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Industrial thin slab casting and direct rolling processing started in 1989 with the world’s first CSP® plant at Crawfordsville (USA). Since this time CSP® and competing thin slab casting and direct rolling concepts have been developed to a standard process for hot strip production. Typical features of the CSP® process are the homogeneous structural and mechanical properties all along the strip. Direct hot rolling of thin slabs may be followed by a well defined cooling pattern to produce fine-grained HSLA steel or multiphase hot strip on the runout table. The product range covers low carbon as well as medium and high carbon steel grades comprising IF-, HSLA-, API-, electrical- and multiphase steel grades. CSP® processed thin hot strip is used for non-exposed parts and may substitute cold rolled strip. Hot strip from thin slab can be easily further processed to cold rolled and/or surface treated strip. Today process and material developments e.g. go for energy saving, rise in productivity, advanced surface requirements, HSLA and multiphase steel grades combining higher strength and ductility as well as multiphase steel grades for hot dip galvanizing.

Chronische Ruckenschmerzen sind haufige Klagen im ambulanten orthopadischen Praxisbetrieb. Nationale (DEGAM; Deutsche Gesellschaft fur Allgemeinmedizin und Familienmedizin) und internationale Leitlinien geben Empfehlungen zum diagnostischen und therapeutischen Vorgehen. Uber das Verordnungsverhalten behandelnder Orthopaden im Rahmen der Therapie ist bislang jedoch nur wenig bekannt.

Modern inland vessels are open-top, double-hull ships with unusually large length-to-beam and length-to-height ratios, shallow draught and an extremely long cargo hold. Therefore, they have low bending and torsional rigidity. Moreover, the state of the ship structure changes appreciably in course of service due to minor collisions, groundings in shallow water, corrosion and fatigue. Such imperfections reduce the stability and strength of the structure. The safety against collapse decreases. This paper shows the results of a systematic investigation of a typical push-barge structure using the finite-element-method.

Of all the elements, hydrogen has the largest naturally occurring variations in the ratio of its stable isotopes (D/H). It is for this reason that there has been a strong desire to add hydrogen to the list of elements amenable to isotope ratio monitoring gas chromatography/mass spectrometry (irm-GC/MS). In irm-GC/MS the sample is entrained in helium as the carrier gas, which is also ionized and separated in the isotope ratio mass spectrometer (IRMS). Because of the low abundance of deuterium in nature, precise and accurate on-line monitoring of D/H ratios with an IRMS requires that low energy helium ions be kept out of the m/z 3 collector, which requires the use of an energy filter. A clean mass 3 (HD(+.)) signal which is independent of a large helium load in the electron impact ion source is essential in order to reach the sensitivity required for D/H analysis of capillary GC peaks. A new IRMS system, the DELTA(plus)XL(trade mark), has been designed for high precision, high accuracy measurements of transient signals of hydrogen gas. It incorporates a retardation lens integrated into the m/z 3 Faraday cup collector. Following GC separation, the hydrogen bound in organic compounds must be quantitatively converted into H(2) gas prior to analysis in the IRMS. Quantitative conversion is achieved by high temperature conversion (TC) at temperatures >1400 degrees C. Measurements of D/H ratios of individual organic compounds in complicated natural mixtures can now be made to a precision of 2 per thousand (delta notation) or, better, with typical sample amounts of approximately 200 ng per compound. Initial applications have focused on compounds of interest to petroleum research (biomarkers and natural gas components), food and flavor control (vanillin and ethanol), and metabolic studies (fatty acids and steroids). Copyright 1999 John Wiley & Sons, Ltd.

We summarize results for surface reaction rate constants and diffusion coefficients obtained for Fe-doped SrTiO 3 by different techniques, and report on novel results derived from permeation experiments (chemical relaxation). This technique is particularly well-suited to investigate surface and bulk kinetics without auxiliary phases (e.g., electrodes) in a single experiment. The measured diffusion coefficients are in excellent agreement with values predicted from defect chemical modelling. The surface rate constants are less precisely understood but fit into the major trends inferred from previous measurements.

