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The apertureless scanning near-field microscope (ASNOM) mapping of surface phonon polariton (SPP) waves being excited at the surface of the SiC polar crystal at a frequency corresponding to the lattice resonance was investigated. The wave with well-defined direction and source position, as well as a well-known propagation law, was used to calibrate the signal of an ASNOM. An experimental proof is presented showing that the signal collected by the ASNOM in such a case is proportional (as a complex number) to the local field amplitude above the surface, regardless of the tip response model. It is shown that the expression describing an ASNOM response, which is, in general case, rather complicated nonlinear function of a surface/tip dielectric constants, wavelength, tip vibration amplitude, tip shape etc., can be dramatically simplified in the case of the SPP waves mapping in a mid-IR range, due to a lucky combination of the tip and surface parameters for the case being considered. A tip vibration amplitude is much less than a running SPP wave field decay height in a normal direction. At the same time, the tip amplitude is larger than a characteristic distance at which a tip-surface electromagnetic near-field interaction plays a significant role. [ABSTRACT FROM AUTHOR]

Today an increasing number of patients seek aesthetic improvement through minimally invasive procedures, and interest in soft tissue augmentation and filling agents is rising steadily. However, a thorough understanding of these substances, their indications and contraindications, as well as a profound knowledge of different implantation techniques is essential to provide an aesthetically pleasing result for the patient. This presentation gives an overview of the current injectable biomaterials, their major indications, advantages and disadvantages, with focus on collagen, hyaluronic acid, poly- l-lactide, and autologous fat grafting. [ABSTRACT FROM AUTHOR]

During 30 months, 40 “septum-based” mammaplasties with a craniomedial pedicle were performed. This report aims to demonstrate the anatomic basics of the horizontal septum and the authors’ experience with the septum-based mammaplasty technique. A series of 40 consecutive patients underwent a “septum-based” mammaplasty. This technique uses a medial pedicle based on Würinger`s horizontal septum, which is the main plain for the neural and vascular supply of the nipple–areolar complex (NAC). The mean nipple-to-sternal-notch distance was 32 cm (range, 24–43 cm). The mean resection weight was 648 g (range, 484–1,320 g), and the mean nipple elevation was 9.5 cm (range, 5–18 cm). There were no hematomas and no partial or complete NAC necroses. Minimal wound dehiscence at the T-junction was present in three cases (7.5%). The pre- and postoperative NAC sensibilities were comparable in all the patients. Based on Würinger`s horizontal septum, a safe and well-vascularized mammaplasty is possible even with large resection weights and long nipple–areola distances, and NAC sensibility can be preserved. The reported technique combining excellent pedicle perfusion with a wide variety of breast shaping proved to be safe. [ABSTRACT FROM AUTHOR]

A novel average inductor current sensing circuit integrable in CMOS technologies is presented. It is designed for DC-DC converters using buck, boost, or buck-boost topologies and operating in continuous conduction mode at high switching frequencies. The average inductor current value is used by the DC-DC controllers to increase the light load power conversion efficiency (e.g., selection of the modulation mode, selection of the dynamic width of the transistors). It can also be used to perform the constant current charging phase when charging lithium-ion batteries, or to simply detect overcurrent faults. The proposed average inductor current sensing method is based on the loss-less sensing MOSFET principle widely used in monolithic CMOS integrated DC-DC converters for measuring the current flowing through the power switches. It consists of taking a sample of the current flowing through the power switches at a specific point in time during each energizing and de-energizing cycle of the inductor. By controlling precisely the point in time at which this sample is taken, the average inductor current value can be sensed directly. The circuit simulations were done with the Cadence Spectre simulator. The improvements compared to the basic sensing MOSFET principle are a lower power consumption because no high bandwidth amplifier is required, and less noise emission because the sensing MOSFET is no more switched. Additionally, the novel average inductor current sensing circuit overcomes the low bandwidth limitation previously associated with the sensing MOSFET principle, thus enabling it to be used in DC-DC converters operating at switching frequencies up to 10 MHz and above. [ABSTRACT FROM AUTHOR]

Gynecomastia is a potential side effect of hormone therapy for prostate cancer. In large, randomized, placebo controlled studies approximately 50% or more of patients with prostate cancer experienced gynecomastia attributable to various mechanisms. Although it is mostly reported as mild to moderate, gynecomastia is one of the reasons most frequently cited for premature discontinuation of such treatment. Prophylactic radiotherapy and prophylactic tamoxifen have been shown to decrease the incidence of hormone-induced gynecomastia; nevertheless, there are still cases of refractory gynecomastia, and in these plastic surgery is needed for correction. Gynecomastia is a benign enlargement of the male breast, requiring no treatment unless it is a source of embarrassment and/or distress for the adolescent or man affected. The indications for surgical treatment of gynecomastia are founded on two main objectives: restoration of the male chest shape and diagnostic evaluation of suspected breast lesions. The authors believe that the complete circumareolar technique with no further scarring creates the best aesthetic results with fewer complications. When this is used in combination with liposuction very pleasing aesthetic results can be achieved. [ABSTRACT FROM AUTHOR]

Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Necrotizing soft-tissue infections such as necrotizing fasciitis continue to have a high morbidity and mortality. More and more, these difficult cases are being referred to burn centers for specialized wound and critical care treatment. The case of a necrotizing soft-tissue infection after a honeybee sting is reported. To the best of our knowledge, it is the first documented case of necrotizing fasciitis caused by invasive group A Streptococcus from a bee sting. A 56-year-old man was stung by a bee in the left upper gluteal region. The sting was removed by the patient. Within hours, erythema, swelling, itching, and pain developed. On day 7, after the bee sting, the patient was admitted to a general surgery department with progressive skin and soft-tissue necrosis around the hip and the upper left leg. Because of the rapidly deteriorating condition, the patient was referred to our burn ICU with the picture of a progressive necrotizing fasciitis. The skin necrosis required immediate epifascial necrectomy. Additionally local therapy with topical antiseptics was performed. The surface was temporarily covered with xenograft, definitive coverage was achieved with autologuous skin graft transplantation. Advancements in wound care and critical care, which have become standard in the treatment protocols of patients with necrotizing soft-tissue infections, have markedly improved the prognosis. However, these infections continue to be a source of high morbidity and mortality and significant healthcare resource consumption. These challenging patients are best served with prompt diagnosis, immediate radical surgical debridement, and aggressive critical care management. Referral to a burn center may help to provide best possible surgical intervention, wound care, and critical care management. [ABSTRACT FROM AUTHOR]

Focused ion beams with diameters of 8 to 50 nm are used for material processing in the nanoscale regime. In this paper, effects of the ion beam–solid interaction determining the formation of small structures by ion-beam sputtering and chemically assisted material deposition and etching are investigated. In the case of decreasing feature size, angle-dependent sputtering, a non-constant sputter rate, and scattered ions play an important role. The impact on side-wall angle, aspect ratio, and shape of the bottom of the etched structures is discussed. In beam tail regions, these effects will be especially pronounced, leading to material swelling instead of material removal. Ion beam assisted etching and deposition will face additional effects. For small structures, gas depletion becomes a significant drawback. The impact on gas depletion and the competition with sputtering are discussed. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) was irradiated with 10 and 63 keV Ar+ ions to fluences of 1 × 1017 to 3 × 1019 m−2 and then it was grafted with aminoacid (alanine). The changes of surface polarity, electrical conductivity, and oxygen concentration were examined on pristine, as-irradiated, and irradiated-grafted PE. The in vitro adhesion of mice fibroblasts on the modified PE was evaluated 24 hours after inoculation. It was proved that for the PE irradiated at 10 keV ion energy, the presence of chemically bound alanine increases cell adhesion and its homogenity. For PE irradiated with 63 keV ions, however, the alanine grafting leads to a reduction of the number of adhering cells. It was found that a rising surface polarity increases cell adhesion, but when its value is too high the cell adhesion starts to decrease. No correlation between electrical conductivity and cell adhesion was observed. In general, higher cell adhesion is observed on modified PE in comparison with pristine one. [ABSTRACT FROM AUTHOR]

Tissue changes in ischaemic stroke are detectable by diffusion-weighted MRI (DWI) within minutes of the onset of symptoms. However, in daily routine CT is still the preferred imaging modality for patients with acute stroke. Our purpose of this study was to determine how early and reliably ischaemic brain infarcts can be identified by CT and DWI. Three neuroradiologists, blinded to clinical signs but aware that they were dealing with stroke, analysed the CT and DWI of 31 patients with an acute ischaemic stroke. We calculated k-values to analyse inter-rater variability. The ratings were compared with follow-up studies showing the extent of the infarct. The combined assessment of all observers gave positive findings in 77.4 % of all CT examinations, with k = 0.58. Areas of high signal were seen on all DWI studies by all observers (k = 1). Estimation of the extent of the infarct based on DWI yielded k = 0.70 and that based on CT k = 0.39. DWI was much more reliable than CT in the detection of early ischaemic lesions and we believe that it should be used in acute ischaemic stroke before aggressive therapeutic intervention. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) foils were modified by irradiation with Ar E+ and Xe E+ ions to different fluences and different physico-chemical properties of the irradiated PE were studied in relation to adhesion and proliferation of keratinocytes on the modified surface. Changes in the PE surface roughness were examined using the AFM technique, the production of conjugated double bonds and oxidized structures by UV-VIS and FTIR techniques respectively. The surface polarity was determined by measuring surface contact angle and two-point technique was used for the determination of PE sheet resistance. Adhesion and proliferation of keratinocytes was characterized using the MTT-test. The ion irradiation leads to creation of conjugated double bonds which, together with progressive carbonization, contribute to the observed decrease of sheet resistance. Oxidation of the irradiated PE surface layer during the ion implantation is observed. Besides oxidation, the PE surface polarity is affected by other factors. The observed increase of the PE surface roughness due to the ion irradiation is inversely proportional to the ion size. The adhesion and proliferation of keratinocytes on the ion irradiated PE is significantly higher than on the pristine PE. Distribution of results in keratinocyte cultivation and the number of cells is related to the ion fluence applied and to ion species as well. [ABSTRACT FROM AUTHOR]

