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Challenges, Volume 7, Issue 1 (June 2016) – 13 articles

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2617 KiB  
Article
Potential for Reuse of E-Plastics through Processing by Compression Molding
by William Mills and Robert A. Tatara
Challenges 2016, 7(1), 13; https://doi.org/10.3390/challe7010013 - 19 May 2016
Cited by 5 | Viewed by 5574
Abstract
The amounts of e-waste, consisting of metal (e-metals) and plastic (e-plastics) streams from electronic goods, are increasing in the United States and elsewhere. The e-metals waste streams are being recycled to a reasonable degree due to the value of precious metals. E-plastic waste [...] Read more.
The amounts of e-waste, consisting of metal (e-metals) and plastic (e-plastics) streams from electronic goods, are increasing in the United States and elsewhere. The e-metals waste streams are being recycled to a reasonable degree due to the value of precious metals. E-plastic waste streams currently are not recycled or reused to a significant extent. As a result, most e-plastics are disposed of by landfilling or thermal treatment, or sent overseas for alleged recycling or reuse, any of which could result in unsafe worker exposure and release into the environment. Two of the major barriers to e-plastics’ reuse or recycling are the mixed plastic content and the presence in the e-plastics of flame retardants (FR), of which two classes in particular, the brominated flame retardants (BFR) and organo-phosphorus flame retardants (OPFR), have associated health concerns. The major goal of this project is to investigate the possibility of direct reuse of e-plastics in compression molding. Preliminary data generated have identified a molding procedure that yields remanufactured e-plastics having a tensile strength of 29.3 MPa. This moderate strength level is suspected to be due to inclusions of plastic bits that did not melt and internal voids from out-gassing. Handheld X-ray fluorescence (XRF) was utilized to characterize elemental components in the e-plastics tested for compression molding. Several high “hits” for Br were found that could not be predicted visually. The preliminary XRF data for BFR and OPFR in this work are helpful for environmental and occupational hazard assessments of compression molding activities. Additionally, methods are suggested to characterize the metals, BFR, and OPFR content of the e-plastics using several different additional laboratory analytical techniques to determine the suitability for cost-effective and easy-to-use technologies. Full article
(This article belongs to the Special Issue Electronic Waste — Impact, Policy and Green Design)
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4024 KiB  
Article
Tie-Up Cycles in Long-Term Mating. Part I: Theory
by Lorenza Lucchi Basili and Pier Luigi Sacco
Challenges 2016, 7(1), 12; https://doi.org/10.3390/challe7010012 - 03 May 2016
Cited by 6 | Viewed by 7342
Abstract
In this paper, we propose a new approach to couple formation and dynamics that abridges findings from sexual strategies theory and attachment theory to develop a framework where the sexual and emotional aspects of mating are considered in their strategic interaction. Our approach [...] Read more.
In this paper, we propose a new approach to couple formation and dynamics that abridges findings from sexual strategies theory and attachment theory to develop a framework where the sexual and emotional aspects of mating are considered in their strategic interaction. Our approach presents several testable implications, some of which find interesting correspondences in the existing literature. Our main result is that, according to our approach, there are six typical dynamic interaction patterns that are more or less conducive to the formation of a stable couple, and that set out an interesting typology for the analysis of real (as well as fictional, as we will see in the second part of the paper) mating behaviors and dynamics. Full article
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147 KiB  
Opinion
Alternative Energies and Fossil Fuels in the Bioeconomy Era: What is Needed in the Next Five Years for Real Change
by Palmiro Poltronieri
Challenges 2016, 7(1), 11; https://doi.org/10.3390/challe7010011 - 18 Apr 2016
Cited by 3 | Viewed by 3605
Abstract
Sustainable biomass feedstock is the key to sustainable biofuels.[...] Full article
3136 KiB  
Article
Modeling Autonomous Decision-Making on Energy and Environmental Management Using Petri-Net: The Case Study of a Community in Bandung, Indonesia
by Niken Prilandita, Benjamin McLellan and Tetsuo Tezuka
Challenges 2016, 7(1), 9; https://doi.org/10.3390/challe7010009 - 14 Apr 2016
Cited by 3 | Viewed by 8206
Abstract
Autonomous decision-making in this study is defined as the process where decision-makers have the freedom and ability to find problems, select goals, and make decisions for achieving the selected problems/goals by themselves. Autonomous behavior is considered significant for achieving decision implementation, especially in [...] Read more.
