| 1. |
- Hansson, Julia, et al.
(författare)
-
How is biodiversity protection influencing the potential for bioenergy feedstock production on grasslands?
- 2018
-
Ingår i: Global Change Biology Bioenergy. - : Wiley. - 1757-1693 .- 1757-1707. ; 11:3, s. 515-538
-
Tidskriftsartikel (refereegranskat)abstract
- Sustainable feedstock supply is a critical issue for the bioenergy sector. The sustainability criteria for biofuels in the EU Renewable Energy Directive (RED) prohibit the use of raw material from land with high biodiversity, i.e., areas designated for nature protection purposes, primary forest and highly biodiverse grassland. This paper addresses how biodiversity considerations influence the prospects for biomass production for bioenergy on grasslands. No globally established approach exists to assess and quantify grassland availability for bioenergy while considering biodiversity. We investigate how biodiverse grasslands are considered in (i) assessments of bioenergy supply potentials; (ii) the RED, the EU Common Agricultural Policy (CAP), and the UN Convention on Biological Diversity (CBD); and (iii) land-use governance and nature protection in Brazil. Estimates of biomass supply potentials commonly treat biodiverse grasslands as unavailable for bioenergy, when considering broader nature protection requirements. Few studies allow for a direct quantification of how biodiversity considerations relating to grasslands influence the global biomass supply potential. The definitions of natural and non-natural grassland in the RED are similar to those in the CAP. The RED complements and strengthens the protective ambitions in the CAP and CBD, but a lack of clear definitions and guidance in relation to the RED creates uncertainty about the prospects for biofuels from grasslands on the EU market. For EU-28, an estimated 39-48% (about 9-11 Mha) and 15-54% (about 10-38 Mha) of natural and non-natural grassland, respectively, may be considered highly biodiverse. In Brazil, economic-ecological zoning can be important for grassland conservation since almost half of the native grassland on private land is unprotected and subject to farmers’ preferences, which may favor protecting forest over grassland. Further clarification of grassland definitions and delineation in regulations will significantly influence the prospects for bioenergy from grasslands, and the impacts of bioenergy deployment on biodiversity.
|
|
| 2. |
- Hedman, Johannes, et al.
(författare)
-
A fast analysis system for forensic DNA reference samples
- 2008
-
Ingår i: Forensic Science International: Genetics. - : Elsevier BV. - 1878-0326 .- 1872-4973. ; 2:3, s. 184-189
-
Tidskriftsartikel (refereegranskat)abstract
- On January 1st, 2006, the Swedish legislation on obtaining DNA reference samples from Suspects and the recording of DNA profiles in databases was changed. As a result the number of samples analysed at the Swedish National Laboratory of Forensic Science (SKL) increased from about 4500 in 2005 to more than 25,000 in 2006. To meet this challenge, SKL launched a flew analysis system to create an unbroken chain, from sampling to incorporation of a profile in the national DNA database and subsequent automatic generation of digitally signed hit reports. The system integrates logistics, digital data transfer, new functions in LIMS (ForumDNA Version 4, Ida Infront AB) and laboratory automation. Buccal swab samples are secured on a FTA (R) card attached to an identity form, which is barcoded with a unique sample ID. After sampling, the police officer sends a digital request to SKL. The sample is automatically registered in LIMS and processed on delivery. The resulting DNA profiles are automatically classified according to quality using a custom-made expert system. Building the evaluation around mathematical rules makes it reproducible, standardised and minimises manual work and clerk errors. All samples are run in duplicate and the two profiles are compared within LIMS before incorporation in the database. In the first year of operation, the median time for completion of an analysis was 3 days, measured from delivery of the sample to incorporation of the profile in the national DNA database. In spite of the dramatic increase in the number of reference samples there was no backlog. (C) 2008 Elsevier Ireland Ltd. All rights reserved.
|
|
| 3. |
- Alvén, Jennifer, 1989, et al.
