| 1. |
- Bonagas, Nadilly, et al.
(author)
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Pharmacological targeting of MTHFD2 suppresses acute myeloid leukemia by inducing thymidine depletion and replication stress
- 2022
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In: NATURE CANCER. - : Springer Science and Business Media LLC. - 2662-1347. ; 3:2, s. 156-
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Journal article (peer-reviewed)abstract
- The folate metabolism enzyme MTHFD2 (methylenetetrahydrofolate dehydrogenase/cyclohydrolase) is consistently overexpressed in cancer but its roles are not fully characterized, and current candidate inhibitors have limited potency for clinical development. In the present study, we demonstrate a role for MTHFD2 in DNA replication and genomic stability in cancer cells, and perform a drug screen to identify potent and selective nanomolar MTHFD2 inhibitors; protein cocrystal structures demonstrated binding to the active site of MTHFD2 and target engagement. MTHFD2 inhibitors reduced replication fork speed and induced replication stress followed by S-phase arrest and apoptosis of acute myeloid leukemia cells in vitro and in vivo, with a therapeutic window spanning four orders of magnitude compared with nontumorigenic cells. Mechanistically, MTHFD2 inhibitors prevented thymidine production leading to misincorporation of uracil into DNA and replication stress. Overall, these results demonstrate a functional link between MTHFD2-dependent cancer metabolism and replication stress that can be exploited therapeutically with this new class of inhibitors. Helleday and colleagues describe a nanomolar MTHFD2 inhibitor that causes replication stress and DNA damage accumulation in cancer cells via thymidine depletion, demonstrating a potential therapeutic strategy in AML tumors in vivo.
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| 2. |
- Arvidsson, Anna, 1973, et al.
(author)
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Early interactions between leukocytes and three different potentially bioactive titanium surface modifications
- 2011
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In: Journal of Biomedical Materials Research. Part B - Applied biomaterials. - : Wiley. - 1552-4973 .- 1552-4981. ; 97:2, s. 364-72
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Journal article (peer-reviewed)abstract
- The aim of the present study was to compare the early interactions between leukocytes and three different surface modifications, suggested as bioactive. Blasted titanium discs were modified by alkali and heat treatment, sodium fluoride treatment, or hydroxyapatite coating. A number of these discs were also immersed in simulated body fluid (SBF) for a week, a treatment which yielded high levels of calcium and phosphate on each surface type. The specimens were exposed for human venous blood for 32 minutes and the respiratory burst response was measured in terms of reactive oxygen species with a luminometer, and coverage of viable cells with a fluorescence microscope after staining steps. The topography, morphology, and chemistry of the surfaces were evaluated with optical interferometry and scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDX). A high respiratory burst response was found for HA coated titanium in comparison with the other surface groups (p < 0.0005). The SBF immersion resulted in an increased respiratory burst response (p < 0.0005) and removed statistically significant differences between the surface groups. Thus, the results in the present study indicate that different titanium surface modifications influence the early inflammatory response differently, and that calcium phosphate compounds increase the inflammatory response.
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| 3. |
- Arvidsson, Per Martin, et al.
(author)
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Kinetic energy of left ventricular blood flow across heart failure phenotypes and in subclinical diastolic dysfunction
- 2022
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In: Journal of Applied Physiology. - : American Physiological Society. - 1522-1601 .- 8750-7587. ; 133:3, s. 697-709
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Kinetic energy (KE) of intracardiac blood flow reflects myocardial work spent on accelerating blood and provides a mechanistic window into diastolic filling dynamics. Diastolic dysfunction may represent an early stage in the development of heart failure (HF). Here we evaluated the hemodynamic effects of impaired diastolic function in subjects with and without HF, testing the hypothesis that left ventricular KE differs between controls, subjects with subclinical diastolic dysfunction (SDD), and HF patients.METHODS: We studied 77 subjects (16 controls, 20 subjects with SDD, 16 HFpEF, 9 HFmrEF, and 16 HFrEF patients, age- and sex-matched at the group level). Cardiac magnetic resonance at 1.5T included intracardiac 4D flow and cine imaging. Left ventricular KE was calculated as 0.5*m*v 2. RESULTS: Systolic KE was similar between groups (p>0.4), also after indexing to stroke volume (p=0.25), and was primarily driven by ventricular emptying rate (p<0.0001, R 2=0.52). Diastolic KE was higher in heart failure patients than controls (p<0.05) but similar between SDD and HFpEF (p>0.18), correlating with inflow conditions (E-wave velocity, p<0.0001, R 2=0.24) and end-diastolic volume (p=0.0003, R 2=0.17) but not with average e' (p=0.07). CONCLUSIONS: Diastolic KE differs between controls and heart failure, suggesting more work is spent filling the failing ventricle, while systolic KE does not differentiate between well-matched groups with normal ejection fraction even in the presence of relaxation abnormalities and heart failure. Mechanistically, KE reflects the acceleration imparted on the blood and is driven by variations in ventricular emptying and filling rates, volumes, and heart rate, regardless of underlying pathology.
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| 4. |
- Arvidsson, Per Martin, et al.
(author)
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Kinetic energy of left ventricular blood flow across heart failure phenotypes and in subclinical diastolic dysfunction.
- 2022
-
In: Journal of applied physiology (Bethesda, Md. : 1985). - : American Physiological Society. - 1522-1601.
-
Journal article (peer-reviewed)abstract
- Kinetic energy (KE) of intracardiac blood flow reflects myocardial work spent on accelerating blood and provides a mechanistic window into diastolic filling dynamics. Diastolic dysfunction may represent an early stage in the development of heart failure (HF). Here we evaluated the hemodynamic effects of impaired diastolic function in subjects with and without HF, testing the hypothesis that left ventricular KE differs between controls, subjects with subclinical diastolic dysfunction (SDD), and HF patients.We studied 77 subjects (16 controls, 20 subjects with SDD, 16 HFpEF, 9 HFmrEF, and 16 HFrEF patients, age- and sex-matched at the group level). Cardiac magnetic resonance at 1.5T included intracardiac 4D flow and cine imaging. Left ventricular KE was calculated as 0.5*m*v2.Systolic KE was similar between groups (p>0.4), also after indexing to stroke volume (p=0.25), and was primarily driven by ventricular emptying rate (p<0.0001, R2=0.52). Diastolic KE was higher in heart failure patients than controls (p<0.05) but similar between SDD and HFpEF (p>0.18), correlating with inflow conditions (E-wave velocity, p<0.0001, R2=0.24) and end-diastolic volume (p=0.0003, R2=0.17) but not with average e' (p=0.07).Diastolic KE differs between controls and heart failure, suggesting more work is spent filling the failing ventricle, while systolic KE does not differentiate between well-matched groups with normal ejection fraction even in the presence of relaxation abnormalities and heart failure. Mechanistically, KE reflects the acceleration imparted on the blood and is driven by variations in ventricular emptying and filling rates, volumes, and heart rate, regardless of underlying pathology.
