Vorrichtung zum Bestimmen wenigstens einer Schichtdicke: Vorrichtung zum Bestimmen von Schichtdicken (A1)

In a device for the measurement of coating thicknesses based on white light interferometry, the output light (2) of a broadband light source (1) can be focused within a focal range (35) onto the object under test (37) by means of a focussing unit (7). By changing the optical path length in an object arm (19) by means of a beam deflection device (24), a focal range (35) can be shifted via bounding surfaces (36, 38, 39, 40) of the object (37). Interference signals can be produced with a high contrast and a high signal-to-noise ratio by time coherence and spatial superposition of the wave fronts curved by focussing the light component (18) back-reflected in the object arm (19) with a light component (15) passing though a reference arm (14). The position of the interference signals in relation to the shifting of the beam deflection device (24) can be evaluated by an evaluating unit which consists of a voltage-controlled oscillator and a phase-independent synchronizing rectifier. The coatin g thicknesses result from determining the distance between the interference signal maxima in relation to oscillation periods of the voltage-controlled oscillator controlled by the signal proportional to the shift velocity

The fiber Fabry-Perot and its applications as a fiber-optic sensor element

The applications of the Fiber-Fabry-Perot (FFP) as demonstrated in the laboratory are shortly reviewed. The FFP has been used as optical spectrum analyzer, as a reference element for laser diode frequency stabilization, and as a sensing element for the measurement of temperature, mechanical vibrations, and electric and magnetic fields. A new FFP strain gauge sensor element is reported thata is made from a gradient index fiber. Its main advantages are easy coupling between light supplying and signal transmission fibers to the FFP as well as a modular configuration of the FFP sensor. A signal evaluation method is described that identifies the sign of measurand change and allows for large intensity losses on the transmission module

Optically excited and interrogated micromechanical silicon cantilever structure

Micromechanical silicon cantilever structures of typical dimensions 1 mm x 80 micrometers x 5 micrometers have been excited by absorption of pulsed light from diode laser at 790 nm or a LED at 830 nm respectively. The excitation motion of the cantilevers was measured by means of a fiber-optic Michelson interferometer as well as a reflective multimode fiber optic pick up. In addition to the optical signal the electrical signal of a thin film piezoresistive transducer localized at the base of the cantilever has been measured. The optimal fiber position with respect to the cantilever was determined experimentally. At this position a signal to noise ratio of about 6 could be realized for the detected signal at 5 kHz bandwidth for optical power levels of 56 micrometers. Using a 125 micrometers diameter optical fiber this corresponds to an optical power density of 4.6 mW/square millimeters which is below the critical value of 5 mW/square millimeters suggested for explosive environments

Streckenneutrale faseroptische Sensorkonzepte, insbesondere auf Basis des Faser-Fabry-Perot-Interferometers Abschlussbericht

One of the barriers for the introduction of fiber optic sensors (FOS) into the market is insufficient transmission line neutrality, i.e. independence of the measurement on perturbations on the fiber line. Transmission line neutrality is a necessary condition for the development of sensor networks (bus compatibility). The main goal of the project was therefore the development of transmission line neutral FOS-concepts, starting from work on fiber-Fabry-Perot (FFP) Interferometry. Apart from this monomode sensor concept with optical phase encoding three multimode concepts with intensity, HF-modulating phase, and frequency encoding have been investigated. During the project a FFP-motility sensor, a two wavelength FFP temperature sensor, a displacement sensor with HF-modulation of the LED and with HF phase measurement, a frequency encoded gas density sensor with micromechanical silicon resonator as well as a OTDR-operated network have been developed. The motility sensor has been successfully subjected to clinical tests, and the displacement sensor has been transferred into a small size industrial company. (orig.)Eine wesentliche Barriere fuer die Markteinfuehrung faseroptischer Sensoren (FOS) besteht in der mangelnden Streckenneutralitaet, d.h. Unabhaengigkeit der Messung von Stoerungen auf der Faserstrecke. Diese Streckenneutralitaet ist notwendige Voraussetzung zum Aufbau von Sensornetzwerken (Buskompatibilitaet). Wichtigstes Ziel des Vorhabens war deshalb die Entwicklung und Untersuchung streckenneutraler FOS-Konzepte, ausgehend von Arbeiten zur Faser-Fabry-Perot (FFP)-Interferometrie. Neben diesem monomodigen Sensorkonzepten mit Kodierung in die optische Phase wurden drei multimodige Konzepte mit Kodierung in die HF-Modulationsphase, Frequenzkodierung und Intensitaetskodierung untersucht. Die Arbeiten fuehrten zur Entwicklung eines FFP-Motilitaetssensors sowie eines Zwei-Wellenlaengen-FFP-Temperatursensors, eines Wegsensors mit HF-Modulation der Leuchtdiode und HF-Phasenmessung, eines frequenzkodierten Gasdichtesensors mit mikromechanischem Resonator aus Silizium und eines OTDR-betriebenen Netzwerkes aus einfachen intensitaetskodierten Sensoren mit zeitverzoegerter Referenz. Der Motilitaetssensor wurde in ersten klinischen Tests erfolgreich erprobt, der Wegsensor in ein mittelstaendisches Unternehmen transferiert. (orig.)Available from TIB Hannover: FR 6908+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

