Thickness uniformity measurements and damage threshold tests of large-area GaAs/AlGaAs crystalline coatings for precision interferometry.

Precision interferometry is the leading method for extremely sensitive measurements in gravitational wave astronomy. Thermal noise of dielectric coatings poses a limitation to the sensitivity of these interferometers. To decrease coating thermal noise, new crystalline GaAs/AlGaAs multilayer mirrors have been developed. To date, the surface figure and thickness uniformity of these alternative low-loss coatings has not been investigated. Surface figure errors, for example, cause small angle scattering and thereby limit the sensitivity of an interferometer. Here we measure the surface figure of highly reflective, substrate-transferred, crystalline GaAs/AlGaAs coatings with a custom scanning reflectance system. We exploit the fact that the reflectivity varies with the thickness of the coating. To increase penetration into the coating, we used a 1550 nm laser on a highly reflective coating designed for a center wavelength of 1064 nm. The RMS thickness variation of a two inch optic was measured to be 0.41 ± 0.05 nm. This result is within 10% of the thickness uniformity, of 0.37 nm RMS, achieved with ion-beam sputtered coatings for the aLIGO detector. We additionally measured a lower limit of the laser induced damage threshold of 64 MW/cm 2 for GaAs/AlGaAs coatings at a wavelength of 1064 nm.

Huddle test measurement of a near Johnson noise limited geophone.

In this paper, the sensor noise of two geophone configurations (L-22D and L-4C geophones from Sercel with custom built amplifiers) was measured by performing two huddle tests. It is shown that the accuracy of the results can be significantly improved by performing the huddle test in a seismically quiet environment and by using a large number of reference sensors to remove the seismic foreground signal from the data. Using these two techniques, the measured sensor noise of the two geophone configurations matched the calculated predictions remarkably well in the bandwidth of interest (0.01 Hz-100 Hz). Low noise operational amplifiers OPA188 were utilized to amplify the L-4C geophone to give a sensor that was characterized to be near Johnson noise limited in the bandwidth of interest with a noise value of 10-11 m/Hz at 1 Hz.

Early diagnosis of colorectal cancer: a preventive task in occupational health.

Morbidity of colorectal cancer is still accreting; therefore in 2003 a total of 57000 patients fell ill and about 28000 died due to colorectal carcinoma. According to the etiology, many different factors are currently in discussion. However, as in about 25-30% of the cases familial clustering can be observed one of the most probable might be the genetic predisposition. Nevertheless only in 3% of all cases this predisposition is also scientifically assured. The high average age of manifestation raised the question if there might be also an occupational relationship for colorectal carcinoma in tense of an occupational disease. Therefore there is sight for occupational health to contribute to early diagnosis of colorectal carcinoma within the scope of routine check-up, health management and research of occupational diseases.

[Iatrogenic lesion of the radial nerve--disability in domestic work concerning liability]. / Iatrogene Radialisschädigung--die konkrete Behinderung der Hausfrau in der Haftpflichtversicherung.

In liability cases caused by accidents, the actual compensation for consecutive sustained damage to the patients' health and pain is not sufficient. Moreover, besides payments for a loss of earning capacity, the compensation for loss of efficiency in daily life such as for domestic work might be necessary. Therefore, distinct indications for the expert's appraisal exist.

Repeated digital nerve block for pain control after tenolysis.

We describe a way of achieving immediate painfree mobilisation after tenolysis or tenosynovectomy in Zone II. Bupivacaine is instilled along the flexor tendon sheath through a thin percutaneous catheter with an antibacterial filter.

Increase in choleresis by means of artichoke extract.

