Effects of surface forcing on the seasonal cycle of the eastern equatorial Pacific

The roles of zonal and meridional wind stress and of surface heat flux in the seasonal cycle of sea surface temperature (SST) are examined with a primitive equation (PE) model of the tropical Pacific Ocean. While a variety of previous numerical and observational studies have examined the seasonal cycle of SST in the eastern tropical Pacific, it is noteworthy that different mechanisms have been invoked as primary in each case and different conclusions have been reached regarding the relative importance of the various components of surface forcing. Here, we perform a series of numerical experiments in which different components of the surface forcing are eliminated and the resulting upper ocean variability is compared with that of the climatological experiment. The model used for these experiments reproduces a realistic climatological seasonal cycle, in which SST emerges as an independent quantity. We find that the different cases all produce qualitatively reasonable seasonal cycles of SST, though only the most complete model is also able to reproduce the seasonal cycle of near surface currents, tropical instability waves (TIWs), and net surface heat fluxes consistent with historical observations. These results indicate that simply reproducing a qualitatively accurate seasonal cycle of SST does not necessarily allow meaningful conclusions to be made about the relative importance of the different components of surface forcing. The results described here also suggest that a model simulation must at least reproduce all the documented near surface kinematic features of the equatorial Pacific cold tongue region reasonably well, before accurate inferences can be made from model experiments. This provides useful guidelines to current efforts to develop and evaluate more complex fully coupled air-sea models and shows that results for simple or intermediate ocean models that do not have this level of fidelity to the observations will be difficult to interpret

The ATLAS barrel level-1 Muon Trigger Sector-Logic/RX off-detector trigger and acquisition board

The ATLAS experiment uses a system of three concentric layers of Resistive Plate Chambers (RPC) detector for the Level-1 Muon Trigger in the air-core barrel toroid region. The trigger algorithm looks for hit coincidences within different detector layers inside the programmable geometrical road which defines the transverse momentum cut. The on-detector electronics that provides the trigger and detector readout functionalities collects input signals coming from the RPC front-end. Trigger and readout data are then sent via optical fibres to the off-detector electronics. Six or seven optical fibres from one of the 64 trigger sectors go to one Sector-Logic/RX module, that later elaborates the collected trigger and readout data, and sends data respectively to the Read-Out Driver modules and to the Central Level-1 Trigger. We present the functionality and the implementation of the VME Sector-Logic/RX module, and the configuration of the system for the first cosmic ray data collected using this module

Silicon Superconducting Quantum Interference Device

We have studied a Superconducting Quantum Interference SQUID device made from a single layer thin film of superconducting silicon. The superconducting layer is obtained by heavily doping a silicon wafer with boron atoms using the Gas Immersion Laser Doping (GILD) technique. The SQUID device is composed of two nano-bridges (Dayem bridges) in a loop and shows magnetic flux modulation at low temperature and low magnetic field. The overall behavior shows very good agreement with numerical simulations based on the Ginzburg-Landau equations.Comment: Published in Applied Physics Letters (August 2015

Radiation test and application of FPGAs in the ATLAS Level 1 Trigger

The front-end system of the Silicon Drift Detectors (SDDs) of the ALICE experiment is made of two ASICs. The first chip performs the preamplification, temporary analogue storage and analogue-to-digital conversion of the detector signals. The second chip is a digital buffer that allows for a significant reduction of the connection from the front-end module to the outside world. In this paper, the results achieved on the first complete prototype of the front-end system for the SDDs of ALICE are presented

Contactless photoconductivity measurements on (Si) nanowires

Conducting nanowires possess remarkable physical properties unattainable in bulk materials. However our understanding of their transport properties is limited by the difficulty of connecting them electrically. In this Letter we investigate phototransport in both bulk silicon and silicon nanowires using a superconducting multimode resonator operating at frequencies between 0.3 and 3 GHz. We find that whereas the bulk Si response is mainly dissipative, the nanowires exhibit a large dielectric polarizability. This technique is contactless and can be applied to many other semiconducting nanowires and molecules. Our approach also allows to investigate the coupling of electron transport to surface acoustic waves in bulk Si and to electro-mechanical resonances in the nanowires

First Ex-Vivo Validation of a Radioguided Surgery Technique with beta- Radiation

Purpose: A radio-guided surgery technique with beta- -emitting radio-tracers was suggested to overcome the effect of the large penetration of gamma radiation. The feasibility studies in the case of brain tumors and abdominal neuro-endocrine tumors were based on simulations starting from PET images with several underlying assumptions. This paper reports, as proof-of-principle of this technique, an ex-vivo test on a meningioma patient. This test allowed to validate the whole chain, from the evaluation of the SUV of the tumor, to the assumptions on the bio-distribution and the signal detection. Methods: A patient affected by meningioma was administered 300 MBq of 90Y-DOTATOC. Several samples extracted from the meningioma and the nearby Dura Mater were analyzed with a beta- probe designed specifically for this radio-guided surgery technique. The observed signals were compared both with the evaluation from the histology and with the Monte Carlo simulation. Results: we obtained a large signal on the bulk tumor (105 cps) and a significant signal on residuals of $\sim$0.2 ml (28 cps). We also show that simulations predict correctly the observed yields and this allows us to estimate that the healthy tissues would return negligible signals (~1 cps). This test also demonstrated that the exposure of the medical staff is negligible and that among the biological wastes only urine has a significant activity. Conclusions: This proof-of-principle test on a patient assessed that the technique is feasible with negligible background to medical personnel and confirmed that the expectations obtained with Monte Carlo simulations starting from diagnostic PET images are correct.Comment: 17 pages, 4 Figs, Accepted by Physica Medic

Private costs on water conservation: study case at Cantareira Mantiqueira Corridor Region.

This study aims to evaluate the private opportunity cost for an extensive forest recover program in the Cantareira-Mantiqueira Corridor Region and discuss its results focusing on three central questions: i. what is the private opportunity cost of forest restoration for the main land use activities in the Cantareira-Mantiqueira Corridor Region? ii. how the private opportunity costs varies throughout the region? iii. What are the most cost-effectiveness PES strategies available for the Cantareira- Mantiqueira Corridor Region

Towards a Radio-guided Surgery with β−\beta^{-} Decays: Uptake of a somatostatin analogue (DOTATOC) in Meningioma and High Grade Glioma

A novel radio guided surgery (RGS) technique for cerebral tumors using $\beta^{-}$ radiation is being developed. Checking the availability of a radio-tracer that can deliver a $\beta^{-}$ emitter to the tumor is a fundamental step in the deployment of such technique. This paper reports a study of the uptake of 90Y labeled (DOTATOC) in the meningioma and the high grade glioma (HGG) and a feasibility study of the RGS technique in these cases.Comment: 21 pages, 5 figure