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Selected AbstractsPrediction of two-phase flow distribution in parallel pipes using stability analysisAICHE JOURNAL, Issue 10 2006L. Pustylnik Abstract Two-phase gas liquid flow in pipes is a complex process. One of the problems that is hardly understood is how the two phases are distributed among two or more parallel lines with a common inlet manifold. Steady-state analysis yields multiple steady-state solutions. Linear and nonlinear (simulation) stability analyses are performed in order to determine the actual distribution of the flow that will take place in a real system. The analysis shows that when there are four parallel pipes, for example, the two-phase flow mixture from the common inlet manifold can choose to flow in one, two, three, or in all four pipes, depending on the flow rates of the liquid, and the gas and on the pipes inclination. For low-flow rates of gas and liquid, the flow tends to take place only in one line, while stagnant liquid columns are present in the other three pipes. As the flow rate increases the flow will take place in 2, 3 and finally in 4 pipes. Experimental data confirm the analysis although matching is only approximate. © 2006 American Institute of Chemical Engineers AIChE J, 2006 [source] Identification of immunodominant CD4+ T cell epitopes in patients with Yersinia -induced reactive arthritis by cytometric cytokine secretion assayARTHRITIS & RHEUMATISM, Issue 11 2006Andreas Thiel Objective In reactive arthritis (ReA), a bacteria-specific T cell response to the triggering microbe is detected in synovial fluid. So far, direct characterization of bacteria-specific T cells and identification of the immunodominant fine specificities remain difficult due to the lack of appropriate techniques. The aim of the present study was to directly determine the fine specificity of CD4+ T cells specific to ReA-associated bacteria-derived protein. Methods In 2 patients with Yersinia -induced ReA, live Yersinia Hsp60,specific CD4+ T cells were directly isolated from synovial fluid after stimulation with Yersinia -derived protein Hsp60 using a cytometric cytokine secretion assay. Generated short-term T cell lines were then tested in vitro for their peptide epitope specificity. Also, direct cross-reactivity of one line with Chlamydia - and human-derived Hsp60 was assessed. Results Generated short-term CD4+ T cell lines were highly antigen-specific and revealed single immunodominant peptide epitopes that were confirmed by direct testing with single peptides in both peripheral blood and synovial fluid cells. Yersinia Hsp60,specific T cells of one patient cross-reacted directly with human Hsp60. Conclusion Our results demonstrate the feasibility of direct assessment of live, potentially pathogenic, antigen-specific interferon-,+ CD4+ T cells taken from inflammatory lesions of patients with rheumatic diseases such as ReA. This might have implications not only regarding pathogenesis, but also in the design of new immunotherapies. [source] Probing small scale structure in the atmosphere of V471 TauriASTRONOMISCHE NACHRICHTEN, Issue 3 2004F. M. Walter Abstract The white dwarf in the eclipsing binary system V471 Tau is viewed through the atmosphere of the active K star prior to ingress and after egress. In the far UV the surface brightness of the hot white dwarf far outshines the K star emission. We can use this to probe the structure of the extended K star atmosphere along one line of sight, in absorption, on spatial scales of the radius of the white dwarf (10,000 km). The time series of HST/STIS spectra which show a hot (>250,000 K) extended (>1 K star radius) atmosphere around the K star. We see discrete structures in the velocity-resolved spectra, on spatial scales of less than 100,000 km. The mean velocity is that expected of gas in co-rotation with the K star, but the discrete velocity structures have excursions of up to 70 km/s from the mean. The mean temperature seems to increase with height above the K star photosphere. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Impairment of double-strand breaks repair and aberrant splicing of ATM and MRE11 in leukemia,lymphoma cell lines with microsatellite instabilityCANCER SCIENCE, Issue 3 2006Maria Francisca Ham Mutations of DNA double-strand breaks (DSB) repair genes, ATM, MRE11, RAD50, NBS1 and ATR, are postulated to play a role in the development of gastrointestinal malignancies with an impaired mismatch repair (MMR) function. In the present study, mutations of these genes together with the presence of microsatellite instability (MSI) were examined in 50 leukemia,lymphoma cell lines. MSI was detected in 13 (26%) lines. Mutations of intronic mononucleotide repeats in ATM and MRE11 were found in nine and six lines, respectively, whereas mutations of mononucleotide repeats of RAD50 were found in only one line, and none were found in either NBS1 or ATR. Frequencies of ATM and MRE11 mutations were significantly higher in MSI-positive than MSI-negative lines. These mutations generated aberrant splicing in both genes. The intensity of the aberrant transcript of ATM (497del22) was stronger in five lines harboring mononucleotide mutations of 2 bp or more than in the lines without or with a 1-bp mutation. The intensity of the aberrant transcript of MRE11 (315del88) was stronger in four lines with mononucleotide mutations than in lines without. The expression levels of ATM and MRE11 transcripts in MSI-positive lines were significantly higher than those in MSI-negative lines. MSI-positive cell lines showed delay or abrogation of DSB repair. The present study suggests that impairment of the MMR system causes aberrant transcripts in the DSB repair genes ATM and MRE11. This might result in inactivation of the DSB repair system, thus inducing an acceleration of genome instability and accumulation of genetic damage. (Cancer Sci 2006; 97: 226,234) [source] Optimal projection estimation for transcatheter aortic valve implantation based on contrast-aortography,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2010Validation of