Increased diurnal plasma concentrations of dehydroepiandrosterone in depressed patients

Activation of the hypothalamus-pituitary-adrenocortical system is a biological core symptom of depression. Although the regulation of cortisol secretion is well studied in this condition, there is no information about the diurnal activity of dehydroepiandrosterone (DHEA) secretion. Therefore, we studied 24-h DHEA plasma concentrations (every 30 min) in severely depressed patients (n = 26) and healthy controls (n = 33). We found depression to significantly increase diurnal minimal and mean DHEA plasma concentrations, whereas there was no effect on the diurnal maximal plasma concentration and the diurnal amplitude of DHEA. In particular, we found a parallel increase in mean DHEA (5.8 +/- 3.6 vs. 3.4 +/- 1.9 nmol/L; P < 0.003), cortisol (286 +/- 65 vs. 184 +/- 29 nmol/L; P < 0.0001) and ACTH (7.14 +/- 2.06 vs. 5.72 +/- 1.36 pmol/L; P < 0.002) plasma concentrations. The novel finding of parallel increases in diurnal DHEA and cortisol plasma concentrations in depressed patients has important implications for the regulation of the hypothalamus-pituitary-adrenocortical system in conditions of chronic stress and for the rationale of DHEA treatment in depressed patients.     

Methodische Untersuchungen zur phasentrennenden Fraktionierung von Polycaprolactam,

The carbonyl group concentration was determined with C-14 labelled 2,4-dinitrophenylhydrazine in the following substances: pergamin, filterpaper, cellophane, polyethylene and polypropylen. For standardizing the method, the MALAPRADE-splitting of the C₂? C₃-bond in the glucosidic unit of celluloses was used. The reactivity towards NaJO₄ increased in the following way: cellophane < filterpaper < pergamin.     

Bewertung von Varianten zum Umbau einer Mittelspannungs-Netzschaltanlage mittels Zuverlässigkeitsanalyse

The necessary replacement of a 20-kV-substation gave the reason for a reliability based assessment of the elaborated alternatives. The assessed medium voltage network consists of 3 open rings and around 100 transformer stations. This paper deals with the significance and usability of the assessment results concerning network planning; especially the deficit energy of the system and the single customer are taken into account.     

Anwendung der Random‐Set‐Methode (RSM) für Standsicherheitsuntersuchungen im Tunnelbau

Application of the Random Set Method (RSM) for stability analyses in tunnel construction. This paper discusses the application of the Random Set Method (RSM) in tunnel construction. It shows the benefits, by means of an example, of using RSM for stability analyses. The results of the calculation using state‐of‐the‐art deterministic methods are compared with the results of RSM, which cover the entire range of parameters of a homogeneous section of a tunnel. For this investigation it is postulated that the stability of a tunnel is ensured when the actual deformations correspond with the calculated deformations. If the stability analysis is made using a deterministic approach, a significant degree of interpretation is required for the evaluation and comparison of measurement and calculation results. This is not the case when using RSM because the full range of possible parameters enters the analysis as compared to selected parameter combinations.     

Formation of Technetium Salts in Hanford Low‐Activity Waste Glass

The distribution and physical form of technetium in a Hanford low‐activity waste (LAW) glass was examined with scanning electron microscopy (SEM) and X‐ray diffraction (XRD). A simulated Hanford LAW glass was spiked with varying amounts of potassium pertechnetate and melted at 1000°C. The glass was melted in a sealed quartz ampoule with the air pumped out, so that volatile material could leave the glass but would not be lost from the system. Previous studies have shown that technetium remains in the glass up to about 2000 ppm, but rises to the top of the melt as a separate salt phase above this concentration. Examination by SEM shows that crystals of technetium compounds appear to grow out of the hot glass, which implies that the hot glass was supersaturated in technetium salts. Some of the technetium compound crystals had apparently melted, but other crystals had obviously not melted and must have formed after the glass had partially cooled. The technetium compounds in the salt layer are KTcO₄ and NaTcO₄, according to SEM and XRD. No TcO₂ was found in the salt phase, even though Tc(IV) has been previously reported in the glass.     

Bank stabilization,riparian land use and the distribution of large woody debris in a regulated reach of the upper Missouri River,North Dakota,USA

Large woody debris (LWD) is an important component of ecosystem structure and function in large floodplain rivers. We examined associations between LWD distribution and riparian land use, bank stabilization (e.g. riprap revetment), local channel geomorphology, and distance downriver from the dam in the Garrison Reach, a regulated reach of the upper Missouri River in North Dakota, USA. We conducted a survey of shoreline‐associated LWD in the reach during typical summer flow conditions. Reach‐wide LWD density was 21.3 pieces km^?1 of shoreline, of which most pieces (39% ) were ‘beached’ between the waterline and the bankfull level, 31% of pieces had evidence of originating at their current location (anchored), 18% of pieces were in deep water (>1 m), and 13% were in shallow water. LWD density along unstabilized alluvial (sand/silt) shorelines (27.3 pieces km^?1) was much higher than along stabilized shorelines (7.2 pieces km^?1). LWD density along forested shorelines (40.1 pieces km^?1) was higher than along open (e.g. rangeland, crop land; 9.2 pieces km^?1) or developed (e.g. residential, industrial; 7.8 pieces km^?1) shorelines. LWD density was highest overall along unstabilized, forested shorelines (45 pieces km^?1) and lowest along open or developed shorelines stabilized with a blanket‐rock revetment (5.5 pieces km^?1). Bank stabilization nearly eliminated the positive effect of riparian forest on LWD density. A predicted longitudinal increase in LWD density with distance from the dam was detected only for deep LWD (including snags) along unstabilized alluvial shorelines. Partial resurvey in the summer following the initial survey revealed a reduction in total LWD density in the reach that we attribute to an increase in summer flow between years. Changes in riparian management and land use could slow the loss of LWD‐related ecosystem services. However, restoration of a natural LWD regime in the Missouri River would require naturalization of the hydrograph and modification of existing bank stabilization and channel engineering structures. Copyright © 2004 John Wiley & Sons, Ltd.     

The dependence of the chemical potential of WO3 films on hydrogen insertion

Knowledge of the chemical potential of electrochromic films coloured by hydrogen is important for matching the elements of an electrochromic device, for understanding the colouring mechanism and for obtaining information about the microscopic structure of the film. The dependence of the chemical potential on the hydrogen concentration was measured electrochemically for tungsten oxide films of different crystallinity and water content. A new method for determining the chemical potential by catalytic coloration by hydrogen gas is introduced. It revealed that the increase in electromotive force with increasing crystallinity is due only to different binding energies of the protons. We expect the protons to be located in the centres of hexagons, which are created by WO₆ octahedra. According to our model, amorphous sputtered films show a hexagonal structure which is similar to that of evaporated films, but the hexagons are connected, leading to more hexagon centre sites, which increases the electromotive force.