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Rear Side (rear + side)

Distribution by Scientific Domains
Physics and Astronomy40%

Selected Abstracts

Skin Repair Using a Porcine Collagen I/III Membrane,Vascularization and Epithelization Properties

DERMATOLOGIC SURGERY, Issue 6 2010
FALK WEHRHAN MD
BACKGROUND Collagen membranes have been developed to overcome the problem of limited availability of skin grafts. Vascularization and restricted functional epithelization limit the success of bioartificial constructs. OBJECTIVE To compare the vascularization, epithelization, and integration of a porcine collagen I/III membrane with that of split-thickness skin grafts on skin wounds. MATERIALS AND METHODS In 21 adult pigs, full-thickness skin defects on the rear side of the ear healed by split-thickness skin grafting, by covering with the membrane, or by free granulation. Skin samples on postoperative days 1, 3, 7, 14, 21, and 28 were evaluated histologically (hematoxylin-eosin, Sirius Red) and using immunohistochemistry (cytokeratin 5/6, transforming growth factor beta receptor (TGF,R-III) and immunoblot (TGF,1,3, Smad2/3). Epithelial thickness and TGF,R-III-positive capillary area were quantitatively assessed. RESULTS Epithelization and vascularization in the membrane group were not significantly different from in the group treated with a split-thickness skin graft. Free granulation showed significantly slower epithelization and vascularization (p<.05). TGF,1 and Smad2/3 complex expression were high during free granulation. Matrix was distinguishable until day 7. CONCLUSIONS This membrane serves as a suitable full-thickness dermal substitute, because the membrane is vascularized faster than free granulation tissue and enables early epithelization. Geistlich Biomaterials (Wolhusen, Switzerland) provided the collagen membrane used in this study [source]

Use of METEOSAT water-vapour images for the diagnosis of a vigorous stratospheric intrusion over the central Mediterranean

METEOROLOGICAL APPLICATIONS, Issue 3 2000
K Lagouvardos
The diagnosis of a vigorous dry intrusion over the central Mediterranean is performed using water-vapour images from METEOSAT. This dry intrusion was located on the rear side of a cold front (propagating from Italy to Greece) and played an important role in the onset of thunderstorms over the western Greek coasts. A combination of satellite imagery and potential vorticity analyses showed that the dry air originated in the lower-stratospheric and higher-tropospheric layers. The interaction of the dry air with the moist air masses within the warm conveyor belt ahead of the cold front (overrun of warm air by low equivalent potential temperature air) produced a potentially unstable region over the area of reported thunderstorms. Copyright © 2000 Royal Meteorological Society [source]

Role of a-Si:H bulk in surface passivation of c-Si wafers

PHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 7 2010
A. Illiberi
Abstract The low thermal stability of hydrogenated amorphous silicon (a-Si:H) thin films limits their widespread use for surface passivation of c-Si wafers on the rear side of solar cells. We show that the thermal stability of a-Si:H surface passivation is increased significantly by a hydrogen rich a-Si:H bulk, which acts as a hydrogen reservoir for the a-Si:H/c-Si interface. Based on this mechanism, an excellent lifetime of 5.1 ms (at injection level of 1015 cm,3) is achieved after annealing at 450 °C for 10 min. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Amorphous silicon based p-i-i-n photodetectors for point-of-care testing

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3-4 2010
Marc Sämann
Abstract Modern medical diagnostics demands point-of-care testing (POCT) systems for quick tests in clinical or out-patient environments. This investigation combines the Reflectometric Interference Spectroscopy (RIfS) with thin film technology for a highly sensitive, direct optical and label-free detection of proteins, e.g. inflammation or cardiovascular markers. Amorphous silicon (a-Si) based thin film photodetectors replace the so far needed spectrometer and permit downsizing of the POCT system. Photodetectors with p-i-i-n structure adjust their spectral sensitivity according to the applied read-out voltage. The use of amorphous silicon carbide in the p-type and the first intrinsic layer enhances the sensitivity through very low dark currents of the photodetectors and enables the adjustment of their absorption characteristics. Integrating the thin film photodetectors on the rear side of the RIfS substrate eliminates optical losses and distortions, as compared to the standard RIfS setup. An integrated Application Specific Integrated Circuit (ASIC) chip performs a current-frequency conversion to accurately detect the photocurrent of up to eight parallel photodetector channels. In addition to the optimization of the photo-detectors, this contribution presents first successful direct optical and label-free RIfS measurements of C-reactive protein (CRP) and D-dimer in buffer solution in physiological relevant concentrations. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Autodiffusion: a novel method for emitter formation in crystalline silicon thin-film solar cells

PROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 3 2007
A. Wolf
Abstract The in situ formation of an emitter in monocrystalline silicon thin-film solar cells by solid-state diffusion of dopants from the growth substrate during epitaxy is demonstrated. This approach, that we denote autodiffusion, combines the epitaxy and the diffusion into one single process. Layer-transfer with porous silicon (PSI process) is used to fabricate n-type silicon thin-film solar cells. The cells feature a boron emitter on the cell rear side that is formed by autodiffusion. The sheet resistance of this autodiffused emitter is 330,,/,. An independently confirmed conversion efficiency of (14·5,±,0·4)% with a high short circuit current density of (33·3,±,0·8) mA/cm2 is achieved for a 2,×,2,cm2 large cell with a thickness of (24,±,1) µm. Transferred n-type silicon thin films made from the same run as the cells show effective carrier lifetimes exceeding 13,µs. From these samples a bulk diffusion length L,>,111,µm is deduced. Amorphous silicon is used to passivate the rear surface of these samples after the layer-transfer resulting in a surface recombination velocity lower than 38,cm/s. Copyright © 2006 John Wiley & Sons, Ltd. [source]