Development of inflatable structures at the University of Southampton

Inflatable technology for space applications is under continual development and advances in high strength fibres and rigidizable materials have pushed the limitations of these structures. This has lead to their application in deploying large-aperture antennas, reflectors and solar sails. However, many significant advantages can be achieved by combining inflatable structures with structural stiffeners such as tape springs. These advantages include control of the deployment path of the structure while it is inflating (a past weakness of inflatable structure designs), an increased stiffness of the structure once deployed and a reduction in the required inflation volume. Such structures have been previously constructed at the Jet Propulsion Laboratory focusing on large scale booms. However, due to the high efficiency of these designs they are also appealing to small satellite systems. This article outlines ongoing research work performed at the University of Southampton into the field of small satellite hybrid inflatable structures. Inflatable booms have been constructed and combined with tape spring reinforcements to create simple hybrid structures. These structures have been subjected to bending tests and compared directly to an equivalent inflatable tube without tape spring reinforcement. This enables the stiffness benefits to be determined with respect to the added mass of the tape springs. The paper presents these results, which leads to an initial performance assessment of these structures

Therapie der Myositiden

Zusammenfassung: Zu den idiopathischen inflammatorischen Myositiden zählen die Dermatomyositis (DM), Polymyositis (PM), die Einschlusskörperchenmyositis ("inclusion body myositis", IBM) und die nekrotisierende autoimmune Myopathie (NAM). Bei DM und PM werden initial Glukokortikosteroide empfohlen. Steroid-sparende Immunsuppressiva wie Azathioprin, Methotrexat oder CyclosporinA werden bei ungenügendem Ansprechen verabreicht, bei drohenden Steroidnebenwirkungen oder wenn die initiale Prognose ungünstig ist. Die Therapie kann auch mit intravenösen Immunglobulinen (IVIG) eskaliert werden. Tacrolimus und Mycophenolat Mofetil (MMF) waren in kleineren Fallserien effektiv. Cyclophosphamid sollte therapierefraktären Patienten vorbehalten bleiben. Auch MMF kann mit IVIG kombiniert werden, um die Therapie zu intensivieren. Die Evidenz für Rituximab ist für den Routineeinsatz ungenügend. TNF-α-Inhibitoren und Plasmapherese haben nicht überzeugt. Die kutanen Manifestationen der DM reagieren auf Sonnenschutz, Antimalariamittel, topische Glukokortikosteroide sowie Calcineurininhibitoren. Bei der NAM sollten Statine abgesetzt und Prednison mit Immunsuppressiva initiiert werden. Bei der IBM wird ein Therapieversuch mit Prednison, Methotrexat oder Azathioprin bei Kreatinkinase-Erhöhung oder entzündlichem Infiltrat empfohlen. In jedem Stadium der Myositiden ist Physiotherapie nützlic

New Upper Limits on the Tau Neutrino Mass from Primordial Helium Considerations

In this paper we reconsider recently derived bounds on $MeV$ tau neutrinos, taking into account previously unaccounted for effects. We find that, assuming that the neutrino life-time is longer than $O(100~sec)$, the constraint $N_{eff}<3.6$ rules out $\nu_{\tau}$ masses in the range $0.5~(MeV)<m_{\nu_\tau}<35~(MeV)$ for Majorana neutrinos and $0.74~(MeV)<m_{\nu_\tau}<35~(MeV)$ for Dirac neutrinos. Given that the present laboratory bound is 35 MeV, our results lower the present bound to $0.5$ and $0.74$ for Majorana and Dirac neutrinos respectively.Comment: 9 pages (2 figures available upon request), UM-AC-93-0

Developing a tradition of scholarship : the emergence and evolution of the AHRD-sponsored journals

