[en] An extension of anharmonic frequency analysis (AFA) is used to analyze and extrapolate the sunspot numbers. The higher resolution possible with this new approach in principle permits a better accuracy of the prediction for a given extrapolation range, provided the time series is stationary. The results indicate that the extremas of the sunspot numbers of the next three solar cycles will not exceed a magnitude of 100 significantly

No abstract available

[en] F region parameters can change by relatively large amounts over short periods of time under so-called undisturbed conditions. There is evidence that these changes are due to propagating acoustic gravity waves. While the periods of these variations and other local parameters can be measured with a high-resolution digital ionosonde, other quantities like wavelength or magnitude and direction of the propagation velocity cannot be observed. The Clarke Lake radio astronomical antenna array which can be operated in the HF band allows tracking the motion of medium scale (100-500 km) disturbances by observation of the changes in the apparent position of radio stars. Some first data samples were recorded and analyzed

[en] Platelet-activating factor (PAF) is a proinflammatory lipid that has platelet-stimulating property. PAF receptor-coupled activation of phosphoinositide-specific phospholipase C (PLC) and phosphorylation of several proteins has already been established in our laboratory. To investigate further the molecular mechanism and relationship between activation of PLC and protein phosphorylation, we have used Genistein (a putative inhibitor of tyrosine-specific protein kinases), phosphotyrosine antibody, and phosphoamino acid analysis to probe the involvement of tyrosine kinase in this process. Washed rabbit platelets were loaded with myo-[2-3H]inositol and challenged with PAF (100 nM) after pretreatment with Genistein. PLC-mediated production of radioactive inositol monophosphate, inositol diphosphate, and inositol triphosphate was monitored. PAF alone caused stimulation of PLC activity [( 3H]inositol triphosphate production), whereas pretreatment with Genistein (0.5 mM) diminished PAF-stimulated PLC activity to basal level. Genistein also blocked PAF-stimulated platelet aggregation at this dose. In contrast to Genistein, staurosporine which inhibits protein kinase C, potentiated PAF-stimulated [3H]inositol triphosphate production. Genistein substantially inhibited the combined effects of staurosporine and PAF on inositol triphosphate production. Genistein also reduced PAF-induced phosphorylation of Mr 20,000 and 50,000 proteins. Phorbol 12-myristate 13-acetate-induced Mr 40,000 protein phosphorylation was also affected by Genistein. The above results suggested that Genistein inhibited tyrosine kinase at an early stage of signal transduction by inhibiting PLC. This, in turn, decreased the activation of protein kinase C and, therefore, caused a reduction in Mr 40,000 protein phosphorylation

[en] The analysis of digital ionograms taken in short-time intervals shows rapid changes of sporadic E parameters. This is directly visible in the variation of the top frequency or maximum electron density of such layers. Angle of arrival data which were available with those ionograms also showed fast changes of the apparent direction and often large deviations from vertical propagation. 5 refs

[en] Data collected during 1980/1981 at Brighton, Colorado show clearly that the F region variations are undersampled in space and time by standard recording procedures. Fast temporal changes with periods as short as 10 min are directly observable if ionograms are taken in rapid sequences of at least 12 ionograms per hour. In order to obtain a correct spatial sampling, the distances between observing stations should not be much larger than 100 km. This conclusion is derived from the temporal variations of F layer parameters assuming a propagation velocity typical for acoustic gravity waves. 5 refs

[en] The chromate reducing actinomycetes, Arthrobacter sp. SUK 1205, isolated from chromite mine overburden of Odisha, India exhibited significant chromate reduction during growth with characteristic formation of pale green insoluble precipitate. Reduction of chromate increased with increase in inoculum density but the reduction potential declined as and when Cr(VI) concentration in the medium was increased. Chromate reducing efficiency was promoted when glycerol and glucose were used as electron donors and pH and temperature were maintained at 7.0 and 35 degree C, respectively. The reduction process was inhibited by several metal ions and metabolic inhibitors but not by Cu(II), Mn(II) and DNP. Among the matrices tested for whole cell immobilization, Ca-alginate immobilized whole cells were found to be most effective and were comparable with non-immobilized cells. Minimal salts (MS) medium was the most effective base for Cr(VI) reduction studies with immobilized cells. Under such conditions, the immobilized cells retained their enzymatic activity at least for 4 consecutive cycles indicating the potential of Arthrobacter sp. SUK 1205 in bioremediation of environmental chromium pollution. (author)

[en] Electron density profiles from nine daytime rocket flights at Wallops Island, Va., conducted by the University of Illinois at high and low levels of solar activity, are compared with profiles calculated by inversion of ionograms obtained at the same times and location. Sources of error and uncertainty in the ionogram inversion are discussed, as are means for their amelioration. In most cases, agreement between the two kinds of measurement within a few percent in electron density and within a few percent of a scale height can be achieved. (auth)

