1. |
- Cosentino, Giuliana, et al.
(författare)
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Interstellar Plunging Waves: ALMA Resolves the Physical Structure of Nonstationary MHD Shocks
- 2019
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Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 881:2
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Tidskriftsartikel (refereegranskat)abstract
- Magnetohydrodynamic (MHD) shocks are violent events that inject large amounts of energy in the interstellar medium dramatically modifying its physical properties and chemical composition. Indirect evidence for the presence of such shocks has been reported from the especial chemistry detected toward a variety of astrophysical shocked environments. However, the internal physical structure of these shocks remains unresolved since their expected spatial scales are too small to be measured with current instrumentation. Here we report the first detection of a fully spatially resolved, MHD shock toward the infrared dark cloud (IRDC) G034.77-00.55. The shock, probed by silicon monoxide (SiO) and observed with the Atacama Large Millimeter/submillimeter Array (ALMA), is associated with the collision between the dense molecular gas of the cloud and a molecular gas flow pushed toward the IRDC by the nearby supernova remnant (SNR) W44. The interaction is occurring on subparsec spatial scales thanks to the enhanced magnetic field of the SNR, making the dissipation region of the MHD shock large enough to be resolved with ALMA. Our observations suggest that molecular flow-flow collisions can be triggered by stellar feedback, inducing shocked molecular gas densities compatible with those required for massive star formation.
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2. |
- Olsson Holmström, Helena, et al.
(författare)
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- 2014
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Ingår i: Proceedings of the Euromicro Conference. - : IEEE. ; , s. 9-16
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Konferensbidrag (refereegranskat)abstract
- In most software development companies the road mapping and requirements prioritization process is a complex process in which product management experiences difficulties in getting timely and accurate customer feedback. The feedback loop from customers is slow and often there is a lack of mechanisms that allow for efficient customer data collection and analysis. As a result, there is the risk that requirements prioritization becomes opinion-based rather than data-driven, and that R&D investments are made without an accurate way of continuously validating whether they correspond to customer needs. We call this phenomenon the 'open loop' problem, referring to the challenges for product management to get accurate and timely feedback from customers. To address this problem, we develop the HYPEX model (Hypothesis Experiment Data-Driven Development) that supports companies in running feature experiments to shorten customer feedback loops. We evaluate the model in three software development companies and observe how feature experiments increase the opportunity for data-driven software development.
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3. |
- Ridderstedt, Margareta, 1942-
(författare)
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Vackert och värdigt : Liturgiska textilier från svenska ateljéer 1880 - 1930
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis deals with the production of liturgical textiles in five Swedish studios between 1880 and 1930. It is based on a survey of what was delivered to and preserved in the buildings of the Church of Sweden, more than 4,000 recorded objects. Ecclesiastical liturgical textile art in Sweden forms part of an uninterrupted tradition from the Middle Ages.A new era in ecclesiastical textiles began in Sweden in five major studios in Stockholm and Göteborg. Earlier production during the 19th century had become increasingly stereotypical and there was little interest in ecclesiastical art and liturgy in the parishes of the Swedish church.My survey of this extensive material has enabled me to make conclusions about when new textiles were produced and where, as well as when important changes took place. The iconography, symbols, figurative motifs and texts used in the textiles reveal trends in the historical development of the church’s liturgy. It is also possible to see when the different liturgical colours began to come back into use. Differences in the designs of the textiles show which artistic figures had a dominant influence on ecclesiastical liturgical textiles at a certain time. Five sections in chapter IV deal with a few larger special commissions. The first were for two newly-built churches in the early 1910s by two eminent architects who also designed the textiles. The third church was provided with new textiles in 1917 in connection with an extensive restoration. The fourth case concerns a private initiative to acquire new textiles for an old church. Finally, the ecumenical archbishop’s robes were produced for the Archbishop Nathan Söderblom and worn at the ecumenical meeting in 1925. The archbishop had a firm opinion about its iconographic programme.The five colours were launched in practice on the west coast of Sweden during the 1880s and 1890s. The textile artist Agnes Branting introduced them at the Stockholm Exhibition in 1897. Supplementary commissions for white and green textiles were made from the parishes, for both frontals and chasubles at the end of the 1920s.A wealth of different motifs and differences began to appear between the iconography of the various studios in the 20th century. By no means all liturgical textiles were provided with texts, but enough to make it possible to describe a new trend.Many women and a few male artists developed their aesthetic expression working with ecclesiastical textiles during the fifty years covered by this thesis. The work of the professional studios was fundamental for the development of many young women into resolute, modern professional practitioners.What was linked to the ecclesiastical, the sacred, found expression and was described in words such as beautiful, true and dignified. The textiles embodied an intention to enhance the aesthetic values of worship and ecclesiastical space, to add variation and solemnity. This involved a deeper and more widespread use of motifs and symbols, of high-quality material and of craftsmanship. This study has contributed new knowledge about the period, its aesthetics and its theology.
