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Notes: Lateral patterning of highly doped silicon-on-insulator films allows us to observe conductance oscillations due to single-electron charging effects. In our devices, silicon nanostructures are embedded into a metal–oxide–silicon configuration. The single-electron effects can be tuned both by an in-plane sidegate, as well as by a metallic topgate, a technology which is compatible with large-scale integration of single-electron devices with dimensions down to 10 nm. We compare the influence of different gating electrodes, important for ultralarge scale integration, on the electron islands. © 2001 American Institute of Physics.

Notes: Surgical researchers were among the first to describe the different phases of wound healing and the events in tissue repair and regeneration that were taking place during each phase. The understanding of these events has been significantly enhanced in recent years by modern techniques in molecular and cellular biology. In this article, we discuss new findings in scarless fetal repair, angiogenesis in wound healing, and keloid pathogenesis. This serves to highlight the advances that have been made and also how much remains to be understood. (WOUND REP REG 2003;11:411–418)

Notes: To elucidate the role for transforming growth factor-β isoforms (β1, -β2, and -β3) in wound repair, we used isoform-specific antibodies to detect the spatial and temporal expression of the latent and mature/active transforming growth factor-β isoforms by immunohistochemical localization through 21 days after excisional and incisional wounding of ovine skin. Although incisional and excisional wounds showed similar patterns of transforming growth factor-β immunoreactivity, we found a differential temporal and spatial expression of the latent and mature transforming growth factor-β isoforms throughout wound repair. Specifically, 1 day after wounding, there was a marked increase in transforming growth factor-β isoforms in the epithelium adjacent to the wound, epidermal appendages, and the cells and matrix of the granulation tissue. At this time, transforming growth factor-β3 isoform was the most abundant. Most notably, the epidermis adjacent to the wound was intensely immunoreactive for all transforming growth factor-β isoforms 1 day after injury. However, the migrating epithelium, derived from both the hair follicles and the wound margins, was completely devoid of immunoreactive transforming growth factor-β until reepithelialization was complete. Within the inflammatory exudate, there was a distinct band of leukocytes that was immunoreactive for transforming growth factor-β2 and -β3 1 day after injury and 1 day later for transforming growth factor-β1. Although transforming growth factor-β1 and -β2, latent transforming growth factor-β2, transforming growth factor-β3, and latent transforming growth factor-β3 immunostaining was present in the numerous fibroblasts and other dermal cells, latent transforming growth factor-β1 was only associated with the extracellular matrix. In general, immunoreactivity remained high until day 7 after wounding and slowly subsided over time. However, by day 21, immunostaining had not returned to normal and the original wound was replete with immunoreactive fibroblasts and a dense, immunostained extracellular matrix. Thus, although the dynamic presence of transforming growth factor-β isoforms exemplifies its positive role in the wound repair process, its persistence together with its known potent effects on matrix accumulation, supports its role in scar formation.

Notes: We define superconducting constrictions by ploughing a deposited Aluminum film with a scanning probe microscope. The microscope tip is modified by electron-beam deposition to form a nanoplough of diamond-like hardness which allows the definition of highly transparent Josephson junctions. Additionally, a dc superconducting quantum interference device is fabricated in order to verify the junction's behavior. The devices are easily integrated in mesoscopic devices as local radiation sources and can be used as tunable on-chip millimeter-wave sources. © 1998 American Institute of Physics.

Notes: X-ray diffraction measurements in the region of small incidence and exit angles on thin amorphous silicon/germanium films on laterally structured surfaces are performed. From fits of the data we obtain directly how the Fourier components of the substrates propagate through the evaporated films without being influenced by the intrinsic statistical roughness of the interfaces. The results show that a replication factor extracted from a given model can be quantitatively tested with our measurements. © 1996 American Institute of Physics.

Notes: Single-electron transistors utilizing Coulomb blockade effects are promising candidates for future silicon based nanoelectronics. We present the fabrication of such transistors and measurements that reveal Coulomb blockade behavior. Various silicon quantum dots are investigated up to room temperature. We employ a dual gate configuration with which we are able to control our devices by both a metallic top gate as well as by an in-plane gate. This design principle enhances the integration density. © 2001 American Institute of Physics.

Notes: Magnetotransport of high-mobility electrons in quasi-one-dimensional quantum wires in Si/Si0.7Ge0.3 heterostructures is studied. Arrays of shallow and deep etched wires with a period of 480 nm are defined by laser holography and patterned by reactive ion etching. Typical features of transport in narrow electron channels, such as oscillations due to the depopulation of quasi-one-dimensional subbands and an anomalous resistance maximum at low magnetic fields are observed. The narrowest channels have an effective width of ≈70 nm and a sublevel spacing of 1 meV. © 1995 American Institute of Physics.

Notes: We use an atomic force microscope operating in a dynamic modus, commonly called tapping mode, to completely oxidise through thin 5 nm titanium films using the very local electric field between the tip and the sample. Tapping mode local oxidation minimizes tip degradation and therefore enhances resolution and reliability. By working under a controllable environment and measuring the resistance in situ while oxidising we are able to fabricate well-defined isolating Ti–TiOx–Ti barriers as small as 15 nm. Their conductance shows an exponential dependence on the oxide width, thereby identifying tunneling as the dominant conduction mechanism. From the nonlinear current-voltage characteristic a tunneling barrier height of 178 meV is derived. © 1997 American Institute of Physics.

Notes: We employ an atomic force microscope to directly pattern the electron system of InAs–AlSb surface quantum wells. Sharp and sturdy electron beam deposited tips are developed to withstand the comparatively high ((approximate)μN) forces in the direct patterning process. By direct patterning the InAs surface quantum well we modulate the electron system without any mask. We are therefore able to directly transfer the excellent lithographic resolution of atomic force microscopy to an electron system. The magnetoresistance of such fabricated antidot arrays is discussed. © 1998 American Institute of Physics.

Notes: We employ the vibrating tip of an atomic force microscope as a lithographic tool to mechanically pattern a thin photoresist layer covering a GaAs–AlGaAs heterostructure. High aspect ratio electron beam deposited tips, additionally sharpened in an oxygen plasma, are used to minimize the dimensions of the fabricated quantum electronic devices. The fabrication parameters of the tips and the sharpening process are investigated. With these ultrasharp tips we are able to produce lines and holes with periods down to 9 nm in photoresist. In addition, the very sharp tips yield substantial improvements in the imaging mode. © 1995 American Institute of Physics.