A functional description of the Buffered Telemetry Demodulator (BTD)

This article gives a functional description of the buffered telemetry demodulator (BTD), which operates on recorded digital samples to extract the symbols from the received signal. The key advantages of the BTD are as follows: (1) its ability to reprocess the signal to reduce acquisition time; (2) its ability to use future information about the signal and to perform smoothing on past samples; and (3) its minimum transmission bandwidth requirement as each sub carrier harmonic is processed individually. The first application of the BTD would be the Galileo S-band contingency mission, where the signal is so weak that reprocessing to reduce the acquisition time is crucial. Moreover, in the event of employing antenna arraying with full spectrum combining, only the sub carrier harmonics need to be transmitted between sites, resulting in significant reduction in data rate transmission requirements. Software implementation of the BTD is described for various general-purpose computers

Scaling and Formulary cross sections for ion-atom impact ionization

The values of ion-atom ionization cross sections are frequently needed for many applications that utilize the propagation of fast ions through matter. When experimental data and theoretical calculations are not available, approximate formulas are frequently used. This paper briefly summarizes the most important theoretical results and approaches to cross section calculations in order to place the discussion in historical perspective and offer a concise introduction to the topic. Based on experimental data and theoretical predictions, a new fit for ionization cross sections is proposed. The range of validity and accuracy of several frequently used approximations (classical trajectory, the Born approximation, and so forth) are discussed using, as examples, the ionization cross sections of hydrogen and helium atoms by various fully stripped ions.Comment: 46 pages, 8 figure

Histopathological study of non-neoplastic lesions of nose, paransal sinuses and nasopharynx

Background: The various lesions of the nose, paranasal sinuses and nasopharynx were subjected to histopathological evaluation over a period of 5 years (2010 to 2015) at the Department of Pathology, in a rural based hospital. Total 84 specimens were studied over the time of 5 years. Methodology: The formalin fixed specimens were received with complete clinical and radiological features. Routine gross examination and required number of sections were taken and stained with hematoxylin and eosin. Result: In the study, 84 cases were of Inflammatory and Non neoplastic lesions. Nasal polyps were the most common lesions with 77 (91.67%) cases. Among the all Nasal polyps, 77 cases, 20 (25.97%) cases were of Allergic polyp, 50 (64.93%) cases were of inflammatory polyp, while 7 (9.09%) cases were of Antrochoanal polyp. 2 cases (2.38%) each of Sinusitis and Intradermal naevus. Rhinosporidiosis, Mucocele and Nasolabial cyst comprised of 1 (0.77%) case each respectively. Conclusion: In our study, most common lesions were Nasal Polyps. Most of the cases were presented in 2nd and 3rd decade of life with Male preponderance. Nasal obstruction was the most common clinical presentation in the present study

Histopathological study of non-neoplastic lesions of nose, paransal sinuses and nasopharynx

Background: The various lesions of the nose, paranasal sinuses and nasopharynx were subjected to histopathological evaluation over a period of 5 years (2010 to 2015) at the Department of Pathology, in a rural based hospital. Total 84 specimens were studied over the time of 5 years. Methodology: The formalin fixed specimens were received with complete clinical and radiological features. Routine gross examination and required number of sections were taken and stained with hematoxylin and eosin. Result: In the study, 84 cases were of Inflammatory and Non neoplastic lesions. Nasal polyps were the most common lesions with 77 (91.67%) cases. Among the all Nasal polyps, 77 cases, 20 (25.97%) cases were of Allergic polyp, 50 (64.93%) cases were of inflammatory polyp, while 7 (9.09%) cases were of Antrochoanal polyp. 2 cases (2.38%) each of Sinusitis and Intradermal naevus. Rhinosporidiosis, Mucocele and Nasolabial cyst comprised of 1 (0.77%) case each respectively. Conclusion: In our study, most common lesions were Nasal Polyps. Most of the cases were presented in 2nd and 3rd decade of life with Male preponderance. Nasal obstruction was the most common clinical presentation in the present study

Erythropoetin receptor expression in the human diabetic retina

<p>Abstract</p> <p>Background</p> <p>Recent evidence suggests erythropoietin (<it>EPO</it>) and the erythropoietin receptor (<it>EPOR</it>) may play a direct role in the pathogenesis of diabetic retinopathy. Better characterization of the <it>EPO-EPOR </it>signaling system in the ischemic retina may offer a new therapeutic modality for ischemic ophthalmic diseases. This study was performed to identify <it>EPOR </it>mRNA expression in the human diabetic eye.</p> <p>Findings</p> <p><it>EPOR </it>antisense RNA probes were validated on human pancreas tissue. In the normal eye, <it>EPOR </it>was expressed in the retinal ganglion cell layer. Minimal expression was observed in the inner and outer nuclear layer. Under conditions of diabetic retinopathy, <it>EPOR </it>expression shifted to photoreceptor cells. Increased expression was also observed in the peripheral retina.</p> <p>Conclusion</p> <p><it>EPOR </it>expression may be a biomarker or contribute to disease mechanisms in diabetic retinopathy.</p

Effects of lipoproteins on cyclo-oxygenase and lipoxygenase pathways in human platelets

The products of arachidonic acid (AA) metabolism in platelets play an important role in platelet shape change, adhesion and aggregation which may participate in the pathogenesis of ischemic heart disease and thrombosis. Since lipoproteins are also involved in the pathogenesis of thrombo-embolic disorders, the effect of human lipoproteins (HDL, LDL, VLDL) on AA metabolism in human platelets was investigated. Lipoproteins were separated by density gradient zonal ultracentrifugation. The effects of lipoproteins on production of AA metabolites in human platelets i.e., thromboxane A2 (TXA2) and hydroxy-eicosatetraenoic acids (HETEs) were examined using radiometric thin layer chromatography coupled with automated data integrator system. In human platelets, HDL inhibited 12-HETE and TXA2 formation in a concentration-dependent manner. LDL had a strong inhibitory effect on TXA2 production and a weak inhibitory effect on 12-HETE production. VLDL had no effect on platelet AA metabolism. These findings point to a new facet of lipoproteins action and suggest that lipoproteins may have a physiological role in the regulation of AA metabolism in platelets