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4. |
- Hudeček, Jan, et al.
(författare)
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Application of a risk-management framework for integration of stromal tumor-infiltrating lymphocytes in clinical trials
- 2020
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Ingår i: npj Breast Cancer. - : Springer Science and Business Media LLC. - 2374-4677. ; 6:1
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Forskningsöversikt (refereegranskat)abstract
- Stromal tumor-infiltrating lymphocytes (sTILs) are a potential predictive biomarker for immunotherapy response in metastatic triple-negative breast cancer (TNBC). To incorporate sTILs into clinical trials and diagnostics, reliable assessment is essential. In this review, we propose a new concept, namely the implementation of a risk-management framework that enables the use of sTILs as a stratification factor in clinical trials. We present the design of a biomarker risk-mitigation workflow that can be applied to any biomarker incorporation in clinical trials. We demonstrate the implementation of this concept using sTILs as an integral biomarker in a single-center phase II immunotherapy trial for metastatic TNBC (TONIC trial, NCT02499367), using this workflow to mitigate risks of suboptimal inclusion of sTILs in this specific trial. In this review, we demonstrate that a web-based scoring platform can mitigate potential risk factors when including sTILs in clinical trials, and we argue that this framework can be applied for any future biomarker-driven clinical trial setting.
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7. |
- Benstead, Lindsay, et al.
(författare)
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Using Tablet Computers to Implement Surveys in Challenging Environments
- 2017
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Ingår i: Survey Practice. - 2168-0094. ; 10:2
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Tidskriftsartikel (refereegranskat)abstract
- Computer-assisted personal interviewing (CAPI) has increasingly been used in developing countries, but literature and training on best practices have not kept pace. Drawing on our experiences using CAPI to implement the Local Governance Performance Index (LGPI) in Tunisia and Malawi and an election study in Jordan, this paper makes practical recommendations for mitigating challenges and leveraging CAPI’s benefits to obtain high quality data. CAPI offers several advantages. Tablets facilitate complex skip patterns and randomization of long question batteries and survey experiments, which helps to reduce measurement error. Tablets’ global positioning system (GPS) technology reduces sampling error by locating sampling units and facilitating analysis of neighborhood effects. Immediate data uploading, time-stamps for individual questions, and interview duration capture allowed real time data quality checks and interviewer monitoring. Yet, CAPI entails challenges, including costs of learning new software; questionnaire programming; and piloting to resolve coding bugs; and ethical and logistical considerations, such as electricity and Internet connectivity.
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8. |
- Benstein, Ruben M., et al.
