130 research outputs found

    Monitoreo del estado de iones atrapados en una cavidad óptica

    Get PDF
    Tesis (Lic. en Física)--Universidad Nacional de Córdoba, Facultad de Matemática, Astronomía, Física y Computación, 2018.El objeto de estudio considerado en este trabajo es un ion en el interior de una cavidad óptica bombeada por un láser, en el régimen de acoplamiento dispersivo y en aproximación armónica. Este trabajo se propone complementar y continuar el estudio del espectro de emisión de la cavidad reportado en [1] C. Cormick and G. Morigi, “Ion chains in high-finesse cavities,” Phys. Rev. A, vol. 87, p. 013829, Jan 2013 y en [2] T. Fogarty, C. Cormick, H. Landa, V. M. Stojanović, E. Demler, and G. Morigi, “Nanofriction in cavity quantum electrodynamics,” Phys. Rev. Lett., vol. 115, p. 233602, Dec 2015. En particular, se analiza la conexión entre distintos rasgos espectrales y las características de la dinámica del sistema compuesto por los iones acoplados con la cavidad (por ejemplo, las frecuencias de los modos normales, su nivel de ocupación, o su grado de acoplamiento con el entorno). Se identifican métodos para medir propiedades del sistema en forma no invasiva, por medio de los fotones que escapan a través de los espejos

    Computer analysis, learning and creation of physical arrangements of information

    Get PDF
    Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.Includes bibliographical references (leaves 75-76).Humans' ability to arrange the individual pieces of a set of information is paramount to their understanding of the set as a whole. The physical arrangement of pieces of information yields important clues as to how those pieces are related. This thesis focuses on computer analysis of physical arrangements and use of perceived physical relations, such as horizontal and vertical alignment, in determining which pieces of information are most likely related. The computer program described in this thesis demonstrates that once a computer can deduce physical relations between pieces of information, it can learn to order the information as a human would with great accuracy. The information analysis methods presented in this thesis are of benefit to projects that deal with user collaboration and the sorting of data based on relative importance, such as the Electronic Card Wall (EWall) project.by Michael Alan Kahan.M.Eng

    Driving Interactions Efficiently in a Composite Few-Body System

    Get PDF
    We study how to efficiently control an interacting few-body system consisting of three harmonically trapped bosons. Specifically, we investigate the process of modulating the inter-particle interactions to drive an initially non-interacting state to a strongly interacting one, which is an eigenstate of a chosen Hamiltonian. We also show that for unbalanced subsystems, where one can individually control the different inter- and intra-species interactions, complex dynamics originate when the symmetry of the ground state is broken by phase separation. However, as driving the dynamics too quickly can result in unwanted excitations of the final state, we optimize the driven processes using shortcuts to adiabaticity, which are designed to reduce these excitations at the end of the interaction ramp, ensuring that the target eigenstate is reached

    Estimands: bringing clarity and focus to research questions in clinical trials

    Get PDF
    Precise specification of the research question and associated treatment effect of interest is essential in clinical research, yet recent work shows that they are often incompletely specified. The ICH E9 (R1) Addendum on Estimands and Sensitivity Analysis in Clinical Trials introduces a framework that supports researchers in precisely and transparently specifying the treatment effect they aim to estimate in their clinical trial. In this paper, we present practical examples to demonstrate to all researchers involved in clinical trials how estimands can help them to specify the research question, lead to a better understanding of the treatment effect to be estimated and hence increase the probability of success of the trial

    Variation in population levels of physical activity in European adults according to cross-European studies: a systematic literature review within DEDIPAC

    Get PDF
    peer-reviewedBackground: Physical inactivity is a well-known public health risk that should be monitored at the population level. Physical activity levels are often surveyed across Europe. This systematic literature review aims to provide an overview of all existing cross-European studies that assess physical activity in European adults, describe the variation in population levels according to these studies, and discuss the impact of the assessment methods. Methods: Six literature databases (PubMed, EMBASE, CINAHL, PsycINFO, SportDiscus and OpenGrey) were searched, supplemented with backward- and forward tracking and searching authors’ and experts’ literature databases. Articles were included if they reported on observational studies measuring total physical activity and/or physical activity in leisure time in the general population in two or more European countries. Each record was reviewed, extracted and assessed by two independent researchers and disagreements were resolved by a third researcher. The review protocol of this review is registered in the PROSPERO database under registration number CRD42014010334. Results: Of the 9,756 unique identified articles, twenty-five were included in this review, reporting on sixteen different studies, including 2 to 35 countries and 321 to 274,740 participants. All but two of the studies used questionnaires to assess physical activity, with the majority of studies using the IPAQ-short questionnaire. The remaining studies used accelerometers. The percentage of participants who either were or were not meeting the physical activity recommendations was the most commonly reported outcome variable, with the percentage of participants meeting the recommendations ranging from 7 % to 96 % across studies and countries. Conclusions: The included studies showed substantial variation in the assessment methods, reported outcome variables and, consequently, the presented physical activity levels. Because of this, absolute population levels of physical activity in European adults are currently unknown. However, when ranking countries, Ireland, Italy, Malta, Portugal, and Spain generally appear to be among the less active countries. Objective data of adults across Europe is currently limited. These findings highlight the need for standardisation of the measurement methods, as well as cross-European monitoring of physical activity levels

