57 research outputs found

    Attitude control system for sounding rockets Patent

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    Development of attitude control system for sounding rocket stabilization during ballistic phase of fligh

    Capturing protest in urban environments:The ‘police kettle’ as a territorial strategy

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    ‘Kettling’ has emerged in recent decades as an established, if controversial, tactic of public order policing. Departing from a historical emphasis on dispersal, kettling instead acts to contain protesters within a police cordon for sustained periods of time. This article elaborates upon the spatial and temporal logics of kettling by investigating the conditions of is historical emergence. We argue that kettling should be understood as a territorial strategy that co-evolved in relation to forms of disruptive protest. Whereas techniques of crowd dispersal serve to diffuse a unified collective, ‘kettling’ aims to capture the volatile intensities of public dissent and exhaust its political energies. Drawing on police manuals, media coverage, accounts from activists and expert interviews, we show how the ‘kettle’ re-territorializes protest by acting on its spatio-temporal and affective constitution. By fabricating an inner outside of the urban milieu, freezing the time of collective mobilization and inducing debilitating affects such as fear and boredom, kettling intervenes into the scene of political subjectification that each congregation of protesting bodies seeks to fashion

    A Measurement of the CMB Temperature Power Spectrum and Constraints on Cosmology from the SPT-3G 2018 TT/TE/EE Data Set

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    We present a sample-variance-limited measurement of the temperature power spectrum (TTTT) of the cosmic microwave background (CMB) using observations of a  ⁣1500deg2\sim\! 1500 \,\mathrm{deg}^2 field made by SPT-3G in 2018. We report multifrequency power spectrum measurements at 95, 150, and 220GHz covering the angular multipole range 750<3000750 \leq \ell < 3000. We combine this TTTT measurement with the published polarization power spectrum measurements from the 2018 observing season and update their associated covariance matrix to complete the SPT-3G 2018 TT/TE/EETT/TE/EE data set. This is the first analysis to present cosmological constraints from SPT TTTT, TETE, and EEEE power spectrum measurements jointly. We blind the cosmological results and subject the data set to a series of consistency tests at the power spectrum and parameter level. We find excellent agreement between frequencies and spectrum types and our results are robust to the modeling of astrophysical foregrounds. We report results for Λ\LambdaCDM and a series of extensions, drawing on the following parameters: the amplitude of the gravitational lensing effect on primary power spectra ALA_\mathrm{L}, the effective number of neutrino species NeffN_{\mathrm{eff}}, the primordial helium abundance YPY_{\mathrm{P}}, and the baryon clumping factor due to primordial magnetic fields bb. We find that the SPT-3G 2018 T/TE/EET/TE/EE data are well fit by Λ\LambdaCDM with a probability-to-exceed of 15%15\%. For Λ\LambdaCDM, we constrain the expansion rate today to H0=68.3±1.5kms1Mpc1H_0 = 68.3 \pm 1.5\,\mathrm{km\,s^{-1}\,Mpc^{-1}} and the combined structure growth parameter to S8=0.797±0.042S_8 = 0.797 \pm 0.042. The SPT-based results are effectively independent of Planck, and the cosmological parameter constraints from either data set are within <1σ<1\,\sigma of each other. (abridged)Comment: 35 Pages, 17 Figures, 11 Table

    A Measurement of Gravitational Lensing of the Cosmic Microwave Background Using SPT-3G 2018 Data

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    We present a measurement of gravitational lensing over 1500 deg2^2 of the Southern sky using SPT-3G temperature data at 95 and 150 GHz taken in 2018. The lensing amplitude relative to a fiducial Planck 2018 Λ\LambdaCDM cosmology is found to be 1.020±0.0601.020\pm0.060, excluding instrumental and astrophysical systematic uncertainties. We conduct extensive systematic and null tests to check the robustness of the lensing measurements, and report a minimum-variance combined lensing power spectrum over angular multipoles of 50<L<200050<L<2000, which we use to constrain cosmological models. When analyzed alone and jointly with primary cosmic microwave background (CMB) spectra within the Λ\LambdaCDM model, our lensing amplitude measurements are consistent with measurements from SPT-SZ, SPTpol, ACT, and Planck. Incorporating loose priors on the baryon density and other parameters including uncertainties on a foreground bias template, we obtain a 1σ1\sigma constraint on σ8Ωm0.25=0.595±0.026\sigma_8 \Omega_{\rm m}^{0.25}=0.595 \pm 0.026 using the SPT-3G 2018 lensing data alone, where σ8\sigma_8 is a common measure of the amplitude of structure today and Ωm\Omega_{\rm m} is the matter density parameter. Combining SPT-3G 2018 lensing measurements with baryon acoustic oscillation (BAO) data, we derive parameter constraints of σ8=0.810±0.033\sigma_8 = 0.810 \pm 0.033, S8σ8(Ωm/0.3)0.5=0.836±0.039S_8 \equiv \sigma_8(\Omega_{\rm m}/0.3)^{0.5}= 0.836 \pm 0.039, and Hubble constant H0=68.81.6+1.3H_0 =68.8^{+1.3}_{-1.6} km s1^{-1} Mpc1^{-1}. Using CMB anisotropy and lensing measurements from SPT-3G only, we provide independent constraints on the spatial curvature of ΩK=0.0140.026+0.023\Omega_{K} = 0.014^{+0.023}_{-0.026} (95% C.L.) and the dark energy density of ΩΛ=0.7220.026+0.031\Omega_\Lambda = 0.722^{+0.031}_{-0.026} (68% C.L.). When combining SPT-3G lensing data with SPT-3G CMB anisotropy and BAO data, we find an upper limit on the sum of the neutrino masses of mν<0.30\sum m_{\nu}< 0.30 eV (95% C.L.)

