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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.
141

Low mood, visual hallucinations, and falls – heralding the onset of rapidly progressive probable sporadic Creutzfeldt–Jakob disease in a 73-year old: a case report

Klotz, Daniel Martin, Penfold, Rose Sarah 12 June 2018 (has links)
Background Creutzfeldt–Jakob disease is a rare and rapidly fatal neurodegenerative disease. Since clinicians may see only very few cases during their professional career, it is important to be familiar with the clinical presentation and progression, to perform appropriate investigations, and allow for quick diagnosis. Case presentation A 73-year-old British Caucasian woman presented with acute confusion of 2 weeks’ duration on a background of low mood following a recent bereavement. Her symptoms included behavioral change, visual hallucinations, vertigo, and recent falls. She was mildly confused, with left-sided hyperreflexia, a wide-based gait, and intention tremor in her left upper limb. Initial blood tests, computed tomography, and magnetic resonance imaging of her brain showed no significant abnormality. Following admission, she had rapid cognitive decline and developed florid and progressive neurological signs; a diagnosis of prion disease was suspected. A lumbar puncture was performed; cerebrospinal fluid was positive for 14–3-3 protein, real-time quaking-induced conversion, and raised levels of s-100b proteins were detected. An electroencephalogram showed bilateral periodic triphasic waves on a slow background. The diagnosis of probable Creutzfeldt–Jakob disease was made. Conclusions This case report highlights key features in the initial presentation and clinical development of a rare but invariably rapidly progressive and fatal disease. It emphasizes the importance of considering a unifying diagnosis for multifaceted clinical presentations. Although it is very rare, Creutzfeldt–Jakob disease should be considered a diagnosis for a mixed neuropsychiatric presentation, particularly with rapid progressive cognitive decline and development of neurological signs. However, to avoid overlooking early signal change on magnetic resonance imaging, it is important to take diffusion-weighted magnetic resonance imaging for all patients with neuropsychological symptoms. Importantly, early diagnosis also ensures the arrangement of suitable contamination control measures to minimize the risk of infection to health care professionals and other patients.
142

Executive Function Deficits in Seriously Ill Children—Emerging Challenges and Possibilities for Clinical Care

Bluschke, Annet, von der Hagen, Maja, Novotna, Barbara, Roessner, Veit, Beste, Christian 12 June 2018 (has links)
The past years have seen an incredible increase in the quality and success rates of treatments in pediatric medicine. One of the resulting major challenges refers to the management of primary or secondary residual executive function deficits in affected children. These deficits lead to problems in the ability to acquire, understand, and apply abstract and complex knowledge and to plan, direct, and control actions. Executive functions deficits are important to consider because they are highly predictive of functioning in social and academic aspects of daily life. We argue that current clinical practice does not sufficiently account for the complex cognitive processes in this population. This is because widely applied pharmacological interventions only rarely account for the complexity of the underlying neuronal mechanisms and do not fit well into possibly powerful “individualized medicine” approaches. Novel treatment approaches targeting deficits in executive functions in seriously ill children could focus on neuronal oscillations, as these have some specific relations to different aspects of executive function. Importantly, such treatment approaches can be individually tailored to the individuals’ deficits and can be transferred into home-treatment or e-health solutions. These approaches are easy-to-use, can be easily integrated into daily life, and are becoming increasingly cost-effective.
143

Temporal Stability of GPS Transmitter Group Delay Variations

Beer, Susanne, Wanninger, Lambert 12 June 2018 (has links)
The code observable of global navigation satellite systems (GNSS) is influenced by group delay variations (GDV) of transmitter and receiver antennas. For the Global Positioning System (GPS), the variations can sum up to 1 m in the ionosphere-free linear combination and thus can significantly affect precise code applications. The contribution of the GPS transmitters can amount to 0.8 m peak-to-peak over the entire nadir angle range. To verify the assumption of their time-invariance, we determined daily individual satellite GDV for GPS transmitter antennas over a period of more than two years. Dual-frequency observations of globally distributed reference stations and their multipath combination form the basis for our analysis. The resulting GPS GDV are stable on the level of a few centimeters for C1, P2, and for the ionosphere-free linear combination. Our study reveals that the inconsistencies of the GDV of space vehicle number (SVN) 55 with respect to earlier studies are not caused by temporal instabilities, but are rather related to receiver properties.
144

