| 1. |
- Engquist, Björn, et al.
(författare)
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Stable and entropy satisfying approximations for transonic flow calculations
- 1980
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Ingår i: Mathematics of Computation. - 0025-5718 .- 1088-6842. ; 34:149, s. 45-75
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Tidskriftsartikel (refereegranskat)abstract
- Finite difference approximations for the small disturbance equation of transonic flow are developed and analyzed. New schemes of the Cole-Murman type are presented fpr which nonlinear stability is proved. The Cole-Murman scheme may have entropy violating expansion shocks as solutions. In the new schemes the switch between the subsonic and supersonic domains is designed such that these nonphysical shocks are guaranteed not to occur. Results from numercial calculations are given which illustrate these conclusions
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| 2. |
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| 3. |
- Laurenti, Rafael, 1980-, et al.
(författare)
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Measuring the Environmental Footprint of Leather Processing Technologies
- 2017
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Ingår i: Journal of Industrial Ecology. - : Blackwell Publishing. - 1088-1980 .- 1530-9290. ; 21:5, s. 1180-1187
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Tidskriftsartikel (refereegranskat)abstract
- The selection of materials and manufacturing processes often determines most of the environmental impact that a product will have during its life cycle. In directing consumption toward products with the least impact on the environment, measuring and comparing material alternatives with site-specific data is a fundamental prerequisite. Within the apparel and footwear industry, some famous brands have recently been basing their advertising on the claim that vegetable-tanned leather is more environmentally friendly than chromiumtanned leather. However, there is a lack of scientific research assessing and comparing vegetable-and chromium-tanned leather in a wider context than the toxicity of chromium. To fill this gap, this study measured and compared the carbon, water, and energy footprint of vegetable and chromium leather processing technology and intermediate processing stages in 12 selected tanneries in seven different countries worldwide. Each tannery proved to be very individual, and therefore attempting to perform this type of analysis without simply producing meaningless generalities is a challenge for companies, researchers, and regulators. The variability in results demonstrates that secondary data for the tanning phase should be utilized with caution in a decision-making context. The use of primary data would be advisable for life cycle assessment studies of leather goods. No significant differences were found in the footprint of vegetable and chromium leather processes, but these are only indicative findings and need confirmation in further studies. An important area needing investigation is then how a fair comparison can be made between renewable natural materials and nonrenewable materials used in both leather-processing technologies.
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| 4. |
- Magnusson, Thomas, 1970-, et al.
(författare)
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Industrial ecology and the boundaries of the manufacturing firm
- 2019
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Ingår i: Journal of Industrial Ecology. - : Wiley-Blackwell Publishing Inc.. - 1088-1980 .- 1530-9290. ; 23:5, s. 1211-1225
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Tidskriftsartikel (refereegranskat)abstract
- Decisions on organizational boundaries are critical aspects of manufacturing firms’ business strategies. This article brings together concepts and findings from industrial ecology and business strategy in order to understand how manufacturing firms engage in initiatives to facilitate recycling of process wastes. Based on a distinction between waste recovery and use of the recovered resources, the article introduces a typology of four different strategies: Closed, Outsourcing, Diversification, and Open. Each strategy has a unique set of organizational boundaries and is associated with different motives and benefits for the manufacturing firm. The typology of strategies provides a conceptual contribution to assist industrial managers in strategic decision-making, and to support further studies on organizational boundaries in industrial ecology research.
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| 5. |
- Sorooshian, Shahryar, 1980, et al.
