The role of p53 in atherosclerosis

Although the role of the tumour suppressor gene p53 is well known in cancer, recent studies have highlighted a fundamental role for p53 in regulating cells in the advanced atherosclerotic plaque, the major cause of heart attacks and stroke. In particular, p53 is activated in the complex environment of the plaque, in part by DNA damage within the lesion, and regulates growth arrest, cell senescence and apoptosis of vascular smooth muscle cells (VSMCs). The role of endogenous p53 has been determined using p53 knockout in mice developing advanced atherosclerosis, using bone marrow transplant to separate effects on blood cells from vessel wall cells. These studies have produced apparently contradictory and surprising results. In particular, recent studies have identified a role for endogenous p53 in protection of VSMCs from apoptosis, trans-differentiation of bone marrow stromal cells into VSMCs in atherosclerosis, and altering the mode of cell death in the plaque

Performance Test Results of the NASA-457M v2 Hall Thruster

Performance testing of a second generation, 50 kW-class Hall thruster labeled NASA-457M v2 was conducted at the NASA Glenn Research Center. This NASA-designed thruster is an excellent candidate for a solar electric propulsion system that supports human exploration missions. Thruster discharge power was varied from 5 to 50 kW over discharge voltage and current ranges of 200 to 500 V and 15 to 100 A, respectively. Anode efficiencies varied from 0.56 to 0.71. The peak efficiency was similar to that of other state-of-the-art high power Hall thrusters, but outperformed these thrusters at lower discharge voltages. The 0.05 to 0.18 higher anode efficiencies of this thruster compared to its predecessor were primarily due to which of two stable discharge modes the thruster was operated. One stable mode was at low magnetic field strengths, which produced high anode efficiencies, and the other at high magnetic fields where its predecessor was operated. Cathode keeper voltages were always within 2.1 to 6.2 V and cathode voltages were within 13 V of tank ground during high anode efficiency operation. However, during operation at high magnetic fields, cathode-to-ground voltage magnitudes increased dramatically, exceeding 30 V, due to the high axial magnetic field strengths in the immediate vicinity of the centrally-mounted cathode. The peak thrust was 2.3 N and this occurred at a total thruster input power of 50.0 kW at a 500 V discharge voltage. The thruster demonstrated a thrust-to-power range of 76.4 mN/kW at low power to 46.1 mN/kW at full power, and a specific impulse range of 1420 to 2740 s. For a discharge voltage of 300 V, where specific impulses would be about 2000 s, thrust efficiencies varied from 0.57 to 0.63

'Social Labor' and the Marxist Critique of Work

This paper argues that when it comes to thinking about work and labor, Marxism experiences a continued difficulty in holding theory and politics together without reliance on the concept of "social labor": a humanist ideological concept which mystifies the role of social relations in explaining work under capitalism. The evidence for this is collected through a reading of a number of important contributions within the Marxist sociology of work. At its conclusion, the paper turns back to Althusser and his critique of work and ideology in order to point towards the framework for an alternative critique of work that makes a conceptual move away from humanist ideas of alienation and social labor, towards materialist notions of interpellation and social relations

Towards a sociological anthropology: On Theodor Adorno's Contribution to the Theory of Ideology

Adorno's argument in this recently translated essay is that sociology is necessary in order to unlock the ‘epistemological power’ of the concept of ideology. This paper reads Adorno's argument with an Althusserian guilt in order to isolate the theoretically anti-humanist character of this epistemological power. The paper demonstrates how sociology, for Adorno, unlocks this epistemological power by shifting the field of inquiry away from the psychology of the individual subject, towards the “objectively prescribed contexts of delusion” located at the meeting point of specific material social relations. In order to make sense of Adorno's theoretical work here, the paper employs the concept of ‘anthropology’ as developed by Étienne Balibar, in order to demonstrate how Adorno mobilises the concept of ideology in order to think about subjective interpellation in an anti-humanist way, breaking with the vulgar psychology of traditional theories of ideology

The Ideology of Work and the Pandemic in Britain

The celebration of “key workers” in Britain during the pandemic forms the basis of what Althusser described as an “ideology of work,” a largely humanistic ideological machinery deployed in the service of maintaining and reproducing capitalist relations of production in the face of the present crisis. As opposed to a benign expression of national unity in response to a threat, this essay argues that the ideological celebration of key workers in Britain has been crucial to the protection of key accumulation strategies threatened by the crisis and to the neutralization of any potential resistance by those workers endangered by these strategies. This ideology of work has underpinned the implementation of numerous social policies in the service of protecting these relations of production: a fact which this essay argues must be adequately confronted prior to the imagination of alternative social policies and social futures after the pandemic

The status of GEO 600

The GEO 600 laser interferometer with 600m armlength is part of a worldwide network of gravitational wave detectors. GEO 600 is unique in having advanced multiple pendulum suspensions with a monolithic last stage and in employing a signal recycled optical design. This paper describes the recent commissioning of the interferometer and its operation in signal recycled mode

First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

Meson-meson interactions in a nonperturbative chiral approach

A non-perturbative method which combines constraints from chiral symmetry breaking and coupled channel unitarity is used to describe the meson-meson interaction up to about 1.2 GeV. The approach uses the O(p^2) and O(p^4) chiral Lagrangians. The seven free parameters of the O(p^4) Lagrangian are fitted to the data. The results are in good agreement with a vast amount of experimental analyses. The amplitudes develop poles in the complex plane corresponding to the f0, a0, rho, K*, phi, sigma and kappa resonances; the latter two, very broad. The total and partial decay widths of the resonances are also well reproduced. Further extensions and applications of this chiral non-perturbative scheme are also discussed

Overview of the Development of the Solar Electric Propulsion Technology Demonstration Mission 12.5-kW Hall Thruster

NASA is developing mission concepts for a solar electric propulsion technology demonstration mission. A number of mission concepts are being evaluated including ambitious missions to near Earth objects. The demonstration of a high-power solar electric propulsion capability is one of the objectives of the candidate missions under consideration. In support of NASA's exploration goals, a number of projects are developing extensible technologies to support NASA's near and long term mission needs. Specifically, the Space Technology Mission Directorate Solar Electric Propulsion Technology Demonstration Mission project is funding the development of a 12.5-kilowatt magnetically shielded Hall thruster system to support future NASA missions. This paper presents the design attributes of the thruster that was collaboratively developed by the NASA Glenn Research Center and the Jet Propulsion Laboratory. The paper provides an overview of the magnetic, plasma, thermal, and structural modeling activities that were carried out in support of the thruster design. The paper also summarizes the results of the functional tests that have been carried out to date. The planned thruster performance, plasma diagnostics (internal and in the plume), thermal, wear, and mechanical tests are outlined

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012