shows strong feedback on RTS. An interesting insight is that the empirical results show a significant negative correlation between F1_visitors (Foreign Visitor Arrivals) and RTS, implying that tourism authorities might promote travel by the “rich”, and not only on inbound visitor growth. The use of market returns on the tourism stock sub-index as the sole indicator of the tourism sector, as compared with the general activity of economic variables on tourism stocks, is shown to provide an exaggerated and excessively volatile explanation of tourism financial conditions. Full article
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Open AccessCommentary
Astrofood, Priorities and Pandemics: Reflections of an Ultra-Processed Breakfast Program and Contemporary Dysbiotic Drift
Challenges 2017, 8(2), 24; doi:10.3390/challe8020024 -
Abstract
Recognizing the importance of nutrition as part of the grand challenges faced by humanity—the current epidemic of non-communicable diseases (NCDs), sustainability and maintenance of Planetary Health—the United Nations (UN) has declared 2016–2025 the Decade of Nutrition. Research continues to underscore the extent to
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Recognizing the importance of nutrition as part of the grand challenges faced by humanity—the current epidemic of non-communicable diseases (NCDs), sustainability and maintenance of Planetary Health—the United Nations (UN) has declared 2016–2025 the Decade of Nutrition. Research continues to underscore the extent to which ultra-processed foods dominate the contemporary nutritional landscape. Moreover, the dual role played by food technology and marketing in the expansion of ultra-processed foods is under increased scrutiny. As public health experts and clinicians contend with a crisis of NCDs, attempting to untangle a knotted assortment of interrelated strands of causation, an examination of the early origins of highly-marketed ultra-processed foods can provide valuable lessons. Here, we illuminate a little-known piece of history in the annals of ultra-processed nutritional science and childhood welfare. Astrofood was a commercially-marketed, collaborative government-industry effort that brought soy protein-enriched Twinkies as a nutritive breakfast cake to disadvantaged children; its concept and delivery demonstrated an unwillingness to deal with root-cause challenges. Although its official tenure was only about 7 years, we argue that Astrofood and its total food engineering still resonate throughout the global ultra-processed nutritional landscape. New scientific advances in nutritional psychiatry and the microbiome are on a collision course with the profits, marketing and intellectual dishonesty of the ultra-processed food industry. Solutions to the grand challenges of the Decade of Nutrition may be found in lessons from Astrofood. They provide clues to undoing the tangled knots which otherwise maintain an untenable status quo. Full article
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Open AccessCommentary
The Challenge of the ‘Art and Science’ of Health Promotion
Challenges 2017, 8(2), 22; doi:10.3390/challe8020022 -
Abstract
Health promotion has a key role to play in preventing disease and promoting healthy lifestyles. Health promotion work is part science and part art. The science emerges from research and theory and the art emerges from our professional intuition and experience. The goal
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Health promotion has a key role to play in preventing disease and promoting healthy lifestyles. Health promotion work is part science and part art. The science emerges from research and theory and the art emerges from our professional intuition and experience. The goal is to apply the science to achieve the best health promotion outcomes. However, an application of the theory, models and even the evidence, does not guarantee a desired outcome. To achieve this is an art and something that is often missing in practice. An understanding of how best to apply the ‘art and science’ of health promotion requires an appreciation that it is not only about being scientifically right but also about being real. The challenge for health promoters is to understand how they can use their judgement to best apply the available science to deliver successful approaches. Full article
Open AccessFeature PaperArticle
Precision of a Streamlined Life Cycle Assessment Approach Used in Eco-Rating of Mobile Phones
Challenges 2017, 8(2), 21; doi:10.3390/challe8020021 -
Abstract
There is a lack of prescribed databases and approaches in place for performing comparable Life Cycle Assessments (LCAs) of smartphones and other electronic devices in a coherent manner. Hence there is a need within certain eco-rating initiatives for simplified, yet still precise enough,
