5,211 research outputs found

    INTRODUCTION

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    Agribusiness,

    The Origins of Political Policing in Canada: Class, Law, and the Burden of Empire

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    This essay examines the origins of the Canadian secret service from the 1860s to the Great War. During this time, the Canadian government faced political challenges from Irish republicans and South Asian radicals. Both groups sought to liberate their home countries-Ireland and India-from British rule by promoting the idea of independence and the necessity of militant tactics amongst their respective immigrant communities in North America. Faced with this subversive activity, which had both domestic and international implications, the government created a secret service to gather political intelligence. Significantly, the government\u27s political response was shaped decisively by its status as an outpost of the British Empire. Not only did Canada make use of the imperial civil service to confront this danger, but the very subversion it faced was a product of the mother country\u27s own history of imperialism and colonialism

    The Origins of Political Policing in Canada: Class, Law, and the Burden of Empire

    Get PDF
    This essay examines the origins of the Canadian secret service from the 1860s to the Great War. During this time, the Canadian government faced political challenges from Irish republicans and South Asian radicals. Both groups sought to liberate their home countries-Ireland and India-from British rule by promoting the idea of independence and the necessity of militant tactics amongst their respective immigrant communities in North America. Faced with this subversive activity, which had both domestic and international implications, the government created a secret service to gather political intelligence. Significantly, the government\u27s political response was shaped decisively by its status as an outpost of the British Empire. Not only did Canada make use of the imperial civil service to confront this danger, but the very subversion it faced was a product of the mother country\u27s own history of imperialism and colonialism

    Feasibility study of an orbiting laboratory for testing CSI technology

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    A concept for an orbiting laboratory for testing Controls-Structures Integration (CSI) technology is described. The CSI-Star concept reflects a lower cost, higher risk approach. The concept supports demonstration and validation testing for critical CSI technologies at a cost of 20Mto20M to 26M with a 1-year reliability of approximately 0.9. The Ball Aerospace QuickStar bus is the carrier for the CSI test article. QuickStar is launched as a secondary payload on the McDonnell Douglas Delta 2. The QuickStar/Delta 2 approach is flight proven. The CSI test article is a 20 foot, 1 Hz, truss beam which is deployed from the QuickStar bus. The test article is well instrumented for quality system identification. The laboratory provides three layers of active control consisting of global vibration suppression along the truss beam, vibration isolation between the beam and instrument platforms, and vibration compensation through the use of gimbaled platforms which point lasers relative to optical sensor targets. The configuration simulates the dynamics of multi-instrument science platforms such as those of the Earth Observation System (EOS) while maintaining strong ties to astrophysics missions such as the Optical Interferometer. Uplink/downlink services and a reprogrammable computer provide flexibility for long-term investigations by members of the CSI community (NASA, DoD, academia, and industry). CSI-Star fills the gap between short-term experiments, which have been conducted primarily on the Shuttle, and future science missions which require the technology. The on-orbit maturity of CSI technology must be established to obtain acceptance by project managers and to promote injection of the technology into future science missions

    Heat shock factor 1 regulates lifespan as distinct from disease onset in prion disease

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    Prion diseases are fatal, transmissible, neurodegenerative diseases caused by the misfolding of the prion protein (PrP). At present, the molecular pathways underlying prion-mediated neurotoxicity are largely unknown. We hypothesized that the transcriptional regulator of the stress response, heat shock factor 1 (HSF1), would play an important role in prion disease. Uninoculated HSF1 knockout (KO) mice used in our study do not show signs of neurodegeneration as assessed by survival, motor performance, or histopathology. When inoculated with Rocky Mountain Laboratory (RML) prions HSF1 KO mice had a dramatically shortened lifespan, succumbing to disease ≈20% faster than controls. Surprisingly, both the onset of home-cage behavioral symptoms and pathological alterations occurred at a similar time in HSF1 KO and control mice. The accumulation of proteinase K (PK)-resistant PrP also occurred with similar kinetics and prion infectivity accrued at an equal or slower rate. Thus, HSF1 provides an important protective function that is specifically manifest after the onset of behavioral symptoms of prion disease

    Scent of the familiar: An fMRI study of canine brain responses to familiar and unfamiliar human and dog odors

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    Understanding dogs’ perceptual experience of both conspecifics and humans is important to understand how dogs evolved and the nature of their relationships with humans and other dogs. Olfaction is believed to be dogs’ most powerful and perhaps important sense and an obvious place to begin for the study of social cognition of conspecifics and humans. We used fMRI in a cohort of dogs (N = 12) that had been trained to remain motionless while unsedated and unrestrained in the MRI. By presenting scents from humans and conspecifics, we aimed to identify the dimensions of dogs’ responses to salient biological odors – whether they are based on species (dog or human), familiarity, or a specific combination of factors. We focused our analysis on the dog\u27s caudate nucleus because of its well-known association with positive expectations and because of its clearly defined anatomical location. We hypothesized that if dogs’ primary association to reward, whether it is based on food or social bonds, is to humans, then the human scents would activate the caudate more than the conspecific scents. Conversely, if the smell of conspecifics activated the caudate more than the smell of humans, dogs’ association to reward would be stronger to their fellow canines. Five scents were presented (self, familiar human, strange human, familiar dog, strange dog). While the olfactory bulb/peduncle was activated to a similar degree by all the scents, the caudate was activated maximally to the familiar human. Importantly, the scent of the familiar human was not the handler, meaning that the caudate response differentiated the scent in the absence of the person being present. The caudate activation suggested that not only did the dogs discriminate that scent from the others, they had a positive association with it. This speaks to the power of the dog\u27s sense of smell, and it provides important clues about the importance of humans in dogs’ lives

