| 1. |
- Chursa, Urszula, et al.
(författare)
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Overexpression of protein kinase STK25 in mice exacerbates ectopic lipid accumulation, mitochondrial dysfunction and insulin resistance in skeletal muscle.
- 2017
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Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 1432-0428 .- 0012-186X. ; 60:3, s. 553-567
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the molecular networks controlling ectopic lipid deposition and insulin responsiveness in skeletal muscle is essential for developing new strategies to treat type 2 diabetes. We recently identified serine/threonine protein kinase 25 (STK25) as a critical regulator of liver steatosis, hepatic lipid metabolism and whole body glucose and insulin homeostasis. Here, we assessed the role of STK25 in control of ectopic fat storage and insulin responsiveness in skeletal muscle.Skeletal muscle morphology was studied by histological examination, exercise performance and insulin sensitivity were assessed by treadmill running and euglycaemic-hyperinsulinaemic clamp, respectively, and muscle lipid metabolism was analysed by ex vivo assays in Stk25 transgenic and wild-type mice fed a high-fat diet. Lipid accumulation and mitochondrial function were also studied in rodent myoblasts overexpressing STK25. Global quantitative phosphoproteomics was performed in skeletal muscle of Stk25 transgenic and wild-type mice fed a high-fat diet to identify potential downstream mediators of STK25 action.We found that overexpression of STK25 in transgenic mice fed a high-fat diet increases intramyocellular lipid accumulation, impairs skeletal muscle mitochondrial function and sarcomeric ultrastructure, and induces perimysial and endomysial fibrosis, thereby reducing endurance exercise capacity and muscle insulin sensitivity. Furthermore, we observed enhanced lipid accumulation and impaired mitochondrial function in rodent myoblasts overexpressing STK25, demonstrating an autonomous action for STK25 within cells. Global phosphoproteomic analysis revealed alterations in the total abundance and phosphorylation status of different target proteins located predominantly to mitochondria and sarcomeric contractile elements in Stk25 transgenic vs wild-type muscle, respectively, providing a possible molecular mechanism for the observed phenotype.STK25 emerges as a new regulator of the complex interplay between lipid storage, mitochondrial energetics and insulin action in skeletal muscle, highlighting the potential of STK25 antagonists for type 2 diabetes treatment.
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| 2. |
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| 3. |
- Johansson, Fredrik, 1973-, et al.
(författare)
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Investigation of research needs regarding the storage of hydrogen gas in lined rock caverns : Prestudy for Work Package 2.3 in HYBRIT Research Program 1
- 2018
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The objective of HYBRIT RP1 is to explore and assess pathways to fossil-free energy-mining-iron-steel value chains and thereby provide a basis for industrial development activities and the necessary future transformative change in this field. A large-scale storage capacity for hydrogen gas is an important component of the proposed HYBRIT concept. Underground storage in lined rock caverns provides a reasonable option: a large-scale demonstration plant for storage of natural gas was constructed in Sweden in 2002 and has operated safely since then. Considering that this lined rock cavern facility was constructed for natural gas, the present report investigates the current research needs to allow for underground storage of hydrogen gas in such a facility. This will serve as a basis for the research in Work Package 2.3 of HYBRIT RP1.Studying the experiences from decades of Swedish and international research and practice on the construction of underground gas storage facilities, the conclusion is that the lined rock cavern concept seems a reasonable way forward. In terms of rock engineering research, there are currently no critical research issues; however, a development of a previously proposed risk-based design framework for lined rock caverns may further strengthen the ability to manage risks related to underground gas storage facilities. The report identifies several potential research questions on this topic to be further studied: development of a risk-based design approach using subset simulation, the optimization potential of the concrete thickness in the lining, and the effect of spatial variation of rock mass properties on a location’s suitability for the storage facility.Additionally, the report identifies the potential effect of hydrogen embrittlement on the steel lining as a critical research issue to ensure safe storage of hydrogen gas in lined rock caverns. However, as this issue is not related to rock engineering, but a material issue, it will not be covered further in Work Package 2.3.
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| 4. |
- Johansson, Malin E V, 1971, et al.
(författare)
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Normalization of Host Intestinal Mucus Layers Requires Long-Term Microbial Colonization
- 2015
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Ingår i: Cell Host & Microbe. - : Elsevier BV. - 1931-3128 .- 1934-6069. ; 18:5, s. 582-592
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Tidskriftsartikel (refereegranskat)abstract
- The intestinal mucus layer provides a barrier limiting bacterial contact with the underlying epithelium. Mucus structure is shaped by intestinal location and the microbiota. To understand how commensals modulate gut mucus, we examined mucus properties under germ-free (GF) conditions and during microbial colonization. Although the colon mucus organization of GF mice was similar to that of conventionally raised (Convr) mice, the GF inner mucus layer was penetrable to bacteria-sized beads. During colonization, in which GF mice were gavaged with Convr microbiota, the small intestine mucus required 5 weeks to be normally detached and colonic inner mucus 6 weeks to become impenetrable. The composition of the small intestinal microbiota during colonization was similar to Convr donors until 3 weeks, when Bacteroides increased, Firmicutes decreased, and segmented filamentous bacteria became undetectable. These findings highlight the dynamics of mucus layer development and indicate that studies of mature microbe-mucus interactions should be conducted weeks after colonization.
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| 5. |
- Petersson, Malin, et al.
(författare)
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Patient-reported symptom severity in a nationwide myasthenia gravis cohort : cross-sectional analysis of the Swedish GEMG study
- 2021
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Ingår i: Neurology. - : Lippincott Williams & Wilkins. - 0028-3878 .- 1526-632X. ; 97:14, s. e1382-e1391
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Tidskriftsartikel (refereegranskat)abstract
- Background and Objectives: To describe myasthenia gravis activities of daily living (MG-ADL) in relation to clinical characteristics in a large Swedish nationwide cohort.Methods: In a cross-sectional prevalence cohort study, the Genes and Environment in Myasthenia Gravis study, performed from November 2018 through August 2019, patients with myasthenia gravis (MG) were invited to submit an extensive 106-item life environment questionnaire, including the MG-ADL score. Patients were classified into early-onset MG (EOMG, <50 years), late-onset MG (LOMG, >= 50 years), or thymoma-associated MG (TAMG). Comparisons of disease-specific characteristics were made between subgroups, sexes, and different MG-ADL scores.Results: A total of 1,077 patients were included, yielding a 74% response rate: 505 (47%) were classified as EOMG, 520 (48%) LOMG, and 45 (4%) TAMG. Mean age at inclusion was 64.3 years (SD 15.7) and mean disease duration was 14.6 years (SD 14.0). Complete MG-ADL scores (n = 1,035) ranged from 0p to 18p, where 26% reported a score of 0p. Higher MG-ADL scores were associated with female sex, obesity, and diagnostic delay (odds ratio [OR] 1.62, 1.72, and 1.69; p(adj) = 0.017, 0.013, and 0.008) and inversely correlated with high educational attainment (OR 0.59; p(adj) = 0.02), but not with age at inclusion, disease subtype, or disease duration. Almost half of the population (47%) reported MG-ADL >= 3p, corresponding to an unsatisfactory symptom state.Discussion: In this nationwide study, comprising more than 40% of the prevalent MG population in Sweden, almost half of the patients reported current disease symptoms associated with an unsatisfactory symptom state, indicating the need for improved treatment options.
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| 6. |
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| 7. |
- Abbaszadeh Shahri, Abbas, et al.