In order to avoid ruptures of a metal strand in continuous casting machines a matrix of numerous temperature sensors is applied to monitor the temperature profile of the strand. The need for frequent reconstruction and maintenance of the ingot mold leads to efforts with respect to the cabling of the numerous sensors. In this paper a prototype of a completely wireless thermoelectrically powered temperature sensor is introduced. The solution includes the energy-harvesting and sensor electronics and a robust sensor design. The approach of the dimensioning is described and the relevant energy harvesting components are characterized in the trial. Measurements show that the developed thermoelectric powered sensor can transmit every second up to 28 bits of user data in addition to a 32 bit unique sensor ID if a temperature difference of 16 °C between the sensors hot surface and the ambient air is given. Introduction A rupture of a metal strand is one of the most severe disruptions that can happen during steel production. To avoid this accident, it is essential to measure the temperature profile of the metal strand in order to identify the development of cracks [1]. For this task a matrix of up to 120 spatially distributed temperature sensors is used. The setup of a typical continuous casting plant is depicted in Fig. 1. The sensor matrix is located at the inner side of the ingot mold that is oriented towards the molten metal strand. The cabling of the numerous sensors causes notable problems with respect to installation efforts and reliability. In addition, if the ingot mold needs to be re-arranged, the required adjustment of the cabling leads to long and thus costly downtimes. To overcome this problem, a concept for a wireless sensor system has been developed. It is proposed that a thermoelectric generator (TEG) utilizes the process heat of the ingot mold as an energy source. The sensor is screwed into the hot mold wall, so that the absorbed heat can pass through the TEG mounted in the interior of the sensor to the ambient air. The temperature is measured with a sensing element in a probe that is pressed against the inner side of the ingot mold. The extreme high humidity, pollution by settled dust, the potential mechanical forces, and the need for an easy installation and handling were considered in the sensor design. As usually the electronic part of the energy harvesters consists of an energy converter, an energy conditioner, and an energy storage (see Fig. 2). The storage supplies a microcontroller that manages the supply and the data conversion for the transducer and the RF transmitter module. A simple low power transmission protocol with a low probability of collision is used for the radio transmission. thermoelectric generator (energy converter) DC/DC converter (energy conditioner) capacitor (energy storage) microcontroller RF transmitter resistance (sensing element) transducer STM 110 Fig. 2: Schematic of the sensor electronics tundish with liquid steel water-cooled ingot mold extension bolt with counternut extension bolt with wireless sensor soft steel strand exemplary temperature measuring point C 1.4 Fig. 1: Soft steel strand S E N S O R + T E S T C o n f e r e n c e s 2 0 1 1 S E N S O R P r o c e e d i n g s 3 8 1 Design of the Thermoelectric Energy Converter For a suitable choice of the energy converter several Seebeck elements were investigated. Their parameters were determined experimentally. The results are summarized in Tab. 1. To ensure efficient energy conversion the modules need to have a high Seebeck coefficient, a low internal resistance, and a low thermal conductivity. Since all parameters rise with the number of thermocouples it is possible to increase the thermoelectric efficiency [2] by optimizing the material composition of the used thermocouples. A preferred material composition is characterized by a highest possible figure of merit [2], as in the example of the TEG 1. Other manufacturers rely on temperature resistant and mechanical robust modules such as the TEG 2. However, because of the used polyimide insulation between the thermocouples in order to stabilize the structure, these modules are attended by a loss of the thermoelectric efficiency. Also the TEG 3 does not has a high figure of merit, but considering its small surface an excellent power factor [2]. The TEG 3 is an extremely miniaturized module, based on a novel production technology. Depending on the restrictions of the application (for example weak heat source, high temperature or low space) the type of the TEG should be selected. The bold parameters in the table show the main highlight of each TEG type. Tab. 1: Measured parameters of tested Seebeck elements description TEG 1 TEG 2 TEG 3 manufacturer Eureca HI-Z Micropelt model TEG1-30-30-2.1 HZ-2 MPG-D751 maximum temperature 150 °C 250 °C 200 °C area 900 mm2 841 mm2 13.9 mm2 height 3.6 mm 5.1 mm 1.1 mm number of thermocouples 128 98 540 Seebeck coefficient 34.1 mV/K 18.3 mV/K 99 mV/K internal resistance 6.5 Ohm 3.4 Ohm 524.6 Ohm thermal conductivity 0.23 W/K 0.33 W/K 0.15 W/K figure of merit 779 1/K 302 1/K 124 1/K power factor 4.97 μW/(K2·cm2) 2.93 μW/(K2·cm2) 32.68 μW/(K2·cm2) When choosing the appropriate energy converter, the thermal sensor assembly and the environmental conditions must be considered as well. This includes the absorption and dissipation of the heat, as well as the arrangement and mounting of the TEG. The hot side has to provide enough heat and the cold side has to release enough heat to produce a sufficiently large and durable temperature difference for the TEG. A simplified arrangement with an infinite heat source and a heat sink with a finite energy transfer are shown in Fig. 3. With the hot side temperature and the ambient temperature the temperature difference at the TEG can be calculated by (1) Fig. 3: Parallel array of thermoelectric generators S E N S O R + T E S T C o n f e r e n c e s 2 0 1 1 S E N S O R P r o c e e d i n g s 3 8 2 where represents the thermal conductivity of the heat sink and the thermal conductivity of a single TEG [3]. The losses of the thermal coupling and other thermal bridges are neglected in this approach. The number of the TEGs reduces the effective temperature difference due to the additional heat flows with the result that the heat sink heats up to the temperature . Assuming identical modules with a Seebeck coefficient the thermoelectric voltage at each TEG is given by