a Prototype Software Abstract We investigate the accuracy of a new software system (C-THV, Paieon) designed to calculate the optimal projection (OP) view for transcatheter aortic valve implantation (TAVI) based on two aortograms, and its agreement with the operator's choice. An optimal fluoroscopic working view projection with all three aortic cusps depicted in one line, is crucial during TAVI. In our institution selection of the OP is based on multislice computed tomography (MSCT). Seventy-three consecutive patients referred for TAVI were divided into two groups. For the first group (53 patients, retrospective cohort) we compared the OP views estimated by C-THV with the ones estimated by MSCT. For the second group (20 patients, prospective cohort), we compared the OP views estimated by C-THV with the operator's choice during TAVI. For the retrospective cohort, the mean absolute difference (mean ± SD) between C-THV and MSCT was 6.6 ± 4.9 degrees. In 77% of the cases the mean difference between C-THV and MSCT was <10 degrees. For the prospective cohort, the mean absolute difference (mean ± SD) between C-THV and the operator's choice was 5.5 ± 3.4 degrees. A mean difference of <10 degrees was found in 90% of the cases. In this study we found that the C-THV software estimated the OP view for TAVI with good accuracy. The level of agreement between C-THV and either the MSCT or the operator's choice was deemed satisfactory, with the vast majority of observed differences being <10 degrees. © 2010 Wiley-Liss, Inc. [source] 4423: The limits of manifest refraction: visual performance under low light conditionsACTA OPHTHALMOLOGICA, Issue 2010J CABEZA Purpose To present a method to optimize the prescription values of ophthalmic lenses based on ocular wavefront information. Those lenses provide improved vision under low light conditions to the patient. Methods We will show first the influence of ocular aberrations on visual performance, and how do they change with pupil size. We will also show the way higher order aberrations affect the manifest refraction procedure. Finally, we will present a method to optimize the prescription values of ophthalmic lenses based on ocular wavefront information. Results Independent studies have shown that such optimized ophthalmic lenses provide on average an improvement in visual acuity of almost one line under mesopic conditions, when compared to conventional opththalmic lenses. Conclusion Visual performance under low light conditions can be improved by ophthalmic lenses whose prescription was optimized taking into account ocular wavefront information. Commercial interest [source] PaCE: a technique to avoid subretinal fluid drainage in retinal detachment surgeryACTA OPHTHALMOLOGICA, Issue 1 2006Manzar Saeed Abstract. Purpose:,Subretinal fluid (SRF) drainage and thus the potential complications of this procedure during scleral buckling can be avoided by inducing SRF absorption preoperatively. The technique described in this series is named PaCE (Pneumatic Cryo Explant). Methods:,A total of 22 eyes of 22 patients with primary bullous rhegmatogenous retinal detachment (RRD) were included in this prospective non-comparative case trial. All satisfied specific inclusion criteria similar to those used in previous pneumatic retinopexy (PR) studies. Under direct visualization, 0.3 ml C3F8 100% was injected into the vitreous cavity through the pars plana. Postoperative posturing was encouraged. Retinopexy with either cryotherapy or laser was performed, combined with scleral buckling (SB) when the SRF was absorbed. Avoidance of SRF drainage and persistent reattachment of the retina at the end of the 12-month follow-up was considered a successful outcome. A change in vision by one line (logMAR) was considered significant. Results:,Resolution of SRF before retinopexy and the SB procedure was achieved in 20 of 22 eyes (90.9%) and hence SRF drainage was not required. Visual improvement was achieved in 95% of cases. One eye (4.5%) lost vision due to a total RD after gas injection (further surgery was not carried out). Conclusion:,PaCE should be considered in any suitable case of primary RRD where SRF drainage is deemed necessary. The potential complications associated with this procedure are relatively less serious and it does not compromise the viability of subsequent procedures. [source] Vitrectomy without postoperative posturing for idiopathic macular holesCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 5 2007Adrian Rubinstein MRCSEd Abstract Purpose:, To determine the success of vitrectomy with ILM peeling and C3F8 tamponade for macular holes without the need for postoperative face-down posturing. Methods:, Twenty-four eyes of 24 consecutive patients undergoing pars plana vitrectomy with indocyanine green-assisted ILM peeling and C3F8 tamponade without prone posturing were included in the study. All patients had follow up on 1 day, 2 weeks and 3 months postoperatively. Biomicroscopy and optical coherence tomography were used to assess macular hole closure at 3 months postoperatively. Snellen visual acuity was compared pre- and postoperatively. Results:, Of the 24 eyes recruited, two (8%) had stage II, 17 (71%) had stage III and five (21%) had stage IV macular holes. Nineteen (79%) eyes were phakic and five (21%) eyes were pseudophakic at the time of surgery. The macular holes had been present for an average of 7.5 months (range 3,18 months). At 3-month follow up, 22/24 (91.6%) holes were closed. Both of the two holes that failed to close were stage IV macular holes. Preoperative visual acuity ranged from 6/18 to 6/60 (mean 6/36). Postoperative visual acuity ranged from 6/9 to 6/60 (mean 6/18). Eighteen eyes had improvement of visual acuity of at least one line on the Snellen chart, six eyes had no improvement. No eyes had worse vision postoperatively. Conclusion:, Macular hole surgery without face-down posturing provides anatomical and functional results comparable to those with prone posturing. Combined phacovitrectomy is not essential to avoid prone posturing. 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