Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Kristensen Anders) "

Sökning: WFRF:(Kristensen Anders)

Sortera/gruppera träfflistan
  • Kristensen, Fredrik, et al. (författare)
  • A Flexible FFT Processor
  • 2002
  • Ingår i: Norchip Conference, 2002,Copenhagen, Denmark,2002-11-11 - 2002-11-12.
  • Konferensbidrag (refereegranskat)abstract
    • In this paper a flexible FFT processor for OFDM systems is presented. In future wireless systems using OFDM each terminal should be able to handle a wide range of different applications, from pure voice communication to high-speed data transfers, with as little overhead in power consumption and protocol procedure as possible. As the terminals will be battery powered and should be cheap to manufacture an ASIC solution is required. To be able to adapt to different communication schemes and various communication channels the FFT processor must be configurable. To minimize power consumption no more precision than necessary should be used. A pipelined radix22 FFT processor, with the possibility of run time switching between 32-1024 points, have been designed in a standard CMOS 0.35 µm technology. Clock gating and low power memories have been used to reduce power consumption.
  • Kristensen, Fredrik, et al. (författare)
  • A Generic Transmitter for Wireless OFDM Systems
  • 2003
  • Ingår i: Personal, Indoor and Mobile Radio Communications, PIMRC,Beijing, China,2003-09-07 - 2003-09-10.
  • Konferensbidrag (refereegranskat)
  • Kristensen, Fredrik, et al. (författare)
  • Bidirectional FFT Processor for OFDM
  • 2004
  • Ingår i: Swedish System-on-Chip Conference 2004 (SSoCC’04),2004-04-13 - 2004-04-14.
  • Konferensbidrag (övrigt vetenskapligt)
  • Kristensen, Fredrik, et al. (författare)
  • Flexible baseband transmitter for OFDM
  • 2003
  • Ingår i: IASTED International Conference on Circuits, Signals and Systems, 2003,Cancun, Mexico,2003-05-19 - 2003-05-21. - International Assoc. of Science and Technology for Development.
  • Konferensbidrag (refereegranskat)abstract
    • To fully utilize the available spectrum for a wireless communication system it is feasible to adapt to different situations on the channel. In this paper a flexible OFDM transmitter is presented together with basic theory behind OFDM transmission. It is shown that high flexibility can be obtained with a reasonable amount of additional hardware. Part of the design, the FFT-processor, has already been fabricated and measurement results are presented.
  • Kristensen, Fredrik, et al. (författare)
  • Reduced transceiver-delay for OFDM systems
  • 2004
  • Ingår i: IEEE Vehicular Technology Conference, VTC Spring, 2004 ,Milan, Italy,2004-05-17 - 2004-05-19. - IEEE - Institute of Electrical and Electronics Engineers Inc..
  • Konferensbidrag (refereegranskat)abstract
    • In this paper, it is shown that more than half of the data flow buffer, due to a bit reversed FFT output and cyclic prefix in an OFDM transceiver, can be removed. To achieve this, a new pipelined FFT processor is proposed and a cyclic suffix is used instead of the more commonly used cyclic prefix. The FFT processor is used either with a forward or backward data flow, i.e. performing either a decimation in time or a decimation in frequency FFT. However, this approach precludes wordlength optimization in the processor and therefore a semi floating-point arithmetic is used to achieve high signal-to-noise ratio. Total delay through the transceiver is reduced by 25% and for larger transceivers silicon area is reduced by as much as 25%. In addition, the proposed scheme reduces the required amount of memory accesses to insert a cyclic extension, and has the basic properties of a simple interleaver
  • Kristensen, Karl, et al. (författare)
  • Cystatin C, beta-2-microglobulin and beta-trace protein in pre-eclampsia
  • 2007
  • Ingår i: Acta Obstetricia et Gynecologica Scandinavica. - Wiley-Blackwell. - 1600-0412. ; 86:8, s. 921-926
  • Tidskriftsartikel (refereegranskat)abstract
    • Background. An altered renal function is an essential component of the patho-physiology of pre-eclampsia. The plasma levels of low molecular mass proteins, e. g. beta-trace protein, beta-2-microglobulin and cystatin C, are increased in the third trimester of normal pregnancy. The plasma levels of cystatin C and beta-2-microglobulin are further increased in preeclampsia, and the cystatin C level has been reported to be a reliable marker for the disease. The aim of this investigation was to study the plasma levels of beta-trace protein, beta-2-microglobulin and cystatin C in pre-eclampsia, and to determine the diagnostic performance of these proteins compared to that of urate and creatinine. Methods. A case-control study of 57 women diagnosed with pre-eclampsia, and 218 healthy women with uncomplicated singleton pregnancies in the third trimester. Women in the catchment area of Lund, Sweden, were included during an 18-month period from October 2003 to April 2005. Venous blood samples were drawn upon inclusion when diagnosis was made. The maternal plasma concentrations of the 3 proteins were analysed by automated particle-enhanced immunoturbidimetric assays. Results. The plasma levels of the 3 proteins were significantly higher in the third trimester of pre-eclamptic patients compared to healthy pregnant women in the third trimester. The upper reference limits ( parametric 97.5 percentile) were 2.57 mg/l for beta-2-microglobulin, 0.72 mg/l for beta-trace protein and 1.37 mg/l for cystatin C. ROC analysis showed similar diagnostic performance for the 3 proteins, with b-trace protein displaying the best diagnostic performance of all the analytes. Conclusions. In this study, the maternal plasma levels of beta 2-microglobulin, beta-trace protein and cystatin C were all significantly elevated in pre-eclampsia compared to those of healthy pregnant women, and displayed similar diagnostic performance for diagnosing pre-eclampsia. The results indicate that low molecular mass proteins are useful as markers of renal impairment in pre-eclampsia.