Outdoor air pollution, green space, and cancer incidence in Saxony: a semi-individual cohort study

Datzmann, Thomas, Markevych, Ianna, Trautmann, Freya, Heinrich, Joachim, Schmitt, Jochen, Tesch, Falko 15 June 2018 (has links)
Background There are a few epidemiological studies that (1) link increased ambient air pollution (AP) with an increase in lung cancer incidence rates and (2) investigate whether residing in green spaces could be protective against cancer. However, it is completely unclear whether other forms of cancer are also affected by AP and if residential green spaces could lower cancer incidence rates in general. Therefore, the objective was to estimate whether AP and green space are associated with several cancer types. Methods The analysis was based on routine health care data from around 1.9 million people from Saxony who were free of cancer in 2008 and 2009. Incident cancer cases (2010–2014) of mouth and throat, skin (non-melanoma skin cancer - NMSC), prostate, breast, and colorectum were defined as: (1) one inpatient diagnosis, or (2) two outpatient diagnoses in two different quarters within one year and a specific treatment or death within two quarters after the diagnosis. Exposures, derived from freely available 3rd party data, included particulate matter with aerodynamic diameter of less than 10 μm (PM10) and nitrogen dioxide (N02) as well as green space (Normalized Difference Vegetation Index - NDVI). Associations between air pollutants, green space, and cancer incidence were assessed by multilevel Poisson models. Age, sex, physician contacts, short- and long-term unemployment, population density, and having an alcohol-related disorder were considered as potential confounders. Results Three thousand one hundred seven people developed mouth and throat cancer, 33,178 NMSC, 9611 prostate cancer, 9577 breast cancer, and 11,975 colorectal cancer during the follow-up period (2010–2014). An increase in PM10 of 10 μg/m3 was associated with a 53% increase in relative risk (RR) of mouth and throat cancer and a 52% increase in RR of NMSC. Prostate and breast cancer were modestly associated with PM10 with an increase in RR of 23 and 19%, respectively. The associations with N02 were in the same direction as PM10 but the effect estimates were much lower (7–24%). A 10% increase in NDVI was most protective of mouth and throat cancer (− 11% RR) and of NMSC (− 16% RR). Colorectal cancer was not affected by any of the exposures. Conclusions In addition to the studies carried out so far, this study was able to provide evidence that higher ambient AP levels increase the risk of mouth and throat cancer as well as of NMSC and that a higher residential green space level might have a protective effect for NMSC in areas with low to moderate UV intensity. Nevertheless, we cannot rule out residual confounding by socioeconomic or smoking status.
145

Climate deteriorations and Neanderthal demise in interior Iberia

Wolf, Daniel, Kolb, Thomas, Alcaraz-Castaño, Manuel, Heinrich, Susann, Baumgart, Philipp, Calvo, Ruben, Sánchez, Jésus, Ryborz, Karolin, Schäfer, Imke, Bliedtner, Marcek, Zech, Roland, Zöller, Ludwig, Faust, Dominik 15 June 2018 (has links)
Time and circumstances for the disappearance of Neanderthals and its relationship with the advent of Modern Humans are not yet sufficiently resolved, especially in case of the Iberian Peninsula. Reconstructing palaeoenvironmental conditions during the last glacial period is crucial to clarifying whether climate deteriorations or competition and contacts with Modern Humans played the pivotal role in driving Neanderthals to extinction. A high-resolution loess record from the Upper Tagus Basin in central Spain demonstrates that the Neanderthal abandonment of inner Iberian territories 42 kyr ago coincided with the evolvement of hostile environmental conditions, while archaeological evidence testifies that this desertion took place regardless of modern humans’ activities. According to stratigraphic findings and stable isotope analyses, this period corresponded to the driest environmental conditions of the last glacial apart from an even drier period linked to Heinrich Stadial 3. Our results show that during Marine Isotope Stages (MIS) 4 and 2 climate deteriorations in interior Iberia temporally coincided with northern hemisphere cold periods (Heinrich stadials). Solely during the middle MIS 3, in a period surrounding 42 kyr ago, this relation seems not straightforward, which may demonstrate the complexity of terrestrial climate conditions during glacial periods.
146