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There is a lack of prescribed databases and approaches in place for performing comparable Life Cycle Assessments (LCAs) of smartphones and other electronic devices in a coherent manner. Hence there is a need within certain eco-rating initiatives for simplified, yet still precise enough, approaches that are expert independent. Here, five independently published Full LCAs (FLCA) of smartphones—and a metal content declaration of a tablet—are analyzed and compared with the simplified LCA method (Open Eco Rating LCA, OLCA) used by the open eco rating (OER) sustainability assessment. OLCA is described in detail. The comparisons use the same characterization factors that are used for climate change and abiotic resource depletion (ARD) midpoint impact categories. The tablet is only analyzed for the ARD indicator (ARDI). The results show that the difference between the FLCAs and the OLCA is up to 20% for the Global Warming Potential indicator (GWPI). The difference is explained by significantly different emission intensities used in FLCAs and OLCA, especially for integrated circuit and screen production. The life cycle use of metals relevant for ARDI is identified in one of the FLCAs of mobile phones, and used in OLCA and compared with the corresponding FLCA ARDI score. The total FLCA ARDI score is 67% (2.0 vs. 1.2 grams Sb—eq.) and 32% (4.98 vs. 3.76 grams Sb—eq.) higher than OLCA ARDI for the mobile phone and the tablet, respectively. The reason is that OLCA only captures a few of the most relevant metals (gold, silver, tin, indium, and tantalum) for the ARDI. However, cobalt—and to some degree copper and lithium—are significant gaps in the OLCA. The conclusion is that OLCA is an efficient and fair approach for LCAs that are focused on the GWPI of smartphones as the divergence to FLCA can easily be explained. However, the circular footprint formulae, renewable electricity options, and ARD characterization indices for cobalt, copper and lithium should be added to OLCA for further precision. The next step is to compare the Product Environmental Footprint (PEF) FLCA method with OLCA for GWPI and ARDI evaluations of new smartphones. Moreover, the effect of adding more midpoint or single score indicators could be tested in OLCA. Full article
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Open AccessCommunication
Unaffiliated Researchers: A Preliminary Study
Challenges 2017, 8(2), 20; doi:10.3390/challe8020020 -
Abstract
This paper aims to explore the apparently rising trend of unaffiliated researchers. It does so by analyzing a set of scholarly publications where the authors state “independent researcher” in place of their affiliation. Some of the characteristics of this set are explained along
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This paper aims to explore the apparently rising trend of unaffiliated researchers. It does so by analyzing a set of scholarly publications where the authors state “independent researcher” in place of their affiliation. Some of the characteristics of this set are explained along with directions on how to expand research on this topic. Full article
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Open AccessCommentary
Down to Earth: Planetary Health and Biophilosophy in the Symbiocene Epoch
Challenges 2017, 8(2), 19; doi:10.3390/challe8020019 -
Abstract
Advances in science have illuminated the role of the “ecological theatre”—the total living environment—in human health. In a rapidly changing epoch known as the anthropocene, microbiome science is identifying functional connections between all life, both seen and unseen. Rather than an easily identifiable
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Advances in science have illuminated the role of the “ecological theatre”—the total living environment—in human health. In a rapidly changing epoch known as the anthropocene, microbiome science is identifying functional connections between all life, both seen and unseen. Rather than an easily identifiable era appearing in rock strata, the anthropocene is more of a diagnostic syndrome, a set of signs and symptoms including climate change, gross biodiversity losses, environmental degradation, and an epidemic of non-communicable diseases. The syndrome is intertwined with politics, economics, public policies (or lack thereof), social values, and a global push of calorie-dense, nutrient-poor foods and beverages. The healing of anthropocene syndrome is the grand challenge of humanity. Expanding on the “Mars Can Wait” argument of Geoffrey Goodman, et al., we focus on the urgency with which health promotion must be prioritized here on Earth. We revive Jonas Salk’s biophilosophy: a call to action for collaboration between biologists, humanists, and scholars of all stripes. From this perspective, lines of distinction between personal, public, and planetary health are removed. We also describe the symbiocene: the possibility of a new epoch in which mutualism will be considered imperative. If society asks the right questions, a transition to the symbiocene is possible; the “stratigraphical” mark of the new epoch will be found in a repudiation of authoritarianism, and the promotion of empathy, cultural competency, emotional intelligence, and commitment to optimism, tolerance, and the facilitation of the WHO definition of health, i.e., the fulfillment of human potential. Full article
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Open AccessPerspective
The Lack of Alignment among Environmental Research Infrastructures May Impede Scientific Opportunities
Challenges 2017, 8(2), 18; doi:10.3390/challe8020018 -
Abstract
Faced with growing stakeholder attention to climate change-related societal impacts, Environmental Research Infrastructures (ERIs) find it difficult to engage beyond their initial user base, which calls for an overarching governance scheme and transnational synergies. Forced by the enormity of tackling climate change, ERIs
