Add-A-Tag: Learning Adaptive User Profiles from Bookmark Collections

In this paper we construct adaptive user profiles from tagging data. We present and evaluate an algorithm for creating such profiles, characterizing its behavior through statistical analysis

School-Based Service Delivery Models and Interventions for Handwriting

This project was part of a research initiative in collaboration with Wendi Trummert, DrOT, OTR/L, a practicing school-based occupational therapist in the Puyallup School District. The purpose of our project was to compare the effectiveness of certain service delivery models and intervention approaches to improve handwriting outcomes for school-aged children. Our search of the literature yielded a total of 20 applicable research studies, which utilized a wide variety of models and approaches. There was limited research specifically comparing service delivery and/or specific components of handwriting interventions. Our findings indicated that there are a variety of effective service delivery models and approaches to handwriting interventions. Furthermore, direct practice was a consistent component of programs producing handwriting improvements. A recommendation for future research is to directly compare service delivery models and intervention approaches to handwriting. This would allow practitioners to identify which specific aspects of service delivery could best support handwriting for students. Our knowledge translation products were specifically designed for our collaborating practitioner to present to her colleagues within the Puyallup School District. These products included a prepared in-service presentation detailing our research and findings, handouts regarding service delivery and approaches, and an annotated bibliography including relevant research articles to inform practitioners. Post-product responses and feedback were overall positive from our collaborator, although we were not able to receive feedback from colleagues who participated in the presentation due to time constraints

PER-formance

Diese Arbeit hat das Ziel ein personengebundenes Programm zur Primärprävention von Essstörungen bei Leistungssportlerinnen zu entwickeln, zu implementieren und nach wissenschaftlichen Kriterien zu evaluieren, da für Leistungssportlerinnen keinerlei wissenschaftlich evaluierte spezifische Präventionsprogramme vorliegen (Thompson & Sherman, 2010). Als Grundlage wird das Modell von Slade (1982, zit. n. Meermann & Borgart, 2006) zur funktionalen Analyse der Anorexia Nervosa mit sportspezifischen Risikofaktoren und sportspezifischen Essverhaltensstörungen ergänzt. Mit Hilfe des MoVo-Konzepts (Fuchs, 2006, 2007) werden Verhaltensweisen als Zielvariablen bestimmt, die ein ausreichendes (gesundes) Ernährungsverhalten sicherstellen sollen. Ziel des Programms PER-formance- Prävention von Essstörungen in Risikosportarten – ist es ein positives Körperbild zu stärken und/ oder zu entwickeln sowie Wissen über Essstörungen im Leistungssport, körperliche Veränderungen in der Pubertät sowie der Menstruation zu erweitern und den Umgang mit kränkenden Kommentaren bezogen auf Aussehen und/oder Gewicht zu verbessern. Das Programm PER-formance richtet sich an Leistungssportlerinnen im Alter von 12-16 Jahren aus Sportarten, die ein erhöhtes Risiko für die Entwicklung von Essstörungen haben. An der zweiphasigen Untersuchung nehmen sechs Gruppen mit insgesamt 90 Mädchen teil. Die Machbarkeitsanalyse zeigt, dass das Programm sehr gut angenommen wird und spricht für eine gelungene Implementierung. Die Wirksamkeitsanalyse erfolgt anhand eines quasi-experimentellen Designs mit drei Messzeitpunkten. Deutlich positive Effekte werden in der Wissensvermittlung erzielt. In den Veränderungen der Verhaltensweisen zeigen sich geringe Effekte, die mit internationalen Studien zur Essstörungsprävention vergleichbar sind. Die Mädchen beschreiben weniger gestörte Essverhaltensweisen sowie reduzierte perfektionistische Tendenzen und Sorge um Fehler und einen gesteigerten Einsatz emotionsregulierender Stressverarbeitungsstile. Veränderungen im Körperbild konnten nicht nachgewiesen werden.This thesis aims to develop, implement and evaluate a personal program to prevent eating disorders (ED) in high level athletes as there are no evaluated programs of that kind (Thompson & Sherman, 2010). In a first step, the functional model of Anorexia Nervosa (Slade, 1982, cited by Meermann & Borgart, 2006) is complemented with sport-specific risk factors for eating disorders and sport-specific disordered eating. Outcome variables are specified based on the concept of MoVo (Fuchs, 2006, 2007) that should ensure sufficient (healthy) eating. The program PER-formance – prevention of eating disorders in high level sports – aims to strengthen and/ or develop a positive body image, to increase knowledge about eating disorders in high level sports and about body changes during puberty and menstruation. In addition, it intends to support athletes in dealing with harmful comments related to appearance and/ or weight. PER-formance is developed for 12-16 year old female high-level athletes in sports with an increased risk for developing eating disorders. Six groups with a total of 90 girls take part in the two-phase study. The results of the feasibility study demonstrate a successful implementation and good acceptance of the program. The evaluation study follows a quasi-experimental design with three measuring points. Partici-pants’ knowledge about eating disorders, puberty and menstruation increases significantly. As shown in comparable international studies dealing with the prevention of eating disorders, smaller effects are in relation to behavioral changes. The athletes report less disordered eating and lower tendencies of perfectionism and care for mistakes as well more frequent adoption of of emotion-regulating coping strategies. No changes in body image are found