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| 5. |
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| 6. |
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| 7. |
- Almobarak, Bilal, et al.
(author)
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Exposure to nonanoic acid alters small intestinal neuroendocrine tumor phenotype
- 2023
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In: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 23:1
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Journal article (peer-reviewed)abstract
- BackgroundSmall intestinal neuroendocrine tumors (SI-NET) are highly differentiated and genetically stable malignant tumors, yet they often present with advanced metastatic spread at the time of diagnosis. In contrast to many other types of malignant tumors, primary SI-NET are often asymptomatic and typically smaller in size compared to adjacent lymph node metastases. This study explores the hypothesis that stimulating the chemosensing olfactory receptor 51E1 (OR51E1) decreases SI-NET proliferation suggesting a mechanism that explains a difference in proliferative rate based on tumor location.MethodsClinical data was used to address difference in tumor size depending on location. A SI-NET tissue microarray was used to evaluate expression of OR51E1 and olfactory marker protein (OMP). Primary cultured tumor cells from 5 patients were utilized to determine the effect of OR51E1 agonist nonanoic acid on metabolic activity. The SI-NET cell line GOT1 was used to determine effects of nonanoic acid on the transcriptome as well as long-term effects of nonanoic acid exposure with regards to cell proliferation, serotonin secretion, alterations of the cell-cycle and morphology.ResultsTumor size differed significantly based on location. OR51E1 and OMP were generally expressed in SI-NET. Primary SI-NET cells responded to nonanoic acid with a dose dependent altered metabolic activity and this was replicated in the GOT1 cell line but not in the MCF10A control cell line. Nonanoic acid treatment in GOT1 cells upregulated transcripts related to neuroendocrine differentiation and hormone secretion. Long-term nonanoic acid treatment of GOT1 cells decreased proliferation, induced senescence, and altered cell morphology.ConclusionOur results raise the possibility that exposure of intraluminal metabolites could represent a mechanism determining aspects of the SI-NET tumor phenotype. However, we could not causally link the observed effects of nonanoic acid exposure to the OR51E1 receptor.
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| 8. |
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Aquatic Conservation with Focus on Margaritifera margaritifera : Proceedings of the International Conference in Sundsvall, Sweden, 12-14 August, 2009
- 2012
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Editorial proceedings (other academic/artistic)abstract
- The freshwater pearl mussel Margaritifera margaritifera (L.) has attracted a large human interest, since the mussel is fascinating from biological, cultural andenvironmental perspectives. The mussel has a complicated life cycle dependingon host fish, and has great demands on its habitat. Furthermore, the mussel is anenvironmental indicator, and is used as an umbrella and flagship species. Pearl fishing has been described in Sweden as early as in the 16th century and by Carl Linnaeus in the 18th century.Many freshwater pearl mussel populations have insufficient recruitment and therefore decrease in numbers, and many populations are even extinct. Therefore, conservation work on the freshwater pearl mussel is going on all over Europe. Actions to preserve the freshwater pearl mussel will also favour other aquatic species – freshwater pearl mussel conservation is aquatic biodiversity conservation! WWF (World Wide Fund for Nature) Sweden implemented the project “The Freshwater Pearl Mussel and its habitats in Sweden” during 2004-2009 (LIFE04NAT/SE/000231). The overall objective was to improve the habitats of juvenile freshwater pearl mussels and the host fish brown trout Salmo trutta in21 streams. The actions were improvements of the biotopes, re-introduction of mussels, information to the stakeholders, and development of planning methods. An international conference “Aquatic Conservation with Focus on the Freshwater Pearl Mussel Margaritifera margaritifera” was held in Sundsvall 12–14 August, 2009. In these proceedings, presentations from the conference are published.
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| 9. |
- Arup, Ulf, et al.
(author)
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Lavar Lichenes
- 2015
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In: Rödlistade arter i Sverige 2015. - 9789187853104 ; , s. 72-79
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Book chapter (other academic/artistic)
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| 10. |
- Arvidsson, Anna, 1973, et al.
(author)
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Formation of calcium phosphates on titanium implants with four different bioactive surface preparations. An in vitro study
- 2007
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In: Journal of Materials Science-Materials in Medicine. - : Springer Science and Business Media LLC. - 0957-4530 .- 1573-4838. ; 18:10, s. 1945-1954
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Journal article (peer-reviewed)abstract
- The aim of the present study was to compare the nucleating and growing behaviour on four types of bioactive surfaces by using the simulated body fluid (SBF) model. Titanium discs were blasted and then prepared by alkali and heat treatment, anodic oxidation, fluoridation, or hydroxyapatite coating. The discs were immersed in SBF for 1, 2, 4 and 6 weeks. Calcium phosphates were found on all specimens, as analysed with scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDX). After 1 and 2 weeks of SBF immersion more titanium was accessible with SEM/EDX on the blasted surfaces than the four bioactive surface types, indicating a difference in coverage by calcium phosphates. The Ca/P mean ratio of the surfaces was approximately 1.5 after 1 week, in contrast to the fluoridated specimens which displayed a Ca/P mean ratio of approximately 2. Powder X-ray diffraction (P-XRD) analyses showed the presence of hydroxyapatite on all types of surfaces after 4 and 6 weeks of immersion. The samples immersed for 6 weeks showed a higher degree of crystallinity than the samples immersed for 4 weeks. In conclusion, differences appeared at the early SBF immersion times of 1 and 2 weeks between controls and bioactive surface types, as well as between different bioactive surface types.
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| 11. |
- Arvidsson, Björn, 1952-, et al.
(author)
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Förändringar och kontinuitet i vardagslivets Värmland
- 2008
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Reports (other academic/artistic)abstract
- Den här studien ingår i Karlstads universitets och fakultetens för samhälls- och livsvetenskaper satsning på mångvetenskaplig forskning om "uthålliga livsmiljöer och komplexa nätverk". Målet med fakultetens satsning är att stimulera forskning och samverkan mellan offentliga och privata aktörer så att Karlstads universitet effektivt kan bidra till och bli en motor i det långsiktigt hållbara utvecklingsarbetet i regionen. Studien tar sin utgångspunkt i intervjuer med några värmländska familjer om hur vardagen gestaltar sig idag, hur det såg ut historiskt och hur det kan tänkas se ut i framtiden. Intervjuerna kommenteras av forskare från olika ämnesområden. I mötet mellan forskare från olika ämnen och forskningstraditioner uppstår nya sätt att problematisera det komplicerade växelspelet mellan olika sektorer av vår tillvaro. Problemen kan omformuleras, nya möten och kontakter vänder invanda tankegångar mot nya och innovativa riktningar och beredskapen att möta framtida utmaningar såväl för forskare som för regionala aktörer stärks och uppgraderas. Förhoppningen är att studien ska fungera som en plattform för den viktiga diskussionen kring uthållig regional utveckling för kvinnor, män, barn och gamla och stimulera innovationer och forskning som garanterar en framtid där utveckling och tillväxt balanseras mot uthållig miljö för människor och natur.