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Faced with growing stakeholder attention to climate change-related societal impacts, Environmental Research Infrastructures (ERIs) find it difficult to engage beyond their initial user base, which calls for an overarching governance scheme and transnational synergies. Forced by the enormity of tackling climate change, ERIs are indeed broaching collaborative venues, based on the assumption that no given institution can carry out this agenda alone. While strategic, this requires that ERIs address the complexities and barriers towards aligning multiple organizations, national resources and programmatic cultures, including science. Full article
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Open AccessShort Note
Globalization, Inequality, Say’s Law, and Fiscal Globalism
Challenges 2017, 8(2), 17; doi:10.3390/challe8020017 -
Abstract
This is a brief note maintaining that financial globalization has been faster than the integration of the remaining sectors of the world economy, thus encouraging wealth inequality, under-production, and under-consumption in line with Say’s Law. Financial investment has become more profitable than real
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This is a brief note maintaining that financial globalization has been faster than the integration of the remaining sectors of the world economy, thus encouraging wealth inequality, under-production, and under-consumption in line with Say’s Law. Financial investment has become more profitable than real investment, discouraging production ventures, and weakening labor’s relative income position and purchasing power. Moreover, this article works out a model of international government indirect tax competition as a policy means against increasing inequality. The mentality under which this tax policy paradigm is put forward is that the competition of nation states in a fiscal globalism fashion crystallizes the optimal level of centralization under globalism; optimal, that is, from the viewpoint of safeguarding against the manipulation of world markets by financiers. Full article
Open AccessBook Review
Embryogenesis Explained. By Natalie K. Gordon and Richard Gordon. World Scientific: Hackensack, NJ, USA, 2016; 784 pp.; SGD 281; ISBN: 978-981-4350-48-8
Challenges 2017, 8(2), 16; doi:10.3390/challe8020016 -
Open AccessCommunication
Life Cycle Assessment of a Virtual Reality Device
Challenges 2017, 8(2), 15; doi:10.3390/challe8020015 -
Abstract
Virtual reality (VR) is one of the strongest trends for future communication systems. Considering the amounts of VR devices expected to be produced in the coming years, it is relevant to estimate their potential environmental impacts under certain conditions. For the first time,
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Virtual reality (VR) is one of the strongest trends for future communication systems. Considering the amounts of VR devices expected to be produced in the coming years, it is relevant to estimate their potential environmental impacts under certain conditions. For the first time, screening life cycle assessment (LCA) single score results are presented for a contemporary VR headset. The weighted results are dependent much on the source of the gold and the electric power used in production. Theoretically, using recycled gold for the VR subparts would be very beneficial seen from an environmental damage cost standpoint. Using low environmental impact electric power in the final assembly of the VR headset, in the final assembly of integrated circuits, and in the preceding wafer processing would also be worthwhile. Distribution of the final product is more pronounced than for other consumer electronics. Full article
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Open AccessEditorial
ADP-Ribosylation Reactions in Animals, Plants, and Bacteria
Challenges 2017, 8(1), 14; doi:10.3390/challe8010014 -
Open AccessReview
Hydrogen Storage Technologies for Smart Grid Applications
Challenges 2017, 8(1), 13; doi:10.3390/challe8010013 -
Abstract
The electricity sector is among the main contributors to carbon emissions. This sector has the potential to reduce its carbon emissions through producing electric energy from zero-emitting facilities and optimizing consumption to better accommodate low-carbon emissions. The use of hydrogen combined with smart
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The electricity sector is among the main contributors to carbon emissions. This sector has the potential to reduce its carbon emissions through producing electric energy from zero-emitting facilities and optimizing consumption to better accommodate low-carbon emissions. The use of hydrogen combined with smart grids, as analyzed in this manuscript, can substantially contribute to climate change mitigation. Full article
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Open AccessProject Report
Ethics and the Potential Conflicts between Astrobiology, Planetary Protection, and Commercial Use of Space
Challenges 2017, 8(1), 12; doi:10.3390/challe8010012 -
Abstract
A high standard of planetary protection is important for astrobiology, though the risk for contamination can never be zero. It is therefore important to find a balance. If extraterrestrial life has a moral standing in its own right, it will also affect what
