Combined Effect of Dietary Cadmium and Benzo(a)pyrene on Metallothionein Induction and Apoptosis in the Liver and Kidneys of Bank Voles

Bank voles free living in a contaminated environment have been shown to be more sensitive to cadmium (Cd) toxicity than the rodents exposed to Cd under laboratory conditions. The objective of this study was to find out whether benzo(a)pyrene (BaP), a common environmental co-contaminant, increases Cd toxicity through inhibition of metallothionein (MT) synthesis—a low molecular weight protein that is considered to be primary intracellular component of the protective mechanism. For 6 weeks, the female bank voles were provided with diet containing Cd [less than 0.1 μg/g (control) and 60 μg/g dry wt.] and BaP (0, 5, and 10 μg/g dry wt.) alone or in combination. At the end of exposure period, apoptosis and analyses of MT, Cd, and zinc (Zn) in the liver and kidneys were carried out. Dietary BaP 5 μg/g did not affect but BaP 10 μg/g potentiated rather than inhibited induction of hepatic and renal MT by Cd, and diminished Cd-induced apoptosis in both organs. The hepatic and renal Zn followed a pattern similar to that of MT, attaining the highest level in the Cd + BaP 10-μg/g group. These data indicate that dietary BaP attenuates rather than exacerbates Cd toxicity in bank voles, probably by potentiating MT synthesis and increasing Zn concentration in the liver and kidneys

Hydrogen gas detection by means of a fiber optic interferometer sensor

We have developed a simple fiber optic Fabry-Perot interferometer (FPI) sensor that is used to detection and measure concentration of hydrogen gas in the air. The operating principle of the sensor is discussed in this paper, and it was noticed that the wavelength positions of the FPI reflectance peaks change with the concentration of hydrogen gas. The sensor has been successfully used to monitor concentration of H$_{2}$ in the air below Lower Explosion Limit (LEL). The sensor utilizes a layered sensing structure. This structure includes gasochromic titanium dioxide (TiO$_{2})$ sensing film. The optical H$_{2}$ gas sensor has a very short response time and a fast regeneration time at room temperature

Hydrogen detection by palladium and nickel oxide in surface acoustic wave sensor system

Przedstawiono badania nowej struktury warstwowej typu: tlenek niklu-pallad w sensorowym układzie z akustyczną falą powierzchniową pod kątem detekcji wodoru w powietrzu. Wykonano strukturę warstwową z tlenkiem niklu (NiOx) 60 nm w technologii reaktywnego rozpylania magnetronowego, pokrytą palladem o grubości 18 nm, wykonanym metodą naparowania próżniowego. Specjalnie zaprojektowany i wykonany układ elektroniczny umożliwia detekcję częstotliwości różnicowej (różnica częstotliwości toru ze strukturą warstwową oraz toru swobodnego bez pokrycia). Przeprowadzono badania oddziaływań takiej struktury z wodorem w powietrzu w zakresie średnich stężeń, nieprzekraczających wartości 2,5%. Dla stosowanej temperatury oddziaływania ok. 35°C stwierdzono maksymalną czułość struktury w zakresie stężeń wodoru pomiędzy 2 i 2,5% w powietrzu. Zmiana częstotliwości (będąca miarą oddziaływania) w tej temperaturze dla ww. stężeń wynosiła około 600 Hz.Presented are the investigations of a new layered structure: nickel oxide - palladium in a sensor system with surface acoustic wave, from the point of view of hydrogen detection in air. The layered sensor structure was prepared by means of reactive sputtering technology - nickel oxide 60 nm and vacuum deposition technology - palladium 10 nm. The specialised electronic circuit allows detection of the differential frequency (the difference between frequency with layered structure and the free ones). The investigations of such a structure with medium concentrations of hydrogen not exceeding a safety value 2.5% in air has been performed. The maximum sensitivity is detected at the interaction temperature of 35°C - the maximum change in frequency is on the level 600 Hz between 2 and 2.5% of hydrogen

Pd/V2_{2}O5_{5} fiber optic hydrogen gas sensor*

The paper presents an optical-fiber hydrogen sensor. The sensor utilizes a layered sensing structure. This structure is a layered Fabry-Perot interferometer and includes gasochromic vanadium pentoxide (V$_{2}$O$_{5})$. A structure is made at the end of multi-mode optical fiber as a sensing element. The sensor permits to detect and to measure the concentration of hydrogen in a gaseous medium. The optical H$_{2}$ gas sensor has a very short response time and a fast regeneration time at room temperature

Applications of multimode interference effects in gradient waveguides produced by ion-exchange in glass

The paper is concerned with applications of multimode interference structures (MMI) as the elements of integrated optic circuits. Investigations of MMI produced by ion-exchange in glass, obtained by visualization method of light propagation in gradient structures, using fluorescence of the substance covering the MMI section, are presented. Experimental results concern the self-imaging phenomena for symmetrical and paired interference for TE, TM and unpolarized light excitation. On the base of investigations and BPM simulations the applications of MMI are proposed

Investigations of the polyaniline and nafion bilayer sensor structure in SAW system

Presented here are the preliminary results concerning an investigations of a novel bilayer sensor structure of polyaniline and Nafion as a toxic gas sensors in a Surface Acoustic Wave system. The investigations were performed with different concentrations of the various toxic gases like SO$_{2}$, CO, H$_{2}$S and ammonia (NH$_{3}$) in synthetic dry air. The prototype polyaniline and nafion bilayer structure has been manufactured by two deposition technologies: 180 nm of PANI by PVD technology and thin Nafion film by spin coating technology and specific process of annealing. A good interaction with various concentrations of ammonia for the bilayer structure (PANI film with Nafion) has been observed

Studies of changes in electrical resistance of zinc oxide nanostructures under the influence of variable gaseous environments

The paper deals with the investigations concerning the influence of the changing gas environment on electrical resistance of zinc oxide (ZnO) nanostructures. The investigated structures are wide-gap semiconductors with the morphology of ZnO flower-shaped agglomerates of nanostructures. The resistance changes of these nanostructures were tested under the influence of various gases such as nitrogen dioxide (NO2), hydrogen (H2), ammonia (NH3) and also of humidity changes of carrier gases. To clarify the mechanisms of physicochemical processes in ZnO nanostructures during their interaction with gaseous environments, investigations were performed in two different carrier gases, viz. in synthetic air and in nitrogen. The study was carried out at a structure temperature of 200◦C

Studies of changes in electrical resistance of zinc oxide nanostructures under the influence of variable gaseous environments

The paper deals with the investigations concerning the influence of the changing gas environment on electrical resistance of zinc oxide (ZnO) nanostructures. The investigated structures are wide-gap semiconductors with the morphology of ZnO flower-shaped agglomerates of nanostructures. The resistance changes of these nanostructures were tested under the influence of various gases such as nitrogen dioxide (NO2), hydrogen (H2), ammonia (NH3) and also of humidity changes of carrier gases. To clarify the mechanisms of physicochemical processes in ZnO nanostructures during their interaction with gaseous environments, investigations were performed in two different carrier gases, viz. in synthetic air and in nitrogen. The study was carried out at a structure temperature of 200◦C