245 research outputs found

    Economic evaluation of flexible IGCC plants with integrated membrane reactor modules

    Get PDF
    Integrated Gasification Combined Cycle with embedded membrane reactor modules (IGCC-MR) represents a new technology option for the co-production of electricity and pure hydrogen endowed with enhanced environmental performance capacity. It is an alternative to conventional coaland gas-fired power generation technologies. As a new technology, the IGCC-MR power plant needs to be evaluated in the presence of irreducible regulatory and fuel market uncertainties for the potential deployment of an initial fleet of demonstration plants at the commercial scale. This paper presents the development of a systematic and comprehensive three-step methodological framework to assess the economic value of flexible alternatives in the design and operations of an IGCC-MR plant under the aforementioned sources of uncertainty. The main objective is to demonstrate the potential value enhancements stemming to the long-term economic performance of flexible IGCC-MR project investments, by managing the uncertainty associated with future environmental regulations and fuel costs. The paper provides an overview of promising design flexibility concepts for IGCC-MR power plants and focuses on operational and constructional flexibility. The operational flexibility is realized through the option of a temporary shutdown of the plant with considerations of regulatory and market uncertainties. This option reduces the probability of loss and the downside risk compared to the base case. The constructional flexibility considers installation of a Carbon Capture and Storage (CCS) unit in the plant under three different alternatives: 1) installing CCS in the initial construction phase, 2) retrofitting CCS at a later stage and 3) retrofitting CCS with pre-investment at a later stage. Monte Carlo simulations and financial analysis are used to demonstrate that the most economically advantageous flexibility option is to install CCS in the initial IGCC-MR construction phase

    Economic performance evaluation of flexible centralised and decentralised blue hydrogen production systems design under uncertainty

    Get PDF
    Blue hydrogen is viewed as an important energy vector in a decarbonised global economy, but its large-scale and capital-intensive production displays economic performance vulnerabities in the face of increased market and regulatory uncertainty. This study analyses flexible (modular) blue hydrogen production plant designs and evaluates their effectiveness to enhance economic performance under uncertainty. The novelty of this work lies in the development of a comprehensive techno-economic evaluation framework that considers flexible centralised and decentralised blue hydrogen plant design alternatives in the presence of irreducible uncertainty, whilst explicitly considering the time value of money, economies of scale and learning effects. A case study of centralised and decentralised blue hydrogen production for the transport sector in the San Francisco area is developed to highlight the underlying value of flexibility. The proposed methodological framework considers various blue hydrogen plant designs (fixed, phased, and flexible) and compares them using relevant economic indicators (net present value (NPV), capex, value-at-risk/gain, etc.) through a detailed Monte Carlo simulation framework. Results indicate that flexible centralised hydrogen production yields greater economic value than alternative designs, despite the associated cost-premium of modularity. It is also shown that the value of flexibility increases under greater uncertainty, higher learning rates and weaker economies of scale. Moreover, sensitivity analysis reveals that flexible design remains the preferred investment option over a wide range of market and regulatory conditions except for high initial hydrogen demand. Finally, this study demonstrates that major regulatory and market uncertainties surrounding blue hydrogen production can be effectively managed through the application of flexible engineering system design that protects the investment from major downside risks whilst allowing access to favourable upside opportunities

    The Relationship Between Homework Compliance and Therapy Outcomes: An Updated Meta-Analysis

    Get PDF
    The current study was an updated meta-analysis of manuscripts since the year 2000 examining the effects of homework compliance on treatment outcome. A total of 23 studies encompassing 2,183 subjects were included. Results indicated a significant relationship between homework compliance and treatment outcome suggesting a small to medium effect (r = .26; 95% CI = .19–.33). Moderator analyses were conducted to determine the differential effect size of homework on treatment outcome by target symptoms (e.g., depression; anxiety), source of homework rating (e.g., client; therapist), timing of homework rating (e.g., retroactive vs. contemporaneous), and type of homework rating (e.g., Likert; total homeworks completed). Results indicated that effect sizes were robust across target symptoms, but differed by source of homework rating, timing of homework rating, and type of homework rating. Specifically, studies utilizing combined client and therapist ratings of compliance had significantly higher mean effect size relative to those using therapist only assessments and those using objective assessments. Further, studies that rated the percentage of homeworks completed had a significantly lower mean effect size compared to studies using Likert ratings, and retroactive assessments had higher effect size than contemporaneous assessments

    The College News, 1918-05-23, Vol. 04, No. 27

    Get PDF
    Bryn Mawr College student newspaper. Merged with The Haverford News in 1968 to form the Bi-college News (with various titles from 1968 on). Published weekly (except holidays) during the academic year

    A cohort study of 30 day mortality after NON-EMERGENCY surgery in a COVID-19 cold site

