1,395 research outputs found

    Direct EIT Reconstructions of Complex Admittivities on a Chest-Shaped Domain in 2-D

    Get PDF
    Electrical impedance tomography (EIT) is a medical imaging technique in which current is applied on electrodes on the surface of the body, the resulting voltage is measured, and an inverse problem is solved to recover the conductivity and/or permittivity in the interior. Images are then formed from the reconstructed conductivity and permittivity distributions. In the 2-D geometry, EIT is clinically useful for chest imaging. In this work, an implementation of a D-bar method for complex admittivities on a general 2-D domain is presented. In particular, reconstructions are computed on a chest-shaped domain for several realistic phantoms including a simulated pneumothorax, hyperinflation, and pleural effusion. The method demonstrates robustness in the presence of noise. Reconstructions from trigonometric and pairwise current injection patterns are included

    Incorporating a Spatial Prior into Nonlinear D-Bar EIT imaging for Complex Admittivities

    Get PDF
    Electrical Impedance Tomography (EIT) aims to recover the internal conductivity and permittivity distributions of a body from electrical measurements taken on electrodes on the surface of the body. The reconstruction task is a severely ill-posed nonlinear inverse problem that is highly sensitive to measurement noise and modeling errors. Regularized D-bar methods have shown great promise in producing noise-robust algorithms by employing a low-pass filtering of nonlinear (nonphysical) Fourier transform data specific to the EIT problem. Including prior data with the approximate locations of major organ boundaries in the scattering transform provides a means of extending the radius of the low-pass filter to include higher frequency components in the reconstruction, in particular, features that are known with high confidence. This information is additionally included in the system of D-bar equations with an independent regularization parameter from that of the extended scattering transform. In this paper, this approach is used in the 2-D D-bar method for admittivity (conductivity as well as permittivity) EIT imaging. Noise-robust reconstructions are presented for simulated EIT data on chest-shaped phantoms with a simulated pneumothorax and pleural effusion. No assumption of the pathology is used in the construction of the prior, yet the method still produces significant enhancements of the underlying pathology (pneumothorax or pleural effusion) even in the presence of strong noise.Comment: 18 pages, 10 figure

    Children Of A Lesser God: Reconceptualizing Race In Immigration Law

    Get PDF
    The increased public exposure to the experiences of Latinx unaccompanied children seeking entry at the United States southern border has revealed the lived reality of the nation’s pernicious immigration laws. The harrowing experiences of unaccompanied children are amplified by their interaction with a legal system plagued by a legacy of systemic racism and sustained racial caste. While immigration law currently affords minimal legal protections for these children, in application, the law continues to fall egregiously short of providing for the safety of unaccompanied children. Though critics have long attested to the legal system’s neglect of unaccompanied children, subsequent legal analysis has overlooked the intersectional role of race as it pertains to their attempts to navigate entry. This Article uses the concept of racialization to explore the legal treatment of Latinx unaccompanied children as they navigate entry to the United States. This Article demonstrates that the legal framework creates structural inequality for Latinx unaccompanied children through a concept known as “adultification.” Further, racist social and political narratives are incorporated into the law which contribute to the racialization of Latinx unaccompanied children and challenges the very vulnerability that lies at the foundation of the legal protections available for children. The Article concludes with a proposed intersectional vulnerability framework that reconceptualizes race and strengthens the rights and protections of unaccompanied children

    Medición de las condiciones habitacionales: una propuesta metodológica para analizar desigualdades inter e intraterritorios urbanos