(författare)
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Isolation of nuclei tagged in specific cell types (INTACT) in Arabidopsis
- 2023. - 2
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Ingår i: Flower development. - New york : Humana Press. - 9781071632987 - 9781071632994 ; , s. 313-328
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Bokkapitel (refereegranskat)abstract
- Many functionally distinct plant tissues have relatively low numbers of cells that are embedded within complex tissues. For example, the shoot apical meristem (SAM) consists of a small population of pluripotent stem cells surrounded by developing leaves and/or flowers at the growing tip of the plant. It is technically challenging to collect enough high-quality SAM samples for molecular analyses. Isolation of Nuclei Tagged in specific Cell Types (INTACT) is an easily reproducible method that allows the enrichment of biotin-tagged cell-type-specific nuclei from the total nuclei pool using biotin-streptavidin affinity purification. Here, we provide a detailed INTACT protocol for isolating nuclei from the Arabidopsis SAM. One can also adapt this protocol to isolate nuclei from other tissues and cell types for investigating tissue/cell-type-specific transcriptome and epigenome and their changes during developmental programs at a high spatiotemporal resolution. Furthermore, due to its low cost and simple procedures, INTACT can be conducted in any standard molecular laboratory.
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9. |
- Blumi, Isa, 1969-
(författare)
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Reorientating European Imperialism : How Ottomanism Went Global
- 2016
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Ingår i: Die Welt des Islams. - : Brill. - 0043-2539 .- 1570-0607. ; 56:3-4, s. 290-316
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Tidskriftsartikel (refereegranskat)abstract
- Scholars have long studied Western imperialism through the prism of pre-World War I literature and journalism. Characterizing this literature as Orientalist has become programmatic and predictable. The sometimes rigid analysis of this literature often misses, however, the contested dynamics within. This is especially the case with analyses of Ottoman contributions to the rise of a Western colonialist ethos – orientalism, imperialism, and racism – reflecting the political, structural, and economic changes that directly impacted the world. Essentially, colonial pretensions – servicing the ambitions of European imperialism at the expense of peoples in the ‘Orient’ – were articulated at a time when patriotic Ottomans, among others, were pushing back against colonialism. This article explores the possibility that such a response, usefully framed as Ottomanism, contributed regularly to the way peoples interacted in the larger context of a contentious exchange between rival imperialist projects. What is different here is that some articulations of Ottomanism were proactive rather than reactive. In turn, some of the Orientalism that has become synonymous with studies about the relationship between Europe, the Americas, and the peoples “East of the Urals” may have been a response to these Ottomanist gestures.
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10. |
- Aad, G., et al.
(författare)
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- 2012
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swepub:Mat__t (refereegranskat)
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11. |
- Sundström, Simon, 1985-, et al.
(författare)
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Repetition of words and non-words in typically developing children : The role of prosody
- 2014
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Ingår i: First language. - : Sage Publications. - 0142-7237 .- 1740-2344. ; 34:5, s. 428-449
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Tidskriftsartikel (refereegranskat)abstract
- In this study, segmental and prosodic aspects of word repetition and non-word repetition in typically developing children aged four to six years were investigated. Focus was on developmental differences, and on how tonal word accent and word length affect segment production accuracy. Prosodically controlled words and non-words were repeated by 44 Swedish-speaking children. Repetition accuracy for both words and non-words increased with age, and was higher for words than non-words. Further, tonal word accents I and II provided different conditions for segment repetition in favor of accent II during both word repetition and non-word repetition for older children, but only during word repetition for younger children. This suggests age-dependent differences regarding how prosody is stored and integrated with segments. The findings have theoretical significance regarding the role of prosody in the perception, processing and production of phonological information. There are also clinical implications concerning the interpretation of repetition tasks and the potential use of prosody in speech and language intervention.
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12. |
- Van Nguyen, Song, et al.
