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Lazar I, Knutsson A, Romero HP, Hektor J, Bushlya V, Mikkelsen A, Lenrick F. Diffusion Bonding 321-Grade Stainless Steel: Failure and Multimodal Characterization. Microsc Microanal 2024; 30:192-199. [PMID: 38525879 DOI: 10.1093/mam/ozae019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 12/01/2023] [Accepted: 02/24/2024] [Indexed: 03/26/2024]
Abstract
Vacuum diffusion-bonded printed circuit heat exchangers are an attractive choice for the high-temperature, high-pressure demands of next-generation energy applications. However, early reports show that the high-temperature materials desired for these applications suffer from poor bond strengths due to precipitation at the bond line, preventing grain boundary migration. In this study, a diffusion bond of the high-temperature stainless steel grade 321H is investigated, and poor mechanical properties are found to be caused by Ti(C, N) precipitation at the bond line. Through in situ studies, it is found that Ti diffuses from the bulk to the mating surfaces at high temperatures. The Ti subsequently precipitates and, for the first time, an interaction between Ti(C, N) and Al/Mg-oxide precipitates at the bond line is observed, where Ti(C, N) nucleates on the oxides forming a core-shell structure. The results indicate that small amounts of particular alloying elements can greatly impact diffusion bond quality, prompting further research into the microstructural evolution that occurs during bonding conditions.
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Affiliation(s)
- Isac Lazar
- Department of Physics, Division of Synchrotron Radiation Research, Lund University, 221 00 Lund, Sweden
| | - Axel Knutsson
- Materials Technology & Chemistry, Alfa Laval, Lund, Sweden
| | | | - Johan Hektor
- Department of Materials Science and Applied Mathematics, Faculty of Technology and Society, Malmö University, 21119 Malmö, Sweden
| | - Volodymyr Bushlya
- Department of Mechanical Engineering Sciences, Division of Production and Materials Engineering, Lund University, 221 00 Lund, Sweden
| | - Anders Mikkelsen
- Department of Physics, Division of Synchrotron Radiation Research, Lund University, 221 00 Lund, Sweden
| | - Filip Lenrick
- Department of Mechanical Engineering Sciences, Division of Production and Materials Engineering, Lund University, 221 00 Lund, Sweden
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Lazar I, Lindvall R, Lenrick F, Bushlya V, Ek M. Characterisation of worn WC tool using STEM-EDS aided by principal component analysis. J Microsc 2021; 283:64-73. [PMID: 33788272 DOI: 10.1111/jmi.13009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/06/2021] [Accepted: 03/23/2021] [Indexed: 11/29/2022]
Abstract
Interdiffusion and chemical reactions contribute to tool wear in metal machining. Increased understanding of these processes, through characterisation of worn tools, can facilitate design of more resilient materials through chemical and diffusional passivation. However, the unknown reaction conditions, the large number of elements, and the formation of interspersed phases makes for a complex analysis. Here, we demonstrate the use of scanning transmission electron microscopy and energy dispersive X-ray spectroscopy for characterising the interaction layer between a titanium alloy and a cemented carbide tool. Principal component analysis is used to find chemical correlations and help separate signals from embedded phases. Crucially, we evaluate the required X-ray count statistics from simulated spectrum images and theory prior to the experiment. We find no indications of intermediate phases between the original WC and the metallic W interaction layer. Furthermore, we find enrichment of minor constituents in the titanium alloy closest to the tool which alter the solubility of out-diffusing species, suggesting strong interrelations between the diffusion processes.