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A high standard of planetary protection is important for astrobiology, though the risk for contamination can never be zero. It is therefore important to find a balance. If extraterrestrial life has a moral standing in its own right, it will also affect what we have to do to protect it. The questions of how far we need to go to protect extraterrestrial life will be even more acute and complicated when the time comes to use habitable worlds for commercial purposes. There will also be conflicts between those who want to set a world aside for more research and those who want to give the green light for development. I believe it is important to be proactive in relation to these issues. The aim of my project is therefore to identify, elucidate, and if possible, suggest solutions to potential conflicts between astrobiology, planetary protection, and commercial use of space. Full article
Open AccessArticle
About the Purification Route of Ionic Liquid Precursors
Challenges 2017, 8(1), 11; doi:10.3390/challe8010011 -
Abstract
In this work a purification route of precursors for ionic liquids tailored to electrochemical energy storage systems is reported and described. The study was carried out on the N-butyl-N-methylpyrrolidinium bromide (PYR14Br) precursor, which represents the intermediate product of
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In this work a purification route of precursors for ionic liquids tailored to electrochemical energy storage systems is reported and described. The study was carried out on the N-butyl-N-methylpyrrolidinium bromide (PYR14Br) precursor, which represents the intermediate product of the synthesis process of the N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR14TFSI) hydrophobic ionic liquid. The target is to develop an easy and cost-effective approach for efficiently purifying several kinds of ionic liquid precursors and determining their purity content. The PYR14Br precursor was synthesized through an eco-friendly preparation procedure, which requires water as the only processing solvent, and purified through sorbent materials, such as activated charcoal and alumina. The effect of the treatment/nature/content of sorbents and processing temperature/time was investigated. The impurity content was detected by UV-VIS spectrophotometry measurements. Additionally, a correlation between the measured absorbance and the content of impurities within the precursor was obtained. The purity level of the precursor was seen to play a key role in the electrochemical performance of the ionic liquids. Full article
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Open AccessArticle
Electrochemical Sensor for Explosives Precursors’ Detection in Water
Challenges 2017, 8(1), 10; doi:10.3390/challe8010010 -
Abstract
Although all countries are intensifying their efforts against terrorism and increasing their mutual cooperation, terrorist bombing is still one of the greatest threats to society. The discovery of hidden bomb factories is of primary importance in the prevention of terrorism activities. Criminals preparing
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Although all countries are intensifying their efforts against terrorism and increasing their mutual cooperation, terrorist bombing is still one of the greatest threats to society. The discovery of hidden bomb factories is of primary importance in the prevention of terrorism activities. Criminals preparing improvised explosives (IE) use chemical substances called precursors. These compounds are released in the air and in the waste water during IE production. Tracking sources of precursors by analyzing air or wastewater can then be an important clue for bomb factories’ localization. We are reporting here a new multiplex electrochemical sensor dedicated to the on-site simultaneous detection of three explosive precursors, potentially used for improvised explosive device preparation (hereafter referenced as B01, B08, and B15, for security disclosure reasons and to avoid being detrimental to the security of the counter-explosive EU action). The electrochemical sensors were designed to be disposable and to combine ease of use and portability in a screen-printed eight-electrochemical cell array format. The working electrodes were modified with different electrodeposited metals: gold, palladium, and platinum. These different coatings giving selectivity to the multi-sensor through a “fingerprint”-like signal subsequently analyzed using partial least squares-discriminant analysis (PLS-DA). Results are given regarding the detection of the three compounds in a real environment and in the presence of potentially interfering species. Full article
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Open AccessArticle
Case Studies of Energy Storage with Fuel Cells and Batteries for Stationary and Mobile Applications
Challenges 2017, 8(1), 9; doi:10.3390/challe8010009 -
Abstract
In this paper, hydrogen coupled with fuel cells and lithium-ion batteries are considered as alternative energy storage methods. Their application on a stationary system (i.e., energy storage for a family house) and a mobile system (i.e., an unmanned aerial vehicle) will be investigated.
