309 research outputs found

    The Effects of the Division of the City of Lloydminster by the Alberta-Saskatchewan Inter-Provincial Boundary

    Get PDF
    L'article expose les consĂ©quences, sur le dĂ©veloppement de Lloydminster, de la localisation de la ligne frontiĂšre Alberta - Saskatchewan qui coupe cette citĂ© en deux. Les problĂšmes de la duplication des services et des Ă©quipements publics encourageaient, dans les premiĂšres annĂ©es d'existence de la communautĂ©, les essais de fusion des deux parties de Lloydminster. Cette fusion a Ă©tĂ© accomplie en 1930, et la citĂ© fonctionne sous une lĂ©gislation spĂ©ciale, le « Lloydminster Charter ». Les inefficacitĂ©s inhĂ©rentes Ă  cette division subsistent encore, en particulier pour le gouvernement municipal, de mĂȘme que les dĂ©savantages pour les activitĂ©s commerciales, parce que la lĂ©gislation provinciale de l'Alberta ou de la Saskatchewan s'applique aux individus, selon le cĂŽtĂ© de la ligne frontiĂšre oĂč ils rĂ©sident, travaillent, font leurs achats, ou possĂšdent des industries. La taxe de vente levĂ©e par le gouvernement de la Saskatchewan reste un problĂšme pour les marchands et les habitants. La majeure partie du dĂ©veloppement commercial et industriel se situe Ă  l'ouest de la citĂ©, c'est-Ă -dire en Alberta. Les sociĂ©tĂ©s industrielles et les marchands, les gens de mĂ©tier et les habitants veulent que la citĂ© soit situĂ©e entiĂšrement en Alberta ou entiĂšrement en Saskatchewan pour supprimer les inefficacitĂ©s et les irritations qui rĂ©sultent de la division de la citĂ© par la ligne frontiĂšre.The paper traces the effects of the superimposed inter-provincial boundary line on the development of Lloydminster. Duplication of public services, and other difficulties encouraged early efforts to amalgamate the community under one jurisdiction. This was accomplished in 1930 and the city is operated under special legislation which is called the « Lloydminster Charter ». Inherent inefficiencies still remain for civic government as well as disadvantages for private enterprises as the provincial legislation of Alberta or Saskatchewan prevails depending upon which side of the boundary a person resides, works, shops, or an economic enterprise is located. The sales tax levied on most purchases by the Saskatchewan Government remains a problem for retailers and citizens. Most of the commercial and industrial development is occurring on the Alberta side of the City. There is evidence that industrial and commercial companies, professional people and residents, would prefer the City to be either in Alberta or Saskatchewan in order to eradicate the inefficiencies and irritations caused by the division of the city by the boundary

    Optical modulation in a resonant tunneling relaxation oscillator

    Get PDF
    We report high-speed optical modulation in a resonant tunneling relaxation oscillator consisting of a resonant tunneling diode (RTD) integrated with a unipolar optical waveguide and incorporated in a package with a coplanar waveguide transmission line. When appropriately biased, the RTD can provide wide-bandwidth electrical gain. For wavelengths near the material band edge, small changes of the applied voltage give rise to large, high-speed electroabsorption modulation of the light. We have observed optical modulation at frequencies up to 14 GHz, associated with subharmonic injection locking of the RTD oscillation at the fundamental mode of the coplanar transmission line, as well as generation of 33 ps optical pulses due to relaxation oscillation

    Optical modulation at around 1550 nm in an InGaAlAs optical waveguide containing an InGaAs/AlAs resonant tunneling diode

    Get PDF
    We report electroabsorption modulation of light at around 1550 nm in a unipolar InGaAlAs optical waveguide containing an InGaAs/AlAs double-barrier resonant tunneling diode ~RTD!. The RTD peak-to-valley transition increases the electric ïŹeld across the waveguide, which shifts the core material absorption band edge to longer wavelengths via the Franz–Keldysh effect, thus changing the light-guiding characteristics of the waveguide. Low-frequency characterization of a device shows modulation up to 28 dB at 1565 nm. When dc biased close to the negative differential conductance region, the RTD optical waveguide behaves as an electroabsorption modulator integrated with a wide bandwidth electrical ampliïŹer, offering a potential advantage over conventional pn modulators

    On the shopfloor: exploring the impact of teacher trade unions on school-based industrial relations

    Get PDF
    Teachers are highly unionised workers and their trade unions exert an important influence on the shaping and implementation of educational policy. Despite this importance there is relatively little analysis of the impact of teacher trade unions in educational management literature. Very little empirical research has sought to establish the impact of teacher unions at school level. In an era of devolved management and quasi-markets this omission is significant. New personnel issues continue to emerge at school level and this may well generate increased trade union activity at the workplace. This article explores the extent to which devolved management is drawing school-based union representation into a more prominent role. It argues that whilst there can be significant differences between individual schools, increased school autonomy is raising the profile of trade union activity in the workplace, and this needs to be better reflected in educational management research

    Dura mater-associated Creutzfeldt-Jakob disease:experience from surveillance in the UK

    Get PDF
    Between 1970 and 2003, seven cases of human dura mater‐associated Creutzfeldt–Jakob disease (CJD) were identified in the UK. Furthermore, we identified a case of CJD in a porcine dura graft recipient. The mean incubation period of the human dura mater cases was 93 (range 45–177) months. The clinico‐pathological features of the cases are described and compared with cases previously reported in the world literature