    Get PDF
    BACKGROUND: Two million non-emergency surgeries are being cancelled globally every week due to the COVID-19 pandemic, which will have a major impact on patients and healthcare systems. METHODS: During the peak of the pandemic in the United Kingdom, we set up a multicentre cancer network amongst 14 National Health Service institutions, performing urological, thoracic, gynaecological and general surgical urgent and cancer operations at a central COVID-19 cold site. This is a cohort study of 500 consecutive patients undergoing surgery in this network. The primary outcome was 30-day mortality from COVID-19. Secondary outcomes included all-cause mortality and post-operative complications at 30-days. RESULTS: 500 patients underwent surgery with median age 62.5 (IQR 51-71). 65% were male, 60% had a known diagnosis of cancer and 61% of surgeries were considered complex or major. No patient died from COVID-19 at 30-days. 30-day all-cause mortality was 3/500 (1%). 10 (2%) patients were diagnosed with COVID-19, 4 (1%) with confirmed laboratory diagnosis and 6 (1%) with probable COVID-19. 33/500 (7%) of patients developed Clavien-Dindo grade 3 or higher complications, with 1/33 (3%) occurring in a patient with COVID-19. CONCLUSION: It is safe to continue cancer and urgent surgery during the COVID-19 pandemic with appropriate service reconfiguration

    Psychodynamic Guided Self-help for Adult Deperssion through the Internet: A Randomised Controlled Trial.

    Get PDF
    Abstract Background and aims: Psychodynamic psychotherapy (PDT) is an effective treatment for major depressive disorder (MDD), but not all clients with MDD can receive psychotherapy. Using the Internet to provide psychodynamic treatments is one way of improving access to psychological treatments for MDD. The aim of this randomised controlled trial was to investigate the efficacy of an Internet-based psychodynamic guided self-help treatment for MDD. Methods: Ninety-two participants who were diagnosed with MDD according to the Mini-International Neuropsychiatric Interview were randomised to treatment or an active control. The treatment consisted of nine treatment modules based on psychodynamic principles with online therapist contact. The active control condition was a structured support intervention and contained psychoeducation and scheduled weekly contacts online. Both interventions lasted for 10 weeks. The primary outcome measure was the Beck Depression Inventory-II (BDI-II). Results: Mixed-effects model analyses of all randomised participants showed that participants receiving Internet-based PDT made large and superior improvements compared with the active control group on the BDI-II (between-group Cohen’s d = 1.11). Treatment effects were maintained at a 10-month follow-up. Conclusions: Internet-based psychodynamic guided self-help is an efficacious treatment for MDD that has the potential to increase accessibility and availability of PDT for MDD

    A mobile phone application for the assessment and management of youth mental health problems in primary care: a randomised controlled trial

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Over 75% of mental health problems begin in adolescence and primary care has been identified as the target setting for mental health intervention by the World Health Organisation. The <it>mobiletype </it>program is a mental health assessment and management mobile phone application which monitors mood, stress, coping strategies, activities, eating, sleeping, exercise patterns, and alcohol and cannabis use at least daily, and transmits this information to general practitioners (GPs) via a secure website in summary format for medical review.</p> <p>Methods</p> <p>We conducted a randomised controlled trial in primary care to examine the mental health benefits of the <it>mobiletype </it>program. Patients aged 14 to 24 years were recruited from rural and metropolitan general practices. GPs identified and referred eligible participants (those with mild or more mental health concerns) who were randomly assigned to either the intervention group (where mood, stress, and daily activities were monitored) or the attention comparison group (where only daily activities were monitored). Both groups self-monitored for 2 to 4 weeks and reviewed the monitoring data with their GP. GPs, participants, and researchers were blind to group allocation at randomisation. Participants completed pre-, post-, and 6-week post-test measures of the Depression, Anxiety, Stress Scale and an Emotional Self Awareness (ESA) Scale.</p> <p>Results</p> <p>Of the 163 participants assessed for eligibility, 118 were randomised and 114 participants were included in analyses (intervention group n = 68, comparison group n = 46). Mixed model analyses revealed a significant group by time interaction on ESA with a medium size of effect suggesting that the <it>mobiletype </it>program significantly increases ESA compared to an attention comparison. There was no significant group by time interaction for depression, anxiety, or stress, but a medium to large significant main effect for time for each of these mental health measures. Post-hoc analyses suggested that participation in the RCT lead to enhanced GP mental health care at pre-test and improved mental health outcomes.</p> <p>Conclusions</p> <p>Monitoring mental health symptoms appears to increase ESA and implementing a mental health program in primary care and providing frequent reminders, clinical resources, and support to GPs substantially improved mental health outcomes for the sample as a whole.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov <a href="http://www.clinicaltrials.gov/ct2/show/NCT00794222">NCT00794222</a>.</p
    corecore