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Affiliation(s)
- Isac Lazar
- Centre for Analysis and Synthesis, Lund University, Lund, Sweden.,Division of Production and Materials Engineering, Lund University, Lund, Sweden
| | - Rebecka Lindvall
- Division of Production and Materials Engineering, Lund University, Lund, Sweden
| | - Filip Lenrick
- Division of Production and Materials Engineering, Lund University, Lund, Sweden
| | - Volodymyr Bushlya
- Division of Production and Materials Engineering, Lund University, Lund, Sweden
| | - Martin Ek
- Centre for Analysis and Synthesis, Lund University, Lund, Sweden
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Patel PA, Liang C, Arora A, Vijayan S, Ahuja S, Wagley PK, Settlage R, LaConte LEW, Goodkin HP, Lazar I, Srivastava S, Mukherjee K. Haploinsufficiency of X-linked intellectual disability gene CASK induces post-transcriptional changes in synaptic and cellular metabolic pathways. Exp Neurol 2020; 329:113319. [PMID: 32305418 DOI: 10.1016/j.expneurol.2020.113319] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 04/04/2020] [Accepted: 04/15/2020] [Indexed: 12/17/2022]
Abstract
Heterozygous mutations in the X-linked gene CASK are associated with intellectual disability, microcephaly, pontocerebellar hypoplasia, optic nerve hypoplasia and partially penetrant seizures in girls. The Cask+/- heterozygous knockout female mouse phenocopies the human disorder and exhibits postnatal microencephaly, cerebellar hypoplasia and optic nerve hypoplasia. It is not known if Cask+/- mice also display seizures, nor is known the molecular mechanism by which CASK haploinsufficiency produces the numerous documented phenotypes. 24-h video electroencephalography demonstrates that despite sporadic seizure activity, the overall electrographic patterns remain unaltered in Cask+/- mice. Additionally, seizure threshold to the commonly used kindling agent, pentylenetetrazol, remains unaltered in Cask+/- mice, indicating that even in mice the seizure phenotype is only partially penetrant and may have an indirect mechanism. RNA sequencing experiments on Cask+/- mouse brain uncovers a very limited number of changes, with most differences arising in the transcripts of extracellular matrix proteins and the transcripts of a group of nuclear proteins. In contrast to limited changes at the transcript level, quantitative whole-brain proteomics using iTRAQ quantitative mass-spectrometry reveals major changes in synaptic, metabolic/mitochondrial, cytoskeletal, and protein metabolic pathways. Unbiased protein-protein interaction mapping using affinity chromatography demonstrates that CASK may form complexes with proteins belonging to the same functional groups in which altered protein levels are observed. We discuss the mechanism of the observed changes in the context of known molecular function/s of CASK. Overall, our data indicate that the phenotypic spectrum of female Cask+/- mice includes sporadic seizures and thus closely parallels that of CASK haploinsufficient girls; the Cask+/- mouse is thus a face-validated model for CASK-related pathologies. We therefore surmise that CASK haploinsufficiency is likely to affect brain structure and function due to dysregulation of several cellular pathways including synaptic signaling and cellular metabolism.
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Affiliation(s)
- P A Patel
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States; Graduate Program in Translational Biology, Medicine, and Health, Virginia Tech, Blacksburg, VA, United States
| | - C Liang
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States
| | - A Arora
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States
| | - S Vijayan
- School of Neuroscience, Virginia Tech, Blacksburg, VA, United States
| | - S Ahuja
- Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | - P K Wagley
- Neurology, University of Virginia, Charlottesville, VA, USA
| | - R Settlage
- Advanced Research Computing, Virginia Tech, Blacksburg, VA, United States
| | - L E W LaConte
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States
| | - H P Goodkin
- Neurology, University of Virginia, Charlottesville, VA, USA
| | - I Lazar
- Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | - S Srivastava
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States
| | - K Mukherjee
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States; Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States; Department of Psychiatry and Behavioral Medicine, Virginia Tech Carilion School of Medicine, Roanoke, VA, United States.
