257 research outputs found

    Building a traceable climate model hierarchy with multi-level emulators

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    To study climate change on multi-millennial timescales or to explore a model’s parameter space, efficient models with simplified and parameterised processes are required. However, the reduction in explicitly modelled processes can lead to underestimation of some atmospheric responses that are essential to the understanding of the climate system. While more complex general circulations are available and capable of simulating a more realistic climate, they are too computationally intensive for these purposes. In this work, we propose a multi-level Gaussian emulation technique to efficiently estimate the outputs of steady-state simulations of an expensive atmospheric model in response to changes in boundary forcing. The link between a computationally expensive atmospheric model, PLASIM (Planet Simulator), and a cheaper model, EMBM (energy–moisture balance model), is established through the common boundary condition specified by an ocean model, allowing for information to be propagated from one to the other. This technique allows PLASIM emulators to be built at a low cost. The method is first demonstrated by emulating a scalar summary quantity, the global mean surface air temperature. It is then employed to emulate the dimensionally reduced 2-D surface air temperature field. Even though the two atmospheric models chosen are structurally unrelated, Gaussian process emulators of PLASIM atmospheric variables are successfully constructed using EMBM as a fast approximation. With the extra information gained from the cheap model, the multi-level emulator of PLASIM’s 2-D surface air temperature field is built using only one-third the amount of expensive data required by the normal single-level technique. The constructed emulator is shown to capture 93.2% of the variance across the validation ensemble, with the averaged RMSE of 1.33 °C. Using the method proposed, quantities from PLASIM can be constructed and used to study the effects introduced by PLASIM’s atmosphere

    Health Districts as Quality Improvement Collaboratives and Multi-Jurisdictional Entities

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    Research Objective: The Georgia Public Health PBRN assessed the utility of the Multi-county Health District as a structured Quality Improvement Collaborative (QIC), and as multi jurisdictional entities for purposes of meeting standards for accreditation by the Public Health Accreditation Board. Data Sets and Sources: Data were collected from online surveys followed up with phone interviews or paper surveys to maximize participation. A newly developed clinical care QIC instrument (Schouten et al, 2010) was modified to collect data with a revised focus on QICs for public health. We retained QI culture constructs in the instrument while shifting the focus from healthcare to public health essential services related to accreditation standards. Study Design: Data was collected from a purposeful sample of local public health key informants in Georgia who were identified by the District Directors’ office as local key informants. Invitations Key informants included county and district staff and county board of health members. Analysis: Psychometric testing of the QIC assessment instrument included tests for validity and reliability. Census-based and self-reported demographic characteristics were used to compare responses. Principal Findings: Strong consensus emerged across various constituencies that Districts were critical for local public health to provide essential services. Key opinion leaders from both the rural and non-rural counties agreed that the Districts were important. Conclusion: Regionalization using Georgia Districts has major potential for supporting QI and meeting quality assurance standards associated with accreditation. Implications for Field of PHSSR: Accreditation has the potential to substantially clarify and enhance the role of public health in the 21st century. But local public health agencies, based on small municipality or county populations, are unlikely to possess and sustain capacity to meet the challenges of comprehensive essential services. Regionalization of local public health capacity is a critical emerging issue with the launching of public health accreditation

    Clarifying and Expanding Concepts of Cross-Jurisdictional Sharing: Early Lessons Learned from Conducting QI with Georgia’s Health Districts