Isobar separation with post-stripping for the measurement of cosmogenic Be-10 at VERA

Beryllium-10 (t1/2 = 1.5 Ma) ist ein wichtiges kosmogenes Radionuklid für die Beschleuniger-Massenspektrometrie (AMS). Die größte Herausforderung bei der Messung von Be-10 ist der Hintergrund durch das stabile Isobar Bor-10. Die beiden Isobare können nicht effizient anhand ihres kleinen Massenunterschieds (∆M/M = 6·10⁻⁵) getrennt werden. Die Trennung beruht auf dem unterschiedlichen Energieverlust des Ionenstrahls in Materie, aufgrund der verschiedenen Kernladungszahl von Be-10 und B-10. Früher wurde bei VERA, dem Vienna Environmental Research Accelerator, ein Absorber vor einem Teilchendetektor verwendet, um den Hintergrund durch Bor zu unterdrücken. Ein alternativer Ansatz zur Trennung von Be-10 und B-10 ist Poststripping: nach der Beschleunigung im Tandem-Beschleuniger auf ∼8MeV passiert der Ionenstrahl eine ∼500nm dicke Folie. Die Isobare haben danach unterschiedliche Restenergien und können durch einen energieempfindlichen Analysator getrennt werden. Ich führte Poststripping für die Messung von Be-10 bei VERA ein. Dabei verwendete ich Siliziumnitrid-Folien für das Strippen und einen Switcher-Magneten als Analysator. Außerdem nützte ich eine neue ∆E-E-Ionisationskammer mit einer unterteilten Anode. Bevor ich mich für den Switcher-Magneten entschied, zog ich auch andere Messaufbauten in Erwägung. Computersimulationen halfen mir einen guten Messaufbau zu planen. Schließlich wurde Poststripping bei VERA zur Messung von Be-10 verwendet. Poststripping hat einen niedrigeren Hintergrund (Be-10/Be-9 ≈ 2·10⁻¹⁵) als die Absorbermethode bei vergleichbarer Effizienz.Beryllium-10 (t1/2 = 1.5 Ma) is an important cosmogenic radionuclide in accelerator mass spectrometry (AMS). The biggest challenge in Be-10 measurement is the background of the stable abundant isobar Boron-10. The two isobars cannot be separated efficiently by their small mass difference (∆M/M = 6 ·10−5 ). Their separation is based on the difference in energy loss of the ion beam in matter due to the different atomic number of Be-10 and B-10 respectively. In the past at VERA, the Vienna Environmental Research Accelerator, an absorber in front of a particle detector was used to suppress the boron background. An alternative approach to separate Be-10 and B-10 is post-stripping: after acceleration in the tandem accelerator to ∼8MeV, the ion beam passes through a ∼500nm thick foil, which results in different residual energies of the isobars. The ions can be separated by an energy-sensitive analyzer. I have implemented post-stripping for the measurement of Be-10 at VERA. In my measurement setup I have used silicon nitride foils for the stripping and a switching magnet as analyzer. Further, I took advantage of a new ∆E-E ionization chamber with a segmented anode. Before I decided to use the switching magnet, I had considered alternative setups. Computer simulations of the ion optics helped finding a good setup. Finally, post-stripping is used at VERA for the measurement of Be-10. It has a lower measurement background (Be-10/Be-9 ∼ 2·10⁻¹⁵) than the method used before and the efficiencies of both methods are comparable

