The tree of knot tunnels

We present a new theory which describes the collection of all tunnels of tunnel number 1 knots in the 3-sphere (up to orientation-preserving equivalence in the sense of Heegaard splittings) using the disk complex of the genus-2 handlebody and associated structures. It shows that each knot tunnel is obtained from the tunnel of the trivial knot by a uniquely determined sequence of simple cabling constructions. A cabling construction is determined by a single rational parameter, so there is a corresponding numerical parameterization of all tunnels by sequences of such parameters and some additional data. Up to superficial differences in definition, the final parameter of this sequence is the Scharlemann-Thompson invariant of the tunnel, and the other parameters are the Scharlemann-Thompson invariants of the intermediate tunnels produced by the constructions. We calculate the parameter sequences for tunnels of 2-bridge knots. The theory extends easily to links, and to allow equivalence of tunnels by homeomorphisms that may be orientation-reversing.Comment: This version has extensive minor rewriting for accuracy and clarity. The material on the depth invariant has been substantially expanded and moved into a new ArXiv preprint, The depth of a knot tunnel. Also moved there is the calculation of the slope sequences for the short tunnels of torus knot

Landscape and Literature

Panel: Landscape and Literatur

From the Inside Looking Out, Or, Notes from the Land-of-Eden-Corporation

Panel: America Abroa

Andre Goeritz MFA Thesis Statement

I strive to make objects of no complicity--arranging smaller parts to create larger forms, or allowing the combination of parts to allude to narratives without linearity, foreshadowing, point of entry, point of attack, conflict, context, or catharsis; a state of sustained stillness until equilibrium is no longer a desired result, at which point the parts of the whole can be dismantled, reconfigured, made anew. I think about words, rhythm, inflection, resonance or timbre, vocal dissonance, dismembered disjointed utterances, and repetition--somatic impulses guided by intent. Intention translates into action--an act of will, a willful act, an act of willful intent--a marker of making, solidifying and codifying an abstracted linguistic turn--turned into intentioned form--neither act nor intent as inception of the work, yet both accountable for the resultant iteration. Entropic forces encroach on seemingly stable forms that repeat, upward and outward--the expansion of volume extended in time playing on the senses in a collapsed field. Please see Download button in top right corner for the full statement

Ein übergreifendes Forschungsinformationssystem für die Leibniz-Gemeinschaft

Für die Arbeit von Forschungseinrichtungen und -organisationen sind Forschungsinformationen von großer Bedeutung. Neben der Berichterstattung an Fördermittelgeber finden sie unter anderem Einsatz bei strategischen Entscheidungen und in der Öffentlichkeitsarbeit. Die vorliegende Masterarbeit beschäftigt sich mit dem Umgang mit Forschungsinformationen in der Leibniz- Gemeinschaft, insbesondere institutsübergreifend im Sinne der Idee eines auf Gemeinschaftsebene funktionierenden Leibniz-Forschungsinformationssystems (Leibniz-CRIS). Dabei werden im Rahmen qualitativer Interviews und einer quantitativen Umfrage bestehende Probleme und Herausforderungen im Forschungsinformationsmanagement sowie Erwartungen und Anforderungen an ein Leibniz-CRIS erhoben und ermittelt, welchen Einfluss die Weiterentwicklung des in der Leibniz-Geschäftsstelle verwendeten Informationssystems zur Datenerfassung und Auswertung (IDA) hierauf hat. Während die Ergebnisse auf durchaus unterschiedliche Ansichten und Bedürfnisse in den einzelnen Leibniz- Einrichtungen hindeuten, zeigen sie doch gewisse Tendenzen, wie den Wunsch nach mehr Standardisierung etwa unter Verwendung des Kerndatensatzes Forschung (KDSF), einen hohen Kommunikationsbedarf im Zusammenhang mit der Einrichtung eines Leibniz-CRIS und den Nutzen von Schnittstellen in institutsübergreifenden Systemen wie IDA. Die aus den Erhebungen gewonnenen Erkenntnisse führen zu Empfehlungen zum Prozess der Etablierung eines Leibniz- CRIS und zur weiteren Entwicklung IDAs.Research information is of great importance for the work of research institutions and organizations. In addition to reporting processes, research information is also used in other contexts, such as strategic decision-making and public relations. This Master's thesis deals with the management of research information in the Leibniz Association particularly across institutes, following the idea of a Leibniz-Current Research Information System (Leibniz- CRIS) functioning at the level of the Leibniz Association as a whole. By conducting qualitative interviews and a quantitative survey, existing problems and challenges in research information management as well as expectations of and requirements for a Leibniz-CRIS are identified and the influence of the further development of the "Informationssystem zur Datenerfassung und Auswertung" (IDA) used at Leibniz Headquarters in this context is determined. While the results indicate quite different views and requirements within the individual Leibniz institutes, they show certain tendencies such as a desire for more standardization, for example by use of the "Kerndatensatz Forschung" (KDSF), a high need for communication regarding the establishment of a Leibniz-CRIS, and the usefulness of APIs in cross-institutional systems such as IDA. The research findings lead to recommendations on the process of establishing a Leibniz-CRIS and on the further development of IDA