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Lazar I, Abukaf H, Sofer S, Peled N, Leibovitz E. Impact of Conversion from an Open Ward Design Paediatric Intensive Care Unit Environment to All Isolated Rooms Environment on Incidence of Bloodstream Infections and Antibiotic Resistance in Southern Israel (2000 to 2008). Anaesth Intensive Care 2015; 43:34-41. [DOI: 10.1177/0310057x1504300106] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We studied the epidemiology, microbiology, clinical aspects and outcome of bloodstream infections (BSI) in a tertiary paediatric intensive care unit. All BSI episodes were prospectively identified and analysed. The paediatric intensive care unit moved in 2006 from an open-plan unit to a new (all single room) unit. Three hundred and fifty-three BSI episodes occurred in 299 of 4162 patients. Overall, BSI incidence was 85 per 1000 hospitalised children. Fewer BSI episodes occurred during the last two years of the study (2007 to 2008), compared with 2000 to 2006 (70 of 1061 admissions, 6.5% versus 283 of 3101 admissions, 9.1%, respectively, P=0.01). There were 127 of 340 (37.4%) community-acquired and 213 of 340 (62.6%) nosocomial BSI episodes (31 of 1000 and 51 of 1000, respectively). Nosocomial BSI episodes decreased during 2007 to 2008 versus 2000 to 2006 (37.7% versus 55.8%, P=0.03). In 448 instances, pathogens were isolated, 231 (52%) Gram-positive and 188 (42%) Gram-negative. Coagulase-negative Staphylococci, S. pneumoniae and S. aureus (41.1%, 19.9% and 11.7%, respectively) were the most common Gram-positive and Enterobacteriaceae spp. the most frequent Gram-negative organisms (45.2%, of them Klebsiella spp. and E. coli 40% and 29.4%, respectively). A significant decrease was recorded during 2007 to 2008 in Enterobacteriaceae resistance to piperacillin, gentamicin and ciprofloxacin. Thirty of 299 (10%, 9 with S. pneumoniae-BSI) patients died. A significant decrease in BSI and nosocomial incidence and Enterobacteriaceae spp. antibiotic resistance was recorded following the conversion of the paediatric intensive care unit from an open ward to an all isolated rooms environment.
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Affiliation(s)
- I. Lazar
- Pediatric Intensive Care Unit, Soroka University Medical Center, Ben-Gurion University, Beer-Sheva, Israel
| | - H. Abukaf
- Pediatric Emergency Medicine Department, Soroka University Medical Center, Ben-Gurion University, Beer-Sheva, Israel
| | - S. Sofer
- Pediatric Intensive Care Unit, Soroka University Medical Center, Ben-Gurion University, Beer-Sheva, Israel
| | - N. Peled
- Microbiology Department, Soroka University Medical Center, Ben-Gurion University, Beer-Sheva, Israel
| | - E. Leibovitz
- Pediatric Emergency Medicine Department, Soroka University Medical Center, Ben-Gurion University, Beer-Sheva, Israel
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Harangi B, Lazar I, Hajdu A. Automatic exudate detection using active contour model and regionwise classification. Annu Int Conf IEEE Eng Med Biol Soc 2013; 2012:5951-4. [PMID: 23367284 DOI: 10.1109/embc.2012.6347349] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Diabetic retinopathy is one the most common cause of blindness in the world. Exudates are among the early signs of this disease, so its proper detection is a very important task to prevent consequent effects. In this paper, we propose a novel approach for exudate detection. First, we identify possible regions containing exudates using grayscale morphology. Then, we apply an active contour based method to minimize the Chan-Vese energy to extract accurate borders of the candidates. To remove those false candidates that have sufficient strong borders to pass the active contour method we use a regionwise classifier. Hence, we extract several shape features for each candidate and let a boosted Naïve Bayes classifier eliminate the false candidates. We considered the publicly available DiaretDB1 color fundus image set for testing, where the proposed method outperformed several state-of-the-art exudate detectors.
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Affiliation(s)
- B Harangi
- University of Debrecen, Faculty of Informatics, Debrecen, 4010 POB. 12, Hungary.
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Lazar I, Cavari Y, Rosenberg E, Knyazer B. Horner's syndrome in patients admitted to the paediatric intensive care unit: epidemiology, diagnosis and clinical practice. Anaesth Intensive Care 2013; 41:20-3. [PMID: 23362886 DOI: 10.1177/0310057x1304100105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Horner's syndrome appears when the three-neuron sympathetic pathway is interrupted anywhere from the posterior-lateral nuclei of the hypothalamus through the spinal cord to the eye. In children, Horner's syndrome can be either congenital or acquired, but overall it is a rare finding. There are several causes of Horner's syndrome, some of iatrogenic. Although uncommon in the paediatric population, prompt recognition of the syndrome and immediate treatment may prevent permanent damage to the neuronal pathway. Awareness of the risk of developing iatrogenic Horner's syndrome and early detection of signs are recommended to minimise future disability.