Complete chromatographic separations of a wide range of different tropane alkaloid stereoisomers on a commercially available cellulose-based chiral stationary phase (CSP) are described. The separations were achieved by using cellulose tris(3,5-dimethylphenyl) carbamate as CSP with both an aqueous and an organic mobile phase with different ionic modifiers. The effects of totally different modifiers in both mobile phases on the chromatographic resolution are described.

Chronic back pain is a frequent complaint in out-patient orthopaedic practice. National (DEGAM; German Society of General Medicine and Family Medicine) and international guidelines provide recommendations for diagnostic and therapeutic procedures. Regulation of the behaviour of treating orthopaedists in the context of the therapy is so far little known.In this survey it was investigated which treatments are prescribed, whether there is a link between regulations and stage of chronification and whether the subjective effects correspond to objective results. Questionnaires relating to patient anamnesis were sent to 235 orthopaedic practices and a second questionnaire was sent to all patients who took part in the survey 6 months later. A total of 630 data sets could be evaluated.It was shown that primarily passive therapies (physiotherapy, drug therapy, injections and tablets) are mostly prescribed (physiotherapy, medications, injections) and that more therapies are used with increasing stages of chronification. The prescribed therapy achieved a high subjective patient satisfaction but an objective success could not be recognized.

Thin Pd films are used as protective layers against reoxidation of cleaned less noble metals in order to allow an easy hydrogen uptake. The hydrogen permeability through the Pd-films into the substrate metal depends strongly on the film preparation conditions especially on the deposition rate and substrate temperature during deposition. Various measurements (including resistivity, electrochemical diffusion, SIMS and AES, gravimetrical and X-ray diffraction measuring techniques) have been applied to characterize film samples prepared in different ways in order to find the optimal conditions to prepare protective but hydrogen permeable Pd-films. It could be shown that the hydrogen uptake from the gas phase is mainly determined by adsorption layers on the film surface, additionally the hydrogen permeability is closely connected with the structure of the interface between film and substrate. Low deposition rates and increased substrate temperatures during preparation are the basis to obtain Pd-films with best properties for an easy hydrogen uptake and permeability.

