A Dual-Band MMIC Low frequency 180 ° Hybrid

In this paper design formulas,for the development of an unusual 180 ° hybrid working in two distinct frequency bands,are provided.In particular the design formulas of a lumped-element rat race,starting from a conventional transmission-line rat-race,are found out.In order to generalize the matching problem the input and output port impedances are considered to be different

RF Energy Harvesting for LTE Systems

This work is aimed to acquire knowledge on RF-DC conversion systems working on Long Term Evolution (LTE) bands around 806 MHz. The study is carried out, firstly designing and realizing an RF-DC conversion circuit and then measuring the voltage levels obtained from the implemented circuit, at the selected frequency. Ambient radio frequency sources are considered, thus low power levels around -20dBm have been assumed for the circuit design

An Active Non-Reciprocal Phase Shifter Topology

A novel hybrid active nonreciprocal phase shifter (NRPS) topology is proposed in this contribution. A test vehicle of the topology, realized in hybrid form to operate in L-band with a 90°differential phase shift has been realized and tested. The resulting system exhibits a 28% bandwidth centered at 1.4 GHz. © 2012 Wiley Periodicals, Inc

Genetic and physiological traits conferring tolerance to ocean acidification in mesophotic corals

The integrity of coral reefs worldwide is jeopardized by ocean acidification (OA). Most studies conducted so far have focused on the vulnerability to OA of corals inhabiting shallow reefs while nothing is currently known about the response of mesophotic scleractinian corals. In this study, we assessed the susceptibility to OA of corals, together with their algal partners, inhabiting a wide depth range. We exposed fragments of the depth generalist coral Stylophora pistillata collected from either 5 or 45 m to simulated future OA conditions, and assessed key molecular, physiological and photosynthetic processes influenced by the lowered pH. Our comparative analysis reveals that mesophotic and shallow S. pistillata corals are genetically distinct and possess different symbiont types. Under the exposure to acidification conditions, we observed a 50% drop of metabolic rate in shallow corals, whereas mesophotic corals were able to maintain unaltered metabolic rates. Overall, our gene expression and physiological analyses show that mesophotic corals possess a greater capacity to cope with the effects of OA compared to their shallow counterparts. Such capability stems from physiological characteristics (i.e., biomass and lipids energetics), a greater capacity to regulate cellular acid–base parameters, and a higher baseline expression of cell adhesion and extracellular matrix genes. Moreover, our gene expression analysis suggests that the enhanced symbiont photochemical efficiency under high pCO2 levels could prevent acidosis of the host cells and it could support a greater translocation of photosynthates, increasing the energy pool available to the host. With this work, we provide new insights on the response to OA of corals living at mesophotic depths. Our investigation discloses key genetic and physiological traits underlying the potential for corals to cope with future OA conditions

RF Energy Harvesting for DVB-T Signals

This paper presents design, realization and measurements of an energy harvesting circuit, working on different UHF TV channels, from 470 MHz to 550 MHz. Ambient radio frequency sources are considered, thus low power levels have been assumed for the circuit design. The circuit was implemented and several measurements were carried out for different frequencies, loads and input power level

Realization and measurement of an RF energy harvesting circuit working on LTE frequency bands

This paper presents design measurements of an energy harvesting circuit LTE frequency bands. Ambient radio freque considered, thus low power levels have been circuit design. The circuit was implement measurements were carried out for different f and input power levels

Design and implementation of ambient RF energy harvesting circuits

This paper presents design strategies and measurements of two RF energy harvesting circuits working at UHF frequencies (around 480 MHz). Ambient RF sources are considered so for the circuit designs low power levels have been assumed. The circuits were implemented and the RF/DC conversion efficiency was measured

Seawater carbonate chemistry and proportion of transcriptome changing, coral protein concentration, respiration rates, algal photosynthetic parameters

The integrity of coral reefs worldwide is jeopardized by ocean acidification (OA). Most studies conducted so far have focused on the vulnerability to OA of corals inhabiting shallow reefs, while nothing is currently known about the response of mesophotic scleractinian corals. In this study we assessed the susceptibility to OA of corals, together with their algal partners, inhabiting a wide depth range. We exposed fragments of the depth generalist coral Stylophora pistillata collected from either 5 or 45 meters to simulated future OA conditions, and assessed key molecular, physiological and photosynthetic processes influenced by the lowered pH. Our comparative analysis reveals that mesophotic and shallow S. pistillata corals are genetically distinct and possess different symbiont types. Under the exposure to acidification conditions, we observed a 50% drop of metabolic rate in shallow corals, whereas mesophotic corals were able to maintain unaltered metabolic rates. Overall, our gene expression and physiological analyses show that mesophotic corals possess a greater capacity to cope with the effects of OA compared to their shallow counterparts. Such capability stems from physiological characteristics (i.e. biomass and lipids energetics), a greater capacity to regulate cellular acid-base parameters, and a higher baseline expression of cell-adhesion and extracellular matrix genes. Moreover, our gene expression analysis suggests that the enhanced symbiont photochemical efficiency under high pCO₂ levels could prevent acidosis of the host cells and it could support a greater translocation of photosynthates, increasing the energy pool available to the host. With this work, we provide new insights on the response to OA of corals living at mesophotic depths. Our investigation discloses key genetic and physiological traits underlying the potential for corals to cope with future OA conditions

Reconfigurable Matching Network for RF Energy Harvesting Circuits

This work is aimed to acquire knowledge on the RF/DC conversion process, based on hybrid technology and using a reconfigurable matching network. For this purpose, a test circuit operating at UHF TV broadcasting frequencies is designed, realized and measured for different frequencies, input power levels and load values. © 2014 IEEE