Autonomous decision-making in this study is defined as the process where decision-makers have the freedom and ability to find problems, select goals, and make decisions for achieving the selected problems/goals by themselves. Autonomous behavior is considered significant for achieving decision implementation, especially in the context of energy and environmental management, where multiple stakeholders are involved and each stakeholder holds valuable local information for making decisions. This paper aims to build a structured process in modeling the autonomous decision-making. A practical decision-making process in waste-to-energy conversion activities in a community in Bandung, Indonesia, is selected as a case study. The decision-making process here is considered as a discrete event system, which is then represented as a Petri-net model. First, the decision-making process in the case study is decomposed into discrete events or decision-making stages, and the stakeholders’ properties in each stage are extracted from the case study. Second, several stakeholder properties that indicate autonomous behavior are identified as autonomous properties. Third, presented is a method to develop the decision-making process as a Petri-net model. The model is utilized for identifying the critical points for verifying the performance of the derived Petri-net. Full article
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1078 KiB  
Opinion
Flaws and Drawbacks in Present Regulation and the Need to Take Action and Support the Renewable Energies Policies in Italy
by Valeria Mezzolla
Challenges 2016, 7(1), 10; https://doi.org/10.3390/challe7010010 - 14 Apr 2016
Viewed by 3054
Abstract
Renewable energies is an important sector that needs to be sustained and increased by the action of policies and economic support.[...] Full article
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132 KiB  
Letter
Policies Supporting Renewable Energies Uses: The Next Big Challenge
by Ferdinando Boero
Challenges 2016, 7(1), 8; https://doi.org/10.3390/challe7010008 - 11 Apr 2016
Viewed by 2832
Abstract
The question in the referendum on 17 April is: “At the end of the concessions presently authorized for extraction plants in the sea, at a distance within 12 km from the coast of Italy, are you in favor of stopping the extraction, even [...] Read more.
The question in the referendum on 17 April is: “At the end of the concessions presently authorized for extraction plants in the sea, at a distance within 12 km from the coast of Italy, are you in favor of stopping the extraction, even if there is still some methane or oil to be extracted?”.[...] Full article
147 KiB  
Opinion
Fossil Fuels, Let’s Leave Them under Earth. Four Reasons to Vote “Yes” at the Italian Referendum on Drilling
by ASPO Italy Association for the Study of PeakOil And Gas
Challenges 2016, 7(1), 7; https://doi.org/10.3390/challe7010007 - 08 Apr 2016
Cited by 1 | Viewed by 2830
Abstract
The referendum that will be held on 17 April 2016 is calling Italians to express their willingness on an aspect of licensing the sea drilling activities: The end of the licenses to the offshore exploitation of fossil fuel resources within the 12 miles [...] Read more.
The referendum that will be held on 17 April 2016 is calling Italians to express their willingness on an aspect of licensing the sea drilling activities: The end of the licenses to the offshore exploitation of fossil fuel resources within the 12 miles from the coast. Full article
146 KiB  
Editorial
On Energy Resources, Climate Change, Fossil Fuels, and Drilling. Challenges in Tackling Problems by Governments in Europe and USA
by Palmiro Poltronieri
Challenges 2016, 7(1), 6; https://doi.org/10.3390/challe7010006 - 01 Apr 2016
Viewed by 3343
Abstract
This month in Italy a public consultation will decide (by majority, in case 50% of voters will participate) whether to renew the ongoing concessions between Italian government and drilling companies at the end of their contracts, even if the fossil fuels have not [...] Read more.
This month in Italy a public consultation will decide (by majority, in case 50% of voters will participate) whether to renew the ongoing concessions between Italian government and drilling companies at the end of their contracts, even if the fossil fuels have not been extracted completely.[...] Full article
2379 KiB  
Article
Bridging the Gap between Eco-Design and the Human Thinking System
by Mona Komeijani, Erinn G. Ryen and Callie W. Babbitt
Challenges 2016, 7(1), 5; https://doi.org/10.3390/challe7010005 - 10 Mar 2016
Cited by 4 | Viewed by 6852
Abstract
Technological progress has enabled widespread adoption and use of consumer electronics, changing how global society lives and works. This progress has come with immense environmental cost, including extraction of scarce materials, consumption of fossil fuels, and growing e-waste challenges. Eco-design has emerged as [...] Read more.
Technological progress has enabled widespread adoption and use of consumer electronics, changing how global society lives and works. This progress has come with immense environmental cost, including extraction of scarce materials, consumption of fossil fuels, and growing e-waste challenges. Eco-design has emerged as a promising approach to reduce the environmental footprint of electronics by integrating sustainability-oriented decisions early in the product realization process. However, most approaches focus on the product itself, not on the consumer who ultimately decides how to purchase, use, maintain, and dispose of the device. This article presents a new framework to guide designers in developing products with features that encourage consumers to use them in an environmentally sustainable manner. The Sustainable Behavior Design (SBD) framework links common design concepts (ergonomic, emotional, preventative, and interaction design) with core aspects of the human thinking system to create features to make users aware of their behavior and decisions (reflective thinking) or result in sustainable behaviors even when users are unaware (automatic thinking). The SBD framework is demonstrated using a case study on a smartphone, a high demand product. The reimagined smartphone design integrates solutions addressing both automatic and reflective thinking systems, potentially reducing life cycle impacts by almost 30%. Full article
(This article belongs to the Special Issue Electronic Waste — Impact, Policy and Green Design)
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1530 KiB  
Article
Practical Eco-Design and Eco-Innovation of Consumer Electronics—the Case of Mobile Phones
by Anders S. G. Andrae, Mengjun Xia, Jianli Zhang and Xiaoming Tang
Challenges 2016, 7(1), 3; https://doi.org/10.3390/challe7010003 - 15 Feb 2016
Cited by 19 | Viewed by 9232
Abstract
Annually, it is estimated that about 4 billion units of consumer electronics for mobile communications are produced worldwide. This could lead to various ecological imbalances unless the design and disposal of the products are handled optimally. To illustrate how industry looks at and [...] Read more.