    Analysis of the radiation flux profile along a PV through concentrator

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    The primary advantage of a PV concentrator is that concentrating light allows a significant reduction in the area of solar cell coverage, the main cost driver in a flat plate system. PV systems, whether flat plate or concentrating, normally have groups of solar cells connected in series in order to increase voltage and limit current. However, low illumination on a single cell proportionally reduces its current, and hence affects the performance of all other cells in series. Ideally, a reflective PV concentrator system will have high concentration, a uniform flux distribution, and low cost. However, it is difficult to obtain these three conditions simultaneously, as cost tends to increase with better mirror quality, improved tracking accuracy, and the use of secondary flux modifiers. Linear concentrators have the advantage of simpler and cheaper tracking and support structures than dishes; however, achieving a consistent flux profile on every cell along the focal line is challenging. The aim of this paper is to present results of direct measurements of the flux profile along the length of a single axis tracking trough, and to develop simulation techniques that allow the reasons for peaks and troughs in the flux profile to be better understood

    Kepler-445, Kepler-446 And The Occurrence Of Compact Multiples Orbiting Mid-M Dwarf Stars

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    We confirm and characterize the exoplanetary systems Kepler-445 and Kepler-446: two mid-M dwarf stars, each with multiple, small, short-period transiting planets. Kepler-445 is a metal-rich ([ Fe/H] = + 0.25 0.10) M4 dwarf with three transiting planets, and Kepler-446 is a metal-poor ([ Fe/H] = -0.30 0.10) M4 dwarf also with three transiting planets. Kepler-445c is similar toGJ 1214b: both in planetary radius and the properties of the host star. The Kepler-446 system is similar to the Kepler-42 system: both are metal-poor with large galactic space velocities and three short-period, likely rocky transiting planets that were initially assigned erroneously large planet-to-star radius ratios. We independently determined stellar parameters from spectroscopy and searched for and fitted the transit light curves for the planets, imposing a strict prior on stellar density in order to remove correlations between the fitted impact parameter and planet-to-star radius ratio for short-duration transits. Combining Kepler-445, Kepler-446, and Kepler-42, and isolating all mid-M dwarf stars observed by Kepler with the precision necessary to detect similar systems, we calculate that 21+ 7 -5 % of mid-M dwarf stars host compact multiples ( multiple planets with periods of less than 10 days) for a wide range of metallicities. We suggest that the inferred planet masses for these systems support highly efficient accretion of protoplanetary disk metals by mid-M dwarf protoplanets.NSF DGE1144152, AST-1005313NASA NAS5-26555NASA Office of Space Science NNX13AC07GAstronom

    Castable Amorphous Metal Mirrors and Mirror Assemblies

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    A revolutionary way to produce a mirror and mirror assembly is to cast the entire part at once from a metal alloy that combines all of the desired features into the final part: optical smoothness, curvature, flexures, tabs, isogrids, low CTE, and toughness. In this work, it has been demonstrated that castable mirrors are possible using bulk metallic glasses (BMGs, also called amorphous metals) and BMG matrix composites (BMGMCs). These novel alloys have all of the desired mechanical and thermal properties to fabricate an entire mirror assembly without machining, bonding, brazing, welding, or epoxy. BMGs are multi-component metal alloys that have been cooled in such a manner as to avoid crystallization leading to an amorphous (non-crystalline) microstructure. This lack of crystal structure and the fact that these alloys are glasses, leads to a wide assortment of mechanical and thermal properties that are unlike those observed in crystalline metals. Among these are high yield strength, carbide-like hardness, low melting temperatures (making them castable like aluminum), a thermoplastic processing region (for improving smoothness), low stiffness, high strength-to-weight ratios, relatively low CTE, density similar to titanium alloys, high elasticity and ultra-smooth cast parts (as low as 0.2-nm surface roughness has been demonstrated in cast BMGs). BMGMCs are composite alloys that consist of a BMG matrix with crystalline dendrites embedded throughout. BMGMCs are used to overcome the typically brittle failure observed in monolithic BMGs by adding a soft phase that arrests the formation of cracks in the BMG matrix. In some cases, BMGMCs offer superior castability, toughness, and fatigue resistance, if not as good a surface finish as BMGs. This work has demonstrated that BMGs and BMGMCs can be cast into prototype mirrors and mirror assemblies without difficulty
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