Magneto-Optical Signature of Massless Kane Electrons in Cd_{3}As_{2}.

We report on optical reflectivity experiments performed on Cd_{3}As_{2} over a broad range of photon energies and magnetic fields. The observed response clearly indicates the presence of 3D massless charge carriers. The specific cyclotron resonance absorption in the quantum limit implies that we are probing massless Kane electrons rather than symmetry-protected 3D Dirac particles. The latter may appear at a smaller energy scale and are not directly observed in our infrared experiments.

Circannual changes in serum concentrations of thyroxine, calcitonin and parathormone in immature and mature red deer females (Cervus elaphus).

The aim of this study was to determine circannual changes in the serum concentrations of thyroxine, calcitonin and parathormone in mature and immature red deer females. Blood samples from 8 hinds were collected monthly for 26 months. Secretions of thyroxine and calcitonin showed circannual rhythms with significantly higher levels in the immature hinds compared to the mature animals (p<0.05). For thyroxine, the concentration was higher in the winter/spring period than in summer/autumn (p<0.05), while for calcitonin the concentration profile was the opposite (p<0.05). The concentration of parathormone was significantly higher in summer/autumn that in the other months of the experiment (p<0.01). These results may indicate that the hormones investigated may be involved in the regulation of seasonal reproductive activity and in processes contributing to entering puberty in red deer females.

Serum selenium concentration and glutathione peroxidase activity and selenium content in testes of Polish Konik horses from selenium--deficient area in North-Western Poland.

The aim of this study was to determine serum selenium concentrations in Polish Konik horses residing in the Odra Delta Nature Park (Poland) and to evaluate the activity of glutathione peroxidase and Se content in testes of this horse breed. In over 95% of cases, serum Se concentration was below the optimal range, and none of the horses examined was deficient in this trace element. The lack of Se deficiency in the animals examined suggests however, that the Polish Konik horses have a natural ability to the optimal use of nutrients available in their life area. Testicular content of Se and GSHPx activity in the colts was higher than those found in stallions, and a positive relationship between these antioxidants was demonstrated. The differences in Se contents and GSHPx activities in testes between colts and stallions suggest that selenoenzymes play important roles during the puberty of male horses.

The Effect of Season and Meteorological Conditions on Parasite Infection in Farm-Maintained Mouflons (Ovis aries Musimon).

Due to their limited environment, farm animals are at greater risk of parasitic infection than free-living animals, which also have greater natural resistance to parasitic diseases. The aim of the present study was to determine the influence of season and meteorological conditions (temperature and humidity) on the species composition and dynamics of parasitic infections in farmed mouflons. The study was conducted in a herd of mouflon (n = 40) in an extensive system: the animals remained on pasture all year round. The herd was dewormed twice per year with albendazole. Fecal samples were collected at monthly intervals over three years and tested. The prevalence of infection was defined based on coproscopic methods. For most of the studied protozoans (except for E. parva), a greater prevalence was recorded in spring and summer (i.w. from May to September). Regarding nematodes, Capillaria spp., Nematodirus sp., and the Trichostrongylidae demonstrated a much greater prevalence in winter (i.e., in January and December). Temperature and precipitation were found to be positively correlated with intensity of infection by protozoans. However, maximum air temperature was negatively correlated with infection intensity by some nematodes. The deworming practice used in the herd (selection of substance, date, and method of dosing) did not effectively protect the mouflons against parasitoses. Changes in the microclimate resulted in high extent and intensity of mouflon infection with gastrointestinal parasites. Understanding the dynamics of parasitic infections in mouflons during the year allows the development of an appropriate preventive programme.

Characteristics of focused soft X-ray free-electron laser beam determined by ablation of organic molecular solids.

A linear accelerator based source of coherent radiation, FLASH (Free-electron LASer in Hamburg) provides ultra-intense femtosecond radiation pulses at wavelengths from the extreme ultraviolet (XUV; lambda<100nm) to the soft X-ray (SXR; lambda<30nm) spectral regions. 25-fs pulses of 32-nm FLASH radiation were used to determine the ablation parameters of PMMA - poly (methyl methacrylate). Under these irradiation conditions the attenuation length and ablation threshold were found to be (56.9+/-7.5) nm and approximately 2 mJ*cm(-2), respectively. For a second wavelength of 21.7 nm, the PMMA ablation was utilized to image the transverse intensity distribution within the focused beam at mum resolution by a method developed here.