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    Research Objective: Assess the legal and organization cultural foundations for Cross-Jurisdictional Sharing (CJS) in support of local public health accreditation and QI in Georgia. Data Sets and Sources: Archival data (primarily state statutes), secondary data from previous qualitative comparative research on Deep South public health organization, secondary data from previous surveys, and oral interviews and written communication. Study Design: Primarily Qualitative design combining ethnographic and participatory research methods. Analysis: Qualitative Content analysis based on predetermined and emergent themes. Principal Findings: Georgia’s Health Districts have emerged as major CJS entities that support delivery of essential services and local public health (LPH) QI and LPH accreditation readiness, driven primarily by local organizational leadership and culture that is facilitated through enabling statutes in contrast to more top-down state-mandating statutes, regulations and directives. Conclusion: Georgia’s use of districts as multi-county public health entities serves as a primary structure for providing local public health services and has become a critical structure to address the looming demands for QI and accreditation, even though the statutes clearly establish the county as the primary local public health entity. Implications for the Field of PHSSR: This CJS structure to facilitate public health QI and accreditation in Georgia illustrates how agency cultures can emerge from local demands for economies of scale, more than formal policies generated at state level. This is a model that could be very important for advancing CJS in other regions of the country

    Comparison of practice based research network based quality improvement technical assistance and evaluation to other ongoing quality improvement efforts for changes in agency culture

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    Abstract Background Public health agencies in the USA are increasingly challenged to adopt Quality Improvement (QI) strategies to enhance performance. Many of the functional and structural barriers to effective use of QI can be found in the organizational culture of public health agencies. The purpose of this study was to assess the impact of public health practice based research network (PBRN) evaluation and technical assistance for QI interventions on the organizational culture of public health agencies in Georgia, USA. Methods An online survey of key informants in Georgia’s districts and county health departments was used to compare perceptions of characteristics of organizational QI culture between PBRN supported QI districts and non-PBRN supported districts before and after the QI interventions. The primary outcomes of concern were number and percentage of reported increases in characteristics of QI culture as measured by key informant responses to items assessing organizational QI practices from a validated instrument on QI Collaboratives. Survey results were analyzed using Multi-level Mixed Effects Logistic Model, which accounts for clustering/nesting. Results Increases in QI organizational culture were consistent for all 10- items on a QI organizational culture survey related to: leadership support, use of data, on-going QI, and team collaboration. Statistically significant odds ratios were calculated for differences in increased QI organizational culture between PBRN-QI supported districts compared to Non-PBRN supported districts for 5 of the 10 items, after adjusting for District clustering of county health departments. Conclusions Agency culture, considered by many QI experts as the main goal of QI, is different than use of specific QI methods, such as Plan-Do-Study-Act (PDSA) cycles or root-cause analyses. The specific use of a QI method does not necessarily reflect culture change. Attempts to measure QI culture are newly emerging. This study documented significant improvements in characteristics of organizational culture and demonstrated the potential of PBRNs to support agency QI activities

    Geographically touring the eastern bloc: British geography, travel cultures and the Cold War

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    This paper considers the role of travel in the generation of geographical knowledge of the eastern bloc by British geographers. Based on oral history and surveys of published work, the paper examines the roles of three kinds of travel experience: individual private travels, tours via state tourist agencies, and tours by academic delegations. Examples are drawn from across the eastern bloc, including the USSR, Poland, Romania, East Germany and Albania. The relationship between travel and publication is addressed, notably within textbooks, and in the Geographical Magazine. The study argues for the extension of accounts of cultures of geographical travel, and seeks to supplement the existing historiography of Cold War geography

    Managing hematological cancer patients during the COVID-19 pandemic:an ESMO-EHA Interdisciplinary Expert Consensus

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    Background: The COVID-19 pandemic has created enormous challenges for the clinical management of patients with hematological malignancies (HMs), raising questions about the optimal care of this patient group. Methods: This consensus manuscript aims at discussing clinical evidence and providing expert advice on statements related to the management of HMs in the COVID-19 pandemic. For this purpose, an international consortium was established including a steering committee, which prepared six working packages addressing significant clinical questions from the COVID-19 diagnosis, treatment, and mitigation strategies to specific HMs management in the pandemic. During a virtual consensus meeting, including global experts and lead by the European Society for Medical Oncology and the European Hematology Association, statements were discussed and voted upon. When a consensus could not be reached, the panel revised statements to develop consensual clinical guidance. Results and conclusion: The expert panel agreed on 33 statements, reflecting a consensus, which will guide clinical decision making for patients with hematological neoplasms during the COVID-19 pandemic.</p