A Q-switched Nd: YAG laser with a pulse duration of 20 ns was used to investigate effects of laser annealing in gallium implanted silicon. Rutherford backscattering and Hall-effect measurements were performed to evaluate the annealed layer. Differential Hall-effect measurements were carried out to obtain carrier concentration profiles after annealing. It was found that a maximum sheet carrier concentration of 8×10 cm can be obtained for a gallium implantation of 10 cm by laser annealing with an energy density of more than 1.0 J cm. Although the peak carrier concentration was found to be 8.0×10 cm, the annealed layer showed polycrystalline structures even after annealing with an energy density up to 4J cm. The annealing took place in the solid phase in this energy density range. [ABSTRACT FROM AUTHOR]

The diffusion behavior of implanted arsenic in polycrystalline silicon was investigated, using backscattering and electrical measurements. The diffusion coefficient is D=8.5×10 exp (−2.74/kT) for polycrystalline silicon deposited on freshly-etched silicon and D=1.66 exp (−3.22/kT) for the deposition on silicon having natural oxide. At the interface to the single-crystalline silicon, a pile-up of arsenic occurs, which depends also on the surface treatment prior to the deposition of the polycrystalline silicon. [ABSTRACT FROM AUTHOR]

Minority carrier lifetimes in nitrogen implanted GaAsP ( x=0.4; 0.65) were measured at 77K by an optical phase shift method as a function of nitrogen dose and annealing temperature in order to investigate the dependence of the lifetime on the concentration of nitrogen isoelectronic traps. A large increase in the lifetime was observed after nitrogen implantation followed by annealing at and above 800°C. The maximum lifetimes were 22ns for GaAsP and 6.7 ns for GaAsP. They were obtained by implantation to a dose of 5×10 cm in GaAsP and 10 cm in GaAsP. The lifetime after nitrogen implantation followed by annealing was longer by a factor of 6-7 than that of the unimplanted sample. [ABSTRACT FROM AUTHOR]

The range parameters of boron in silicon have been measured using theB( n,α) Li-nuclear reaction. The results indicate that the distributions can be perfectly modeled using Pearson IV distributions with 4 moments. The range is very well described by theoretical calculations, whereas the higher moments show a strong deviation from theory. [ABSTRACT FROM AUTHOR]

The annealing behavior of arsenic-implanted silicon under scanned cw CO-laser irradiation from front and back surfaces is investigated. Ellipsometry, Hall effect, Rutherford backscattering measurements and neutron activation analysis indicate an enhancement of annealing efficiency by laser irradiation from the back surface, which provides complete recovery of crystal damage, high substitutionality and electrical activation of implanted arsenic atoms without redistribution of concentration profile. The enhancement of annealing efficiency under back-surface irradiation is explained by the difference in laser reflection from the front and back surface of silicon wafers. No differences in the results are found for scanned and static annealing. [ABSTRACT FROM AUTHOR]

The implantation of nitrogen into silicon to produce SiN layers was investigated to find an alternative to CVD-SiN layers used in ISOPLANAR-and LOCOS-technology. The technological properties of the implanted SiN layers in respect to oxidation inhibition and etching are comparable or superior to CVD-SiN layers. The implanted layers are more resistent against oxidation for nitrogen doses of 2.4×10 cm at 30keV. The etching behavior is comparable for both types of SiN-layers. In the implanted layers no pinholes are found and threre is no formation of a bird's beak, as is well known in the case of CVD-nitride. [ABSTRACT FROM AUTHOR]

CW CO-laser annealing of arsenic implanted silicon was investigated in comparison with thermal annealing. Ion channeling, ellipsometry, and Hall effect measurements were performed to characterize the annealed layers and a correlation among the different methods was made. The laser annealing was done with power densities of 100 to 640 W cm for 1 to 20 s. It was found that the lattice disorder produced during implantation can be completely annealed out by laser annealing with a power density of 500 W cm and the arsenic atoms are brought on lattice sites up to 96±2%. The maximum sheet carrier concentration of 6×10 cm was obtained for 1×10 cm implantation after laser annealing, which was up to 33% higher than that after thermal annealing at 600 to 900°C for 30 min. [ABSTRACT FROM AUTHOR]

