2,485 research outputs found

    Connected Lie Groupoids are Internally Connected and Integral Complete in Synthetic Differential Geometry

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    We extend some fundamental definitions and constructions in the established generalisation of Lie theory involving Lie groupoids by reformulating them in terms of groupoids internal to a well-adapted model of synthetic differential geometry. In particular we define internal counterparts of the definitions of source path and source simply connected groupoid and the integration of AA-paths. The main results of this paper show that if a classical Hausdorff Lie groupoid satisfies one of the classical connectedness conditions it also satisfies its internal counterpart.Comment: Statement of Theorem 4.7 and notation in Section 4.3 correcte

    Early rebellion and its links to later success and conquest: Why was it that some Norman rulers profited from rebellions early in their reigns, whilst others did not?

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    The subject of this dissertation is the Normans. Its objective is to analyse the development of their civilisation, and to give reasons for their numerous accomplishments, both in Northern Europe and in the Mediterranean. Yet, unlike the many scholars who have studied the Normans before, the main focus here will be on rebellion, and in particular those rebellions which followed the succession of each Norman ruler (either a king or a duke/count), as it will be argued that when dealt with correctly these revolts did not hinder, but instead created the seeds of power and progress; since they gave the new ruler an opportunity to establish a lasting precedent early on, that insolence to their authority would not be tolerated; which if accomplished, then led to harmony (internal peace), development and conquest for the rest of the ruler’s reign

    GPR investigations of the sedimentary architecture of jökulhlaup eskers : Skeidarájökull, Iceland and Bering glacier, Alaska

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    Abstract Eskers are ridges of stratified glaciofluvial material deposited in englacial, subglacial or supraglacial channels and ice-walled canyons. Eskers have been used to infer the dynamics and palaeo-hydrology of large ice sheets, despite observations of palaeo-esker sedimentary architecture lacking rigorous constraints on depositional timescale. This research aims to identify the hydrological, glaciological and sedimentary controls on the sedimentary architecture of single event outburst flood (jokulhlaup) eskers at SkeiOarârjOkull and Bering Glacier. These eskers formed during monitored outbursts, providing time constraints on the depositional events, thereby making the eskers ideal analogues for palaeo-eskers. GPR data was collected using a pulseEKKO Pro 1100 system at SkeiOarârjOkull and Bering Glacier during field seasons in 2006 and 2007. At SkeiOarãrjOkull grids of 100 MHz GPR lines were collected on the glacier surface and 200 MHz GPR grids were collected on all workable sections of an esker and ice-walled canyon fill generated by a jokulhlaup in November 1996. At Bering Glacier 200 MHz GPR grids were collected on workable sections of an ice-walled canyon fill and esker generated during outbursts in July-August and October 1994, respectively. Examination of the GPR data has allowed development of site-specific models for esker and ice-walled canyon fill deposition, providing the first detailed insight into the sedimentary architecture of single event jokulhlaup eskers. These models show that single high-magnitude jOkulhlaups can generate eskers with complexities previously unexpected for single events. The englacial position of an esker is controlled by the presence of structural weaknesses within the ice and the jokulhlaup release mechanism. Esker sedimentary architecture, on the other hand, is controlled by a complex interaction between hydrological, glaciological and sedimentary factors. The most fundamental control on jokulhlaup esker sedimentary architecture is conduit geometry, which determines the type of macroform from which the esker is composed. Thus, eskers deposited during jOkulhlaups should be made up of both wide ridges as composite macroforms in areas of conduit expansion and narrow ridges composed of upper-stage plane beds in constricted conduits. The smaller scale sedimentary features, which include antidunes and boulder clusters, as well as the frequency of erosional structures, are controlled by interactions between the flow conditions and sediment supply. The eskers generated during the 1996 SkeiOarãrhlaup and 1994 Bering Glacier outburst flood demonstrate sedimentary architectures that are similar to those identified in many palaeo-eskers described from previous studies. The research suggests that jOkulhlaups may have had a greater role in palaeo-esker sedimentary architecture than previously hypothesised

    Understanding the Skills Necessary for Advanced Practice Nurses in Oncology to Deliver Bad News to Patients with Cancer: The Results of a Delphi Analysis

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    Overcoming the dichotomy of providing bad news in a compassionate, empathetic manner that strengthens dialogue and enhances a caring environment is the ultimate challenge advanced practice nurses (APN) face in oncology. This study aims to understand the skills necessary for APNs in oncology to deliver bad news to patients with cancer. Using a Delphi analysis, an established method of developing a consensus, a novel, patient-centered survey tool has been developed designed to extract as much information as possible about the present issue from an expert panel. Oncology APNs were recruited via Facebook. The survey tool was administered using a web-based survey tool. Content analysis was applied to the stories and responses to open-ended questions that panelists submitted. Results were collected and then presented back to the panel for ranking. Twelve expert panelists reached a consensus on a practice-based method focused on teaching empathy and self-awareness. The results of this pilot project serve as the foundation for future research and for the development of a curriculum to educate new APNs or those new to the field of oncology

