| 1. |
- Roxhed, Niclas, et al.
(författare)
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Low-cost uncooled microbolometers for thermal imaging
- 2010
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Ingår i: OPTICAL SENSING AND DETECTION. - : SPIE. - 9780819481993 ; , s. 772611-
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Konferensbidrag (refereegranskat)abstract
- Cost efficient integration technologies and materials for manufacturing of uncooled infrared bolometer focal plane arrays (FPA) are presented. The technology platform enables 320x240 pixel resolution with a pitch down to 20 mu m and very low NETD. A heterogeneous 3D MEMS integration technology called SOIC (Silicon-On-Integrated-Circuit) is used to combine high performance Si/SiGe bolometers with state-of-the-art electronic read-out-integrated-circuits. The SOIC integration process consists of: (a) Separate fabrication of the CMOS wafer and the MEMS wafer. (b) Adhesive wafer bonding. (c) Sacrificial removal of the MEMS handle wafer. (d) Via-hole etching. (e) Via formation and MEMS device definition. (f) Sacrificial etching of the polymer adhesive. We will present an optimized process flow that only contains dry etch processes for the critical process steps. Thus, extremely small, sub-micrometer feature sizes and vias can be implemented for the infrared bolometer arrays. The Si/SiGe thermistor is grown epitaxially, forming a mono-crystalline multi layer structure. The temperature coefficient of resistance (TCR) is primarily controlled by the concentration of Ge present in the strained SiGe layers. TCR values of more than 3%/K can be achieved with a low signal-to-noise ratio due to the mono-crystalline nature of the material. In addition to its excellent electrical properties, the thermistor material is thermally stable up to temperatures above 600 degrees C, thus enabling the novel integration and packaging techniques described in this paper. Vacuum sealing at the wafer level reduces the overall costs compared to encapsulation after die singulation. Wafer bonding is performed using a Cu-Sn based metallic bonding process followed by getter activation at >= 350 degrees C achieving a pressure in the 0.001 mbar range. After assembling, the final metal phases are stable and fully compatible with high-temperature processes. Hermeticity over the product lifetime is accomplished by well-controlled electro-deposition of metal layers, optimized bonding parameters and a suitable bond frame design.
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| 2. |
- Alexandersson, Jenny, et al.
(författare)
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HR-strategier för regional tillväxt och samverkan? En studie av två arbetsmarknadsintermediärer
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Syftet med denna rapport är att bidra till en ökad förståelse för hur två regionala intermediära organisationer, inom HR-området, arbetar med förändrings- och kompetensrelaterade frågor.En interaktiv forskningsansats har tillämpats vilket innebär att planering och genomförande av forskningsarbetet har skett i dialog med berörda praktiker. Det empiriska materialet utgörs främst av 12 intervjuer med personer som arbetar inom de studerade intermediära organisationerna.Resultaten i denna studie visar att det finns många likheter mellan de två studerade intermediära organisationerna. Båda erbjuder ett brett spektra av HR-tjänster, ägs av sina kundföretag och har en samverkande roll mellan kundföretagen. Resultaten visar också att de båda intermediärerna har utvecklat en relativt speciell roll som intermediärer som innebär att de, i vissa avseenden, arbetar både som en extern och en intern HR-resurs till sina kundföretag. Även när det gäller arbetets organisering visar resultaten på flera likheter mellan de studerade intermediära organisationerna. Personalen i båda intermediärorganisationerna arbetar mycket flexibelt och anpassar sitt arbetssätt efter kundernas behov och önskemål. Få standardiserade modeller eller arbetsverktyg används i arbetet och det finns inte något utvecklat system för dokumentation och kunskapsöverföring som används aktivt inom intermediärorganisationerna. Samtidigt tyder resultaten på att ena av de två organisationerna har en något mer fast struktur med tydligt definierade arbetsområden och roller. Det finns också vissa skillnader mellan organisationerna vad gäller hur man önskar att inrikta och organisera sitt arbete i framtiden. Vidare visar resultaten från denna studie att personalen, inom de båda studerade organisationerna, upplever att deras arbete kan bidra till att kundföretagen får nya perspektiv och synsätt. I bästa fall kan även arbetet bidra till att företagen kan arbeta mer strategiskt och att de lär sig hantera olika problematiska situationer på egen hand och får en ökad beredskap att hantera förändring och problem i framtiden. Samtidigt är många uppdrag av mer akut och kortsiktig karaktär vilket innebär att det kan vara svårt att bidra till mer långsiktiga resultat i kundföretagen.