    Rheumatoid arthritis - treatment: 180. Utility of Body Weight Classified Low-Dose Leflunomide in Japanese Rheumatoid Arthritis

    Get PDF
    Background: In Japan, more than 20 rheumatoid arthritis (RA) patients died of interstitial pneumonia (IP) caused by leflunomide (LEF) were reported, but many of them were considered as the victims of opportunistic infection currently. In this paper, efficacy and safety of low-dose LEF classified by body weight (BW) were studied. Methods: Fifty-nine RA patients were started to administrate LEF from July 2007 to July 2009. Among them, 25 patients were excluded because of the combination with tacrolimus, and medication modification within 3 months before LEF. Remaining 34 RA patients administered 20 to 50 mg/week of LEF were followed up for 1 year and enrolled in this study. Dose of LEF was classified by BW (50 mg/week for over 50 kg, 40 mg/week for 40 to 50 kg and 20 to 30 mg/week for under 40 kg). The average age and RA duration of enrolled patients were 55.5 years old and 10.2 years. Prednisolone (PSL), methotrexate (MTX) and etanercept were used in 23, 28 and 2 patients, respectively. In case of insufficient response or adverse effect, dosage change or discontinuance of LEF were considered. Failure was defined as dosages up of PSL and MTX, or dosages down or discontinuance of LEF. Last observation carried forward method was used for the evaluation of failed patients at 1 year. Results: At 1 year after LEF start, good/ moderate/ no response assessed by the European League Against Rheumatism (EULAR) response criteria using Disease Activity Score, including a 28-joint count (DAS28)-C reactive protein (CRP) were showed in 14/ 10/ 10 patients, respectively. The dosage changes of LEF at 1 year were dosage up: 10, same dosage: 5, dosage down: 8 and discontinuance: 11 patients. The survival rate of patients in this study was 23.5% (24 patients failed) but actual LEF continuous rate was 67.6% (11 patients discontinued) at 1 year. The major reason of failure was liver dysfunction, and pneumocystis pneumonia was occurred in 1 patient resulted in full recovery. One patient died of sepsis caused by decubitus ulcer infection. DAS28-CRP score was decreased from 3.9 to 2.7 significantly. Although CRP was decreased from 1.50 to 0.93 mg/dl, it wasn't significant. Matrix metalloproteinase (MMP)-3 was decreased from 220.0 to 174.2 ng/ml significantly. Glutamate pyruvate transaminase (GPT) was increased from 19 to 35 U/l and number of leukocyte was decreased from 7832 to 6271 significantly. DAS28-CRP, CRP, and MMP-3 were improved significantly with MTX, although they weren't without MTX. Increase of GPT and leukopenia were seen significantly with MTX, although they weren't without MTX. Conclusions: It was reported that the risks of IP caused by LEF in Japanese RA patients were past IP history, loading dose administration and low BW. Addition of low-dose LEF is a potent safe alternative for the patients showing unsatisfactory response to current medicines, but need to pay attention for liver function and infection caused by leukopenia, especially with MTX. Disclosure statement: The authors have declared no conflicts of interes

    An exploration of the relationship between educational background and the coaching behaviours and practice activities of professional youth soccer coaches

    Get PDF
    This paper is closed access until 12 December 2019.Background and purpose: Despite the proliferation in recent years of higher education establishments offering tertiary-level study in the field of sports coaching, there is a lack of research into the impact of such courses on coaching practice. The behaviours employed and activities used by coaches during practice sessions is an area where one might expect to see such impact, indeed certain studies have tentatively noted the educational qualifications of coaches and suggested that this may play a role in the application of behaviours more aligned with player learning. The purpose of this study was therefore to compare youth soccer coaches with and without tertiary-level qualifications, examining their coaching behaviours and practice activities. Method: The participants were 10 male professional youth soccer coaches aged 24–55 with an average of 13 years coaching experience. Five of the coaches had completed undergraduate degree courses related to sport coaching. All of the coaches worked with players aged under 9 to under 18 in the youth academy of an English professional soccer club. Systematic observation of coach behaviour and practice activities was carried out using the Coach Analysis and Intervention System (Cushion et al. 2012), while follow-up interviews were used to elicit the coaches’ perceptions of, and rationale for, their behaviour. Findings: The observation data showed that graduate coaches used significantly more divergent questioning than non-graduate coaches, while the interview data revealed a general trend for graduate coaches to show greater self-awareness of behaviours and changes in behaviour between practice types. Graduate coaches also provided more comprehensive rationales, for example, seeing silence as a means of facilitating player decision-making as well as for observation. In contrast to previous research, sessions featured a higher proportion of playing form than training form activities and at over 20% of session duration, the ‘other’ practice state was a prominent feature of contact time with players. While some coaches saw ‘other’ as wasted time, graduate coaches identified this as an opportunity for group discussion and social interaction. The study adds to existing data about coach behaviours and practice activities, providing evidence that education background may indeed influence coaching practice
    corecore