1,381 research outputs found

    Natural Family Planning and Catholic Hospitals: A National Survey

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    A recent survey conducted by the American Academy of Natural Family Planning (AANFP) found that over 55% of Catholic hospitals surveyed either provide or would like to provide some form of Natural Family Planning (NFP) services. In addition, over 60% of the respondents felt that NFP should be part of the mission of a Catholic hospital. This recent survey was conducted by the AANFP in order to determine the use of NFP in Catholic hospitals, (i.e., whether NFP is provided, types of NFP methods taught, teaching standardization and methodologies used, qualifications of NFP teachers, and the ethics of NFP services). This article is a report on that survey

    Semantic Tagging on Historical Maps

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    Tags assigned by users to shared content can be ambiguous. As a possible solution, we propose semantic tagging as a collaborative process in which a user selects and associates Web resources drawn from a knowledge context. We applied this general technique in the specific context of online historical maps and allowed users to annotate and tag them. To study the effects of semantic tagging on tag production, the types and categories of obtained tags, and user task load, we conducted an in-lab within-subject experiment with 24 participants who annotated and tagged two distinct maps. We found that the semantic tagging implementation does not affect these parameters, while providing tagging relationships to well-defined concept definitions. Compared to label-based tagging, our technique also gathers positive and negative tagging relationships. We believe that our findings carry implications for designers who want to adopt semantic tagging in other contexts and systems on the Web.Comment: 10 page

    Origin and reduction of wakefields in photonic crystal accelerator cavities

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    Photonic crystal (PhC) defect cavities that support an accelerating mode tend to trap unwanted higher-order modes (HOMs) corresponding to zero-group-velocity PhC lattice modes at the top of the bandgap. The effect is explained quite generally from photonic band and perturbation theoretical arguments. Transverse wakefields resulting from this effect are observed in a hybrid dielectric PhC accelerating cavity based on a triangular lattice of sapphire rods. These wakefields are, on average, an order of magnitude higher than those in the waveguide-damped Compact Linear Collider (CLIC) copper cavities. The avoidance of translational symmetry (and, thus, the bandgap concept) can dramatically improve HOM damping in PhC-based structures.Comment: 11 pages, 18 figures, 2 table

    Development of light-addressable potentiometric sensor systems and their applications in biotechnological environments

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    The simultaneous analysis of multiple analytes and spatially resolved measurements of concentration distributions with a single sensor chip are an important task in the field of (bio-)chemical sensing. Together with the miniaturisation, this is a promising step forward for applications and processes that profit from (bio-)chemical sensors. In combination with biological recognition elements, like enzymes or cells, these biosensors are becoming an interesting tool for e.g., biotechnological, medical and pharmaceutical applications. One promising sensor principle is the light-addressable potentiometric sensor (LAPS). A LAPS is a semiconductor-based potentiometric sensor that allows determining analyte concentrations of aqueous solutions in a spatially resolved manner. Therefore, it is using a focused light source to address the area of interest. The light that illuminates the local area of the LAPS chip generates a photocurrent that correlates with the local analyte concentration on the sensor surface. Based on the "state of the art", further developments of LAPS set-ups were carried out within this PhD thesis. Furthermore, by utilising enzymes and whole cells, the benefits of these LAPS set-ups for biotechnological, medical and pharmaceutical applications are demonstrated. During the present thesis, three different LAPS set-ups were developed: The first LAPS set-up makes use of a field-programmable gate array (FPGA) to drive a 4x4 light-emitting diode (LED) array that defines 16 measurement spots on the sensor-chip surface. With the help of the FPGA, the driving parameters, like light brightness, modulation amplitude and frequency can be selected individually and all LEDs can be driven concurrently. Thus, a simultaneous readout of all measurement spots is possible and chemical images of the whole sensor surface can be achieved within 200 ms. The FPGA-based LAPS set-up is used to observe the frequency behaviour of LAPS chips. In a second LAPS set-up, a commercially available organic-LED (OLED) display is used as light source. The OLED panel consists of 96x64 pixels with a pixel size of 200x200 µm and thus, an over 16 times higher lateral resolution compared to the IR-LED array. It was demonstrated that chemical images of the whole sensor surface can be obtained in 2.5 min. Since the lateral resolution of LAPS is not only specified by the light source, but also by the LAPS chip itself, the lateral resolution of the LAPS structures is characterised. Therefore, the third LAPS set-up has been developed, which utilises a single laser diode that can be moved by an XY-stage. By scanning a specially patterned LAPS chip, a lateral resolution of the LAPS structures in the range of the pixel size of the OLED display is demonstrated. Label-free imaging of biological phenomena is investigated with the FPGA-based LAPS. With the help of an enzymatic layer with the enzyme acetylcholine esterase (AChE) the detection of the neuronal transmitter acetylcholine (ACh) is demonstrated. The dynamic and static response as well as the long-term stability is characterised and compared with another semiconductor-based chemical imaging sensor based on charge-coupled devices (CCD) using the same enzymatic layer. The usage of the FPGA-based LAPS as whole-cell-based biosensor is studied with the model organism Escherichia coli. Here, the metabolic activity of the E. coli cells is investigated by determining the extracellular acidification. An immobilisation technique for embedding the microorganisms in polyacrylamide gel on the sensor surface has been developed. The immobilisation is realised in an on-chip differential arrangement by making use of the addressability of LAPS. This way, external influences such as sensor drift, temperature changes and external pH changes can be compensated. In a comparative study of the extracellular acidification rate between immobilised E. coli and E. coli that are in suspension, acidification rates in the same order were determined, demonstrating that the immobilisation does not have any influence on the metabolic activity. Further measurements with this cell-based LAPS system underline the sensitivity towards different nutrient concentrations, namely glucose. The ability to observe the extracellular acidification of microorganisms and the sensitively towards nutrient concentrations enables to detect high-order effects, like toxicity or pharmacological activity in complex analytes