    Get PDF
    La medición de las condiciones habitacionales de un territorio resulta de especial interés para la implementación de políticas públicas. Los métodos tradicionales se concentran en la medición de los déficits y dejan de lado aquella parte de la población que se encuentra cerca del umbral. Con base en propuestas específicas, estándares de organismos internacionales, legislación nacional y la importante participación de especialistas, en este estudio se genera una metodología cuantitativa, que evita esa pérdida de información al incluir a toda la población de un territorio, asignándole un puntaje a cada persona de acuerdo a las características del hogar que habita. Para validar la propuesta, se presenta una aplicación con datos de Argentina, donde se constata su versatilidad, dado que permite detectar problemáticas particulares en cada dimensión, y también consigue analizar el nivel promedio, la distribución intra e interterritorios y la pérdida de bienestar por desigualdad.The measurement of the housing conditions of a territory is particularly important for the implementation of public policies. Traditional methods focus on the measurement of deficits and leave aside that part of the population which is closer to the threshold. Based on specific proposals, the standards of international organizations, national legislation, and a significant participation of specialists, this study proposes a quantitative methodology, which avoids said loss of information by including the entire population of a territory, assigning a score to each person according to the characteristics of the household they live in. To validate this proposal, we present an application with data from Argentina, where its versatility is verified given that it allows for the detection of issues in each dimension while also getting to analyze the average level, the intra and interterritorial distribution, and the welfare loss due to inequality.Fil: Actis Di Pasquale, Eugenio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina

    Evaluation of the Primary Care Mental Health Specialist role: Final Report

    Get PDF
    This report details an evaluation to assess the impact of the new primary care mental health specialist (PCMHS) role in Kent and Medway. The evaluation was undertaken by the Centre for Health Services Studies (CHSS) at the University of Kent and was conducted June 2013 to December 2014. The evaluation was commissioned by NHS Kent and Medway and supported by Kent and Medway Commissioning Support. The evaluation encompasses six CCG areas across Kent and Medway, with 13 PCMHS employed in these areas (see Table 1-1 for breakdown). The number of posts per CCG is dependent on the amount CCGs invest (roughly equating to population size), rather than prevalence of illness. The PCMHS have been seconded from Kent and Medway NHS and Social Care Partnership Trust (KMPT) for the duration of the pilot, and are either community psychiatric nurses (CPN) or occupational therapists (OT) by profession. The majority of PCMHS are hosted by a voluntary organisation (mcch); three are hosted by GP practices and two by a community Interest Company, Invicta CIC. The main objectives of the evaluation are: 1. To assess the impact on patients by capturing their experience of the service; 2. To assess the impact by capturing experiences of those delivering the service (i.e., PCMHS); 3. To assess the impact by capturing experiences of other professions who work alongside the service (i.e., mental health professionals in secondary care, GPs); 4. To assess the economic cost of the new service via a unit cost analysis

    Robust Computation in 2D Absolute EIT (A-EIT) Using D-Bar Methods with the “EXP” Approximation

    Get PDF
    Objective Absolute images have important applications in medical Electrical Impedance Tomography (EIT) imaging, but the traditional minimization and statistical based computations are very sensitive to modeling errors and noise. In this paper, it is demonstrated that D-bar reconstruction methods for absolute EIT are robust to such errors. Approach The effects of errors in domain shape and electrode placement on absolute images computed with 2-D D-bar reconstruction algorithms are studied on experimental data. Main Results It is demonstrated with tank data from several EIT systems that these methods are quite robust to such modeling errors, and furthermore the artefacts arising from such modeling errors are similar to those occurring in classic time-difference EIT imaging. Significance This study is promising for clinical applications where absolute EIT images are desirable, but previously thought impossible

    Impact of Financial Incentives on Alcohol Consumption Recording in Primary Health Care Among Adults with Schizophrenia and Other Psychoses:A Cross-Sectional and Retrospective Cohort Study