(författare)
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Cytotoxic T-lymphocyte antigen-4 (CTLA-4) gene polymorphism (rs3087243) is related to risk and survival in patients with colorectal cancer
- 2021
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Ingår i: In Vivo. - : International Institute of Anticancer Research. - 0258-851X .- 1791-7549. ; 35:2, s. 969-975
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND/AIM: Cytotoxic T-lymphocyte antigen-4 (CTLA-4), transiently expressed on T cells, plays a pivotal role in the negative feedback regulation of T-cell activation and proliferation. The aim of the present study was to examine the influence of CTLA-4 gene polymorphism rs3087243 on CRC susceptibility and long-term survival in Swedish patients with CRC.PATIENTS AND METHODS: Genotypes of 491 patients and 433 healthy controls were determined, using TaqMan single nucleotide polymorphism (SNP) assays based on polymerase chain reaction.RESULTS: Patients carrying allele A were found to be at a higher risk of CRC and this allele was found to be more common in patients with disseminated disease compared to localized disease in the right colon. Kaplan-Meier analysis of cancer-specific survival showed that carriers of allele A had the highest risk of CRC-related death.CONCLUSION: The SNP rs3087243 of the CTLA-4 gene was associated with CRC risk and, therefore, it could be a prognostic marker for Swedish patients with CRC.
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17. |
- Pellaco, Lissy, 1992-, et al.
(författare)
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A Matrix-Inverse-Free Implementation of the MU-MIMO WMMSE Beamforming Algorithm
- 2022
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Ingår i: IEEE Transactions on Signal Processing. - : Institute of Electrical and Electronics Engineers (IEEE). - 1053-587X .- 1941-0476. ; 70, s. 6360-6375
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Tidskriftsartikel (refereegranskat)abstract
- The WMMSE beamforming algorithm is a popular approach to address the NP-hard weighted sum rate (WSR) maximization beamforming problem. Although it efficiently finds a local optimum, it requires matrix inverses, eigendecompositions, and bisection searches, operations that are problematic for real-time implementation. In our previous work, we considered the MU-MISO case with single-antenna receivers and effectively replaced such operations by resorting to a first-order method. Here, we consider the more general and challenging MU-MIMO case with multiple-antenna receivers. Our earlier approach does not generalize to this scenario and cannot be applied to replace all the hard-to-parallelize operations that appear in the MU-MIMO case. Thus, we propose to leverage a reformulation of the auxiliary WMMSE function given by Hu et al. By applying gradient descent and Schulz iterations, we formulate the first variant of the WMMSE algorithm applicable to the MU-MIMO case that is free from matrix inverses and other serial operations and hence amenable to both real-time implementation and deep unfolding. From a theoretical viewpoint, we establish its convergence to a stationary point of the WSR maximization problem. From a practical viewpoint, we show that in a deep-unfolding-based implementation, the matrix-inverse-free WMMSE algorithm attains, within a fixed number of iterations, a WSR comparable to the original WMMSE algorithm truncated to the same number of iterations, yet with significant implementation advantages in terms of parallelizability and real-time execution.
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18. |
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19. |
- Alimadadi, Siavash, 1984-, et al.
(författare)
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A palace fit for the future : Desirability in temporal work
- 2022
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Ingår i: Strategic Organization. - : Sage Publications. - 1476-1270 .- 1741-315X. ; 20:1, s. 20-50
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Tidskriftsartikel (refereegranskat)abstract
- Research on the strategic organization of time often assumes that collective efforts are motivated by andoriented toward achieving desirable, although not necessarily well-defined, future states. In situationssurrounded by uncertainty where work has to proceed urgently to avoid an impending disaster, however,temporal work is guided by engaging with both desirable and undesirable future outcomes. Drawing ona real-time, in-depth study of the inception of the Restoration and Renewal program of the Palace ofWestminster, we investigate how organizational actors develop a strategy for an uncertain and highlycontested future while safeguarding ongoing operations in the present and preserving the heritage of thepast. Anticipation of undesirable future events played a crucial role in mobilizing collective efforts to moveforward. We develop a model of future desirability in temporal work to identify how actors construct, link,and navigate interpretations of desirable and undesirable futures in their attempts to create a viable path ofaction. By conceptualizing temporal work based on the phenomenological quality of the future, we advanceunderstanding of the strategic organization of time in pluralistic contexts characterized by uncertainty and urgency.
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20. |
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21. |
- Ding, Jiangwei, et al.