The buffer substance tris(hydroxymethyl)aminomethane (Tris) is converted to formaldehyde in an hydroxyl radical producing model system and in rat liver microsomes, and to CO2 in rat hepatocytes and in the intact rat. In microsomes, formaldehyde formation from Tris is inhibited by catalase, by the antioxidant propylgallate and by the iron chelator deferoxamine, formaldehyde formation is stimulated by the addition of Fe (II) EDTA. In hepatocytes, the formation of [14C] CO2 from [14C] Tris is inhibited by propylgallate and by the iron chelator o-phenanthroline and is stimulated by the presence of a xanthine oxidase system plus Fe (II) EDTA in the medium. In the intact rat, the administration of [14C] Tris results in the exhalation of [14C] CO2. The results indicate that an oxidant formed via a Fenton-type reaction, possibly the hydroxyl radical, may be involved in the formation of one-carbon compounds from Tris.

Haufig treten Drogenabhangige in den Praxen niedergelassener Arzte mit dem Wunsch auf, sich Suchtmittel verschreiben zu lassen, aber auch, um sich uber eine Langzeittherapie oder eine qualifizierte Substitutionstherapie zu informieren. Nur ungern ubernehmen die meisten Arzte die Behandlung dieser Patienten. Das hat nach meiner Erfahrung zwei wesentliche Grunde: 1. Andere Patienten nehmen Anstos an der oft nicht sehr gepflegten Erscheinung der Abhangigen und an ihrem wenig angepasten, oft forderndem Verhalten. 2. Die Suchtkranken haben immer wieder die gleichen Wunsche nach Suchtmitteln, wie z. B. Remedacen® und Rohypnol®, die wir nicht erfullen konnen und wollen.

The paper summarizes the main results obtained during the first six months of experimental work on TEXTOR with ohmically heated plasmas. The machine(R = 175 cm; a = 45-50 cm) was operated at wall temperatures up to 303 oC with hydrogen gas, a toroidal field of 2 T and a maximum plasma current of 500 kA, yielding central electron temperatures of 1.2 keV, maximum line-averaged densities of 4 x 1013 cm-3 and discharge durations of up to 2.7 sec (for Ip≤340 kA). Besides providing long-lasting reproducible plasmas for forthcoming plasma wall interaction research, the following tasks were accomplished: (1) control of low Z impurities by effective wall cleaning and conditioning; (2) accurate plasma positioning for extended pulse durations; (3) determination of the current density distribution by way of Faraday rotation measurements; (4) investigation of plasma limiter interaction including spectroscopic determination of released neutral particle fluxes and measurement of the power density distribution in the scrape-off layer by infrared-thermography.

Thirty-eight insulin-dependent diabetic subjects were treated for periods ranging from 1 to 14 mo with human insulin (recombinant DNA) in order to investigate the clinical effects of human insulin in comparison with pork insulin. Human insulin was well tolerated and no side effects were detected. The following differences between human and pork insulin were observed: reduced blood glucose oscillations associated with a reduction in hypoglycemic symptoms in patients with “brittle” diabetes and type I diabetes, decreased concentrations of antibodies against pork insulin related to a reduction of insulin requirement of §15%, increased specific receptor binding in patients with type I diabetes and insulin resistance: type A, possibility for treating patients with pork insulin allergy, and an increased biologic activity in a patient with polyclonal antireceptor antibodies. No difference was detected between pork and human insulin treatment in patients with type II diabetes and in a patient with insulin resistance: type B with monoclonal antireceptor antibodies. Human insulin was used safely and successfully in the treatment of diabetic patients.

The biologic effect of human insulin (recombinant DNA) and purified pork insulin (PPI) was compared during insulin-induced hypoglycemia at two intravenous dosages 0.075 and 0.1 U/kg body wt in 12 healthy volunteers. Serum insulin concentrations and plasma glucose curves were identical. PPI induced a significantly (P < 0.05) higher output of epinephrine, growth hormone, and cortisol at both doses. Less inhibition (P < 0.05) of endogenous insulin secretion was observed for human insulin at 0.1 U/kg body wt. An elevated incidence of sweating during hypoglycemia was related to epinephrine secretion. The results indicate that homologous insulin produces in vivo effects which are different from those produced by heterologous insulin.