(författare)
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Landslide susceptibility hazard map in southwest Sweden using artificial neural network
- 2019
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Ingår i: Catena (Cremlingen. Print). - : ELSEVIER. - 0341-8162 .- 1872-6887. ; 183
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Tidskriftsartikel (refereegranskat)abstract
- Landslides as major geo-hazards in Sweden adversely impact on nearby environments and socio-economics. In this paper, a landslide susceptibility map using a proposed subdivision approach for a large area in southwest Sweden has been produced. The map has been generated by means of an artificial neural network (ANN) model developed using fourteen causative factors extracted from topographic and geomorphologic, geological, land use, hydrology and hydrogeology characteristics. The landslide inventory map includes 242 events identified from different validated resources and interpreted aerial photographs. The weights of the causative factors employed were analyzed and verified using accepted mathematical criteria, sensitivity analysis, previous studies, and actual landslides. The high accuracy achieved using the ANN model demonstrates a consistent criterion for future landslide susceptibility zonation. Comparisons with earlier susceptibility assessments in the area show the model to be a cost-effective and potentially vital tool for urban planners in developing cities and municipalities.
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| 8. |
- Abbaszadeh Shahri, Abbas, et al.
(författare)
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Normalizing Large Scale Sensor-Based MWD Data : An Automated Method toward A Unified Database
- 2024
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Ingår i: Sensors. - : MDPI AG. - 1424-8220. ; 24:4
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Tidskriftsartikel (refereegranskat)abstract
- In the context of geo-infrastructures and specifically tunneling projects, analyzing the large-scale sensor-based measurement-while-drilling (MWD) data plays a pivotal role in assessing rock engineering conditions. However, handling the big MWD data due to multiform stacking is a time-consuming and challenging task. Extracting valuable insights and improving the accuracy of geoengineering interpretations from MWD data necessitates a combination of domain expertise and data science skills in an iterative process. To address these challenges and efficiently normalize and filter out noisy data, an automated processing approach integrating the stepwise technique, mode, and percentile gate bands for both single and peer group-based holes was developed. Subsequently, the mathematical concept of a novel normalizing index for classifying such big datasets was also presented. The visualized results from different geo-infrastructure datasets in Sweden indicated that outliers and noisy data can more efficiently be eliminated using single hole-based normalizing. Additionally, a relational unified PostgreSQL database was created to store and automatically transfer the processed and raw MWD as well as real time grouting data that offers a cost effective and efficient data extraction tool. The generated database is expected to facilitate in-depth investigations and enable application of the artificial intelligence (AI) techniques to predict rock quality conditions and design appropriate support systems based on MWD data.
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| 9. |
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| 10. |
- Abbaszadeh Shahri, Abbas, et al.
(författare)
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Updated relations for the uniaxial compressive strength of marlstones based on P-wave velocity and point load index test
- 2016
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Ingår i: INNOVATIVE INFRASTRUCTURE SOLUTIONS. - : SPRINGER INTERNATIONAL PUBLISHING AG. - 2364-4176 .- 2364-4184. ; 1:1
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Tidskriftsartikel (refereegranskat)abstract
- Although there are many proposed relations for different rock types to predict the uniaxial compressive strength (UCS) as a function of P-wave velocity (V-P) and point load index (Is), only a few of them are focused on marlstones. However, these studies have limitations in applicability since they are mainly based on local studies. In this paper, an attempt is therefore made to present updated relations for two previous proposed correlations for marlstones in Iran. The modification process is executed through multivariate regression analysis techniques using a provided comprehensive database for marlstones in Iran, including UCS, V-P and Is from publications and validated relevant sources comprising 119 datasets. The accuracy, appropriateness and applicability of the obtained modifications were tested by means of different statistical criteria and graph analyses. The conducted comparison between updated and previous proposed relations highlighted better applicability in the prediction of UCS using the updated correlations introduced in this study. However, the derived updated predictive models are dependent on rock types and test conditions, as they are in this study.
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| 11. |
- Andersson, Fredrik, 1974-, et al.
(författare)
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Female top management in family firms and non-family firms : Evidence from total population data
- 2018
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Ingår i: International Journal of Entrepreneurship and Small Business. - : InderScience Publishers. - 1476-1297 .- 1741-8054. ; 35:3, s. 303-326
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Tidskriftsartikel (refereegranskat)abstract
- We exploit information on ownership, management and kinship to study the representation of women in top management teams in Swedish family and non-family firms among domiciled limited liability firms over the years 2004 to 2010. The share of female top managers is analysed across listed and non-listed firms as well as across industries. We then estimate the likelihood that a woman is elected into the top management team in family and non-family firms using a probit regression model where we control for firm- A nd individual-level characteristics, including the gender distribution of the firm and kinship relations to existing board members and firm owners. We find that non-listed family firms are more likely to appoint female top managers, whereas we find no differences among listed firms. Moreover, we find that the gender composition and kinship structures of firms influence the appointment of female top managers.
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| 12. |
- Andersson, Fredrik, 1974-, et al.
(författare)
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The Characteristics and Performance of Family Firms : Exploiting information on ownership, governance and kinship using total population data
- 2017
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Rapport (refereegranskat)abstract
- Family firms are often considered characteristically different from non-family firms, and the economic implications of these differences have generated significant academic debate. However, our understanding of family firms suffers from an inability to identify them in total population data, as this requires information on owners, their kinship and involvement in firm governance, which is rarely available. We present a method for identifying domiciled family firms using register data that offers greater accuracy than previous methods. We then apply it to data from Statistics Sweden concerning firm ownership, governance and kinship over the years 2004-2010. Next, we use Swedish data to estimate these firms’ economic contribution to total employment and gross domestic product (GDP) and compare them to private domiciled non-family firms in terms of their characteristics and economic performance. We find that the family firm is the prevalent organizational form, contributing to over one-third of all employment and GDP. Family firms are common across industries and sizes, ranging from the smallest producers to the largest multinational firms. However, their characteristics differ across sizes and legal forms, thereby indicating that the seemingly contradictory findings among previous studies on family firms may be due to unobserved heterogeneity. We furthermore find that they are smaller than private non-family firms in employment and sales and carry higher solidity, although they are more profitable. These differences diminish with firm size, however. We conclude that the term ‘family firm’ contains great diversity and call for increased attention to their heterogeneity.
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| 13. |
- Andersson, Fredrik, 1974-, et al.
(författare)
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The Characteristics of Family Firms : Exploiting Information on Ownership, Kinship and Governance Using Total Population Data
- 2018
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Ingår i: Small Business Economics. - : Kluwer Academic/Plenum Publishers. - 0921-898X .- 1573-0913. ; 51:3, s. 539-556
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Tidskriftsartikel (refereegranskat)abstract
- Family firms are often considered characteristically different from non-family firms. However, our understanding of family firms suffers from an inability to identify them in total population data; information is rarely available regarding owners, their kinship, and their involvement in firm governance. We present a method for identifying domiciled family firms using register data; this method offers greater accuracy than previous methods. We apply this method to Swedish data concerning firm ownership, governance, and kinship from 2004 to 2010. We find that the family firm is a significant organizational form, contributing over one third of all employment and gross domestic product (GDP). Family firms are common in most industries and range in size. Furthermore, we find that, compared to private non-family firms, family firms have fewer total assets, employment, and sales and carry higher solidity, although family firms are more profitable. These differences diminish with firm size. We conclude that the term “family firm” includes a large variety of firms, and we call for increased attention to their heterogeneity.
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| 14. |
- Arike, Liisa, et al.
(författare)
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Protein Turnover in Epithelial Cells and Mucus along the Gastrointestinal Tract Is Coordinated by the Spatial Location and Microbiota
- 2020
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Ingår i: Cell Reports. - : Elsevier BV. - 2211-1247. ; 30:4, s. 1077-1087
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Tidskriftsartikel (refereegranskat)abstract
- The gastrointestinal tract is covered by a single layer of epithelial cells that, together with the mucus layers, protect the underlying tissue from microbial invasion. The epithelium has one of the highest turnover rates in the body. Using stable isotope labeling, high-resolution mass spectrometry, and computational analysis, we report a comprehensive dataset of the turnover of more than 3,000 and the expression of more than 5,000 intestinal epithelial cell proteins, analyzed under conventional and germ-free conditions across five different segments in mouse intestine. The median protein half-life is shorter in the small intestine than in the colon. Differences in protein turnover rates along the intestinal tract can be explained by distinct physiological and immune-related functions between the small and large intestine. An absence of microbiota results in an approximately 1 day longer protein half-life in germ-free animals.
