382 research outputs found

    Impact of MgII interstellar medium absorption on near-ultraviolet exoplanet transit measurements

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    Ultraviolet (UV) transmission spectroscopy probes atmospheric escape, which has a significant impact on planetary atmospheric evolution. If unaccounted for, interstellar medium absorption (ISM) at the position of specific UV lines might bias transit depth measurements, and thus potentially affect the (non-)detection of features in transmission spectra. Ultimately, this is connected to the so called ``resolution-linked bias'' (RLB) effect. We present a parametric study quantifying the impact of unresolved or unconsidered ISM absorption in transit depth measurements at the position of the MgII h&k resonance lines (i.e. 2802.705 {\AA} and 2795.528 {\AA} respectively) in the near-ultraviolet spectral range. We consider main-sequence stars of different spectral types and vary the shape and amount of chromospheric emission, ISM absorption, and planetary absorption, as well as their relative velocities. We also evaluate the role played by integration bin and spectral resolution. We present an open-source tool enabling one to quantify the impact of unresolved or unconsidered MgII ISM absorption in transit depth measurements. We further apply this tool to a few already or soon to be observed systems. On average, we find that ignoring ISM absorption leads to biases in the MgII transit depth measurements comparable to the uncertainties obtained from the observations published to date. However, considering the bias induced by ISM absorption might become necessary when analysing observations obtained with the next generation space telescopes with UV coverage (e.g. LUVOIR, HABEX), which will provide transmission spectra with significantly smaller uncertainties compared to what obtained with current facilities (e.g. HST).Comment: Accepted for publication in MNRA

    Instrumentation, Field Network and Process Automation for the Cryogenic System of the LHC Test String

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    CERN is now setting up String 2, a full-size prototype of a regular cell of the LHC arc. It is composed of two quadrupole, six dipole magnets, and a separate cryogenic distribution line (QRL) for the supply and recovery of the cryogen. An electrical feed box (DFB), with up to 38 High Temperature Superconducting (HTS) leads, powers the magnets. About 700 sensors and actuators are distributed along four Profibus DP and two Profibus PA field buses. The process automation is handled by two controllers, running 126 Closed Control Loops (CCL). This paper describes the cryogenic control system, associated instrumentation, and their commissioning

    Perspectives on the implementation of screening and treatment for depression and alcohol Use disorder in primary care in Colombia

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    Q2Depression and alcohol use disorder (AUD) greatly contribute to the burden of disease worldwide, and have large impact on Colombia’s population. In this study, a qualitative analysis evaluates the implementation of a technology-supported model for screening, decision support, and digital therapy for depression and AUD in Colombian primary care clinics. Patient, provider, and administrator interviews were conducted, exploring attitudes towards depression and AUD, attitudes towards technology, and implementation successes and challenges. Researchers used qualitative methods to analyze interview themes. Despite stigma around depression and AUD, the model improved provider capacity to diagnose and manage patients, helped patients feel supported, and provided useful prevalence data for administrators. Challenges included limited provider time and questions about sustainability. The implementation facilitated the identifcation, diagnosis, and care of patients with depression and AUD. There is ongoing need to decrease stigma, create stronger networks of mental health professionals, and transition intervention ownership to the healthcare center.Revista Internacional - Indexad

    The Cryogenic System for the LHC Test String 2: Design, Commissioning and Operation

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    A 107-m long superconducting magnet string representing a full-cell of the LHC machine was designed for assembly and commissioning at CERN in order to validate the final design choices. This new facility, thereafter called Test String 2, and its cryogenic infrastructure cons ist of feed and return boxes coupled via transfer lines to a 6 kW @ 4.5 K refrigerator and to a low pressure pumping group, a separate cryogenic distribution line, an electrical feed box with HTS current leads, 2 quadrupole and 6 dipole prototype and pre-series superconducting magnets

    Patterns of Public Participation: Opportunity Structures and Mobilization from a Cross-National Perspective

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    PURPOSE: The paper summarizes data from twelve countries, chosen to exhibit wide variation, on the role and place of public participation in the setting of priorities. It seeks to exhibit cross-national patterns in respect of public participation, linking those differences to institutional features of the countries concerned. DESIGN/METHODOLOGY/APPROACH: The approach is an example of case-orientated qualitative assessment of participation practices. It derives its data from the presentation of country case studies by experts on each system. The country cases are located within the historical development of democracy in each country. FINDINGS: Patterns of participation are widely variable. Participation that is effective through routinized institutional processes appears to be inversely related to contestatory participation that uses political mobilization to challenge the legitimacy of the priority setting process. No system has resolved the conceptual ambiguities that are implicit in the idea of public participation. ORIGINALITY/VALUE: The paper draws on a unique collection of country case studies in participatory practice in prioritization, supplementing existing published sources. In showing that contestatory participation plays an important role in a sub-set of these countries it makes an important contribution to the field because it broadens the debate about public participation in priority setting beyond the use of minipublics and the observation of public representatives on decision-making bodies