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| 12. |
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| 13. |
- Arvidsson, Björn L, 1952-, et al.
(author)
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Recruitment of the threatened mussel Margaritifera margaritifera in relation to mussel population size, mussel density and host density
- 2012
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In: Aquatic conservation. - Malden, MA : John Wiley & Sons. - 1052-7613 .- 1099-0755. ; 22, s. 526-532
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Journal article (peer-reviewed)abstract
- Anthropogenic, abiotic factors are considered main causes of recruitment failure of unionid mussels, including the freshwater pearl mussel (Margaritifera margaritifera). In this large-scale investigation, we instead examined the relationship between biotic factors and mussel recruitment.Juvenile mussel density was positively related to both mussel population size and density of which the last appeared to be a more accurate measure of recruitment.Host fish density of young-of-the-year and older brown trout (Salmo trutta) were positively related to recruitment. Moreover, the mean density of both age classes of fish, when grouped into density classes was positively related to juvenile mussel density, an effect that decreased at trout densities above 10 trout 100 m-2.There was a higher relative importance of mussel population size and density than trout density to recruitment.To increase recruitment of juvenile mussels, managers may apply measures that increase mussel density, and trout density up to about 10 trout 100 m-2 in connection to mussel beds. Mussel beds may also be managed and one possible measure within small and sparse mussel populations may be to concentrate the remaining mussels to areas where trout density is high. Likewise, young-of-the-year trout may also be moved to areas of high mussel density, as young trout individuals are relatively resident during their first year. This may increase mussel larval infection rates and mussel recruitment.
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| 14. |
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| 15. |
- Arvidsson, Emma, et al.
(author)
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Pattern and orientation of diffusers in rooms with an absorbent ceiling
- 2019
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In: Proceedings of the 23rd International Congress on Acoustics : Integrating 4th EAA Euroregio 2019 - Integrating 4th EAA Euroregio 2019. - 2226-7808 .- 2415-1599. - 9783939296157 ; 2019-September, s. 2281-2288
-
Conference paper (peer-reviewed)abstract
- Lately have the demands on good room acoustics in public ordinary rooms increased. Traditionally has only reverberation time been considered in this type of rooms but complementary parameters as sound strength and speech clarity are more commonly used today. This trend naturally implies higher demands on the acoustic treatment. Typical for public ordinary rooms is to use an absorbent ceiling. One way to further improve the acoustic properties is to complement the ceiling treatment with diffusers. To investigate the effect of combining these two types of acoustic treatments have measurements been carried out combing different setups of diffusers in a reverberant room with an absorbent ceiling. The impact on reverberation time, speech clarity and sound strength has been studied. In this paper we present how diffusers can be used in order to improve the acoustic properties in a public ordinary room with an absorbent ceiling and how the pattern and orientation of diffusers can be used to adjust different acoustic parameters.
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| 16. |
- Arvidsson, Ida, et al.
(author)
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Shiga toxin-induced complement-mediated hemolysis and release of complement-coated red blood cell-derived microvesicles in hemolytic uremic syndrome.
- 2015
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In: Journal of Immunology. - : The American Association of Immunologists. - 1550-6606 .- 0022-1767. ; 194:5, s. 2309-2318
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Journal article (peer-reviewed)abstract
- Shiga toxin (Stx)-producing Escherichia coli (STEC) cause hemolytic uremic syndrome (HUS). This study investigated whether Stx2 induces hemolysis and whether complement is involved in the hemolytic process. RBCs and/or RBC-derived microvesicles from patients with STEC-HUS (n = 25) were investigated for the presence of C3 and C9 by flow cytometry. Patients exhibited increased C3 deposition on RBCs compared with controls (p < 0.001), as well as high levels of C3- and C9-bearing RBC-derived microvesicles during the acute phase, which decreased after recovery. Stx2 bound to P1 (k) and P2 (k) phenotype RBCs, expressing high levels of the P(k) Ag (globotriaosylceramide), the known Stx receptor. Stx2 induced the release of hemoglobin and lactate dehydrogenase in whole blood, indicating hemolysis. Stx2-induced hemolysis was not demonstrated in the absence of plasma and was inhibited by heat inactivation, as well as by the terminal complement pathway Ab eculizumab, the purinergic P2 receptor antagonist suramin, and EDTA. In the presence of whole blood or plasma/serum, Stx2 induced the release of RBC-derived microvesicles coated with C5b-9, a process that was inhibited by EDTA, in the absence of factor B, and by purinergic P2 receptor antagonists. Thus, complement-coated RBC-derived microvesicles are elevated in HUS patients and induced in vitro by incubation of RBCs with Stx2, which also induced hemolysis. The role of complement in Stx2-mediated hemolysis was demonstrated by its occurrence only in the presence of plasma and its abrogation by heat inactivation, EDTA, and eculizumab. Complement activation on RBCs could play a role in the hemolytic process occurring during STEC-HUS.
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| 17. |
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| 18. |
- Arvidsson, Martin, 1973, et al.
(author)
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A Product Robustness Process in a Medium-Sized Company
- 2012
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In: IIE Asia Conference 2012, 28-30 June, Singapore.
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Conference paper (peer-reviewed)abstract
- Robust Design Methodology (RDM) has been established as an approach to design products or processes that are reliable and have stable performance despite exposure to variation in uncontrollable factors. Reliable and robust products with stable performance reduce scrap, waste and re-work and thus contribute to increased sustainability. Research on RDM has traditionally focused on the application of various tools to support RDM. Less has been written on how RDM can be applied throughout a product development process. This paper presents a study of a medium-sized manufacturing company developing a Product Robustness Process (PRP) as a sub-process in their product development process; a process focusing on practices but also in some cases include indications of suitable tools. The resulting process shows how various practices of RDM can be made a part of an established product development process, from concept design to verification of reliability and robustness. It also shows the necessity to focus on practices, not merely tools or techniques, to make full use of RDM in all phases of product development.
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| 19. |
- Arvidsson, Martin, 1973, et al.
(author)
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A Review of Robust Design
- 2005
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In: 8th QMOD International Conference, Palermo.
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Conference paper (peer-reviewed)
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| 20. |
- Arvidsson, Martin, 1973, et al.
(author)
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A Robust Design Methodology Process
- 2014
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In: International Symposiu of Robust Design, Copenhagen, August 2014.