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| 15. |
- Arora, Tulika, et al.
(författare)
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Microbial regulation of the L cell transcriptome
- 2018
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 8:1
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Tidskriftsartikel (refereegranskat)abstract
- L cells are an important class of enteroendocrine cells secreting hormones such as glucagon like peptide-1 and peptide YY that have several metabolic and physiological effects. The gut is home to trillions of bacteria affecting host physiology, but there has been limited understanding about how the microbiota affects gene expression in L cells. Thus, we rederived the reporter mouse strain, GLU-Venus expressing yellow fluorescent protein under the control of the proglucagon gene, as germ-free (GF). Lpos cells from ileum and colon of GF and conventionally raised (CONV-R) GLU-Venus mice were isolated and subjected to transcriptomic profiling. We observed that the microbiota exerted major effects on ileal L cells. Gene Ontology enrichment analysis revealed that microbiota suppressed biological processes related to vesicle localization and synaptic vesicle cycling in Lpos cells from ileum. This finding was corroborated by electron microscopy of Lpos cells showing reduced numbers of vesicles as well as by demonstrating decreased intracellular GLP-1 content in primary cultures from ileum of CONV-R compared with GF GLU-Venus mice. By analysing Lpos cells following colonization of GF mice we observed that the greatest transcriptional regulation was evident within 1 day of colonization. Thus, the microbiota has a rapid and pronounced effect on the L cell transcriptome, predominantly in the ileum. © 2018 The Author(s).
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| 16. |
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| 17. |
- Bista, Dipen, et al.
(författare)
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Influence of location of large-scale asperity on shear strength of concrete-rock interface under eccentric load
- 2020
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Ingår i: Journal of Rock Mechanics and Geotechnical Engineering. - : Elsevier BV. - 1674-7755. ; 12:3, s. 449-460
-
Tidskriftsartikel (refereegranskat)abstract
- The location and geometry of large-scale asperity present at the foundation of concrete gravity dams and buttress dams affect the shear resistance of the concrete-rock interface. However, the parameters describing the frictional resistance of the interface usually do not account for these asperities. This could result in an underestimate of the peak shear strength, which leads to significantly conservative design for new dams or unnecessary stability enhancing measures for existing ones. The aim of this work was to investigate the effect of the location of first-order asperity on the peak shear strength of a concrete-rock interface under eccentric load and the model discrepancy associated with the commonly used rigid body methods for calculating the factor of safety (FS) against sliding. For this, a series of direct and eccentric shear tests under constant normal load (CNL) was carried out on concrete-rock samples. The peak shear strengths measured in the tests were compared in terms of asperity location and with the predicted values from analytical rigid body methods. The results showed that the large-scale asperity under eccentric load significantly affected the peak shear strength. Furthermore, unlike the conventional assumption of sliding or shear failure of an asperity in direct shear, under the effect of eccentric shear load, a tensile failure in the rock or in the concrete could occur, resulting in a lower shear strength compared with that of direct shear tests. These results could have important implications for assessment of the FS against sliding failure in the concrete-rock interface.
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| 18. |
- Bjureland, William, 1987-, et al.
(författare)
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Dimensionering av sprutbetongförstärkning för lösa block med sannolikhetsbaserade metoder
- 2020
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Konferensbidrag (populärvet., debatt m.m.)abstract
- Användning av sannolikhetsbaserade metoder för dimensionering av bergförstärkning är ett tillvägagångssätt som är accepterat i Eurokoderna. Vid dimensionering med dessa metoder beaktas osäkerheter stringent genom att ansätta sannolikhetsfördelningar för relevanta parametrar. Konstruktionens säkerhet säkerställs genom att verifiera att sannolikheten att överskrida bärförmågan är lägre än den i Eurokoderna kravställda brottsannolikheten. För tillämpning av sannolikhetsbaserade metoder för dimensionering av sprutbetongförstärkning för lösa block har ett problem varit att data saknats för att kunna beskriva relevanta parametrar med representativa sannolikhetsfördelningar. Dessutom samverkar de olika brottmoderna och måste därför betraktas ur ett systemperspektiv, vilket inte beaktats i tidigare studier. I denna artikel presenteras resultatet av ett doktorandprojekt med finansiering av SBUF, BeFo, SVC och SKB. Baserat på ovanstående aspekter presenteras en metodik för dimensionering av sprutbetongförstärkning för lösa block med sannolikhetsbaserade metoder. Inledningsvis presenteras sannolikhetsfördelningar för sprutbetongens parametrar baserat på en stor mängd analyserade data från Citybanan. Därefter presenteras den utvecklade dimensioneringsmetodiken, vilken bygger på att en initial dimensionering av sprutbetongen utförs innan tunneldrivningen påbörjas och att den applicerade sprutbetongens bärförmåga därefter verifieras med hjälp av kontrollmätningar från fält och Bayesiansk statistik.
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| 19. |
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| 20. |
- Bjureland, William, 1987-, et al.
(författare)
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Influence of spatially varying thickness on load-bearing capacity of shotcrete
- 2020
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Ingår i: Tunnelling and Underground Space Technology. - : Elsevier. - 0886-7798 .- 1878-4364. ; 98
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Tidskriftsartikel (refereegranskat)abstract
- A common approach to verify a shotcrete layer's ability to secure blocks that can exist between rockbolts in a tunnel is to use analytical calculations. For this situation, an attractive approach to account for variability in the shotcrete parameters is to use reliability-based methods. Variability can then be accounted for by assigning suitable probability distributions to all relevant input parameters. Structural safety can be ensured by verifying that the probability of limit exceedance is smaller than an acceptable target probability of failure. However, even though analytical calculations and reliability-based methods can be used to design shotcrete support, one of the commonly made basic assumptions is that the load-bearing capacity of the shotcrete is governed by the spatial average of the input parameters. Thus, the spatial variability of the parameters are neglected. As a result, if the capacity is governed by the lowest value of a certain parameter, this assumption is non-conservative. In this paper, we present a novel approach in which the minimum of either the spatial average of a shotcrete slab of varying thickness, or the spatial average along the periphery of a loose block of that same slab, is used to estimate the load-bearing capacity of the shotcrete in a tunnel. The approach is based on results from numerical simulations of a shotcrete slab that we perform to investigate the effect that a spatially varying thickness has on the flexural load-bearing capacity of the slab. The results from the simulations show that the shotcrete's flexural load-bearing capacity might be overestimated when using the spatial average of shotcrete thickness between four rockbolts in design. Using the presented approach, the spatial variability of shotcrete thickness can be accounted for in practical design of tunnels without complex and time-consuming numerical simulations.
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| 21. |
- Bjureland, William, et al.
(författare)
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Probability distributions of shotcrete parameters for reliability-based analyses of rock tunnel support
- 2019
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Ingår i: Tunnelling and Underground Space Technology. - : Elsevier. - 0886-7798 .- 1878-4364. ; 87, s. 15-26
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Tidskriftsartikel (refereegranskat)abstract
- A common support measure for underground excavations in jointed rock masses to support loose blocks is to apply a thin shotcrete layer to the periphery of the excavation and systematically install rockbolts into the surrounding rock mass. In this support system, large blocks are carried by the rockbolts and small blocks are carried by the thin shotcrete layer. To verify the shotcrete layer's load-bearing capacity and to stringently account for the large uncertainties incorporated in the variables involved in determining its capacity, analytical calculations in combination with reliability-based methods can be used. However, a lack of knowledge exists regarding the magnitude and uncertainty of shotcrete characteristics (thickness, adhesion, flexural tensile strength, residual flexural tensile strength, and compressive strength), making it difficult to apply reliability-based methods. A statistical quantification of these characteristics is therefore important to facilitate reliability-based methods in design and verification of shotcrete support. In this paper, we illustrate how shotcrete support against small loose blocks can be viewed as a correlated conditional structural system and how this system can be analyzed using reliability-based methods. In addition, we present a unique amount of data for the aforementioned variables, which are all incorporated in the design and verification of a shotcrete layer's ability to sustain loads from small loose blocks. Based on the presented data, we statistically quantify and propose suitable probability distributions for each variable. Lastly, we illustrate how the proposed probability distributions can be used in the design process to calculate the probability of exceeding the shotcrete's load-bearing capacity. Both the probabilistic quantification and the defined correlated conditional structural system along with the illustrative calculation example are followed by a discussion of their implications.