    The Movement: A Performance Venue

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    The aim for the thesis project is to design a concert venue for the City of Saint Albans, Vermont. The venue will serve as an entertainment hotspot, an educational tool, a set of rehearsal spaces, and performance halls with recording capabilities. The goal is to create a welcoming entertainment and educational environment, open to use by all, to show that music is more than entertainment, but also a hobby, an educational medium, a skill-set, and a tool. The driving theme behind the project is the concept of movement. Its first representation is in music. Sound itself is movement; it is pressure; it is the air moving around you, translated to the audible spectrum by your ears and brain. It is impossible to perform music without moving in some way. Second, water will be moving through the building (as in all buildings), but in this special case through an in-pipe microhydropower system. Lastly, the idea of a landmark, contemporary concert hall in Saint Albans constitutes progress and forward movement in the City’s development

    Stacked generative adversarial networks for learning additional features of image segmentation maps

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    It has been shown that image segmentation models can be improved with an adversarial loss. Additionally, previous analysis of adversarial examples in image classification has shown that image datasets contain features that are not easily recognized by humans. This work investigates the effect of using a second adversarial loss to further improve image segmentation. The proposed model uses two generative adversarial networks stacked together, where the first generator takes an image as input and generates a segmentation map. The second generator then takes this predicted segmentation map as input and predicts the errors relative to the ground truth segmentation map. If these errors contained additional features that are not easily recognized by humans, they could possibly be learned by a discriminator. The proposed model did not consistently show significant improvement over a single generative adversarial model, casting doubt about the existence of such features

    Blueprinting Self-Assembled Soft Matter: An `Easy' Approach to Advanced Material Synthesis in Drug Delivery and Wound Healing

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    From Jello to mayonnaise to silly putty to biological cells, our world is replete with "soft matter" - materials that behave as soft, deformable solids or highly viscoelastic liquids. Living systems, in particular, can be thought of as extremely sophisticated `soft' machines, with each cellular unit representing a touchstone for the functional potential of soft materials built via self-assembly. Drawing inspiration from biology, we blueprint soft biomaterial designs which rely upon self-assembly to achieve enhanced functionality. As opposed to complex synthesis schemes often used to develop improved biomaterials, we take an `easy' approach by allowing relatively simple molecules orchestrate themselves into advanced machines. In this dissertation, we describe four separate "soft" systems, all constructed by self-assembly of amphiphilic molecules under designed and/or triggered conditions in aqueous media. These systems revolve around a common theme: the structural tandem of (1) vesicles and (2) biopolymers, and the resulting interactions between the two. Our blueprints show promise in several important biomedical applications including controlled drug release, tissue engineering, and wound care. In the first part of this study, we blueprint a biopolymer gel that entraps pH-sensitive vesicles. The vesicles are formed by the self-assembly of a single-tailed fatty acid surfactant. We show that the gel has pH-responsive properties imparted upon it via the embedded vesicle nanostructures. Specifically, when the gel is brought in contact with a high pH buffer, the diffusion of buffer into the gel disrupts the vesicles and transforms them into micelles. Accordingly, a vesicle-micelle front moves through the gel, and this can be visually seen by a difference in color. The disruption of vesicles means that their encapsulated solutes are released into the bulk gel, and in turn these solutes can rapidly diffuse out of the gel. Thus, we can use pH to tune the release rate of model drug molecules from these vesicle-loaded gels into the external solution. In the second part, we have blueprinted hybrid biopolymer capsules containing drug-loaded vesicles by means of a one-step self-assembly process. These capsules are called "motherships" as each unit features a larger container, the polymer capsule, carrying a payload of smaller vesicular containers, or "babyships," within its lumen. These motherships are self-assembled via electrostatic interactions between oppositely charged polymers/surfactants at the interface of the droplet. Capsule size is simply dictated by drop size, and capsules of sizes 200-5000 µm are produced here. Lipid vesicles, i.e. the babyships, are retained inside motherships due to the diffusional barrier created by the capsule shell. The added transport barrier provided by the vesicle bilayer in addition to the capsule shell provides sustained drug release from the motherships. Furthermore, this one-step drop method allows for the rapid synthesis of soft materials exhibiting structural features over a hierarchy of length scales, from nano-, to micro- to macro-. Thirdly, we have therapeutically functionalized biopolymer films by simply passing a solution of vesicles over the film surface. We deposit films of an associating biopolymer onto patterned solid substrates. Subsequently, these polymer films are able to spontaneously capture therapeutically-loaded vesicles from solution; this is demonstrated both for surfactant as well as lipid vesicles (liposomes). Importantly, it is verified that the vesicles are intact - this is shown both by direct visualization of captured vesicles (via optical and cryo-transmission electron microscopy) as well as through the capture and subsequent disruption of drug filled vesicles. Such therapeutically-functionalized films may be of use in the treatment of chronic wounds and burns. Lastly, we have demonstrated that the addition of a certain biopolymer transforms a suspension of whole blood into a gel. This blueprint is inspired from previous research in our group on the biopolymer-induced gelation of vesicles, which are structurally similar to cells. Upon mixture with heparinized human whole blood, this amphilic biopolymer rapidly forms into an "artificial clot." These mixtures have highly elastic character, with the mixtures able to hold their own weight upon vial inversion. Moreover, the biopolymer shows significant hemorrhage-controlling efficacy in animal injury models. Such biopolymer-cell gelation processes are shown to be reversed via introduction of an amphiphilic supramolecule, thus introducing the novel concept of the "revesible hemostat." Such a hemostatic functionality may be of large and unprecedented use in clinical the treatment of problematic hemorrhage both in trauma and routine surgeries
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