| 721. |
- Liljenström, Carolina, et al.
(författare)
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Life cycle assessment as decision-support in choice of road corridor: case study and stakeholder perspectives
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The possibilities to influence environmental impacts during the road life cycle are greatest in early planning; however, the lack of project specific data makes it difficult to use life cycle assessment as decision-support. This paper examines how life cycle assessment can be used to support the choice of road corridor, considering the practical prerequisit of simplicity and usefulness of results for decision-making. The model LICCER was used to quantify life cycle impacts of road corridors in a construction project in Sweden. Availability of input data and usefulness of results was discussed with road authorities in Sweden, Norway, and Denmark. Traffic operation contributed most to life cycle impacts in all road corridors, thus the shortest construction alternative had the lowest life cycle impacts. However, the shortest alternative had the highest infrastructure related impacts due to large quantities of earthworks. Parameters that had the highest influence on results were those that affected the impacts of traffic, earthworks, and pavement. While workshop participants agreed that project specific data are scarce and uncertain in early planning, they also believed that planners can make satisfactory estimations and that the model output is useful to support the choice of road corridor. To balance simplicity and usefulness of results, data collection should focus on parameters that have high contribution to environmental impacts, that differentiate the road corridors, and are not proportional to the road length. To implement life cycle assessment in practice, models should preferably include nation specific data approved by the national road authority.
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| 722. |
- Liljenström, Carolina
(författare)
-
Life cycle assessment in early planning of transport systems : Decision support at project and network levels
- 2018
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The Swedish Climate Policy Framework implies that the Swedish transport sector must reduce its greenhouse gas emissions to nearly zero by 2045. Previous studies have – using life cycle assessment – shown that indirect greenhouse gas emissions from the vehicle and infrastructure life cycle are significant and should be considered in transport policy and planning of transport systems, in addition to direct emissions of vehicle operation.The aim of this thesis is to contribute with knowledge on climate impact and primary energy use of transport systems for decision-support in early planning at project and network levels, and evaluate and demonstrate how life cycle climate impact and primary energy use can be assessed in early planning. This thesis includes three papers that contribute to achieving this aim. Paper I developed a methodological approach to assess annual climate impact and primary energy use of Swedish road, rail, air, and sea transport infrastructure at a network level. Paper II then expanded this system to the assessment of the Swedish transport system at a network level, including national and international freight and passenger transport by road, rail, air, and sea. At the project level, Paper III examined how LCA can be used as decision-support in choice of road corridor, considering the practical prerequisite of data availability in early planning and usefulness of results in the decision-making process.Paper I showed that the annual climate impact of Swedish transport infrastructure is around 3 million tonnes CO2 equivalents and that the annual primary energy use is around 27 TWh. Road infrastructure accounted for the largest proportion of impacts – around 70% of the climate impact and around 80% of the energy use. Paper II showed that the annual climate impact of the Swedish transport system was around 44 million tonnes CO2 equivalents and the primary energy use was around 178 TWh. Road transport and aviation together accounted for 90% of the climate impact and primary energy use. Indirect impacts were significant, especially for road and rail transport, accounting for 30% of the total climate impact and primary energy use. Paper III found that (1) collection of project specific data should focus on parameters that differentiate the road corridors, that can be influenced in early planning, and that are not directly related to the road length and (2) life cycle assessment based models used in early planning should include nation specific generic data approved by the national road authority.