The carbonization of the metallic liner and limiters of TEXTOR led to plasmas which contained less than 10−5 metal, and, in best cases, (0.6 ± 0.4)% low Z ions per D+. However disruptions damaged some of the carbon film and evaporated metal atoms. These were redeposited on the carbon layer and became a source of impurities. Graphite limiters have been used since mid-1985. The metal pollution is not a problem for more than 1000 discharges after one carbonization. However the low Z contamination was initially five times larger than earlier. Surprisingly, the oxygen concentration had considerably increased. Experiments were performed to identify the sources of C and O and to improve the conditioning methods in this “all carbon” surrounding. The main tools used were: RG (radiofrequency assisted DC glow) discharges in H2, D2, and their mixtures with CH4 and CD4, the study of the H/D ratio in water and hydrocarbons and of the CO and CO2 released during the ramp heating and cooling of limiters, liner, vessel and main portholes, and the modulation of the deuterium fluxes to the liner and limiters during tokamak discharges. The quality of tokamak plasmas measures the progress of the wall conditioning. We describe the optimized conditioning procedure which was applied after the most probable oxygen source had been drastically reduced.

The liner and limiters of TEXTOR have been coated in situ with a boron containing carbon film using a RG discharge in a throughflow of 0.8 He + 0.1 B2H6 +0.1 CH4. The average film thickness was 30–50 nm, the ratio of boron and carbon in the layer was about 1:1 according to Auger Electron Spectroscopy. Subsequent tokamak discharges are characterized by a small fraction of radiated power ( OVI/ n e of the OVI intensity normalized to the averaged plasma density n e decreases by more than a factor of four. The decrease in the oxygen content manifests itself also as a reduction of the CO and CO2 partial pressures measured during and after the discharge with a sniffer probe. The carbon levels are reduced by a factor of about two as measured by the normalized intensity CII/ n e of the CII line and via the ratio of the C fluxes and deuterium fluxes measured at the limiter (CI/Dα). The wall shows a pronounced sorption of hydrogen from the plasma, easing the density control and the establishment of low recycling conditions. The beneficial conditions did not show a significant deterioration during more than 200 discharges, including numerous shots at ICRH power levels > 2 MW.

1 The effects of oral doses of pindolol (15 mg), metoprolol (200 mg) and propranolol (160 mg) on the response to insulin-induced hypoglycaemia and an oral glucose load were investigated. 2 Serum insulin and serum C-peptide secretion in response to a glucose load were inhibited (2P less than 0.01) by metoprolol and propranolol but not by pindolol. 3 During hypoglycaemia metoprolol and propranolol inhibited the clearance of insulin (2P less than 0.01) and caused a delay of glucose nadirs. 4 Adrenaline secretion during hypoglycaemia was markedly increased by metoprolol and propranolol but not by pindolol. 5 The counterregulatory response of growth hormone, ACTH and cortisol was increased following metoprolol and propranolol but not after pindolol. 6 The hypoglycaemic symptoms and signs showed a prevalence of sweating and prolonged changes in skin conductivity whereas palpitations were not observed during beta-adrenoceptor blockade. Asymptomatic hypoglycaemia did not occur. 7 The absence of unphysiological rises in adrenaline, growth hormone, ACTH and cortisol supports the use of a beta-adrenoceptor blocker with intrinsic sympathomimetic activity.

The performance of the TEXTOR tokamak, as manifested by its density limit, confinement time, behaviour of density and current density profiles, and impurity level, is described. By means of ICRH heating, powers significantly above the Ohmic one are obtained. The deposition of thin carbon layers onto all inner surfaces is shown to be an effective method for achieving low impurity concentrations in the plasma. Results of a systematic study of plasma-wall interaction, with particular emphasis on a quantitative description of the particle sources and of the boundary layer, are presented. Pump limiter experiments resulting in high particle removal rates are described.

