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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Large-scale gene expression profiling data of bone marrow stromal cells from osteoarthritic donors

Stiehler, Maik, Rauh, Juliane, Bünger, Cody, Jacobi, Angela, Vater, Corina, Schildberg, Theresa, Liebers, Cornelia, Günther, Klaus-Peter, Bretschneider, Henriette 27 January 2017 (has links)
This data article contains data related to the research article entitled, 'in vitro characterization of bone marrow stromal cells from osteoarthritic donors' [1]. Osteoarthritis (OA) represents the main indication for total joint arthroplasty and is one of the most frequent degenerative joint disorders. However, the exact etiology of OA remains unknown. Bone marrow stromal cells (BMSCs) can be easily isolated from bone marrow aspirates and provide an excellent source of progenitor cells. The data shows the identification of pivotal genes and pathways involved in osteoarthritis by comparing gene expression patterns of BMSCs from osteoarthritic versus healthy donors using an array-based approach.
52

Microdialysis Sampling from Wound Fluids Enables Quantitative Assessment of Cytokines, Proteins, and Metabolites Reveals Bone Defect-Specific Molecular Profiles

Förster, Yvonne, Schmidt, Johannes R., Wissenbach, Dirk K., Pfeiffer, Susanne E. M., Baumann, Sven, Hofbauer, Lorenz C., von Bergen, Martin, Kalkhof, Stefan, Rammelt, Stefan 27 January 2017 (has links)
Bone healing involves a variety of different cell types and biological processes. Although certain key molecules have been identified, the molecular interactions of the healing progress are not completely understood. Moreover, a clinical routine for predicting the quality of bone healing after a fracture in an early phase is missing. This is mainly due to a lack of techniques to comprehensively screen for cytokines, growth factors and metabolites at their local site of action. Since all soluble molecules of interest are present in the fracture hematoma, its in-depth assessment could reveal potential markers for the monitoring of bone healing. Here, we describe an approach for sampling and quantification of cytokines and metabolites by using microdialysis, combined with solid phase extractions of proteins from wound fluids. By using a control group with an isolated soft tissue wound, we could reveal several bone defect-specific molecular features. In bone defect dialysates the neutrophil chemoattractants CXCL1, CXCL2 and CXCL3 were quantified with either a higher or earlier response compared to dialysate from soft tissue wound. Moreover, by analyzing downstream adaptions of the cells on protein level and focusing on early immune response, several proteins involved in the immune cell migration and activity could be identified to be specific for the bone defect group, e.g. immune modulators, proteases and their corresponding inhibitors. Additionally, the metabolite screening revealed different profiles between the bone defect group and the control group. In summary, we identified potential biomarkers to indicate imbalanced healing progress on all levels of analysis.
53

Why do family doctors prescribe potentially inappropriate medication to elderly patients?

Voigt, Karen, Gottschall, Mandy, Köberlein-Neu, Juliane, Schübel, Jeannine, Quint, Nadine, Bergmann, Antje 06 February 2017 (has links)
Background Based on changes in pharmacokinetics and –dynamics in elderly patients, there are potentially inappropriate medications (PIM) that should be avoided in patients aged ≥ 65 years. Current studies showed prescription rates of PIM between 22.5 and 28.4 % in the primary care setting. The evidence concerning reasons for PIM prescription by FPs is limited. Methods This mixed method study consisted of three research parts: 1) semi-standardized content analysis of patients’ records, 2) qualitative interviews with FPs using a) open questions and b) selected patient-specific case vignettes and 3) qualitative interviews with FPs’ medical assistants. The integration of qualitative interviews was used to explain the quantitative results (triangulation design). PIM were identified according to the German PRISCUS list. Descriptive and multivariate statistical analysis was done using SPSS 22.0. Qualitative content analysis of interviews was used to classify the content of the interviews for indicating pertinent categories. All data were pseudonymously recorded and analyzed. Results Content analysis of 1846 patients’ records and interviews with 7 related FPs were conducted. Elderly patients [n = 1241, mean age: 76, females: 56.6 %] were characterized in average by 8.3 documented chronic diagnosis. 23.9 % of elderly patients received at least one PIM prescription. Sedatives/hypnotics were the most frequent prescribed PIM-drugs (13.7 %). Mental disorders, gender and number of long-term medication were detected as predictors for the probability of a PIM prescription. Common reported reasons for PIM prescription by FPs concerned limited knowledge regarding PIM, limited applicability of PIM lists in daily practice, lack of time, having no alternatives in medication, stronger patient-related factors than age that influence prescription, own bad experiences regarding changes of medication or refusal of following prescriptions of sedative/hypnotics. Conclusions It is essential to see FPs in a complex decision making situation with several influencing factors on their prescribing, including: patient-oriented prioritization, FPs’ experiences in daily practice, FPs’ knowledge regarding existing recommendations and their trust in it and organizational characteristics of FPs’ daily medical practice. These pros and cons of PIM prescription in elderly patients should be considered in FPs’ advanced training.
54