(författare)
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All Roads Lead to Rome? : Genes Causing Dravet Syndrome and Dravet Syndrome-Like Phenotypes
- 2022
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Ingår i: Frontiers in Neurology. - : Frontiers Media S.A.. - 1664-2295. ; 13
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Forskningsöversikt (refereegranskat)abstract
- Background: Dravet syndrome (DS) is a severe epileptic encephalopathy mainly caused by haploinsufficiency of the gene SCN1A, which encodes the voltage-gated sodium channel NaV1. 1 in the brain. While SCN1A mutations are known to be the primary cause of DS, other genes that may cause DS are poorly understood. Several genes with pathogenic mutations result in DS or DS-like phenotypes, which may require different drug treatment approaches. Therefore, it is urgent for clinicians, especially epilepsy specialists to fully understand these genes involved in DS in addition to SCN1A. Particularly for healthcare providers, a deep understanding of these pathogenic genes is useful in properly selecting and adjusting drugs in a more effective and timely manner.Objective: The purpose of this study was to identify genes other than SCN1A that may also cause DS or DS-like phenotypes. Methods: A comprehensive search of relevant Dravet syndrome and severe myoclonic epilepsy in infancy was performed in PubMed, until December 1, 2021. Two independent authors performed the screening for potentially eligible studies. Disagreements were decided by a third, more professional researcher or by all three. The results reported by each study were narratively summarized.Results: A PubMed search yielded 5,064 items, and other sources search 12 records. A total of 29 studies published between 2009 and 2021 met the inclusion criteria. Regarding the included articles, seven studies on PCDH19, three on SCN2A, two on SCN8A, five on SCN1B, two on GABRA1, three on GABRB3, three on GABRG2, and three on STXBP1 were included. Only one study was recorded for CHD2, CPLX1, HCN1 and KCNA2, respectively. It is worth noting that a few articles reported on more than one epilepsy gene.Conclusion: DS is not only identified in variants of SCN1A, but other genes such as PCDH19, SCN2A, SCN8A, SCN1B, GABRA1, GABRB3, GABRG2, KCNA2, CHD2, CPLX1, HCN1A, STXBP1 can also be involved in DS or DS-like phenotypes. As genetic testing becomes more widely available, more genes associated with DS and DS-like phenotypes may be identified and gene-based diagnosis of subtypes of phenotypes in this spectrum may improve the management of these diseases in the future.
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22. |
- Lahsen, Myanna
(författare)
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Evaluating the computational ("Big Data") turn in studies of media coverage of climate change
- 2022
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Ingår i: Wiley Interdisciplinary Reviews. - : Wiley. - 1757-7780 .- 1757-7799. ; 13:2
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Tidskriftsartikel (refereegranskat)abstract
- Machine-assisted big data (MABD) research is enabling quantitative studies of large-scale social phenomena, including societal responses to climate change. The rise of MABD science is causing both enthusiasm and concerns. Reviewing prominent criticisms of MABD and their relevance for MABD explorations of macro-structural factors shaping media coverage of climate change, this article finds that the quality and contributions of such studies depend on avoiding common pitfalls. The review focuses specifically on MABD studies attempts to identify and make sense of correlations-or lack thereof-between climate vulnerability and climate coverage in different countries. The review draws on insights from a single, nationally focused, context-attentive, and relatively more qualitative "small data" study in the Global South (Brazil) to shed critical light on assumptions, claims, and policy recommendations made based on the computer-assisted macro-studies. The review illustrates why more narrowly focused and qualitative small data studies are complementary and indispensable. Besides providing vital understanding of causal relationships that elude MABD studies, more narrowly focused and context-sensitive qualitative studies can foster understanding of the consequential mediating roles of place-specific meaning-making and political strategizing in how climate and weather phenomena are framed by social actors and mass media in particular places. These are dimensions that escape the Big Data quantitative methods, but that are vital to sound policy advice, as illustrated by the Small Data research from Brazil. This article is categorized under: Social Status of Climate Change Knowledge > Knowledge and Practice
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23. |
- Qazi, S. Junaid S.