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| 3. |
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| 4. |
- Blomberg, Jeanette, et al.
(författare)
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Inhibition of cellular FLICE-like inhibitory protein abolishes insensitivity to interferon-α in a resistant variant of the human U937 cell line
- 2011
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Ingår i: Apoptosis (London). - : Springer Science and Business Media LLC. - 1360-8185 .- 1573-675X. ; 16:8, s. 783-794
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Tidskriftsartikel (refereegranskat)abstract
- Type I interferons constitute a family of pleiotropic cytokines that have a key role in both adaptive and innate immunity. The interferon signalling pathways mediate transcriptional regulation of hundreds of genes, which result in mRNA degradation, decreased protein synthesis, cell cycle inhibition and induction of apoptosis. To elucidate regulatory networks important for interferon induced cell death, we generated interferon resistant U937 cells by selection in progressively increasing concentrations of interferon-α (IFN-α). The results show that IFN-α activates the death receptor signalling pathway and that IFN resistance was associated with cross-resistance to several death receptor ligands in a manner similar to previously described Fas resistant U937 cell lines. Increased expression of the long splice variant of the cellular FLICE-like inhibitor protein (cFLIP-L) was associated with the resistance to death receptor and IFN-α stimulation. Accordingly, inhibition of cFLIP-L expression with cycloheximide or through cFLIP short harpin RNA interference restored sensitivity to Fas and/or IFN-α. Thus, we now show that selection for interferon resistance can generate cells with increased expression of cFLIP, which protects the cells from both IFN-α and death receptor mediated apoptosis.
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| 5. |
- Blomberg, Jeanette, 1977-, et al.
(författare)
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Reduced FAS transcription in clones of U937 cells that have acquired resistance to Fas-induced apoptosis
- 2009
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Ingår i: The FEBS Journal. - : Wiley. - 1742-464X .- 1742-4658. ; 276:2, s. 497-508
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Tidskriftsartikel (refereegranskat)abstract
- Susceptibility to cell death is a prerequisite for the elimination of tumour cells by cytotoxic immune cells, chemotherapy or irradiation. Activation of the death receptor Fas is critical for the regulation of immune cell homeostasis and efficient killing of tumour cells by apoptosis. To define the molecular changes that occur during selection for insensitivity to Fas-induced apoptosis, a resistant variant of the U937 cell line was established. Individual resistant clones were isolated and characterized. The most frequently observed defect in the resistant cells was reduced Fas expression, which correlated with decreased FAS transcription. Clones with such reduced Fas expression also displayed partial cross-resistance to tumour necrosis factor-alpha stimulation, but the mRNA expression of tumour necrosis factor receptors was not decreased. Reintroduction of Fas conferred susceptibility to Fas but not to tumour necrosis factor-alpha stimulation, suggesting that several alterations could be present in the clones. The reduced Fas expression could not be explained by mutations in the FAS coding sequence or promoter region, or by silencing through methylations. Protein kinase B and extracellular signal-regulated kinase, components of signalling pathways downstream of Ras, were shown to be activated in some of the resistant clones, but none of the three RAS genes was mutated, and experiments using chemical inhibitors could not establish that the activation of these proteins was the cause of Fas resistance as described in other systems. Taken together, the data illustrate that Fas resistance can be caused by reduced Fas expression, which is a result of an unidentified mode of regulation.
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| 6. |
- Bonlokke, Jakob H., et al.
