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Copyright of Gefaesschirurgie 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.)

Copyright of Gefaesschirurgie 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.)

Background: For the optimal nutrition of children under 2 years of age, it is considered important that they be exclusively breastfed for the first 6 months before being given complementary food. Aims and Objectives: A cross-sectional nutritional baseline survey was undertaken in 2011 in the Kasungu and Mzimba Districts of Malawi to assess the nutritional status of children under 2 years of age and its determinants in order to prepare a nutrition education intervention programme. The intention of this study was to assess the nutritional status of infants aged 0–<6 months with regard to food intake. Methods: Interviews were conducted on randomly selected families with children under 2 years; anthropometric measurements were obtained from mothers and their children. Only infants between 0 and <6 months were selected for analysis (n = 196). An ANCOVA test was performed on age of the infant with mothers' height and weight as covariates. Results: Prevalence of stunting (infants' length-for-age Z-score (LAZ) <−2SD) was 39%, wasting (WLZ <−2SD) 2%, and underweight (WAZ <−2SD) 13%. Of the infants under 6 months, 43% were exclusively breastfed. Predominant breastfeeding and mixed breastfeeding were less common (21% and 36%, respectively). The ANCOVA confirmed the association between exclusive breastfeeding and LAZ and WAZ: exclusively breastfed infants had a higher mean (SE) LAZ (−1·13, 0·12) and WAZ (−0·41, 0·13) than infants not being exclusively breastfed (−1·59, 0·11, and −0·97, 0·11, respectively). There was no overall significant association between breastfeeding practice and WLZ. Conclusion: Exclusive breastfeeding of infants under 6 months is associated with higher mean LAZ and WAZ. Promotion of exclusive breastfeeding in low-income countries is important in preventing growth retardation. [ABSTRACT FROM AUTHOR]

BACKGROUND The quantitative capability of the visual system can be tested using graphic presentations with defined size, form and color. For presentations, a chart projector or monitor can be used. Today, the number of visual function tests on the Internet is increasing constantly. METHODS Options and limitations of visual function tests using the Internet and the authors' own test results are described. RESULTS Several visual function tests, such as visual acuity tests, the Amsler-Grid, stereo and color vision tests, can already be given via Internet. The variability of the tests ranges from the simple presentation of graphic elements to the laboriously programmed interactive input by the user to specify the test result. Under standardized examination conditions, there was a very high correspondence between the results of the authors' own web-based color vision test and those of luminescence color test plates and conventional pigment color plates. CONCLUSIONS However, the interpretation of the test results is difficult due to the absence of controls during the test as well as the heterogeneity of the hardware. In order to obtain comparable test results, differences in size and resolution as well as in brightness, contrast and color of computer monitors must be taken into consideration. Due to the deficits described in the tests, the value of visual function tests on the Internet is rather limited. Currently, the data of test distributers with respect to the test conditions are all still insufficient. Standards need to be defined for Internet-based visual function tests. However, visual function tests on the Internet can achieve test results comparable to those of conventional visual function tests under standardized examination conditions in clinical practice. Further studies are needed to check the accuracy of web-based screening examinations in ophthalmology. [ABSTRACT FROM AUTHOR]

Life tests were performed at room temperature on Si-SiGe HBTs by reverse biasing the base-emitter junction under open collector conditions. The effects on the DC, the low-frequency noise, and the microwave characteristics were investigated both by the analysis of experimental data and by simulations and analytical models. The stress-induced surface damage close to the emitter perimeter was identified to be the degradation mechanism mainly responsible for the variations observed, in all the investigated parameters [ABSTRACT FROM PUBLISHER]

Under physiological conditions, the pressure in the central retinal vein is equal to or higher than the intracranial pressure (ICP) because the cerebrospinal fluid (CSF) passes the sheath of the optic nerve before draining into the cavernous sinus. The optic nerve sheath is where the ICP affects the retinal venous pressure. Ophthalmodynamometry (ODM) is a useful method for determining the central retinal artery pressure. While papilledema and a lack of venous pulsations are commonly used as a vague indication of the ICP, ODM may be advantageous for determining the pressure in the central retinal vein. Until now, however, the venous pressure has never been compared with the intracranial pressure. In the present study, the pressure in the central retinal vein was recorded in 31 patients while the ICP was simultaneously being recorded for various reasons. The results demonstrate a linear correlation (r = 0.968) between the pressure in the central retinal vein and the ICP. This correlation is of great practical value since until now, reliable intracranial pressure monitoring has only been possible by invasive means, by placing a probe either in the brain parenchyma or the ventricle. Ophthalmodynamometry is useful for momentary assessment of the ICP, can easily be repeated, and may be used whenever an elevated ICP is suspected in hydrocephalus, brain tumors and after head injury. However, it is not suitable for continuous ICP monitoring. [ABSTRACT FROM AUTHOR]

This work for the first time experimentally investigates the hot carrier effects on the RF characteristics (up to 30 GHz) of Si/SiGe heterojunction bipolar transistors (HBT's). Reverse base-emitter voltage stresses were applied at room temperature on BiCMOS compatible, sub-micron transistors. The main observed degradation is a decrease of S 21. It was found that this degradation is minimized (maximized) when biasing at constant collector (base) current. These results may be valuable indications also for degradations induced by ionizing radiations [ABSTRACT FROM PUBLISHER]

A mechanism of strain relief of H[sup +] ion implanted and annealed pseudomorphic Si[sub 1-x]Ge[sub x]/Si(100) heterostructures grown by molecular beam epitaxy is proposed and analyzed. Complete strain relaxation was obtained at temperatures as low as 800 °C and the samples appeared free of threading dislocations within the SiGe layer to the limit of transmission electron microscopy analysis. In our model, H filled nanocracks are assumed to generate dislocation loops, which glide to the interface where they form strain relieving misfit segments. On the basis of this assumption, the conditions for efficient strain relaxation are discussed. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]