A cross-sectional investigation of the health needs of asylum seekers in a refugee clinic in Germany

Goodman, Laura F., Jensen, Guy W., Galante, Joseph M., Farmer, Diana L., Taché, Stephanie 15 June 2018 (has links)
Background Over one million asylum seekers were registered in Germany in 2016, most from Syria and Afghanistan. The Refugee Convention guarantees access to healthcare, however delivery mechanisms remain heterogeneous. There is an urgent need for more data describing the health conditions of asylum seekers to guide best practices for healthcare delivery. In this study, we describe the state of health of asylum seekers presenting to a multi-specialty primary care refugee clinic. Methods Demographic and medical diagnosis data were extracted from the electronic medical records of patients seen at the ambulatory refugee clinic in Dresden, Germany between 15 September 2015 and 31 December 2016. Data were de-identified and analyzed using Stata version 14.0. Results Two-thousand-seven-hundred and fifty-three individual patients were seen in the clinic. Of these, 2232 (81.1%) were insured by the state indicating arrival within the last 3 months. The median age was 25, interquartile range 16–34. Only 786 (28.6%) were female, while 1967 (71.5%) were male. The most frequent diagnoses were respiratory (17.4%), followed by miscellaneous symptoms and otherwise not classified ailments (R series, 14.1%), infection (10.8%), musculoskeletal or connective tissue (9.3%), gastrointestinal (6.8%), injury (5.9%), and mental or behavioral (5.1%) categories. Conclusions This study illustrates the diverse medical conditions that affect the asylum seeker population. Asylum seekers in our study group did not have a high burden of communicable diseases, however several warranted additional screening and treatment, including for tuberculosis and scabies. Respiratory illnesses were more common amongst newly arrived refugees. Trauma-related mental health disorders comprised half of mental health diagnoses.
147

Mitochondrial ROS direct the differentiation of murine pluripotent P19 cells

Pashkovskaia, Natalia, Gey, Uta, Rödel, Gerhard 13 December 2018 (has links)
ROS are frequently associated with deleterious effects caused by oxidative stress. Despite the harmful effects of non-specific oxidation, ROS also function as signal transduction molecules that regulate various biological processes, including stem cell proliferation and differentiation. Here we show that mitochondrial ROS level determines cell fate during differentiation of the pluripotent stem cell line P19. As stem cells in general, P19 cells are characterized by a low respiration activity, accompanied by a low level of ROS formation. Nevertheless, we found that P19 cells contain fully assembled mitochondrial electron transport chain supercomplexes (respirasomes), suggesting that low respiration activity may serve as a protective mechanism against ROS. Upon elevated mitochondrial ROS formation, the proliferative potential of P19 cells is decreased due to longer S phase of the cell cycle. Our data show that besides being harmful, mitochondrial ROS production regulates the differentiation potential of P19 cells: elevated mitochondrial ROS level favours trophoblast differentiation, whereas preventing neuron differentiation. Therefore, our results suggest that mitochondrial ROS level serves as an important factor that directs differentiation towards certain cell types while preventing others.
148

Portable Analyzer for On-Site Determination of Dissolved Organic Carbon — Development and Field Testing

