1,027 research outputs found
Portfolio choice and investor preferences: A semi-parametric approach based on risk horizon
The paper proposes an innovative framework for characterizing investors' behavior in portfolio selection. The approach is based on the realistic perspective of unknown investors' utility and incomplete information on returns distribution. Using a four-moment generalization of the Chebyshev inequality, an intuitive risk measure, risk horizon, is introduced with reference to the speed of convergence of a portfolio's mean return to its expectation. Empirical implementation provides evidence on the consistency of the approach with standard portfolio criteria such as, among others, the Sharpe ratio, a shortfall probability decay-rate optimization and a general class of flexible three-parameter utility functions
Office and ambulatory blood pressure control with a fixed-dose combination of candesartan and hydrochlorothiazide in previously uncontrolled hypertensive patients: results of CHILI CU Soon
Thomas Mengden1, Reinhold Hübner2, Peter Bramlage31Kerckhoff-Klinik GmbH, Bad Nauheim, 2Takeda Pharma GmbH, Aachen, 3Institut für Kardiovaskuläre Pharmakologie und Epidemiologie, Mahlow, GermanyBackground: Fixed-dose combinations of candesartan 32 mg and hydrochlorothiazide (HCTZ) have been shown to be effective in clinical trials. Upon market entry we conducted a noninterventional study to document the safety and effectiveness of this fixed-dose combination in an unselected population in primary care and to compare blood pressure (BP) values obtained during office measurement (OBPM) with ambulatory blood pressure measurement (ABPM).Methods: CHILI CU Soon was a prospective, noninterventional, noncontrolled, open-label, multicenter study with a follow-up of at least 10 weeks. High-risk patients aged ≥18 years with previously uncontrolled hypertension were started on candesartan 32 mg in a fixed-dose combination with either 12.5 mg or 25 mg HCTZ. OBPM and ABPM reduction and adverse events were documented.Results: A total of 4131 patients (52.8% male) with a mean age of 63.0 ± 11.0 years were included. BP was 162.1 ± 14.8/94.7 ± 9.2 mmHg during office visits at baseline. After 10 weeks of candesartan 32 mg/12.5 mg or 25 mg HCTZ, mean BP had lowered to 131.7 ± 10.5/80.0 ± 6.6 mmHg (P < 0.0001 for both comparisons). BP reduction was comparable irrespective of prior or concomitant medication. In patients for whom physicians regarded an ABPM to be necessary (because of suspected noncontrol over 24 hours), ABP at baseline was 158.2/93.7 mmHg during the day and 141.8/85.2 mmHg during the night. At the last visit, BP had significantly reduced to 133.6/80.0 mmHg and 121.0/72.3 mmHg, respectively, resulting in 20.8% being normotensive over 24 hours (<130/80 mmHg). The correlation between OBPM and ABPM was good (r = 0.589 for systolic BP and r = 0.389 for diastolic BP during the day). Of those who were normotensive upon OBPM, 35.1% had high ABPM during the day, 49.3% were nondippers, and 3.4% were inverted dippers. Forty-nine adverse events (1.19%) were reported, of which seven (0.17%) were regarded as serious.Conclusion: Candesartan 32 mg in a fixed-dose combination with either 12.5 mg or 25 mg HCTZ is safe and effective for further BP lowering irrespective of prior antihypertensive drug class not being able to control BP.Keywords: ambulatory blood pressure, office blood pressure, normalization, respons
Modelling The Digital Twin For Data-Driven Product Development - A Literature Review
Due to advanced connectivity and increasing distribution of product-service, more and more data is available from the products used and produced. Scientific publications often describe that this product data can be applied in product development to make it more efficient and that the digital twin can play a central role in data provision and interoperability. However, less attention is paid to how the digital twin should be designed for this purpose and how it should be adequately modelled for these use cases. Therefore, this paper presents a structured literature review to analyse which methods are already described in science to model digital twins in a target-oriented way for use cases of data-driven product development. Not only are the procedures interesting, but also the type of digital twin for which they are intended and whether they describe the procedure at the level of a rough macrostructure or detailed microstructure
Operating Power Grids with Few Flow Control Buses
Future power grids will offer enhanced controllability due to the increased
availability of power flow control units (FACTS). As the installation of
control units in the grid is an expensive investment, we are interested in
using few controllers to achieve high controllability. In particular, two
questions arise: How many flow control buses are necessary to obtain globally
optimal power flows? And if fewer flow control buses are available, what can we
achieve with them? Using steady state IEEE benchmark data sets, we explore
experimentally that already a small number of controllers placed at certain