The Problem Research and theory are the lifeblood of academic disciplines along with the peer-reviewed journals that disseminate such scholarship. Journals become critical repositories that capture the histories and evolution of such disciplines, and their scholarly contributions generate new knowledge that can stimulate further research and improve practice. The Academy of Human Resource Development (AHRD) sponsors four peer-reviewed journals that have contributed to the birth and evolution of the discipline of human resource development (HRD). Yet, little is known about how they came into being, how they have evolved, and what their impact has been within the field of HRD. The Solution This article captures the histories of the emergence and evolution of the four refereed journals sponsored by the AHRD through the unique voices of current and recent past editors of these journals. It then considers common themes of scholarship across the four journals that have helped to shape HRD. The Stakeholders Students, researchers, and scholar-practitioners in the field of HRD and related fields who are interested in learning more about the histories of the journals sponsored by the AHRD, along with their contributions to the scholarship in HRD, will benefit from reading this article

Electron transport in the dye sensitized nanocrystalline cell

Dye sensitised nanocrystalline solar cells (Gr\"{a}tzel cells) have achieved solar-to-electrical energy conversion efficiencies of 12% in diffuse daylight. The cell is based on a thin film of dye-sensitised nanocrystalline TiO$_2$ interpenetrated by a redox electrolyte. The high surface area of the TiO$_2$ and the spectral characteristics of the dye allow the device to harvest 46% of the solar energy flux. One of the puzzling features of dye-sensitised nano-crystalline solar cells is the slow electron transport in the titanium dioxide phase. The available experimental evidence as well as theoretical considerations suggest that the driving force for electron collection at the substrate contact arises primarily from the concentration gradient, ie the contribution of drift is negligible. The transport of electrons has been characterised by small amplitude pulse or intensity modulated illumination. Here, we show how the transport of electrons in the Gr\"{a}tzel cell can be described quantitatively using trap distributions obtained from a novel charge extraction method with a one-dimensional model based on solving the continuity equation for the electron density. For the first time in such a model, a back reaction with the I$_3^-$ ions in the electrolyte that is second order in the electron density has been included.Comment: 6 pages, 5 figures, invited talk at the workshop 'Nanostructures in Photovoltaics' to appear in Physica

Excitation of High-Spin States by Inelastic Proton Scattering

This work was supported by National Science Foundation Grant PHY 76-84033 and Indiana Universit

Excitation of High-Spin States by Inelastic Proton Scattering

This work was supported by National Science Foundation Grant PHY 75-00289 and Indiana Universit

NOD/SCID-GAMMA Mice Are an Ideal Strain to Assess the Efficacy of Therapeutic Agents Used in the Treatment of Myeloma Bone Disease

Animal models of multiple myeloma vary in terms of consistency of onset, degree of tumour burden and degree of myeloma bone disease. Here we describe five pre-clinical models of myeloma in NOD/SCID-GAMMA mice to specifically study the effects of therapeutic agents on myeloma bone disease. Groups of 7–8 week old female irradiated NOD/SCID-GAMMA mice were injected intravenously via the tail vein with either 1x106 JJN3, U266, XG-1 or OPM-2 human myeloma cell lines or patient-derived myeloma cells. At the first signs of morbidity in each tumour group all animals were sacrificed. Tumour load was measured by histological analysis, and bone disease was assessed by micro-CT and standard histomorphometric methods. Mice injected with JJN3, U266 or OPM-2 cells showed high tumour bone marrow infiltration of the long bones with low variability, resulting in osteolytic lesions. In contrast, mice injected with XG-1 or patient-derived myeloma cells showed lower tumour bone marrow infiltration and less bone disease with high variability. Injection of JJN3 cells into NOD/SCID-GAMMA mice resulted in an aggressive, short-term model of myeloma with mice exhibiting signs of morbidity 3 weeks later. Treating these mice with zoledronic acid at the time of tumour cell injection or once tumour was established prevented JJN3-induced bone disease but did not reduce tumour burden, whereas, carfilzomib treatment given once tumour was established significantly reduced tumour burden. Injection of U266, XG-1, OPM-2 and patient-derived myeloma cells resulted in less aggressive longer-term models of myeloma with mice exhibiting signs of morbidity 8 weeks later. Treating U266-induced disease with zoledronic acid prevented the formation of osteolytic lesions and trabecular bone loss as well as reducing tumour burden whereas, carfilzomib treatment only reduced tumour burden. In summary, JJN3, U266 or OPM-2 cells injected into NOD/SCID-GAMMA mice provide robust models to study anti-myeloma therapies, particularly those targeting myeloma bone disease