| 1. |
- Tengblad, Olof, 1957, et al.
(författare)
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LaBr3(Ce):LaCl3(Ce) Phoswich with pulse shape analysis for high energy gamma-ray and proton identification
- 2013
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Ingår i: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - : Elsevier BV. - 0168-9002. ; 704:0, s. 19-26
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Tidskriftsartikel (refereegranskat)abstract
- A novel Phoswich design based on new generation scintillator crystals is presented. The detector composed from a combination of a LaBr3(Ce) with a LaCl3(Ce) crystal in one cylinder coupled to a photo multiplier tube has been tested both for incident gamma rays in the range of 0.3–6 MeV, as well as for high energy protons in the range 120–180 MeV. The Phoswich assembly has not significantly deteriorated the energy resolution, which for 662 KeV gamma rays gives a resolution of 4.5%, while for high energy protons (Ep=180 MeV) an energy resolution of 1% was obtained. It is shown that the signals from the two crystals can be separated in an event by event based mode. Using direct digitizing of the detector pulse an off-line pulse-shape analysis was performed built either on a total to tail or total to pulse height method in order to fully identify the incoming radiation. Our aim with this R&D is to in the future build a detector which is able to detect with good efficiency and resolution over a wide energy range; 0.1–30 MeV gamma rays and 20–400 MeV protons. Monte Carlo simulations made in order to design the next prototype are presented.
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| 2. |
- Tengblad, O., et al.
(författare)
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Phoswich scintillator for proton and gamma radiation of high energy
- 2011
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Ingår i: AIP Conference Proceedings. - : AIP. - 1551-7616 .- 0094-243X. - 9780735409835 ; 1409, s. 141-144
-
Konferensbidrag (refereegranskat)abstract
- We present here a Phoswich scintillator design to achieve both high resolution gamma ray detection, and good efficiency for high energy protons. There are recent developments of new high resolution scintillator materials. Especially the LaBr3(Ce) and LaCl3(Ce) crystals have very good energy resolution in the order of 3% for 662 keV gamma radiation. In addition, these materials exhibit a very good light output (63 and 32 photons/keV respectively). A demonstrator detector in the form of an Al cylinder of 24 mm diameter and a total length of 80 mm with 2 mm wall thickness, containing a LaBr3(Ce) crystal of 20 mm diameter and 30 mm length directly coupled to a LaCl3(Ce) crystal of 50 mm length, and closed with a glass window of 5 mm, was delivered by Saint Gobain. To the glass window a Hamamatsu R5380 Photomultiplier tube (PMT) was coupled using silicon optical grease. © 2011 American Institute of Physics.
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| 3. |
-
- 2019
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Tidskriftsartikel (refereegranskat)
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| 4. |
- Lembrechts, Jonas J., et al.
(författare)
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Global maps of soil temperature
- 2022
-
Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 28:9, s. 3110-3144
-
Tidskriftsartikel (refereegranskat)abstract
- Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean=3.0±2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6±2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7±2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.
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| 5. |
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| 6. |
- Nilsson, Johan, 1987, et al.
(författare)
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Chemistry of supported palladium nanoparticles during methane oxidation
- 2015
-
Ingår i: ACS Catalysis. - : American Chemical Society (ACS). - 2155-5435. ; 5:4, s. 2481-2489
-
Tidskriftsartikel (refereegranskat)abstract
- Time-resolved in situ energy-dispersive X-ray absorption spectroscopy and mass spectrometry are used to correlate changes in chemical state of alumina and ceria supported palladium nanoparticles with changes in activity and selectivity for methane oxidation. Specifically, modulation excitation spectroscopy experiments are carried out by periodically cycling between net-reducing and net-oxidizing reaction conditions. The XANES and EXAFS data show that the palladium nanoparticles are readily bulk oxidized when exposed to oxygen, forming a PdO-like phase, and reduced back to a reduced (metal) phase when oxygen is removed from the feed. The difference between the two support materials is most noticeable at the switches between net-oxidizing and net-reducing reaction conditions. Here, a brief reduction in conversion is observed for the alumina supported catalyst, but for the ceria this reduction in conversion is minor or not observed at all. This difference is attributed to differences in the oxidation kinetics and the oxygen storage capability of ceria.
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| 7. |
- Rydberg Sterner, Therese, et al.
(författare)
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The Gothenburg H70 Birth cohort study 2014-16: design, methods and study population.