Annually, it is estimated that about 4 billion units of consumer electronics for mobile communications are produced worldwide. This could lead to various ecological imbalances unless the design and disposal of the products are handled optimally. To illustrate how industry looks at and responds to the increasing social awareness, this article describes how sustainability is successfully implemented in practice at a large Chinese company, developing and producing various kinds of electronic products used for communication. It also describes how a variety of eco-innovations and business models contribute to reducing the environmental impact; for example, through increased recovery and recycling. A new kind of eco-design procedure is presented along with a new methodology which shows how a mobile phone gradually becomes more sustainable from one generation to the next. The issues with and set-up of new eco-labeling schemes for mobile phones, eco-rating, is described in detail. The conclusion is that due to high competition between companies, the industry acts resourcefully and a lot is done to the save the ecological environment. Full article
(This article belongs to the Special Issue Electronic Waste — Impact, Policy and Green Design)
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1842 KiB  
Brief Report
Use of Bacteriocinogenic Cultures without Inhibiting Cheese Associated Nonstarter Lactic Acid Bacteria; A Trial with Lactobacillus plantarum
by Franca Rossi and Gianluca Veneri
Challenges 2016, 7(1), 4; https://doi.org/10.3390/challe7010004 - 14 Feb 2016
Cited by 3 | Viewed by 4881
Abstract
Bacteriocinogenic cultures can represent a natural way to increase the safety of cheeses made from raw milk, in which a relevant role in ripening and flavor formation is exerted by the nonstarter lactic acid bacteria (NSLAB). Since the latter can be inhibited by [...] Read more.
Bacteriocinogenic cultures can represent a natural way to increase the safety of cheeses made from raw milk, in which a relevant role in ripening and flavor formation is exerted by the nonstarter lactic acid bacteria (NSLAB). Since the latter can be inhibited by bacteriocin producers, this study evaluated to which extent a nisinogenic culture inoculated at low initial levels can affect the growth rate and peptide degradation activity of the nisin-sensitive cheese isolate Lactobacillus plantarum LZ by comparison with its isogenic variant, L. plantarum LZNI, with increased immunity to nisin. A growth delay of the nisin sensitive strain was observed only when its initial number was 100-fold lower than the nisin producer and nisin was added as an inducer of its own production. In this case, the amount of free α-amino groups was significantly different between cultures of L. plantarum LZ and LZNI only at Day 1. Reverse Phase High Performance Liquid Chromatography (RP-HPLC) highlighted a few differences between the peptide profiles of co-cultures L. plantarum LZ and LZNI. However, results showed that the bacteriocin producer did not dramatically influence the behavior of the sensitive NSLAB and that the evaluation of the effects on microbial contaminants in cheese is worthwhile. Full article
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519 KiB  
Review
Challenges in Creating Evidence in Environmental Health Risk Assessments: The Example of Second-Hand Smoke
by Florian Fischer
Challenges 2016, 7(1), 2; https://doi.org/10.3390/challe7010002 - 30 Jan 2016
Cited by 1 | Viewed by 4479
Abstract
Public health interventions are directed to influence the (state of a) risk factor, either by behavioral or environmental changes. Therefore, environmental health risk assessments are highly relevant for public health decision making and policy development. The credibility of an environmental health risk assessment [...] Read more.
Public health interventions are directed to influence the (state of a) risk factor, either by behavioral or environmental changes. Therefore, environmental health risk assessments are highly relevant for public health decision making and policy development. The credibility of an environmental health risk assessment depends, to a large extent, on the strength of the scientific evidence on which it is based. In this article, the main challenges for assessing the impact of a potential adverse health effect from an environmental pollutant are described. Second-hand smoke (SHS) was chosen to illustrate the current state of evidence. The assessment of the impact of potential adverse health effects from environmental risk factors is dependent on several issues, such as the hypothesized health outcome, the nature of the exposure, the dose-response-relationship and the variability and susceptibility of the exposed population. The example of SHS exposure highlights the need for evidence-based public health. Several challenges in terms of study design, assessment methods, as well as data analysis and synthesis with respect to the stratification of results, and consideration of bias and confounding exist. Future research needs to take into account which methods and techniques will be used to generate evidence for population-level decisions. Full article
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295 KiB  
Editorial
Acknowledgement to Reviewers of Challenges in 2015
by Challenges Editorial Office
Challenges 2016, 7(1), 1; https://doi.org/10.3390/challe7010001 - 25 Jan 2016
Cited by 2 | Viewed by 3114
Abstract
The editors of Challenges would like to express their sincere gratitude to the following reviewers for assessing manuscripts in 2015. [...] Full article
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