(författare)
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Demotivating factors affecting the implementation of ISO 14001:2015 in Malaysia
- 2019
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Ingår i: Environmental Quality Management. - : Wiley. - 1088-1913 .- 1520-6483. ; 29:2, s. 85-95
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Tidskriftsartikel (refereegranskat)abstract
- © 2019 Wiley Periodicals, Inc. Industrialization has brought with it environmental problems and the consequences of pollution, which has been affecting the world for decades. Immediate action is required to raise industry's awareness of its social responsibilities toward the environment. However, experience shows that companies that have obtained International Organization of Standardization (ISO) 14001:2015 certifications in Malaysia occupy but a small niche among the country's businesses. The purpose of this study is to assess the list of barriers and challenges to implementing and obtaining certifications under the ISO 14001:2015 Environmental Management System (EMS) by Malaysian firms. In addition, this study will rank these factors relative to their importance. This study is aimed at EMS experts at the Scientific and Industrial Research Institute of Malaysia (SIRIM QAS International Sdn. Bhd.). The study uses mathematical pairwise comparisons to generate the list of critical challenges and barriers. Therefore, the study is expected to raise environmental awareness among Malaysia's industries regarding the adoption of ISO 14001:2015 standards. Furthermore, the study provides a guideline for Malaysia's industries and policy-makers to provide them with a better understanding of the barriers and challenges that companies face in implementing ISO 14001:2015 EMS, and at the same time, help them understand the need to eliminate the difficulties of standard implementation.
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| 6. |
- Brasco, Lorenzo, et al.
(författare)
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Uniqueness of extremals for some sharp Poincaré-Sobolev constants
- 2023
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Ingår i: Transactions of the American Mathematical Society. - : American Mathematical Society (AMS). - 0002-9947 .- 1088-6850. ; 376:5, s. 3541-3584
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Tidskriftsartikel (refereegranskat)abstract
- We study the sharp constant for the embedding of W01,p(Ω) into Lq(Ω), in the case 2 < p < q. We prove that for smooth connected sets, when q > p and q is sufficiently close to p, extremal functions attaining the sharp constant are unique, up to a multiplicative constant. This in turn gives the uniqueness of solutions with minimal energy to the Lane-Emden equation, with super-homogeneous right-hand side. The result is achieved by suitably adapting a linearization argument due to C.-S. Lin. We rely on some fine estimates for solutions of p−Laplace–type equations by L. Damascelli and B. Sciunzi.
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| 7. |
- Mármol-Sánchez, Emilio, et al.
(författare)
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Historical RNA expression profiles from the extinct Tasmanian tiger
- 2023
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Ingår i: Genome Research. - 1088-9051 .- 1549-5469. ; 33:8, s. 1299-1316
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Tidskriftsartikel (refereegranskat)abstract
- Paleogenomics continues to yield valuable insights into the evolution, population dynamics, and ecology of our ancestors and other extinct species. However, DNA sequencing cannot reveal tissue-specific gene expression, cellular identity, or gene regulation, which are only attainable at the transcriptional level. Pioneering studies have shown that useful RNA can be extracted from ancient specimens preserved in permafrost and historical skins from extant canids, but no attempts have been made so far on extinct species. We extract, sequence, and analyze historical RNA from muscle and skin tissue of a ∼130-year-old Tasmanian tiger (Thylacinus cynocephalus) preserved in desiccation at room temperature in a museum collection. The transcriptional profiles closely resemble those of extant species, revealing specific anatomical features such as slow muscle fibers or blood infiltration. Metatranscriptomic analysis, RNA damage, tissue-specific RNA profiles, and expression hotspots genome-wide further confirm the thylacine origin of the sequences. RNA sequences are used to improve protein-coding and noncoding annotations, evidencing missing exonic loci and the location of ribosomal RNA genes while increasing the number of annotated thylacine microRNAs from 62 to 325. We discover a thylacine-specific microRNA isoform that could not have been confirmed without RNA evidence. Finally, we detect traces of RNA viruses, suggesting the possibility of profiling viral evolution. Our results represent the first successful attempt to obtain transcriptional profiles from an extinct animal species, providing thought-to-be-lost information on gene expression dynamics. These findings hold promising implications for the study of RNA molecules across the vast collections of natural history museums and from well-preserved permafrost remains.
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| 8. |
- Vogan, Aaron A., et al.