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Conference paper (peer-reviewed)abstract
- Robust Design Methodology (RDM) has been established as an approach to design products that are reliable and have stable performance despite exposure to variation in uncontrollable factors. Research on RDM has traditionally focused on the application of various tools to support RDM. Less has been written on how RDM practices can be applied throughout a product development (PD) process. This paper presents a study of a medium-sized manufacturing company working with a Product Robustness Process (PRP). PRP is a sub-process in their PD, and focuses mainly on practices supporting RDM and the outcome in terms of increased robustness. An example of a practice is to systematically identify factors that will vary under operating conditions and affect product performance and reliability. By knowledge of such factors it is possible to take robustness into account in early PD phases. In some phases of the PRP, indications of suitable tools are given, however not as a compulsory prescription. The PRP shows how practices of RDM can be made a part of an established PD process. It also aims to focus on practices, rather than tools or techniques, to maximise RDM application. Case studies on RDM are often focusing on tools such as Design of Experiments; albeit important it is of value to consider daily RDM practices without necessarily involving a prescribed tool. This paper aims at contributing to the latter by means of a case study at a company working with a PRP for about two years. The purpose of the paper is to describe and evaluate a process for RDM practices throughout PD. The most important outcome of the PRP is that the development teams have reliased a systematic way to address quality and reliability on the agenda throughout PD.
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| 21. |
- Arvidsson, Martin, 1990-
(author)
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Beyond Generative Sufficiency : On Interactions, Heterogeneity & Middle-Range Dynamics
- 2022
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Doctoral thesis (other academic/artistic)abstract
- Explaining how properties at the level of individuals translate into properties at the level of collectives is a core objective of sociology. Because the social world is characterized by complex webs of social interdependencies, establishing how micro and macro are related to one another requires a detailed understanding of how individuals are influenced by their social environments and the consequences that such influences have for the dynamics of the social process. However, until very recently, it has been difficult to conduct detailed empirical investigations of micro-macro linkages due to the lack of large-scale data containing information on how individuals interact with one another. In the absence of such data, substantive research has tended to (a) focus its attention elsewhere: studying how social factors influence individual outcomes, rather than how actors in interaction with one another bring about collective outcomes, or (b) propose models of micro-macro linkages that—for reasons of parsimony and tractability—often assume artificially high levels of homogeneity. Against this background, this thesis sets out to investigate, first, how the data and tools that have emerged from the digital and computational revolution can help sociologists construct empirically well-founded mappings from the micro to the macro level, and second, how the conclusions about the role of social interdependencies and networks change when the analysis is informed by real-world heterogeneities.In the introductory chapter, a conceptual and analytical framework for studying micro-macro processes is proposed that integrates the theoretical principles of analytical sociology with the data and methods of computational social science. This framework constitutes the foundation of the thesis. It is used in Essays I-III, and it is methodologically built upon in Essay IV.In Essay I, the role of social networks in labor-market segregation processes is examined. Scholarship on labor-market segregation commonly assume that social networks have a segregating effect because of homophilous selection tendencies in network-based recruitment. Using large-scale register data and focusing attention on individuals’ heterogenous opportunities to form same-category ties in different workplaces, Essay I finds that opportunity structures often dominate homophilic preferences. In particular, a mechanism is identified which shows—in contradiction with the main tenet of previous research—that networks often reduce rather than increase segregation by triggering mobility events that counteract the impact of segregating mobility events.Essay II examines the conditions under which social influence can decouple adoption behaviour from individual preferences and thereby bring about unexpected collective outcomes. Prior research has shown that such decoupling can occur, but conflicting evidence and implicit assumptions of strong homogeneity mean that we still know little about the conditions under which this is likely to occur in the real world. Addressing these limitations, this study uses fine-grained, real-world behavioural data from Spotify to estimate heterogeneous social influence effects conditional on properties of individuals’ social environments, and then examine their macro-implications in empirically calibrated simulations. It is found that partial overlap in preferences and strong social ties between the senders and receivers of social influence is needed for social influence to produce decoupling.Essay III centers on the phenomenon of urban scaling and examines the relationship between within-city and between-city inequality. Previous urban scaling research has documented how cities’ total outputs increase more than proportionally with city size and has proposed theoretical models which demonstrate impressive predictive accuracy at aggregate levels. However, this research has overlooked the stark inequalities that exist within cities. Using microdata from multiple countries, it is found that between 36–80% of the previously reported scaling effects can be explained by differences in the distributional tails of cities. Providing explanatory depth to these findings, a cumulative advantage mechanism is identified which elucidates one important channel through which differences in the size of cities’ tails emerge.In Essay IV, a method is proposed for inferring theoretically meaningful dimensions from complex high-dimensional data such as text. The results show that the method captures latent semantic concepts better than or on-par with the current state of the art. For the study of social interactions, the method constitutes a new and potentially important tool for inferring theoretically meaningful dimensions about individuals and their social environments, and in so doing, improves our ability to adjust for specific types of homophily and enables richer and more precise measures of heterogeneity in social interaction processes.
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| 22. |
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| 23. |
- Arvidsson, Moa, et al.
(author)
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Drone Navigation and License Place Detection for Vehicle Location in Indoor Spaces
- 2024
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In: Lect. Notes Comput. Sci.. - Heidelberg : Springer Science and Business Media Deutschland GmbH. - 9783031495519 - 9783031495526 ; , s. 362-374
-
Conference paper (peer-reviewed)abstract
- Millions of vehicles are transported every year, tightly parked in vessels or boats. To reduce the risks of associated safety issues like fires, knowing the location of vehicles is essential, since different vehicles may need different mitigation measures, e.g. electric cars. This work is aimed at creating a solution based on a nano-drone that navigates across rows of parked vehicles and detects their license plates. We do so via a wall-following algorithm, and a CNN trained to detect license plates. All computations are done in real-time on the drone, which just sends position and detected images that allow the creation of a 2D map with the position of the plates. Our solution is capable of reading all plates across eight test cases (with several rows of plates, different drone speeds, or low light) by aggregation of measurements across several drone journeys.
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| 24. |
- Arvidsson, Martin, et al.