The diffusion behaviour of implanted boron in silicon was investigated using theB( n,α) Li nuclear reaction. An anomalous behavior with a strong reduction of the diffusivity above an effective solubility limit at 1.5×10, 6×10, and 1.1×10 cm was found for annealing temperatures of 800, 900, and 1,000°C, respectively. [ABSTRACT FROM AUTHOR]

Nitrogen ions were implanted in GaAsP (x=0.4; 0.65) at room temperature at various doses from 5×10 cm to 5×10 cm and annealed at temperatures from 600°C up to 950°C using a sputtered SiO encapsulation to investigate the possibility of creating isoelectronic traps by ion implantation. Photoluminescence and channeling measurements were performed to characterize implanted layers. The effects of damage induced by optically inactive neon ion implantation on photoluminescence spectrum were also investigated. By channeling measurements it was found that damage induced by nitrogen implantation is removed by annealing at 800°C. A nitrogen induced emission intensity comparable to the intensity of band gap emission for unimplanted material was observed for implanted GaAsP after annealing at 850°C, while an enhancement of the emission intensity by a factor of 180 as compared with an unimplanted material was observed for implanted GaAsP after annealing at 950°C. An anomalous diffusion of nitrogen atoms was found for implanted GaAsP after annealing at and above 900°C. [ABSTRACT FROM AUTHOR]

The activation energy for the annealing of arsenic implanted layers in silicon was studied by isothermal and isochronal annealing experiments. Different mechanisms are responsible for the annealing behavior. At low doses and at temperatures below 700°C a doubly charged complex is formed with an activation energy of 0.86 eV which dissociates at higher temperatures with an activation energy of 3.58 eV. At high doses which result in the formation of an amorphous layer a single activation energy of 2.75 eV is measured. [ABSTRACT FROM AUTHOR]

Measurements of doping concentration and mobility of arsenic implanted silicon at high energies and at low energies with following drive-in diffusion are presented. The electrical measurements are compared with and supported by backscattering measurements. Tails which are present after short time anneals vanish during drive-in diffusion. A temperature of at least 825°C is required to fully activate the arsenic and to obtain the same mobility as in diffused samples. Backscattering data reveal an anomaly in the annealing behavior of the damage. After prolonged annealing As shows some accumulation at the surface. For drive-in diffusions lattice location experiments were performed. [ABSTRACT FROM AUTHOR]

The important role of damage dependent electrical activation in the case of boron implanted silicon layers is whown by comparing measured acceptor concentration profiles in differently amorphized silicon layers. It is shown that the amorphous layer is completely recrystallized after a 650° C anneal for 10 min and the implanted boron is electrically active. In the heavily damaged but not amorphous region underneath the amorphous layer the implanted boron is hardly electrically active after this temperature treatment. At higher annealing temperatures the electrical activity increases, but 900° C are required for complete activation of the implanted boron. These results indicate that the process to activate the implanted boron electrically is strongly damage dependent. We thus found a new contribution to the understanding of the annealing behavior of implanted layers. [ABSTRACT FROM AUTHOR]

The minimum channel length of a MOS transistor which can be achieved while keeping the fluctuations of the threshold voltage caused by random fluctuations of dopant atoms in the depletion layer within a tolerable range is examined. As the basis of all calculations, the Poisson distribution which is used to describe the number of dopant atoms in the depletion layer is combined with an analytical model for the threshold voltage of a short-channel transistor. The influence of major technological parameters on the minimum channel length is presented in detail by fitting a polynomial equation to the calculated data. [ABSTRACT FROM AUTHOR]

The influence of ion-beam mixing on ultra-thin cobalt silicide (CoSi) formation was investigated by characterizing the ion-beam mixed and unmixed CoSi films. A Ge ion-implantation through the Co film prior to silicidation causes an interface mixing of the cobalt film with the silicon substrate and results in improved silicide-to-silicon interface roughness. Rapid thermal annealing was used to form Ge ion mixed and unmixed thin CoSi layer from 10 nm sputter deposited Co film. The silicide films were characterized by secondary neutral mass spectroscopy, x-ray diffraction, tunneling electron microscopy (TEM), Rutherford backscattering, and sheet resistance measurements. The experi-mental results indicate that the final rapid thermal annealing temperature should not exceed 800°C for thin (<50 nm) CoSi preparation. A comparison of the plan-view and cross-section TEM micrographs of the ion-beam mixed and unmixed CoSi films reveals that Ge ion mixing (45 keV, 1 × 10 cm) produces homogeneous silicide with smooth silicide-to-silicon interface. [ABSTRACT FROM AUTHOR]

Copyright of Theoretical & Applied Climatology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)