TEXTOR, a tokamak primarily devoted to plasma-wall interaction studies, has been operated during the last 2–3 years under a wide variety of discharge conditions. Discharges with Ohmic heating only and with additional ICR heating in the MW-range were produced over an extended range of plasma parameters. Different limiter materials were used — Inconel, stainless steel, graphite, TiC coated graphite. The surface of the first wall (liner) consisted either of Inconel or of a carbon layer deposited upon the Inconel. Characteristic features of the discharge have been modified by making use of the modular pump limiter ALT-I and by applying a localized perturbation coil for “ergodization” of the magnetic field structure in the boundary. The characteristics of plasma-wall interaction under these conditions and their influence on the global performance of the TEXTOR plasma are described and discussed. Use has been made of novel diagnostics specifically developed for edge plasma investigation.

A theta pinch with 0.23-torr deuterium, 60-kG peak magnetic field and 1.8 μsec half cyclo has been further investigated. Three cases were observed: initial bias field of (a)zero, (b)+2kG, (c)—2 kG. For the interpretation of plasma phenomena one has to take into account non-stationary processes due to the ends. With —2 kG the usual axial contraction and heating rates of 1 keV/μsec were found. Both the incident and reflected axial shocks were measured, and they did not cause the trapped field to disappear or significantly increase the plasma radius even though the density increased by 2. With +2kG, β is a few per cent, and the plasma follows the field lines. Here Te < 80 eV. With zero field a rarefaction wave rims into the plasma causing a density increase by 2 and plasma diameter decrease. With zero field and —2 kG electron temperatures were comparable indicating that diffusion heating is also important in high- β cases (β 0.8). The x-ray and optical plasma radii agree within 1 mm. When one compares the time dependences of Te and ne it becomes questionable whether the soft x rays used for the determination of Te are thermal or not. With zero and —2-kG fields, discharge cleaning reduced impurities to 0.1o,o, and the reverse field and relatively high β, respectively, persisted through the entire half cycle. The usual abrupt reverse-field disappearance was observed with a few per cent impurity.

Human insulin (recombinant DNA) and purified porcine insulin were compared in healthy men. Intravenous insulin tolerance tests showed identical effects on plasma glucose when a bolus of 0.1 U/kg was injected. Following human insulin, hypokalemia and epinephrine secretion were significantly less pronounced. The differences in serum potassium concentrations are caused by a lower epinephrine response to hypoglycemia induced by human insulin in comparison to purified porcine insulin.

Fully synthetic human insulin (CGP 12'831) was compared to porcine insulin in identical and non-identical formulation by intravenous insulin tolerance tests in 12 volunteers. The half-lives of the three insulins tested did not differ (t 1/2: 5.5 +/- 0.2 minutes), though acid porcine insulin exhibited lower serum peak values. The hypoglycemic effects of the three insulins were identical. Human insulin produced a significantly smaller decrease in serum potassium (2p less than 0.01). The secretion of serum C-peptide was less inhibited by human insulin (2p less than 0.05). The counter-regulatory hormonal response of cortisol and growth hormone was lower after hypoglycemia induced by human insulin (2p less than 0.05). It is suggested that the hormonal effects of hypoglycemia are modified by human insulin and depend in part on the molecular structure of insulin.

The investigation on hand leads to the conclusion that HPRO can additively increase the blood glucose lowering effect of endogenous and exogenously administered insulin. Etiologically the prolonged retention time of HPRO in the circulation - compared to HI - must be primarily discussed. In the further course the question arises to what extent traditional retard insulins would have to be replaced or supplemented by HPRO.

