| 1. |
- Dahlin, Torleif, et al.
(författare)
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Novel electrode design for non-destructive resistivity measurement on material in geotechnical standard sample cylinders
- 2023
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Ingår i: Procs. Near Surface Geoscience 2023.
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Konferensbidrag (refereegranskat)abstract
- We present a novel design of an electrode arrangement for measurement of the resistivity of soil samples contained in a sample cylinder used in standard geotechnical site investigations in Sweden. The objective is to make it possible to measure the resistivity of the same samples that are to be used for mechanical tests, without disturbing the samples in order to get unbiased mechanical test data. A design with four piece-of- pie shaped electrodes integrated in the lids in each end of the sample has been tested and evaluated. Temperature sensors are embedded in the electrode lids to allow temperature compensation of the measured data.Alternative electrode designs were modelled numerically with the finite element method (FEM) prior to the prototype manufacturing. Measurement tests with water filled sample cylinders show that stacking and reciprocal errors can be kept below 1% provided that suitable measurement settings and sequences are used. The geometrical factors depends on the distance between the electrodes in each end of the cylinder, i.e. varies with the length of the sample, and must be determined experimentally or via FEM modelling.
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| 2. |
- Olsson, Per-Ivar, et al.
(författare)
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ASSERT - Kontroll av markstabilisering med resistivitetstomografi
- 2020
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Ingår i: ; , s. 1-10
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Konferensbidrag (refereegranskat)abstract
- Ground improvement with lime-cement pillars is becoming increasingly common in the Nordic countries for exploitation of areas with poor stability. However, there is a need for non-destructive methods for volumetric quality control of the ground improvement. The quality control can be divided into two steps where the first include quality control at the installation process with monitoring of production parameters such as rotation and penetration speed, air pressure and binder feed rate. The second step involves determining the spatial continuity and the mechanical properties of the treated subsurface after curing by for example a reversed pillar penetration test, complete exposure or core drilling. ASSERT (Assessment of Soil Stabilization using Electrical Resistivity Tomography) is an on-oing research project with focus on quality control in direct connection with mixing of the binders based on electrical resistivity tomography (ERT). The ERT-method has in several cases been shown to efficiently differentiate treated soil from untreated. Hence, is the method an interesting option for direct and rapid volumetric quality control of the stabilized soil so that zones which needs to be supplemented can be identified at production stage while personnel and equipment are at site. The ASSERT project involves test and verification of the method in different geological environments and scales, including full-scale tests for different types of stabilization techniques. Additionally, method development and adaptations to make the quality control applicable are also included in the project to enable a robust, rapid and sustainable use in routine operations.
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| 3. |
- Blicharska, Malgorzata, 1979-, et al.
(författare)
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Shades of grey challenge practical application of the Cultural Ecosystem Services concept
- 2017
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Ingår i: Ecosystem Services. - : Elsevier BV. - 2212-0416 .- 2212-0416. ; 23, s. 55-70
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Tidskriftsartikel (refereegranskat)abstract
- Despite rapid advances in development of the ecosystem services (ES) concept, challenges remain for its use in decision making. Cultural ES (CES) have proven particularly difficult to pin down and resultant “shades of grey” impede their consideration by decision-makers. This study undertakes a literature review of CES to highlight the shades of grey, briefly illustrates findings by reference to the Swedish mountain landscape, then addresses potential implications for practical decision making. The concept of CES is complex and difficult to operationalize. The root of confusion appears to be a lack of rigour in identifying CES, hindering identification of proper methods for determining: the ecosystem elements that underpin CES; the beneficiaries of CES and how they value benefits delivered; and how CES may vary in space and time. We conclude by proposing a framework of questions, which we relate to the ES cascade model, that is intended to help researchers and decision-makers to reflect when considering CES. Answers to the questions should enable decision-makers to prioritise policy development or implementation in relation to the differing needs of potentially competing beneficiaries and what needs to be done or not done to the ecosystem, where, when and by whom.
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| 4. |
- Dahlin, Torleif, et al.