(author)
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Feeling fine – the effect of topography and friction on perceived roughness and slipperiness
- 2016
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Other publication (other academic/artistic)abstract
- To be able to design materials with specific haptic qualities, it is important to understand not only the contribution of physical attributes from the surfaces of the materials, but also the perceptions that are involved in the haptic interaction with the materials. A series of 16 wrinkled surfaces with two different materials (Young’s modulus of 1,600 and 20,000 psi, respectively) and 8 different wrinkle wavelengths (30‑120 µm, and two unwrinkled reference surfaces) were thus characterized in terms of surface roughness and finger friction coefficient. Sixteen participants scaled the perceived Roughness and Slipperiness of the surfaces using the method of free magnitude estimation. Five of the sixteen participants conducted friction measurements during their perceived slipperiness session, and an experimenter conducted friction measurements in a separate experiment with higher experimental control. The trends in friction properties were similar for the group of participants performing the friction measurements in an uncontrolled way and the experiments performed under well-defined conditions, showing that the latter type of measurements represent the general friction properties well. The results point to slipperiness as the key perception dimension for textures below 100 µm and roughness above 100 µm. In the interval between 30 and 50 µm it is hard to discriminate between the wavelengths, these surfaces also exhibit the highest slipperiness and the lowest roughness. Furthermore, it is apparent that roughness and slipperiness perception of these types of structures are not independent; which is also supported by an increased friction between 80‑100 µm that corresponds well with both a change in slipperiness and in roughness. The increased friction in this specific wavelength region is related to an increased contact area between finger and material. Somewhat surprising was the fact that the material with the higher Young’s modulus was perceived as more slippery, especially for the smaller wavelengths, this is also the range where it was difficult to differentiate between the wavelengths. A concluding finding was that the flat (high friction) references surfaces were scaled as rough, supporting the theory that perceived roughness itself is a multidimensional construct with both surface roughness and friction components.
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| 25. |
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| 26. |
- Arvidsson, Martin, 1978-
(author)
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Getting a Feel for Tactile Space : Exploring Haptic Perception of Microtexture
- 2012
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Doctoral thesis (other academic/artistic)abstract
- The present thesis is based on three studies that research different aspects of fine texture perception. The goal is to better understand the mechanisms involved in haptic perception of textures below 200 µm, also known as microtextures. Study I was conducted to establish a friction measurement model and relating the friction measurements to perceived coarseness of fine textures. A set of printing papers was used as stimulus material. In Study II an expanded set, including the set of Study I, was used as stimuli in a multidimensional scaling (MDS) experiment of haptic fine texture perception. Through scaling of perceptual attributes and similarities, a three dimensional space was found to best describe the data and the dimensions were interpreted as rough-smooth, thick-thin and distinct-indistinct. In Study III a series of model surfaces were manufactured with a systematically varied sinusoidal pattern, spanning from 300 nm to 80 µm. As in Study II, a similarity experiment was conducted and a two dimensional space was chosen, the dimensions of which were explained well through friction and the wavelength. Together these three studies form a better picture of fine texture perception. The dimensionality found with paper stimuli was very similar to the corresponding spaces for marcrotextures of everyday materials, even though a different perceptual system is used for fine texture perception. Regardless if the information is coded through the spatial or the vibratory sense, the perception does not seem to differ in dimensionality. Further, the largest among the microtextures seem to have been perceived as carrying spatial information. On the systematically varied, rigid, textures, the MDS space did not come out in a similar fashion to those of everyday materials but instead similar to the physical properties that characterizes the change in the textures. It was further found that the participants in Study III successfully discriminated textures with an amplitude of 13 nm from the unwrinkled surfaces. From these studies the main conclusions are (a) haptically measured friction and surface roughness are important contributors to fine texture perception, (b) even at microscales, spatial information is retrieved haptically, probably through vibrations, and (c) persons can haptically discriminate textures at a nanoscale.
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| 27. |
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| 28. |
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| 29. |
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| 30. |
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| 31. |
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| 32. |
- Arvidsson, Martin, et al.
(author)
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Multidimensional psychophysics : Surface feel of printing paper as a function of physical properties
- 2009
-
In: Fechner Day 2009. - Galway, Irland : International Society for Psychophysics. ; , s. 215-220
-
Conference paper (other academic/artistic)abstract
- The aim of this experiment was to explore the perception of tactile surface-feel of 21 printing papers. A multidimensional scaling (MDS) experiment was conducted with 20 women. They scaled similarity among all possible pairs of the papers. Similarity measurements were mapped by INDSCAL and modeled with PREFMAP. Test-retest and concordance coefficients were high. It is not yet established what physical properties best determine tactile feel. It seems likely though that finger friction and surface roughness are strong contenders. Finger friction for the papers was measured as a ratio of friction force to normal force;(while stroking a human finger on the surface. Average surface roughness was measured with a profilometer. Physical properties were rotated into the 3D INDSCAL solution. This solution identified and mapped the tactile surface feel of the papers in an interpretable way with regard to i.e. friction, surface roughness and weight.
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| 33. |
- Arvidsson, Martin, 1973
(author)
-
Robust Design Experimentation and Dispersion Effects
- 2003
-
Doctoral thesis (other academic/artistic)abstract
- One of the most common methods in robust design methodology is design of experiments. This method makes it possible to identify settings of design factors that make products and production processes robust with respect to noise factors. In practice, this may be done by searching for interactions between design factors and noise factors that can be used to diminish the effect of noise factors on important performance characteristics. In the appended Papers D and E it is argued that a dispersion effect can be viewed as an interaction between a design factor, deliberately controlled in the experiment, and an uncontrolled factor. Provided that all potentially active design factors have been included in the experiment, it is reasonable to view the uncontrolled factors as noise factors. Papers D and E propose methods for identifying dispersion effects in unreplicated completely randomized two-level fractional factorials. Split-plot experiments are well suited in robust design experimentation as they allow for a precise estimation of effects related to interactions between design factors and noise factors. Split-plot experiments are also cheaper to conduct than completely randomized experiments. However, traditional analyses of split-plot experiments have not made use of all the information that can be extracted from the experiments. The work reported in this thesis sheds some light on alternative methods of analysis that use information more efficiently than in the traditional methods of analysis. Specifically, Papers A and B propose methods for the analysis of split-plot experiments that make it possible to find opportunities for improving the robustness of products and processes. The suggested methods offer more subtle knowledge of how factors influence location and dispersion. Paper C presents a decision tree that links different restrictions in randomization to their consequences on the experiment. This tree facilitates deliberate choices of restrictions - choices that have consequences that are favorable with respect to the cost and information content of the experiment. Finally, Paper F presents the results of a telephone survey on the use and knowledge of robust design methodology in Swedish manufacturing industry.
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| 34. |
- Arvidsson, Martin, et al.
(author)
-
The Trojan-horse mechanism : How networks reduce gender segregation
- 2021
-
In: Science Advances. - : American Association for the Advancement of Science. - 2375-2548. ; 7:16
-
Journal article (peer-reviewed)abstract
- The segregation of labor markets along ethnic and gender lines is socially highly consequential, and the social science literature has long viewed homophily and network-based job recruitments as some of its most crucial drivers. Here, we focus on a previously unidentified mechanism, the Trojan-horse mechanism, which, in contradiction to the main tenet of previous research, suggests that network-based recruitment reduce rather than increase segregation levels. We identify the conditions under which networks are desegregating, and using unique data on all individuals and all workplaces located in the Stockholm region during the years 2000-2017, we find strong empirical evidence for the Trojan-horse mechanism and its role in the gender segregation of labor markets.