- 2019
-
Ingår i: European journal of epidemiology. - : Springer Science and Business Media LLC. - 1573-7284 .- 0393-2990. ; 34:2, s. 191-209
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Tidskriftsartikel (refereegranskat)abstract
- To improve health care for older persons, we need to learn more about ageing, e.g. identify protective factors and early markers for diseases. The Gothenburg H70 Birth Cohort Studies (the H70 studies) are multidisciplinary epidemiological studies examining representative birth cohorts of older populations in Gothenburg, Sweden. So far, six birth cohorts of 70-year-olds have been examined over time, and examinations have been virtually identical between studies. This paper describes the study procedures for the baseline examination of the Birth cohort 1944, conducted in 2014-16. In this study, all men and women born 1944 on specific dates, and registered as residents in Gothenburg, were eligible for participation (n=1839). A total of 1203 (response rate 72.2%; 559 men and 644 women; mean age 70.5years) agreed to participate in the study. The study comprised sampling of blood and cerebrospinal fluid, psychiatric, cognitive, and physical health examinations, examinations of genetics and family history, use of medications, social factors, functional ability and disability, physical fitness and activity, body composition, lung function, audiological and ophthalmological examinations, diet, brain imaging, as well as a close informant interview, and qualitative studies. As in previous examinations, data collection serves as a basis for future longitudinal follow-up examinations. The research gained from the H70 studies has clinical relevance in relation to prevention, early diagnosis, clinical course, experience of illness, understanding pathogenesis and prognosis. Results will increase our understanding of ageing and inform service development, which may lead to enhanced quality of care for older persons.
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| 8. |
- Wang, Xueting, 1991, et al.
(författare)
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Copper-modified zeolites and silica for conversion of methane to methanol
- 2018
-
Ingår i: Catalysts. - : MDPI AG. - 2073-4344. ; 8:11
-
Tidskriftsartikel (refereegranskat)abstract
- Powder materials containing copper ions supported on ZSM-5 (Cu-Zeolite Socony Mobil-5) and SSZ-13 (Cu-Standard Oil synthesised zeolite-13), and predominantly CuO nanoparticles on amorphous SiO2 were synthesised, characterised, wash-coated onto ceramic monoliths and, for the first time, compared as catalysts for direct conversion of methane to methanol (DCMM) at ambient pressure (1 atm) using O2, N2 O and NO as oxidants. Methanol production was monitored and quantified using Fourier transform infrared spectroscopy. Methanol is formed over all monolith samples, though the formation is considerably higher for the copper-exchanged zeolites. Hence, copper ions are the main active sites for DCMM. The minor amount of methanol produced over the Cu/SiO2 sample, however, suggests that zeolites are not the sole substrate that can host those active copper sites but also silica. Further, we present the first ambient pressure in situ infrared spectroscopic measurements revealing the formation and consumption of surface methoxy species, which are considered to be key intermediates in the DCMM reaction.
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| 9. |
- Wang, Xueting, 1991, et al.
(författare)
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Methanol Desorption From Cu-ZSM-5 Studied by In Situ Infrared Spectroscopy and First-Principles Calculations
- 2017
-
Ingår i: Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 121:49, s. 27389-27398
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Tidskriftsartikel (refereegranskat)abstract
- The dynamic interaction of methanol and its derivatives with Cu-exchanged ZSM- 5 during methanol temperature programmed desorption from 30 to 450 ◦C has been investigated using in situ diffuse reflectance infrared Fourier transform spectroscopy and first-principles calculations. The results emphasize that defects in the framework structure of the zeolite and Brønsted acid sites constitute ion-exchange sites for Cu ions. The Cu sites introduced in ZSM-5 actively interact with methanol adsorbed at moderate temperature, i.e. below 250◦C, and take roles in further oxidation of the adsorbed species to formate and CO. Moreover, spectra recorded at higher temperatures, i.e. above 300◦C, after adsorption of methanol show strong interaction between methoxy groups and the zeolite framework, suggesting that under mild conditions proton extraction for methanol production during direct partial oxidation of methane to methanol over Cu-ZSM-5 is necessary.
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| 10. |
- Adams, Emma, 1989, et al.
(författare)
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The chemistry of the palladium phase in Pd/Ce/Al2O3 during ammonia formation
- 2016
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The formation of NH3 from NO is a crucial reaction for passive-selective catalytic reduction applications. In this application, an in situ supply of NH3 is formed in oxygen-lean conditions, which can subsequently be used to reduce NO to N2 in the presence of excess O2 [1]. On the fundamental level, producing NH3 from NO through heterogeneous catalytic processes involves fascinating surface chemistry that is not yet well understood. In the presence of stoichiometric and excess oxygen concentrations, NH3 formation is suppressed. However, we have previously shown that Pd/Ce/Al2O3 is a promising formulation, able to temporarily facilitate the formation of ammonia under globally slightly-oxidizing but locally rich conditions [2].This work uses in situ X-ray absorption spectroscopy (XAS) to identify how the oxidation state of the catalytically active phase is affected during transient pulses of O2 in the presence of either pure NO or a combination of NO, CO and H2.
