Teaching Experiences with E-Learning Network Infrastructures

Abstract. Computer-based learning environments provide the opportunity to promote students interactivity and meet their individual needs. Because of the advantages of such approach, the computer-based teaching is becoming very popular in universities and in other educational institutes. However, very often the solutions proposed to support the educational activities are not inter-operable and lack of a suitable network infrastructure. In this paper, we report the results of several teaching experiences gathered from more than one year of activities in various research projects. Our first step has been the development of a platform able to fully integrate the new powerful teaching tools, such as the virtual blackboard, and network transport services. From these experiences, we realized that the learning quality would be improved if students interactively participate to the learning process. Then, in a later experimentation, we proposed and validated a model of e-classroom, which would guarantee the mobility to students and preserve their identity. We show that this kind of mobile-learning is only possible whereas an advanced networking technology, such as Mobile IPv6, is enabled

Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes

Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR < 60 mL/min/1.73 m2) or eGFR reduction > 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR < 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR > 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening

Intra-arterial urokinase infusion in diabetic patients with rapidly progressive ischemic foot lesions.

OBJECTIVE: The effectiveness of local intra-arterial thrombolysis by urokinase was evaluated in eight non-insulin-dependent diabetic patients with angiographic evidence of infrapopliteal occlusive disease and rapidly progressive foot lesions. RESEARCH DESIGN AND METHODS: With an electric peristaltic pump, urokinase was infused for 96 h by a 5-6 F catheter introduced into the femoral artery and placed immediately above the occluded infrapopliteal arteries. After baseline, angiography was repeated at 24- to 48-h intervals and at conclusion of the treatment. RESULTS: Six patients showed immediate improvement ofclinical symptoms. Angiography revealed the reestablishment of blood flow in collateral vessels of the leg and foot in the dorsal pedal artery in three patients and in the plantar arch in two. Recanalization of the major arteries of the trifurcation was not achieved. After 12 mo of follow-up, all limbs were salvaged, although four patients required vascular reconstruction to further improve foot perfusion and complete healing. CONCLUSIONS: Intra-arterial urokinase, which opens collateral and smaller vessels of the leg and foot in patients with diabetes, may be effective in improving blood flow in lower extremities and in making the patient a better candidate for vascular surgery

Characterization-oriented design of E-band Variable-Gain Amplifiers in BiCMOS technology

Design and characterization of both a single-stage and a 2-stage Variable Gain Amplifier operating at E-Band is presented. Characterization issues of differential RF amplifiers are discussed, and integrated input and output baluns seem to be an easy solution for on-chip or on-board preliminary characterization by standard 2-port Network Analyzer. Amplifiers have been prototyped in a SiGe BiCMOS commercial technology, and exhibit about 22 dB of gain control range. After balun de-embedding, more than 10 dB of maximum gain has been also demonstrated for both amplifiers

Compact E-band I/Q receiver in SiGe BiCMOS for 5G backhauling applications

The implementation of backhauling links poses several challenges to the designers which are requested to limit the hardware costs in the framework of complex millimeter wave radio systems. This work presents a monolithically integrated E-band I/Q receiver covering the whole bandwidth from 71 to 86 GHz. The chip was implemented in a 55 nm SiGe BiCMOS technology which allows reaching a high level of integration. The receiver is based on a Low Noise Amplifier (LNA) stage and a Variable-Gain Amplifier (VGA) which provide a -11 dBm IP1dB. A double balanced mixer provides I/Q baseband outputs through a reduced-size differential phase shifter which allows to contain the chip size to 1.8 mm