| 1. |
- Edin, Carl, et al.
(författare)
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Ectopic fat is associated with cardiac remodeling - A comprehensive assessment of regional fat depots in type 2 diabetes using multi-parametric MRI.
- 2022
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Ingår i: Frontiers in Cardiovascular Medicine. - : Frontiers Media SA. - 2297-055X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Background: Different regional depots of fat have distinct metabolic properties and may relate differently to adverse cardiac remodeling. We sought to quantify regional depots of body fat and to investigate their relationship to cardiac structure and function in Type 2 Diabetes (T2D) and controls.Methods: From the SCAPIS cohort in Linköping, Sweden, we recruited 92 subjects (35% female, mean age 59.5 ± 4.6 years): 46 with T2D and 46 matched controls. In addition to the core SCAPIS data collection, participants underwent a comprehensive magnetic resonance imaging examination at 1.5 T for assessment of left ventricular (LV) structure and function (end-diastolic volume, mass, concentricity, ejection fraction), as well as regional body composition (liver proton density fat fraction, visceral adipose tissue, abdominal subcutaneous adipose tissue, thigh muscle fat infiltration, fat tissue-free thigh muscle volume and epicardial adipose tissue).Results: Compared to the control group, the T2D group had increased: visceral adipose tissue volume index (P < 0.001), liver fat percentage (P < 0.001), thigh muscle fat infiltration percentage (P = 0.02), LV concentricity (P < 0.001) and LV E/e'-ratio (P < 0.001). In a multiple linear regression analysis, a negative association between liver fat percentage and LV mass (St Beta -0.23, P < 0.05) as well as LV end-diastolic volume (St Beta -0.27, P < 0.05) was found. Epicardial adipose tissue volume and abdominal subcutaneous adipose tissue volume index were the only parameters of fat associated with LV diastolic dysfunction (E/e'-ratio) (St Beta 0.24, P < 0.05; St Beta 0.34, P < 0.01, respectively). In a multivariate logistic regression analysis, only visceral adipose tissue volume index was significantly associated with T2D, with an odds ratio for T2D of 3.01 (95% CI 1.28-7.05, P < 0.05) per L/m2 increase in visceral adipose tissue volume.Conclusions: Ectopic fat is predominantly associated with cardiac remodeling, independently of type 2 diabetes. Intriguingly, liver fat appears to be related to LV structure independently of VAT, while epicardial fat is linked to impaired LV diastolic function. Visceral fat is associated with T2D independently of liver fat and abdominal subcutaneous adipose tissue.
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| 2. |
- Edin, Carl, et al.
(författare)
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Liver fibrosis is associated with left ventricular remodeling : insight into the liver-heart axis
- 2024
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Ingår i: European Radiology. - : Springer Science and Business Media LLC. - 0938-7994 .- 1432-1084.
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Tidskriftsartikel (refereegranskat)abstract
- Objective: In non-alcoholic fatty liver disease (NAFLD), liver fibrosis is the strongest predictor of adverse outcomes. We sought to investigate the relationship between liver fibrosis and cardiac remodeling in participants from the general population using magnetic resonance imaging (MRI), as well as explore potential mechanistic pathways by analyzing circulating cardiovascular biomarkers.Methods: In this cross-sectional study, we prospectively included participants with type 2 diabetes and individually matched controls from the SCAPIS (Swedish CArdioPulmonary bioImage Study) cohort in Linköping, Sweden. Between November 2017 and July 2018, participants underwent MRI at 1.5 Tesla for quantification of liver proton density fat fraction (spectroscopy), liver fibrosis (stiffness from elastography), left ventricular (LV) structure and function, as well as myocardial native T1 mapping. We analyzed 278 circulating cardiovascular biomarkers using a Bayesian statistica lapproach.Results: In total, 92 participants were enrolled (mean age 59.5 ± 4.6 years, 32 women). The mean liver stiffness was 2.1 ± 0.4 kPa. 53 participants displayed hepatic steatosis. LV concentricity increased across quartiles of liver stiffness. Neither liver fat nor liver stiffness displayed any relationships to myocardial tissue characteristics (native T1). In a regression analysis, liver stiffness was related to increased LV concentricity. This association was independent of diabetes and liver fat (Beta = 0.26, p = 0.0053), but was attenuated (Beta = 0.17, p = 0.077) when also adjusting for circulating levels of interleukin-1 receptor type 2.Conclusion: MRI reveals that liver fibrosis is associated to structural LV remodeling, in terms of increased concentricity, in participants from the general population. This relationship could involve the interleukin-1 signaling.