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| 11. |
- Bernson, Elin, 1987, et al.
(författare)
-
Cytomegalovirus Serostatus Affects Autoreactive NK Cells and Outcomes of IL2-Based Immunotherapy in Acute Myeloid Leukemia
- 2018
-
Ingår i: Cancer Immunology Research. - : American Association for Cancer Research (AACR). - 2326-6066 .- 2326-6074. ; 6:9, s. 1110-1119
-
Tidskriftsartikel (refereegranskat)abstract
- Human cytomegalovirus (CMV) infection is reported to promote NK cell differentiation and education. The CMV-induced generation of highly differentiated adaptive-like NK cells has been proposed to affect favorably on the maintenance of remission in patients with acute myeloid leukemia (AML) after allogeneic stem cell transplantation (allo-SCT). The impact of CMV infection and adaptive-like NK cells on relapse and survival of patients with AML not receiving allo-SCT remains unknown. We assayed CMV IgG serostatus to determine past CMV infection in 81 nontransplanted AML patients who were receiving relapse-prevention immunotherapy comprising histamine dihydrochloride and low-dose interleukin-2 (HDC/IL2; NCT01347996). CMV seropositivity correlated negatively with leukemia-free and overall survival of patients receiving HDC/IL2, but did not correlate with outcomes in a contemporary control cohort. Analysis of outcome after stratification of patients based on concordant or discordant killer immunoglobulin-like receptor (KIR) and HLA genotypes implied that the negative impact of CMV seropositivity was restricted to patients lacking a ligand to inhibitory KIRs (iKIR). Previous CMV infection was also associated with fewer NK cells expressing only nonself iKIRs (NS-iKIR). We propose that CMV-driven NK cell education depletes the population of NS-iKIR NK cells, which in turn reduces the clinical benefit of relapse-preventive immunotherapy in AML.
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| 12. |
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| 13. |
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| 14. |
- Hamnerius, Yngve, 1950, et al.
(författare)
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Design of Safe Wireless Power Transfer Systems for Electric Vehicles
- 2018
-
Ingår i: 2018 2nd URSI Atlantic Radio Science Meeting, AT-RASC 2018. - 9789082598735
-
Konferensbidrag (refereegranskat)abstract
- Wireless charging of electric vehicles is convenient but in order to make it safe the exposure of humans to electromagnetic fields must be below acceptable limits. We have designed a prototype system that transmits 3 kW with an efficiency of 85% where the magnetic fields around and inside the vehicle are below the EU council recommendation of 6.25μT at 85 kHz.
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| 15. |
- Martin, Natalia Mihaela, 1984, et al.
(författare)
-
A LEIS and in situ XAS study of supported Pd-Pt catalysts for CH4 oxidation
- 2016
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- It is of vital importance to remove methane (CH4) from the exhausts of natural gas and biogas fueled engines as CH4 is a strong greenhouse gas. So far Pd-based catalysts have been used almost exclusively but their high sensitivity to sulfur and water pushes research to explore other materials. Among these are Pd-Pt catalysts [1-4], which exhibit a slight increase in CH4 oxidation activity with time and higher long-term stability than the Pd-only counterpart [5-7]. Still, however, little is known about the oxidation-reduction behaviour of the Pd-Pt nanoclusters and how this impacts the catalytic activity. This study aims at increase the understanding of the catalytic activity of Al2O3-supported Pd-Pt nanoclusters for low-temperature CH4 oxidation under transient, although generally lean, conditions.
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| 16. |
- Martin, Natalia Mihaela, 1984, et al.
