An investigation of the temperature dependency of the relative population inversion and the gain in EDFAs by the modified rate equations

The dependence of the relative population inversion in Er3+-doped fiber amplifiers (EDFAs) upon temperature and cross sections, taking into account the amplified spontaneous emission (ASE), are investigated theoretically by the modified rate equation model for 980 nm and 1470 nm pumping conditions. For the temperature range from 0 to +50 oC and at the different signal wavelengths, the temperature and cross section dependent gain characteristics with respect to pump powers are also examined in detail for the both conditions. As a consequence, the dependence of the performance of EDFAs on temperature for 980 nm pumping is weaker than that for 1470 nm pumping, not only at room temperature but also at the temperature range of 0 to +50 oC. However, the performance of EDFAs is more efficient at the pumping wavelength of 1470 nm than that of 980 nm for a wide range of temperature and high-pump powers. The results of this theoretical model are a good agreement with the experimental ones in the literature.Comment: 17 pages, 6 figures. submitted to Optics Communication

Analysis of cerebrospinal fluid from cattle with central nervous system disorders after storage for 24 hours with autologous serum

BACKGROUND: We compared the changes in cell morphology, total and differential cell counts between cerebrospinal fluid (CSF) samples analyzed within an hour of collection (fresh sample) and after the addition of autologous serum and storage for 24 h (stored sample) in 27 cattle with central nervous system disorders. RESULTS: There was a positive linear correlation between total and differential cell counts in the fresh and the stored samples. Cell morphology was preserved in all stored samples, except for increased vacuolization of mononuclear cells and cleaved nuclei of some small mononuclear cells. In the stored CSF samples, the total nucleated cell count and monocyte percentage were decreased (P = 0.01; P = 0.03), while the lymphocyte percentage was increased (P = 0.04). Mononuclear pleocytosis diagnosed in 20 fresh samples was cytologically confirmed in 12 of the 20 stored samples. In the remaining eight stored samples, the number of total nucleated cells was within the normal range. Neutrophilic pleocytosis was confirmed in all seven stored samples. The overall agreement rate between cytologic interpretation of the fresh and the stored CSF samples was 70 % (100 % for neutrophilic pleocytosis and 60 % for mononuclear pleocytosis). CONCLUSIONS: Adding 11 % of autologous serum to CSF samples might allow delayed analysis with a good agreement rate for CSF cytological interpretation. Caution is nonetheless warranted, as animal age, anamnesis, and neurological presentation need to be considered when interpreting stored CSF without pleocytosis. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12917-015-0502-x) contains supplementary material, which is available to authorized users

Atomic Dipole Traps with Amplified Spontaneous Emission: A Proposal

We propose what we believe to be a novel type of optical source for ultra-cold atomic Far Off-Resonance optical-dipole Traps (FORTs). The source is based on an Erbium Amplified Spontaneous Emission (ASE) source that seeds a high power Erbium Doped Fiber Amplifier (EDFA). The main interest of this source is its very low coherence length, thus allowing an incoherent superposition of several trapping beams without any optical interference. The behavior of the superimposed beams is then a scalar sum greatly simplifying complex configurations. As an illustration, we report an estimation of the intensity noise of this source and an estimation of the atomic excess heating rate for an evaporative cooling experiment application. They are both found to be suitable for cold atoms experiments

Thermal stability and spectroscopic properties of erbium-doped niobic-tungsten-tellurite glasses for laser and amplifier devices

Er3+ doped niobic-tungsten-tellurite glasses doped with concentration of Er3+ ion up to 3 wt% were fabricated. The effect of Er3+ doping concentration on thermal stability and optical properties was investigated in order to obtain the most suitable rare earth content for developing 1.5 micron compact fiber amplifier pumped with a commercial telecom 980 nm laser diode. The maximum doping concentration allowed was found to be around 1.77 x 10^20 ions/cm^3, for which a broad 1.5 micron emission spectra of 65 nm FWHM and a lifetime of 3.4 ms for the 4I13/2 level was measure

Lxs fantasmas de mi placard

El presente proyecto final tiene como objetivo la presentación de manera escrita del trabajo de graduación correspondiente al cortometraje Lxs fantasmas de mi placard. Dentro de este proyecto se encuentran especificaciones en cuanto al contexto geográfico y temporal y el proceso de grabación, como así también sobre el proceso de creación y motivación que llevaron a la realización del mismo.Tesis en co-autoría con Aldana Agustina Arrative (ver "Documentos relacionados").Facultad de Arte

L’intelligenza artificiale in movimento. L’impatto sui diritti costituzionali della smart mobility

L’intero comparto della mobilità sta vivendo una rivoluzione: il cambiamento, che ha già visto, in una prima fase, l’introduzione della guida assistita, porterà, in tempi non troppo lunghi, alla vera e propria sostituzione dell’intelligenza artificiale all’uomo nella guida, di modo che tutti i mezzi di trasporto saranno totalmente autonomi, ossia capaci di condursi da soli. Muovendo dalle trasformazioni in essere e dalla loro attuale regolazione a livello normativo, il volume indaga i rapporti tra diritti e tecnologia, ricostruendo specificamente l’impatto del fenomeno della smart mobility sui diritti e sulle libertà costituzionali, in termini di maggiori o minori opportunità di godimento di essi