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| 35. |
- Arvidsson, Martin, 1990-, et al.
(author)
-
Urban scaling laws arise from within-city inequalities
- 2023
-
In: Nature Human Behaviour. - : Nature Publishing Group. - 2397-3374. ; 7:3, s. 365-374
-
Journal article (peer-reviewed)abstract
- Theories of urban scaling have demonstrated remarkable predictive accuracy at aggregate levels. However, they have overlooked the stark inequalities that exist within cities. Human networking and productivity exhibit heavy-tailed distributions, with some individuals contributing disproportionately to city totals. Here we use micro-level data from Europe and the United States on interconnectivity, productivity and innovation in cities. We find that the tails of within-city distributions and their growth by city size account for 36–80% of previously reported scaling effects, and 56–87% of the variance in scaling between indicators of varying economic complexity. Providing explanatory depth to these findings, we identify a mechanism—city size-dependent cumulative advantage—that constitutes an important channel through which differences in the size of tails emerge. Our findings demonstrate that urban scaling is in large part a story about inequality in cities, implying that the causal processes underlying the heavier tails in larger cities must be considered in explanations of urban scaling. This result also shows that agglomeration effects benefit urban elites the most, with the majority of city dwellers partially excluded from the socio-economic benefits of growing cities.
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| 36. |
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| 37. |
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| 38. |
- Arvidsson, Per M, et al.
(author)
-
Hemodynamic force analysis is not ready for clinical trials on HFpEF
- 2022
-
In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 12
-
Journal article (peer-reviewed)abstract
- Hemodynamic force analysis has been proposed as a novel tool for early detection of subclinical systolic dysfunction in heart failure with preserved ejection fraction (HFpEF). Here we investigated the ability of hemodynamic forces to discriminate between healthy subjects and heart failure patients with varying degrees of systolic dysfunction. We studied 34 controls, 16 HFpEF patients, and 25 heart failure patients with mid-range (HFmrEF) or reduced ejection fraction (HFrEF) using cardiac magnetic resonance with acquisition of cine images and 4D flow at 1.5 T. The Navier-Stokes equation was used to compute global left ventricular hemodynamic forces over the entire cardiac cycle. Forces were analyzed for systole, diastole, and the entire heartbeat, with and without normalization to left ventricular volume. Volume-normalized hemodynamic forces demonstrated significant positive correlation with EF (r2 = 0.47, p < 0.0001) and were found significantly lower in heart failure with reduced ejection fraction compared to controls (p < 0.0001 for systole and diastole). No difference was seen between controls and HFpEF (p > 0.34). Non-normalized forces displayed no differences between controls and HFpEF (p > 0.24 for all analyses) and did not correlate with EF (p = 0.36). Left ventricular hemodynamic force analysis, whether indexed to LV volumes or not, is not ready for clinical trials on HFpEF assessment.
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| 39. |
- Arvidsson, Per Martin, et al.
(author)
-
Quantification of left and right atrial kinetic energy using four-dimensional intracardiac magnetic resonance imaging flow measurements.
- 2013
-
In: Journal of Applied Physiology. - : American Physiological Society. - 1522-1601 .- 8750-7587. ; 114:10, s. 1472-1481
-
Journal article (peer-reviewed)abstract
- Kinetic energy (KE) of atrial blood has been postulated as a possible contributor to ventricular filling. Therefore, we aimed to quantify the left and right atrial blood KE using cardiac magnetic resonance (CMR). Fifteen healthy volunteers underwent CMR at 3T, including a four-dimensional phase contrast flow sequence. Mean left atrial (LA) KE was lower than right atrial (RA) KE (1.1±0.1 mJ vs 1.7±0.1 mJ, P<0.01). Three KE peaks were seen in both atria; one in ventricular systole, one during early ventricular diastole, and one during atrial contraction. The systolic LA peak was significantly smaller than the RA peak (P<0.001), and the early diastolic LA peak was larger than the RA peak (P<0.05). Rotational flow contained 46 ± 7% of total KE, and conserved energy better than non-rotational flow did. The KE increase in early diastole was higher in the LA (P<0.001). Systolic KE correlated with the combination of atrial volume and systolic velocity of the atrioventricular plane displacement (R2=0.57 for LA and R2=0.64 for RA). Early diastolic KE of the LA correlated with LV mass (R2=0.28), however no such correlation was found in the right heart. This suggests that LA KE increases during early ventricular diastole due to LV elastic recoil, indicating that LV filling is dependent on diastolic suction. RV relaxation does not seem to contribute to atrial KE. Instead, atrial KE generated during ventricular systole may be conserved in a hydraulic "flywheel" and transferred to the RV through helical flow, which may contribute to RV filling.
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| 40. |
- Arvidsson, Rickard, 1984, et al.
(author)
-
Challenges in Exposure Modeling of Nanoparticles in Aquatic Environments
- 2011
-
In: Human and Ecological Risk Assessment. - : Informa UK Limited. - 1080-7039 .- 1549-7860. ; 17:1, s. 245-262
-
Journal article (peer-reviewed)abstract
- Managing the potential environmental risks of nanoparticles requires methods to link nanoparticle properties with macro-scale risks. This study outlines challenges in exposure modeling of nanoparticles in aquatic environments, such as the role of natural organic matter, natural colloids, fractal dimensions of agglomerates, coatings and doping of particles, and uncertainties regarding nanoparticle emissions to aquatic environments. The pros and cons of the exposure indicators mass concentration, particle number concentration, and surface area are discussed. By applying colloid chemistry kinetic equations describing particle agglomeration and sedimentation for the case of titanium dioxide nanoparticles, a limited exposure assessment including some of the factors mentioned is conducted with particle number concentration as the exposure indicator. The results of the modeling indicate that sedimentation, shear flows, and settling are of less importance with regard to particle number based predicted environmental concentrations. The inflow of nanoparticles to the water compartment had a significant impact in the model, and the collision efficiency (which is affected by natural organic matter) was shown to greatly affect model output. Implications for exposure modeling, regulation and science are discussed. A broad spectrum of scientific disciplines must be engaged in the development of exposure models where nano-level properties are linked to macro-scale risk.
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| 41. |
- Arvidsson, Rickard, 1984, et al.