    Overview of the FTU results

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    Since the 2016 IAEA Fusion Energy Conference, FTU operations have been mainly devoted to experiments on runaway electrons and investigations into a tin liquid limiter; other experiments have involved studies of elongated plasmas and dust. The tearing mode onset in the high density regime has been studied by means of the linear resistive code MARS, and the highly collisional regimes have been investigated. New diagnostics, such as a runaway electron imaging spectroscopy system for in-flight runaway studies and a triple Cherenkov probe for the measurement of escaping electrons, have been successfully installed and tested, and new capabilities of the collective Thomson scattering and the laser induced breakdown spectroscopy diagnostics have been explored

    Overview of the TCV tokamak experimental programme

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    The tokamak a configuration variable (TCV) continues to leverage its unique shaping capabilities, flexible heating systems and modern control system to address critical issues in preparation for ITER and a fusion power plant. For the 2019-20 campaign its configurational flexibility has been enhanced with the installation of removable divertor gas baffles, its diagnostic capabilities with an extensive set of upgrades and its heating systems with new dual frequency gyrotrons. The gas baffles reduce coupling between the divertor and the main chamber and allow for detailed investigations on the role of fuelling in general and, together with upgraded boundary diagnostics, test divertor and edge models in particular. The increased heating capabilities broaden the operational regime to include T (e)/T (i) similar to 1 and have stimulated refocussing studies from L-mode to H-mode across a range of research topics. ITER baseline parameters were reached in type-I ELMy H-modes and alternative regimes with \u27small\u27 (or no) ELMs explored. Most prominently, negative triangularity was investigated in detail and confirmed as an attractive scenario with H-mode level core confinement but an L-mode edge. Emphasis was also placed on control, where an increased number of observers, actuators and control solutions became available and are now integrated into a generic control framework as will be needed in future devices. The quantity and quality of results of the 2019-20 TCV campaign are a testament to its successful integration within the European research effort alongside a vibrant domestic programme and international collaborations

    Significance of vascular endothelial growth factor in growth and peritoneal dissemination of ovarian cancer

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    Vascular endothelial growth factor (VEGF) is a key regulator of angiogenesis which drives endothelial cell survival, proliferation, and migration while increasing vascular permeability. Playing an important role in the physiology of normal ovaries, VEGF has also been implicated in the pathogenesis of ovarian cancer. Essentially by promoting tumor angiogenesis and enhancing vascular permeability, VEGF contributes to the development of peritoneal carcinomatosis associated with malignant ascites formation, the characteristic feature of advanced ovarian cancer at diagnosis. In both experimental and clinical studies, VEGF levels have been inversely correlated with survival. Moreover, VEGF inhibition has been shown to inhibit tumor growth and ascites production and to suppress tumor invasion and metastasis. These findings have laid the basis for the clinical evaluation of agents targeting VEGF signaling pathway in patients with ovarian cancer. In this review, we will focus on VEGF involvement in the pathophysiology of ovarian cancer and its contribution to the disease progression and dissemination

    Physics research on the TCV tokamak facility: from conventional to alternative scenarios and beyond

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    The research program of the TCV tokamak ranges from conventional to advanced-tokamak scenarios and alternative divertor configurations, to exploratory plasmas driven by theoretical insight, exploiting the device’s unique shaping capabilities. Disruption avoidance by real-time locked mode prevention or unlocking with electron-cyclotron resonance heating (ECRH) was thoroughly documented, using magnetic and radiation triggers. Runaway generation with high-Z noble-gas injection and runaway dissipation by subsequent Ne or Ar injection were studied for model validation. The new 1 MW neutral beam injector has expanded the parameter range, now encompassing ELMy H-modes in an ITER-like shape and nearly non-inductive H-mode discharges sustained by electron cyclotron and neutral beam current drive. In the H-mode, the pedestal pressure increases modestly with nitrogen seeding while fueling moves the density pedestal outwards, but the plasma stored energy is largely uncorrelated to either seeding or fueling. High fueling at high triangularity is key to accessing the attractive small edge-localized mode (type-II) regime. Turbulence is reduced in the core at negative triangularity, consistent with increased confinement and in accord with global gyrokinetic simulations. The geodesic acoustic mode, possibly coupled with avalanche events, has been linked with particle flow to the wall in diverted plasmas. Detachment, scrape-off layer transport, and turbulence were studied in L- and H-modes in both standard and alternative configurations (snowflake, super-X, and beyond). The detachment process is caused by power ‘starvation’ reducing the ionization source, with volume recombination playing only a minor role. Partial detachment in the H-mode is obtained with impurity seeding and has shown little dependence on flux expansion in standard single-null geometry. In the attached L-mode phase, increasing the outer connection length reduces the in–out heat-flow asymmetry. A doublet plasma, featuring an internal X-point, was achieved successfully, and a transport barrier was observed in the mantle just outside the internal separatrix. In the near future variable-configuration baffles and possibly divertor pumping will be introduced to investigate the effect of divertor closure on exhaust and performance, and 3.5 MW ECRH and 1 MW neutral beam injection heating will be added

    ALMS1 and Alström syndrome: a recessive form of metabolic, neurosensory and cardiac deficits

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