Mechanisms for acoustic emissions generation during granular shearing

Shear deformation of granular media leads to continual restructuring of particle contact network and mechanical interactions. These changes to the mechanical state include jamming of grains, collisions, and frictional slip of particles—all of which present abrupt perturbations of internal forces and release of strain energy. Such energy release events typically result in the generation of elastic waves in the kHz frequency range, termed acoustic emissions (AE). The close association between grain-scale mechanics and AE generation motivated the use of AE as surrogate observations to assess the mechanical state of complex materials and granular flows. The study characterizes AE generation mechanisms stemming from grain-scale mechanical interactions. Basic mechanisms are considered, including frictional slip between particles, and mechanical excitation of particle configurations during force network restructuring events. The intrinsic frequencies and energy content of generated AEs bear the signature of source mechanisms and of structural features of the grain network. Acoustic measurements in simple shear experiments of glass beads reveal distinct characteristics of AE associated with different source mechanisms. These findings offer new capabilities for non-invasive interrogation of micromechancial interactions and linkage to a stochastic model of shear zone mechanics. Certain statistical features of restructuring events and associated energy release during shearing were predicted with a conceptual fiber-bundle model (FBM). In the FBM the collective behavior of a large number of basic mechanical elements (representing e.g. grain contacts), termed fibers, reproduces the reaction of disordered materials to progressive loading. The failure of fibers at an individual threshold force corresponds to slipping of a particle contact or a single rearrangement event of the granular network. The energy release from model fiber breakage is the equivalent to elastic energy from abrupt grain rearrangement events and provides an estimate of the energy available for elastic wave generation. The coupled FBM-AE model was in reasonable agreement with direct shear experiments that were performed on large granular assemblies. The results underline the potential of using AE as a diagnostic tool to study micro-mechanical interactions, shear failure and mobilization in granular material

Evaluation of the food grade expression systems NICE and pSIP for the production of 2,5-diketo-D-gluconic acid reductase from Corynebacterium glutamicum

2,5-diketo-D-gluconic acid reductase (2,5-DKG reductase) catalyses the reduction of 2,5-diketo-D-gluconic acid (2,5-DKG) to 2-keto-L-gulonic acid (2-KLG), a direct precursor (lactone) of L-ascorbic acid (vitamin C). This reaction is an essential step in the biocatalytic production of the food supplement vitamin C from D-glucose or D-gluconic acid. As 2,5-DKG reductase is usually produced recombinantly, it is of interest to establish an efficient process for 2,5-DKG reductase production that also satisfies food safety requirements. In the present study, three recently described food grade variants of the Lactobacillales based expression systems pSIP (Lactobacillus plantarum) and NICE (Lactococcus lactis) were evaluated with regard to their effictiveness to produce 2,5-DKG reductase from Corynebacterium glutamicum. Our results indicate that both systems are suitable for 2,5-DKG reductase expression. Maximum production yields were obtained with Lb. plantarum/pSIP609 by pH control at 6.5. With 262 U per litre of broth, this represents the highest heterologous expression level so far reported for 2,5-DKG reductase from C. glutamicum. Accordingly, Lb. plantarum/pSIP609 might be an interesting alternative to Escherichia coli expression systems for industrial 2,5-DKG reductase production