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| 22. |
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| 23. |
- Bjureland, William, et al.
(författare)
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Reliability aspects of rock tunnel design with the observational method
- 2017
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Ingår i: International Journal of Rock Mechanics And Mining Sciences. - : PERGAMON-ELSEVIER SCIENCE LTD. - 1365-1609 .- 1873-4545. ; 98, s. 102-110
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Tidskriftsartikel (refereegranskat)abstract
- According to Eurocode 7, two accepted approaches for managing uncertainty in tunnel design are reliability based methods and the observational method. Reliability-based methods account for uncertainty by acknowledging the random variation of the input parameters; the observational method does this by verifying the expected behavior from an initial design during the course of construction. However, in the framework of the observational method, as defined in Eurocode 7, no guidance is given on the selection of suitable parameters for observation and how they can be linked to the limits of acceptable behavior and, at a sufficiently early stage, the decision for implementing contingency actions. Furthermore, no guidance is given on how to verify that the structure fulfills society's required safety level. In this paper, we present a design procedure for shotcrete-supported rock tunnels that combines reliability-based methods with the observational method. The design procedure applies a deformation-based limit state function for the shotcrete support that is based on the convergence confinement method. We suggest how the requirements in the observational method, as defined in Eurocode 7, may be satisfied for this application. In particular, we focus on the structural reliability aspects. The structural reliability of the preliminary design is assessed with Monte Carlo simulations by calculating the expected deformations of the tunnel. The appropriateness of the preliminary design is then verified by observing the actual deformations during the course of construction. The observed deformations are used to predict the future behavior of the tunnel and to update the assessed probability of unsatisfactory behavior. If the defined deformation-based alarm limit regarding the structural reliability is exceeded, predefined contingency actions are put into operation. The procedure is illustrated with a shotcrete-lined circular rock tunnel and practical aspects in satisfying the reliability requirements with the observational method are discussed.
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| 24. |
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| 25. |
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| 26. |
- Chirumalla, Koteshwar, Associate Professor, et al.
(författare)
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Circular Business Models for the Electric Vehicle Battery Second Life : Navigating Battery Ecosystem Actors Towards Circularity
- 2024
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The electrification of vehicles has become a critical means to achieve climate-neutral transportation. As more electric vehicles (EV) are adopted, an increasing number of lithiumion batteries will be utilized, inevitably experiencing capacity degradation over time. Retaining the value of these retired batteries through remanufacturing, reusing, and repurposing to create a second life holds significant environmental and economic benefits. However, many companies within the battery ecosystem struggle to capitalize on this opportunity due to a lack of business insight and suitable business models tailored to their operational contexts.The ReCreate (Second Life Management of Electric Vehicle Batteries) research project was initiated to address these industrial needs through close collaboration with selected companies in the battery ecosystem. The project aims to define appropriate circular business models, methods, and processes to guide battery ecosystem actors in developing and implementing electric vehicle battery second life solutions, thereby advancing circularity around batteries and climate-neutral objectives. This handbook represents the culmination of three years of research within the ReCreate project. Its purpose is to present a simplified and practical overview of project outcomes across a series of key chapters. Comprising six chapters, the handbook will begin by discussing barriers and enablers, followed by circular business models and battery ecosystem management. It will then delve into design principles and performance monitoring guidelines, concluding with an integrated framework for second life and circular solutions for EV batteries. Each chapter briefly presents the main findings of the theme and concludes with discussion questions. The discussion questions include suggestions for relevant templates for workshops, and all templates are conveniently provided in the appendix for practical application. These templates serve as boundary objects, offering a starting point for internal and external cross-functional and cross-organizational dialogues within the electric vehicle battery ecosystem. They facilitate discussions and collaborations among various stakeholders, fostering alignment and synergy in developing circular business models for the second life of EV batteries. By facilitating reflection on current business strategies, needs, and pain points, the handbook aims to aid in the definition of future second life business strategies. We anticipate that this handbook will serve as a valuable resource for actors within the EV battery ecosystem, supporting their journey towards climate-neutral transportation.
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| 27. |
- Chirumalla, Koteshwar, Associate Professor, et al.
(författare)
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Configurations for second-life operations of electric vehicle batteries : A guiding framework for ecosystem management
- 2022
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Konferensbidrag (refereegranskat)abstract
- Firms need multi-stakeholder ecosystems to create successful second-life business models for electric vehicle (EV) batteries. However, there is a lack of guiding instrumentsto support the process of strategizing and managing the EV battery ecosystem for secondlife operations. The purpose of this study is to propose a guiding framework that could support firms in the EV battery ecosystem to establish and manage various configurations for second-life operations. The study developed a framework with four configuration phases—namely, firm-level initiation, ecosystem construction, firm-level optimization, and ecosystem orchestration. Based on these phases, the paper describes three configuration pathways to establish and manage second-life operations
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| 28. |
- Dahlquist, Erik, 1951-, et al.
(författare)
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Balancing Power in Sweden Using Different Renewable Resources, Varying Prices, and Storages Like Batteries in a Resilient Energy System
- 2023
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Ingår i: Energies. - 1996-1073. ; 16:12, s. 4734-4734
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, balancing electricity production using renewable energy such as wind power, PV cells, hydropower, and CHP (combined heat and power) with biomass is carried out in relation to electricity consumption in primarily one major region in Sweden, SE-3, which contains 75% of the country's population. The time perspective is hours and days. Statistics with respect to power production and consumption are analyzed and used as input for power-balance calculations. How long periods are with low or high production, as well as the energy for charge and discharge that is needed to maintain a generally constant power production, is analyzed. One conclusion is that if the difference in production were to be completely covered with battery capacity it would be expensive, but if a large part of the difference were met by a shifting load it would be possible to cover the rest with battery storage in an economical way. To enhance the economy with battery storage, second-life batteries are proposed to reduce the capital cost in particular. Batteries are compared to hydrogen as an energy carrier. The efficiency of a battery system is higher than that of hydrogen plus fuel cells, but in general much fewer precious materials are needed with an H-2/fuel-cell system than with batteries. The paper discusses how to make the energy system more robust and resilient.
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| 29. |
- Damasceno, Davi Rodrigues, et al.
(författare)
-
Effect of rock joints on lined rock caverns subjected to high internal gas pressure
- 2023
-
Ingår i: Journal of Rock Mechanics and Geotechnical Engineering. - : Elsevier BV. - 1674-7755. ; 15:7, s. 1625-1635
-
Tidskriftsartikel (refereegranskat)abstract
- The storage of hydrogen gas in lined rock caverns (LRCs) may enable the implementation of the first large-scale fossil-free steelmaking process in Sweden, but filling such storage causes joints in the rock mass to open, concentrating strains in the lining. The structural interaction between the LRC components must be able to reduce the strain concentration in the sealing steel lining; however, this interaction is complex and difficult to predict with analytical methods. In this paper, the strain concentration in LRCs from the opening of rock joints is studied using finite element (FE) analyses, where the large- and small-scale behaviors of the LRC are coupled. The model also includes concrete crack initiation and development with increasing gas pressure and rock joint width. The interaction between the jointed rock mass and the reinforced concrete, the sliding layer, and the steel lining is demonstrated. The results show that the rock mass quality and the spacing of the rock joints have the greatest influence on the strain distributions in the steel lining. The largest effect of rock joints on the maximum strains in the steel lining was observed for geological conditions of “good” quality rock masses.
