High-resolution phonon study of the Ag(100) surface.

Using high-resolution electron energy loss spectroscopy the phonon dispersion of Ag(100) has been studied at two different sample temperatures of 86 and 300 K. The dominant feature in the spectra corresponds to the Rayleigh wave. Its full dispersion is determined along the ΓX high symmetry direction in the first and second Brillouin zones. The Rayleigh phonon maximum at the X point shows a redshift with increasing temperature. This is explained based on a surface anharmonicity with an anharmonicity constant of 0.014, comparable to the value reported for Cu(100). In the vicinity of the Γ point two additional phonon features have been discovered at about 110 and 160 cm(-1), which are tentatively assigned to high density of states features from the bulk phonon bands. However, the observed steep dispersion is in contrast to theoretical calculations. Along ΓX two surface resonance branches have been observed with maximum frequencies in the range of 90-110 cm(-1) near to the zone boundary. These branches agree with helium atom scattering data where available, but are not predicted by theory.

The use of clinical CCT images in the forensic examination of closed head injuries.

The forensic evaluation of clinical cranial computed tomographies (CCT) frequently is the only reliable source of morphological evidence in head injuries when the injured individual survives or when death is delayed and autopsy findings are characterized by secondary changes. We have reviewed 21 cases where clinical CCT examinations were used to establish a medico-legal diagnosis. In 18 cases falls (n = 13) could be distinguished from blows (n = 5) due to the presence and/or absence of coup and contrecoup lesions and linear or depressed skull fractures. In two cases the striking object could be identified by digital superimposition. The minimum number of blows could be determined in 1 case. Only in 3 remaining cases the results were inconclusive. In our experience, CCT scans provide an important source of information for the forensic expert. To have unbiased access to these information, it is useful to evaluate the CT scans personally which requires a basic knowledge of traumatic changes found on radiographs.

[Effect of graduated vitamin D3 doses and different ration composition on the 25OH-vitamin D3 plasma concentration and fattening and slaughter production of bulls]. / Einfluss gestaffelter Vitamin-D3-Gaben und unterschiedlicher Rationsgestaltung auf die 25OH-Vitamin-D3-Plasma-Konzentration sowie Mast- und Schlachtleistung von Mastbullen.

In a individual feeding experiment (348 days) 24 fattening bulls were given either a ration high in roughage (2.8 kg concentrate mixture, wheat straw ad libitum: group I) or high in concentrate (5.6 kg concentrate mixture, wheat straw ad libitum group II) supplemented with various levels of vitamin D3 (0, 250, 500, 1,000, 2,000, 4,000 and 8,000 IU per 100 kg body weight (bw) and day) and minerals as required. After 58, 101, 134, 172, 205, 277 and 340 days 25-OH-D3 plasma concentration was estimated. Fattening and slaughtering parameters were measured. The 25OH-D3 plasma concentration was significantly influenced by vitamin D3 supply, kind of ration and day of taking samples. 25-OH-D3 plasma concentration decreased below 5 ng per ml when vitamin D3 supply was less than or equal to 250 IU per 100 kg bw and day. The initial plasma levels were maintained when 500 IU vitamin D3 per 100 kg bw and day was given (6.6 ng per ml). Administration of greater than or equal to 1,000 IU per 100 kg bw and day increased 25OH-D3 plasma level (greater than 10 ng/ml). Plasma 25OH-D3 concentration was significant higher when bulls consumed diets rich in concentrate (10.6 and 18.2 ng/ml for I and II after 340th day). Differences in content of cell walls and crude fat of rations may be responsible for results. Daily weight gain of bulls amounted to 712 and 945 g when fed diets I or II. Dry matter intake and live weight gain were not significantly influenced by different vitamin D3 supply. Clinical symptoms of rachitis did not appear.