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We present a new approach to analyse the deformation of the left ventricle of the heart based on a parametric model that gives a compact representation of a set of points in a 3-D image. We present a strategy for tracking surfaces in a sequence of 3-D cardiac images. Following tracking, we then infer quantitative parameters which characterize: left ventricle motion, volume of left ventricle, ejection fraction, amplitude and twist component of cardiac motion. We explain the computation of these parameters using our model. Experimental results are shown in time sequences of two modalities of medical images, nuclear medicine and X-ray computed tomography (CT). Video sequences presenting these results are on the CD-ROM. 相似文献
3.
GS Wengler A Lanfranchi T Frusca R Verardi A Neva D Brugnoni S Giliani M Fiorini P Mella F Guandalini E Mazzolari S Pecorelli LD Notarangelo F Porta AG Ugazio 《Canadian Metallurgical Quarterly》1996,348(9040):1484-1487
BACKGROUND: X-linked severe combined immunodeficiency (SCIDXI) is an inherited immune defect which leads to death in infancy from severe infections. The defect is caused by mutations of the IL-2RG gene that encodes for the common gamma chain shared by several cytokine receptors. The disease is characterised by lack of T and NK cells with normal numbers of B cells. SCIDXI can be cured by bone marrow transplantation (BMT) or prevented by abortion after prenatal diagnosis. METHODS: A male fetus was diagnosed as having SCIDXI by molecular, immunophenotypic, and functional analyses. The fetus was injected intraperitoneally under ultrasound guidance with CD34 haematopoietic progenitor cells purified from paternal bone marrow and T-cell depleted by E rosetting. Chimerism analysis was by HLA-DQ alpha typing and gamma-chain staining on cord blood. FINDINGS: A healthy 3.6 kg boy was delivered by caesarean section at 38 weeks of gestation with no clinical or laboratory signs of graft-versus-host disease. Engraftment of donor-derived CD2 cells was found at birth. At 3.5 months of age the infant is well and his T-cell counts and function are normal. INTERPRETATION: In-utero transplantation of haematopoietic progenitor cells allowed immune reconstitution of a fetus with SCIDXI and may be an alternative to elective abortion. Our report should encourage applications of this method to other inherited disorders curable by BMT. 相似文献
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Urinary amino acid excretion was determined in 31 leukemic patients and 29 normal individuals by rapid gas chromatographic analysis of 16 amino acids as their N-acetyl-n-propyl esters. The leukemic patients were concurrently undergoing, or had recently completed, chemotherapy. It was found that aspartic acid, threonine, and serine were of significance in distinguishing between patients "on" therapy and those "off" therapy. Patients with advanced disease have the greatest aminoaciduria, although both the normal and leukemic populations have wide individual ranges. Within both populations, men excrete a greater variety and quantity of amino acids than women. It is concluded that analysis of urinary amino acids represents a history of complex metabolic events, which is potentially useful for evaluating patient response to chemotherapy in leukemia. 相似文献
6.
Rodrigo Calderón-Rico Roberto Carrasco-Alvarez Javier Vázquez Castillo 《Telecommunication Systems》2018,68(2):193-200
In a cognitive radio system, the goal is to make better use of the radio electric spectrum, allowing non-licensed users access to those currently unused electromagnetic bands assigned to licensed users (LUs). This can be achieved using OFDM, where the non-licensed users must select the temporarily available subcarriers and turn off those subcarriers used by LUs in order to avoid interference. Hence, only a subset of the subcarriers can be used for data or pilot tone transmission. To this end, some pilot allocation algorithms have been proposed for this dynamic scenario, but they are designed in such away that an equispaced pilot placement is respected (as much as possible) while minimizing the mean squared error of the channel estimate. Nevertheless, this equispaced placement can lead to the use of an increased number of pilots in order to achieve a good channel estimation. In this work, a new pilot allocation algorithm based on wavelet transform is presented. The proposed algorithm uses the discrete wavelet transform to analyze the previous channel state information, taking the knowledge of the available subcarriers into account to provide a suboptimal solution for the pilot positions. This solution leads to a non-equispaced pilot placement, which improves the channel estimation and consequently, the system performance. Likewise, the introduced algorithm allows a reduction of the number of necessary pilots, which aids in increasing the data rate. Finally, simulation results corroborate the effectiveness of the algorithm in dynamic channel scenarios. 相似文献
7.