Beta-adrenoceptor stimulation in vivo shifts potassium into the cells. To examine whether human erythrocytes participate in this process, we measured, along with serum or plasma potassium, the concentrations of potassium and sodium in erythrocytes. Beta-adrenoceptor stimulation was obtained by infusion of either fenoterol or hexoprenaline into 6 volunteers at rest or by endogenous amines provoked in 14 volunteers during ergometric exercise. Metabolic effects were followed at rest on serum insulin, C-peptide, and growth hormone levels, and during exercise on pH on lactate concentration in blood. The potassium concentration (mean +/- S.E.M.) dropped (p less than 0.01) in serum from 4.64 +/- 0.37 to 3.19 +/- 0.43 mmol x l-1 in the first hour at rest and in plasma from 5.70 +/- 0.93 to 4.63 +/- 0.45 in 90 sec directly after exercise. The concentration of erythrocyte sodium dropped (p less than 0.001) from 9.68 +/- 0.73 to 8.81 +/- 0.62 mmol x l-1 in cells and from 9.62 +/- 1.16 to 8.55 +/- 1.24 during exercise for 90 s, respectively. Changes in the concentration ratio of cellular sodium to potassium confirmed this sodium shift. An increased sodium transport in erythrocytes due to beta-adrenoceptor stimulation in vivo appears to complement a shift of serum potassium into the cells and may be mediated by the membrane-bound sodium, potassium ATPase.

To test whether proinsulin pretreatment can increase insulin effects, we studied the glucose lowering effect of insulin given intravenously as a bolus (9 mU/kg) following a two hour infusion of proinsulin (3 micrograms/kg body weight.h) in 11 healthy volunteers. Insulin was given directly after proinsulin infusion and two hours later. On a control day dilution medium has been infused only. The proinsulin dose chosen was able to reduce blood glucose significantly (from 4.30 to 3.81 mmol/l, P less than 0.05) without leading to increases in counterregulatory hormones. There were no significant changes in glucagon, growth hormone, adrenaline and noradrenaline, while cortisol showed a decline according to its diurnal rhythm during proinsulin infusion and control. Free fatty acids and glycerol as indicators of fat metabolism were reduced by 28.0% and 54.9% respectively, compared to reduction by 16.0% and 23.4% during control. Insulin injection directly after proinsulin infusion decreased blood glucose from 3.81 to 2.52 mmol/l. The decrease during control was from 4.38 to 2.98 mmol/l. Two hours after proinsulin infusion, blood glucose was decreased by insulin injection from 4.09 to 2.98 mmol/l, compared to a decrease from 4.08 to 3.19 mmol/l during control. No statistical significant effect of the preceding proinsulin infusion on insulin action could be demonstrated. Proinsulin seems to have no specific effect on either glucose or fat metabolism.

In the high-voltage experiment TENQ the compression phase of a belt-pinch was investigated. At initial electron densities of 3·1014 cm–3 no instability was observed during this phase. Finally a stable equilibrium -if slow vertical displacements are disregarded-with an axis ratio b/a = 4 is obtained. At initial density of 5·1013 cm–3, where mean ion energies of 180 eV could be obtained, instabilities localized in the region of strong curvature give rise to a fast loss of the confined plasma. It is concluded, that also during the compression phase the axis ratio b/a has not to exceed a critical value of about 5.

Simultaneous treatment with antidiabetic drugs and beta-adrenoceptor blocking agents is frequent on account of the high incidence of diabetes and cardiovascular disease. The effects of oral doses of pindolol, metoprolol, and propranolol on the response to insulin-induced hypoglycemia and an oral glucose load were investigated. During hypoglycemia metoprolol and propranolol inhibited the clearance of insulin (2 p less than 0.01) and caused a delay of glucose nadirs. This was not observed after pindolol. Epinephrine secretion and the counterregulatory response of growth hormone, ACTH and cortisol during hypoglycemia was significantly increased following metoprolol and propranolol but not after pindolol. The hypoglycemic symptoms and signs showed a prevalence of sweating and prolonged changes in skin conductivity while palpitations were not observed during beta-blockade. Asymptomatic hypoglycemia did not occur.