    Thalidomide, dexamethasone and lovastatin with autologous stem cell transplantation as a salvage immunomodulatory therapy in patients with relapsed and refractory multiple myeloma

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    The treatment of patients with multiple myeloma usually includes many drugs including thalidomide, lenalidomide and bortezomib. Lovastatin and other inhibitors of HMG-CoA reductase demonstrated to exhibit antineoplasmatic and proapoptotic properties in numerous in vitro studies involving myeloma cell lines. We treated 91 patients with relapsed or refractory multiple myeloma with thalidomide, dexamethasone and lovastatin (TDL group, 49 patients) or thalidomide and dexamethasone (TD group, 42 patients). A clinical response defined of at least 50% reduction of monoclonal band has been observed in 32% of TD patients and 44% of TDL patients. Prolongation of overall survival and progression-free survival in the TDL group as compared with the TD group has been documented. The TDL regimen was safe and well tolerated. The incidence of side effects was comparable in both groups. Plasma cells have been cultured in vitro with thalidomide and lovastatin to assess the impact of both drugs on the apoptosis rate of plasma cells. In vitro experiments revealed that the combination of thalidomide and lovastatin induced higher apoptosis rate than apoptosis induced by each drug alone. Our results suggest that the addition of lovastatin to the TD regimen may improve the response rate in patients with relapsed or refractory myeloma

    Stock Market Returns, Corporate Governance and Capital Market Equilibrium

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    This paper analyzes why corporate governance matters for stock returns if the stock market prices the underlying managerial agency problem correctly. Our theory assumes that strict corporate governance prevents managers from diverting cash flows, but reduces incentives for managerial effort. In capital market equilibrium, this trade-off has implications for the firm's earnings, stock returns, and managerial ownership, because governance impacts the firm's risk-return structure. In particular, the strictness of corporate governance is negatively related to earnings and positively to β. Various empirical tests with U.S. data using the governance index of Gompers, Ishii, and Metrick (2003) yield results consistent with these predictions

    COVID-19 in cancer patients: clinical characteristics and outcome—an analysis of the LEOSS registry

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    Introduction Since the early SARS-CoV-2 pandemic, cancer patients have been assumed to be at higher risk for severe COVID-19. Here, we present an analysis of cancer patients from the LEOSS (Lean European Open Survey on SARS-CoV-2 Infected Patients) registry to determine whether cancer patients are at higher risk. Patients and methods We retrospectively analyzed a cohort of 435 cancer patients and 2636 non-cancer patients with confirmed SARS-CoV-2 infection, enrolled between March 16 and August 31, 2020. Data on socio-demographics, comorbidities, cancer-related features and infection course were collected. Age-, sex- and comorbidity-adjusted analysis was performed. Primary endpoint was COVID-19-related mortality. Results In total, 435 cancer patients were included in our analysis. Commonest age category was 76–85 years (36.5%), and 40.5% were female. Solid tumors were seen in 59% and lymphoma and leukemia in 17.5% and 11% of patients. Of these, 54% had an active malignancy, and 22% had recently received anti-cancer treatments. At detection of SARS-CoV-2, the majority (62.5%) presented with mild symptoms. Progression to severe COVID-19 was seen in 55% and ICU admission in 27.5%. COVID-19-related mortality rate was 22.5%. Male sex, advanced age, and active malignancy were associated with higher death rates. Comparing cancer and non-cancer patients, age distribution and comorbidity differed significantly, as did mortality (14% vs 22.5%, p value < 0.001). After adjustments for other risk factors, mortality was comparable. Conclusion Comparing cancer and non-cancer patients, outcome of COVID-19 was comparable after adjusting for age, sex, and comorbidity. However, our results emphasize that cancer patients as a group are at higher risk due to advanced age and pre-existing conditions
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