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Affiliation(s)
- I Lazar
- Ben-Gurion University of the Negev, Beer Sheva, Israel.
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Lazar I, Cavari Y, Sofer S. Noninvasive positive pressure ventilation in infants with respiratory failure. Crit Care 2009. [PMCID: PMC4083894 DOI: 10.1186/cc7172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- I Lazar
- Soroka Medical Center and Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Y Cavari
- Soroka Medical Center and Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - S Sofer
- Soroka Medical Center and Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
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Lazar I. Livin, a regulator of apoptosis protein, is deregulated in melanoma and serves as an independent prognostic factor—a study of 114 melanoma patients. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.21006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
21006 Background: Inhibitor of Apoptosis Proteins (IAP) family members inhibit apoptosis mainly by direct binding and inhibition of caspases. We previously identified the IAP Livin and demonstrated that following strong apoptotic stimuli the protein was cleaved by effector caspases to produce a truncated form with paradoxical pro-apoptotic activity. We also demonstrated that Livin is overexpressed in melanoma (M) and plays a role in chemoresistance and survival. More recently we identified synonymous single nucleotide polymorphism (SNP) in Livin at position 528(C/T) that determines expression levels of Livin protein. We found that Livin is expressed in a monoalleic manner. Normal heterozygous samples express the 528T mRNA allele and the Livin protein is not expressed. The monoallelic regulation is lost in metastatic M and the Livin protein is expressed. Methods: This study included 114 M patients that were grouped into clinical categories according to prognosis. Correlation between Livin expression and clinical parameters was examined using ANOVA, chi-square test and Kaplan-Mayer curves. Results: We found that in primary cultures from 114 M patients high, low and absence of Livin protein expression were associated with the T/C, CC and TT genotypes, respectively, at the 528(C/T) polymorphic site. Correlation of Livin expression with overall survival was significant: high expression of the Livin protein was associated with bad prognosis; survival in patients with medium expression of Livin was significantly longer compared with those without livin expression For 23 patients samples were obtained both at diagnosis and upon disease progression. All 23 first tumor sample did not express the Livin protein. Remarkably, Livin was expressed in second tumor samples from 9 of the 23 patients.and was associated with poor prognosis. Conclusions: We found that Livin expression is an independent prognosis factor in malignant M. furthermore, we describe a direct correlation between the level of Livin protein expression and survival of M patients. We also provide evidence for a novel mechanism associating synonymous SNP with control over protein expression and its deregulation during tumor progression. No significant financial relationships to disclose.
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Affiliation(s)
- I. Lazar
- Hadassah University Hospital, Jerusalem, Israel
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9
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Abstract
The aim of the study was to investigate the place of imaging in the diagnosis and treatment of acute appendicitis. The files of 2,427 children with suspected acute appendicitis were reviewed for clinical management and operative findings. The sample was divided into 3 groups at time of admission: (1) before diagnostic imaging was available in our department (1991-1994); (2) after the introduction of imaging studies on a random basis in equivocal cases (1995-1998); and (3) after a policy was formulated for ultrasound use in all equivocal cases followed by computed tomography if necessary (1999-2000). Results showed that the rate of misdiagnosis decreased from 13.2% in group 1 to 6.5% in group 2 and 6.1% in group 3. False-positive findings (normal appendix with positive scan) were noted in 16.7% of group 2 and 25% of group 3; false-negative findings (appendicitis at surgery with negative scan) in 23.8% and 9.5%, respectively. Computed tomography was performed in 8 children and prevented unnecessary surgery in 4 of them. We conclude that in equivocal cases of acute appendicitis, imaging studies performed by skilled operators can improve the accuracy of diagnosis, saving patients unnecessary surgery, and identifying other conditions that mimic appendicitis.