Analysis of Annual Changes in the Concentrations of Selected Macro- and Microelements, Thyroxine, and Testosterone in the Serum of Red Deer (Cervus elaphus) Stags.

The aim of the study was to analyze seasonal changes in the concentrations of calcium, phosphorus, magnesium, and selenium as well as thyroxine and testosterone in adult red deer stags. The highest testosterone concentrations (mean 6.29±4.36 ng/ml) were observed from the end of August to November, confirming an increase in testicular secretory activity during the mating season. The changes in thyroxine concentration show circannual rhythms, most likely related to changes in the air temperature. The highest mean level of thyroxine was observed in spring (55.69±10.99 ng/ml). The concentration of selenium also reached the highest level during this season (0.107±0.027 µg/ml). In the case of the studied macroelements, the concentrations were stable from spring to summer but then decreased to the lowest mean values in autumn in both years of the experiment (Ca, 61.17±10.60; P, 47.08±9.59; Mg, 15.96±2.39 µg/ml). The dynamics of thyroxine secretion does not seem to affect directly the metabolism of calcium, phosphorus, and magnesium. In turn, sexual activity, manifested in the increase in secretion of testosterone, may affect changes in the concentration of calcium. Additionally, we cannot exclude a connection between changes in the concentrations of testosterone and selenium.

Quantitative evaluation of the depth effect in Muehllehner's tomographic camera.

A set of computer programs written for Clincom allow the evaluation of the depth effect in Muehllehner's tomographic camera using MTFs and specificity as well as new quantites. The depth effect of the camera is compared with that of a rectilinear scanner.

[Determination of differential renal function using 99m Tc-DMSA scintigraphy]. / Problematika stanovení separované funkce ledvin pomocí scintigrafie po podání 99m Tc-DMSA.

By examination of 331 patients, using 99mTc-DMSA, the authors confirmed that static scintigraphy is an accurate method for assessment of the separate renal function. In four groups of patients with different positions of the kidneys the authors proved that correction for different absorption of gamma radiation from the left and right kidney is essential. Without correction results with a significant error are obtained, in particular in patients with an asymmetric position of the kidneys, where the results calculated without correction cannot be used for clinical purposes. The results are not influenced by the time interval between administration of the radiopharmaceutical preparation and examinations within an interval of 2 to 4 hours, with the exception of patients with severe obstructive uropathy. For assessment of the relative function of the kidneys it is better to examine the patient in a vertical position. The reproducibility of results in repeated examinations and repeated evaluation is excellent.

[Determination of differential renal function using dynamic scintigraphy]. / Problematika stanovení separované funkce ledvin pomocí dynamické scintigrafie.

By examination of 71 patients, using static and dynamic scintigraphy of the kidneys, the authors tested whether dynamic scintigraphy provides correct results of the separate renal function in case of a symmetrical localization of the kidneys. In case of slight asymmetry the error of calculation is feasible. In case of major differences in the position of the kidneys the results cannot be used for clinical purposes. In these patients static scintigraphy must be used with correction for different absorption layers.

[Antibodies against thyroxine, triiodothyronine and thyroglobulin as a possible cause of error in the diagnosis of disorders of thyroid gland function]. / Protilátky proti tyroxinu, trijodtyroninu a tyreoglobulinu jako mozná prícina omylu pri diagnostice poruch funkce stítné zlázy.

The authors examined in a 82-year-old female patient T4, T3, free T4, TSH, thyroglobulin and made the TRH-TSH functional test because of suspected thyroid disease. For thyroid hormones they obtained controversial resulting levels: in T4 signalizing an unreasonable negative value, in T3 a very high level, in TSH and the TRH-TSH test levels suggesting normal thyroid function which was consistent with the clinical picture. A more detailed laboratory analysis revealed the presence of antibodies binding 125I-T4 and 125I-T3 (radioindicators used for assessment of T4 and T3). The authors identified antibodies against T4, T3 and thyroglobulin. Their presence influenced the radioimmunoassay of T4 and T3 and also the immunoradiometric estimation of thyroglobulin (artificially raised level). The reliable result of the eufunctional condition was not influenced in the estimation of the TSH level.