Design and Field Measurements of a Linear Accelerator Endowed with Single Feed with Movable Short Coupler

Field asymmetries in the rf coupler of accelerating structures degrade the projected beam transverse emittance, especially at low energy. This paper presents an alternative single feed coupler design that reduces the dipolar and the quadrupolar field components by exploiting a movable short circuit placed on the opposite waveguide. The structure has been simulated and optimized with the Ansys HFSS simulation code. RF measurements on an aluminum prototype machined in the "Elettra - Sincrotrone Trieste S.C.p.A.", are here presented. Such results are in good agreement with the simulations

Spatial interactions in agent-based modeling

Agent Based Modeling (ABM) has become a widespread approach to model complex interactions. In this chapter after briefly summarizing some features of ABM the different approaches in modeling spatial interactions are discussed. It is stressed that agents can interact either indirectly through a shared environment and/or directly with each other. In such an approach, higher-order variables such as commodity prices, population dynamics or even institutions, are not exogenously specified but instead are seen as the results of interactions. It is highlighted in the chapter that the understanding of patterns emerging from such spatial interaction between agents is a key problem as much as their description through analytical or simulation means. The chapter reviews different approaches for modeling agents' behavior, taking into account either explicit spatial (lattice based) structures or networks. Some emphasis is placed on recent ABM as applied to the description of the dynamics of the geographical distribution of economic activities, - out of equilibrium. The Eurace@Unibi Model, an agent-based macroeconomic model with spatial structure, is used to illustrate the potential of such an approach for spatial policy analysis.Comment: 26 pages, 5 figures, 105 references; a chapter prepared for the book "Complexity and Geographical Economics - Topics and Tools", P. Commendatore, S.S. Kayam and I. Kubin, Eds. (Springer, in press, 2014

Adherence to recommendations for cervical and breast cancer screening in systemic sclerosis.

The aim of the study was to evaluate the adherence of systemic sclerosis (SSc) female patients to cervix and breast cancer screening procedures, as suggested by local guidelines. A cohort of 84 SSc women was asked if they had undergone mammography and Pap test during the previous 2- and 3-year intervals, as indicated according to the Italian recommendations. The results were compared with those collected in patients affected by other chronic rheumatic disorders and in the general population. More than 85% of SSc women declared to comply with an age-related cervix and breast cancer screening schedule. The data were similar to those collected in patients affected by other chronic rheumatic disorders, whereas the subjects belonging to the general population reported to undergo breast cancer screening more frequently. Among SSc women, neither the educational level, nor the lung and skin involvement influenced their cancer screening program compliance. Only a positive history of ischemic digital ulcers seemed to interfere with mammography. Our study reported a very high percentage of SSc female patients who adhered to programs for the early detection of cervical and breast cancer. The significant adherence to guidelines may be due to the schedule adopted by the local health public service, which regularly invites eligible subjects by mail to undergo cancer screening at no charge

Optimizing hot electron harvesting at planar metal–semiconductor interfaces with titanium oxynitride thin films

Understanding metal-semiconductor interfaces is critical to the advancement of photocatalysis and sub-bandgap solar energy harvesting where electrons in the metal can be excited by sub-bandgap photons and extracted into the semiconductor. In this work, we compare the electron extraction efficiency across Au/TiO2 and titanium oxynitride (TiON)/TiO2-x interfaces, where in the latter case the spontaneously forming oxide layer (TiO2-x) creates a metal-semiconductor contact. Time-resolved pump-probe spectroscopy is used to study the electron recombination rates in both cases. Unlike the nanosecond recombination lifetimes in Au/TiO2, we find a bottleneck in the electron relaxation in the TiON system, which we explain using a trap-mediated recombination model. Using this model, we investigate the tunability of the relaxation dynamics with oxygen content in the parent film. The optimized film (TiO0.5N0.5) exhibits the highest carrier extraction efficiency (NFC ≈ 2.8 × 1019 m-3), slowest trapping, and an appreciable hot electron population reaching the surface oxide (NHE ≈ 1.6 × 1018 m-3). Our results demonstrate the productive role oxygen can play in enhancing electron harvesting and prolonging electron lifetimes, providing an optimized metal-semiconductor interface using only the native oxide of titanium oxynitride

Implementation of Radio-Frequency Deflecting Devices for Comprehensive High-Energy Electron Beam Diagnosis

In next-generation light sources, high-brightness electron beams are used in a free-electron laser configuration to produce light for use by scientists and engineers in numerous fields of research. High-brightness beams are described for such light sources as having low transverse and longitudinal emittances, high peak currents, and low slice emittance and energy spread. The optimal generation and preservation of such high-brightness electron beams during the acceleration process and propagation to and through the photon-producing element is imperative to the quality and performance of the light source. To understand the electron beam's phase space in the accelerating section of a next-generation light source machine, we employed radio-frequency cavities operating in a deflecting mode in conjunction with a magnetic spectrometer and imaging system for both low (250 MeV) and high (1.2 GeV) electron energies. This high-resolution, high-energy system is an essential diagnostic for the optimization and control of the electron beam in the FERMI light source generating fully transversely and longitudinally coherent light in the VUV to soft x-ray wavelength regimes. This device is located at the end of the linear accelerator in order to provide the longitudinal phase space nearest to the entrance of the photon-producing beam-lines. Here, we describe the design, fabrication, characterization, commissioning, and operational implementation of this transverse deflecting cavity structure diagnostic system for the high-energy (1.2 GeV) regime

Efficacy and safety of rituximab with and without methotrexate in the treatment of rheumatoid arthritis patients: Results from the GISEA register.

Rituximab (RTX) is a monoclonal anti-CD20 antibody approved for the treatment of rheumatoid arthritis (RA) in association with methotrexate (MTX)

Assessing the presence of shared genetic architecture between Alzheimer's disease and major depressive disorder using genome-wide association data

We are grateful to the families and individuals who took part in the GS:SFHS and UKB studies, and to all those involved in participant recruitment, data collection, sample processing and QC, including academic researchers, clinical staff, laboratory technicians, clerical workers, IT staff, statisticians and research managers. This work is supported by the Wellcome Trust through a Strategic Award, reference 104036/Z/ 14/Z. We acknowledge with gratitude the financial support received from the Dr Mortimer and Theresa Sackler Foundation. This research has been conducted using the GS:SFHS and UK Biobank (project #4844) resources. GS:SFHS received core funding from the Chief Scientist Office of the Scottish Government Health Directorates [CZD/16/6] and the Scottish Funding Council [HR03006]. UKB was established using funding from the Wellcome Trust, Medical Research Council, the Scottish Government Department of Health, and the Northwest Regional Development Agency. DJP, IJD, TCR and AMM are members of the University of Edinburgh Centre for Cognitive Ageing and Cognitive Epidemiology, part of the cross council Lifelong Health and Wellbeing Initiative (MR/K026992/1). TCR is supported by Alzheimer's Scotland, through the Marjorie MacBeath bequest. Funding from the Biotechnology and Biological Sciences Research Council and Medical Research Council is gratefully acknowledged. We are grateful for the use of summary data from the International Genomics of Alzheimer's Project and the Major Depressive Disorder working group of the Psychiatric Genomics Consortium.Peer reviewedPublisher PD