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Affiliation(s)
- G Even-Bendahan
- Department of Pediatric Surgery, Sapir Medical Center, Meir Hospital, Kfar Saba, Israel
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Abstract
Dissection of the portal vein is a rare entity which has been rarely described during transjugular intrahepatic portosystemic shunt (TIPS) procedure. We report three cases of dissection during this procedure and their complications. One dissection was immediately treated with coaxial stents. The two others were complicated either by a thrombus or by a false aneurysm. In the first case a second parallel stent was used to treat this complication. The patient with the portal vein false aneurysm was transplanted 4 days after this diagnosis. Portal vein dissection in TIPS procedure appeared to be less rare than has been reported and must be considered as a potential cause of TIPS dysfunction.
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Affiliation(s)
- P Petit
- Service Central de Radiologie et Imagerie Médicale, Groupe Hospitalier de la Timone, Marseille, France
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Gruzelier J, Clow A, Evans P, Lazar I, Walker L. Mind-body influences on immunity: lateralized control, stress, individual differences predictors, and prophylaxis. Ann N Y Acad Sci 1998; 851:487-94. [PMID: 9668642 DOI: 10.1111/j.1749-6632.1998.tb09027.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J Gruzelier
- Department of Psychology and Cognitive Neuroscience, Imperial College of Science, Technology and Medicine, Charing Cross Hospital, London, United Kingdom.
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Butwell NB, Ramasamy R, Lazar I, Sherry AD, Malloy CR. Effect of lidocaine on contracture, intracellular sodium, and pH in ischemic rat hearts. Am J Physiol 1993; 264:H1884-9. [PMID: 8322918 DOI: 10.1152/ajpheart.1993.264.6.h1884] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The relationships among intracellular Na concentration ([Na+]i), intracellular pH, [ATP], and contracture during global ischemia were studied in isolated, perfused rat hearts. Intracellular Na was monitored by 23Na nuclear magnetic resonance (NMR) spectroscopy using thulium 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetra(methylene phosphonate) (TmDOTP5-) as the paramagnetic shift reagent. High-energy phosphates and pH were monitored under the same conditions using 31P-NMR spectroscopy. Lidocaine (130 microM), a class IB fast Na channel blocker known to protect ischemic myocardium, prolonged the time to contracture in both unpaced and paced hearts (240 beats/min). After 10 min of global ischemia in paced hearts, [Na+]i was lower in the lidocaine-treated group compared with untreated hearts. The addition of lidocaine also significantly attenuated the depletion of ATP as well as development of intracellular acidosis. At the time of contracture, however, there was no difference in [Na+]i or pH between the two groups. Interestingly, the effect of lidocaine on Na+i accumulation during ischemia was manifested during the first 5-10 min of ischemia, while its effect on pH occurred after 9 min. This finding suggests that a mechanism other than the Na-H exchanger may play a role in the accumulation of Na+i early in the course of ischemia.
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Affiliation(s)
- N B Butwell
- Department of Radiology, Mary Nell and Ralph B. Rogers Magnetic Resonance Center, University of Texas Southwestern Medical Center, Dallas
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Abstract
In vivo sodium-23 and hydrogen-1 magnetic resonance (MR) imaging and spectroscopy of the rat brain during infusion of the shift reagent thulium DOTP5- (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetra[methylene phosphonate] was performed to assign the various peaks observed during infusion and to evaluate the shift reagent in discriminating tissue compartments. Na-23 spectra collected during the infusion showed two shifted peaks that were assigned to intravascular Na+ and extracellular muscle Na+, respectively, and one unshifted peak assigned to intra- and extracellular brain Na+ and cerebrospinal fluid Na+. These assignments were validated with H-1 and Na-23 MR imaging and Na-23 chemical shift imaging (CSI). The H-1 and Na-23 images showed that a surface coil placed on a rat head can detect a substantial amount of signal from muscle surrounding the skull. Na-23 CSI spectra from successive 1-mm-thick coronal sections indicated that the shift reagent did not cross the blood-brain barrier. The study also showed that bulk susceptibility shifts are quite small with Tm-DOTP5-. This reagent may be useful in determining compartmental Na+ concentrations and blood flow kinetics in brain and in examining the integrity of the blood-brain barrier.