The Long Gestation of the Small Naked Mole-Rat (Heterocephalus glaber RÜPPELL, 1842) Studied with Ultrasound Biomicroscopy and 3D-Ultrasonography

The naked mole-rat (Heterocephalus glaber) is one of the two known mammalian species that live in a eusocial population structure. Here we investigate the exceptionally long gestation period of 70 days observed in the mole-rat queen. The course of seven successful pregnancies in two individuals was recorded in a colony of captive naked mole-rats using ultrasound biomicroscopy (UBM) and 3D-ultrasonography. We establish a catalogue of basic reference ultrasound data for this species by describing the ultrasonographic appearance of reproductive organs, calculating growth curves to predict gestational age and defining ultrasonographic milestones to characterize pregnancy stages. Mean litter size was 10.9±2.7, of which 7.2±1.5 survived the weaning period. Mean interbirth interval was 128.8±63.0 days. The reproductive success in our colony did not differ from previously published data. In the queen the active corpora lutea had an anechoic, fluid filled centre. Using UBM, pregnancy could be detected 53 days before parturition. The period of embryonic development is assumed to last until 30 days before parturition. Embryonic resorptions were detected frequently in the queen, indicating that this might be an ordinary event in this species. We discuss the extraordinary long gestation period of this small rodent and postulate that the long gestation is beneficial to both the eusocial structure and longevity. An increased litter size, twice as large as for other rodents of similar size, seemingly compensates for the doubling of pregnancy length. We demonstrate that the lifetime reproductive effort of a naked mole-rat queen is equivalent to the mass of offspring that would be produced if all of the females of a colony would be reproducing

Tiergesundheitspläne und Tiergesundheitsindikatoren aus Sicht ökologisch wirtschaftender MilchviehhalterInnen - erste Ergebnisse einer Pilotstudie in Deutschland

In a pilot study on the implementation of herd health plans in organic dairy farms in Germany, 43 organic milk producers were interviewed about their opinion about this management tool to improve animal health. Preliminary results show that the farmers have nearly the same target values for indicators of animal health like experts and advisors. By contrast, on-farm data collection reveals discrepancies between these goals and the actual situation. Thus a systematic procedure by using herd health plans and a straightforward implementation of measures could improve animal health. However, it is important for the farmers to adjust the herd health plan and the advised measures individually

Gesundheitserhebung bei Legehennen zur Verbesserung der Tiergesundheit durch Implementierung von Tiergesundheitsplänen

This study was implemented to improve animal health of laying hens on organic farms. 20 farms were selected and animal health was evaluated. The farmers were inter-viewed about the housing system and management practices. Health and behavioural problems of the herd, as well as the incidence of endo- and ectoparasites were as-sessed. Housing facilities were evaluated and potential causes of health problems noted. Most of the farms have problems with damaged plumage and with the red mite (Dermanyssus gallinae). In most cases farmers know about these problems, but the reasons are difficult to find. This was the next step within the project (results not shown). Potential causes of problems were identified and farm specific animal health plans implemented to improve the animal health status on the farms

Akzeptanz von Tiergesundheitsplänen bei Landwirten – Ergebnisse einer Befragung bei 60 Betrieben

In organic farming the ambitious claims in enhancing and keeping animal health are often not realised. The implementation of animal health plans should clear this deficit effectively. Experiences with British and Danish herd health plans showed that the acceptance of plans is an essential part for its successful transfer into practice. But anyhow, this aspect has not been regarded sufficiently. To avoid similar mistakes like done in former institution tests a social study is integrated into German projects that deal with the implementation of animal health plans in poultry, dairy, and pig hus-bandry. To get more information about the acceptance, the study requires farmers’ attitudes to herd health plans, the motivation to animal health and financial and work capabilities as well

Ertragsleistung und Rutingehalte verschiedener Buchweizensorten unter ökologischen Anbaubedingungen

Buckwheat is an ancient traditional food and medicinal plant. In this study we investigated grain yield and rutin content of common (Bamby, Lileja, Hruszowska) and tataric (Lifago) buckwheat varieties under organic farming conditions at different N levels. Grain yield and rutin content were not significantly affected by the factors ‘year’ and ‘N-supply’. However, strong effects of the factor ‘variety’ could be determined. The tataric buckwheat Lifago showed highest grain and rutin yields compared to the common buckwheat varieties. Due to the rutin related bitter taste Lifago buckwheat is rather useful for medical application than for basic food. Converting rutin into less bitter active substance quercetin during processing as well as cross-breeding of common buckwheat x wild type buckwheat might be alternatives for basic food application. Since we found no effect of additional N-supply, buckwheat is well suited for low input farming systems like organic farming