| 1. |
- Abadie, J., et al.
(författare)
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Implementation and testing of the first prompt search for gravitational wave transients with electromagnetic counterparts
- 2012
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Ingår i: Astronomy & Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 539
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Tidskriftsartikel (refereegranskat)abstract
- Aims. A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods. During two observing periods (Dec. 17, 2009 to Jan. 8, 2010 and Sep. 2 to Oct. 20, 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability to reconstruct source positions correctly. Results. For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with similar to 50% or better probability with a few pointings of wide-field telescopes.
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| 2. |
- Abadie, J., et al.
(författare)
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Search for gravitational waves from low mass compact binary coalescence in LIGO's sixth science run and Virgo's science runs 2 and 3
- 2012
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Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 85:8
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Tidskriftsartikel (refereegranskat)abstract
- We report on a search for gravitational waves from coalescing compact binaries using LIGO and Virgo observations between July 7, 2009, and October 20, 2010. We searched for signals from binaries with total mass between 2 and 25M(circle dot); this includes binary neutron stars, binary black holes, and binaries consisting of a black hole and neutron star. The detectors were sensitive to systems up to 40 Mpc distant for binary neutron stars, and further for higher mass systems. No gravitational-wave signals were detected. We report upper limits on the rate of compact binary coalescence as a function of total mass, including the results from previous LIGO and Virgo observations. The cumulative 90% confidence rate upper limits of the binary coalescence of binary neutron star, neutron star-black hole, and binary black hole systems are 1.3 x 10(-4), 3.1 x 10(-5), and 6.4 x 10(-6) Mpc(-3) yr(-1), respectively. These upper limits are up to a factor 1.4 lower than previously derived limits. We also report on results from a blind injection challenge.
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| 3. |
- Abadie, J., et al.
(författare)
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All-sky search for periodic gravitational waves in the full S5 LIGO data
- 2012
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Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 85:2
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Tidskriftsartikel (refereegranskat)abstract
- We report on an all-sky search for periodic gravitational waves in the frequency band 50-800 Hz and with the frequency time derivative in the range of 0 through -6 x 10(-9) Hz/s. Such a signal could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. After recent improvements in the search program that yielded a 10x increase in computational efficiency, we have searched in two years of data collected during LIGO's fifth science run and have obtained the most sensitive all-sky upper limits on gravitational-wave strain to date. Near 150 Hz our upper limit on worst-case linearly polarized strain amplitude h(0) is 1 x 10(-24), while at the high end of our frequency range we achieve a worst-case upper limit of 3.8 x 10(-24) for all polarizations and sky locations. These results constitute a factor of 2 improvement upon previously published data. A new detection pipeline utilizing a loosely coherent algorithm was able to follow up weaker outliers, increasing the volume of space where signals can be detected by a factor of 10, but has not revealed any gravitational-wave signals. The pipeline has been tested for robustness with respect to deviations from the model of an isolated neutron star, such as caused by a low-mass or long-period binary companion.
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| 6. |
- Bruggmann, P., et al.
(författare)
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Historical epidemiology of hepatitis C virus (HCV) in selected countries
- 2014
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Ingår i: Journal of Viral Hepatitis. - Hoboken : Wiley-Blackwell. - 1352-0504 .- 1365-2893. ; 21, s. 5-33
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Tidskriftsartikel (refereegranskat)abstract
- Chronic infection with hepatitis C virus (HCV) is a leading indicator for liver disease. New treatment options are becoming available, and there is a need to characterize the epidemiology and disease burden of HCV. Data for prevalence, viremia, genotype, diagnosis and treatment were obtained through literature searches and expert consensus for 16 countries. For some countries, data from centralized registries were used to estimate diagnosis and treatment rates. Data for the number of liver transplants and the proportion attributable to HCV were obtained from centralized databases. Viremic prevalence estimates varied widely between countries, ranging from 0.3% in Austria, England and Germany to 8.5% in Egypt. The largest viremic populations were in Egypt, with 6358000 cases in 2008 and Brazil with 2106000 cases in 2007. The age distribution of cases differed between countries. In most countries, prevalence rates were higher among males, reflecting higher rates of injection drug use. Diagnosis, treatment and transplant levels also differed considerably between countries. Reliable estimates characterizing HCV-infected populations are critical for addressing HCV-related morbidity and mortality. There is a need to quantify the burden of chronic HCV infection at the national level.