(författare)
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Characterization of Surface Structure and Oxidation/Reduction Behaviour of Pd-Pt/Al2O3 Model Catalysts
- 2016
-
Ingår i: Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 120:49, s. 28009-28020
-
Tidskriftsartikel (refereegranskat)abstract
- Structural and morphological characterisation of bimetallic Pd-Pt/Al2O3 model cat- alysts are performed using X-ray diffraction, X-ray absorption spectroscopy, transmis- sion electron microscopy and CO chemisorption. Further, the catalysts were studied under oxidising and reducing conditions using both X-ray absorption spectroscopy and low-energy ion scattering spectroscopy. For the as-prepared catalysts, the existence of alloyed bimetallic Pd-Pt particles and of (tetragonal) PdO were found for the samples calcined at 800 C. PdO is present in form of crystals at the surface of the Pd-Pt par- ticles or as isolated PdO crystals on the support oxide. Bimetallic Pd-Pt nanoparticles were only formed on the Pd-Pt catalysts after calcination at 800 C. The results show that the Pd-Pt nanoparticles undergo reversible changes in surface structure composi- tion and chemical state in response to oxidising or reducing conditions. Under oxidising conditions Pd segregates to the shell and oxidises forming PdO, while under reducing conditions regions with metallic Pd and Pd-Pt alloys were observed at the surface. No bimetallic Pd-Pt nanoparticles were observed for the sample initially calcined at 500 C, but instead isolated monometallic particles, where small Pt particles are easily oxidised under O2 treatment. In the monometallic catalysts, the Pd is found to be com- pletely oxidised already after calcination and to consist of metallic Pd after reductive treatment.
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| 17. |
- Martin, Natalia Mihaela, 1984, et al.
(författare)
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Study of methane oxidation over alumina supported Pd-Pt catalysts using operando DRIFTS/MS and in situ XAS techniques
- 2017
-
Ingår i: Catalysis, Structure and Reactivity. - 2055-0758. ; 3:1-2, s. 24-32
-
Tidskriftsartikel (refereegranskat)abstract
- Methane oxidation over Pd–Pt/Al2O3 model catalysts calcined at three different conditions is investigated using operando diffuse reflectance infrared Fourier transform spectroscopy and mass spectrometry, and in situ X-ray absorption spectroscopy while cycling the feed gas stoichiometry between lean (net-oxidising) and rich (net-reducing) conditions. When calcined in air, alloy Pd–Pt nanoparticles are present only on catalysts subjected to elevated temperature (800 ◦C) whereas calcination at lower temperature (500◦C) leads to segregated Pt and Pd nanoparticles on the support. Here, we show that the alloy Pd–Pt nanoparticles undergo reversible changes in surface structure and composition during transient methane oxidation exposing a PdO surface during lean conditions and a metallic Pd–Pt surface (Pd enriched) under rich conditions. Alloyed particles seem more active for methane oxidation than their monometallic counterparts and, furthermore, an increased activity for methane oxidation is clearly observed under lean conditions when PdO has developed on the surface, analogous to monometallic Pd catalysts. Upon introducing rich conditions, partial oxidation of methane dominates over total oxidation forming adsorbed carbonyls on the noble metal particles. The carbonyl spectra for the three samples show clear differences originating from different surfaces exposed by alloyed vs. non-alloyed particles. The kinetics of the noble metal oxidation and reduction processes as well as carbonyl formation during transient methane oxidation are discussed.
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| 18. |
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| 19. |
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| 20. |
- Nilsson, Johan, 1987, et al.
(författare)
-
First Principles Calculations of Palladium Nanoparticle XANES Spectra
- 2017
-
Ingår i: Topics in Catalysis. - : Springer Science and Business Media LLC. - 1572-9028 .- 1022-5528. ; 60:3-5, s. 283-288
-
Tidskriftsartikel (refereegranskat)abstract
- X-ray absorption spectroscopy is a common technique for in situ studies of catalysts. The interpretation of the near edge structure is, however, often hampered by lack of information of how structural and electronic contributions affect the spectra. Here, first principles calculations were used to explore effects of particle size, structural motif and oxidation state on the X-ray absorption near edge structure (XANES) for palladium nanoparticles (PdNP). A range of PdNP were structurally optimized within the density function theory and Pd K edge XANES spectra were calculated using the real-space multiple-scattering formalism. The results show that the Pd-Pd distances are compressed for small NP which yields shifts in the XANES peak positions as compared to bulk Pd. Moreover, the amplitude of the fine structure oscillations is found to increase with the average coordination number. The spectra are only to a minor extent influenced by the structural motif of the PdNP. Oxidation of the Pd surface increases the intensity in the XANES spectrum between the first and the second absorption feature, which correspond to the initial development of a whiteline peak. It is found that a strong whiteline peak only is developed for Pd-atoms with complete oxidation, which corresponds to coordination to four oxygen atoms.
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| 21. |
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| 22. |
- Nilsson, Johan, 1987, et al.