(författare)
-
A Deep Learning Approach to MR-less Spatial Normalization for Tau PET Images
- 2019
-
Ingår i: Medical Image Computing and Computer Assisted Intervention : MICCAI 2019 - 22nd International Conference, Proceedings - MICCAI 2019 - 22nd International Conference, Proceedings. - Cham : Springer International Publishing. - 1611-3349 .- 0302-9743. - 9783030322441 - 9783030322458 ; 11765 LNCS, s. 355-363
-
Konferensbidrag (refereegranskat)abstract
- The procedure of aligning a positron emission tomography (PET) image with a common coordinate system, spatial normalization, typically demands a corresponding structural magnetic resonance (MR) image. However, MR imaging is not always available or feasible for the subject, which calls for enabling spatial normalization without MR, MR-less spatial normalization. In this work, we propose a template-free approach to MR-less spatial normalization for [18F]flortaucipir tau PET images. We use a deep neural network that estimates an aligning transformation from the PET input image, and outputs the spatially normalized image as well as the parameterized transformation. In order to do so, the proposed network iteratively estimates a set of rigid and affine transformations by means of convolutional neural network regressors as well as spatial transformer layers. The network is trained and validated on 199 tau PET volumes with corresponding ground truth transformations, and tested on two different datasets. The proposed method shows competitive performance in terms of registration accuracy as well as speed, and compares favourably to previously published results.
|
|
| 4. |
|
|
| 5. |
- Lampinen, Björn, et al.
(författare)
-
Towards unconstrained compartment modeling in white matter using diffusion-relaxation MRI with tensor-valued diffusion encoding
- 2020
-
Ingår i: Magnetic Resonance in Medicine. - : Wiley. - 0740-3194 .- 1522-2594. ; 84:3, s. 1605-1623
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To optimize diffusion-relaxation MRI with tensor-valued diffusion encoding for precise estimation of compartment-specific fractions, diffusivities, and T2 values within a two-compartment model of white matter, and to explore the approach in vivo. Methods: Sampling protocols featuring different b-values (b), b-tensor shapes (bΔ), and echo times (TE) were optimized using Cramér-Rao lower bounds (CRLB). Whole-brain data were acquired in children, adults, and elderly with white matter lesions. Compartment fractions, diffusivities, and T2 values were estimated in a model featuring two microstructural compartments represented by a “stick” and a “zeppelin.”. Results: Precise parameter estimates were enabled by sampling protocols featuring seven or more “shells” with unique b/bΔ/TE-combinations. Acquisition times were approximately 15 minutes. In white matter of adults, the “stick” compartment had a fraction of approximately 0.5 and, compared with the “zeppelin” compartment, featured lower isotropic diffusivities (0.6 vs. 1.3 μm2/ms) but higher T2 values (85 vs. 65 ms). Children featured lower “stick” fractions (0.4). White matter lesions exhibited high “zeppelin” isotropic diffusivities (1.7 μm2/ms) and T2 values (150 ms). Conclusions: Diffusion-relaxation MRI with tensor-valued diffusion encoding expands the set of microstructure parameters that can be precisely estimated and therefore increases their specificity to biological quantities.
|
|
| 6. |
- Ranefjärd, Oskar, et al.
(författare)
-
Development of a hot-box test setup with dynamic outdoor climate
- 2019
-
Ingår i: Thermal Buildings XIV 2019.
-
Konferensbidrag (refereegranskat)abstract
- In Europe, all new houses built require an energy declaration showing the expected energy consumption during use. However, there is often a discrepancy between the calculated and the actual energy consumption. Some claim that in general the difference is on the positive side for wooden buildings, with real energy consumption being lower than predicted. This could be an effect of thorough and long-time work with energy related issues or it could be the bio based material performing better than designed. The working hypothesis for this paper is that materials with moisture buffering capacity have better energy performance when used in real structures under real climatic conditions compared to standard test of thermal insulation performance. The goal of this paper is therefore to develop an experimental procedure to test thermal insulation with different outdoor climates. The setup should also be suitable for various materials and different wall structures. With the objective to simulate a variety of outdoor climates, a Hot Box test was setup where one side of the experimental setup is a humidity- and temperature controlled climate chamber (outdoor side). The other side is a highly insulated box with temperature controlled heating, where the energy required to maintain the temperature is measured (indoor side). As validation of the test setup, steady-state values (as an ordinary Hot Box test) were compared against values obtained using a HotDisk apparatus. For common insulation materials as mineral wool and XPS, the results from Hot Box and HotDisk tests were very similar whereas there were differences for the bio based insulation material. Dynamic outdoor climate with diurnal changes does not result in apparent differences in the performance compared to the steady state Hot Box test for the tested materials, but there is reason to believe there is a difference with longer cycles.
|
|
| 7. |
- Ranefjärd, Oskar, et al.