  • Kristensen, Karl, et al. (författare)
  • Increased plasma levels of ss(2)-microglobulin, cystatin C and ss-trace protein in term pregnancy are not due to utero-placental production.
  • 2008
  • Ingår i: Scandinavian Journal of Clinical & Laboratory Investigation. - Informa Healthcare. - 1502-7686. ; 68, s. 649-653
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective . To study concentration gradients of the low molecular mass proteins, ss(2)-microglobulin, cystatin C and ss-trace protein, between the uterine and ante-cubital veins, the umbilical artery and vein and in the amniotic fluid compartment. Material and methods. The study comprised 27 healthy women with uncomplicated pregnancies undergoing caesarean section at term. Samples were collected simultaneously and paired t-tests were used to compare mean plasma concentrations. Results . There was no significant concentration gradient in the plasma levels of ss(2)-microglobulin, cystatin C or ss-trace protein between the uterine and antecubital veins. There were no correlations between the protein levels in the compartments. Conclusion . The utero-placental unit does not contribute significantly to the maternal levels of ss(2)-microglobulin, cystatin C and ss-trace protein in normal pregnancy, and the proteins are not likely to be transferred across the placental barrier.
  • Kristensen, Karl, et al. (författare)
  • Serum Amyloid A Protein and C-Reactive Protein in Normal Pregnancy and Preeclampsia.
  • 2009
  • Ingår i: Gynecologic and Obstetric Investigation. - Karger. - 1423-002X. ; 67:4, s. 275-280
  • Tidskriftsartikel (refereegranskat)abstract
    • Aims: To study plasma levels of serum amyloid A protein and C-reactive protein in pregnant women with and without preeclampsia and non-pregnant women. Plasma levels of haptoglobin, orosomucoid and ceruloplasmin were also analyzed. Methods: The study included 295 women with uncomplicated pregnancies, 57 women diagnosed with preeclampsia, and 58 healthy non-pregnant women. Plasma concentrations of acute phase proteins were analyzed by particle-enhanced immunoassays. Non-parametric Kruskal-Wallis and Mann-Whitney U tests were used to test differences between the groups. Results: Plasma levels of C-reactive protein and ceruloplasmin were increased in pregnant women with and without preeclampsia compared to non-pregnant women. Plasma levels of serum amyloid A protein and C-reactive protein were not elevated in women with preeclampsia compared to women with normal pregnancy. Conclusion: The description of preeclampsia as a systemic inflammatory state was not reflected in the plasma levels of serum amyloid A protein and C-reactive protein.
  • Kristensen, Karl, et al. (författare)
  • Temporal changes of the plasma levels of cystatin C, beta-trace protein, beta(2)-microglobulin, urate and creatinine during pregnancy indicate continuous alterations in the renal filtration process
  • 2007
  • Ingår i: Scandinavian Journal of Clinical & Laboratory Investigation. - Informa Healthcare. - 1502-7686. ; 67:6, s. 612-618
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective. To determine the plasma levels of the renal functional markers creatinine, urate, cystatin C, beta(2)-microglobulin and beta-trace protein in samples from the first, second, early third and late third trimesters of 398 healthy women with uncomplicated singleton pregnancies. Material and methods. Plasma samples from 58 healthy non-pregnant women served as controls. The creatinine levels were significantly lower at all time-points in pregnancy, whereas the urate levels were lower during the first and second trimesters but increased in the late third trimester. The cystatin C, beta(2)-microglobulin and beta-trace protein levels displayed similar changes with increased levels in the third trimester but unaltered levels during the first and second trimesters. Results. The results indicate an increased filtration of low-molecular weight molecules during pregnancy, particularly during the first and second trimesters, whereas filtration of 10-30 kDa molecules is decreased in the third but unaltered in the first and second trimesters. The levels of albumin and alpha(2)-macroglobulin were measured in the same samples. Conclusions. The albumin levels decreased in the second and third trimesters, whereas the levels of alpha(2)-macroglobulin were unchanged, which is compatible with a virtually unaltered transfer of alpha(2)-macroglobulin between the intra-and extravascular space during pregnancy and a significantly increased extravascular fraction of albumin.