Crystallographic insights into (CH3NH3)3(Bi2I9): a new lead-free hybrid organic–inorganic material as a potential absorber for photovoltaics

Eckhardt, Kai, Bon, Volodymyr, Getzschmann, Jürgen, Grothe, Julia, Wisser, Florian M., Kaskel, Stefan 17 March 2017 (has links)
The crystal structure of a new bismuth-based light-absorbing material for the application in solar cells was determined by single crystal X-ray diffraction for the first time. (CH3NH3)3(Bi2I9) (MBI) is a promising alternative to recently rapidly progressing hybrid organic–inorganic perovskites due to the higher tolerance against water and low toxicity. Single crystal X-ray diffraction provides detailed structural information as an essential prerequisite to gain a fundamental understanding of structure property relationships, while powder diffraction studies demonstrate a high degree of crystallinity in thin films.
55

Fitness and mobility training in patients with Intensive Care Unit-acquired muscle weakness (FITonICU): study protocol for a randomised controlled trial

Mehrholz, Jan, Thomas, Simone, Burridge, Jane H., Schmidt, André, Scheffler, Bettina, Schellin, Ralph, Rückriem, Stefan, Meißner, Daniel, Mehrholz, Katja, Sauter, Wolfgang, Bodechtel, Ulf, Elsner, Bernhard 27 February 2017 (has links)
Background Critical illness myopathy (CIM) and polyneuropathy (CIP) are a common complication of critical illness. Both cause intensive-care-unit-acquired (ICU-acquired) muscle weakness (ICUAW) which increases morbidity and delays rehabilitation and recovery of activities of daily living such as walking ability. Focused physical rehabilitation of people with ICUAW is, therefore, of great importance at both an individual and a societal level. A recent systematic Cochrane review found no randomised controlled trials (RCT), and thus no supporting evidence, for physical rehabilitation interventions for people with defined CIP and CIM to improve activities of daily living. Therefore, the aim of our study is to compare the effects of an additional physiotherapy programme with systematically augmented levels of mobilisation with additional in-bed cycling (as the parallel group) on walking and other activities of daily living.
56

Volumetric HiLo microscopy employing an electrically tunable lens

Philipp, Katrin, Smolarski, André, Koukourakis, Nektarios, Fischer, Andreas, Stürmer, Moritz, Wallrabe, Ulrike, Czarske, Jürgen W. 11 October 2017 (has links)
Electrically tunable lenses exhibit strong potential for fast motion-free axial scanning in a variety of microscopes. However, they also lead to a degradation of the achievable resolution because of aberrations and misalignment between illumination and detection optics that are induced by the scan itself. Additionally, the typically nonlinear relation between actuation voltage and axial displacement leads to over- or under-sampled frame acquisition in most microscopic techniques because of their static depth-of-field. To overcome these limitations, we present an Adaptive-Lens-High-and-Low-frequency (AL-HiLo) microscope that enables volumetric measurements employing an electrically tunable lens. By using speckle-patterned illumination, we ensure stability against aberrations of the electrically tunable lens. Its depth-of-field can be adjusted a-posteriori and hence enables to create flexible scans, which compensates for irregular axial measurement positions. The adaptive HiLo microscope provides an axial scanning range of 1 mm with an axial resolution of about 4 μm and sub-micron lateral resolution over the full scanning range. Proof of concept measurements at home-built specimens as well as zebrafish embryos with reporter gene-driven fluorescence in the thyroid gland are shown.
57

Quantitative Retrieval of Organic Soil Properties from Visible Near-Infrared Shortwave Infrared (Vis-NIR-SWIR) Spectroscopy Using Fractal-Based Feature Extraction.