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| 723. |
- Liljenström, Carolina
(författare)
-
Life cycle assessment of transport systems and transport infrastructure : Investigating methodological approaches and quantifying impacts at project and network levels
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Reducing greenhouse gas emissions from the transport sector is a key challenge to reach global climate targets and limit global warming to below 2 ºC. The use of life cycle assessment (LCA) may provide knowledge about the environmental impacts of transport systems so that emission reduction measures can be identified.The aim of this thesis is to investigate how LCA can contribute with knowledge that can be used to support specific decisions in the context of transport system policy and planning, to demonstrate how LCA can be conducted at project and network levels, and to contribute with knowledge of direct and indirect climate impact and primary energy use of the Swedish transport infrastructure and the Swedish transport system at a network level.The thesis includes four papers that contribute to achieving this aim. Paper 1 demonstrates an approach for the identification of hotspots in Swedish road, rail, air, and sea transport infrastructure at a network level. Paper 2 demonstrates this approach for the full transport system at a network level, including national and international freight transport and passenger travel by road, rail, air, and sea. At the project level, Paper 3 investigates how LCA can be used as decision-support in choice of road corridor, considering prerequisites of data availability and usefulness of results for decision-making. Paper 4 maps approaches used to quantify impacts of the maintenance stage in 92 project-level LCAs of road and rail infrastructure and discusses their applicability in policy and procurement.Paper 1 estimated that the annual climate impact of Swedish transport infrastructure is about 3 Mtonne CO2 equivalents and that the corresponding primary energy use is about 27 TWh. Road and rail infrastructure contributed to 90% of these impacts. Additional hotspots identified were reinvestment of roads and railways and production of asphalt, concrete, and steel. Paper 2 estimated that the annual climate impact of the Swedish transport system is about 40 Mtonne CO2 equivalents and that the corresponding primary energy use is about 196 TWh. Road transport and aviation together accounted for 85% of these impacts. Indirect impacts were significant, accounting for about a third of the impacts. The main causes of indirect impacts were fuel production for road passenger travel and manufacturing of passenger cars.Paper 3 found that LCA-based models used in early planning should include generic data that are nation specific (preferably approved by the national road authority) and that can be replaced by project specific data when needed. Further, both traffic and infrastructure should be included at a level of detail that allows the identification of improvement measures and the assessment of uncertainty in the results. Results should be presented relative to a reference alternative and complement results from other decision-support used in planning. Paper 4 found a variety of approaches to quantify impacts of the maintenance stage in LCA. The analysis period was often determined based on the infrastructure’s service life. The maintenance frequency was commonly estimated based on the current practice of maintenance in a region or on performance prediction modelling. Only two of the reviewed papers included the effects of climate change on results of the LCA. How the approaches can be implemented in decision-making depends on their abilities to be standardised for use in procurement and to incorporate multiple scenarios.Stakeholders involved in transport system policy and planning can use these results as support in considering life cycle impacts in their decision-making practice to reduce environmental impacts in line with national and international targets.
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| 724. |
- Liljenström, Hans
(författare)
-
Peak experiences in a consciousness landscape - report on the science of consciousness conference in Interlaken, Switzerland, 2019
- 2019
-
Ingår i: Journal of Consciousness Studies. - 1355-8250. ; 26, s. 238-263
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Introduction The Science of Consciousness (TSC) 2019 was the 26th international interdisciplinary conference in the series that started in Tucson in 1994. This one was held in late June in the beautiful Swiss town of Interlaken, between two lakes and surrounded by high alps. The local organizer was Harald Atmanspacher from Collegium Helveticum in Zurich, assisted by the “eternal” main organizer, Stuart Hameroff from the Center for Consciousness Studies in Tucson. There was no special theme for this conference, but I agree with the introductory comment in the abstract book: “Despite remarkable empirical and theoretical progress, consciousness is not understood yet, and therefore the field will benefit from a healthy scientific attitude that includes openness to multiple perspectives”. This was certainly applicable here. The beautiful alpine landscape provided a perfect setting for the conference, but the unexpectedly hot weather made it hard to concentrate and contemplate on the deep questions discussed. Yet, the organizers had done what they could to make the conference welcoming and inspiring for the 620 participants from about 30 countries. There were in total 24 invited talks in 9 plenary sessions, 105 oral presentations in concurrent sessions, and 220 posters - on topics, such as connectomics, placebo research, first-person experience, anesthetics, psychedelics, plant cognition, quantum biology, dual-aspect monism, bistable perception, insight, religious studies, evolution, and language. More details on the conference, including video recordings of the plenary talks are available on the website, www.tsc2019-interlaken.ch. This will be a very subjective report, where I have cherry-picked among the talks I attended, primarily focusing on the plenaries, but with some visits to concurrent sessions. In addition, I will not give equal amount of space to all the presentations I refer to, and apologize if anyone feels mistreated that way. It also goes without saying that the report is biased with respect to my own research interests, as a biophysicist working with neurocomputational models of decision making, based on mesoscopic neurodynamics. Inspired by the surrounding alpine landscape, I think it could serve as a metaphor for the mental landscape and intellectual challenges we have to climb when trying to understand the ancient conundrum of consciousness. The perspectives provided by various research areas, can then be likened with different alps, with rather deep valleys between. Somewhat arbitrary, I will structure my report around three major peak perspectives, Physics, Biology, and Metaphysics, where I have roughly and not chronologically grouped the various presentations.
