330 research outputs found

    Beam Dynamics Studies for the CLIC Main Linac

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    The implications of long-range wakefields on the beam quality are investigated through a detailed beam dynamics study. Injection offsets are considered and the resulting emittance dilution recorded, including systematic sources of error. These simulations have been conducted for damped and detuned structures (DDS) and for waveguide damped structures-both for the CLIC collider.Comment: 3 pages, 6 figures, IPAC1

    The synthesis of optimal controls for linear problems with retarded controls

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    Synthesis of optimal controls for linear systems with retarded control

    EUPRAXIA@SPARC_LAB: Beam Dynamics studies for the X-band Linac

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    In the framework of the Eupraxia Design Study an advanced accelerator facility EUPRAXIA@SPARC_LAB has been proposed to be realized at Frascati (Italy) Laboratories of INFN. Two advanced acceleration schemes will be applied, namely an ultimate high gradient 1 GeV X-band linac together with a plasma acceleration stage to provide accelerating gradients of the GeV/m order. A FEL scheme is foreseen to produce X-ray beams within 3-10 nm range. A 500-TW Laser system is also foreseen for electron and ion production experiments and a Compton backscattering Interaction is planned together with extraction beamlines at intermediate electron beam energy for neutron beams and THz radiation production. The electron beam dynamics studies in the linac are here presented together with the preliminary machine layout.Comment: 5 pages, 3 figures, NIM-A proceedings of EAAC201

    Transitions between care settings after enrolment in a palliative care service in Italy: a retrospective analysis

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    This study was a retrospective analysis of prospectively collected data that aimed to map patients' care transitions following admission to a specialist palliative care service in Italy called Antea Centre. Patients' data was extracted from the Antea local database from 2007 to 2011. External transitions were defined as a change in the setting of care, with the patient no longer being cared for by Antea staff. Internal transitions were defined as a change in the setting of care, with the care still being provided by Antea staff. A total of 1123 patients out of 5313 admitted to the palliative service (21%) experienced transitions. Patients who experienced no transitions after their admission to the palliative care service were more likely to have a Karnofsky Performance Scale Index <30, to have been referred by a hospital physician, to have a shorter survival time, and to have home as their place of death (P<0.001). Although the patients with no transitions had worse clinical conditions, organisations should pay attention to reducing the possible negative effects of transitions, such as discontinuity of care and poor coordination

    Crab cavities for linear colliders

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    Crab cavities have been proposed for a wide number of accelerators and interest in crab cavities has recently increased after the successful operation of a pair of crab cavities in KEK-B. In particular crab cavities are required for both the ILC and CLIC linear colliders for bunch alignment. Consideration of bunch structure and size constraints favour a 3.9 GHz superconducting, multi-cell cavity as the solution for ILC, whilst bunch structure and beam-loading considerations suggest an X-band copper travelling wave structure for CLIC. These two cavity solutions are very different in design but share complex design issues. Phase stabilisation, beam loading, wakefields and mode damping are fundamental issues for these crab cavities. Requirements and potential design solutions will be discussed for both colliders.Comment: 3 pages. To be published in proceedings of LINAC 2008, Victoria, Canad

    Workload, Job Satisfaction and Quality of Nursing Care in Italy: A Systematic Review of Native Language Articles

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    Nursing research is rapidly increasing, yet contributions from numerous countries that may interest the international nursing community are impeded because many research articles are published in authors’ native language and not in English. The objectives of this work were to systematically review papers published in Italian related to job satisfaction and the quality of nursing care, and to discuss their findings in light of the international literature. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method was used. The Directory of Open Access Journals (DOAJ) and Indice della Letteretura Italiana di Scienze Infermieristiche (ILISI) databases were consulted for eligible studies published from January 2015 to November 2022. Two hundred sixteen papers were identified, 11 of which were selected for review: 8 on job satisfaction, two on workload issues, and 1 on quality of nursing care. The quality of included studies was assessed through the Effective Public Health Practice Project quality assessment tool (EPHPP). The results of our review were in line with those of international literature, and they can help to fill the knowledge gap on the quality of nursing performance in Italian care settings. In addition, the proposed method can provide further elements of discussion among literature providers and reviewers

    Psychometric Properties of the Italian Version of the Leader Member Exchange Scale (LMX-7): A Validation Study