(författare)
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ASSERT - Kontroll av markstabilisering med resistivitetstomografi (ERT)
- 2023
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Ingår i: ; , s. 219-228
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Konferensbidrag (refereegranskat)abstract
- Soil stabilisation is becoming increasingly common for the development of areas withpoor bearing capacity. However, there is a need for better and volume-wide controlmethods for quality assurance. The control methods can be divided into two steps,where the first takes place in immediate connection to the mixing of binders to checkwhether the entire intended volume has been successfully treated, or whether thereare zones that need completion. The second step focuses on the strength of thestabilised volume and assumes that the binder has cured.The R&D project ASSERT focuses on quality control using electrical resistivitytomography (ERT). The idea is to use the method in immediate connection with themixing of binders to delineate the soil volume that has been treated with binders fromuntreated parts. ERT could then be used to quickly check the results of thestabilisation, so that supplementary measures can be taken in zones of insufficienttreatment while personnel and equipment are in place. Furthermore, there is potentialfor volume-wide quantification of strength growth via correlation between change inresistivity and change in strength during the curing process, but this would probablyneed to be done on a site specific basis.Testing and verification of the method takes place in different geomaterials in thelaboratory and in the field, including full-scale tests for different types ofstabilisations. Furthermore, method development and adaptation for the applicationare included, so that the method becomes sufficiently robust and fast to be usedroutinely in a sustainable manner. Field trials have been carried out by installingelectrodes in lime-cement columns and jet columns in direct connection to thestabilisation. Laboratory tests have so far been carried out for lime-cementstabilisation of clay and for stabilisation of dredged masses.
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| 5. |
- Elbakidze, Marine, et al.
(författare)
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Multiple factors shape the interaction of people with urban greenspace : Sweden as a case study
- 2022
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Ingår i: Urban Forestry & Urban Greening. - : Elsevier BV. - 1618-8667 .- 1610-8167. ; 74
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Tidskriftsartikel (refereegranskat)abstract
- This study identifies and analyses multiple factors that impact people's interactions with urban greenspace in Sweden. An unrestricted, self-selected online survey was used to collect the data. The survey questions were related to individual characteristics of respondents, including socio-demographic characteristics, self-reported nature connectedness, and self-reported constraints to greenspace usage; perceived characteristics of urban greenspace, including its availability, quality, and accessibility, and benefits and problems; and preferences of respondents regarding types of urban greenspace and activities. Additionally, several spatially explicit variables were included in the analysis. A total of 2806 respondents from 208 (of 290) municipalities completed the survey. Our findings indicate that greenspace users are highly heterogeneous and utilise diverse green spaces along the urban-peri-urban gradient for various benefits. The statistical analyses identified 61 explanatory variables that affect the frequency of interactions with urban greenspace. In addition, we identify key factors that shape critical differences between frequent and infrequent urban users, such as nature connectedness, perceptions of urban greenspace functions, and their perceived accessibility. Our results highlight the complex challenge facing urban planners and managers of green spaces, who have to consider and integrate a vast array of factors influencing the willingness of increasingly diverse urban populations to interact with greenspace.
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| 6. |
- Flodbring Larsson, Per, et al.
(författare)
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FcγRIIIa receptor interacts with androgen receptor and PIP5K1α to promote growth and metastasis of prostate cancer
- 2022
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Ingår i: Molecular Oncology. - : John Wiley & Sons. - 1574-7891 .- 1878-0261.