(författare)
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The Enterprise, a massive transposon carrying Spok meiotic drive genes
- 2021
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Ingår i: Genome Research. - : Cold Spring Harbor Laboratory Press (CSHL). - 1088-9051 .- 1549-5469. ; 31:5, s. 789-798
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Tidskriftsartikel (refereegranskat)abstract
- The genomes of eukaryotes are full of parasitic sequences known as transposable elements (TEs). Most TEs studied to date are relatively small (50 — 12000 bp), but can contribute to very large proportions of genomes. Here we report the discovery of a giant tyrosine-recombinase-mobilized DNA transposon, Enterprise, from the model fungus Podospora anserina. Previously, we described a large genomic feature called the Spok block which is notable due to the presence of meiotic drive genes of the Spok gene family. The Spok block ranges from 110 kb to 247 kb and can be present in at least four different genomic locations within P. anserina, despite what is an otherwise highly conserved genome structure. We have determined that the reason for its varying positions is that the Spok block is not only capable of meiotic drive, but is also capable of transposition. More precisely, the Spok block represents a unique case where the Enterprise has captured the Spoks, thereby parasitizing a resident genomic parasite to become a genomic hyperparasite. Furthermore, we demonstrate that Enterprise (without the Spoks) is found in other fungal lineages, where it can be as large as 70 kb. Lastly, we provide experimental evidence that the Spok block is deleterious, with detrimental effects on spore production in strains which carry it. In contrast to the selfish role of the Enterprise in P. anserina, we speculate that the mobility of the Enterprise may also play an adaptive role in many other fungi, through the horizontal transfer of metabolic genes. This union of meiotic drivers and a transposon has created a selfish element of impressive size in Podospora, challenging our perception of how TEs influence genome evolution and broadening the horizons in terms of what the upper limit of transposition may be.
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| 9. |
- Kushnir, Duncan, 1979, et al.
(författare)
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Energy Requirements for production of carbon nanoparticles
- 2008
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Ingår i: Journal of Industrial Ecology. - : Wiley. - 1530-9290 .- 1088-1980. ; 12:3, s. 360-375
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Tidskriftsartikel (refereegranskat)abstract
- Energy requirements for fullerene and nanotube synthesis are calculated from literature data and presented for a number of important production processes, including fluidized bedand floating catalyst chemical vapor deposition (CVD), carbon monoxide disproportionation, pyrolysis, laser ablation,and electric arc and solar furnace synthesis. To produce data for strategic forward-looking assessments of the environmental implications of carbon nanoparticles, an attempt is made to balance generality with sufficient detail for individual processes, a trade-off that will likely be inherent in the analysis of many nanotechnologies. Critical energy and production issues are identified, and potential improvements in industrial-scale processes are discussed. Possible interactions with industrial ecosystems are discussed with a view toward integrating synthesis to mitigate the impacts of large-scale carbon nanoparticle manufacture. Carbon nanoparticles are found to be highly energy-intensive materials, on the order of 2 to 100 times more energy-intensive than aluminum, even with idealizedproduction models.
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| 10. |
- Tukker, Arnold, et al.
(författare)
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The Impacts of Household Consumption and Options for Change
- 2010
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Ingår i: Journal of Industrial Ecology. - : Wiley. - 1530-9290 .- 1088-1980. ; 14:1, s. 13-30
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- This introductory article situates the contributions that comprise this special issue within the field of sustainable consumption and production (SCP) studies. After a brief review of the policy history surrounding SCP, we organize our discussion and the subsequent collection of articles into two groups. The first suite of articles views the environmental impacts associated with household consumption from the perspectives of different consumer groups, income levels, and geographic areas. This work confirms and refines several insights that have been developing over the past several years, namely that food and beverages, mobility, housing, and energy-using products are the most critical consumption domains from the standpoint of environmental sustainability and that higher household income leads to greater (but less than proportional) impacts. The second subset of articles analyzes the potential for mitigating these impacts through behavioral changes and innovation strategies. Though the contributions to this special issue describe several noteworthy examples of information- and team-based initiatives to catalyze behavioral changes, the state of knowledge pertaining to this aspect of the consumption problematique is much more inchoate. Research on the formulation and implementation of effective "change management for sustainable consumption" should be treated as an area of priority attention for industrial ecologists.
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