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| 725. |
- Lin, Lili, et al.
(författare)
-
Elastic and inelastic electron transport in metal-molecule(s)-metal junctions
- 2013
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Ingår i: Physica. E, Low-Dimensional systems and nanostructures. - : Elsevier BV. - 1386-9477 .- 1873-1759. ; 47, s. 167-187
-
Forskningsöversikt (refereegranskat)abstract
- An overview of studies on-elastic and inelastic electron transport properties of molecular junction devices is presented. The development of the experimental fabrication and characterization of molecular junctions as well as the corresponding theoretical modeling is briefly summarized. The functions of molecular devices are generally governed by the intrinsic structure-property relationships, and strongly affected by various environment factors including temperature, solvent and intermolecular interactions. Those detailed structural and environmental information could be probed by a powerful tool of inelastic electron tunneling spectroscopy, for which the theoretical modeling becomes particularly important. With many successful examples, it is demonstrated that the combination of theoretical simulations and experimental measurements can help not only to understand the electron-phonon interaction, but more importantly also to accurately determine the real configurations of molecules inside the junctions.
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| 726. |
- Lin, Zhipeng, et al.
(författare)
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Electrocatalyzed direct arene alkenylations without directing groups for selective late-stage drug diversification
- 2023
-
Ingår i: Nature Communications. - 2041-1723. ; 14:1
-
Tidskriftsartikel (refereegranskat)abstract
- Electrochemistry has emerged as an increasingly viable tool in molecular synthesis. Here the authors realize electrocatalyzed C-H activations, with the aid of data science and artificial intelligence, towards selective alkenylations for late-stage drug diversifications. Electrooxidation has emerged as an increasingly viable platform in molecular syntheses that can avoid stoichiometric chemical redox agents. Despite major progress in electrochemical C-H activations, these arene functionalizations generally require directing groups to enable the C-H activation. The installation and removal of these directing groups call for additional synthesis steps, which jeopardizes the inherent efficacy of the electrochemical C-H activation approach, leading to undesired waste with reduced step and atom economy. In sharp contrast, herein we present palladium-electrochemical C-H olefinations of simple arenes devoid of exogenous directing groups. The robust electrocatalysis protocol proved amenable to a wide range of both electron-rich and electron-deficient arenes under exceedingly mild reaction conditions, avoiding chemical oxidants. This study points to an interesting approach of two electrochemical transformations for the success of outstanding levels of position-selectivities in direct olefinations of electron-rich anisoles. A physical organic parameter-based machine learning model was developed to predict position-selectivity in electrochemical C-H olefinations. Furthermore, late-stage functionalizations set the stage for the direct C-H olefinations of structurally complex pharmaceutically relevant compounds, thereby avoiding protection and directing group manipulations.
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| 727. |
- Lindahl, Camilla
(författare)
-
Sign Bilingualism as Semiotic Resource in Science Education : What Does It Mean?