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| 7. |
- Razavi, H., et al.
(författare)
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The present and future disease burden of hepatitis C virus (HCV) infection with today's treatment paradigm
- 2014
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Ingår i: Journal of Viral Hepatitis. - Hoboken : Wiley-Blackwell. - 1352-0504 .- 1365-2893. ; 21:Suppl. 1, s. 34-59
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Tidskriftsartikel (refereegranskat)abstract
- The disease burden of hepatitis C virus (HCV) is expected to increase as the infected population ages. A modelling approach was used to estimate the total number of viremic infections, diagnosed, treated and new infections in 2013. In addition, the model was used to estimate the change in the total number of HCV infections, the disease progression and mortality in 2013-2030. Finally, expert panel consensus was used to capture current treatment practices in each country. Using today's treatment paradigm, the total number of HCV infections is projected to decline or remain flat in all countries studied. However, in the same time period, the number of individuals with late-stage liver disease is projected to increase. This study concluded that the current treatment rate and efficacy are not sufficient to manage the disease burden of HCV. Thus, alternative strategies are required to keep the number of HCV individuals with advanced liver disease and liver-related deaths from increasing.
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| 8. |
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| 9. |
- Wedemeyer, H., et al.
(författare)
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Strategies to manage hepatitis C virus (HCV) disease burden
- 2014
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Ingår i: Journal of Viral Hepatitis. - Hoboken : Wiley-Blackwell. - 1352-0504 .- 1365-2893. ; 21, s. 60-89
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Tidskriftsartikel (refereegranskat)abstract
- The number of hepatitis C virus (HCV) infections is projected to decline while those with advanced liver disease will increase. A modeling approach was used to forecast two treatment scenarios: (i) the impact of increased treatment efficacy while keeping the number of treated patients constant and (ii) increasing efficacy and treatment rate. This analysis suggests that successful diagnosis and treatment of a small proportion of patients can contribute significantly to the reduction of disease burden in the countries studied. The largest reduction in HCV-related morbidity and mortality occurs when increased treatment is combined with higher efficacy therapies, generally in combination with increased diagnosis. With a treatment rate of approximately 10%, this analysis suggests it is possible to achieve elimination of HCV (defined as a >90% decline in total infections by 2030). However, for most countries presented, this will require a 3-5 fold increase in diagnosis and/or treatment. Thus, building the public health and clinical provider capacity for improved diagnosis and treatment will be critical.
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| 10. |
- Chumak, A. V., et al.
(författare)
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Advances in Magnetics Roadmap on Spin-Wave Computing
- 2022
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Ingår i: IEEE Transactions on Magnetics. - 0018-9464. ; 58:6
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Tidskriftsartikel (refereegranskat)abstract
- Magnonics addresses the physical properties of spin waves and utilizes them for data processing. Scalability down to atomic dimensions, operation in the GHz-to-THz frequency range, utilization of nonlinear and nonreciprocal phenomena, and compatibility with CMOS are just a few of many advantages offered by magnons. Although magnonics is still primarily positioned in the academic domain, the scientific and technological challenges of the field are being extensively investigated, and many proof-of-concept prototypes have already been realized in laboratories. This roadmap is a product of the collective work of many authors that covers versatile spin-wave computing approaches, conceptual building blocks, and underlying physical phenomena. In particular, the roadmap discusses the computation operations with Boolean digital data, unconventional approaches like neuromorphic computing, and the progress towards magnon-based quantum computing. The article is organized as a collection of sub-sections grouped into seven large thematic sections. Each sub-section is prepared by one or a group of authors and concludes with a brief description of current challenges and the outlook of further development for each research direction. Author
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| 11. |
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| 13. |
- Kloss, M., et al.