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| 3. |
- Holmberg, Jonas, 1976-, et al.
(författare)
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Machining of additively manufactured alloy 718 in as-built and heat-treated condition: surface integrity and cutting tool wear
- 2024
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Ingår i: The International Journal of Advanced Manufacturing Technology. - : Springer Nature. - 0268-3768 .- 1433-3015. ; 130:3-4, s. 1823-1842
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Tidskriftsartikel (refereegranskat)abstract
- Additive manufacturing (AM) using powder bed fusion is becoming a mature technology that offers great possibilities and design freedom for manufacturing of near net shape components. However, for many gas turbine and aerospace applications, machining is still required, which motivates further research on the machinability and work piece integrity of additive-manufactured superalloys. In this work, turning tests have been performed on components made with both Powder Bed Fusion for Laser Beam (PBF-LB) and Electron Beam (PBF-EB) in as-built and heat-treated conditions. The two AM processes and the respective heat-treatments have generated different microstructural features that have a great impact on both the tool wear and the work piece surface integrity. The results show that the PBF-EB components have relatively lower geometrical accuracy, a rough surface topography, a coarse microstructure with hard precipitates and low residual stresses after printing. Turning of the PBF-EB material results in high cutting tool wear, which induces moderate tensile surface stresses that are balanced by deep compressive stresses and a superficial deformed surface that is greater for the heat-treated material. In comparison, the PBF-LB components have a higher geometrical accuracy, a relatively smooth topography and a fine microstructure, but with high tensile stresses after printing. Machining of PBF-LB material resulted in higher tool wear for the heat-treated material, increase of 49%, and significantly higher tensile surface stresses followed by shallower compressive stresses below the surface compared to the PBF-EB materials, but with no superficially deformed surface. It is further observed an 87% higher tool wear for PBF-EB in as-built condition and 43% in the heat-treated condition compared to the PBF-LB material. These results show that the selection of cutting tools and cutting settings are critical, which requires the development of suitable machining parameters that are designed for the microstructure of the material.
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| 4. |
- 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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| 5. |
- 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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| 6. |
- Hogmalm, Johan, 1979, et al.
(författare)
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In situ Rb-Sr and K-Ca dating by LA-ICP-MS/MS: an evaluation of N2O and SF6 as reaction gases
- 2017
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Ingår i: Journal of Analytical Atomic Spectrometry. - : Royal Society of Chemistry (RSC). - 0267-9477 .- 1364-5544. ; 32:2, s. 305-313
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Tidskriftsartikel (refereegranskat)abstract
- In situ dating of K-rich minerals, e.g. micas and K-feldspar, by the Rb–Sr isotopic system is a new development made possible by the ICP-MS/MS technique. Online chemical separation of Rb and Sr is possible in an O2-filled reaction cell, wherein a portion of the Sr reacts to SrO+ while simultaneously no RbO+ is formed. O2 reactions provide stable analytical conditions sufficient for precise and accurate determination of Rb/Sr and Sr/Sr isotopic ratios using 80 micron laser ablation spots. However, to date <10% of the Sr reacts with O2 as reaction gas, leaving room for improvement using more potent reaction gases. With a more efficient reactive transfer, it should be possible to obtain similar results with a smaller laser spot size, hence gaining higher spatial resolution. In this study, we have evaluated N2O and SF6 as reaction gases since they have previously been shown to react strongly with Sr+, without affecting Rb+. Analytical conditions, including cell parameters and reaction gas flow rate were optimized while ablating NIST SRM 610. The main reaction product is SrO+ for N2O reaction and SrF+ for SF6 reaction. Both gases show significantly higher reaction product formation compared to O2 with >85% of Sr reacting with N2O and >70% Sr reacting with SF6; Rb does not react with either gas. As a result, the sensitivity for Sr reaction products is ∼10 times higher with N2O and ∼8 times higher with SF6 compared to O2. With these more reactive gases, the error of mica isochron ages, calibrated against a newly developed nano-particulate pressed powder tablet of mica–Mg, is ∼1% using a 50 μm laser spot. Our tests show that both N2O and SF6 form interfering reaction products, e.g., SrOH (N2O), SiF3 and TiF3 (SF6) that are difficult to handle using single mass spectrometer instruments, but which can be overcome using MS/MS. Using SF6 combined with H2, it is possible to measure 40Ca+ as 40Ca19F+, free from interference of 40Ar+ and 40K+. This facilitates the dating of micas by the K–Ca isotopic system; we present the first in situ K–Ca age determination.