Liu, Lanfa, Buchroithner, Manfred, Ji, Min, Dong, Yunyun, Zhang, Rongchung 27 March 2017 (has links)
Visible and near-infrared diffuse reflectance spectroscopy has been demonstrated to be a fast and cheap tool for estimating a large number of chemical and physical soil properties, and effective features extracted from spectra are crucial to correlating with these properties. We adopt a novel methodology for feature extraction of soil spectroscopy based on fractal geometry. The spectrum can be divided into multiple segments with different step–window pairs. For each segmented spectral curve, the fractal dimension value was calculated using variation estimators with power indices 0.5, 1.0 and 2.0. Thus, the fractal feature can be generated by multiplying the fractal dimension value with spectral energy. To assess and compare the performance of new generated features, we took advantage of organic soil samples from the large-scale European Land Use/Land Cover Area Frame Survey (LUCAS). Gradient-boosting regression models built using XGBoost library with soil spectral library were developed to estimate N, pH and soil organic carbon (SOC) contents. Features generated by a variogram estimator performed better than two other estimators and the principal component analysis (PCA). The estimation results for SOC were coefficient of determination (R2) = 0.85, root mean square error (RMSE) = 56.7 g/kg, the ratio of percent deviation (RPD) = 2.59; for pH: R2 = 0.82, RMSE = 0.49 g/kg, RPD = 2.31; and for N: R2 = 0.77, RMSE = 3.01 g/kg, RPD = 2.09. Even better results could be achieved when fractal features were combined with PCA components. Fractal features generated by the proposed method can improve estimation accuracies of soil properties and simultaneously maintain the original spectral curve shape.
58

Assessment of Managed Aquifer Recharge through Modeling—A Review

Ringleb, Jana, Stefan, Catalin, Sallwey, Jana 28 March 2017 (has links)
Managed aquifer recharge (MAR) is the purposeful recharge of an aquifer for later recovery or environmental benefits and represents a valuable method for sustainable water resources management. Models can be helpful tools for the assessment of MAR systems. This review encompasses a survey and an analysis of case studies which apply flow and transport models to evaluate MAR. The observed modeling objectives include the planning or optimization of MAR schemes as well as the identification and quantification of geochemical processes during injection, storage and recovery. The water recovery efficiency and the impact of the injected water on the ambient groundwater are further objectives investigated in the reviewed studies. These objectives are mainly solved by using groundwater flow models. Unsaturated flow models, solute transport models, reactive geochemical models as well as water balance models are also frequently applied and often coupled. As each planning step to setup a new MAR facility requires cost and time investment, modeling is used to minimize hazard risks and assess possible constraints of the system such as low recovery efficiency, clogging and geochemical processes.
59

Study of a Particle Based Films Cure Process by High-Frequency Eddy Current Spectroscopy

Patsora, Iryna, Tatarchuk, Dmytro, Heuer, Henning, Hillmann, Susanne 28 March 2017 (has links)
Particle-based films are today an important part of various designs and they are implemented in structures as conductive parts, i.e., conductive paste printing in the manufacture of Li-ion batteries, solar cells or resistive paste printing in IC. Recently, particle based films were also implemented in the 3D printing technique, and are particularly important for use in aircraft, wind power, and the automotive industry when incorporated onto the surface of composite structures for protection against damages caused by a lightning strike. A crucial issue for the lightning protection area is to realize films with high homogeneity of electrical resistance where an in-situ noninvasive method has to be elaborated for quality monitoring to avoid undesirable financial and time costs. In this work the drying process of particle based films was investigated by high-frequency eddy current (HFEC) spectroscopy in order to work out an automated in-situ quality monitoring method with a focus on the electrical resistance of the films. Different types of particle based films deposited on dielectric and carbon fiber reinforced plastic substrates were investigated in the present study and results show that the HFEC method offers a good opportunity to monitor the overall drying process of particle based films. Based on that, an algorithm was developed, allowing prediction of the final electrical resistance of the particle based films throughout the drying process, and was successfully implemented in a prototype system based on the EddyCus® HFEC device platform presented in this work. This prototype is the first solution for a portable system allowing HFEC measurement on huge and uneven surfaces.
60

Analysis of Dominant Process Parameters in Deep-Drawing of Paperboard

Müller, Tobias, Lenske, Alexander, Hauptmann, Marek, Majschak, Jens-Peter 12 June 2018 (has links)
The application of the wrinkle measuring method described in Müller et al. (2017) and the subsequent evaluation algorithm of a range of deep-drawn samples were used to determine the influences and interdependencies of blankholder force, tool temperatures, and drawing height on the formation of wrinkles in paperboard. The main influences were identified and quantitatively evaluated. For the given experimental space, a regression function was derived and validated in further experiments. It was shown that a quadratic regression was superior to the previously used linear regression. The findings were discussed and compared with the results of similar experiments from past publications. Special attention was given to the wrinkles formed and the resulting quality of the formed paperboard cups. The restrictions of the data acquisition from the measuring method that was used and limitations of the model were presented to demonstrate the reliability of the results.

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