(författare)
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Methane oxidation over Pd/Al2O3 under rich/lean cycling followed by operando XAFS and modulation excitation spectroscopy
- 2017
-
Ingår i: Journal of Catalysis. - : Elsevier BV. - 0021-9517 .- 1090-2694. ; 356, s. 237-245
-
Tidskriftsartikel (refereegranskat)abstract
- Rich/lean cycling is used to study the total oxidation of methane over a Pd/Al2O3 catalyst at different oxi- dation states. Time-resolved energy-dispersive X-ray absorption fine structure is used in a modulation excitation approach to monitor the chemical state of the palladium nanoparticles during the cycling, and the resulting spectra are demodulated using phase sensitive detection. Cycling is performed using oxygen pulses with a concentration of 0.15, 0.25, and 1.5% over a constant flow of 0.1% methane. For the two lowest oxygen concentrations the methane conversion is generally low but increases at the switches between the rich and the lean periods, while for the highest oxygen concentration the conver- sion is highest during the lean periods. The oxidation state of Pd changes rapidly but to a limited extent for the two lowest oxygen concentrations, whereas for the high oxygen concentration the oxidation appears to proceed via a two-step process, where the first step is rapid and the second step is slower. EXAFS fitting of the demodulated spectra is used to quantify the Pd oxidation state, the first rapid oxida- tion step is assigned to surface oxidation, while the second step is assigned to bulk oxidation of Pd. A low methane conversion is observed when the Pd nanoparticles are covered with chemisorbed oxygen or sur- face oxide, the methane conversion is higher when the Pd nanoparticles are bulk oxidized.
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| 23. |
- Nilsson, Johan, 1987
(författare)
-
Operando X-ray Absorption Spectroscopy Studies of Methane Oxidation Catalysts
- 2017
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Operando spectroscopy is an experimental method in catalysis that combines measurements of catalytic activity and selectivity with simultaneous in situ spectroscopic characterization of the catalyst. Since the structure and composition of the catalyst are probed under reaction conditions, the method can provide valuable information to elucidate the mechanism of the studied reaction. In this thesis, operando spectroscopy has been performed using X-ray absorption fine structure (XAFS) as an in situ characterization technique to study catalysts during the total oxidation of methane. Methane is a strong greenhouse gas and catalytic oxidation can be used, for example, to remove uncombusted methane from the exhausts of vehicles fueled with natural gas or biogas. Palladium is the most active metal for the total oxidation of methane, but the oxidation state of palladium can change rapidly during reaction conditions, which has an effect on the catalytic activity. Time-resolved XAFS was used to investigate Pd/Al2O3 catalysts under transiently changing reaction conditions for methane oxidation, by performing oxygen pulse-response experiments, so the conditions periodically change from net-reducing to net-oxidizing. Simultaneously, the outlet concentrations of reactants and products were monitored with mass spectrometry. The XAFS data show that palladium in the catalyst is readily reduced and oxidized when the feed gas composition is changed from reducing to oxidizing. The highest activity for methane oxidation is found over bulk-oxidized palladium (PdO), while surface oxidized palladium in comparison is less active. Similar experiments were also performed for a Pd/CeO2 catalyst. Compared to the alumina supported catalyst, palladium supported on CeO2 is oxidized more rapidly in an oxidizing atmosphere, and is reduced at a slower rate in a reducing atmosphere. This shows that CeO2 is able to stabilize Pd in the oxidized state which, could be beneficial for the methane oxidation activity. Moreover, methane oxidation under cycling conditions was investigated for bimetallic Pd-Pt/Al2O3 catalysts. Pd-Pt catalysts have attracted interest due their higher long-term stability compared to Pd-only catalysts. In our studies we found that the calcination temperature during catalyst preparation is of high importance for the morphology of the catalysts. For catalysts calcined at 500°C, Pd and Pt are not alloyed but are found as separate Pd and Pt nanoparticles. However, for catalysts calcined at 800°C alloyed Pd-Pt nanoparticles are found as well as monometallic Pd nanoparticles. The methane conversion was higher over the alloyed Pd-Pt nanoparticles calcined at 800°C. In similarity to the Pd-only catalyst, high activity for methane oxidation is connected to a high amount of oxidized palladium in the catalyst. Although XAFS is only available at synchrotron light sources, the ability to investigate the active phase of catalysts with high time resolution, under reaction conditions, makes it a highly useful technique in catalysis research.
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| 24. |
- Nilsson, Johan, 1987, et al.