  • Kristensen, Lars Erik, et al. (författare)
  • Efficacy and tolerability of anti-TNF therapy in psoriatic arthritis patients: Results from the South Swedish Arthritis Treatment Group Register.
  • 2008
  • Ingår i: Annals of the Rheumatic Diseases. - British Medical Association. - 1468-2060. ; 67, s. 364-369
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The use of tumour necrosis factor (TNF) blocking agents in psoriatic arthritis (PsA) is increasing, and the SSATG register has followed patients with PsA for more than 5 years. The aim of the present work therefore was to present efficacy and tolerability data of TNF-blocking agents on PsA in clinical practice, and to study potential predictors for drug survival (the length of time a patient continues to take a particular drug). Materials and methods: Patients (n = 261) with active PsA, starting anti-TNF therapy for the first time in southern Sweden, were included. Basal characteristics, disease activity measures, and termination reason for blockers were prospectively collected during the period April 1999 to September 2006. Cox proportional hazard models were used to investigate predictors for treatment termination. Results: Overall, response rates at 3–12 months for global visual analogue scale (VASglobal50) and pain VAS (VASpain50) were about 50%, whereas response rates for European League Against Rheumatism (EULAR) scoring "overall" and EULAR "good" were around 75% and 55%, respectively. Concomitant methotrexate (MTX) (hazard ratio (HR) 0.64, 95% CI 0.39–0.95, p = 0.03), etanercept (HR 0.49, 95% CI 0.28–0.86, p = 0.01), and high C-reactive protein (CRP) levels (HR 0.77, 95% CI 0.61–0.97, p = 0.03) at treatment initiation were associated with better overall drug survival. The improved drug survival of concomitant MTX appeared to be related to significantly fewer dropouts because of adverse events (HR = 0.24 (0.11–0.52), p<0.01). The blockers were well tolerated with a rate of serious adverse events of 5–6% per year. No unexpected serious adverse events were observed. Conclusion: Concomitant MTX and high CRP levels are associated with treatment continuation of anti-TNF therapy in patients with PsA regardless of joint distribution. The positive effect of MTX was primarily linked to fewer dropouts because of adverse events.
Skapa referenser, mejla, bekava och länka
fritt online (27)
Typ av publikation
tidskriftsartikel (91)
konferensbidrag (20)
forskningsöversikt (5)
bokkapitel (3)
rapport (1)
annan publikation (1)
visa fler...
doktorsavhandling (1)
visa färre...
Typ av innehåll
refereegranskat (113)
övrigt vetenskapligt (25)
Gülfe, Anders, (12)
Tegenfeldt, Jonas, (11)
Geborek, Pierre, (9)
Saxne, Tore, (8)
Olsson, Anders, (7)
Nevanlinna, Heli (6)
visa fler...
Blomqvist, Carl (6)
Chang-Claude, Jenny (6)
Wang, Qin (6)
Haiman, Christopher ... (6)
Giles, Graham G (6)
Brenner, Hermann (6)
Neuhausen, Susan L (6)
Nilsson, Peter, (6)
Darabi, Hatef (6)
Brunet, Joan, (6)
Buys, Saundra S. (6)
Devilee, Peter (6)
Hopper, John L. (6)
Milne, Roger L. (6)
Benitez, Javier (6)
Burwinkel, Barbara (6)
Brauch, Hiltrud (6)
Hamann, Ute (6)
Lindblom, Annika (6)
Margolin, Sara (6)
Kosma, Veli-Matti (6)
Olson, Janet E. (6)
Czene, Kamila (6)
Cox, Angela (6)
Anton-Culver, Hoda (6)
Andrulis, Irene L. (6)
Knight, Julia A. (6)
Dunning, Alison M. (6)
Guenel, Pascal (6)
Liljas, Anders, (6)
Bolla, Manjeet K. (6)
Bojesen, Stig E. (6)
Figueroa, Jonine (6)
Zheng, Wei (6)
Shu, Xiao-Ou (6)
Ehrencrona, Hans, (6)
McGuffog, Lesley (6)
Barrowdale, Daniel (6)
Frost, Debra (6)
Mazoyer, Sylvie (6)
Lubinski, Jan (6)
Jakubowska, Anna (6)
Gronwald, Jacek (6)
Domchek, Susan M. (6)
visa färre...
Lunds universitet (73)
Uppsala universitet (17)
Göteborgs universitet (10)
Linköpings universitet (9)
Karolinska Institutet (9)
Umeå universitet (8)
visa fler...
Chalmers tekniska högskola (6)
Kungliga Tekniska Högskolan (3)
Stockholms universitet (3)
Örebro universitet (1)
Karlstads universitet (1)
visa färre...
Engelska (121)
Forskningsämne (UKÄ/SCB)
Medicin och hälsovetenskap (67)
Naturvetenskap (32)
Teknik (13)
Lantbruksvetenskap (3)
Samhällsvetenskap (3)
Humaniora (2)


pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy