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Regarding the ever increasing demand for net shaping, research on innovative technologies on tool material and design becomes an important factor for the overall efficiency and competitiveness. The tools in cold forging have to withstand damaging mechanisms of both fatigue and wear, which may act concurrently at different locations on the tool surface. Therefore, process specific tool material selection and local surface treatment of the tools already at the design stage becomes crucial. In this respect, industrial ceramics, offering a better solution against conventional tool steels in terms of wear resistance, occupies the first part of the research presented in this paper. A ceramic adapted tool design with the consideration of thermal effects has been given. Whereas, the second part of the research deals with the locally optimised surfaces of steel tools in terms of fatigue and wear resistance. Three different surface treatment methods are applied on cold forging tools and the results on tool life have been given.

Zusammenfassung:Eine Apraxie ist häufig Folge einer linkshemisphärischen Hirnschädigung oder einer Demenz. Die zuverlässige Diagnose einer Apraxie ist u. a. als Voraussetzung für eine effektive Therapie der Störung erforderlich. Der Berliner-Apraxie-Test (BAXT) wurde für die Diagnose einer buccofacialen, einer ideomotorischen Gliedmaßenapraxie und einer ideatorischen Apraxie konstruiert. Ziel der vorgestellten Arbeit war die Identifikation valider und reliabler Items für den BAXT. In einer Gruppe von 60 Schlaganfallpatienten für die ideomotorischen Aufgaben (Studie 1) und 12 Patienten mit Alzheimer-Erkrankung für die ideatorischen Aufgaben (Studie 2) wurde die Kennwerte (Inter-Rater-Reliabilität, Schwierigkeit, Trennschärfe und Kriteriumsvalidität) der Aufgaben bestimmt. Die Anordnung der selektierten Testaufgaben erfolgte in aufsteigender Schwierigkeit unter Berücksichtigung einer möglichst geringer Interkorrelation der Items. Die Ergebnisse deuten auf eine ausreichende Itemgüte (N= 44) der Testendform des BAXT zur Erfassung ideomotorisch-apraktischer Phänomene bei Schlaganfallpatienten hin. Ersten Analysen in einer Population von 12 Patienten mit Alzheimer-Erkrankung ergaben Hinweise dass die Diagnose einer ideatorischen Apraxie basierend auf den 10 ausgewählten Testaufgaben möglich ist.

In bulk metal forming the tribological state is significantly dependent on the surface topography of tool and workpiece. To provide the process with an improved tribological behaviour in some cases the billet's surface is prepared by shot blasting. Micro texturing of the tool surface provides an additional opportunity to optimise the frictional conditions.

In order to investigate evaporation and desolvation capacities of the enclosed inductively coupled plasma discharge, rotational temperatures (which are commonly considered a good approximation of the heavy particle temperature or gas temperature) were determined as a function of their spatial distribution and their dependence on physical parameters such as gas flows (80–740 mL/min), moisture load, etc. The procedure utilizes the fine structure of the (A2Σ+→ X2Πi) OH band having its band head at 306.4 nm. The rotational temperatures were obtained from the slopes of their Boltzmann plots. Spatial resolution and simultaneous line detection was possible by using a charge-coupled device (CCD) camera in the focal plane of the removed exit slit of a Czerny–Turner monochromator. An interactive data language (IDL) program was developed to calculate the temperature distribution from the received CCD images. Results of the measurement show that the rotational temperatures are between 3750 and 4350 K. They further show the M-shaped spatial profile of analyte intensities and temperature. In the examined gas flow range (80–740 mL/min) the dependence on absolute gas flows and moisture load (5 mg/L) is negligible.

Microforming is a well suited technology to manufacture very small metallic parts, in particular for mass production, as they are required in many industrial products resulting from microtechnology. Compared to other manufacturing technologies microforming features specific economical and ecological advantages. Nevertheless, there are only some singular applications known until today. This paper tries to find out the reason why, analyzing systematically the problems emerging in transferring the know-how on forming from the macro- to the microworld. Reviewing the state of the art in basic and applied research reveals that scaling effects do appear not only within the process but must be taken into account in all the other areas of the whole forming system as well, demanding finally new solutions especially for tool manufacturing and machine concepts. Recent progress, innovative ideas and new developments on these sectors represent a promising basis to exploit the inherent potential of microforming in the future.

Karyotyping of a malformed male newborn revealed the unbalanced karyotype of 46,XY, psudic(5;21)(q12;p13), +5 resulting in trisomy for the short arm of chromosome 5 and partial trisomy for 5q. Both parents had normal karyotypes in their peripheral blood lymphocytes. A second pregnancy ended in a miscarriage at 16 weeks gestation, sonographically 12 weeks. Karyotyping of chorionic villi from the abortus revealed the same unbalanced karyotype that had been identified in the first child. Fluorescence in-situ hybridization analysis confirmed a trisomy 5p. Microsatellite marker analysis ruled out illegitimacy and proved the maternal origin of the trisomic section of chromosome 5. Extended chromosome analysis of 60 metaphase cells from maternal skin fibroblasts and 40 metaphase cells from lymphocytes did not reveal mosaicism for psudic(5;21). These findings suggest the presence of a maternal germline mosaicism.

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Abstract: Pineal lesions are rare. Tumours in this location comprise 0.4–1 % of intracranial tumours. They grow mainly as solid-mass lesions, and cystic tumours are not common. On MRI, a cystic configuration is associated usually with non-neoplastic pineal lesions rather than with a tumour, but analysis does not allow cystic pineal tumours to be distinguished from glial cysts with certainty. We compared neuroradiological and pathological data from 13 cystic pineal lesions, analysing preoperative MRI. Formalin-fixed, paraffin-embedded surgical specimens were stained routinely and immunocytochemically, using the streptavidin-biotin-complex method. Histology revealed six pineocytomas, four glial cysts, an arachnoid cyst, a low-grade astrocytoma and a teratoma. Signal characteristics of pineocytomas were similar in many respects to those of glial pineal cysts. Histomorphological analysis allowed unambiguous discrimination between pineocytomas and glial pineal cysts.

To review the direct DNA testing for Huntington's disease (HD) in Germany, Switzerland, and Austria from 1993 to 1997, and to analyze the population with regard to age structure, gender, and family history.

In a blinded, randomized design, six histopathologists with an interest in gynecological pathology examined the inter- and intraobserver variation of the histopathological diagnosis of endometrial hyperplasia according to the World Health Organization (WHO) classification of 1975 and the new WHO classification of 1994. On four occasions, the pathologists assessed hematoxylin/eosin-stained slides from 128 cases originally diagnosed and coded in the Snomed system as endometrial hyperplasia. In the first and third rounds, the slides were classified according to the 1975 classification and in the second and fourth rounds according to the 1994 classification. The overall interobserver agreement in the two rounds where the 1975 classification was used was 0.47 and 0.51, and the k values 0.24 [95 confidence interval (CI) 0.21–0.27] and 0.30 (95 CI 0.27–0.33). The overall interobserver agreement in the two rounds using the 1994 classification was 0.45 and 0.41 and the k values 0.25 (95 CI 0.23–0.28) and 0.20 (95 CI 0.17–0.22). Reducing the classification to two categories with clinical significance (atypical endometrial hyperplasia versus others in the 1975 classification, and atypical endometrial hyperplasia, complex versus others in the 1994 classification) increased the overall agreement of the 1975 classification in both rounds to 0.91 and of the 1994 classification to 0.92 and 0.90. The k values increased to 0.54 (95 CI 0.49–0.58) and 0.49 (95 CI 0.45–0.54) in the 1975 classification and to 0.59 (95 CI 0.54–0.63) and 0.42 (95 CI 0.37–0.46) in the 1994 classification. The intraobserver overall agreement for the 1975 classification ranged from 0.80 to 0.55 and the k values from 0.70 (95 CI 0.58–0.81) to 0.28 (95 CI 0.17–0.39). The intraobserver overall agreement for the 1994 classification ranged from 0.71 to 0.46 and the k values from 0.60 (95 CI 0.51–0.70) to 0.20 (95 CI 0.09–0.30). It is concluded that there is considerable inter- and intraobserver variation using both the 1975 and the 1994 classifications of endometrial hyperplasia. We propose that there is need for a specification and for a simplification of the classification.

To study the analyte evaporation and desolvation capacity of the microwave plasma torch (MPT), as a new source for atomic spectrometry, the radially-resolved rotational temperatures as a good approximation for the gas-kinetic temperatures were determined. An atmospheric pressure microwave discharge in argon at a frequency of 2.45 GHz at a power of 100 W and a gas flow rate of 0.6 l min⁻¹ was studied. The procedure makes use of the rotational fine structure of the (A²Σ⁺→X²Π_i) OH band at 306.4 nm and the temperatures were obtained from the slope of a Boltzmann plot. To obtain spatially-resolved intensities and for simultaneous detection of the different rotational lines, a charge coupled device (CCD) combinend with a Czerny–Turner monochromator was used. The image of the axially-symmetric plasma was rotated with the aid of a three-mirror arrangement by 90° and imaged onto the entrance slit. Radially-resolved intensities were calculated by means of an Abel inversion and measurements at different observation heights allowed complete tomography of the plasma. For the Abel inversion and temperature determination, an Interactive Data Language (IDL) program was developed, which computes the results in a short time and allows the presentation of the results as colour contour-plots. A mean temperature of about 3600 K with an error below 10% was found under the conditions mentioned above. Also the influence of power and water-loading of the carrier gas was investigated. Both were found to affect the temperature distribution but no significant changes in the mean temperature could be observed in the range 70–170 W and at a water-loading of between 0.6 and 9.0 mg min⁻¹ of argon.

