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Abstract  

The 11 th CITES Conference in 2000 decided to maintain a total worldwide ban on trade of elephant ivory. The 12 th Conference in 2002 decided to allow a conditional trade in stockpiled ivory in 2004. Reopening of the ivory trade would require methods to identify the origin of the ivory so that legal ivory can be distinguished from the black-market ones. In this study, we describe the X-ray fluorescence multi-element analysis of ivory samples from various regions of Africa and Southeast-Asia to characterize ivory of the various elephant populations.

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Abstract  

66 archaic Greek silver coins have been analyzed for the minor elements Cu, Au, Bi and Pb, and for the trace elements Na, Mn, Co, Ni, As, Sn, Sb and Ir. Instrumental neutron activation has been used for the determination of Cu and Au and atomic absorption spectroscopy for Pb and Bi. The trace elements could be detected only after a separation of the interfering matrix activities by an extraction with a diethyl-dithio-carbamate complex. The homogeneity of Au and Cu in the coins and the significance of the trace elements are discussed. The statistical evaluation of the analytical data reveals distinct groups for coins of some provenances.

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Abstract  

A method has been developed that utilizes a special custom-made mixing device and HPLC micro liter syringe to perform mixing experiments of liquid systems directly in open measuring cells of differential scanning calorimeters. The present paper describes how to determine mixing enthalpies from time scans of the isothermal heat flux during an exothermal or endothermal process. Using ethylene glycol and the slightly volatile component water to calibrate the mixing calorimeter, the mixing enthalpy of the binary system poly(ethylene glycol) 400/water could be determined with sufficient precision compared to the results of measurements with a conventional flow calorimeter.

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Abstract  

There are a number of applications requiring measurement of the long-lived radionuclide 41 Ca at isotopic abundance, relative to 40 Ca, in the range of 10-8 to 10-16 . The long lifetime and electron-capture decay mode make radio-analytical measurements impractical and conventional mass spectrometric methods can not overcome isobaric interferences such as 41 K+ or 40 CaH+ at these levels. We approach this problem by combining laser-based resonance ionization spectroscopy with mass spectrometry. Using high-resolution single-mode lasers for resonant excitation and an intense non-resonant laser for ionization of the selectively created excited-state atoms, it is possible to essentially eliminate interference from isobars and to obtain additional optical isotopic selectivity, which can be combined with that of the mass spectrometer. Single-, double-, and triple-resonance excitation schemes have been investigated experimentally and theoretically, and it is found that performance with respect to both selectivity and sensitivity increases dramatically with each additional resonance step. Thus far, triple-resonance measurements have demonstrated minimum detectable isotopic abundance of 2.5·10-13 with detection limits of ~2·105 atoms.

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Abstract  

The isotopes3He,6Li,7Be and10B exhibit extremely large cross sections, between 1 and 48 kilobarn, for (n, p) or (n, α) reactions with thermal neutrons. Together with now available extracted thermal neutron fluxes of 10( n·cm−2·sec−1 or more, these reactions present a highly sensitive method of detecting the mentioned light elements in any heavy matrix material. Through the experimentally determined energy losses of the emitted protons or α-particles, also well resolved depth profiles can be obtained, as demonstrated here for some relevant examples from semiconductor and fusion technology.

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Previously described and alternative methods of the induction of sexual maturation in the European eel were investigated. Weekly administrations of a gonadoliberin agonist (GnRH-A=D-Phe6-GnRH-Ea) did not induce statistically significant effect on the gonads of treated eels in none of the dosages used (0.1 mg and 10 mg/fish). Carp pituitary extract and carp pituitary extract together with a dopamine antagonist caused considerable external changes (increase in eye size) and significant gonadal development in two treatment groups: wild and cultivated stocks. The induction of the ovulation by double amount of CP and gonadoliberin agonist with dopamine antagonist mixture was not successful in a wild stock. Fertilisation of stripped eggs of farm eel was attempted unsuccessfully in, due to low egg quality. An advanced phase of the sexual maturation process could be induced in specimen infected by Anguillicola crassus indicating, that nematode infection is not a limiting factor in the artificial propagation of the European eel.