(författare)
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Recurrent versus first cervical artery dissection - a retrospective study of clinical and vascular characteristics
- 2020
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Ingår i: European Journal of Neurology. - : Wiley. - 1351-5101 .- 1468-1331. ; 27:11, s. 2185-2190
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Tidskriftsartikel (refereegranskat)abstract
- Background and purpose Most recurrent cervical artery dissection (CeAD) events occur shortly after the acute first CeAD. This study compared the characteristics of recurrent and first CeAD events and searched for associations between subsequent events of an individual person. Methods Cervical artery dissection patients with a new CeAD event occurring during a 3-6 month follow-up were retrospectively selected in seven specialized stroke centers. Clinical and vascular characteristics of the initial and the recurrent CeADs were compared. Results The study sample included 76 patients. Recurrent CeADs were occlusive in one (1.3%) patient, caused cerebral ischaemia in 13 (17.1%) and were asymptomatic in 39 (51.3%) patients, compared to 29 (38.2%) occlusive, 42 (55.3%) ischaemic and no asymptomatic first CeAD events. In 52 (68.4%) patients, recurrent dissections affected both internal carotid arteries or both vertebral arteries, whilst 24 (31.6%) patients had subsequent dissections in both types of artery. Twelve (28.6%) of 42 patients with an ischaemic first dissection had ischaemic symptoms due to the recurrent CeADs, too. However, only one (1.3%) of 34 patients with a non-ischaemic first CeAD suffered ischaemia upon recurrence. Conclusion Recurrent CeAD typically affects the same site of artery. It causes ischaemic events less often than the first CeAD. The risk that patients who presented with solely non-ischaemic symptoms of a first CeAD will have ischaemic symptoms in the case of a recurrent CeAD seems very small.
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| 14. |
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| 15. |
- Hayes, MG, et al.
(författare)
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Genome-wide association of polycystic ovary syndrome implicates alterations in gonadotropin secretion in European ancestry populations
- 2015
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 6, s. 7502-
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Tidskriftsartikel (refereegranskat)abstract
- Polycystic ovary syndrome (PCOS) is a common, highly heritable complex disorder of unknown aetiology characterized by hyperandrogenism, chronic anovulation and defects in glucose homeostasis. Increased luteinizing hormone relative to follicle-stimulating hormone secretion, insulin resistance and developmental exposure to androgens are hypothesized to play a causal role in PCOS. Here we map common genetic susceptibility loci in European ancestry women for the National Institutes of Health PCOS phenotype, which confers the highest risk for metabolic morbidities, as well as reproductive hormone levels. Three loci reach genome-wide significance in the case–control meta-analysis, two novel loci mapping to chr 8p23.1 and chr 11p14.1, and a chr 9q22.32 locus previously found in Chinese PCOS. The same chr 11p14.1 SNP, rs11031006, in the region of the follicle-stimulating hormone B polypeptide (FSHB) gene strongly associates with PCOS diagnosis and luteinizing hormone levels. These findings implicate neuroendocrine changes in disease pathogenesis.
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| 16. |
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| 17. |
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| 18. |
- Evers, Arne, et al.