Applying a transparent tool technique the tool/workpiece interface in plane strip drawing of aluminium is studied. The strips are provided with macroscopic lubricant pockets, and the compression and eventual escape of trapped lubricant by the mechanisms Micro Plasto Hydro Dynamic Lubrication (MPHDL) and Micro Plasto Hydrostatic Lubrication (MPHSL) is observed and quantified experimentally with respect to the lubricant pocket parameters, shape, volume, and angle to the edge. The two mechanisms have proved to depend very differently upon these parameters. The level at which the hydrostatic pressure is stabilised is shown to be independent of the volume of a pocket and the MPHDL mechanism is therefore solely dependent on the angle to the edge, which is shown both experimentally and theoretically by a fluid mechanic analysis. For the MPHSL mechanism a dependency of the volume is observed.

For an economic production with a high process reliability, an increased tool life is required. Therefore, the necessity exists to give a reliable estimation of the tool life during the design of new tool systems. Especially for cold forging processes, the failure caused by surface fatigue is characteristic. Different approaches are suitable to calculate the time period until the initiation of fatigue cracks. The aim of this paper is to assess the applicability of different failure concepts for a closed cold forging die. The critical, process-dependent load is quantified and localized by using a finite element method. Based on the resulting stress–strain distributions, the damage parameters are calculated yielding different estimates of tool life that are compared with practically experienced data.

For an economic production with a high process reliability, an increased tool life is required. Therefore, the necessity exists to give a reliable estimation of the tool life during the design of new tool systems. Especially for cold forging processes, the failure caused by surface fatigue is characteristic. Different approaches are suitable to calculate the time period until the initiation of fatigue cracks. The aim of this paper is to assess the applicability of different failure concepts for a closed cold forging die. The critical, process-dependent load is quantified and localized by using a finite element method. Based on the resulting stress–strain distributions, the damage parameters are calculated yielding different estimates of tool life that are compared with practically experienced data.

In forming technology non-destructive testing (NDT) methods are already quite established in basic and industrial research as well as in practice. Due to the continually enhanced capabilities of these methods, new fields of application can be expected in future. In this paper recent developments in experimental and evaluation techniques for three such new applications are presented. The first is the ultrasonic in situ inspection of the real contact area (RCA) between billet and tool in upsetting. It is demonstrated that the evolution of the RCA during the forming process can be measured with high lateral resolution and good reproducibility. The second application deals with the examination of the state of pre-stressing of extrusion dies reinforced by a stress ring. Again the ultrasonic method is applied and is shown to be suited to give detailed information about the conformity of the reinforcement. Finally, the well-known method of material characterization based on the magneto-inductive principle is adapted to the task of on-line quality control in sheet metal forming. The applicability and efficiency of this method are verified by experimental results.

In modern sheet metal forming, blank topographies are characterized by various quite different and rather sophisticated structures. This is due to the various deterministic or semi-deterministic methods of surface texturing produced by skinpass rolling. The conventional surface parameters determined from profile data are not capable of characterizing such surfaces, in particular with respect to their functional behavior. Thus, there is a strong demand for the development of new parameters which can only be determined via the measurement of area. With special respect to the application of deterministically textured topographies in metal forming, appropriate 3d surface parameters can be derived from the mechanical rheological model recently developed at the Institute of Manufacturing Technology. These are the maximum ratio of closed void area and the closed void volume, both of which result from a special evaluation of the bearing ratio curves. Industrial applications show that these parameters can be related to the functionality of the surface and hence may be regarded as very suitable for the characterization and qualification of complex surface structures.

In this study a test method is presented in which buckling phenomena can be investigated at a fundamental level. A rectangular sheet sample is fixed in a specially designed mounting device which transfers tensile forces in the longitudinal direction as well as compressive forces in the perpendicular direction. The mechanical principle used ensures a steady ratio of the corresponding strains. Onset and growth of the wrinkle can be monitored by special measuring equipment. The aim of the experimental and theoretical investigations described in this paper was to check the operational characteristics and capabilities of the equipment and to deduce a reproducible criterion for the formation of wrinkles.

Nicotine (2×10-4 M) or acetylcholine (5.5×10-4 M) in the presence of 3×10-6 M atropine did not increase the rate or amplitude of contraction in isolated atria or ventricular strips of the chicken heart; both drugs also did not cause an output of noradrenaline or adrenaline and did not evoke antidromic discharges in the right sympathetic nerves of isolated perfused chicken hearts. In contrast, “high K+-solutions” evoked an output of noradrenaline and adrenaline and caused a burst of antidromic discharges. Dimethylphenylpiperazine (DMPP; 3.1×10-4 M), by a tyramine-like action, elicited a small output of noradrenaline and increased rate and amplitude of contraction, but did not evoke antidromic discharges. The noradrenaline output caused by DMPP was not reduced by lowering the extracellular Ca2+ concentration from 1.8 to 0.1125 mM.-Acetylcholine (10-5 and 10-4 M) inhibited the noradrenaline and adrenaline outputs evoked by electrical stimulation of the right sympathetic nerves (3 Hz, 1 ms, 30 V); the inhibition was blocked by 3×10-6 M atropine. —It is concluded that the terminal parts of sympathetic nerves of the chicken heart posses muscarinic inhibitory receptors but lack nicotinic excitatory receptors. Thus prejunctional nicotinic receptors are not an integral part of the terminal sympathetic neurone otherwise they would be present at this neurone in all species.