    Get PDF
    Aims: Lack of financial incentive is a frequently cited barrier to alcohol screening in primary care. The Quality and Outcomes Framework (QOF) pay for performance scheme has reimbursed UK primary care practices for alcohol screening in people with schizophrenia since April 2011. This study aimed to determine the impact of financial incentives on alcohol screening by comparing rates of alcohol recording in people with versus those without schizophrenia between 2000 and 2013. Methods: Cross-sectional and retrospective cohort study. Alcohol data were extracted from The Health Improvement Network (THIN) database of UK primary care records using (a) Read Codes for level of alcohol consumption, (b) continuous measures of drinking (e.g. units a week) and (c) Read Codes for types of screening test. Results: A total of 14,860 individuals (54% (8068) men and 46% (6792) women) from 409 general practices aged 18–99 years with schizophrenia were identified during April 2011–March 2013. Of these, 11,585 (78%) had an alcohol record, of which 99% (8150/8257) of Read Codes for level of consumption were eligible for recompense in the QOF. There was an 839% increase in alcohol recording among people with schizophrenia over the 13-year period (rate ratio per annum increase 1.19 (95% CI 1.18–1.20)) compared with a 62% increase among people without a severe mental illness (rate ratio per annum increase 1.04 (95% CI 1.03–1.05)). Conclusion: Financial incentives offered by the QOF appear to have a substantial impact on alcohol screening among people with schizophrenia in UK primary care. Short summary: Alcohol screening among people with schizophrenia increased dramatically in primary health care following the introduction of the UK pay for performance incentive scheme (Quality and Outcomes Framework) for severe mental illness, with an 839% rise (>8-fold increase) compared with a 62% increase among people without a over the 13-year study period (2000–2013)

    Making connections and promoting the profession: social media use by World Federation of Occupational Therapy member organisations

    Get PDF
    BACKGROUND: World Federation of Occupational Therapists (WFOT) member organisations comprise 77 national occupational therapy organisations across the world. Each national organisation interacts with its members and the public using diverse methods. Increasingly, national organisations are broadening their communication methods. OBJECTIVE: The objective of this study was to examine if and how occupational therapy organisations are using social media for communication, and if so, the types of concerns or barriers they experience and what role they anticipate social media might play in the near future. METHODS: An online survey was developed; 57 of 77 WFOT member organisations responded. FINDINGS: This study identified that WFOT national organisations are using social media, to varying degrees, with or without an individual formally assigned to manage social media. Respondents reported that they used social media to: communicate with members, promote the organisation and promote the profession. Commonly expressed needs included assistance with guide- lines for ethical social media use, developing technical expertise, and recognition of limits of time and competing priorities. Recommendations arising from this research are at the global, national, local and individual levels and incorporate active dissemination and pure diffusion approaches. Taking steps to increase the use of social media could indirectly impact occu- pational therapy practice through enhancing organisations’ abilities to support practitioners to enhance their practice. LIMITATIONS AND RECOMENDATIONS FOR FURTHER RESEARCH: Although 57% of WFOT member organisations returned usable responses, there may be some additional perspectives that were not captured. It would be helpful to contact non-responding organisations to explore their social media use and plans. Further research could examine how future initiatives put in place by WFOT impact social media use by member organisations.Published versio

    Summer to winter variability in the step counts of normal weight and overweight adults living in the UK

    Get PDF
    BACKGROUND: This study investigated whether pedometer-determined activity varies between summer and winter in normal-weight and overweight adults. METHODS: Forty-five normal-weight (58% female, age = 39.1 ± 12.4 years, BMI = 22.2 ± 2.1 kg/m2) and 51 overweight (49% female, age = 42.1 ± 12.5 years, BMI = 29.3 ± 4.5 kg/m2) participants completed a within-subject biseasonal pedometer study. All participants completed 2 4-week monitoring periods; 1 period in the summer and 1 period the following winter. Changes in step counts across seasons were calculated and compared for the 2 BMI groups. RESULTS: Both BMI groups reported significant summer to winter reductions in step counts, with the magnitude of change being significantly greater in the normal-weight group (–1737 ± 2201 versus –781 ± 1673 steps/day, P = .02). Winter step counts did not differ significantly between the 2 groups (9250 ± 2845 versus 8974 ± 2709 steps/day, P = .63), whereas the normal-weight group reported a significantly higher mean daily step count in the summer (10986 ± 2858 versus 9755 ± 2874 steps/day, P = .04). CONCLUSION: Both normal-weight and overweight individuals experienced a reduction in step counts between summer and winter; however, normal-weight individuals appear more susceptible to winter decreases in ambulatory activity, with the greatest seasonal change occurring on Sundays. Effective physical activity policies should be seasonally tailored to provide opportunities to encourage individuals to be more active during the winter, particularly on weekends
    corecore