    Counterpulsation cardiac assist device controller defection filter simulation and canine experiments

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    Electronic control systems for counterpulsation Cardiac Assist Devices (CADs) are an essential part of cardiac assistance. Synchronization of the counterpulsation CAD controller with the cardiac cycle is critical to the efficacy of the CAD. The robustness of counterpulsation CAD controllers varies with the ability of the CAD controller to properly trigger on aortic pressure (Pa) and electrocardiogram (ECG) signals for sinusoid rhythms, non-sinusoid rhythms and non-ideal signals resulting from surgical intervention. An analog-to-digital converter and digital-to-analog converter based CAD controller development platform was devised on a 33Mhz PC-AT. Counterpulsation Pa systolic rise and dicrotic notch detectors were demonstrated with a 15cc pediatric Intraaortic Balloon (IAB) and 50cc Extraaortic Counterpulsation Device (EACD) CADs using mongrel canine experimental models in which biological variation due to changing heart rate and arrhythmia as well as surgical interference due to mechanical ventilation, electrocautery, signal attenuation and random noise was present. The robust Pa triggering algorithm was based on a derivative comparator riding clipper algorithm for the Pa-based controller. In order to empirically determine the robustness of the Pa triggering algorithms, a simulation platform, Pa trace model, and Pa trace artifact and physiological variation models were devised. Each set of simulation experiments utilized a different Pa trace artifact or physiological variation model to determine the capability of the Pa trigger algorithm to withstand the effects of the Pa detection impediments while maintaining 100% accuracy of the dicrotic notch detection. Multiple simulation experiments were conducted in which the same nominally adjusted interference was increased to benchmark the immunity threshold of the dicrotic notch detector. Biological variation and deviations in Pa artifacts due to clinical conditions experienced in cardiothoracic surgery were investigated. Pa triggering was unhindered by biological variation of a Pa trace with a 3 mmHg dicrotic notch deflection along with a Pa trace with no dicrotic notch deflection present. Pa triggering was unhindered by heart rate variability ranging from 60 to 80 bpm due to respiration. Pa triggering was unhindered by clinical conditions including 40 mmHg changes in the Pa baseline modeling mechanical ventilation, aortic trace attenuation modeling variations in pressure transducer positioning and blood coagulation on the pressure catheter tip ranging from 100% to 200% of the Pa trace amplitude every four seconds, uniformly distributed noise with a mean of 0.5mmHg and standard deviation of 0.289mmHg and Gaussian distributed noise with a zero mean and standard deviation of 0.6nunHg. The results of the simulation experiments performed quantified the robustness of the Pa detection algorithm. Development of a fault tolerant counterpulsation CAD control system required the development of a robust ECG triggering algorithm to operate in tandem with the Pa triggering algorithm. An ECG detector was developed to provide robust control for a range of ECG traces due to biological variation and signal interference. The ECG R-wave detection algorithm is based on a modified version of the Washington University QRS-complex DD/1 algorithm (Detection and Delineation 1) which uses the associated AZTEC (Amplitude Zero Threshold Epic Coding) preprocessing algorithm and provides accurate ECG-based CAD control R-wave detection for 96.56% of the R-waves stored within the MIT/BIH ECG Arrhythmia database with a maximum detection delay of 8 milliseconds. Further IAB experiments performed with mongrel canine experimental models demonstrated that the systolic time interval to heart rate relationship existing in humans (essential to human patient CAD control inflation prediction) is not prevalent in canine mongrels particularly when treated with beta-blockers. In order to execute both Pa and ECG C software detection algorithms for a fault tolerant counterpulsation CAD controller, investigation into the communications throughput of a quad-transputer board was performed. Development of streamlined communication primitives led to a communication processor utilization of 8.3%, deemed efficient enough for fault tolerant multiprocessor CAD control implementation

    Zur Symptomatologie und Pathologie der Tumoren der Kleinhirnhemisphären

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    ZUR SYMPTOMATOLOGIE UND PATHOLOGIE DER TUMOREN DER KLEINHIRNHEMISPHÄREN Zur Symptomatologie und Pathologie der Tumoren der Kleinhirnhemisphären ([1]) Einband ( - ) Titelseite ([1]) Widmung ([3]) Kapitel ([5]) Danksagung (24) Literatur: ( - ) Lebenslauf. ( - ) Einband ( -
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