[en] Full text: Radioiodine is being increasingly used in the treatment of hyperthyroidism. The primary reasons for choosing radioiodine therapy are its effectiveness, ease of administration, relatively low cost and paucity of side effects. Here we presented our experiences and outcome of radioiodine therapy in hyperthyroidism in a divisional referral centre.We retrospectively analyzed 203 patients receiving radioiodine therapy for hyperthyroidism in Centre for Nuclear Medicine and Ultrasound, Khulna during the period from July 1994 to June 2004. All the patients had clinical signs and symptoms of hyperthyroidism as well as elevated triiodothyronine (T₃), thyroxine (T₄) and suppressed thyroid stimulating hormone (TSH). T₃, T₄ and TSH were done in all cases. Radionuclide scan and ultrasound of thyroid gland, radioactive iodine uptake (RAIU), thyroid microsomal antibody (TMAb) and fine needle aspiration cytology (FNAC) was done in selected cases. We assessed all patients prior to radioiodine therapy. Elderly patients and all those with cardiac complications and severe hyperthyroidism were pretreated with a short course of antithyroid drug in full dosages until they were clinically and biochemically euthyroid. Ninety five patients were on antithyroid medication (Neomercazole) prior to radioiodine therapy. Antithyroid medication were stopped 3 days before radioiodine therapy and restarted 3 days later and continued for 1 to 2 months depending on patient's symptoms. The rest of the patients received either no treatment or beta-blocker prior to radioiodine therapy. Menstrual history was taken in female patients and pregnancy was excluded by ultrasonography in doubtful cases before administering radioiodine. The likely consequences of the treatment were fully explained to the patients and attendants, the usual precautions for radiation protection of the public and the necessity of the follow-up were discussed and verbal consent was taken before administering radioiodine. Radioiodine was given orally as Na ¹³¹I solution to all patients in modified fixed dose regime ranged from 5 mCi to 15 mCi. All the patients were advised to attend the centre if any complications arise and in regular follow up at 6 weeks, 3 months, 6 months, 9 months and 1 year and then annually. Clinical and biochemical evaluations were done in follow up visit. If the first dose was found to be ineffective in controlling the disease or hyperthyroidism persist, then the second dose, third dose or fourth dose was given after 6 months interval with proper clinical and biochemical evaluation. If even with fourth dose, hyperthyroidism was not controlled, the case was referred for surgical management. The amount of radioiodine given in the second dose and in subsequent third dose or fourth dose was same as first dose or higher. Early complications of radioiodine were only encountered when the patient attended the centre for such. During follow up, patients were classified as cured if the functional status was either euthyroid or hypothyroid within 1 year without further treatment of hyperthyroidism by antithyroid drugs or radioiodine. Patient was diagnosed as hypothyroid on the basis of clinical and biochemical criteria, including low T₄ and high TSH. Total 203 patients with hyperthyroidism treated with radioiodine were studied. Among 203, 117 were female and 86 were male with female male ratio of 1.4:1. The mean age of the patients was 38.38 10.42 years (ranged 16 years to 70 years). Among 203 cases, 190 (172 Graves' diseases, 8 solitary toxic nodule, 10 toxic multinodular goiter) patients attended regularly as per advice and 13 patients were lost to follow up. It was found that 18 patients became euthyroid within 3 months, 35 patients became euthyroid within 6 months, 19 patients became euthyroid within 9 months and 97 patients became euthyroid within 1 year. Thus the cure rate was found to be 88.95% (169/190). In 18 (9.47%) cases hyperthyroidism persisted with no clinical and biochemical improvement within 6 months in which 15 were Graves' disease, 1 solitary toxic nodule and 2 toxic multinodular goiter. After becoming euthyroidism, hyperthyroidism recurs in 3 (1.58 %) cases within 1 year. Recurrence of hyperthyroidism was also seen in 2 cases after 1 year of radioiodine treatment. These patients (persistent and recur cases) were treated with second dose and if needed third and/or fourth dose of radioiodine. Second dose was given in 23 cases, third dose given in 7 cases and fourth dose given in 2 cases. We referred 1 case for surgical treatment not for responding even with fourth dose of radioiodine. During our follow up period, 6 patients became hypothyroid within 3 months, 14 patients became hypothyroid within 6 months, 7 patients became hypothyroid within 9 months and 5 patients became hypothyroid within 1 year. Thus hypothyroidism within 1 year was found to be 16.84% (32/190). Other side effects such as iododerma were observed in 5 (2.63%) cases, radiation thyroiditis developed in 17 (8.95%) cases, thyroid storm developed in 2 (1.05%) cases. Out of 43 with ophthalmopathy, 2 (4.44%) deteriorated, 1 (2.32%) unchanged and the rest (93.02%) improved. New ophthalmopathy developed in 3 cases (3/147 i.e., 2.04%). None developed any malignancy or leukemia during our follow up period. We conclude that our experience revealed similar outcomes as have been reported by other workers with the exception of iododerma, one of the early complications of radioiodine therapy that we noticed during our follow up period. (author)

[en] Most of the information about the near-earth's environment up to the height of the F region maximum is obtained by ionosondes. The height range in question is below the altitude of long-lasting satellites. In addition, satellite measurements cannot provide the temporal and spatial resolution for an unambiguous sampling of the dynamic phenomena of the ionosphere, unless a large number of satellites with identical equipment is placed in proper orbits. Similar remarks apply to balloon and rocket observations. The advance of digital ionosondes permits the measurement of new quantities (for example, echo phase) and of classical parameters (for example, delay time and signal strength of an echo) with much improved precision. The analysis of such data in turn provides more details and higher accuracy of properties of the ionosphere. This will be demonstrated here for electron density profile parameters, Doppler frequencies, angle of arrival measurements, and other quantities. 4 refs