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| 7. |
- Johansson, Dan, 1964-, et al.
(författare)
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Family business : A missing link in economics?
- 2020
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Ingår i: The Journal of Family Business Strategy. - : Elsevier. - 1877-8585 .- 1877-8593. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Family firms account for a substantial share of economic activity and deviate from standard economic assumptions on firmbehavior. However, little is known about how these firms are represented in economic theory. This article examines the inclusion of family business in the curricula of economics doctoral programs in the United States and Sweden as well as professors’ and textbook authors’ views and research on family business. Textbooks, articles and course offerings used in doctoral programs are considered to indicate the state of established knowledge in the field. The findings show that family business is not included in the examined curricula. Furthermore, professors and authors do not publish research on family business and generally do not see a need to incorporate it into economic theory. This article concludes that family business is excluded from ‘core’ economic theory due to a lack of paradigmatic pluralism, axiomatic incompatibility, path dependency, institutional bias and data constraints. Lastly, it is speculated that integration of family business theory into standard economic modeling is likely to occur outside prestigious universities due to path dependency in research.
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| 8. |
- Johansson, Jessika, 1990, et al.
(författare)
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Phagocyte interactions with Mycobacterium tuberculosis - Simultaneous analysis of phagocytosis, phagosome maturation and intracellular replication by imaging flow cytometry.
- 2015
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Ingår i: Journal of immunological methods. - : Elsevier BV. - 1872-7905 .- 0022-1759. ; 427, s. 73-84
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Tidskriftsartikel (refereegranskat)abstract
- Utilization of compounds that enhance the innate immune response against Mycobacterium tuberculosis is an attractive strategy for combating tuberculosis in the post-antibiotic era. Thus, it is crucial to develop methods that can be used to screen for such compounds and to investigate their mechanisms of action. Here, we used imaging flow cytometry (ImageStreamX Mk II), which enables rapid quantification of microscopic images in flow, to study the interaction between phagocytes and M. tuberculosis. Macrophage-differentiated THP-1 cells were infected with GFP-expressing M. tuberculosis H37Ra, and methods for rapidly assessing phagocytosis, phagosome maturation, and bacterial replication inside the cells were developed and evaluated. These aspects of innate immunity are essential in determining the outcome of mycobacterial infection of phagocytes. The technique was found effective for monitoring phagocytosis of mycobacteria, phagosomal acidification and phagolysosomal fusion, as well as for measuring mycobacterial replication inside the cells. Several of these aspects could be analyzed simultaneously in the same sample, providing a great deal of information about the phagocyte–mycobacterial interaction at once. Thus, this method has great potential to be useful both for basic research questions and for evaluating compounds that enhance the innate immune response against M. tuberculosis.
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| 9. |
- Karlsson, Johan, 1990-
(författare)
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Does Regional Context Matter for Family Firm Employment Growth?
- 2018
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Ingår i: The Journal of Family Business Strategy. - : Elsevier. - 1877-8585 .- 1877-8593. ; 9:4, s. 293-310
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Tidskriftsartikel (refereegranskat)abstract
- This study investigates the proposition that family firms have comparative employment growth advantages in relation to non-family firms in regions with relatively low population density. This premise is tested across metropolitan, urban and rural regions using total population data on domestically and privately owned, single-plant, non-listed limited liability firms in Sweden. A panel of more than 89,000 firms is followed over a seven-year period from 2004 to 2010. The average family firm is found to grow more slowly than the average non-family firm across the urban-rural context. However, in line with the study’s conjecture, these differences are found to decrease across metropolitan, urban and rural regions.