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    For decades, scholars have studied leader–member exchange (LMX) relationships to understand and explain the effects of leadership on follower attitudes and performance outcomes within work settings. One available instrument to measure these aspects is the LMX-7 scale. This measurement has been widely used in empirical studies, but its psychometric properties have been poorly explored. The aim of this study was to test the psychometric characteristics (content, structural and construct validity, and reliability) of the Italian version of the LMX-7 scale and to support its cultural adaptation. We used a cross-sectional multi-center design. The forward–backward translation process was used to develop the Italian version of the scale. The scale was administered through an online survey to 837 nurses and nurse managers working in different settings. The factorial structure was tested using both exploratory and confirmatory factor analyses (EFA and CFA), and reliability was evaluated using Cronbach’s alpha. For the construct validity, we used hypothesis testing and differentiation by known groups. The Italian version of the LMX-7 scale presented one dimension. All the psychometric tests performed confirmed its validity and suggested its usefulness for future research

    Proposal for Single-Bunch Collimator Wakefield Measurements at SLAC ESTB

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    Collimator wakefields in the Beam Delivery System (BDS) of future linear colliders, such as the International Linear Collider (ILC) and the Compact Linear Collider (CLIC), can be an important source of emittance growth and beam jitter amplification, consequently degrading the luminosity. Therefore, a better understanding of collimator wakefield effects is essential to optimise the collimation systems of future linear colliders in order to minimise wakefield effects. In the past, measurements of single-bunch collimator wakefields have been carried out at SLAC with the aim of benchmarking theory, numerical calculations and experiments. Those studies revealed some discrepancies between the measurements and the theoretical models. New experimental tests using available beam test facilities, such as the End Station A Test Beam (ESTB) at SLAC, would help to improve our understanding on collimator wakefields. ESTB will provide the perfect test bed to investigate collimator wakefields for different bunch length conditions, relevant for both ILC (300 micrometers nominal bunch length) and CLIC (44 micrometers nominal bunch length) studies. Here we propose to perform new experimental tests of collimator wakefield effects on electron/positron beams at SLAC ESTB.Comment: 22 pages, 19 figure

    Assessment of the Psychometric Characteristics of the Italian Version of the Nurse Manager Actions Scale

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    Nurse managers play a vital role in healthcare organizations, wielding the ability to substantially enhance work environments, foster nurses’ autonomy, and bolster retention within workplaces. In this context, this study focuses on the Nurse Manager Actions scale, aiming to evaluate its items’ scalability as well as the scale’s validity and reliability among nurses and nurse managers operating within the Italian healthcare context. The study protocol was not registered. To ensure linguistic and cultural alignment, an iterative and collaborative translation process was undertaken. Subsequently, a multi-center cross-sectional design was adopted. Using a web-survey approach, data were collected among 683 nurses and 188 nurse managers between August 2022 and January 2023. The Nurse Manager Actions scale was found to be a valid and reliable instrument in Italian after a Mokken Scale Analysis. For nurses (HT = 0.630, Molenaar–Sijtsma rho = 0.890), the scale included 6 items, while 11 items were confirmed for nurse managers (HT = 0.620, Molenaar–Sijtsma rho = 0.830). Nurse Manager Actions scale scores were correlated with increased satisfaction and decreased intention to leave for both nurses and nurse managers. The employed validation process enhanced the scale validity for use in Italy and provided a model for other researchers to follow when assessing similar measures in different populations. Measuring and empowering nurse manager actions in work contexts is essential to improve the general well-being and retention of nurses, especially in the current nursing shortage

    Appraisal and Evaluation of the Learning Environment Instruments of the Student Nurse: A Systematic Review Using COSMIN Methodology

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    Background: Nursing education consists of theory and practice, and student nurses’ perception of the learning environment, both educational and clinical, is one of the elements that determines the success or failure of their university study path. This study aimed to identify the currently available tools for measuring the clinical and educational learning environments of student nurses and to evaluate their measurement properties in order to provide solid evidence for researchers, educators, and clinical tutors to use in the selection of tools. Methods: We conducted a systematic review to evaluate the psychometric properties of self-reported learning environment tools in accordance with the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) Guidelines of 2018. The research was conducted on the following databases: PubMed, CINAHL, APA PsycInfo, and ERIC. Results: In the literature, 14 instruments were found that evaluate both the traditional and simulated clinical learning environments and the educational learning environments of student nurses. These tools can be ideally divided into first-generation tools developed from different learning theories and second-generation tools developed by mixing, reviewing, and integrating different already-validated tools. Conclusion: Not all the relevant psychometric properties of the instruments were evaluated, and the methodological approaches used were often doubtful or inadequate, thus threatening the instruments’ external validity. Further research is needed to complete the validation processes undertaken for both new and already developed instruments, using higher-quality methods and evaluating all psychometric propertie
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