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| 30. |
- Damasceno, Davi Rodrigues, et al.
(författare)
-
Reliability-based design methodology for lined rock cavern depth using the response surface method
- 2020
-
Ingår i: ISRM International Symposium - EUROCK 2020. - : International Society for Rock Mechanics.
-
Konferensbidrag (refereegranskat)abstract
- Efforts to decrease CO2 emissions in the Swedish steelmaking process involve the use of industrial quantities of hydrogen gas supplied from large-scale Lined Rock Cavern (LRC) storages in order to eliminate the use of fossil fuels. This storage must be placed at sufficient depth so that the overburden is able to resist the uplifting gas pressure from inside the cavern. Both the high reliability requirement and addressing the uncertainties related to the rock mass properties make it difficult to design for such structures. In this work, a reliability-based design methodology for the LRC depth specification using the Response surface (RS) method is presented. Geologic conditions of Sweden, i.e. hard rock, are considered and the analytical solution for the resistance to uplift includes the tensile strength of the failure surface in addition to the overburden weight pressure. The highest uncertainties are assumed to be related to the rock mass parameters and both the cavern radius and the maximum operational pressure are chosen to be the same as for the LRC in Skallen, in southwestern Sweden. Four random variables with varying correlation are used to estimate the acceptable cavern depth and the results are reasonable compared to previous experience. The efficiency of the RS method for the considered problem is observed both for required number of samples and accuracy, showing suitability to be used with more complex, difficult to evaluate, problems such as Finite Element models.
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| 31. |
- Damasceno, Davi Rodrigues, et al.
(författare)
-
Reliability-based design tool for gas storage in lined rock caverns
- 2024
-
Ingår i: Georisk. - : Informa UK Limited. - 1749-9518 .- 1749-9526. ; 18, s. 410-422
-
Tidskriftsartikel (refereegranskat)abstract
- The transition to a fossil-free energy matrix may require large quantities of hydrogen gas, which could be stored efficiently in an underground lined rock cavern (LRC). Since the consequences of failure can be catastrophic, the LRC design needs to have a small probability of failure. However, the current design practice for LRCs is deterministic, which limits the possibility to stringently address geotechnical uncertainties in the design. In this paper, a reliability-based design tool is presented for LRCs. The adaptive directional importance sampling (ADIS) method, which requires a relatively small number of samples, is used with a 3D finite element (FE) model to evaluate small probabilities of failure. An illustrative example based on the LRC in Skallen, southwestern Sweden, demonstrates the implementation and applicability of the developed design tool. The considered uncertainties are related to the geological conditions and the steel lining. The results show that the reliability of this LRC design meets the expected safety requirements. Considering different geological conditions with correlations, at least “good” quality rock mass is needed for the LRC design. An additional sensitivity analysis is performed to study the potential influence of corrosion and hydrogen embrittlement on the reduction of the LRC design reliability.
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| 32. |
- Damasceno, Davi Rodrigues, et al.
(författare)
-
Rock mass response for lined rock caverns subjected to high internal gas pressure
- 2023
-
Ingår i: Journal of Rock Mechanics and Geotechnical Engineering. - : Elsevier BV. - 1674-7755. ; 15:1, s. 119-129
-
Tidskriftsartikel (refereegranskat)abstract
- The storage of hydrogen gas in underground lined rock caverns (LRCs) enables the implementation of the first fossil-free steelmaking process to meet the large demand for crude steel. Predicting the response of rock mass is important to ensure that gas leakage due to rupture of the steel lining does not occur. Analytical and numerical models can be used to estimate the rock mass response to high internal pressure; however, the fitness of these models under different in situ stress conditions and cavern shapes has not been studied. In this paper, the suitability of analytical and numerical models to estimate the maximum cavern wall tangential strain under high internal pressure is studied. The analytical model is derived in detail and finite element (FE) models considering both two-dimensional (2D) and three-dimensional (3D) geometries are presented. These models are verified with field measurements from the LRC in Skallen, southwestern Sweden. The analytical model is inexpensive to implement and gives good results for isotropic in situ stress conditions and large cavern heights. For the case of anisotropic horizontal in situ stresses, as the conditions in Skallen, the 3D FE model is the best approach.
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| 33. |
- Egeskog, Johan, et al.
(författare)
-
Cyklisters utrymmesbehov : kunskapsunderlag till rekommendationer för utformning
- 2023
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Under hösten 2021 fick Transportstyrelsen i uppdrag av regeringen att analysera och vid behov lämna förslag till ändrade trafikregler för att andelen trafikanter som reser med cykel ska öka. Mot bakgrund av detta har Transportstyrelsen anlitat VTI, Statens väg- och transportforskningsinstitut för att bistå i arbetet genom att beskriva kunskapsläget utifrån gällande forskning.Syftet med uppdraget har främst varit att undersöka cyklisters utrymmesbehov i olika trafiksituationer och att ta fram underlag till rekommendationer för utformning av cykelinfrastrukturens bredder. Idag saknas regler eller gemensam byggpraxis för den fysiska utformningen av cykelfält och cykelbanor. Det är istället upp till respektive väghållare att ta fram sina egna typsektioner eller rekommendationer och kontrollera efterlevnaden.Resultaten i denna rapport baseras på litteraturstudier gällande utformningsstandarder och forskning kring cyklisters utrymmesbehov. Rekommendationer presenteras om minstabredder på cykelbanor och cykelfält beroende på möjlighet till möten och omkörningar, inkluderat dimensionering för lastcyklar, samt trygga avstånd till sidohinder. En ansats till modellstruktur för bedömning av utrymmesbehov vid högre flöden har även tagits fram.Cykelbanors bredd kan varieras beroende på den önskade dimensionerande trafiksituationen, det vill säga möjligheten att ett visst antal trafikanter ska kunna mötas eller köra om varandra säkert. Utifrån ett underhållsperspektiv är det dock fördelaktigt att anlägga cykelbanor med minst 2,5 meter bredd, oavsett trafiksituationen. Mindre bredd än så kan medföra lägre effektivitet för drift och underhåll med ökade livscykelkostnader som följd.
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| 34. |
- Egeskog, Johan, et al.
(författare)
-
Cyklisters utrymmesbehov : kunskapsunderlag till rekommendationer för utformning
- 2024
-
Ingår i: Sammanställning av referat från Transportforum 2024. - Linköping : Statens väg- och transportforskningsinstitut. ; , s. 474-475
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Under hösten 2021 fick Transportstyrelsen i uppdrag av regeringen att analysera och vid behov lämna förslag till ändrade trafikregler för att andelen trafikanter som reser med cykel ska öka. Mot bakgrund av detta anlitade Transportstyrelsen VTI, Statens väg- och transportforskningsinstitut för att bistå i arbetet genom att beskriva kunskapsläget utifrån gällande forskning. Historiskt har dimensionering för gång och cykel baserats på ingenjörsmässiga uppskattningar med lite eller inget empiriskt underlag. Syftet med uppdraget har främst varit att undersöka cyklisters utrymmesbehov i olika trafiksituationer och att ta fram underlag till rekommendationer för utformning av cykelinfrastrukturens bredder. Idag saknas regler eller gemensam byggpraxis för den fysiska utformningen av cykelfält och cykelbanor. Det är istället upp till respektive väghållare att ta fram sina egna typsektioner eller rekommendationer och kontrollera efterlevnaden. Inom ramen för detta arbete har det bland annat tagits fram grundläggande designriktlinjer som beaktar cyklister och lastcyklisters utrymmesbehov och interaktion med andra trafikanter. Resultaten i denna rapport baseras på litteraturstudier gällande utformningsstandarder och forskning kring cyklisters utrymmesbehov. Arbetets primära resultat består i framtagandet av minstabredder för cykelbanor och cykelfält beroende på möjlighet till möten och omkörningar, inkluderat dimensionering för lastcyklar, samt trygga avstånd till sidohinder. En enkelrikta cykelbana för vanliga cyklister bör inte understiga 0,95 m bredd, plus 0,35 meter fritt avstånd till sidohinder utanför cykelbanan på varje sida. En dubbelriktad cykelbana bör inte vara smalare än 2,15 m, plus 0,35 meter avstånd till sidohinder per sida. Vid fullt beaktande av lastcyklar blir cykelbanebredden 3,5 meter på dubbelriktade cykelbanor. En ansats till modellstruktur för bedömning av utrymmesbehov vid högre flöden har även tagits fram. Utöver de faktiska breddrekommendationerna så har även arbetet resulterat i framtagandet av en lista med utformningsparametrar för cyklisters utrymmesbehov. Dessa parametrar beskrivs med måttangivelse och nivå av empirisk uppbackning. Vissa av parametrarna saknar fortfarande empirisk uppbackning vilket synliggör behovet av fortsatta studier.