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Affiliation(s)
- N Bansal
- Mary Nell and Ralph B. Rogers Magnetic Resonance Center, Department of Radiology, University of Texas Southwestern Medical Center, Dallas 75235-9085
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Abstract
1,4,7-Triazacyclononane-N,N',N''-tris(methylenephosphonate monoethylester) (NOTPME) has been synthesized, characterized and analyzed for use as a 31P NMR indicator of intracellular Mg2+ and Zn2+ ions. The 31P NMR spectrum of this chelate in the presence of metal ions shows characteristic resonances for the free chelate, Mg(NOTPME)-, Zn(NOTPME)-, and Ca(NOTPME)-. The Kd values indicate that this chelate has a 10-fold higher affinity for Mg2+ than for Ca2+ at physiological pH values. In the presence of Mg2+, NOTPME is readily loaded into red blood cells. A 31P NMR spectrum of red cells taken after several washings shows resonances characteristic of entrapped NOTPME and the Mg(NOTPME)- complex, the relative areas of which report an intracellular free Mg2+ concentration of 0.32 mM. The 31P chemical shifts of the free chelate and its metal complexes are far downfield from the typical phosphorus-containing metabolites observed in biological systems, thus making it possible to monitor intracellular cation concentrations and cell energetics simultaneously.
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Affiliation(s)
- R Ramasamy
- Department of Chemistry, University of Texas at Dallas, Richardson 75083-0688
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Lazar I. Ch. A-1 MEOR Field Trials Carried Out Over the World During the Last 35 Years. microbial enhancement of oil recovery—recent advances, Proceedings of the 1990 international conference on microbial enhancement of oil recovery 1991. [DOI: 10.1016/s0376-7361(09)70181-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Lazar I. Standby power for critical areas: hospitals. Consult Specif Eng 1990; 7:50-5. [PMID: 10103790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Selecting an emergency standby power system for critical areas is a task requiring a thorough knowledge of available systems and the loads that must be covered.
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Abstract
This study was carried out to investigate the renal handling of d- and l-lactate and the extent of their metabolism in men. Ten healthy male subjects were given an intravenous (IV) infusion of a racemic mixture of d- and l-lactate. At an infusion rate of 1.0 to 1.3 meq/kg body weight of each isomer, d-lactate achieved a concentration in plasma of 1.7 to 3.0 meq/L, and l-lactate 2.8 to 4.2 meq/L. At these levels, fractional excretion of d-lactate ranged from 40% to 65%, while fractional excretion of l-lactate was always less than 5%. At a higher infusion rate, 1.8 to 2.0 meq/kg/h, plasma concentrations of d- and l-lactate reached 4.5 to 6.0 meq/L, and 4.0 to 6.7 meq/L, respectively. Fractional excretion of d-lactate then ranged from 61% to 100%, while that of l-lactate ranged from 9% to 30%. At plasma concentrations of d-lactate less than 3.0 meq/L, reabsorption of l-lactate was nearly complete, but when plasma d-lactate exceeded 3.0 meq/L, reabsorption of l-lactate was considerably impaired. Similarly, for a given concentration of plasma d-lactate, its reabsorption was more efficient when the plasma l-lactate concentration and fractional excretion of l-lactate were low than when they were high. At an infusion rate of d-lactate of 1.0 to 1.3 meq/L, about 90% of the infused lactate was metabolized, and at a higher infusion rate, still more than 75% of the infused lactate was metabolized.(ABSTRACT TRUNCATED AT 250 WORDS)
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Taintor Z, Strain JJ, Lazar I, Gise LH, Spikes J, Deucker R, Ellsworth G. Evaluation of training in geriatric consultation: development of assessment measures. Gerontol Geriatr Educ 1984; 5:73-81. [PMID: 6536554 DOI: 10.1300/j021v05n01_08] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Abstract
Children from low-income minority families participated in early childhood education programs conducted in the 1960s and 1970s by members of the Consortium for Longitudinal Studies. Data on program impact from early childhood to young adulthood revealed direct, positive effects on standardized tests, school competence, attitudes toward achievement, high school completion, and occupational attitudes. Indirect program effects were found on occupational attainment.