(author)
-
Exposure assessments of nanoparticles in aquatic environments – considerations, review and recommendations
- 2013
-
Reports (other academic/artistic)abstract
- Synthetic nanoparticles are new forms of chemical substances. They can be found in several different forms, such as free particles, surface bound and dissolved in liquid. Nanoparticles can also exist as free, individual particles or agglomerate consisting of multiple particles. This report discusses the assessment of possible risks of nanoparticles. Chemical risk is usually considered to consist of two elements: (1) Exposure to the substance, and (2) the substance's toxicity. So far, the risk-related research on nanoparticles has had a strong focus on the particles ' toxic effects. In this report, we would instead focus on how exposure to nanoparticles can be calculated and assessed, with focus on nanoparticles in water. In the report, we provide an initial background and definitions of nanomaterials and nanoparticles, and describe briefly a standard method of risk assessment of chemicals in the environment. Then we go through important considerations that should be made in the exposure assessment of nanoparticles. First we discuss three considerations related to the emissions of nanoparticles, namely the lack of data for annual production of nanoparticles, the importance of applying a substance flow perspective, and lack of data for so-called emission factors for nanoparticles of various products and materials. Furthermore, we discuss considerations for modeling of nanoparticles behavior in water, mainly by listing a number of key processes with large influence. These are agglomeration, sedimentation, and dissolution. Related to that, we discuss how natural organic materials, coatings and aging of particles can affect these processes. We note here three particle properties that are important in order to describe nanoparticles dispersion in water, in a similar way that the octanol-water partition coefficient and half-life is important to describe the fate of organic chemicals in the environment. For nanoparticles these are the particle size (a) and the density (ρ). We also identify a number of more complex parameters affecting particle behavior in the environment, but not only because of the different particle characteristics, but also depending on characteristics related to the environment. These are the collision efficiency (α), point of zero charge (pHpzc), Hamaker constant (A) and a so-called form factor (β) that affect the sedimentation. In addition to the general difficulty to measure or calculate these parameters they also co-vary. Furthermore, we make a review of 11 currently available exposure models for nanoparticles in aquatic environment. We note that the studies differ regarding modeling method, which sources of emissions that are included, the nanoparticles taken into account, estimated concentrations in the environment, and whether the results are presented as mass or particle concentration. Only two studies trying to model the nanoparticle exposure based on particle properties in a manner similar to standard methods for chemical risk assessment. The other modeling studies are instead based on data on flows of specific nanomaterials, and not on generic algorithms. Next, we describe a number of challenges that occur when measuring nanoparticles in the environment. Finally, we provide the following recommendations to ensure good exposure assessment of nanoparticles in the future: 1. Information of flows and stocks of nanoparticles in society need to be collected. 2. Emission factors would need to be developed for each product that makes use of nanoparticles. 3. Emissions should be reported both as mass and particle number until it becomes clearer which one is most relevant. 4. More research is needed in order to determine which particle properties need to be known in order to calculate the concentration of nanoparticles in the environment. 5. At least the particle size and particle size distribution, as well as the specific particle density should be reported. 6. More research is required to improve the experimental measurements of nanoparticles to be able to validate exposure models.
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| 42. |
- Arvidsson, Rickard, 1984, et al.
(author)
-
MODELLING ENVIRONMENTAL FATE OF TiO2 NANOPARTICLES IN WATER – IMPLICATIONS FOR EMPIRICAL VALIDATION STUDIES
- 2009
-
In: 4th International Conference on the Environmental Effects of Nanoparticles and Nanomaterials, 6-9 September, Vienna, Austria.
-
Conference paper (other academic/artistic)abstract
- The potential environmental effects of nanoparticles (NPs) require interdisciplinary research to assess the risks. One part of a risk assessment concerns exposure, which builds on knowledge of the environmental fate. In this particular case the fate of TiO2 NPs in the water compartment was modelled by applying a second order kinetic rate equation and the DLVO theory. Assumptions were made regarding water parameters such as pH, salt concentration and temperature, as well as regarding particle properties such as Hamaker constant, primary particle size and point of zero charge. The effect of sedimentation was taken into account, but as one would expect the influence of sedimentation on such small particles is very small. The model was implemented in MATLAB®. Results indicate the importance of agglomeration as an important fate mechanism, and that pH andpoint of zero charge are important parameters with regards to agglomeration. Other parameters such as the Hamaker constant, salt concentration and temperature were shown not to have a significant effect, which is in goodcorrelation with empirical studies. Also, we would like to see our model validated by empirical studies. Important implications then are to include a continuous inflowof NPs in the experimental setup and to work at environmentally relevant water properties. For example is the effect of natural organic matter (NOM) on theagglomeration not modelled, despite that its significance has been pointed out in many studies. This is due to a weak link between mathematical expressions andempirical data for this particular part of the model. It is of importance that this linkage is strengthened both by theoretical and empirical studies on NOM aimingat producing mathematical expressions, and empirical data, that can assist fate modelling of NPs.
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| 43. |
- Arvidsson, Victor, et al.
(author)
-
Evaluation of Defense Methods Against the One-Pixel Attack on Deep Neural Networks
- 2023
-
In: 35th Annual Workshop of the Swedish Artificial Intelligence Society SAIS 2023. - : Linköping University Electronic Press. - 9789180752749 ; , s. 49-57
-
Conference paper (peer-reviewed)abstract
- The one-pixel attack is an image attack method for creating adversarial instances with minimal perturbations, i.e., pixel modification. The attack method makes the adversarial instances difficult to detect as it only manipulates a single pixel in the image. In this paper, we study four different defense approaches against adversarial attacks, and more specifically the one-pixel attack, over three different models. The defense methods used are: data augmentation, spatial smoothing, and Gaussian data augmentation used during both training and testing. The empirical experiments involve the following three models: all convolutional network (CNN), network in network (NiN), and the convolutional neural network VGG16. Experiments were executed and the results show that Gaussian data augmentation performs quite poorly when applied during the prediction phase. When used during the training phase, we see a reduction in the number of instances that could be perturbed by the NiN model. However, the CNN model shows an overall significantly worse performance compared to no defense technique. Spatial smoothing shows an ability to reduce the effectiveness of the one-pixel attack, and it is on average able to defend against half of the adversarial examples. Data augmentation also shows promising results, reducing the number of successfully perturbed images for both the CNN and NiN models. However, data augmentation leads to slightly worse overall model performance for the NiN and VGG16 models. Interestingly, it significantly improves the performance for the CNN model. We conclude that the most suitable defense is dependent on the model used. For the CNN model, our results indicate that a combination of data augmentation and spatial smoothing is a suitable defense setup. For the NiN and VGG16 models, a combination of Gaussian data augmentation together with spatial smoothing is more promising. Finally, the experiments indicate that applying Gaussian noise during the prediction phase is not a workable defense against the one-pixel attack. ©2023, Copyright held by the authors
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| 44. |
- Assarlind, Marcus, 1983, et al.
(author)
-
A Process Analysis of an Implementation of Lean Six Sigma in a Manufacturing Medium-Sized Enterprise
- 2013
-
In: 20th EurOMA Conference, 9-11 June, Dublin.
