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Complex Defect (complex + defect)
Selected AbstractsHigh resolution Laplace deep level transient spectroscopy of p-type polycrystalline diamondPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 9 2008N. Mitromara Abstract High resolution Laplace deep level transient spectroscopy (LDLTS) has been used to characterise deep electronic states in the band gap of polycrystalline p-type diamond. The thin diamond films were grown by the hot-filament chemical vapour deposition (HFCVD) technique on p-type and n-type Si for the formation of the Schottky and p,n diodes respectively. The B concentration in the diamond films ranged from 7 × 1018 cm,3 to 7 × 1021 cm,3. Conventional capacitance DLTS showed a fairly narrow peak at about 180 K from the diamond grown on p-type Si, but further analysis with LDLTS shows that this peak originates from a complex defect with up to three hole emission rates. In the case of the Schottky diode, these emission rates do not vary much with temperature which indicates that they may be due to the presence of an extended defect, where the valence band itself is changing its profile as the traps capture more carriers. LDLTS of a similar trap in the diamond grown on n-type Si also shows three emission rates, which do not vary as expected with temperature. The results are discussed in terms of defects existing in the strain fields of grain boundaries, and exhibiting non point-defect like properties. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Recurrent respiratory papillomatosis: a complex defect in immune responsiveness to human papillomavirus-6 and -11APMIS, Issue 6-7 2010VINCENT R. BONAGURA Bonagura VR, Hatam LJ, Rosenthal DW, DeVoti JA, Lam F, Steinberg BM, Abramson AL. Recurrent respiratory papillomatosis: a complex defect in immune responsiveness to human papillomavirus-6 and -11. APMIS 2010; 118: 455,470. Recurrent respiratory papillomatosis (RRP) is a rare disease of the larynx caused by infection with human papillomaviruses (HPV) -6 or -11, associated with significant morbidity and on occasion mortality. Here we summarize our current understanding of the permissive adaptive and innate responses made by patients with RRP that support chronic HPV infection and prevent immune clearance of these viruses. Furthermore, we provide new evidence of TH2-like polarization in papillomas and blood of patients with RRP, restricted CD4 and CD8 V, repertoires, the effect of HPV-11 early protein E6 on T-cell alloreactivity, enriched Langerhans cell presence in papillomas, and evidence that natural killer cells are dysfunctional in RRP. We review the immunogenetic mechanisms that regulate the dysfunctional responses made by patients with RRP in response to HPV infection of the upper airway. In addition, we are identifying T-cell epitopes on HPV-11 early proteins, in the context of human leukocyte antigen (HLA) class II alleles enriched in RRP that should help generate a therapeutic vaccine. Taken together, RRP is a complex, multigene disease manifesting as a tissue and HPV-specific, immune deficiency that prevents effective clearance and/or control of HPV-6 and -11 infection. [source] Evaluation of renal function in children with mitochondrial respiratory chain complex defect: usefulness of cystatin CACTA PAEDIATRICA, Issue 6 2009Soon Min Lee Abstract Aim: Mitochondrial disorders with respiratory chain complex defect are known to show a broad spectrum of clinical phenotypes, though their contribution to renal disease has not received much attention. The aim of this study was to evaluate renal function using different markers of the glomerular filtration rate (GFR) in children with mitochondrial respiratory chain complex (MRC) defects. Methods: Twenty-two patients with MRC I defect confirmed by biochemical enzyme assays using muscle tissue, were evaluated for renal function with diethylenetriaminepentaacetic acid (DTPA) renal scintigraphy, urine creatinine clearance, serum creatinine (Scr) and cystatin C (Cys C) levels. Results: All patients showed lower levels within normal range of Scr (0.4,0.7 mg/dL, mean 0.47 mg/dL), and with no significant correlation with DTPA,GFR. Cys C showed significant correlation with DTPA,GFR (p < 0.01) providing higher diagnostic accuracy than creatinine in patients with MRC defect. Conclusion: In mitochondrial disorder with MRC defect, Scr could not fully reflect renal function due to the relatively small body mass of patients. Considering the limited clinical availability of DTPA renal scintigraphy, Cys C should be taken as the first step to evaluate GFR in mitochondrial disorders. [source] The use of forearm free fillet flap in traumatic upper extremity amputationsMICROSURGERY, Issue 1 2009Isabel C. Oliveira M.D. Background: Complete traumatic upper extremity avulsions are an infrequent but devastating injury. These injuries are usually the result of massive blunt trauma to the upper limb. Intact issue from amputated or nonsalvageable limbs may be transferred for reconstruction of complex defects resulting from trauma when the indications for replantation are not met. This strategy allows preservation of stump length or coverage of exposed joints, and provides free flap harvest for reconstruction without additional donor-site morbidity. Methods: A retrospective review at São João Hospital was performed on seven patients who had undergone immediate reconstruction with forearm free fillet flaps between 1992 and 2007. Results: There were six men and one woman, with patient age ranging from 17 to 74 years (mean, 41 years). Amputation sites were at the humeral neck (n = 1), at the humeral shaft (n = 5), and below the elbow (n = 1). The area of the forearm free fillet flap skin paddle was 352.14 ± 145.48 cm (mean ± SD). The two major complications were the flap loss and the patient death on postoperative day 3 in other case. The postoperative course in the remaining five cases was uneventful with good healing of the wounds. Minor complications included two small residual defects treated by split-thickness skin grafting and one wound infection requiring drainage and revision. Conclusions: The forearm free fillet flap harvested from the amputated limb provides reliable and robust tissue for reconstruction of large defects of the residual limb without additional donor-site morbidity. Microsurgical free fillet flap transfer to amputation sites is valuable for achieving wound closure, improving stump durability, and maximizing function via preservation of length. © 2008 Wiley-Liss, Inc. Microsurgery, 2009. [source] Free osteocutaneous lateral arm flap: Anatomy and clinical applicationsMICROSURGERY, Issue 2 2003Franz Haas M.D. For many surgeons, the potential to reconstruct skin, fascia, tendon, or bone in a single-stage procedure has made the lateral arm flap the technique of choice for reconstruction of complex defects. The aim of this study was to examine more closely how the humeral bone is supplied by the posterior collateral radial artery. To this end, we dissected 30 cadaver arms to determine the vascular relationship of the lateral arm flap to the humerus. The number of directly supplying vessels, and height to the lateral epicondyle of the humerus, were examined. The reconstructive potential of the osteocutaneous flap in different indications is analyzed in a series of five clinical cases. In all dissected extremities, we found one or two branches of the posterior collateral artery directly and constantly supplying the bone between 2,7 cm proximal to the lateral epicondyle. In five cases, combined defects, including bone, were successfully reconstructed with lateral arm flaps, including vascularized bone. © 2003 Wiley-Liss, Inc. MICROSURGERY 23:87,95 2003 [source] The influence of doping with donor type impurities on the properties of CuInSe2PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 2 2008M. Kauk Abstract The effects of Cl doping on the properties of CuInSe2 monograin powder have been investigated. The capacitance-voltage (C,V) characteristics were measured in the dark at 0.1,100 kHz frequencies and the carrier concentrations were estimated from the slope of C,2 -V plots. The carrier concentration in undoped CuInSe2 was 2 x 1016 cm,3, it increased with increasing the Cl concentration up to 9 x 1016 cm,3. The photoluminescence spectra of undoped and Cl-doped CuInSe2 showed one asymmetrical band originated from the band-tail recombination. The band maximum shifted towards higher energies with increasing Cl concentration but the shape remained the same. We assume that with the incorporation of chloride into the materials the concentration of probably shallower complex defects [VIn + 2ClSe] increases since chloride atoms preferably occupy VSe sites. Therefore the overall acceptor concentration increases slightly. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Formation of complex defects in MncMg1,cO and NicMg1,cO single solid solutionPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 1 2005V. Skvortsova Abstract The results of investigation of the fast neutron irradiation and thermal treatment on absorption spectra of single solid solution of MncMg1,cO, NicMg1,cO and MgO crystals are presented. It is shown that at impurity ion concentration larger than 0.1 mass.% a probability of formation of aggregate centers consisting of more than three F+ - or F-centers is small. After thermal treatment of MncMg1,cO and NicMg1,cO single solid solution irradiated by fast neutrons additional wide bands are observed. We assume that these additional bands belong to complex centers of Mn3+ -VMg and Ni3+ -VMg. The mechanisms of bands formation are discussed. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Use of the Vacuum-Assisted Closure Device in Enhancing Closure of a Massive Skull Defect,THE LARYNGOSCOPE, Issue 6 2004Umesh S. Marathe MD Abstract Objectives/Hypothesis: The objective was to describe a novel technique for reconstructing the cranial vertex without the use of free tissue transfer. Study Design: Case report, literature review, and discussion. Methods: A 50-year-old woman presented from a remote Pacific Island community with a 12 × 14-cm, necrotic, grossly contaminated eccrine gland carcinoma of the cranial vertex that extended through the calvarium but did not invade the dura. Following tumor extirpation, the resulting bony defect was 10 × 12 cm in size, with a concomitant scalp defect of 14 × 16 cm. Free tissue transfer was impossible because of severe intimal peripheral vascular disease, posing a challenging reconstructive dilemma. After tumor resection, the bony edges were covered with local scalp flaps and the vacuum-assisted closure device was placed over the wound at a constant setting of ,50 mm Hg. The vacuum-assisted closure device was changed three times per week for 3 weeks. Results: A thick, 1-cm bed of granulation tissue developed over the dura, allowing temporary coverage by a split-thickness skin graft, and the scalp defect decreased in size by approximately 25%. The patient did not develop meningitis, headache, or localized infection as a result of placement of the vacuum-assisted closure device and tolerated the vacuum-assisted closure well. After a requisite period of healing, tissue expanders and calvarial reconstruction will be performed. Conclusion: Use of the vacuum-assisted closure device is a safe, reliable adjunct in the closure of large cranial defects with exposed dura and offers a novel reconstructive option for complex defects of the head and neck. [source] | |||||||||||||