(författare)
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Flow of Colloidal Mesophases
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation presents new work and results in the flow of complex fluids and experimental methodologies for their investigation. Plate-like colloidal particles of kaolinite and nickel hydroxide are studied. A study of lamellar fragments and their mixture with the nickel hydroxide particles is also presented. The lamellar fragments are self-assembled structures of surfactant molecules that approximate disks. Particles are seen to align with their large faces parallel to the flow direction under shear and elongational strains. Order parameters have been calculated to quantify the extent of preferential alignment and direction of orientation. The experimental data are supported by comparisons with finite-element fluid mechanics calculations that provide estimates of the flow patterns and the strain rates. Elongational strain rates in the range of 5 − 20 s−1 are required to induce a high degree of alignment with the various sizes of the particles whereas about two to three order of magnitude higher shear strain rates are required. The combination of both elongational and shear strain is an effective means to provide a uniform alignment. Comparison of the Peclet numbers calculated for both the shear and elongational flow are presented and this explains that alignment occurs when the energy per particle of the strain is larger than the thermal energy. Mixtures have shown complex behavior: significant changes in the structure are observed that are not seen to the same extent in samples at rest. X-ray diffraction and small-angle neutron scattering techniques are used to characterize the samples and determine the structure in flowing systems. Laboratory X-ray diffraction can be used to characterize dispersed samples. The combination of dynamic light scattering and X-ray diffraction was used to estimate the thickness of the stabilizing layers of the polymer on the colloidal particles. Scattering of synchrotron radiation and neutrons are powerful complementary techniques to provide information about flow and the potential to apply them to systems that are beyond the scope of simple simulations has been demonstrated.
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24. |
- Gawronska, Barbara
(författare)
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Information Extraction from Texts : Adapting a System for Summarization of News Reports to the Domain of Bioinformatics
- 2005
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Ingår i: Transactions on Advanced Research. - : IPSI BgD. - 1820-4511. ; 1:1, s. 20-28
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Tidskriftsartikel (refereegranskat)abstract
- Natural language serves as important information source in all areas of human activity. The presence of a huge amount of texts on the Internet actualizes the problem of efficient information search; visual scanning of all the textual information is difficult and time-consuming. There is a need for efficient, high-quality systems that extract the relevant information from texts. The paper presents the architecture of an experimental system for automatic text understanding and information extraction, which has originally been developed for the domain of news reports. The possibility of adapting the methodology for the purpose of bioinformatics is discussed, and the similarities and differences between texts in the two different domains are discussed and exemplified.
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25. |
- Ilves, Kalle
(författare)
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Modeling and Design of Modular MultilevelConverters for Grid Applications
- 2012
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Grid-connected high-power converters are found in high-voltage direct current transmission (HVDC), static compensators (STATCOMs), and supplies for electric railways. Such power converters should have a high reliability, high efficiency, good harmonic performance, low cost, and a small footprint. Cascaded converters are promising solutions for high-voltage high-power converters since they allow the combination of excellent harmonic performance and low switching frequencies. A high reliability can also be achieved by including redundant submodules in the chain of cascaded converters.One of the emerging cascaded converter topologies is the modular multilevel converter (M2C). This thesis aims to bring clarity to the dimensioning aspects and limiting factors of M2Cs. The dc-capacitor in each submodule is a driving factor for the size and weight of the converter. It is found that the voltage variations across the submodule capacitors will distort the voltage waveforms and also induce alternating components in the current that is circulating between the phase-legs. It is, however, shown that it is possible to control the alternating voltage by feed-forward control. It is also shown that if the circulating current is controlled, the injection of a second-order harmonic component can extend the operating region of the converter. The reason for this is that when the converter is operating close to the boundary of overmodulation the phase and amplitude of the second-order harmonic is chosen such that the capacitors are charged prior to the time when a high voltage should be inserted by the submodules.The controller that is used must be able to balance the sbmodule capacitor voltages. Typically, an increased switching frequency will enhance the performance of the balancing control scheme. In this thesis it is shown that the capacitor voltages can be balanced with programmed modulation, even if fundamental switching frequency is used. This will, however, increase the voltage ripple across the aforementioned capacitors. In order to quantify the requirements on the dc-capacitors a general analysis is provided in this thesis which is based on the assumption that the capacitor voltages are well balanced. It is found that for active power transfer, with a 50 Hz sinusoidal voltage reference, the capacitors must be rated for a combined energy storage of 21 kJ/MW if the capacitor voltages are allowed to increase by 10% above their nominal values.