grid buses suffices to achieve globally optimal power flows. We present a
graph-theoretic explanation for this behavior. To answer the second question we
perform a set of experiments that explore the existence and costs of feasible
power flow solutions at increased loads with respect to the number of flow
control buses in the grid. We observe that adding a small number of flow
control buses reduces the flow costs and extends the existence of feasible
solutions at increased load.Comment: extended version of an ACM e-Energy 2015 poster/workshop pape
Hydrogel based protein biochip for parallel detection of biomarkers for diagnosis of a Systemic Inflammatory Response Syndrome (SIRS) in human serum
The Systemic Inflammatory Response Syndrome (SIRS), a sepsis related inflammatory state, is a self-defense mechanism against specific and nonspecific stimuli. The six most extensively studied inflammatory biomarkers for the clinical diagnosis of SIRS are interleukin 4 (hIL-4), interleukin 6 (hIL-6), interleukin 10 (hIL-10), tumor necrosis factor alpha (hTNF-a), interferon gamma (hIFN-gamma) and procalcitonin (hPCT). These biomarkers are naturally present (but usually only at low concentration) in SIRS infected patients [1, 2] and thus the development of a highly sensitive detection method is of major clinical interest. However, the existing analytical techniques are lacking in required analytical sensitivity and parallel determination of these biomarkers. We developed a fast, easy and cost-efficient protein microarray biochip where the capture molecules are attached on hydrogel spots, enabling SIRS diagnosis by parallel detection of these six clinically relevant biomarkers with a sample volume of 25 mu l. With our hydrogel based protein microarray biochip we achieved a limit of detection for hIL-4 of 75.2 pg/ml, for hIL-6 of 45.1 pg/ml, for hIL-10 of 71.5 pg/ml, for hTNF-alpha of 56.7 pg/ml, for IFN-gamma of 46.4 pg/ml and for hPCT of 1.1 ng/ml in spiked human serum demonstrating sufficient sensitivity for clinical usage. Additionally, we demonstrated successful detection of two relevant SIRS biomarkers in clinical patient samples with a turnaround time of the complete analysis from sample-to-answer in less than 200 minutes
Uniform documentation of measures in cases of MRSA – an important step towards improving the quality of treatment
The basis for the management and documentation of multiresistant organisms (MRO) in medical facilities in Germany are the Infection Protection Act (IPA) and the recommendations given by the Commission for Hospital Hygiene and Infection Prevention at the Robert Koch Institute (KRINKO)
Open-source image reconstruction of super-resolution structured illumination microscopy data in ImageJ
Müller M, Mönkemöller V, Hennig S, Hübner W, Huser T. Open-source image reconstruction of super-resolution structured illumination microscopy data in ImageJ. Nature Communications. 2016;7(1): 10980
Data-driven Prediction of Internal Turbulences in Production Using Synthetic Data
Production planning and control are characterized by unplanned events or so-called turbulences. Turbulences can be external, originating outside the company (e.g., delayed delivery by a supplier), or internal, originating within the company (e.g., failures of production and intralogistics resources). Turbulences can have far-reaching consequences for companies and their customers, such as delivery delays due to process delays. For target-optimized handling of turbulences in production, forecasting methods incorporating process data in combination with the use of existing flexibility corridors of flexible production systems offer great potential. Probabilistic, data-driven forecasting methods allow determining the corresponding probabilities of potential turbulences. However, a parallel application of different forecasting methods is required to identify an appropriate one for the specific application. This requires a large database, which often is unavailable and, therefore, must be created first. A simulation-based approach to generate synthetic data is used and validated to create the necessary database of input parameters for the prediction of internal turbulences. To this end, a minimal system for conducting simulation experiments on turbulence scenarios was developed and implemented. A multi-method simulation of the minimal system synthetically generates the required process data, using agent-based modeling for the autonomously controlled system elements and event-based modeling for the stochastic turbulence events. Based on this generated synthetic data and the variation of the input parameters in the forecast, a comparative study of data-driven probabilistic forecasting methods was conducted using a data analytics tool. Forecasting methods of different types (including regression, Bayesian models, nonlinear models, decision trees, ensemble, deep learning) were analyzed in terms of prediction quality, standard deviation, and computation time. This resulted in the identification of appropriate forecasting methods, and required input parameters for the considered turbulences
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