The XRCC3 Thr241Met polymorphism and breast cancer risk: A case - Control study in a Thai population

The X-ray repair cross-complementing group 3 gene (XRCC3) belongs to a family of genes responsible for repairing DNA double-strand breaks caused by normal metabolic processes and exposure to ionizing radiation. Polymorphisms in DNA repair genes may alter an individual's capacity to repair damaged DNA and may lead to genetic instability and contribute to malignant transformation.We examined the role of a polymorphism in the XRCC3 gene (rs861529; codon 241: threonine to methionine change) in determining breast cancer risk in Thai women. The study population consisted of 507 breast cancer cases and 425 healthy women. The polymorphism was analysed by fluorescence-based melting curve analysis. The XRCC3 241Met allele was found to be uncommon in the Thai population (frequency 0.07 among cases and 0.05 among controls). Odds ratios (OR) adjusted for age, body mass index, age at menarche, family history of breast cancer, menopausal status, reproduction parameters, use of contraceptives, tobacco smoking, involuntary tobacco smoking, alcohol drinking, and education were calculated for the entire population as well as for pre- and postmenopausal women. There was a significant association between 241Met carrier status and breast cancer risk (OR 1.58, 95% confidence interval (CI) 1.02-2.44). Among postmenopausal women, a slightly higher OR (1.82, 95% CI 0.95-3.51) was found than among premenopausal women (OR 1.48, 95% CI 0.82-2.69). Our findings suggest that the XRCC3 Thr241Met polymorphism is likely to play a modifying role in the individual susceptibility to breast cancer among Thai women as already shown for women of European ancestry

Entwicklung integriert-optischer Gassensoren Abschlussbericht

Based on integrated optical transducers, new types of gas sensors were developed. The transducers used are different types of interferometer, grid couplers and adsorption sections. Gas-sensitive coatings were developed and were intensively examined regarding sensitivity, cross-sensitivity and long-term stability. Sensors for CO_2, NH_3 and solvent vapours can be produced in this way. (orig)Auf der Basis integriert-optischer Transducer wurden neuartige Gassensoren entwickelt. Die verwendeten Transducer sind verschiedene Interferometertypen, Gitterkoppler und Absorptionsstrecken. Gassensitive Beschichtungen wurden entwickelt und hinsichtlich Empfindlichkeit, Querempfindlichkeiten und Langzeitstabilitaet intensiv untersucht. Sensoren fuer CO_2, NH_3 und Loesemitteldaempfe sind auf diesem Wege realisierbar. (orig.)Available from TIB Hannover: F94B0324 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Phase II study of satraplatin and prednisone in patients with metastatic castration-resistant prostate cancer: A pharmacogenetic assessment of outcome and toxicity

Genetic polymorphisms in DNA repair enzymes (excision repair cross-complementing group 1 [ERCC1] and x-ray cross-complementing group 1 [XRCC1]) may predict treatment outcome and response to platinum-based treatment. Twenty-four patients were enrolled in this single-arm study to assess the association between ERCC1 and XRCC1 gene variants and treatment outcomes with satraplatin in patients with docetaxel-refractory metastatic castration-resistant prostate cancer. BACKGROUND: We assessed the effect of excision repair cross-complementing group 1 (ERCC1) and x-ray cross-complementing group 1 (XRCC1) gene polymorphisms on treatment outcomes with satraplatin and prednisone in patients with metastatic castration-resistant prostate cancer previously treated with docetaxel-based therapy. PATIENTS AND METHODS: Twenty-four patients were enrolled in this single arm study. The primary objective was to determine if the presence of ERCC1 Asn118Asn (N118N, 500C>T, rs11615) and XRCC1 Arg399Gln (R399Q, 1301G>A, rs25487) genetic variants might be associated with an impact on progression-free survival (PFS); secondary objectives included overall response, survival, and toxicity. RESULTS: After population stratification by race, white patients carrying heterozygous or variant genotypes at the ERCC1 C>T locus had a >3-fold longer median PFS (5.8 vs. 1.8 months; 2P = .18, adjusted) and 5-fold longer median overall survival (OS) (15.7 vs. 3.2 months; 2P = .010, adjusted) than did patients carrying only wild-type alleles. For the XRCC1 G>A variant, without regard to race, patients carrying the wild-type GG alleles had a longer PFS (9.3 months) than those carrying GA or AA alleles (2.7 months; 2P = .02). Similarly, those carrying GG alleles did not reach median OS, whereas those carrying GA or AA alleles had a median OS of 9.6 months (2P = .12, adjusted). Multivariable analysis by using Cox proportional hazards modeling demonstrated that only XRCC1 was associated with PFS. CONCLUSIONS: To our knowledge, this is the first prospective study to date in patients with metastatic castration-resistant prostate cancer that describes predictive germline polymorphisms of ERCC1 and XRCC1 for assessing the clinical activity of satraplatin