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In this paper, hydrogen coupled with fuel cells and lithium-ion batteries are considered as alternative energy storage methods. Their application on a stationary system (i.e., energy storage for a family house) and a mobile system (i.e., an unmanned aerial vehicle) will be investigated. The stationary systems, designed for off-grid applications, were sized for photovoltaic energy production in the area of Turin, Italy, to provide daily energy of 10.25 kWh. The mobile systems, to be used for high crane inspection, were sized to have a flying range of 120 min, one being equipped with a Li-ion battery and the other with a proton-exchange membrane fuel cell. The systems were compared from an economical point of view and a life cycle assessment was performed to identify the main contributors to the environmental impact. From a commercial point of view, the fuel cell and the electrolyzer, being niche products, result in being more expensive with respect to the Li-ion batteries. On the other hand, the life cycle assessment (LCA) results show the lower burdens of both technologies. Full article
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Open AccessReview
Hydrides as High Capacity Anodes in Lithium Cells: An Italian “Futuro in Ricerca di Base FIRB-2010” Project
Challenges 2017, 8(1), 8; doi:10.3390/challe8010008 -
Abstract
Automotive and stationary energy storage are among the most recently-proposed and still unfulfilled applications for lithium ion devices. Higher energy, power and superior safety standards, well beyond the present state of the art, are actually required to extend the Li-ion battery market to
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Automotive and stationary energy storage are among the most recently-proposed and still unfulfilled applications for lithium ion devices. Higher energy, power and superior safety standards, well beyond the present state of the art, are actually required to extend the Li-ion battery market to these challenging fields, but such a goal can only be achieved by the development of new materials with improved performances. Focusing on the negative electrode materials, alloying and conversion chemistries have been widely explored in the last decade to circumvent the main weakness of the intercalation processes: the limitation in capacity to one or at most two lithium atoms per host formula unit. Among all of the many proposed conversion chemistries, hydrides have been proposed and investigated since 2008. In lithium cells, these materials undergo a conversion reaction that gives metallic nanoparticles surrounded by an amorphous matrix of LiH. Among all of the reported conversion materials, hydrides have outstanding theoretical properties and have been only marginally explored, thus making this class of materials an interesting playground for both fundamental and applied research. In this review, we illustrate the most relevant results achieved in the frame of the Italian National Research Project FIRB 2010 Futuro in Ricerca “Hydrides as high capacity anodes in lithium cells” and possible future perspectives of research for this class of materials in electrochemical energy storage devices. Full article
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Open AccessArticle
A Study of the Conformers of the (Nonafluorobutanesulfonyl)imide Ion by Means of Infrared Spectroscopy and Density Functional Theory (DFT) Calculations
Challenges 2017, 8(1), 7; doi:10.3390/challe8010007 -
Abstract
Pyrrolidinium-based ionic liquids with anions of the per(fluoroalkylsulfonyl)imide family are particularly interesting for their use as electrolytes in lithium batteries. These ions have several geometric isomers and the presence of different ion conformers and their distribution affects the ILs (Ionic liquids) physical and
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Pyrrolidinium-based ionic liquids with anions of the per(fluoroalkylsulfonyl)imide family are particularly interesting for their use as electrolytes in lithium batteries. These ions have several geometric isomers and the presence of different ion conformers and their distribution affects the ILs (Ionic liquids) physical and chemical properties. In the present work, we report the temperature dependence of the infrared spectra of the N-butyl-N-methyl-pyrrolidinium(trifluoromethanesulfonyl)(nonafluorobutanesulfonyl)imide (PYR14IM14) ionic liquid; DFT (Density Functional Theory) calculations performed with different models provides indications about the IM14 conformers and their vibrational spectra. Moreover the temperature dependence of the intensity of the lines identified as markers of different conformers provide indications about the conformers’ distribution and the difference of their enthalpy in the liquid phase. Full article