(författare)
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Exposures and Health Effects of Bioaerosols in Seafood Processing Workers - a Position Statement
- 2019
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Ingår i: Journal of Agromedicine. - 1059-924X .- 1545-0813. ; 24:4, s. 441-448
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Tidskriftsartikel (refereegranskat)abstract
- © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. Occupational hazards exist in the processing of seafood both in land-based facilities as well as on board vessels. Recent findings on occupational injury and respiratory health risks among seafood processing workers were presented and discussed at the IFISH5 conference. Particular emphasis was put on the challenges that im/migrant workers encounter, the greater risks onboard factory vessels, especially where processing machinery are retrofitted to older vessels not primarily designed for this purpose, and the difficulties in assessing and preventing bioaerosol exposures and associated respiratory health risks despite recent advances in characterising agents responsible for allergic and non-allergic reactions. Based on appraisal of existing knowledge in the published literature and new findings presented at the conference, recommendations for immediate actions as well as for future research have been proposed. Among these include the importance of improving extraction ventilation systems, optimising machinery performance, enclosure of bioaerosol sources, improved work organization, and making special efforts to identify and support the needs of im/migrant workers to ensure they also benefit from such improvements. There is a need for studies that incorporate longitudinal study designs, have improved exposure and diagnostic methods, and that address seafood processing in countries with high seafood processing activities such as Asia and those that involve im/migrant workers worldwide. The medical and scientific community has an important role to play in prevention but cannot do this in isolation and should cooperate closely with hygienists, engineers, and national and international agencies to obtain better health outcomes for workers in the seafood industry.
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| 7. |
- Castleton, Christopher, 1969-, et al.
(författare)
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Managing the supercell approximation for charged defects in semiconductors : Finite-size scaling, charge correction factors, the band-gap problem, and the ab initio dielectric constant
- 2006
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 73:035215, s. 11-
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Tidskriftsartikel (refereegranskat)abstract
- The errors arising in ab initio density functional theory studies of semiconductor point defects using the supercell approximation are analyzed. It is demonstrated that (a) the leading finite size errors are inverse linear and inverse cubic in the supercell size and (b) finite size scaling over a series of supercells gives reliable isolated charged defect formation energies to around +-0.05 eV. The scaled results are used to test three correction methods. The Makov-Payne method is insufficient, but combined with the scaling parameters yields an ab initio dielectric constant of 11.6+-4.1 for InP. Gamma point corrections for defect level dispersion are completely incorrect, even for shallow levels, but realigning the total potential in real-space between defect and bulk cells actually corrects the electrostatic defect-defect interaction errors as well. Isolated defect energies to +-0.1 eV are then obtained using a 64 atom supercell, though this does not improve for larger cells. Finally, finite size scaling of known dopant levels shows how to treat the band gap problem: in < or = 200 atom supercells with no corrections, continuing to consider levels into the theoretical conductin band (extended gap) comes closest to experiment. However, for larger cells or when supercell approximation errors are removed, a scissors scheme stretching the theoretical band gap onto the experimental one is in fact correct.
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| 8. |
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| 9. |
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| 10. |
- Deneberg, Stefan, et al.
(författare)
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Prognostic DNA methylation patterns in cytogenetically normal acute myeloid leukemia are predefined by stem cell chromatin marks
- 2011
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 118:20, s. 5573-5582
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Tidskriftsartikel (refereegranskat)abstract
- Cytogenetically normal acute myeloid leukemia (CN-AML) comprise between forty and fifty percent of all adult acute myeloid leukemia (AML) cases. In this clinically diverse group molecular aberrations such as FLT3ITD, NPM1 and CEBPA mutations recently have added to the prognostic accuracy. Aberrant DNA methylation is a hallmark of cancer including AML. We investigated in total 118 CN-AML samples in a test and a validation cohort for genome-wide promoter DNA methylation with Illumina Methylation Bead arrays and compared them to normal myeloid precursors and global gene expression. IDH and NPM1 mutations were associated with different methylation patterns (p=0.0004 and 0.04, respectively). Genome-wide methylation levels were elevated in IDH mutated samples (p=0.006). We observed a negative impact of DNA methylation on transcription. Genes targeted by Polycomb group (PcG) proteins and genes associated with bivalent histone marks in stem cells showed increased aberrant methylation in AML (p<0.0001). Furthermore, high methylation levels of PcG target genes were independently associated with better progression free (OR 0.47, p=0.01) and overall survival (OR 0.36, p=0.001). In summary, genome wide methylation patterns show preferential methylation of PcG targets with prognostic impact in CN-AML.
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