(författare)
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Testing Practices and Attitudes Toward Tests and Testing : An International Survey
- 2017
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Ingår i: International Journal of Testing. - : ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD. - 1530-5058 .- 1532-7574. ; 17:2, s. 158-190
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Tidskriftsartikel (refereegranskat)abstract
- On behalf of the International Test Commission and the European Federation of Psychologists' Associations a world-wide survey on the opinions of professional psychologists on testing practices was carried out. The main objective of this study was to collect data for a better understanding of the state of psychological testing worldwide. These data could guide the actions and measures taken by ITC, EFPA, and other stakeholders. A questionnaire was administered to 20,467 professional psychologists from 29 countries. Five scales were constructed relating to: concern over incorrect test use, regulations on tests and testing, internet and computerized testing, appreciation of tests, and knowledge and training relating to test use. Equivalence across countries was evaluated using the alignment method, four scales demonstrated acceptable levels of invariance. Multilevel analysis was used to determine how scores were related to age, gender, and specialization, as well as how scores varied between countries. Although the results show a high appreciation of tests in general, the appreciation of internet and computerized testing is much lower. These scales show low variability over countries, whereas differences between countries on the other reported scales are much greater. This implies the need for some overarching improvements as well as country-specific actions.
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| 19. |
- Lee, Byung-Boong, et al.
(författare)
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Venous hemodynamic changes in lower limb venous disease : the UIP consensus according to scientific evidence
- 2016
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Ingår i: International Journal of Angiology. - : Springer. - 0392-9590 .- 1827-1839. ; 35:3, s. 236-352
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Tidskriftsartikel (refereegranskat)abstract
- There are excellent guidelines for clinicians to manage venous diseases but few reviews to assess their hemodynamic background. Hemodynamic concepts that evolved in the past have largely remained unchallenged in recent decades, perhaps due to their often complicated nature and in part due to emergence of new diagnostic techniques. Duplex ultrasound scanning and other imaging techniques which evolved in the latter part of the 20th century have dominated investigation. They have greatly improved our understanding of the anatomical patterns of venous reflux and obstruction. However, they do not provide the physiological basis for understanding the hemodynamics of flow, pressure, compliance and resistance. Hemodynamic investigations appear to provide a better correlation with post-treatment clinical outcome and quality of life than ultrasound findings. There is a far better prospect for understanding the complete picture of the patient's disability and response to management by combining ultrasound with hemodynamic studies. Accordingly, at the instigation of Dr Angelo Scuderi, the Union Internationale de Phlebologie (UIP) executive board commissioned a large number of experts to assess all aspects of management for venous disease by evidence-based principles. These included experts from various member societies including the European Venous Forum (EVF), American Venous Forum (AVF), American College of Phlebology (ACP) and Cardiovascular Disease Educational and Research Trust (CDERT). Their aim was to confirm or dispel long-held hemodynamic principles and to provide a comprehensive review of venous hemodynamic concepts underlying the pathophysiology of lower limb venous disorders, their usefulness for investigating patients and the relevant hemodynamic changes associated with various forms of treatment. Chapter 1 is devoted to basic hemodynamic concepts and normal venous physiology. Chapter 2 presents the mechanism and magnitude of hemodynamic changes in acute deep vein thrombosis indicating their pathophysiological and clinical significance. Chapter 3 describes the hemodynamic changes that occur in different classes of chronic venous disease and their relation to the anatomic extent of disease in the macrocirculation and microcirculation. The next four chapters (Chapters 4-7) describe the hemodynamic changes resulting from treatment by compression using different materials, intermittent compression devices, pharmacological agents and finally surgical or endovenous ablation. Chapter 8 discusses the unique hemodynamic features associated with alternative treatment techniques used by the CHIVA and ASVAL. Chapter 9 describes the hemodynamic effects following treatment to relieve pelvic reflux and obstruction. Finally, Chapter 10 demonstrates that contrary to general belief there is a moderate to good correlation between certain hemodynamic measurements and clinical severity of chronic venous disease. The authors believe that this document will be a timely asset to both clinicians and researchers alike. It is directed towards surgeons and physicians who are anxious to incorporate the conclusions of research into their daily practice. It is also directed to postgraduate trainees, vascular technologists and bioengineers, particularly to help them understand the hemodynamic background to pathophysiology, investigations and treatment of patients with venous disorders. Hopefully it will be a platform for those who would like to embark on new research in the field of venous disease.
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