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Abstract  

The aim of the study reported in this paper was to derive factors describing the translocation of radiocesium from the green plant parts to the crop. Wheat, rye and potatoes were contaminated and harvested at different growth stages to allow the assessment of the contamination of the crop with known date of the radioactive deposition. At harvest, the cesium concentrations in the crop, the green plant parts (i.e., straw without ears) and the roots were measured. The results show that the contamination of the crop depends strongly on the date of134Cs application and on the type of plants. The highest translocation was observed when cesium was applied during flowering.

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Acta Veterinaria Hungarica
Authors:
T. Müller
,
T. Molnár
,
Éva Szabó
,
R. Romvári
,
Cs. Hancz
,
M. Bercsényi
, and
P. Horn

Female European eels were kept in artificial seawater for a trial period of 14 weeks. Three fish were injected intra-abdominally with carp pituitary suspension (twice a week) and human chorionic gonadotropin (every 2nd week), with the aim to induce artificial maturation. Three further fish were not treated (control). Fish were not fed during the trial. The treated fish were scanned by computed tomography (CT) every second week (the controls only at the start and at the end of the trial) to follow changes in body composition. Notable decreases were shown in total body pixel number (body volume), total body fat content, total fillet volume and fillet fat content during the experiment. Changes were more pronounced in the treated group than in the control. The abdominal volume strongly increased in the responding fish throughout the trial. The ovary volume increased measurably, while its fat content increased only until the 8th week, after which a decrease was measured. Tissue volumetric estimations of the ovary were also supported by histological results. A so-called volumetric gonadosomatic index (gonad volume/total body volume × 100) was developed for the quantitative characterisation of eel maturation.

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A comparative study of immunogenicity and efficacy of the oral rabies virus vaccine SAD P5/88 in raccoon dogs and foxes was conducted. The raccoon dogs received 10 (n = 6), 106.3 (n = 6) or 105.7 FFU SAD P5/88 (n = 5) by direct oral application, and subsequently all animals seroconverted. The foxes received 107.2 (n = 4), 106.2 (n = 4), 105.2 (n = 4) and 104.2 FFU SAD P5/88 (n = 5) by the same route. On days 106 and 196 post vaccination 10 raccoon dogs and 16 foxes were challenged with a relevant street virus, respectively. All 10 raccoon dogs vaccinated with 106.3 (n = 5) or 105.7 FFU SAD P5/88 (n = 5) survived the challenge, whereas all control animals (n = 5) died of rabies. Two foxes vaccinated with 104.2 FFU and one fox vaccinated with 105.2 FFU died of rabies on day 7, 17 and 12 post infection, respectively. Also all control foxes succumbed to rabies. Our findings demonstrate that SAD P5/88 is not only an effective vaccine for oral vaccination of foxes but also for that of raccoon dogs.

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Acta Veterinaria Hungarica
Authors:
A. Vos
,
T. Müller
,
P. Schuster
,
T. Selhorst
, and
U. Wenzel

The objective of the study was to examine possible maternally transferred antibodies (maAb) against rabies in raccoon dogs. Ten cubs born from a rabiesimmune animal were bled on days 31, 36, 43, 50, 57 and 64 post partum. The geometric mean titres of the cubs were 1.19, 1.18, 0.45, 0.25, 0.25 and 0.16 IU/ml, respectively. Up to 36 days post partum maAb were detected in all cubs at levels ≥ 0.5 IU/ml and at day 56 post partum all animals had maAb levels < 0.5 IU/ml. Based on the results of this study, it is suggested that vaccine baits should not be distributed before July if the vaccination campaign is aimed at immunizing young raccoon dogs as well.

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