Carlo Galuzzi Chunyang Gou Humberto Calderón Georgi N. Gaydadjiev Stamatis Vassiliadis 《Journal of Signal Processing Systems》2009,57(1):33-44
In this paper we present an efficient data fetch circuitry to retrieve several operands from a n-way parallel memory system in a single machine cycle. The proposed address generation unit operates with an improved version
of the low-order parallel memory access approach. Our design supports data structures of arbitrary lengths and different odd
strides. The experimental results show that our address generation unit is capable of generating eight 32 − bit addresses every 6 ns for different strides when implemented on a VIRTEX-II PRO xc2vp30-7ff1696 FPGA device using only trivial
hardware resources.
Carlo Galuzzi received the M.Sc. in Mathematics (summa cum laude) from Università Degli Studi di Milano, Italy in 2003. He is currently at the final stage of his Ph.D. in Computer Engineering at TU Delft, The Netherlands. He is a reviewer for more than 20 international conferences and journals. He served as publication chair for many conferences, e.g. MICRO-41, SAMOS 2006-08, DTIS 2007. His research interests include instruction-set extension, hardware-software partitioning and graph theory. Carlo received the best paper award at ARC 2008. Chunyang Gou was born in Sichuan, China in 1981. He received the Bachelor degree from University of Electronic Science and Technology of China (UESTC), Chengdu, China in 2003 and the MSc degree from Tsinghua University, Beijing, China in 2006. He is currently working towards the Ph.D. in Computer Engineering in the Delft University of Technology, The Netherlands. His research interests include computer architecture in general, with particular emphasis on high-performance memory hierarchies. Humberto Calderón was born in La Paz, Bolivia, in 1964. He received the M.Sc. degree in Computer Sciences from the ITCR (Costa Rica) in 1997 and the Ph.D. degree in computer engineering from TU Delft, The Netherlands, in 2007. His current research interests include reconfigurable computing, multimedia embedded systems, computer arithmetic, intelligent control and robotics. He currently joined the “Istituto Italiano di Tecnologia in Genova, Italy, as a senior engineer and researcher. Georgi N. Gaydadjiev was born in Plovdiv, Bulgaria, in 1964. He is currently assistant professor at the Computer Engineering Laboratory, Delft University of Technology, The Netherlands. His research and development industrial experience includes more than 15 years in hardware and software design at System Engineering Ltd. in Pravetz Bulgaria and Pijnenburg Microelectronics and Software B.V. in Vught, the Netherlands. His research interests include: embedded systems design, advanced computer architectures, hardware/software co-design, VLSI design, cryptographic systems and computer systems testing. Georgi has been a member of many conference program committees at different levels, e.g. ISC, ICS, Computing Frontiers, ICCD, HiPC and more. He was program chair of SAMOS in 2006 and was a general chair in 2007. Georgi received the best paper awards at Usenix/SAGE LISA 2006 and WiSTP 2007. He is IEEE and ACM member. Stamatis Vassiliadis (M’86-SM’92-F’97) was born in Manolates, Samos, Greece 1951. Regrettably, Prof. Vassiliadis deceased in April 2007. He was a chair professor in the Electrical Engineering department of Delft University of Technology (TU Delft), The Netherlands. He had also served in the EE faculties of Cornell University, Ithaca, NY and the State University of New York (S.U.N.Y.), Binghamton, NY. He worked for a decade with IBM where he had been involved in a number of advanced research and development projects. For his work he received numerous awards including 24 publication awards, 15 invention awards and an outstanding innovation award for engineering/scientific hardware design. His 72 USA patents rank him as the top all time IBM inventor. Dr. Vassiliadis received an honorable mention Best Paper award at the ACM/IEEE MICRO25 in 1992 and Best Paper awards in the IEEE CAS (1998, 2001), IEEE ICCD (2001), PDCS (2002) and the best poster award in the IEEE NANO (2005). He is an IEEE and ACM fellow and a member of the Royal Dutch Academy of Science. 相似文献