-
Conference paper (peer-reviewed)abstract
- In the present paper we study the gradual adoption of Lean Six Sigma in a medium-sized Swedish manufacturing company. We identify converters moving the process forward or backward and inhibitors that cause the process to linger. We find that the activities that initially were moving the process forward were not enough to move the process beyond its current point. However, the increased knowledge of Lean Six Sigma in the organization now prevents the process from moving backwards. The paper contributes to the understanding of combining Lean and Six Sigma, improvement work in SMEs, and ex-post analyses of gradual adoptions of improvement work.
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| 45. |
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| 46. |
- Börjesson, Mats, 1965, et al.
(author)
-
Return to play after infectious disease
- 2018
-
In: Return to Play in Football. - Berlin, Heidelberg : Springer Verlag. - 9783662557129 ; , s. 755-70
-
Book chapter (other academic/artistic)
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| 47. |
- Carlsson, Göran, 1951, et al.
(author)
-
Verbal and non-verbal function of children with right- versus left-hemiplegic cerebral palsy of pre- and perinatal origin.
- 1994
-
In: Developmental medicine and child neurology. - 0012-1622. ; 36:6, s. 503-12
-
Journal article (peer-reviewed)abstract
- Eighteen children with right- and 13 with left-sided congenital hemiplegia were compared with 19 normal age-matched controls for verbal and non-verbal function. CT scans were obtained from 27 of the 31 hemiplegic children. The two hemiplegic groups were impaired in non-verbal function compared with controls. The right-hemiplegic group was more impaired in verbal function than the left-hemiplegic group and controls; however, impairments were restricted to the girls in the right-hemiplegic group. The results are discussed in terms of cerebral plasticity and functional reorganisation of cognitive functions after an early unilateral injury. It is argued that girls with left-hemisphere lesions may be more limited in cerebral plasticity than boys.
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| 48. |
- Chavez, Zuhara, et al.
(author)
-
From Surviving to Thriving : Industry 5.0 at SMEs Enhancing Production Flexibility
- 2023
-
In: Advances in Production Management Systems. - : Springer Nature. ; 689 AICT, s. 789-802
-
Conference paper (peer-reviewed)abstract
- This study explores how human-centered digitalization can contribute to the flexibility and adaptability of small and medium-sized enterprise (SME) production processes, resulting in more resilient systems. This study explains the relationship between digital technologies and production system features through progressively more human-centric stages of a digitalized manufacturing system. The authors present a case study of an SME that implemented a human-centric strategy, placing people's needs and interests at the center of its processes, leading to more flexible and inclusive production processes and consistent with the goals of Industry 5.0. The results suggest that a digitalized working method that considers human capabilities and needs can enable a more diverse workforce and the rapid setup of new and additional production processes, thus helping SMEs respond to supply chain disruptions. The findings have implications for managers and practitioners interested in driving or supporting the transition of SMEs to human-centric, resilient, and sustainable businesses.
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| 49. |
- Choong, Oi Kuan, 1985, et al.
(author)
-
SARS-CoV-2 replicates and displays oncolytic properties in clear cell and papillary renal cell carcinoma
- 2023
-
In: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 18:1
-
Journal article (peer-reviewed)abstract
- The SARS-CoV-2 virus is currently causing a global pandemic. Infection may result in a systemic disease called COVID-19, affecting primarily the respiratory tract. Often the gastrointestinal tract and kidneys also become involved. Angiotensin converting enzyme 2 (ACE2) serves as the receptor for SARS-CoV-2. The membrane proteins, Transmembrane serine protease 2 (TMPRSS2) and Neuropilin 1 (NRP1) are accessory proteins facilitating the virus entry. In this study we show that the human proximal kidney tubules, express these factors. We hypothesized that cancers derived from proximal tubules as clear cell (CCRCC) and papillary renal cell carcinoma (PRCC), retain the expression of the SARS-CoV-2 entry factors making these cancers susceptible to SARS-CoV-2 infection. We used bioinformatics, western blotting, and assessment of tissue micro arrays (TMA) including 263 cases of CCRCC, 139 cases of PRCC and 18 cases of chromophobe RCC to demonstrate that the majority of CCRCC and PRCC cases retained the RNA and protein expression of the entry factors for SARS-CoV-2. We furthermore show that SARS-CoV-2 virus propagated robustly in primary cultures of CCRCC and PRCC cells with a visible virus cytopathogenic effect correlating with viral RNA expression levels. We also noted that the delta-variant of SARS-CoV-2 causes cancer cells to form syncytia in-vitro. This phenomenon was also identified histologically in CCRCC tissue from a patient that had been hospitalized for COVID-19, twelve months prior to nephrectomy. Our data provide insights into SARS-CoV-2 infectivity in renal cell carcinoma and that the virus causes a distinct cytopathogenic effect.
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| 50. |
- Diamond, Miriam, et al.
(author)
-
Exploring the planetary boundary for chemical pollution
- 2015
-
In: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750. ; 78, s. 8-15
-
Research review (peer-reviewed)abstract
- Rockström et al. (2009a, 2009b) have warned that humanity must reduce anthropogenic impacts defined by nine planetary boundaries if “unacceptable global change” is to be avoided. Chemical pollution was identified as one of those boundaries for which continued impacts could erode the resilience of ecosystems and humanity. The central concept of the planetary boundary (or boundaries) for chemical pollution (PBCP or PBCPs) is that the Earth has a finite assimilative capacity for chemical pollution, which includes persistent, as well as readily degradable chemicals released at local to regional scales, which in aggregate threaten ecosystem and human viability. The PBCP allows humanity to explicitly address the increasingly global aspects of chemical pollution throughout a chemical's life cycle and the need for a global response of internationally coordinated control measures. We submit that sufficient evidence shows stresses on ecosystem and human health at local to global scales, suggesting that conditions are transgressing the safe operating space delimited by a PBCP. As such, current local to global pollution control measures are insufficient. However, while the PBCP is an important conceptual step forward, at this point single or multiple PBCPs are challenging to operationalize due to the extremely large number of commercial chemicals or mixtures of chemicals that cause myriad adverse effects to innumerable species and ecosystems, and the complex linkages between emissions, environmental concentrations, exposures and adverse effects. As well, the normative nature of a PBCP presents challenges of negotiating pollution limits amongst societal groups with differing viewpoints. Thus, a combination of approaches is recommended as follows: develop indicators of chemical pollution, for both control and response variables, that will aid in quantifying a PBCP(s) and gauging progress towards reducing chemical pollution; develop new technologies and technical and social approaches to mitigate global chemical pollution that emphasize a preventative approach; coordinate pollution control and sustainability efforts; and facilitate implementation of multiple (and potentially decentralized) control efforts involving scientists, civil society, government, non-governmental organizations and international bodies.
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