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Tidskriftsartikel (refereegranskat)abstract
- Low-affinity immunoglobulin gamma Fc region receptor III-A (FcγRIIIa) is a cell surface protein that belongs to a family of Fc receptors that facilitate the protective function of the immune system against pathogens. However, the role of FcγRIIIa in prostate cancer (PCa) progression remained unknown. In this study, we found that FcγRIIIa expression was present in PCa cells and its level was significantly higher in metastatic lesions than in primary tumors from the PCa cohort (P = 0.006). PCa patients with an elevated level of FcγRIIIa expression had poorer biochemical recurrence (BCR)-free survival compared with those with lower FcγRIIIa expression, suggesting that FcγRIIIa is of clinical importance in PCa. We demonstrated that overexpression of FcγRIIIa increased the proliferative ability of PCa cell line C4-2 cells, which was accompanied by the upregulation of androgen receptor (AR) and phosphatidylinositol-4-phosphate 5-kinase alpha (PIP5Kα), which are the key players in controlling PCa progression. Conversely, targeted inhibition of FcγRIIIa via siRNA-mediated knockdown or using its inhibitory antibody suppressed growth of xenograft PC-3 and PC-3M prostate tumors and reduced distant metastasis in xenograft mouse models. We further showed that elevated expression of AR enhanced FcγRIIIa expression, whereas inhibition of AR activity using enzalutamide led to a significant downregulation of FcγRIIIa protein expression. Similarly, inhibition of PIP5K1α decreased FcγRIIIa expression in PCa cells. FcγRIIIa physically interacted with PIP5K1α and AR via formation of protein-protein complexes, suggesting that FcγRIIIa is functionally associated with AR and PIP5K1α in PCa cells. Our study identified FcγRIIIa as an important factor in promoting PCa growth and invasion. Further, the elevated activation of FcγRIII and AR and PIP5K1α pathways may cooperatively promote PCa growth and invasion. Thus, FcγRIIIa may serve as a potential new target for improved treatment of metastatic and castration-resistant PCa.
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| 7. |
- Hedblom, Marcus, et al.
(författare)
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Landscape perception : linking physical monitoring data to perceived landscape properties
- 2020
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Ingår i: Landscape research. - : Routledge. - 0142-6397 .- 1469-9710. ; 45:2, s. 179-192
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Tidskriftsartikel (refereegranskat)abstract
- Changes in the landscape affect not only people’s well-being but also how people perceive and use the landscape. An increasing number of policies have highlighted the importance of conserving a landscape’s recreational and aesthetical values. This study develops and evaluates a model that links people’s perceptions of a mountain landscape to physical monitoring data. Using a questionnaire, we revealed how respondents working with the Swedish mountains characterise the Magnificent Mountain landscape (as defined by Swedish policy objectives) and translated these characteristics into data from the National Inventory of Landscapes in Sweden (NILS). We found 14 potential indicators that could be derived from the existing NILS physical monitoring data and which could be used to monitor changes in the landscape values as perceived by people. Based on the results, we suggest how to simultaneously utilise field sampling of physical data and field photos to provide temporal information about landscape perception.
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| 8. |
- Ignatieva, Maria, et al.
(författare)
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Lawn as a cultural and ecological phenomenon : A conceptual framework for transdisciplinary research
- 2015
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Ingår i: Urban Forestry & Urban Greening. - : Elsevier GmbH. - 1618-8667 .- 1610-8167. ; 14:2, s. 383-387
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Tidskriftsartikel (refereegranskat)abstract
- Globalisation and urbanisation are driving the worldwide homogenisation of urban landscapes. The flora and fauna of cities in different parts of the world are very similar, irrespective of geography and climate. One of the most powerful symbols of modern urban landscapes is the lawn. There are just a few management options for urban lawns, regardless of how they are used and where in the city they are situated. Today, lawns occupy much of the green open spaces in cities (70-75%) and are located in private front and rear gardens, public parks, cemeteries, golf courses and along roads. Most people in the Western world view lawns as a 'natural' and even compulsory element of the urban landscape, without questioning their social, symbolic, ecological or aesthetic values. In this article we discuss the conceptual framework and methodological approaches being used in an ongoing transdisciplinary collaboration project including stakeholders to study lawns in Sweden as a social and ecological phenomenon. The overall aim is to understand the role of lawns in sustainable urban planning, design and management. The transdisciplinary approach allows us to exchange knowledge between scientific disciplines in order to influence the studies within each subject throughout the project and to achieve a multi-dimensional understanding of the lawn as a phenomenon. The involvement and close collaboration of stakeholders in the project allows us to obtain first-hand information on planning issues connected to lawns and existing planning data from cities and to focus on true implementation aspects rather than just theoretical recommendations.
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| 9. |
- Ignatieva, Maria, et al.