(författare)
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Oxygen step-response experiments for methane oxidation over Pd/Al2O3: An in situ XAFS study
- 2018
-
Ingår i: Catalysis Communications. - : Elsevier BV. - 1566-7367. ; 109, s. 24-27
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Tidskriftsartikel (refereegranskat)abstract
- Methane oxidation over Pd/Al2O3 has been investigated by in situ XAFS characterization during oxygen step-response experiments. With a net-reducing feed gas, Pd is in a reduced state and the introduction of oxygen leads to oxidation of palladium as well as increased methane conversion. When the rate of Pd oxidation is slow, a transient surface oxidized state is observed with low activity for methane oxidation. The activity increases when palladium is further oxidized and the highest activity is observed for palladium oxide.
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| 25. |
- Nilsson, P., et al.
(författare)
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Modelling the effect on injuries and fatalities when changing mode of transport from car to bicycle
- 2017
-
Ingår i: Accident Analysis and Prevention. - : Elsevier BV. - 0001-4575. ; 100, s. 30-36
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Several studies have estimated the health effects of active commuting, where a transport mode shift from car to bicycle reduces risk of mortality and morbidity. Previous studies mainly assess the negative aspects of bicycling by referring to fatalities or police reported injuries. However, most bicycle crashes are not reported by the police and therefore hospital reported data would cover a much higher rate of injuries from bicycle crashes. The aim of the present study was to estimate the effect on injuries and fatalities from traffic crashes when shifting mode of transport from car to bicycle by using hospital reported data. Methods: This present study models the change in number of injuries and fatalities due to a transport mode change using a given flow change from car to bicycle and current injury and fatality risk per distance for bicyclists and car occupants. Results: show that bicyclists have a much higher injury risk (29 times) and fatality risk (10 times) than car occupants. In a scenario where car occupants in Stockholm living close to their work place shifts transport mode to bicycling, injuries, fatalities and health loss expressed in Disability-Adjusted Life Years (DALY) were estimated to increase. The vast majority of the estimated DALY increase was caused by severe injuries and fatalities and it tends to fluctuate so that the number of severe crashes may exceed the estimation with a large margin. Conclusion: Although the estimated increase of traffic crashes and DALY, a transport mode shift is seen as a way towards a more sustainable society. Thus, this present study highlights the need of strategic preventive measures in order to minimize the negative impacts from increased bicycling. (C) 2016 Elsevier Ltd. All rights reserved.
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| 26. |
- Rasilainen, Kimmo, 1987, et al.
(författare)
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Thermal analysis of GaN/SiC-on-Si assemblies: Effect of bump pitch and thickness of SiC Layer
- 2020
-
Ingår i: 2020 26th International Workshop on Thermal Investigations of ICs and Systems, THERMINIC 2020 - Proceedings.
-
Konferensbidrag (refereegranskat)abstract
- The ever-increasing requirements for high device performance and compact size drive the communications industry to lookfor new materials, technologies, and integration concepts. This simulation-based study investigates the thermal properties of a compact, heterogeneously integrated gallium nitride on silicon carbide (GaN-on-SiC) and silicon (Si) assembly. Thermal simulations and parametric studies are used to determine how the heat spreading and temperature levels in the lateral and vertical directions are affected by the thickness of the SiC layer and the distribution of the thermal interconnects. Results show that a SiC layer thinned down to 100 μm shows more pronounced differences in its thermal characteristics compared to thicker ones, especially in terms of its backside heating. Aspects related to practical implementations are also considered.
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| 27. |
- Sandblom, Viktor, 1987, et al.
(författare)
-
Gemcitabine potentiates the anti-tumour effect of radiation on medullary thyroid cancer.
- 2019
-
Ingår i: PloS One. - : Public Library of Science (PLoS). - 1932-6203. ; 14:11
-
Tidskriftsartikel (refereegranskat)abstract
- Patients with medullary thyroid cancer (MTC) are often diagnosed with spread tumour disease and the development of better systemic treatment options for these patients is important. Treatment with the radiolabelled somatostatin analogue 177Lu-octreotate is already a promising option but can be optimised. For example, combination treatment with another substance could increase the effect on tumour tissue. Gemcitabine is a nucleoside analogue that has been shown to sensitise tumour cells to radiation. The aim of this study was to investigate potentially additive or synergistic effects of combining radiation with gemcitabine for treatment of MTC. Nude mice transplanted with patient-derived MTC tumours (GOT2) were divided into groups and treated with radiation and/or gemcitabine. Radiation treatment was given as 177Lu-octreotate or external beam radiotherapy (EBRT). The volume of treated and untreated tumours was followed. The absorbed dose and amount of gemcitabine were chosen to give moderate tumour volume reduction when given as monotherapy to enable detection of increased effects from combination treatment. After follow-up, the mice were killed and tumours were immunohistochemically (IHC) analysed. Overall, the animals that received a combination of EBRT and gemcitabine showed the largest reduction in tumour volume. Monotherapy with EBRT or gemcitabine also resulted in a clear detrimental effect on tumour volume, while the animals that received 177Lu-octreotate monotherapy showed similar response as the untreated animals. The GOT2 tumour was confirmed in the IHC analyses by markers for MTC. The IHC analyses also revealed that the proliferative activity of tumour cells was similar in all tumours, but indicated that fibrotic tissue was more common after EBRT and/or gemcitabine treatment. The results indicate that an additive, or even synergistic, effect may be achieved by combining radiation with gemcitabine for treatment of MTC. Future studies should be performed to evaluate the full potential of combining 177Lu-octreotate with gemcitabine in patients.