Georgi N. GaydadjievEmail: |
Carlo Galuzzi received the M.Sc. in Mathematics (summa cum laude) from Università Degli Studi di Milano, Italy in 2003. He is currently at the final stage of his Ph.D. in Computer Engineering at TU Delft, The Netherlands. He is a reviewer for more than 20 international conferences and journals. He served as publication chair for many conferences, e.g. MICRO-41, SAMOS 2006-08, DTIS 2007. His research interests include instruction-set extension, hardware-software partitioning and graph theory. Carlo received the best paper award at ARC 2008. Chunyang Gou was born in Sichuan, China in 1981. He received the Bachelor degree from University of Electronic Science and Technology of China (UESTC), Chengdu, China in 2003 and the MSc degree from Tsinghua University, Beijing, China in 2006. He is currently working towards the Ph.D. in Computer Engineering in the Delft University of Technology, The Netherlands. His research interests include computer architecture in general, with particular emphasis on high-performance memory hierarchies. Humberto Calderón was born in La Paz, Bolivia, in 1964. He received the M.Sc. degree in Computer Sciences from the ITCR (Costa Rica) in 1997 and the Ph.D. degree in computer engineering from TU Delft, The Netherlands, in 2007. His current research interests include reconfigurable computing, multimedia embedded systems, computer arithmetic, intelligent control and robotics. He currently joined the “Istituto Italiano di Tecnologia in Genova, Italy, as a senior engineer and researcher. Georgi N. Gaydadjiev was born in Plovdiv, Bulgaria, in 1964. He is currently assistant professor at the Computer Engineering Laboratory, Delft University of Technology, The Netherlands. His research and development industrial experience includes more than 15 years in hardware and software design at System Engineering Ltd. in Pravetz Bulgaria and Pijnenburg Microelectronics and Software B.V. in Vught, the Netherlands. His research interests include: embedded systems design, advanced computer architectures, hardware/software co-design, VLSI design, cryptographic systems and computer systems testing. Georgi has been a member of many conference program committees at different levels, e.g. ISC, ICS, Computing Frontiers, ICCD, HiPC and more. He was program chair of SAMOS in 2006 and was a general chair in 2007. Georgi received the best paper awards at Usenix/SAGE LISA 2006 and WiSTP 2007. He is IEEE and ACM member. Stamatis Vassiliadis (M’86-SM’92-F’97) was born in Manolates, Samos, Greece 1951. Regrettably, Prof. Vassiliadis deceased in April 2007. He was a chair professor in the Electrical Engineering department of Delft University of Technology (TU Delft), The Netherlands. He had also served in the EE faculties of Cornell University, Ithaca, NY and the State University of New York (S.U.N.Y.), Binghamton, NY. He worked for a decade with IBM where he had been involved in a number of advanced research and development projects. For his work he received numerous awards including 24 publication awards, 15 invention awards and an outstanding innovation award for engineering/scientific hardware design. His 72 USA patents rank him as the top all time IBM inventor. Dr. Vassiliadis received an honorable mention Best Paper award at the ACM/IEEE MICRO25 in 1992 and Best Paper awards in the IEEE CAS (1998, 2001), IEEE ICCD (2001), PDCS (2002) and the best poster award in the IEEE NANO (2005). He is an IEEE and ACM fellow and a member of the Royal Dutch Academy of Science. 相似文献
8.