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| 10. |
- Karlsson, Johan, 1990-
(författare)
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Essays on Family Firms and Firm Growth Barriers
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis concerns the implications of family ownership and perceived growth barriers for firm decision-making and performance. The first article examines the inclusion of family business in economics doctoral programs in the United States and Sweden, as well as the views of professors and textbook authors and research on family business. It is found that family business is not included in the examined curricula. Furthermore, professors and authors do not publish research on family business and generally do not see a need to incorporate it into economic theory. The article concludes by discussing the causes of this omission, as well as strategies to overcome them in order to further our understanding of economic action. The second article presents a novel strategy for identifying domiciled family firms using total population data. By applying this strategy to Swedish data, family firms are found to contribute to one-third of Swedish employment and gross domestic product, and a significant share of Sweden’s largest firms are family-owned. In general, family firms are found to be smaller than their non-family equivalents, although they are more profitable. Meanwhile, differences between family firms and nonfamily firms are found to diminish with firm size. The third article examines whether family firms have a comparative employment growth advantage over nonfamily firms in regions with relatively low population density. As a group, family firms are found to be the main source of job creation in rural regions, largely as a result of their large numbers. Nevertheless, the average family firm is found to grow more slowly than the average non-family firm. Meanwhile, in line with the study’s conjecture, this difference is found to decrease across the urban-rural context, i.e., across metropolitan, urban and rural regions. The fourth paper examines the representation of women in top management teams1 in family firms and non-family firms. Moreover, the share of women in a firm’s top management team is found to be positively associated with the additional appointment of female managers. Lastly, kinship bonds between the owning families and prospective managers are found to be positively associated with the appointment of women on top management teams. The fifth paper aims to capture the relationship between perceived growth barriers and firm size, which is achieved by developing a novel data-driven strategy for identifying firm size groups. It is found that smaller firms typically face accessibility constraints on equity financing, whereas larger firms generally face barriers related to competition and accessibility to qualified staff. These results are benchmarked against those using prevailing strategies for measuring firm size, whereby it is suggested that there may be a need for methodological rethinking in the field regarding its treatment of firm size.
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| 11. |
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| 12. |
- Karlsson, Johan, 1990-
(författare)
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Firm size and growth barriers : a data-driven approach
- 2021
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Ingår i: Small Business Economics. - : Springer. - 0921-898X .- 1573-0913. ; 57:3, s. 1319-1338
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Tidskriftsartikel (refereegranskat)abstract
- This article aims to capture the relationship between perceived growth barriers and firm size. This aim is pursued by developing a novel data-driven identification strategy that assigns firm size groups based on their statistical relationships to perceived growth barriers. The analysis is undertaken using data for approximately 44,000 Swedish SMEs (0-249 employees) for 2011, 2014, and 2017. The results suggest that small firms typically face constraints on equity financing, whereas larger firms face barriers regarding competition and recruitment. As a benchmark, the performance of the developed method is compared with prevailing strategies that use ad hoc firm size groups. The findings show that ad hoc groups fail to accurately capture size thresholds at which firms incur barriers, and they yield a consistently lower model fit compared with the method proposed here. Consequently, there may be a need for methodological rethink in the field regarding the treatment of firm size.
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| 13. |
- Larsson, Johan, 1990-, et al.