(författare)
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The lawn as a social and cultural phenomenon in Sweden
- 2017
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Ingår i: Urban Forestry & Urban Greening. - : Elsevier BV. - 1618-8667 .- 1610-8167. ; 21, s. 213-223
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Tidskriftsartikel (refereegranskat)abstract
- Lawns have a significant influence on the cityscape as one of the essential elements of green spaces and an important part of people's everyday lives. Most people in the Western world view lawns as a compulsory element of the urban landscape, almost an icon, without questioning their social, symbolic, ecological or aesthetic values. This research is a part of the conceptual framework and methodological approaches that are being used in an ongoing transdisciplinary collaboration project to study lawns in Sweden as a social and ecological phenomenon.The overall aim of this study was to investigate social and cultural perceptions of lawns, as well as motives behind decisions about the establishment and management of lawns in Sweden. Two multifamily housing typologies, the 'Million Programme' and People's Homes', were examined due to their dominance in Swedish cities. We also studied how an alternative vision of conventional lawns can be applied and accepted by urban residents. We estimated lawn cover in multi-family housing areas and links to people's perception and use of lawns. Questionnaires, semi-structured interviews and observational studies were used (N = 300). Our results showed that people like lawns even if they do not always directly use them. Lawns cover the most significant amount of outdoor spaces in all multi-family residential areas and accompany people everywhere from the house to the schoolyard or park. The total lawn cover in the study areas was 27.8%. Lawns were particularly valued as important places for different outdoor activities (playing, resting, picnicking, walking, socialising) and enjoying the green colour. However people do not want to use a vast monotonous lawn, but a variety of spaces that provide good conditions for different senses ( sound, smell, touch and sight) and activities. Alternative lawns were also appreciated by many citizens, politicians, planners and managers. The implementation of new types of lawns requires special planning and design solutions adjusted for each particular neighbourhood. (C) 2016 The Authors. Published by Elsevier GmbH.
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| 10. |
- Johansson, Sara, et al.
(författare)
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Spectral analysis of time domain induced polarization waveforms
- 2020
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Ingår i: Journal of Applied Geophysics. - : Elsevier BV. - 0926-9851. ; 177
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Tidskriftsartikel (refereegranskat)abstract
- Spectral induced polarization is a well-established geophysical method that can be measured in both time- and frequency domain. Time- and frequency domain methods are theoretically equivalent via the Fourier transform. However, data acquisition parameters such as the sampling frequency and pulse length affect the actual spectral content of real time domain waveforms. Comparative studies showing the practical equivalence of time- and frequency domain measurements are few and have been carried out using various approaches. Some of these studies concluded that it is not possible to resolve wide band spectral information with time domain waveforms. The few studies available presenting actual spectral analysis of time domain signals were carried out several decades ago on field data with limited data acquisition- and/or analysis methods. There is, therefore, a need to re-evaluate the possible spectral range of time domain induced polarization data considering modern instrument development during the last decades. In addition, there is a need to verify the physical importance of factors such as spectral energy distribution and measurement noise, which previously have been assumed to inherently limit the spectral content of time domain waveforms. In this study, the discrete Fourier transform is applied to analyze the spectral content of synthetic time domain waveforms with different data acquisition parameters and noise. The results are presented as the frequency domain parameters amplitude and phase and compared to the corresponding frequency domain Debye model. To study the effect of noise, a spectral analysis of synthetic full waveform data contaminated with Gaussian noise is also provided, where the noise level were guided by an example of measured field data. Finally, laboratory TD IP measurements were performed on a test circuit, transformed to the frequency domain and compared to the theoretical response of the circuit in terms of the FD IP parameters amplitude and phase. The results illustrate that spectral information contained in the time domain waveform is, as expected, limited by the fundamental frequency of the square wave at low frequencies and the sampling frequency at high frequencies. Variation of the relaxation time shows that the ability to correctly resolve high frequency relaxations is also dependent on the sampling frequency. Furthermore, the result show that high frequency noise might distort the frequency domain representation. However, this noise can be filtered away prior to the spectral analysis, which significantly improves the resolution in frequency domain. The results of this study is in contradiction to earlier studies stating that the spectral range of time domain waveforms is inherently narrow due to the domination of the fundamental frequency over the higher harmonics. The main reason is that the relative spectral energy of different harmonics is of no importance in time domain measurements; in contrast to frequency domain measurements, the total polarization of all length scales are excited simultaneously. The results and discussion in this study are expected to contribute to an improved comprehension of the spectral range that can be achieved with time domain induced polarization data collected with modern instruments.
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