- 2021
-
Ingår i: Critical Perspectives on Plurilingualism in Deaf Education. - Bristol : Multilingual Matters. - 9781800410749 - 9781800410732 - 9781800410756 - 9781800410763 ; , s. 129-148
-
Bokkapitel (refereegranskat)abstract
- Developing a scientific dialogue with students in the sign bilingual science classroom implies some challenges. The aim of this chapter is to illustrate how Swedish sign language and Swedish in written form contribute to joint meaning making in science education. This sign bilingualism, together with other modalities in the science classroom such as tables, charts, test tubes and Bunsen burners, was analyzed from a multimodal social semiotic perspective. This chapter discusses what it means to communicate science in sign language in relation to terms, concepts and models in the written majority language. The development of instructional strategies in the linguistically complex teaching environment supports deaf students’ ability to develop their knowledge in science, including the use of scientific language in both sign language and spoken/written language.
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| 728. |
- Lindahl, Camilla, 1969-
(författare)
-
Tecken av betydelse : En studie av dialog i ett multimodalt, teckenspråkigt tvåspråkigt NO-klassrum.
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Ett gemensamt meningsskapande i skolans naturvetenskapliga klassrum förutsätter en interaktion som i allt högre grad kommer att präglas av ett naturvetenskapligt språkbruk. Utvecklingen av ett naturvetenskapligt ämnesspråk innebär ofta en stor utmaning för flerspråkiga elever som lär sig naturvetenskap på sitt andraspråk och vars behov av stöttning därför är särskilt stort. Denna studie utforskar döva och hörselskadade elevers lärande naturvetenskap i ett tvåspråkigt NO-klassrum där meningsskapandet sker genom svenskt teckenspråk och skriven svenska. Avhandlingens övergripande frågor är hur svenskt teckenspråk och svenska används i dialogen och hur dessa språk, i interaktion med andra modaliteter, bidrar till meningsskapandet i naturvetenskap. En grupp på två lärare och åtta elever, alla döva och teckenspråkig tvåspråkiga, filmades i totalt sjutton NO-lektioner. Klassrumskommunikation i denna teckenspråkigt tvåspråkiga miljö med naturvetenskapliga artefakter som modeller, tabeller och övrig naturvetenskaplig utrustning analyseras sedan från ett multimodalt socialsemiotiskt perspektiv där språk och modaliteter diskuteras som potentiella resurser i meningsskapandet. Resultaten visar en komplex dialog där språk och modaliteter hela tiden växlar på ett sätt som starkt bidrar till att driva dialogen framåt. Vidare framstår det visuella-gestuella teckenspråket som en kraftfull modalitet. I synnerhet spelar avbildande tecken en framträdande roll i dialogen och i det naturvetenskapliga meningsskapandet. Språkväxlingar i den teckenspråkiga dialogen sker dynamiskt i form av sömlösa och spontana växlingar men utnyttjas även som pedagogiskt verktyg. Teckenspråkets kontextbundenhet kräver dessutom ibland tvärspråkliga resonemang på metanivå där oklarheter såväl som likheter och skillnader mellan olika språkliga uttryck kan redas ut. Resultaten uppmärksammar också lärarnas viktiga roll för att stötta eleverna i det naturvetenskapliga meningsskapandet liksom för utvecklingen av ett naturvetenskapligt språk. I diskussionen lyfts behovet av pedagogiska strategier som stärker stöttningen av döva och hörselskadade elevers teckenspråkiga tvåspråkiga meningsskapande i naturvetenskap.
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| 729. |
- Lindahl, Mats, 1955-, et al.
(författare)
-
How do 15-16 year old students use scientific knowledge to justify their reasoning about human sexuality and relationships?
- 2016
-
Ingår i: Teaching and Teacher Education. - : Elsevier BV. - 0742-051X .- 1879-2480. ; 60:November, s. 121-130
-
Tidskriftsartikel (refereegranskat)abstract
- In order to advance our understanding about the roles studentsassign to expert knowledge, the present study addresses how secondaryschool students use their knowledge of scientific disciplines in theirreasoning of socioscientific issues (SSI). Through group discussions, theresults show that students use science either as a sole justification orintegrated with other kinds of knowledge. Using expert knowledge to liftproblems out of the limited local contexts and find solutions, thestudents access the freedom to make personal choices. Thus, it wasconcluded that scientific knowledge provides possibilities for decisionsthat can support students' agency.
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| 730. |
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