2,914 research outputs found
A new view of the Lindemann criterion
The Lindemann criterion is reformulated in terms of the average shear modulus
of the melting crystal, indicating a critical melting shear strain which
is necessary to form the many different inherent states of the liquid. In glass
formers with covalent bonds, one has to distinguish between soft and hard
degrees of freedom to reach agreement. The temperature dependence of the
picosecond mean square displacements of liquid and crystal shows that there are
two separate contributions to the divergence of the viscosity with decreasing
temperature: the anharmonic increase of the shear modulus and a diverging
correlation length .Comment: 4 pages, 3 figure
Innocent Spouses, Reasonable Women and Divorce: The Gap Between Reality and the Internal Revenue Code
This Article asks whether the reasonable woman should become the standard for women seeking relief from tax liabilities under the innocent spouse provision of the I.R.C. and whether an even more specific standard should be adopted for women who are also going through divorce or are in similar situations
Innocent Spouses, Reasonable Women and Divorce: The Gap Between Reality and the Internal Revenue Code
This Article asks whether the reasonable woman should become the standard for women seeking relief from tax liabilities under the innocent spouse provision of the I.R.C. and whether an even more specific standard should be adopted for women who are also going through divorce or are in similar situations
Ecology of antimicrobial resistance: humans, animals, food and environment
Antimicrobial resistance is a major health problem. After decades of research, numerous difficulties in tackling resistance have emerged, from the paucity of new antimicrobials to the inefficient contingency plans to reduce the use of antimicrobials; consequently, resistance to these drugs is out of control. Today we know that bacteria from the environment are often at the very origin of the acquired resistance determinants found in hospitals worldwide. Here we define the genetic components that flow from the environment to pathogenic bacteria and thereby confer a quantum increase in resistance levels, as resistance units (RU). Environmental bacteria as well as microbiomes from humans, animals, and food represent an infinite reservoir of RU, which are based on genes that have had, or not, a resistance function in their original bacterial hosts. This brief review presents our current knowledge of antimicrobial resistance and its consequences, with special focus on the importance of an ecologic perspective of antimicrobial resistance. This discipline encompasses the study of the relationships of entities and events in the framework of curing and preventing disease, a definition that takes into account both microbial ecology and antimicrobial resistance. Understanding the flux of RU throughout the diverse ecosystems is crucial to assess, prevent and eventually predict emerging scaffolds before they colonize health institutions. Collaborative horizontal research scenarios should be envisaged and involve all actors working with humans, animals, food and the environment
Ecology of antimicrobial resistance: humans, animals, food and environment
Antimicrobial resistance is a major health problem. After decades of research, numerous difficulties in tacklingresistance have emerged, from the paucity of new antimicrobials to the inefficient contingency plans to reduce the use ofantimicrobials; consequently, resistance to these drugs is out of control. Today we know that bacteria from the environmentare often at the very origin of the acquired resistance determinants found in hospitals worldwide. Here we define the geneticcomponents that flow from the environment to pathogenic bacteria and thereby confer a quantum increase in resistance levels,as resistance units (RU). Environmental bacteria as well as microbiomes from humans, animals, and food represent aninfinite reservoir of RU, which are based on genes that have had, or not, a resistance function in their original bacterial hosts.This brief review presents our current knowledge of antimicrobial resistance and its consequences, with special focus on theimportance of an ecologic perspective of antimicrobial resistance. This discipline encompasses the study of the relationshipsof entities and events in the framework of curing and preventing disease, a definition that takes into account both microbialecology and antimicrobial resistance. Understanding the flux of RU throughout the diverse ecosystems is crucial to assess,prevent and eventually predict emerging scaffolds before they colonize health institutions. Collaborative horizontal researchscenarios should be envisaged and involve all actors working with humans, animals, food and the environment. [IntMicrobiol 2012; 15(3):101-109
Mergers and Beliefs
We study the combined effects of managerial optimism and market overvaluation on merger premiums and the chosen form of payment. Our empirical results are consistent with market overvaluation and the target manager‘s optimism as having the most influence on mergers. The observed form of payment corresponds to the acquiring manager‘s preferences, suggesting that the acquiring manager dictates the method of payment. Lastly, our model demonstrates why cash mergers are more likely to be hostile, and provides an explanation for why a combination of cash plus stock may be optimal
TARGET: A Digitizing And Trigger ASIC For The Cherenkov Telescope Array
The future ground-based gamma-ray observatory Cherenkov Telescope Array (CTA)
will feature multiple types of imaging atmospheric Cherenkov telescopes, each
with thousands of pixels. To be affordable, camera concepts for these
telescopes have to feature low cost per channel and at the same time meet the
requirements for CTA in order to achieve the desired scientific goals. We
present the concept of the TeV Array Readout Electronics with GSa/s sampling
and Event Trigger (TARGET) Application Specific Circuit (ASIC), envisaged to be
used in the cameras of various CTA telescopes, e.g. the Gamma-ray Cherenkov
Telescope (GCT), a proposed 2-Mirror Small-Sized Telescope, and the
Schwarzschild-Couder Telescope (SCT), a proposed Medium-Sized Telescope. In the
latest version of this readout concept the sampling and trigger parts are split
into dedicated ASICs, TARGET C and T5TEA, both providing 16 parallel input
channels. TARGET C features a tunable sampling rate (usually 1 GSa/s), a 16k
sample deep buffer for each channel and on-demand digitization and transmission
of waveforms with typical spans of ~100 ns. The trigger ASIC, T5TEA, provides 4
low voltage differential signal (LVDS) trigger outputs and can generate a
pedestal voltage independently for each channel. Trigger signals are generated
by T5TEA based on the analog sum of the input in four independent groups of
four adjacent channels and compared to a threshold set by the user. Thus, T5TEA
generates four LVDS trigger outputs, as well as 16 pedestal voltages fed to
TARGET C independently for each channel. We show preliminary results of the
characterization and testing of TARGET C and T5TEA.Comment: 6 pages, 8 figures, Proceedings of the 6th International Symposium on
High-Energy Gamma-Ray Astronomy (Gamma2016
Testing the neutrality of matter by acoustic means in a spherical resonator
New measurements to test the neutrality of matter by acoustic means are
reported. The apparatus is based on a spherical capacitor filled with gaseous
SF excited by an oscillating electric field. The apparatus has been
calibrated measuring the electric polarizability. Assuming charge conservation
in the decay of the neutron, the experiment gives a limit of
for the electron-proton charge
difference, the same limit holding for the charge of the neutron. Previous
measurements are critically reviewed and found incorrect: the present result is
the best limit obtained with this technique
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