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Experimental configuration of direct drive cylindrical implosions on the Omega Laser
Details about the cylindrical implosions using direct-drive irradiation on the OMEGA Laser facility are provided. The experimental configuration, including orientation, construction, and mounting of the targets is described. An attempt to characterize the modulation transfer function of the primary x-ray framing camera diagnostic results in insufficient exposure contrast but relative agreement with other determinations. The x-ray intensity of the titanium backlighter driven by the 2.5-nsec linear ramp of the laser beams is described, and the relative intensity on film is compared to similar Nova experiments. The parallax effects of different length marker layers of high-opacity dichloropolystyrene is measured, resulting in the conclusion that the marker layer length should be matched to the laser drive illumination profile
An integrated approach to modelling the fluid-structure interaction of a collapsible tube
The well known collapsible tube experiment was conducted to obtain flow, pressure and materials property data for steady state conditions. These were then used as the boundary conditions for a fully coupled fluid-structure interaction (FSI) model using a propriety computer code, LS-DYNA. The shape profiles for the tube were also recorded. In order to obtain similar collapse modes to the experiment, it was necessary to model the tube flat, and then inflate it into a circular profile, leaving residual stresses in the walls. The profile shape then agreed well with the experimental ones. Two departures from the physical properties were required to reduce computer time to an acceptable level. One of these was the lowering of the speed of sound by two orders of magnitude which, due to the low velocities involved, still left the mach number below 0.2. The other was to increase the thickness of the tube to prevent the numerical collapse of elements. A compensation for this was made by lowering the Young's modulus for the tube material. Overall the results are qualitatively good. They give an indication of the power of the current FSI algorithms and the need to combine experiment and computer models in order to maximise the information that can be extracted both in terms of quantity and quality
Sociology Back to the Publics
This article is a reading of the `new sociology' that is mainly identified with the works of C. Wright Mills and Alvin Gouldner. Its main argument is that during the past 40 years the new sociology gave back a public face to sociology. This distinguishes it from the `old sociology' that had not been able to free itself from `private' social values. It is argued that Mills' power elite and Gouldner's coming crisis theses provided the foundation for a common enterprise among many `new sociologists' to develop a critical and public sociology that would seek to shape what Mills called the `democratic society of publics'.`New sociologists' share a critique of modern societies, namely, that though most modern societies have formal democracies, a substantial democratic social structure of publics is often lacking, due to the erosion of the public sphere by private values
Lifetime distributions in the methods of non-equilibrium statistical operator and superstatistics
A family of non-equilibrium statistical operators is introduced which differ
by the system age distribution over which the quasi-equilibrium (relevant)
distribution is averaged. To describe the nonequilibrium states of a system we
introduce a new thermodynamic parameter - the lifetime of a system.
Superstatistics, introduced in works of Beck and Cohen [Physica A \textbf{322},
(2003), 267] as fluctuating quantities of intensive thermodynamical parameters,
are obtained from the statistical distribution of lifetime (random time to the
system degeneracy) considered as a thermodynamical parameter. It is suggested
to set the mixing distribution of the fluctuating parameter in the
superstatistics theory in the form of the piecewise continuous functions. The
distribution of lifetime in such systems has different form on the different
stages of evolution of the system. The account of the past stages of the
evolution of a system can have a substantial impact on the non-equilibrium
behaviour of the system in a present time moment.Comment: 18 page
Pervasive protein thermal stability variation during the cell cycle
Quantitative mass spectrometry has established proteome-wide regulation of protein abundance and post-translational modifications in various biological processes. Here, we used quantitative mass spectrometry to systematically analyze the thermal stability and solubility of proteins on a proteome-wide scale during the eukaryotic cell cycle. We demonstrate pervasive variation of these biophysical parameters with most changes occurring in mitosis and G1. Various cellular pathways and components vary in thermal stability, such as cell-cycle factors, polymerases, and chromatin remodelers. We demonstrate that protein thermal stability serves as a proxy for enzyme activity, DNA binding, and complex formation in situ. Strikingly, a large cohort of intrinsically disordered and mitotically phosphorylated proteins is stabilized and solubilized in mitosis, suggesting a fundamental remodeling of the biophysical environment of the mitotic cell. Our data represent a rich resource for cell, structural, and systems biologists interested in proteome regulation during biological transitions
Hard Photodisintegration of a Proton Pair
We present a study of high energy photodisintegration of proton-pairs through
the gamma + 3He -> p+p+n channel. Photon energies from 0.8 to 4.7 GeV were used
in kinematics corresponding to a proton pair with high relative momentum and a
neutron nearly at rest. The s-11 scaling of the cross section, as predicted by
the constituent counting rule for two nucleon photodisintegration, was observed
for the first time. The onset of the scaling is at a higher energy and the
cross section is significantly lower than for deuteron (pn pair)
photodisintegration. For photon energies below the scaling region, the scaled
cross section was found to present a strong energy-dependent structure not
observed in deuteron photodisintegration.Comment: 7 pages, 3 figures, for submission to Phys. Lett.