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26. |
- Ilves, Kalle, et al.
(författare)
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On Energy Storage Requirements in Modular Multilevel Converters
- 2014
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Ingår i: IEEE transactions on power electronics. - 0885-8993 .- 1941-0107. ; 29:1, s. 77-88
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Tidskriftsartikel (refereegranskat)abstract
- The modular multilevel converter is a promising topology for high-voltage and high-power applications. By using submodules equipped with dc-capacitors excellent output voltage waveforms can be obtained at low switching frequencies. The rated energy storage of the submodule capacitors is a driving factor of the size, cost, and weight of the submodules. Although the modular multilevel converter has been thoroughly investigated in the literature, a more detailed analysis of the energy-storage requirements will provide an important contribution for dimensioning and analysis of modular multilevel converters. Such an analysis is presented in this paper. The analysis relates the power transfer capability to the stored energy in the converter and the findings are validated by both simulations and experimental results. The required size of the submodule capacitors in a 4.5 MW grid-connected converter is first calculated and the calculated operating range is then compared with simulation results. The experimental results show that if the average capacitor voltage is allowed to increase 10% above the nominal value an energy storage to power transfer ratio of 21 J/kW can be achieved. It is concluded that the presented theory can relate the power transfer capability to the energy storage in the converter and is thus a valuable tool in the design and analysis of modular multilevel converters.
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27. |
- Jones, G, et al.
(författare)
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Associations between MDMA/ecstasy use and physical health in a U.S. population-based survey sample
- 2022
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Ingår i: Journal of psychopharmacology (Oxford, England). - : SAGE Publications. - 1461-7285 .- 0269-8811. ; 36:10, s. 1129-1135
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Tidskriftsartikel (refereegranskat)abstract
- 3,4-Methylenedioxymethamphetamine (MDMA/“ecstasy”) is an empathogen that can give rise to increased pleasure and empathy and may effectively treat post-traumatic stress disorder. Although prior research has demonstrated associations between ecstasy use and favorable mental health outcomes, the associations between ecstasy and physical health have largely been unexplored. Thus, the goal of this study was to examine the associations between ecstasy use and physical health in a population-based survey sample. Method: This study utilized data from the National Survey on Drug Use and Health (2005–2018), a yearly survey that collects information on substance use and health outcomes in a nationally representative sample of U.S. adults. We used multinomial, ordered, and logistic regression models to test the associations between lifetime ecstasy use and various markers of physical health (self-reported body mass index, overall health, past year heart condition and/or cancer, past year heart disease, past year hypertension, and past year diabetes), controlling for a range of potential confounders. Results: Lifetime ecstasy use was associated with significantly lower risk of self-reported overweightness and obesity (adjusted relative risk ratio range: 0.55–0.88) and lower odds of self-reported past year heart condition and/or cancer (adjusted odds ratio (aOR): 0.67), hypertension (aOR: 0.85), and diabetes (aOR: 0.58). Ecstasy use was also associated with significantly higher odds of better self-reported overall health (aOR: 1.18). Conclusion: Ecstasy shares protective associations with various physical health markers. Future longitudinal studies and clinical trials are needed to more rigorously test these associations.
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28. |
- Lohmander, Stefan, et al.