(författare)
-
Investigating the Potential of Latent Heat in Hygroscopic Insulating Materials
- 2022
-
Ingår i: Thermal Performance of the Exterior Envelopes of Whole Buildings XV International Conference. - 2166-8469. - 9781955516280 ; , s. 85-94
-
Konferensbidrag (refereegranskat)abstract
- Energy from buildings accounts for almost 40% of global energy-related carbon emissions. A way to reduce both energy consumption in buildings as well as their environmental impact is to use bio-based insulation materials such as cellulose, wood or hemp fiber insulation. Experiences from modern buildings built with a timber-frame structure and insulated with bio-based materials show that these buildings have lower energy needs in the operational phase than what was initially expected from energy simulation models. However, these experiences have thus far been anecdotal, and they have not yet been validated through measurements. It is common that energy models only focus on thermal properties of materials and thermal flows through the building envelope, without considering moisture loads or hygrothermal behavior of building materials. A relevant difference between bio-based insulation materials and their polystyrene or mineral wool-based counterparts is that the former is more hygroscopic, with a generally high moisture capacity. It is hypothesized that latent heat and moisture transfer from the higher hygroscopicity of bio-based insulation materials could account for the discrepancy between modelled energy needs and measured energy needs in the operational phase. A numerical study was conducted to evaluate the energy performance of materials with varying hygroscopic properties. A numerical model of an exterior wall assembly with hygroscopic insulation materials was created in COMSOL, enabling parameters to be varied, without the manual input commonly required by some other commercial programs. Studied parameters included moisture buffering capacity and insulation thickness. Furthermore, the influence of the indoor and outdoor climate on the hygrothermal performance of the wall assembly was studied. The output evaluated focused primarily on the heat flux through the wall from the interior side. Results of the study showed that there is a potential for energy saving using hygroscopic insulation materials, as their higher moisture capacity could contribute to reduced energy needs for space heating. Results from this study also indicate that latent heat should be evaluated when insulation materials with hygroscopic properties are used in the building envelope, otherwise the energy use from heating could be underestimated.
|
|
| 8. |
- Ranefjärd, Oskar, et al.
(författare)
-
Parametric Study of Mould Risk in the Climate Envelope of Timber Buildings using Hydrothermal simulations
- 2019
-
Ingår i: Thermal Buildings XIV 2019.
-
Konferensbidrag (refereegranskat)abstract
- With global efforts in reducing energy consumption, house manufacturers are seeking use of new materials and design solutions. However, some believe this will increase the risk of mould. One way to assess the mould risk is to use a hygrothermal software for simulating the climate envelopes’ moisture performance. But as with all simulation, the quality of the output can never be better than the quality of the input. In moisture design, some parameters are only based on engineering judgement, which increases the uncertainty. The purpose of this paper is therefore to examine the risks and uncertainties of moisture safety design using hygrothermal simulations. The parametric study is done by using a factorial design and a mould risk assessment tool, Mould – Resistance Design (MRD), to identify what parameters are most influential in affecting the mould risk. The study includes common mould risks, as rain leakage and small air gaps, but also typical ways in which timber house manufacturers try to improve the moisture resistance. Some of the results were quite expected, e.g. the mould risk increases with water leakage closer to the timber frame. But the methodology also showed that changing the façade insulation to a PIR- insulation increases the mould risk more than the risk is decreased by the increased thermal insulation. The study also proves a point in that a lot of theincluded factors are just assumptions based on estimates while the real values are unknown, and they still are the most influential. Other parameters thathad significant importance are often neglected in moisture design, for instance the coefficient regarding wind driven rain and the temperature of the cladding.This paper further acknowledges that there are many and big obstacles in performing a good moisture safety assessment.
|
|
