308 research outputs found

    Spray combustion experiments and numerical predictions

    Get PDF
    The next generation of commercial aircraft will include turbofan engines with performance significantly better than those in the current fleet. Control of particulate and gaseous emissions will also be an integral part of the engine design criteria. These performance and emission requirements present a technical challenge for the combustor: control of the fuel and air mixing and control of the local stoichiometry will have to be maintained much more rigorously than with combustors in current production. A better understanding of the flow physics of liquid fuel spray combustion is necessary. This paper describes recent experiments on spray combustion where detailed measurements of the spray characteristics were made, including local drop-size distributions and velocities. Also, an advanced combustor CFD code has been under development and predictions from this code are compared with experimental results. Studies such as these will provide information to the advanced combustor designer on fuel spray quality and mixing effectiveness. Validation of new fast, robust, and efficient CFD codes will also enable the combustor designer to use them as additional design tools for optimization of combustor concepts for the next generation of aircraft engines

    Positive Psychology Couple Schema Therapy: A new model of couple therapy focusing on reigniting couple attraction via schema therapy and positive psychology

    Get PDF
    Introduction: There is growing evidence indicating schema modes influences emotional and behavioural response in couple interaction which affects relationship satisfaction. Thus, identifying dominant schema modes is important for effective couple therapy. Objective: A two-stage positive psychology couple schema therapy, which takes into account the influences of schema and schema modes on couple attraction and dysfunctional conflict resolution style in couples, is proposed. Method: This article describes a case study applying positive psychology couple schema therapy. The first stage of this couple therapy involves identifying the schema mode of each partner, rescript significant childhood experiences, helping each partner to meet the unmet childhood needs and strengthening healthy adult mode. The second stage of the therapy incorporates positive psychology and collaborative therapy to help couples identify and support each other’s positive interests, values and dreams, thus enhancing couple attraction and relationship. Conclusion: Positive psychology couple schema therapy was able to help couples heal childhood unmet needs and reinforce couple attraction

    Spray Combustion Experiments and Numerical Predictions

    Get PDF
    The next generation of commercial aircraft will include turbofan engines with performances significantly better than those in the current fleet. Control of particulate and gaseous emissions will also be an integral part of the engine design criteria. These performance and emission requirements present a technical challenge for the combustor: control of the fuel and air mixing and control of the local stoichiometry will have to be maintained much more rigorously than combustors in current production. A better understanding of the flow physics of liquid fuel spray combustion is necessary. This presentation describes recent experiments on spray combustion where detailed measurements of the spray characteristics were made, including local drop-size distributions and velocities. In addition, an advanced combustor CFD code has been under development and predictions from this code are presented and compared with measurements. Studies such as these will provide information to the advanced combustor designer on fuel spray quality and mixing effectiveness. Validation of new fast, robust, and efficient CFD codes will also enable the combustor designer to use them as valuable design tools for optimization of combustor concepts for the next generation of aircraft engines

    Childhood Learning Disabilities and Atypical Dementia: A Retrospective Chart Review

    Get PDF
    Objective To further our understanding of the association between self-reported childhood learning disabilities (LDs) and atypical dementia phenotypes (Atypical Dementia), including logopenic primary progressive aphasia (L-PPA), Posterior Cortical Atrophy (PCA), and Dysexecutive-type Alzheimer’s Disease (AD). Methods This retrospective case series analysis of 678 comprehensive neuropsychological assessments compared rates of self-reported LD between dementia patients diagnosed with Typical AD and those diagnosed with Atypical Dementia. 105 cases with neuroimaging or CSF data available and at least one neurology follow-up were identified as having been diagnosed by the neuropsychologist with any form of neurodegenerative dementia. These cases were subject to a consensus diagnostic process among three dementia experts using validated clinical criteria for AD and PPA. LD was considered Probable if two or more statements consistent with prior LD were documented within the Social and Developmental History of the initial neuropsychological evaluation. Results 85 subjects (Typical AD n=68, Atypical AD n=17) were included in the final analysis. In logistic regression models adjusted for age, gender, handedness, education and symptom duration, patients with Probable LD, compared to patients without Probable LD, were significantly more likely to be diagnosed with Atypical Dementia vs. Typical AD (OR 13.1, 95% CI 1.3-128.4). All three of the L-PPA cases reporting a childhood LD endorsed childhood difficulty with language. By contrast, both PCA cases reporting Probable childhood LD endorsed difficulty with attention and/or math. Conclusions In people who develop dementia, childhood LD may predispose to atypical phenotypes. Future studies are required to confirm whether atypical neurodevelopment predisposes to regional-specific neuropathology in AD and other dementias

    What Predicts Mortality in Essential Tremor? A Prospective, Longitudinal Study of Elders

    Get PDF
    Objective: Essential tremor (ET) is among the most common neurologic diseases. Although in the past it was considered a benign condition, recent research has demonstrated increased risk of mortality. To date, however, no studies have examined predictors of mortality in ET.Methods: In a longitudinal, prospective study of 141 elders with ET, we used Cox proportional-hazards models to estimate hazard ratios (HRs) for death.Results: The mean baseline age was 81.1 ± 8.8 years. During the follow-up interval, 27 (19.1%) died. Average time from baseline to death was 12.3 ± 8.7 months (range = 0.3–31.2). In univariate Cox regression models, older age (HR = 1.16, p < 0.001), lower Montreal Cognitive Assessment score (HR = 0.88, p = 0.004), higher Clinical Dementia Rating (CDR) score (HR = 4.53, p < 0.001), higher score on the Geriatric Depression scale (GDS) (HR = 1.07, p = 0.048), less balance confidence (HR = 0.98, p = 0.006), more falls (HR = 1.11, p = 0.003), and more tandem mis-steps (HR = 1.53, p = 0.004) were associated with increased risk of mortality. In the final multivariate Cox model, older age (HR = 1.14, p = 0.005), higher CDR score (HR = 3.80, p = 0.002) and higher GDS (HR = 1.11, p = 0.01) were independently associated with increased risk of mortality.Conclusions: This study highlights several independent predictors of mortality in elderly ET; clinicians should consider screening for depressive symptoms, assessing cognition and tracking CDR scores, and assessing balance while evaluating patients with ET
    corecore