Durlam M. Naji P.J. Omair A. DeHerrera M. Calder J. Slaughter J.M. Engel B.N. Rizzo N.D. Grynkewich G. Butcher B. Tracy C. Smith K. Kyler K.W. Ren J.J. Molla J.A. Feil W.A. Williams R.G. Tehrani S. 《Solid-State Circuits, IEEE Journal of》2003,38(5):769-773
A low-power 1-Mb magnetoresistive random access memory (MRAM) based on a one-transistor and one-magnetic tunnel junction (1T1MTJ) bit cell is demonstrated. This is the largest MRAM memory demonstration to date. In this circuit, the magnetic tunnel junction (MTJ) elements are integrated with CMOS using copper interconnect technology. The copper interconnects are cladded with a high-permeability layer which is used to focus magnetic flux generated by current flowing through the lines toward the MTJ devices and reduce the power needed for programming. The 25-mm/sup 2/ 1-Mb MRAM circuit operates with address access times of less than 50 ns, consuming 24 mW at 3.0 V and 20 MHz. The 1-Mb MRAM circuit is fabricated in a 0.6-/spl mu/m CMOS process utilizing five layers of metal and two layers of poly. 相似文献
9.
S Abdi LD Traber DN Herndon CS Rogers DL Traber 《Canadian Metallurgical Quarterly》1995,293(4):475-481
We studied the effects of ibuprofen on bronchial blood flow and myocardial function after inhalation injury. Sheep (n = 12) were chronically instrumented with cardiovascular and pulmonary catheters. After 5 days of recovery period, baseline data were collected and the sheep were divided into two groups. Group S (n = 6) were insufflated with 48 breaths of cotton smoke; while group I (n = 6) were pretreated with ibuprofen (12mg/kg bolus followed by 3 mg/kg/h continuous infusion for 24 h) and challenged with the same dose of smoke. All the animals were studied for 24h. Bronchial blood flow increased significantly in both groups throughout the experimental period; while stroke volume as well as right and left ventricular stroke work indices of both groups were significantly decreased (group I worse than group S) in the second half of the experimental period. These data suggest that vasodilatory prostaglandins do not play a major role in the bronchial vascular response to smoke inhalation injury and myocardial depression seen post injury is worse in animals treated with ibuprofen. 相似文献
10.
Rodolfo Villarreal-Calderon Maricela Franco-Lira Angélica González-Maciel Rafael Reynoso-Robles Lou Harritt Beatriz Pérez-Guillé Lara Ferreira-Azevedo Dan Drecktrah Hongtu Zhu Qiang Sun Ricardo Torres-Jardón Mariana Aragón-Flores Ana Calderón-Garcidue?as Philippe Diaz Lilian Calderón-Garcidue?as 《International journal of molecular sciences》2013,14(12):23471-23491
Mexico City Metropolitan Area children and young adults exposed to high concentrations of air pollutants including fine and ultrafine particulate matter (PM) vs. clean air controls, exhibit myocardial inflammation and inflammasome activation with a differential right and left ventricular expression of key inflammatory genes and inflammasomes. We investigated the mRNA expression levels of the prion protein gene PRNP, which plays an important role in the protection against oxidative stress and metal toxicity, and the glucose regulated protein 78, a key protein in endoplasmic reticulum (ER) stress signaling, in ventricular autopsy samples from 30 children and young adults age 19.97 ± 6.8 years with a lifetime of low (n:4) vs. high (n:26) air pollution exposures. Light microscopy and transmission electron microscopy studies were carried out in human ventricles, and electron microscopy studies were also done in 5 young, highly exposed Mexico City dogs. There was significant left ventricular PRNP and bi-ventricular GRP78 mRNA up-regulation in Mexico City young urbanites vs. controls. PRNP up-regulation in the left ventricle was significantly different from the right, p < 0.0001, and there was a strong left ventricular PRNP and GRP78 correlation (p = 0.0005). Marked abnormalities in capillary endothelial cells, numerous nanosized particles in myocardial ER and in abnormal mitochondria characterized the highly exposed ventricles. Early and sustained cardiac ER stress could result in detrimental irreversible consequences in urban children, and while highly complex systems maintain myocardial homeostasis, failure to compensate for chronic myocardial inflammation, oxidative and ER stress, and particles damaging myocardial organelles may prime the development of pathophysiological cardiovascular states in young urbanites. Nanosized PM could play a key cardiac myocyte toxicity role. 相似文献