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| 35. |
- Eriksson, Henrik, 1973, et al.
(författare)
-
Effects of In-Company Quality Awards on Organizational Performance
- 2003
-
Ingår i: Total quality management (Print). - : Informa UK Limited. - 0954-4127 .- 1360-0613. ; 14:2, s. 235-242
-
Tidskriftsartikel (refereegranskat)abstract
- The relationship between total quality management (TQM) practices and improved performance has been frequently discussed in the literature. In this paper, the costs and the effects of in-company quality awards on performance are discussed and analysed. The paper covers a survey of Swedish companies that use or have used in-company quality awards to stimulate TQM efforts and thereby to improve performance. The study cannot show any strong evidence of improved performance for units that applied for the in-company quality award. However, in contrast to units that have not applied, some units that have applied for the in-company quality award considered that the results related to performance have improved greatly. One large positive effect perceived by the participating units was increased customer orientation while the largest costs were put on the description of activities and the improvement work itself.
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| 36. |
- Everard, A., et al.
(författare)
-
Microbiome of prebiotic-treated mice reveals novel targets involved in host response during obesity
- 2014
-
Ingår i: Isme Journal. - : Springer Science and Business Media LLC. - 1751-7362 .- 1751-7370. ; 8:10, s. 2116-2130
-
Tidskriftsartikel (refereegranskat)abstract
- The gut microbiota is involved in metabolic and immune disorders associated with obesity and type 2 diabetes. We previously demonstrated that prebiotic treatment may significantly improve host health by modulating bacterial species related to the improvement of gut endocrine, barrier and immune functions. An analysis of the gut metagenome is needed to determine which bacterial functions and taxa are responsible for beneficial microbiota-host interactions upon nutritional intervention. We subjected mice to prebiotic (Pre) treatment under physiological (control diet: CT) and pathological conditions (high-fat diet: HFD) for 8 weeks and investigated the production of intestinal antimicrobial peptides and the gut microbiome. HFD feeding significantly decreased the expression of regenerating islet-derived 3-gamma (Reg3g) and phospholipase A2 group-II (PLA2g2) in the jejunum. Prebiotic treatment increased Reg3g expression (by similar to 50-fold) and improved intestinal homeostasis as suggested by the increase in the expression of intectin, a key protein involved in intestinal epithelial cell turnover. Deep metagenomic sequencing analysis revealed that HFD and prebiotic treatment significantly affected the gut microbiome at different taxonomic levels. Functional analyses based on the occurrence of clusters of orthologous groups (COGs) of proteins also revealed distinct profiles for the HFD, Pre, HFD-Pre and CT groups. Finally, the gut microbiota modulations induced by prebiotics counteracted HFD-induced inflammation and related metabolic disorders. Thus, we identified novel putative taxa and metabolic functions that may contribute to the development of or protection against the metabolic alterations observed during HFD feeding and HFD-Pre feeding.
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| 37. |
- Friederich, Malou, 1983-, et al.
(författare)
-
Identification and distribution of uncoupling protein isoforms in the normal and diabetic rat kidney
- 2009
-
Ingår i: Advances in Experimental Medicine and Biology. - New York : Springer. - 0065-2598 .- 2214-8019. - 9780387859972 ; 645, s. 205-212
-
Tidskriftsartikel (refereegranskat)abstract
- Uncoupling protein (UCP)-2 and -3 are ubiquitously expressed throughout the body but there is currently no information regarding the expression and distribution of the different UCP isoforms in the kidney. Due to the known cross-reactivity of the antibodies presently available for detection of UCP-2 and -3 proteins, we measured the mRNA expression of UCP-1, -2 and -3 in the rat kidney in order to detect the kidney-specific UCP isoforms. Thereafter, we determined the intrarenal distribution of the detected UCP isoforms using immunohistochemistry. Thereafter, we compared the protein levels in control and streptozotocin-induced diabetic rats using Western blot. Expressions of the UCP isoforms were also performed in brown adipose tissue and heart as positive controls for UCP-1 and 3, respectively. UCP-2 mRNA was the only isoform detected in the kidney. UCP-2 protein expression in the kidney cortex was localized to proximal tubular cells, but not glomerulus or distal nephron. In the medulla, UCP-2 was localized to cells of the medullary thick ascending loop of Henle, but not to the vasculature or parts of the nephron located in the inner medulla. Western blot showed that diabetic kidneys have about 2.5-fold higher UCP-2 levels compared to controls. In conclusion, UCP-2 is the only isoform detectable in the kidney and UCP-2 protein can be detected in proximal tubular cells and cells of the medullary thick ascending loop of Henle. Furthermore, diabetic rats have increased UCP-2 levels compared to controls, but the mechanisms underlying this increase and its consequences warrants further studies.
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| 38. |
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| 39. |
- Greiner, Thomas U., 1977, et al.
(författare)
-
GLP-1R signaling modulates colonic energy metabolism, goblet cell number and survival in the absence of gut microbiota
- 2024
-
Ingår i: MOLECULAR METABOLISM. - 2212-8778. ; 83
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives: Gut microbiota increases energy availability through fermentation of dietary fibers to short-chain fatty acids in conventionally raised mice. Energy deficiency in germ-free (GF) mice increases glucagon-like peptide-1 (GLP-1) levels, which slows intestinal transit. To further analyze the role of GLP-1-mediated signaling in this model of energy deficiency, we re-derived mice lacking GLP-1 receptor (GLP-1R KO) as GF. Methods: GLP-1R KO mice were rederived as GF through hysterectomy and monitored for 30 weeks. Mice were subjected to rescue experiments either through feeding an energy-rich diet or colonization with a normal cecal microbiota. Histology and intestinal function were assessed at different ages. Intestinal organoids were assessed to investigate stemness. Results: Unexpectedly, 25% of GF GLP-1R KO mice died before 20 weeks of age, associated with enlarged ceca, increased cecal water content, increased colonic expression of apical ion transporters, reduced number of goblet cells and loss of colonic epithelial integrity. Colonocytes from GLP-1R KO mice were energy-deprived and exhibited increased ER-stress; mitochondrial fragmentation, increased oxygen levels and loss of stemness. Restoring colonic energy levels either by feeding a Western-style diet or colonization with a normal gut microbiota normalized gut phenotypes and prevented lethality. Conclusions: Our findings reveal a heretofore unrecognized role for GLP-1R signaling in the maintenance of colonic physiology and survival during energy deprivation.
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| 40. |
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| 41. |
- Hedberg, Jakob, et al.
(författare)
-
Randomized controlled trial of nasogastric tube use after esophagectomy : study protocol for the kinetic trial
- 2024
-
Ingår i: Diseases of the esophagus. - : John Wiley & Sons. - 1120-8694 .- 1442-2050. ; 37:6
-
Tidskriftsartikel (refereegranskat)abstract
- Esophagectomy is a complex and complication laden procedure. Despite centralization, variations in perioparative strategies reflect a paucity of evidence regarding optimal routines. The use of nasogastric (NG) tubes post esophagectomy is typically associated with significant discomfort for the patients. We hypothesize that immediate postoperative removal of the NG tube is non-inferior to current routines. All Nordic Upper Gastrointestinal Cancer centers were invited to participate in this open-label pragmatic randomized controlled trial (RCT). Inclusion criteria include resection for locally advanced esophageal cancer with gastric tube reconstruction. A pretrial survey was undertaken and was the foundation for a consensus process resulting in the Kinetic trial, an RCT allocating patients to either no use of a NG tube (intervention) or 5 days of postoperative NG tube use (control) with anastomotic leakage as primary endpoint. Secondary endpoints include pulmonary complications, overall complications, length of stay, health related quality of life. A sample size of 450 patients is planned (Kinetic trial: https://www.isrctn.com/ISRCTN39935085). Thirteen Nordic centers with a combined catchment area of 17 million inhabitants have entered the trial and ethical approval was granted in Sweden, Norway, Finland, and Denmark. All centers routinely use NG tube and all but one center use total or hybrid minimally invasive-surgical approach. Inclusion began in January 2022 and the first annual safety board assessment has deemed the trial safe and recommended continuation. We have launched the first adequately powered multi-center pragmatic controlled randomized clinical trial regarding NG tube use after esophagectomy with gastric conduit reconstruction.
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| 42. |
- Hellgren, Rikard, 1988-, et al.
(författare)
-
Measurement of ice pressure on a concrete dam with a prototype ice load panel
- 2020
-
Ingår i: Cold Regions Science and Technology. - : Elsevier. - 0165-232X .- 1872-7441. ; 170
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents the development and installation of a prototype ice load panel and measurements of ice load from February 2016 to February 2018 at the Rätan hydropower dam in Sweden. The design of the 1 × 3 m2 panel enables direct measurement of ice pressure on the concrete surface is based on previous experience from similar measurements with sea ice. Important features of the design are sufficient height and width to reduce scale effects and to cover the ice thickness and variations in water level. The Rätan dam was chosen based on several criteria so that the ice load is considered to be reasonably idealized against the dam structure.For the three winters 2016, 2016/2017, 2017/2018, the maximum ice load recorded was 161 kN/m, 164 kN/m and 61 kN/m respectively. There were significant daily fluctuations during the cold winter months, and the daily peak ice loads showed a visual correlation with the daily average temperature and with the daily pattern of operation of the power station with its corresponding water level variations.
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| 43. |
- Hellgren, Rikard, 1988-, et al.
(författare)
-
Measurement of ice pressure on a concrete dam with aprototype ice load panel
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- This paper presents the development and installation of a prototype ice load panel andmeasurements of ice load from February 2016 to February 2018 at the Rätan hydropower damin Sweden. The design of the 1x3 m2 panel enabling direct measurement of ice pressure on theconcrete surface is based on previous experience from similar measurements with sea ice.Important features of the design are sufficient height and width to reduce scale effects and tocover the ice thickness and variations in water level. The Rätan dam was chosen based onseveral criteria so that the ice load is considered to be reasonably idealized against the damstructure.For the three winters 2016, 2016/2017, 2017/2018, the maximum ice load recorded was 161kN/m, 164 kN/m and 61 kN/m respectively. There were significant daily fluctuations duringthe cold winter months, and the daily peak ice loads showed a visual correlation with the dailyaverage temperature and with the daily pattern of operation of the power station with itscorresponding water level variations
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| 44. |
- Hellgren, Rikard, 1988-, et al.
(författare)
-
Pull-out tests of 50-year old rock bolts
- 2016
-
Ingår i: Proceedings of the International Symposium on Appropriate technology to ensure proper Development, Operation and Maintenance of Dams in Developing Countries. - Johannesburg. - 9780620710428 ; , s. 263-272
-
Konferensbidrag (refereegranskat)abstract
- In this paper, detailed numerical and analytical calculations are presented with the aim to study the effect of rock bolts and the influence of degradation on the dam safety. In addition, results from inspections and pull-out tests are presented from a case study with rock bolts that has been installed for 50 years. All tested bolts have with margin withstood higher stresses than the maximum allowed stresses according to Swedish standards. At visual inspection, no bolts have shown any major signs of degradation and all investigate bolts are in very good condition.
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| 45. |
- Hoeft, Madeleine, et al.
(författare)
-
Construction Automation and Robotics in Infrastructure
- 2022
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In Sweden, as in many other countries, the construction andinfrastructure sector are of large and growing importance for the economyand society. For instance, the construction industry’s turnover equals 11% ofthe Swedish gross domestic product (GDP) (Byggföretagen 2021), and theSwedish Transport Administration plans to invest SEK 799 billion during theperiod 2022-2033 (Regeringen 2021). At the same time, the cost ofinfrastructure projects has increased more than the consumer price index(CPI) (Trafikverket (2021)), partly due to a poorer development of theproductivity compared to other industries. An improved productivity andefficiency in the transport infrastructure and construction industry istherefore necessary. One way to increase productivity, improve theoccupational health and safety, and sustainability is through automation anddigitalization of the construction industry.The aim of the present report has been to identify ongoing initiatives andexisting research trends in construction automation with a focus on civilengineering, both nationally and internationally; and to identify potentialsand challenges that exist for the development of construction automation.Furthermore, the prerequisites for the implementation of automation in theconstruction industry have been studied. The research questions were studiedthrough a literature study and two thematic days on the subject.The results from the literature study shows that a clear increasing trendexists, both nationally and internationally, in automation, digitization androbotisation in the construction industry. The same trend can also be seen incivil engineering for roads, bridges, tunnels, as well as in the mining industry.With the mining industry as a role model, construction companies,universities, suppliers and clients together with small and medium-sizedenterprises (SMEs) should come together to develop a common vision and astrategic roadmap to enforce automation and digitization of the constructionindustry. A development of both technical, organizational and financialstructures is required, where an attractive business ecosystem can bedeveloped, enabling the upscaling of construction automation.Interdisciplinary collaborations, test-beds at an early stage, competencedevelopment, new financing infrastructure and a common vision are crucialto create conditions for construction automation.
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| 46. |
- Isaksson, Johan, et al.
(författare)
-
KRAS G12C mutant non-small cell lung cancer linked to female sex and high risk of CNS metastasis : Population-based demographics and survival data from the National Swedish Lung Cancer Registry
- 2023
-
Ingår i: Clinical Lung Cancer. - : Elsevier. - 1525-7304 .- 1938-0690. ; 24:6, s. 507-518
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundReal-world data on demographics related to KRAS mutation subtypes are crucial as targeted drugs against the p.G12C variant have been approved.MethodWe identified 6183 NSCLC patients with reported NGS-based KRAS status in the Swedish national lung cancer registry between 2016 and 2019. Following exclusion of other targetable drivers, three cohorts were studied: KRAS-G12C (n = 848), KRAS-other (n = 1161), and driver negative KRAS-wild-type (wt) (n = 3349).ResultsThe prevalence of KRAS mutations and the p.G12C variant respectively was 38%/16% in adenocarcinoma, 28%/13% in NSCLC-NOS and 6%/2% in squamous cell carcinoma. Women were enriched in the KRAS-G12C (65%) and KRAS-other (59%) cohorts versus KRAS-wt (48%). A high proportion of KRAS-G12C patients in stage IV (28%) presented with CNS metastasis (vs. KRAS-other [19%] and KRAS-wt [18%]). No difference in survival between the mutation cohorts was seen in stage I-IIIA. In stage IV, median overall survival (mOS) from date of diagnosis was shorter for KRAS-G12C and KRAS-other (5.8 months/5.2 months) vs. KRAS wt (6.4 months). Women had better outcome in the stage IV cohorts, except in KRAS-G12C subgroup where mOS was similar between men and women. Notably, CNS metastasis did not impact survival in stage IV KRAS-G12C, but was associated with poorer survival, as expected, in KRAS-other and KRAS-wt.ConclusionThe KRAS p.G12C variant is a prevalent targetable driver in Sweden and significantly associated with female sex and presence of CNS metastasis. We show novel survival effects linked to KRAS p.G12C mutations in these subgroups with implications for clinical practice.
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| 47. |
- Ivars, Diego Mas, 1974-, et al.
(författare)
-
A case study of the Odenplan station in the Stockholm City Link project - Analysis of in situ stresses and observed ground behaviour.
- 2016
-
Rapport (refereegranskat)abstract
- The Odenplan Station in the Stockholm City Link project is located directly under theexisting subway station with a minimum rock cover of approximately 7 m. The span of theOdenplan Station is 25 m. When the Odenplan station was excavated, deformations largerthan anticipated in previous calculations were observed. The main reason for this discrepancyis believed to be high horizontal in situ and/or persistent fractures in the area parallel withthe excavation.The excavation of the Odenplan station constitutes a case study with well-documented rockmass characteristics, excavation sequences, support sequences and measured deformations.It therefore provides a unique project to analyse. Based on this case study, the main objectivesof this study was to (1) suggest a general technique for numerical back analyses based onmeasured deformations under geological conditions as those present in the Stockholm area,and (2) analyse the range of possible in situ stresses at Odenplan Station in the City Linkproject.The complex three-dimensional 3DEC model lead to rather long computational times. Ageneral technique for a real back analysis was therefore not possible to obtain in this study,since it would require unrealistically long computational time. Instead, a sensitivity study onthe in situ stresses and different types of continuum and discontinuum approaches wereperformed. The results from the analyses gave valuable insight into which types of modelsthat were able to properly recreate the observed ground behavior at Odenplan. The resultsfrom the study clearly showed that a continuum approach does not capture the true behaviorof the blocky rock mass at Odenplan. It is therefore recommended that discontinuumapproaches are used in the future when structurally controlled block movements could beexpected. However, the exact cause behind the discrepancy between the continuum and thediscontinuum model has not been determined in this report.The performed sensitivity analysis suggests that the in situ stresses are high and in the rangeof those previously measured. Maximum horizontal in situ stresses are probably in the rangeof 5.7-7.2 MPa at a depth of 0-20 m, which agrees well with the results of previous rockstress measurements, which were, on average, 8.1 MPa at a depth of 30 m.The encouraging results from this project indicate that further stress sensitivity analysesshould be performed to have a better estimation of the range of in situ stresses in theStockholm area by fitting displacements obtained from modeling to those measured in situ in different projects. These analyses are important in order to understand our present abilityto perform numerical simulations reflecting true rock mass behavior.
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| 48. |
- Jacobsson, Lars, et al.
(författare)
-
Experimental program on mechanical properties of large rock fractures
- 2021
-
Ingår i: IOP Conference Series. - : IOP Publishing. ; , s. 012015-
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Konferensbidrag (refereegranskat)abstract
- Predictions of fracture displacements are required to support the safety assessments of a deep geological repository for nuclear spent fuel. Laboratory and in-situ experiments are used to estimate these properties. Despite significant contributions in the last decades, there is a knowledge gap in terms of the impact of high normal stresses on the mechanical properties of large-scale fractures under Constant Normal Stiffness (CNS) boundary conditions. Within the framework of the POST project, a cooperative effort was made by SKB (Sweden), NWMO (Canada), and Posiva from Finland (in phase 1) to study these questions. In the second phase of the POST project, a first of a kind direct shear testing machine was manufactured and calibrated that can accommodate samples up to 400 × 600 mm under normal stresses up to 10 MPa, for both CNS and Constant Normal Load (CNL) conditions, with the ability to shear the sample up to 50 mm. Several best practice procedures were developed for fracture characterization pre-, syn-, and post-shear test which utilize high resolution optical scanning, contact pressure measurements, Digital Image Correlation (DIC) measurements, and acoustic emission measurements during the shear test. Natural and tensile-induced fractures of a granitic rock as well as replicas of the hard rock fractures, at three different fracture sizes of 35×60 mm, 70×100 mm, and 300×500 mm, are now being tested. It is hoped that this program will provide a set of high-quality data which will help reduce the knowledge gap in the understanding of fracture behavior.
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| 49. |
- Jakobsson, Hedvig E, et al.
(författare)
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The composition of the gut microbiota shapes the colon mucus barrier.
- 2015
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Ingår i: EMBO reports. - : EMBO. - 1469-3178 .- 1469-221X. ; 16, s. 164-177
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Tidskriftsartikel (refereegranskat)abstract
- Two C57BL/6 mice colonies maintained in two rooms of the same specific pathogen-free (SPF) facility were found to have different gut microbiota and a mucus phenotype that was specific for each colony. The thickness and growth of the colon mucus were similar in the two colonies. However, one colony had mucus that was impenetrable to bacteria or beads the size of bacteria-which is comparable to what we observed in free-living wild mice-whereas the other colony had an inner mucus layer penetrable to bacteria and beads. The different properties of the mucus depended on the microbiota, as they were transmissible by transfer of caecal microbiota to germ-free mice. Mice with an impenetrable mucus layer had increased amounts of Erysipelotrichi, whereas mice with a penetrable mucus layer had higher levels of Proteobacteria and TM7 bacteria in the distal colon mucus. Thus, our study shows that bacteria and their community structure affect mucus barrier properties in ways that can have implications for health and disease. It also highlights that genetically identical animals housed in the same facility can have rather distinct microbiotas and barrier structures.
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| 50. |
- Johansson, Anna, et al.
(författare)
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A non-fatal intoxication and seven deaths involving the dissociative drug 3-MeO-PCP
- 2017
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Ingår i: Forensic Science International. - : ELSEVIER IRELAND LTD. - 0379-0738 .- 1872-6283. ; 275, s. 76-82
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: 3-methoxyphencyclidine (3-MeO-PCP) appeared on the illicit drug market in 2011 and is an analogue of phencyclidine, which exhibits anesthetic, analgesic and hallucinogenic properties. In this paper, we report data from a non-fatal intoxication and seven deaths involving 3-MeO-PCP in Sweden during the period March 2014 until June 2016. Case descriptions: The non-fatal intoxication case, a 19-year-old male with drug problems and a medical history of depression, was found awake but tachycardic, hypertensive, tachypnoeic and catatonic at home. After being hospitalized, his condition worsened as he developed a fever and lactic acidosis concomitant with psychomotor agitation and hallucinations. After 22 h of intensive care, the patient had made a complete recovery. During his hospitalization, a total of four blood samples were collected at different time points. The seven autopsy cases, six males and one female, were all in their twenties to thirties with psychiatric problems and/or an ongoing drug abuse. Methods: 3-MeO-PCP was identified with liquid chromatography (LC)/time-of-flight technology and quantified using LC-tandem mass spectrometry. Results: In the clinical case, the concentration of 3-MeO-PCP was 0.14 mu g/g at admission, 0.08 mu g/g 2.5 h after admission, 0.06 mu g/g 5 h after admission and 0.04 mu g/g 17 h after admission. The half-life of 3-MeO-PCP was estimated to 11 h. In the autopsy cases, femoral blood concentrations ranged from 0.05 mu g/g to 0.38 mu g/g. 3-MeO-PCP was the sole finding in the case with the highest concentration and the cause of death was established as intoxication with 3-MeO-PCP. In the remaining six autopsy cases, other medications and drugs of abuse were present as well. Conclusion: Despite being scheduled in January 2015, 3-MeO-PCP continues to be abused in Sweden. Exposure to 3-MeO-PCP may cause severe adverse events and even death, especially if the user does not receive life-supporting treatment.
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