Theory of output coupling for trapped fermionic atoms
We develop a dynamic theory of output coupling, for fermionic atoms initially
confined in a magnetic trap. We consider an exactly soluble one-dimensional
model, with a spatially localized delta-type coupling between the atoms in the
trap and a continuum of free-particle external modes. Two important special
cases are considered for the confinement potential: the infinite box and the
harmonic oscillator. We establish that in both cases a bound state of the
coupled system appears for any value of the coupling constant, implying that
the trap population does not vanish in the infinite-time limit. For weak
coupling, the energy spectrum of the outgoing beam exhibits peaks corresponding
to the initially occupied energy levels in the trap; the height of these peaks
increases with the energy. As the coupling gets stronger, the energy spectrum
is displaced towards dressed energies of the fermions in the trap. The
corresponding dressed states result from the coupling between the unperturbed
fermionic states in the trap, mediated by the coupling between these states and
the continuum. In the strong-coupling limit, there is a reinforcement of the
lowest-energy dressed mode, which contributes to the energy spectrum of the
outgoing beam more strongly than the other modes. This effect is especially
pronounced for the one-dimensional box, which indicates that the efficiency of
the mode-reinforcement mechanism depends on the steepness of the confinement
potential. In this case, a quasi-monochromatic anti-bunched atomic beam is
obtained. Results for a bosonic sample are also shown for comparison.Comment: 16 pages, 7 figures, added discussion on time-dependent spectral
distribution and corresponding figur
Elastic electron deuteron scattering with consistent meson exchange and relativistic contributions of leading order
The influence of relativistic contributions to elastic electron deuteron
scattering is studied systematically at low and intermediate momentum transfers
( fm). In a -expansion, all leading order
relativistic -exchange contributions consistent with the Bonn OBEPQ models
are included. In addition, static heavy meson exchange currents including boost
terms and lowest order -currents are considered. Sizeable
effects from the various relativistic two-body contributions, mainly from
-exchange, have been found in form factors, structure functions and the
tensor polarization . Furthermore, static properties, viz. magnetic
dipole and charge quadrupole moments and the mean square charge radius are
evaluated.Comment: 15 pages Latex including 5 figures, final version accepted for
publication in Phys.Rev.C Details of changes: (i) The notation of the curves
in Figs. 1 and 2 have been clarified with respect to left and right panels.
(ii) In Figs. 3 and 4 an experimental point for T_20 has been added and a
corresponding reference [48] (iii) At the end of the text we have added a
paragraph concerning the quality of the Bonn OBEPQ potential
Codes of Fair Competition: The National Recovery Act, 1933-1935, and the Women’s Dress Manufacturing Industry
Controversial issues prevalent in today’s ready-to-wear apparel industry include the right of workers to join unions, the proliferation of sweatshops and sweatshop conditions, and design piracy. The idea of forming codes of conduct to establish criteria of ethical business practices is not new to the apparel industry. Indeed, the women’s dress manufacturing industry discussed and debated codes of fair competition under the New Deal Policies of the National Recovery Act (NRA) of 1933 to 1935. Primary sources for this study included governmental hearings in the establishment of the NRA Dress Code, The New York Times, Women’s Wear Daily, and the Journal of the Patent Office Society. The history of the NRA codes implemented in the U.S. women’s ready-to-wear apparel industry provides an important case study highlighting the difficulties and complexities of creating and achieving industry-wide standard practices through self-regulation. The failure of the NRA demonstrates that even with the joint cooperation of industry, labor, and consumer groups and the backing of the force of law, codes of fair competition proved impossible to enforce
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