Counterregulatory secretion of epinephrine occurs during severe insulin-induced hypoglycemia. Under these conditions (minimal plasma glucose 27.4 ± 1 mg/dl) the decrease of serum potassium concentration (0.9 mVal/L) is mediated by two mechanisms: insulin-induced (0.48 mVal/L) and epinephrine-induced (0.42 mVal/L) cellular uptake of potassium. Epinephrine-induced serum potassium uptake appears to be more sensitive to beta-adrenoceptor blockade than glucose production. The intensification of insulin-induced hypokalemia by epinephrine is of clinical significance.

A now 12 year old boy developed diabetes mellitus when he was 7 years old. From 9 years on he developed progressive optic atrophy and deafness. Type I diabetes mellitus, together with progressive optic atrophy and several other symptoms like deafness, diabetes insipidus and ectasy of urinary tract are known for more than 40 years as autosomal-recessively inherited conditions. Therefore, in case of diabetes mellitus combined with optic atrophy it is necessary to search for further symptoms, developing during the course of the disease. Genetic counselling to the families is mandatory.

Magnesium concentrations in the blood plasma of patients with ventricular arrhythmias were found to be significantly lower than in controls, whereas the sodium and calcium concentrations of the erythrocytes were significantly higher than in the controls. Intensive magnesium therapy resulted in an increase of the plasma magnesium concentration and in significant changes of Na, K, Ca and Mg in the erythrocytes. By means of long-term ECG recordings, it was shown that the therapy may result in a quantitative decrease of the ventricular arrhythmias.

Counterregulatory effect following administration of biosynthetic human proinsulin (BHPI) and human insulin (BHI) were compared during hypoglycemia standardized by means of a glucose controlled insulin infusion system (GCIIS). A total of 0.148 +/- 0.010 U/kg of BHPI had to be given by the GCIIS in order to obtain a minimal blood glucose (BG) of 26 +/- 2 mg/dl (means +/- SEM) at 43 +/- 2 min. In contrast, 0.083 +/- 0.004 U/kg of BHI were sufficient to produce a minimal BG of 21 +/- 1 mg/dl (n.s.) at 35 +/- 1 min. (P less than 0.005). Moreover, BHPI infusion resulted in prolonged hypoglycemia and delayed blood glucose recovery. On a molar basis, the acute BG lowering effect of BHPI was about 13% that of BHI (BHPI 3.94 +/- 0.27 vs. BHI 0.51 +/- 0.03 nmol/kg). Serum proinsulin after BHPI reached its maximum of 19.4 +/- 2 pmol/ml at 20 min. and still exceeded basal values markedly at the end of the test period at 240 min. Serum insulin peaked at 10 min. (162 +/- 47 microU/ml) and had already returned to basal values (7.5 +/- 1 microU/ml) after 45 min. No severe side effects were observed and there was no need for glucose administration, but clinical symptoms of hypoglycemia were more pronounced after BHPI. Compared to BHI, BHPI produced a higher cortisol peak (252 +/- 16 vs. 168 +/- 10 ng/ml), a more pronounced secretion of ACTH and GH as well as a stronger decline of serum potassium (3.20 +/- 0.06 vs. 3.58 +/- 0.08 mmol/l). Counterregulatory prolactin secretion did not differ significantly. Urinary epinephrine secretion following hypoglycemia after BHPI exceeded that after BHI (10.3 +/- 4.8 vs. 3.0 +/- 0.5 ng/120 min.). Serum lactate increase after BHPI was more prolonged (1.68 +/- 0.24 vs. 0.37 +/- 0.14 mmol/l at 120 min.). BHPI-induced inhibition of lipolysis, as determined by free fatty acid patterns, was delayed and less pronounced. Our results indicate that the observed more distinct glucose counterregulation is due to prolonged hypoglycemia rather than to any specific BHPI action on the hypothalamic-pituitary axis. We regard this as a consequence of the prolonged circulating and biological half-life. A preferential proinsulin action on the liver may play an additional role. Whether this "depot effect" may be beneficial in the treatment of diabetes mellitus remains to be established.