(författare)
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Combining endocannabinoids with retigabine for enhanced M-channel effect and improved KV7 subtype selectivity
- 2020
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Ingår i: The Journal of General Physiology. - : ROCKEFELLER UNIV PRESS. - 0022-1295 .- 1540-7748. ; 152:8
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Tidskriftsartikel (refereegranskat)abstract
- Retigabine is unique among anticonvulsant drugs by targeting the neuronal M-channel, which is composed of KV7.2/KV7.3 and contributes to the negative neuronal resting membrane potential. Unfortunately, retigabine causes adverse effects, which limits its clinical use. Adverse effects may be reduced by developing M-channel activators with improved KV7 subtype selectivity. The aim of this study was to evaluate the prospect of endocannabinoids as M-channel activators, either in isolation or combined with retigabine. Human KV7 channels were expressed in Xenopus laevis oocytes. The effect of extracellular application of compounds with different properties was studied using two-electrode voltage clamp electrophysiology. Site-directed mutagenesis was used to construct channels with mutated residues to aid in the mechanistic understanding of these effects. We find that arachidonoyl-L-serine (ARA-S), a weak endocannabinoid, potently activates the human M-channel expressed in Xenopus oocytes. Importantly, we show that ARA-S activates the M-channel via a different mechanism and displays a different KV7 subtype selectivity compared with retigabine. We demonstrate that coapplication of ARA-S and retigabine at low concentrations retains the effect on the M-channel while limiting effects on other KV7 subtypes. Our findings suggest that improved KV7 subtype selectivity of M-channel activators can be achieved through strategically combining compounds with different subtype selectivity.
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| 14. |
- Lehtveer, Mariliis, 1983, et al.
(författare)
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Actuating the European Energy System Transition: Indicators for Translating Energy Systems Modelling Results into Policy-Making
- 2021
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Ingår i: Frontiers in Energy Research. - : Frontiers Media SA. - 2296-598X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we define indicators, with a focus on the electricity sector, that translate the results of energy systems modelling to quantitative entities that can facilitate assessments of the transitions required to meet stringent climate targets. Such indicators, which are often overlooked in model scenario presentations, can be applied to make the modelling results more accessible and are useful for managing the transition on the policy level, as well as for internal evaluations of modelling results. We propose a set of 13 indicators related to: 1) the resource and material usages in modelled energy system designs; 2) the rates of transition from current to future energy systems; and 3) the energy security in energy system modelling results. To illustrate its value, the proposed set of indicators is applied to energy system scenarios derived from an electricity system investment model for Northern Europe. We show that the proposed indicators are useful for facilitating discussions, raising new questions, and relating the modelling results to Sustainable Development Goals and thus facilitate better policy processes. The indicators presented here should not be seen as a complete set, but rather as examples. Therefore, this paper represents a starting point and a call to other modellers to expand and refine the list of indicators.
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| 15. |
- Qvick, Alvida, 1990-, et al.
(författare)
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Liquid biopsy as an option for predictive testing and prognosis in patients with lung cancer
- 2021
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Ingår i: Molecular Medicine. - : Springer. - 1076-1551 .- 1528-3658. ; 27:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The aim of this study was to investigate the clinical value of liquid biopsy as a primary source for variant analysis in lung cancer. In addition, we sought to characterize liquid biopsy variants and to correlate mutational load to clinical data.Methods: Circulating cell-free DNA was extracted from plasma from patients with lung cancer (n = 60) and controls with benign lung disease (n = 16). Variant analysis was performed using the AVENIO ctDNA Surveillance kit and the results were correlated to clinical and variant analysis data from tumor tissue or cytology retrieved from clinical routine diagnostics.Results: There were significantly more variants detected in lung cancer cases compared to controls (p = 0.011), but no difference between the histological subgroups of lung cancer was found (p = 0.465). Furthermore, significantly more variants were detected in patients with stage IIIb-IV disease compared to patients with stage I-IIIa (median 7 vs 4, p = 0.017). Plasma cfDNA mutational load was significantly associated with overall survival (p = 0.010). The association persisted when adjusted for stage and ECOG performance status (HR: 3.64, 95% CI 1.37-9.67, p = 0.009). Agreement between tumor and plasma samples significantly differed with stage; patients with stage IIIb-IV disease showed agreement in 88.2% of the cases with clinically relevant variants, compared to zero cases in stage I-IIIa (p = 0.004). Furthermore, one variant in EGFR, two in KRAS, and one in BRAF were detected in plasma but not in tumor samples.Conclusion: This study concludes that in the vast majority of advanced NSCLC patients a reliable variant analysis can be performed using liquid biopsy from plasma. Furthermore, we found that the number of variants in plasma is associated with prognosis, possibly indicating a strategy for closer follow up on this crucial patient group.
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