The choleretic action of artichoke extract [main ingredient: cynarin (1.5-di-caffeoyl-D-quinc acid)] was investigated in a randomised placebo-controlled double-blind cross-over study (pilot study) [n = 20]. The effect of the standardized, artichoke extract: Hepar SL forte (administered as a single dose: 1.92 g, by the intraduodenal route in a solution of 50 ml of water) was studied by measuring intra-duodenal bile secretion using multi-channel probes. Thirty minutes after the test-substance was administered, a 127.3% increase in bile secretion was recorded, after 60 minutes, 151.5%, and after another 60 minutes, 94.3%, each in relation to the initial value. The relevant differences for the placebo were significant to the extent of p < 0.01 and were clinically relevant. The highest increase in the case of the placebo (139.5%) was seen after 30 minutes. At 120 and 150 minutes the volume of bile secreted under the active treatment was also significantly higher than under the placebo (p < 0.05). In the placebo group, bile secretion fell below the initial level after 3 hours. An effective period of about 120-150 minutes was regarded as satisfactory to influence enzymatic digestion and the motor function of the intestine when the test substance was given postprandially. No side effects nor changes in the laboratory parameters in connection with the experiment were observed. Results indicate that artichoke extract can be recommended for the treatment of dyspepsia, especially when the cause may be attributed to dyskinesia of the bile ducts or disorder in the assimilation of fat.

[Cholestatic jaundice during lovastatin medication]. / Cholestatischer Ikterus während Lovastatin-Einnahme.

A 48-year-old man had type IIb hyperlipoproteinaemia which could not be satisfactorily treated with diet alone (total cholesterol 351 mg/dl, HDL cholesterol 36 mg/dl, triglycerides 480 mg/dl). Treatment with lovastatin (an HMG-CoA reductase inhibitor) was then started at a dosage of 20 mg daily. After two months on the drug cholestatic jaundice developed (total bilirubin 6.15 mg/dl). The jaundice and abnormal biochemical findings regressed within two weeks of discontinuing lovastatin. All other possible causes of jaundice were excluded. These observations indicate that, in addition to hepatocellular damage, lovastatin may in rare instances also exert a cholestatic effect.

[A new organ perfusion system: Successful preservation of kidney function for 72 hrs (author's transl)]. / Ein neues Gerät zur Organperfusion: Erfolgreiche Konservierung der Nierenfunktion über 72 Stunden

A new preservation system is described. In this unit 17 dog kidneys were nonpulsatile perfused with hypothermic human albumin for 72 hrs and then transplanted. All kidneys started immediately to function and the PAH and inulin clearances attained normal values at least at the 7th postoperative day. The quality of the immediate function is referred to the applied perfusion pressure (20 mm Hg) and the applied temperature of the perfusion medium (7.5 degrees C). During preservation substrate utilization (oxygen, unesterified fatty acids) and the accumulation of toxic metabolic products (ammonia, uric acid) were controlled in the perfusate. Their importance concerning to the limitation of preservation time is discussed.

Analysis of the optimal perfusion pressure and flow rate of the renal vascular resistance and oxygen consumption in the hypothermic perfused kidney.

Thirty-six dog kidneys were perfused with different perfusion pressures (between 15 and 60 mm. Hg) for 72 hours and then transplanted. Hypothermic human albumin was the perfusion fluid. Enzyme release, kidney weight, and renal oxygen consumption were measured during perfusion. Kidneys perfused with a flow rate of 0.8 ml. per gram per minute (21 mm. Hg mean perfusion pressure) showed the smallest increase in kidney weight and the best function after transplantation. Renal vascular resistance was independent of the level of the perfusion pressure and renal oxygen consumption was independent of the applied flow rate. It is concluded that the perfusion pressure applied with hypothermic perfusion should be as low as possible because in this way kidney damage caused by perfusion can be avoided most easily.

[Optimum perfusion pressure, renal resistance and oxygen consumption of kidney in hypothermic pulsating perfusion]. / Untersuchungen über den optimalen Perfusionsdruck, den renalen Widerstand und den Sauerstoffverbrauch der Niere bei hypothermer pulsierender Perfusion

36 dog kidneys were perfused with different perfusion pressures (between 15 and 60 mm Hg) for 72 hrs and then transplanted. Hypothermic human albumin was the perfusion fluid. Kidneys perfused with a flow rate of 0.8 ml/g/min (21 mm Hg mean perfusion pressure) showed the smallest increase in kidney weight and the best function after transplantation. Renal vascular resistance was independent of the level of the perfusion pressure and renal oxygen consumption was independent of the applied flow rate.