(författare)
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Standardized incidence rates of total hip replacement for primary hip osteoarthritis in the 5 Nordic countries: similarities and differences
- 2006
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Ingår i: Acta Orthop. - : Medical Journals Sweden AB. - 1745-3674 .- 1745-3682. ; 77:5, s. 733-40
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The national hip registers of the Nordic countries provide an opportunity to compare age- and sex-standardized annual incidence of primary total hip replacement (THR) and types of implants used for primary hip osteoarthritis (OA) in Denmark, Finland, Iceland, Norway and Sweden. METHODS: The data on THR were from the national total hip replacement registries, and population data were from the national statistics agencies. Annual incidence density per 100,000 was calculated for each 5-year age group and it was age-standardized using the WHO European standard population. RESULTS: Crude country-specific annual incidence (all ages) for 1996-2000 varied between 73 and 90. WHO age-standardized annual incidence (all ages) varied between 61 (Finland) and 84 (Iceland). For the ages 50-89, comprising 94-98% of all THRs for OA, annual incidence varied between 217 (Finland) and 309 (Iceland). For Norway, the sex incidence ratio (women/men) was 2, and for the other countries it was between 1.1 and 1.3. The use of uncemented and hybrid replacements was considerably higher in Finland and Denmark than in the other countries. INTERPRETATION: We found overall similarity in THR incidence between the 5 Nordic countries, but substantial differences between women and men, and in the use of different types of implant. Population-based, age-standardized and disease-specific information on THR incidence is required in order to properly explore the causes of differences in provision and practice of THR in different countries, regions and groups, and it will aid in projecting future needs.
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29. |
- Pålsson, Birger, et al.
(författare)
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Partial splenic embolization as pretreatment for antiviral therapy in hepatitis C virus infection
- 2005
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Ingår i: European Journal of Gastroenterology and Hepathology. - 1473-5687. ; 17:11, s. 1153-1155
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Tidskriftsartikel (refereegranskat)abstract
- Antiviral therapy in hepatitis C virus (HCV) infection is limited by haematological side-effects, especially thrombocytopenia and leucopenia. The pancytopenia associated with liver cirrhosis has multifactorial causes, but hypersplenism seems to be a major contributor, especially regarding thrombocytopenia. The use of PSE as a 'Pretreatment' in order to make more patients with HCV-induced cirrhosis and pancytopenia suitable for antiviral therapy using ribavirin and pegylated interferon is a new, promising concept. The setting needs further investigation in prospective, longitudinal studies, in order to evaluate safety, define patient selection criteria, the timing between the PSE procedure and the antiviral therapy and to evaluate the long-term results. The setting needs further investigation in prospective, longitudinal studies, in order to evaluate safety, define patient selection criteria, the timing between the PSE procedure and the antiviral therapy and to evaluate the long-term results.
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- Yoshihara, M, et al.
(författare)
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The Continued Absence of Functional Germline Stem Cells in Adult Ovaries
- 2023
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Ingår i: Stem cells (Dayton, Ohio). - : Oxford University Press (OUP). - 1549-4918 .- 1066-5099. ; 41:2, s. 105-110
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Tidskriftsartikel (refereegranskat)abstract
- Ovaries are central to development, fertility, and reproduction of women. A particularly interesting feature of ovaries is their accelerated aging compared to other tissues, leading to loss of function far before other organs senesce. The limited pool of ovarian follicles is generated before birth and once exhausted, menopause will inevitably commence around the age of 50 years marking the end of fertility. Yet, there are reports suggesting the presence of germline stem cells and neo-oogenesis in adult human ovaries. These observations have fueled a long debate, created experimental fertility treatments, and opened business opportunities. Our recent analysis of cell types in the ovarian cortex of women of fertile age could not find evidence of germline stem cells. Like before, our work has been met with critique suggesting methodological shortcomings. We agree that excellence starts with methods and welcome discussion on the pros and cons of different protocols. In this commentary, we discuss the recent re-interpretation of our work.
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