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Open AccessArticle
Tie-Up Cycles in Long-Term Mating. Part II: Fictional Narratives and the Social Cognition of Mating
Challenges 2017, 8(1), 6; doi:10.3390/challe8010006 -
Abstract
In the first part of this paper, we have introduced a novel theoretical approach to mating dynamics, known as Tie-Up Theory (TU). In this second part, in the context of the bio-cultural approach to literature, that assigns to fictional narratives an important valence
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In the first part of this paper, we have introduced a novel theoretical approach to mating dynamics, known as Tie-Up Theory (TU). In this second part, in the context of the bio-cultural approach to literature, that assigns to fictional narratives an important valence of social cognition, we apply the conceptual tools presented in the first part to the analysis of mating-related interaction dynamics in some blockbuster Hollywood movies from WWII to today. The interaction dynamics envisioned by our theory accurately reflect, to a significant level of detail, the narrative development of the movies under exam from the viewpoint of the mating dynamics of the couple of main characters, accounting for the specific reasons that lead them to react to certain situations via certain behaviors, and for the reasons why such behaviors lead to certain outcomes. Our analysis seems thus to bring some further legitimacy to the bio-cultural foundation of the narrative structure of the movies that we analyze, and moreover to the idea that it is possible to ‘inquire’ characters about their choices according to the narratological-experimental lines suggested by some proponents of the bio-cultural approach. Full article
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Open AccessArticle
Ionic Mobility and Phase Transitions in Perovskite Oxides for Energy Application
Challenges 2017, 8(1), 5; doi:10.3390/challe8010005 -
Abstract
Perovskite oxides find applications or are studied in many fields related to energy production, accumulation and saving. The most obvious application is oxygen or proton conductors in fuel cells (SOFCs), but the (anti)ferroelectric compositions may find application in high energy capacitors for energy
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Perovskite oxides find applications or are studied in many fields related to energy production, accumulation and saving. The most obvious application is oxygen or proton conductors in fuel cells (SOFCs), but the (anti)ferroelectric compositions may find application in high energy capacitors for energy storage, efficient electrocaloric cooling, and electromechanical energy harvesting. In SOFCs, the diffusion of O vacancies and other mobile ionic species, such as H+, are at the base of the functioning of the device, while in the other cases they constitute unwanted defects that reduce the performance and life-time of the device. Similarly, the (anti)ferroelectric phase transitions are a requisite for the use of some types of devices, but the accompanying domain walls can generate extended defects detrimental to the life of the material, and structural phase transformations should be avoided in SOFCs. All these phenomena can be studied by mechanical spectroscopy, the measurement of the complex elastic compliance as a function of temperature and frequency, which is the mechanical analogue of the dielectric susceptibility, but probes the elastic response and elastic dipoles instead of the dielectric response and electric dipoles. The two techniques can be combined to provide a comprehensive picture of the material properties. Examples are shown of the study of structural transitions and hopping and tunnelling processes of O vacancies and H in the ion conductor BaCe1-xYxO3-x and in SrTiO3-x, and of the aging and fatigue effects found in PZT at compositions where the ferro- and antiferroelectric states coexist. Full article
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