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| 28. |
- Sandblom, Viktor, 1987, et al.
(författare)
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Increased therapeutic effect on medullary thyroid cancer using a combination of radiation and tyrosine kinase inhibitors : Increased effect on medullary thyroid cancer by combining radiation with tyrosine kinase inhibitors
- 2020
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 15:5
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Tidskriftsartikel (refereegranskat)abstract
- Since patients with medullary thyroid cancer (MTC) often have metastatic disease at the time of diagnosis, the development of efficient systemic treatment options for MTC is important. Vandetanib and cabozantinib are two tyrosine kinase inhibitors (TKIs) that were recently approved by FDA and EMA for systemic treatment of metastatic MTC. Additionally, since MTC is of a neuroendocrine tumour type, treatment with radiolabelled somatostatin analogues (e.g. 177Lu-octreotate) is a valid option for patients with MTC. The aim of this study was to investigate the potentially increased therapeutic effect of combining radiation therapy with these TKIs for treatment of MTC in a mouse model. Nude mice carrying patient-derived MTC tumours (GOT2) were treated with external beam radiotherapy (EBRT) and/or one of the two TKIs vandetanib or cabozantinib. The tumour volume was determined and compared with that of mock-treated controls. The treatment doses were chosen to give a moderate effect as monotherapy to be able to detect any increased therapeutic effect from the combination therapy. At the end of follow-up, tumours were processed for immunohistochemical (IHC) analyses. The animals in the combination therapy groups showed the largest reduction in tumour volume and the longest time to tumour progression. Two weeks after start of treatment, the tumour volume for these mice was reduced by about 70-75% compared with controls. Furthermore, also EBRT and TKI monotherapy resulted in a clear anti-tumour effect with a reduced tumour growth compared with controls. The results show that an increased therapeutic effect could be achieved when irradiation is combined with TKIs for treatment of MTC. Future studies should evaluate the potential of using 177Lu-octreotate therapy in combination with TKIs in patients.
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| 29. |
- Sandblom, Viktor, 1987, et al.
(författare)
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Radiolabelled pharmaceuticals MIBG and octreotate for treatment of metastatic pheochromocytoma and paraganglioma
- 2014
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Ingår i: SweRays Workshop, Malmö, Sweden, Aug 20-22, 2014.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Background: The 5-year survival for patients with metastatic pheochromocytoma (PC) and paraganglioma (PGL) is less than 50%. There is a clear need for development of better diagnostic and therapeutic options for these patients. Radionuclide therapy offers the possibility to treat spread PC/PGL. The norepinephrine (NE) analogue metaiodobenzylguanidine (MIBG) and the somatostatin (SST) analogues octreotate or octreotide are possible molecules that could be used for this purpose. These analogues have different biodistribution and different organs at risk, when used for therapy. Thus, combined therapy, using both radiolabelled NE and SST analogues, might be beneficial for these patients. Aim: The aim of this study was to evaluate the possibility of using 177Lu-octreotate and/or 131I-MIBG for treatment of patients with metastatic PC/PGL. Materials and Methods: Three patients with metastatic PC/PGL were injected with 131I-MIBG and 111In-octreotide, and four patients with metastatic PC/PGL were injected with 111In-octreotide, before surgical removal of the primary tumour. During surgery, tissue samples of tumour, blood, fat and muscle were collected and weighed, and the radioactivity was measured in a gamma counter. The activity concentration in these tissue samples was then calculated for each radionuclide. Additionally, tumour-to-blood activity concentration ratios (T/B) were calculated. Results: The activity concentrations and T/B values showed large variations between patients. For 111In-octreotide, T/B values were 25-590 and for 131I-MIBG, the corresponding values were 0-1600. Conclusion: The sometimes high T/B values show a clear possibility of using 177Lu-octreotate and 131I-MIBG for treatment of some patients with metastatic PC/PGL. However, due to the large variation between patients, individual investigation of tumour uptake prior to treatment is required.
