5 Watt GaN HEMT Power Amplifier for LTE

This work presents the design and implementation of a stand-alone linear power amplifier at 2.4 GHz with high output power. A GaN HEMT transistor is selected for the design and implementation of the power amplifier. The device exhibits a gain of 11.7 dB and a drain efficiency of 39% for an output power of 36.7 dBm at 2.4 GHz for an input power of 25dBm. The carrier to intermodulation ratio is better than 25 dB for a two tone input signal of 25 dBm of total power and a spacing of 5 MHz. The fabricated device is also tested with LTE input signals of different bandwidths (5MHz to 20MHz)

Viral vector-mediated RNA interference in the retina

RNA interference (RNAi) is a highly conserved post-transcriptional gene silencing process triggered by double-stranded RNA (dsRNA) in eukaryotic cells. Elucidation of the RNAi regulatory pathway and its components has led to the identification of endogenous dsRNA molecules, termed microRNAs (miRNAs), which are transcribed as a single hairpin molecule prior to their maturation into a cytoplasmic dsRNA. The efficient gene silencing achieved by these short hairpin RNA (shRNA) molecules and the cumulative understanding of the RNAi pathway has prompted the development of hairpin expression vectors capable of mediating stable gene silencing in vitro and in vivo. The aim of this thesis is to evaluate the efficacy of viral vector-mediated RNAi in the retina using recombinant adeno-associated viruses (AAV) and lentiviruses that contain silencing hairpin cassettes to target four genes in murine photoreceptors and the retinal pigment epithelium (RPE). A detailed assessment of the utility and extend of RNAi in the retina using different viral vectors and hairpin designs is presented in this thesis. Lentiviral and AAV vectors were firstly used to silence GFP in vitro and in vivo as a proof of concept for vector mediated RNAi in the retina. Subsequently, we used lentivirally-mediated RNAi to study disease processes in the retina concentrating on tight junction (TJ) modulators ZO-1 and ZONAB and their role in RPE homeostasis, cell-cycle progression and epithelial-mesenchymal transition (EMT). Here we demonstrated how TJ misregulation can lead to RPE loss, proliferation or dedifferentiation; processes involved in pathological conditions such as atrophic age-related macular degeneration (AMD) and proliferative vitroretinopathy (PVR). Whilst lentivirally-mediated RNAi was used to elucidate aspects of retinal function and disease, AAV-mediated RNAi was used to probe the therapeutic potential of shRNAs by silencing Peripherin-2 (Prph2), the second most abundant retinal protein, using a miRNA-based hairpin. AAV2/8 particles were used to target endogenous Prph2 and evasion of silencing was demonstrated using an engineered Prph2 cDNA that could be used in a suppression and replacement approach for the treatment of dominant retinal disorders

Stakeholders\u27 satisfaction from a new Management Information System to confront the phenomenon of student absences

This paper proposes an Educational Management Information System (EMIS) that organizes all the administrative procedures with respect to monitoring school absences so that the related products have the same legal effect as the traditional procedures. The proposed EMIS covers the obligation of the Administration for complete, immediate and accurate information addressed to parents, reduces the operation cost of updating parents, removes workload from teachers, produces related documents with accuracy, provides the Administration with proper tools able to monitor student attendance and the tasks that the involved personnel has to accomplish. Based on the above-mentioned EMIS, we measure the satisfaction of all stakeholders, i.e., parents, teachers and executives using three types of questionnaires. Our results indicate that the proposed EMIS (a) satisfies the Administration\u27s obligation for keeping the parents informed with thorough, immediate and accurate information, (b) reduces the operational cost of parental updates, and (c) reduces the workload of teachers. Future work is also proposed. (DIPF/Orig.

Thermal bioclimate analysis for Europe and Italy

Thermal bioclimate indexes (as thermal comfort or heat stress indexes) are one of the main issues concerning tourism and health conditions especially for expected climate change. The Mediterranean area and countries such as Italy, Spain, France, Turkey and Greece, whose economies are markedly dependent on tourism, are vulnerable regions concerning climate change. In the present study thermal comfort and heat stress (here with the thermal index physiologically equivalent temperature—PET) are analysed in order to quantify the monthly conditions in this area. Additionally, based on climate change scenarios, the seasonal pattern of PET for the period 2070-2100 has been calculated. The results show that the expected conditions of thermal comfort especially for the Mediterranean and Italy will be higher, during summer, about two to three classes of thermal stress for the “business as usual” climate scenarios, and one class of thermal stress for winter. Adaptation and mitigation strategies are hence required for the protection of human health and tourism state and potentialities