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Lazar I. Guidelines to follow to monitor and control electrical energy losses. Specif Eng 1982; 48:64-9. [PMID: 10257664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Lazar I. On the perceptual distortion of data: early intervention programs are effective in overcoming environmental deprivation. Pediatrics 1981; 68:613-4. [PMID: 6459564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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Lazar I, Karasu TB. Evaluation and management of depression in the elderly. Geriatrics (Basel) 1980; 35:47-53. [PMID: 7429159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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Darlington RB, Royce JM, Snipper AS, Murray HW, Lazar I. Preschool Programs and Later School Competence of Children from Low-Income Families. Science 1980; 208:202-4. [PMID: 17745540 DOI: 10.1126/science.208.4440.202] [Citation(s) in RCA: 103] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
At follow-up in 1976, low-income children who had attended infant and preschool programs in the 1960's had significantly higher rates of meeting school requirements than did controls, as measured by lower frequency of placement in special education classes and of being retained in grade (held back).
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Deacetis LA, Einstein FS, Juliano RA, Lazar I. Single strip diffraction: comparison of Kirchhoff theory and geometrical theory with the exact solution in the limit of small glancing angle and width; perpendicular polarization. Appl Opt 1976; 15:2866-2870. [PMID: 20165503 DOI: 10.1364/ao.15.002866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A comparison is made between approximations using the geometrical theory of diffraction (GTD) and Kirchhoff theory and the exact solution using Maxwell's equations for the case of Fraunhofer diffraction of electromagnetic radiation incident upon a long, thin, perfectly conducting strip with the electric field vector polarized perpendicular to the strip axis. Strip widths from approximately 0.3lambda to 3lambda are considered. Glancing angles of incidence are taken from 4 degrees to 90 degrees . Irradiances are compared as a function of diffraction angle in the region on the same side of the strip as the incident radiation.
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Deacetis LA, Lazar I. Experimental diffraction by two long, parallel strips in a plane: 2: horizontal polarization. Appl Opt 1973; 12:2804-2806. [PMID: 20125869 DOI: 10.1364/ao.12.002804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Deacetis LA, Lazar I. Single Strip Diffraction: Comparison Between Kirchhoff Theory and Keller's Geometrical Theory in the Limit of Small Glancing Angle and Width. Appl Opt 1970; 9:1691-1694. [PMID: 20076443 DOI: 10.1364/ao.9.001691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A comparison is made between the approximate theories of Kirchhoff and Keller, and the exact solution of Maxwell's equations for the case of Fraunhofer diffraction of electromagnetic radiation incident upon a long, thin conducting strip with the electric field vector polarized parallel to the strip axis. Strip widths from approximately 0.3lambda to 3lambda are considered with angles of incidence ranging from 4 degrees to 84 degrees . The predieted intensities are compared as a function of angle in the region on the same side of the strip as the incident radiation. It is found that in the limits of small glancing angle or small strip width, where both approximate theories are of questionable validity, Keller's geometrical theory more closely agrees with the exact solution.
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Lazar I, Deacetis LA. Experimental diffraction by two long, parallel strips in a plane. I: vertical polarization. Appl Opt 1968; 7:1609-1612. [PMID: 20068846 DOI: 10.1364/ao.7.001609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Fraunhofer diffraction by two long, thin, parallel conducting strips in a plane is investigated experimentally using microwaves whose wavelength is of the order of the strip width. The radiation is polarized with the electric field parallel to the axes of the strips. The results are compared with scalar Kirchhoff theory and first and second order Keller theory. It is found that for this polarization each theory yields good agreement with the results obtained in the laboratory.
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Affiliation(s)
- I Lazar
- City University of New York, USA
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Barber C, Lazar I, Meitert E. Contribution à l’étude des relations entre corynébactéries diphthériques et corynébactéries phytopathogènes. Pathobiology 1966. [DOI: 10.1159/000161889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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