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| 30. |
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| 31. |
- Sandblom, Viktor, 1987, et al.
(författare)
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Tyrosinkinashämmare kan öka effekten från strålbehandling av medullär tyreoideacancer
- 2019
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Ingår i: Nationellt möte om sjukhusfysik.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- SYFTE Medullär tyreoideacancer (MTC) är en neuroendokrin cancertyp som har sitt ursprung i sköldkörtelns hormonproducerande C-celler. Många MTC överuttrycker receptorer för somatostatin vilket möjliggör radionuklidterapi med exempelvis 177Lu-oktreotat. Få patienter botas dock helt och optimering av behandlingen behövs. Ett sätt att optimera behandlingen är att kombinera 177Lu-oktreotat med ett annat läkemedel i syfte att öka effekten från strålningen. Nyligen godkändes två tyrosinkinashämmare (vandetanib och cabozantinib) för behandling av MTC. Syftet med denna studie var att undersöka ifall en ökad effekt kan fås då strålbehandling kombineras med tyrosinkinashämmare för behandling av MTC. METOD Nakna möss (BALB/c) transplanterades med humana MTC-celler (GOT2) och behandlades med extern strålbehandling och/eller tyrosinkinashämmare. Behandlings-effekten, som tumörvolym efter behandling, jämfördes med den hos obehandlade möss. För att möjliggöra detektion av en eventuellt ökad behandlingseffekt hos de möss som fick kombinationsbehandling (både strålbehandling och tyrosinkinas¬hämmare) valdes den absorberade dosen och mängden läkemedel så att en suboptimal effekt erhölls då respektive behandling gavs som singelbehandling. RESULTAT Kombinationsbehandling resulterade i störst minskning av tumörvolym och längst tid till progression. Exempelvis hade tumörvolymen hos de möss som fick kombinationsbehandling minskat med ca 70-75% efter två veckor jämfört med obehandlade möss. Även som singelbehandling resulterade båda behandlingar i en tydlig effekt på tumörvolymen, med en minskning på ca 50-65% efter två veckor. KONKLUSIONER Effekten från strålbehandling av möss med MTC-tumörer kan ökas genom kombinationsbehandling med tyrosinkinashämmare. Framtida studier bör utvärdera möjligheten att använda en kombination av 177Lu-oktreotat och tyrosinkinashämmare för behandling av patienter med MTC.
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| 32. |
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| 33. |
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| 34. |
- Venkatakrishnan, Vignesh, 1987, et al.
(författare)
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Novel inhibitory effect of galectin-3 on the respiratory burst induced by Staphylococcus aureus in human neutrophils
- 2023
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Ingår i: Glycobiology. - : OXFORD UNIV PRESS INC. - 1460-2423 .- 0959-6658. ; 33:6, s. 503-511
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Tidskriftsartikel (refereegranskat)abstract
- Among the responders to microbial invasion, neutrophils represent the earliest and perhaps the most important immune cells that contribute to host defense with the primary role to kill invading microbes using a plethora of stored anti-microbial molecules. One such process is the production of reactive oxygen species (ROS) by the neutrophil enzyme complex NADPH-oxidase, which can be assembled and active either extracellularly or intracellularly in phagosomes (during phagocytosis) and/or granules (in the absence of phagocytosis). One soluble factor modulating the interplay between immune cells and microbes is galectin-3 (gal-3), a carbohydrate-binding protein that regulates a wide variety of neutrophil functions. Gal-3 has been shown to potentiate neutrophil interaction with bacteria, including Staphylococcus aureus, and is also a potent activator of the neutrophil respiratory burst, inducing large amounts of granule-localized ROS in primed cells. Herein, the role of gal-3 in regulating S. aureus phagocytosis and S. aureus-induced intracellular ROS was analyzed by imaging flow cytometry and luminol-based chemiluminescence, respectively. Although gal-3 did not interfere with S. aureus phagocytosis per se, it potently inhibited phagocytosis-induced intracellular ROS production. Using the gal-3 inhibitor GB0139 (TD139) and carbohydrate recognition domain of gal-3 (gal-3C), we found that the gal-3-induced inhibitory effect on ROS production was dependent on the carbohydrate recognition domain of the lectin. In summary, this is the first report of an inhibitory role of gal-3 in regulating phagocytosis-induced ROS production.
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