102,487 research outputs found
Cylindrical resonator filled with four alternating sectors of DPS and DNG materials
No full textA circular cylindrical metallic resonator with four alternating sectors of DPS and DNG materials is analyzed, in the frequency domain. The two materials are linear, lossless, homogeneous, and anti-isorefractive to each other. The electric field is assumed to be parallel to the cylinder axis. It is also shown that the resonator's dispersion relation is always satisfied for particular geometries. Numerical results for several sectors' combinations will be presented and discussed at the conferenc
Cylindrical Resonator Sectorally Filled With DNG Metamaterial and Excited by a Line Source
No full textA circular cylindrical resonator with metallic walls is analyzed in the phasor domain. The resonator contains a wedge of double-negative (DNG) metamaterial that is anti-isorefractive to the double-positive (DPS) material filling the remaining volume of the resonator, and whose edge is located on the resonator axis. The resonance conditions are established. The problem of an electric line source parallel to the axis and located anywhere inside the DPS region is solved exactly. Numerical results are presented and discusse
Efecto de la sal de estradiol, estatus ovárico y condición corporal sobre el porcentaje de preñez en vacas con cría IATF
No full textArmendano, J.I.; González Chaves, S.; Uslenghi, G.; Cabodevila, J.; Callejas, S.S.: Efecto de la sal de estradiol, estatus ovárico y condición corporal sobre el porcentaje de preñez en vacas con cría IATF. Rev. vet. 26: 2, 108-112, 2015
Isorefractive wedge
No full textThe problem of diffraction by an isorefractive wedge of arbitrary angle is solved with the method of separation of variables in the frequency domain, when the incident field is either a plane wave propagating in a direction perpendicular to the edge of the wedge or a line source parallel to the edge. The dispersion relation is derived, and is solved explicitly for certain wedge angles that are commensurable to Pi greco radians. The modal expansion coefficients in the eigenfunction series solutions for the electromagnetic field components are determined as residues of suitable meromorphic function
Le anomalie dell'arteria epatica in relazione alla chirurgia dell'ipertensione portale
No full textThis study was aimed at investigating the occurrence of hepatic artery variants, at comparing the diagnostic value of duplex Doppler US with that of angiography, and at correlating the results with the technical problems in portal hypertension surgery. All patients were studied with angiography, conventional and duplex Doppler US. In 162 patients with portal hypertension, 38 hepatic artery variants (23.4%) were observed and classified according to Michaels. The commonest variant recognized by angiography was right hepatic artery arising from superior mesenteric artery (type III according to Michaels). US demonstrated hepatic artery variants in 9/162 patients (5.5%). At surgery, variants were found in 3/162 subjects (1.8%) and caused surgical problems in 2 of them (1.2%) - i.e., right hepatic artery arising from superior mesenteric artery. Arteriography is still the best examination to depict hepatic artery variants, while duplex Doppler US demonstrates only a few types. Moreover, the number of variants detected by imaging techniques (23.4%) differs greatly from that observed at surgery (1.8%). Finally, hepatic artery variants are not correlated with surgical problems, nor can the latter be foreseen by imaging methods. US is useful but not essential to detect hepatic artery variants which are subsequently confirmed by angiography
Coronary stenting after unsuccessful emergency angioplasty in acute myocardial infarction: results in a series of consecutive patients.
No full textNineteen consecutive procedures of coronary stenting were attempted in 70 consecutive patients (27\%) with evolving myocardial infarction due to threatened vessel reocclusion after primary (16 cases) or rescue (3 cases) angioplasty. Two patients were in cardiogenic shock. Stent delivery was successful in 18 patients, with a Thrombolysis in Myocardial infarction flow grade 3; residual diameter stenosis and minimum luminal diameter were 19\% +/- 11\% and 2.96 +/- 0.62 mm, respectively. After the procedure, heparin was continued for 4 days and 250 mg ticlopidine twice a day for 1 month. Acute stent occlusion occurred in one patient 1 hour after the procedure and was successfully treated with emergency repeat angioplasty. Subacute stent occlusion occurred 6 days after the procedure in one patient, with multivessel coronary disease and a suboptimal stent result. He had been referred for surgery, and emergent coronary artery bypass was performed. Coronary bypass surgery was performed in another patient before discharge because of severe multivessel disease. Persistent cardiogenic shock and new myocardial infarction in another location were the causes of death in two patients, 3 and 10 days after the procedure, respectively. Fifteen patients were discharged with a patient infarct vessel and without reinfarction or need for coronary bypass surgery. One patient had repeat angioplasty for intrastent restenosis at 3 months. The remaining 14 patients were free from new coronary events 4 +/- 2 months after the procedure. Although acute myocardial infarction is generally considered a contraindication to the use of coronary stents, stents may play a role in increasing the rates of successful infarct artery reperfusion
Estrusioni ortodontiche settoriali per la stabilizzazione post-riduttiva di un caso di lussazione temporo-mandibolare
No full textDiffuse cystic lung diseases : correlation between radiologic and functional status
No full textBACKGROUND: High-resolution CT (HRCT) scanning plays an important role in the diagnosis of diffuse cystic lung diseases (DCLDs). However, its role in the clinical evaluation of patients affected by DCLD has not yet been well-clarified. At present, pulmonary function tests are the only methods available for the evaluation of lung impairment due to these diseases, but their sensitivity and reliability are still limited. PURPOSE: The aim of this study was to correlate the quantitative score of cystic-aerial lesions obtained by a HRCT density mask (DM) software with pulmonary function data in DCLDs. METHODS: Spirometry, lung volumes, diffusion capacity, arterial blood gas (ABG) analysis, 6-min walking test (6-MWT), and HRCT with DM quantitative evaluation were performed in a cohort of 25 patients (lymphangioleiomyomatosis [LAM], 13 patients; Langerhans cells histiocytosis [LCH], 12 patients). Linear regression was used for the statistical analysis. The sum and mean of the air-trapping percentages at three different levels of DM study (ie, aortic arch, left lower lobe bronchus origin, and 2 cm from the diaphragmatic muscle), and various functional parameters and exercise performance values were matched for the analysis. RESULTS: An obstructive pattern was present in 13 patients (52%; LCH group, 8 patients; LAM group, 5 patients). A predominant restrictive pattern was detected only in three patients (12%; LCH group, two patients; LAM group, one patient). Nine patients (36%) walked 4 U). The results of DM quantitative study (sum and mean) significantly correlated with FVC (r = - 0.56; p < 0.001), FEV(1)/vital capacity (r = - 0.94; p < 0.002), midexpiratory phase of forced expiratory flow (r = - 0.84; p < 0.05), FEV(1) (r = - 0.82; p < 0.05), and diffusing capacity of the lung for carbon monoxide (r = - 0.82; p < 0.05), bronchial airway resistance (r = 0.79; p < 0.05), and distance walked on the 6-MWT (r = - 0.53; p < 0.05). No significant correlation was found with the results of ABG analysis. CONCLUSIONS: In DCLDs, HRCT scans with quantitative assessment performed by a DM software showed a very good correlation with functional parameters. Therefore, DM could be considered, in combination with a complete functional assessment, in the initial evaluation of patients affected by DCLDs. However, further studies are needed to assess its usefulness in the follow-up of these patient
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