Glorian, Heinrich, Schmalz, Viktor, Lochyński, Pawel, Fremdling, Paul, Börnick, Hilmar, Worch, Eckhard, Dittmar, Thomas 25 February 2019 (has links)
Dissolved organic carbon (DOC) is a sum parameter that is frequently used in water analytics. Highly resolved and accurate DOC data are necessary, for instance, for water quality monitoring and for the evaluation of the efficiency of treatment processes. The conventional DOC determination methods consist of on-site sampling and subsequent analysis in a stationary device in a laboratory. However, especially in regions where no or only poorly equipped laboratories are available, this method bears the risk of getting erroneous results. For this reason, the objective of the present study was to set up a reliable and portable DOC analyzer for on-site analysis. The presented DOC system is equipped with an electrolysis-based decomposition cell with boron-doped diamond electrodes (BDD) that oxidizes the organic compounds to carbon dioxide. Within this study, the influence of different electrode materials and the composition of the applied electrolytes on the DOC decomposition in an undivided electrolytic cell were systematically investigated. Furthermore, some technical aspects of the portable prototype are discussed. After a detailed validation, the prototype was used in an ongoing monitoring program in Northern India. The limit of detection is 0.1 mg L−1 C with a relative standard deviation of 2.3% in a linear range up to 1000 mg L C−1. The key features of the portable DOC analyzer are: No need for ultra-pure gases, catalysts or burning technology, an analyzing time per sample below 5 min, and a reliable on-site DOC determination.
149

Behavior change techniques for increasing physical activity in cancer survivors: a systematic review and meta-analysis of randomized controlled trials

Finne, Emily, Glausch, Melanie, Exner, Anne-Kathrin, Sauzet, Odile, Stölzel, Friederike, Seidel, Nadja 26 April 2019 (has links)
Purpose: The purpose of this systematic review and meta-analysis is to investigate how physical activity (PA) can be effectively promoted in cancer survivors. The effect of PA-promoting interventions in general, behavior change techniques (BCTs), and further variables as moderators in particular are evaluated. Methods: This study included randomized controlled trials of lifestyle interventions aiming at an increase in PA that can be carried out independently at home, published by December 2016, for adults diagnosed with cancer after completion of the main treatment. Primary outcomes were subjective and objective measures of PA prior to and immediately after the intervention. Meta-analysis and meta-regression were used to estimate effect sizes (ES) in terms of standardized mean differences, variation between ES in terms of heterogeneity indices (I2), and moderator effects in terms of regression coefficients. Results: This study included 30 studies containing 45 ES with an overall significant small positive effect size of 0.28 (95% confidence interval=0.18–0.37) on PA, and I2=54.29%. The BCTs Prompts, Reduce prompts, Graded tasks, Non-specific reward, and Social reward were significantly related to larger effects, while Information about health consequences and Information about emotional consequences, as well as Social comparison were related to smaller ES. The number of BCTs per intervention did not predict PA effects. Interventions based on the Theory of Planned Behavior were associated with smaller ES, and interventions with a home-based setting component were associated with larger ES. Neither the duration of the intervention nor the methodological quality explained differences in ES. Conclusion: Certain BCTs were associated with an increase of PA in cancer survivors. Interventions relying on BCTs congruent with (social) learning theory such as using prompts and rewards could be especially successful in this target group. However, large parts of between-study heterogeneity in ES remained unexplained. Further primary studies should directly compare specific BCTs and their combinations.
150

Triumfetta cordifolia: A Valuable (African) Source for Biocomposites

Grosser, Peter, Siegel, Carolin, Neinhuis, Christoph, Lautenschlaeger, Thea 26 April 2019 (has links)
The tradition of using naturally occurring plant fibers is still alive in Africa. In the Uíge province of northern Angola, bast fibers from Triumfetta cordifolia serve as the basis for everyday objects, such as baskets, mats, fishing nets, and traditional clothing. The fibers exhibit a Young’s modulus of 53.4 GPa and average tensile strength of 916.3 MPa, which are comparable to those of commercial kenaf fibers. These values indicate a high potential for use as a reinforcement in biocomposites. Based on this promising mechanical and physical profile of individual fibers, different biocomposites were produced with polylactide (PLA) as a matrix. The obtained composites were analyzed mechanically, physically, and visually. Unidirectionally arranged PLA/33% T. cordifolia composites with continuous fibers showed the highest Young’s modulus (10.79 GPa ± 1.52 GPa) and tensile strength (79.37 MPa ± 14.01 MPa). These composites were comparable to those of PLA/30% hemp composites (10.9 GPa and 82.9 MPa, respectively) and therefore have economic potential.

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