3,620 research outputs found
Stress Transmission through Three-Dimensional Ordered Granular Arrays
We measure the local contact forces at both the top and bottom boundaries of
three-dimensional face-centered-cubic and hexagonal-close-packed granular
crystals in response to an external force applied to a small area at the top
surface. Depending on the crystal structure, we find markedly different results
which can be understood in terms of force balance considerations in the
specific geometry of the crystal. Small amounts of disorder are found to create
additional structure at both the top and bottom surfaces.Comment: 9 pages including 9 figures (many in color) submitted to PR
Medicos, poultice wallahs and comrades in service: masculinity and military medicine in Britain during the First World War
The subject of British military medicine during the First World War has long been a fruitful one for historians of gender. From the bodily inspection of recruits and conscripts through the expanding roles of women as medical care providers to the physical and emotional aftermath of conflict experienced by men suffering from war-related wounds and illness, the medical history of the war has shed important light on how the war shaped British masculinities and femininities as cultural, subjective and embodied identities. Much of this literature has, however, focused on the gendered identities of female nurses and sick and wounded servicemen. Increasingly, however, more complex understandings of the ways in which medical caregiving in wartime shaped the gender identities of male caregivers are starting to emerge. This article explores some of these emerging understandings of the masculinity of male medical caregivers, and their relationship to the wider literature around the complex and sometimes contradictory relationship between warfare and medicine. It examines the ways in which the masculine identity of male medical caregivers from the ranks of the Royal Army Medical Corps, namely stretcher bearers and medical orderlies, was perceived and represented both by the men themselves and those they cared for. In doing so it argues that total war played a crucial role in shaping social and cultural perceptions of caregiving as a gendered practice. It also identifies particular tensions between continuity and change in social understandings of medical care as a gendered practice which would continue to shape twentieth-century British society in the war’s aftermath
Search for the glueball candidates f0(1500) and fJ(1710) in gamma gamma collisions
Data taken with the ALEPH detector at LEP1 have been used to search for gamma
gamma production of the glueball candidates f0(1500) and fJ(1710) via their
decay to pi+pi-. No signal is observed and upper limits to the product of gamma
gamma width and pi+pi- branching ratio of the f0(1500) and the fJ(1710) have
been measured to be Gamma_(gamma gamma -> f0(1500)). BR(f0(1500)->pi+pi-) <
0.31 keV and Gamma_(gamma gamma -> fJ(1710)). BR(fJ(1710)->pi+pi-) < 0.55 keV
at 95% confidence level.Comment: 10 pages, 3 figure
The UV spectrum of HS1700+6416 II. FUSE observations of the HeII Lyman alpha forest
We present the far-UV spectrum of the quasar HS1700+6416 taken with FUSE.
This QSO provides the second line of sight with the HeII absorption resolved
into a Ly alpha forest structure. Since HS1700+6416 is slightly less redshifted
(z=2.72) than HE2347-4342, we only probe the post-reionization phase of HeII,
seen in the evolution of the HeII opacity, which is consistent with a simple
power law. The HeII/HI ratio eta is estimated using a line profile-fitting
procedure and an apparent optical depth approach, respectively. The expected
metal line absorption in the far-UV is taken into account as well as molecular
absorption of galactic H_2. About 27% of the eta values are affected by metal
line absorption. In order to investigate the applicability of the analysis
methods, we create simple artificial spectra based on the statistical
properties of the HI Ly alpha forest. The analysis of the artificial data
demonstrates that the apparent optical depth method as well as the line
profile-fitting procedure lead to confident results for restricted data samples
only (12.0 < log N(HI) < 13.0). The reasons are saturation in the case of the
apparent optical depth and thermal line widths in the case of the profile fits.
Furthermore, applying the methods to the unrestricted data set may mimic a
correlation between eta and the strength of the HI absorption. For the
restricted data samples a scatter of 10 - 15% in eta would be expected even if
the underlying value is constant. The observed scatter is significantly larger
than expected, indicating that the intergalactic radiation background is indeed
fluctuating. In the redshift range 2.58 < z < 2.72, where the data quality is
best, we find eta ~ 100, suggesting a contribution of soft sources like
galaxies to the UV background.Comment: 18 pages, 14 figures, accepted for publication in A&
Ernst Freund as Precursor of the Rational Study of Corporate Law
Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe
Search for CP Violation in the Decay Z -> b (b bar) g
About three million hadronic decays of the Z collected by ALEPH in the years
1991-1994 are used to search for anomalous CP violation beyond the Standard
Model in the decay Z -> b \bar{b} g. The study is performed by analyzing
angular correlations between the two quarks and the gluon in three-jet events
and by measuring the differential two-jet rate. No signal of CP violation is
found. For the combinations of anomalous CP violating couplings, and , limits of \hat{h}_b < 0.59h^{\ast}_{b} < 3.02$ are given at 95\% CL.Comment: 8 pages, 1 postscript figure, uses here.sty, epsfig.st
Search for supersymmetry with a dominant R-parity violating LQDbar couplings in e+e- collisions at centre-of-mass energies of 130GeV to 172 GeV
A search for pair-production of supersymmetric particles under the assumption
that R-parity is violated via a dominant LQDbar coupling has been performed
using the data collected by ALEPH at centre-of-mass energies of 130-172 GeV.
The observed candidate events in the data are in agreement with the Standard
Model expectation. This result is translated into lower limits on the masses of
charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, for
m_0=500 GeV/c^2 and tan(beta)=sqrt(2) charginos with masses smaller than 81
GeV/c^2 and neutralinos with masses smaller than 29 GeV/c^2 are excluded at the
95% confidence level for any generation structure of the LQDbar coupling.Comment: 32 pages, 30 figure
Epidemiology of Dengue Virus in Iquitos, Peru 1999 to 2005: Interepidemic and Epidemic Patterns of Transmission
To develop prevention (including vaccines) and control programs for dengue fever, a significant mosquito-borne disease in the tropics, there is an urgent need for comprehensive long term field epidemiological studies. We report results from a study that monitored ∼2,400 school children and some adult family members for dengue infection at 6 month intervals from 1999 to 2005, in the Amazonian city of Iquitos, Peru. At enrollment, ∼80% of the participants had a previous infection with DENV serotypes 1 and 2 or both. During the first 15 months, about 3 new infections for every 100 participants were observed among the study participants. In 2001, DENV-3, a serotype not previously observed in the region, invaded Iquitos in a process characterized by 3 distinct periods: amplification over at least a 5–6 month period, replacement of previously circulating serotypes, and epidemic transmission when incidence peaked. Incidence patterns of new infections were geographically distinct from baseline prevalence rates prior to arrival of DENV-3, but closely mirrored them during the invasion. DENV transmission varied geographically corresponding to elevated mosquito densities. The invasion of a novel serotype is often characterized by 5–6 months of silent transmission before traditional surveillance programs detect the virus. This article sets the stage for subsequent publications on dengue epidemiology
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