    Cathepsin D SNP associated with increased risk of variant Creutzfeldt-Jakob disease

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Variant Creutzfeldt-Jakob disease (vCJD) originally resulted from the consumption of foodstuffs contaminated by bovine spongiform encephalopathy (BSE) material, with 163 confirmed cases in the UK to date. Many thousands are likely to have been exposed to dietary infection and so it is important (for surveillance, epidemic modelling, public health and understanding pathogenesis) to identify genetic factors that may affect individual susceptibility to infection. This study looked at a polymorphism in the cathepsin D gene (refSNP ID: rs17571) previously examined in Alzheimer's disease (AD).</p> <p>Methods</p> <p>Blood samples taken from 110 vCJD patients were tested for the C-T base change, and genotype data were compared with published frequencies for a control population using multiple logistic regression.</p> <p>Results</p> <p>There was a significant excess of the cathepsin D polymorphism TT genotype in the vCJD cohort compared to controls. The TT genotype was found to have a 9.75 fold increase in risk of vCJD compared to the CT genotype and a 10.92 fold increase compared to the CC genotype.</p> <p>Conclusion</p> <p>This mutation event has been observed to alter the protease activity of the cathepsin D protein and has been linked to an increase in amyloid beta plaque formation in AD. vCJD neuropathology is characterised by the presence of amyloid plaques, formed from the prion protein, and therefore alterations in the amyloid processing activity of cathepsin D may affect the neuropathogenesis of this disease.</p

    Cascaded two-photon nonlinearity in a one-dimensional waveguide with multiple two-level emitters

    Full text link
    We propose and theoretically investigate a model to realize cascaded optical nonlinearity with few atoms and photons in one-dimension (1D). The optical nonlinearity in our system is mediated by resonant interactions of photons with two-level emitters, such as atoms or quantum dots in a 1D photonic waveguide. Multi-photon transmission in the waveguide is nonreciprocal when the emitters have different transition energies. Our theory provides a clear physical understanding of the origin of nonreciprocity in the presence of cascaded nonlinearity. We show how various two-photon nonlinear effects including spatial attraction and repulsion between photons, background fluorescence can be tuned by changing the number of emitters and the coupling between emitters (controlled by the separation).Comment: 6 pages, 4 figure

    Rapidly progressive dementia with thalamic degeneration and peculiar cortical prion protein immunoreactivity, but absence of proteinase K resistant PrP: a new disease entity?

    Get PDF
    BACKGROUND: Human prion diseases are a group of rare fatal neurodegenerative conditions with well-developed clinical and neuropathological diagnostic criteria. Recent observations have expanded the spectrum of prion diseases beyond the classically recognized forms. RESULTS: In the present study we report six patients with a novel, apparently sporadic disease characterised by thalamic degeneration and rapidly progressive dementia (duration of illness 2-12 months; age at death: 55-81 years). Light and electron microscopic immunostaining for the prion protein (PrP) revealed a peculiar intraneuritic distribution in neocortical regions. Proteinase K resistant PrP (PrPres) was undetectable by Western blotting in frontal cortex from the three cases with frozen tissue, even after enrichment for PrPres by centrifugation or by phosphotungstic acid precipitation. Conformation-dependent immunoassay analysis using a range of PK digestion conditions (and no PK digestion) produced only very limited evidence of meaningful D-N (denatured/native) values, indicative of the presence of disease-associated PrP (PrPSc) in these cases, when the results were compared with appropriate negative control groups. CONCLUSIONS: Our observation expands the spectrum of conditions associated with rapidly progressive dementia and may have implications for the understanding of the pathogenesis of prion diseases

    Anti-cancer effects and mechanism of actions of aspirin analogues in the treatment of glioma cancer

    Get PDF
    INTRODUCTION: In the past 25 years only modest advancements in glioma treatment have been made, with patient prognosis and median survival time following diagnosis only increasing from 3 to 7 months. A substantial body of clinical and preclinical evidence has suggested a role for aspirin in the treatment of cancer with multiple mechanisms of action proposed including COX 2 inhibition, down regulation of EGFR expression, and NF-ÎșB signaling affecting Bcl-2 expression. However, with serious side effects such as stroke and gastrointestinal bleeding, aspirin analogues with improved potency and side effect profiles are being developed. METHOD: Effects on cell viability following 24 hr incubation of four aspirin derivatives (PN508, 517, 526 and 529) were compared to cisplatin, aspirin and di-aspirin in four glioma cell lines (U87 MG, SVG P12, GOS – 3, and 1321N1), using the PrestoBlue assay, establishing IC50 and examining the time course of drug effects. RESULTS: All compounds were found to decrease cell viability in a concentration and time dependant manner. Significantly, the analogue PN517 (IC50 2mM) showed approximately a twofold increase in potency when compared to aspirin (3.7mM) and cisplatin (4.3mM) in U87 cells, with similar increased potency in SVG P12 cells. Other analogues demonstrated similar potency to aspirin and cisplatin. CONCLUSION: These results support the further development and characterization of novel NSAID derivatives for the treatment of glioma
    • 

    corecore