42,935 research outputs found
Mid-infrared spectroscopy of Nd:YLF crystal
No full textAlthough well known for its near infrared emission, Nd:YLF is far less studied in the mid-infrared range (MIR). In this work, the polarized stimulated emission cross section of the decay to the I-4(15/2), at around 2 mu m and the branching ratios of all the radiative decay channels from F-4(3/2) to the lower levels, have been estimated by applying the beta-tau method. Moreover, the absorption of Nd:YLF crystal has been measured from the near infrared up to the crystal absorption edge of the spectrum in MIR. Finally, the emission from the first excited state to the sublevels of the ground state in mid infrared at around 4.9 and 5.9 mu m have been observed and discussed
L’impatto della valutazione in termini di cambiamento organizzativo : riflessioni sul metodo di ricerca applicato al caso di tre università
No full textNasal packing in sphenopalatine artery bleeding: therapeutic or harmful?
No full textThe aim of this study is to present our management protocol of sphenopalatine artery bleeding, demonstrating that nasoendoscopic cautery (NC) was a more effective method than the nasal packing, in terms of shorter inpatient stay and reduced complications rate. We present ten posterior epistaxis not resolved by nasal packing. Tabotamp® was placed in the area of sphenopalatine foramen and/or in those parts of the posterior nasal cavity, where it was suspected that bleeding origins. In two cases, the bleeding was resolved in this way, instead eight cases needed of subperiosteal cauterization of sphenopalatine artery by Dessi bipolar forceps (MicroFrance®). 4 of these 8 patients evidenced a remarkable bleeding removing nasal packing (Hb before-nasal packing = 15 ± 0.69 versus Hb after-nasal packing = 13.3 ± 0.81; t student = 2.94; p value = 0.025). These four patients showed a deviation of the nasal septum ipsilateral to epistaxis, and according our experience, a traumatism of sphenopalatine area can be caused by Merocel® nasal packing in this condition. During follow-up, no recurrences of nasal bleeding have been observed in such patients. Nasal packing must be considered if posterior epistaxis is severe, but always taking into account the specific anatomy of patient and in particular septal spurs that can further compromise sphenopalatine artery. In our experience, the endoscopic endonasal cauterization of the sphenopalatine branches represented a safe and effective procedure.
Sliding time windows assessment of storage systems capability for providing ancillary services to transmission and distribution grids
No full textThe continuous increase of Renewable Energy Sources (RESs) connected to distribution networks requires a careful review of the current regulatory framework to enable the provision of Ancillary Services (ASs) by these small-scale units. One of the envisaged options for coordinating Transmission System Operators (TSOs) and Distribution System Operators (DSOs) is the agreement and regulation of a scheduled power profile at the Primary Substation (PS). This means assigning the balancing responsibility to DSOs and, consequently, reducing the unpredictability of the power exchanges with the upstream transmission grid. The paper proposes a novel procedure for the management of Distributed Energy Storages (DESs) in order to provide ASs to both the DSO (local regulation of distribution network and congestion management) and the TSO (control of the power profile at the PS). The methodology, based on a sliding time window approach, evaluates the actual availability of each storage unit in providing ASs, assigns a scheduled profile and corrects it during the real-time operation. In addition, for each DES, the scheduled State of Charge (SoC) is restored in accordance with network constraints. Simulations on a realistic case study network are carried out considering randomly perturbed power profiles for both loads and generators. Benefits associated with storage coordination (power exchange management at the PS and support to DSO in voltage regulation and congestion resolution) are evaluated and discussed
Effect of testicle postmortem storage on goat frozen-thawed epididymal sperm quality as a tool to improve genebanking in local breeds
No full textThe interest to develop assisted reproductive technologies and cryobanking for farm animal genetic resource conservation has recently increased. However, cryopreservation for ex-situ management of genetic diversity sometimes is not routinely feasible, owing to the lack of facilities (AI centres, laboratories) and expertise near the local breed farming area. In these cases, epididymal sperm obtained from slaughtered or castrated animals, associated with the possibility of managing rather long periods between animal death, sperm recovery and freezing, would increase the opportunities to create semen storages. This investigation addresses the pre-freeze/post-thaw quality of goat epididymal sperm as a function of testicle storage temperature (environment or +5°C) and time elapsed between animal's death and sperm recovery (0, 24, 48, 72 h) to establish the optimal protocols for the recovery and cryopreservation of epididymal sperm in this species. Testicles of 50 mature bucks collected at the abattoir were divided in two groups: half of the testicles (n=50) were transported to the laboratory at environment temperature (E), whereas the remaining half (n=50) at a refrigeration temperature (R) of +5°C. In the two groups (E) and (R), one testicle from each pair was processed after slaughter forming the time 0 groups (0E and 0R). The contralateral testicle was processed after 24, 48 or 72 h of storage, at the corresponding temperature. Sperm motility and kinetic parameters, viability and morphology were assessed in pre-freeze and post-thaw samples. Until 48 h postmortem, both E and R temperatures are able to maintain good pre-freeze epididymal sperm quality. After 48 h postmortem, R temperature is fundamental to reduce epididymal sperm quality decay in pre-freeze samples. Moreover, testicle refrigeration also has a positive impact on post-thaw samples, allowing a lower decline through time considering total motility, kinetics parameters, sperm viability and sperm abnormalities. Therefore, when sperm cryopreservation is not immediately practicable, goat testicles should be transported and stored at 5°C up to a maximum of 48 h postmortem to ensure an acceptable sperm quality
Erratum to: Effect of moderate red wine intake on cardiac prognosis after recent acute myocardial infarction of subjects with Type 2 diabetes mellitus (Diabetic Medicine, (2006), 23, 9, (974-981), 10.1111/j.1464-5491.2006.01886.x)
No full textIn an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola.In an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola
Centralized OPF in Unbalanced Multi-Phase Neutral Equipped Distribution Networks Hosting ZIP Loads
No full textA novel methodology for the management of distribution network based on neutral losses allocation factors
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