    Why Wait Until Our Community Gets Cancer?: Exploring CRC Screening Barriers and Facilitators in the Spanish-Speaking Community in North Carolina

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    Colorectal cancer (CRC) is a leading cause of death among Hispanics in the United States. Despite the benefits of CRC screening, many Hispanics are not being screened. Using a combined methodology of focus groups and discrete choice experiment (DCE) surveys, the objectives for this research were as follows: (1) to improve understanding of preferences regarding potential CRC screening program characteristics, and (2) to improve understanding of the barriers and facilitators around CRC screening with the Hispanic, immigrant community in North Carolina. Four gender-stratified focus groups were conducted and DCE surveys were administered to 38 Spanish-speaking individuals across four counties in North Carolina. In-depth content analysis was used to examine the focus group data; descriptive analyses and mean attribute importance scores for cost of screening and follow-up care, travel time, and test options were calculated from DCE data. Data analyses showed that this population has a strong interest in CRC screening but experience barrier such as lack of access to resources, cost uncertainty, and stigma. Some of these barriers are unique to their cultural experiences in the United States, such as an expressed lack of tailored CRC information. Based on the DCE, cost variables were more important than testing options or travel time. This study suggests that Hispanics may have a general awareness of and interest in CRC screening, but multiple barriers prevent them from getting screened. Special attention should be given to designing culturally and linguistically appropriate programs to improve access to healthcare resources, insurance, and associated costs among Hispanics

    Validation and Performance of the LHC Cryogenic System through Commissioning of the First Sector

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    The cryogenic system [1] for the Large Hadron Collider accelerator is presently in its final phase of commissioning at nominal operating conditions. The refrigeration capacity for the LHC is produced using eight large cryogenic plants and eight 1.8 K refrigeration units installed on five cryogenic islands. Machine cryogenic equipment is installed in a 26.7-km circumference ring deep underground tunnel and are maintained at their nominal operating conditions via a distribution system consisting of transfer lines, cold interconnection boxes at each cryogenic island and a cryogenic distribution line. The functional analysis of the whole system during all operating conditions was established and validated during the first sector commissioning in order to maximize the system availability. Analysis, operating modes, main failure scenarios, results and performance of the cryogenic system are presented

    Suppressed Far-UV stellar activity and low planetary mass-loss in the WASP-18 system

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    WASP-18 hosts a massive, very close-in Jupiter-like planet. Despite its young age (Râ€ČHK activity parameter lies slightly below the basal level; there is no significant time-variability in the log Râ€ČHK value; there is no detection of the star in the X-rays. We present results of far-UV observations of WASP-18 obtained with COS on board of HST aimed at explaining this anomaly. From the star’s spectral energy distribution, we infer the extinction (E(B − V) ≈ 0.01mag) and then the ISM column density for a number of ions, concluding that ISM absorption is not the origin of the anomaly. We measure the flux of the four stellar emission features detected in the COS spectrum (C II, C III, C IV, Si IV). Comparing the C II/C IV flux ratio measured for WASP-18 with that derived from spectra of nearby stars with known age, we see that the far-UV spectrum of WASP-18 resembles that of old (>5Gyr), inactive stars, in stark contrast with its young age. We conclude that WASP-18 has an intrinsically low activity level, possibly caused by star-planet tidal interaction, as suggested by previous studies. Re-scaling the solar irradiance reference spectrum to match the flux of the Si IV line, yields an XUV integrated flux at the planet orbit of 10.2 erg s−1 cm−2. We employ the rescaled XUV solar fluxes to model of the planetary upper atmosphere, deriving an extremely low thermal mass-loss rate of 10−20MJ Gyr−1. For such high-mass planets, thermal escape is not energy limited, but driven by Jeans escape

    Baseline Configuration of the Cryogenic System for the International Linear Collider

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    The paper discusses the main constraints and boundary conditions and describes the baseline configuration of the International Linear Collider (ILC) cryogenic system. The cryogenic layout, architecture and the cooling principle are presented. The paper addresses a plan for study and development required to demonstrate and improve the performance, to reduce cost and to attain the desired reliability
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