1,674 research outputs found
The halo mass function through the cosmic ages
In this paper we investigate how the halo mass function evolves with
redshift, based on a suite of very large (with N_p = 3072^3 - 6000^3 particles)
cosmological N-body simulations. Our halo catalogue data spans a redshift range
of z = 0-30, allowing us to probe the mass function from the dark ages to the
present. We utilise both the Friends-of-Friends (FOF) and Spherical Overdensity
(SO) halofinding methods to directly compare the mass function derived using
these commonly used halo definitions. The mass function from SO haloes exhibits
a clear evolution with redshift, especially during the recent era of dark
energy dominance (z < 1). We provide a redshift-parameterised fit for the SO
mass function valid for the entire redshift range to within ~20% as well as a
scheme to calculate the mass function for haloes with arbitrary overdensities.
The FOF mass function displays a weaker evolution with redshift. We provide a
`universal' fit for the FOF mass function, fitted to data across the entire
redshift range simultaneously, and observe redshift evolution in our data
versus this fit. The relative evolution of the mass functions derived via the
two methods is compared and we find that the mass functions most closely match
at z=0. The disparity at z=0 between the FOF and SO mass functions resides in
their high mass tails where the collapsed fraction of mass in SO haloes is ~80%
of that in FOF haloes. This difference grows with redshift so that, by z>20,
the SO algorithm finds a ~50-80% lower collapsed fraction in high mass haloes
than does the FOF algorithm, due in part to the significant over-linking
effects known to affect the FOF method.Comment: v4, 16 pages, 16 colour figures. Changed to match MNRAS print
version. NOTE: v1 of this paper has a typo in the fitting function. Please
ensure you use the latest versio
EC00-2540 Field Records for Restricted Use Pesticide Applications and Integrated Crop Management by Private Applicators
Private applicators must record their restricted use pesticide (RUP) applications, as required by the Food, Agriculture, Conservation and Trade (FACT) Act of 1990. The USDA Agricultural Marketing Service administers this activity. In Nebraska, RUP application records must be maintained for three years from the date of application. The certified pesticide applicator should retain these RUP records, but must be able to make them accessible for copying by authorized representatives. This booklet is a suggested guide for preliminary or final RUP application records
Casein kinase iδ mutations in familial migraine and advanced sleep phase.
Migraine is a common disabling disorder with a significant genetic component, characterized by severe headache and often accompanied by nausea, vomiting, and light sensitivity. We identified two families, each with a distinct missense mutation in the gene encoding casein kinase Iδ (CKIδ), in which the mutation cosegregated with both the presence of migraine and advanced sleep phase. The resulting alterations (T44A and H46R) occurred in the conserved catalytic domain of CKIδ, where they caused reduced enzyme activity. Mice engineered to carry the CKIδ-T44A allele were more sensitive to pain after treatment with the migraine trigger nitroglycerin. CKIδ-T44A mice also exhibited a reduced threshold for cortical spreading depression (believed to be the physiological analog of migraine aura) and greater arterial dilation during cortical spreading depression. Astrocytes from CKIδ-T44A mice showed increased spontaneous and evoked calcium signaling. These genetic, cellular, physiological, and behavioral analyses suggest that decreases in CKIδ activity can contribute to the pathogenesis of migraine
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Exposure to tricyclic antidepressants is associated with an increased risk of incident CHD events in a population-based study
Purpose
The purpose of this study was to assess the association between antidepressant use and incident coronary heart disease (CHD) events in a sample of individuals without known baseline heart disease.
Participants and methods
We studied a group of 970 randomly selected community-dwelling adults in the 1995 Nova Scotia Health Survey, who were followed for up to 10 years. Antidepressant usage was classified according to class. Primary outcomes were acute coronary syndrome hospitalizations or cardiac death, determined by centralized, standardized ratings.
Results
During a follow-up period of 10 years, there were 147 incident CHD events (139 acute coronary syndromes and 8 cardiac deaths) during the 8129 person-years of observation (incidence rate=18.1 events/1000 person-years). In a model controlling for age, sex, Framingham risk score, time to last annual exam, aspirin exposure, and depressive symptoms, an increased risk of CHD events was associated with tricyclic antidepressant exposure (adjusted hazard ratio, 2.10; 95% confidence interval, 1.09–4.06; p =0.027).
Conclusion
In this prospective population-based study, exposure to tricyclic antidepressants was associated with higher risk of first CHD events
Limiting Federal Agency Preemption: Recommendations for a New Federalism Executive Order
The structure of the U.S. Constitution reflects a profound respect for the principles of federalism and state sovereignty. These principles require the federal government to recognize and encourage opportunities for state and local governments to exercise their authority, especially in areas of traditional state concern such as the protection of the health, safety, and welfare of their citizens. However, over the last six years there has been a coordinated Executive Branch effortto use the regulatory process to shield certain product manufacturers from state tort liability. The Food and Drug Administration, National Highway Traffic Safety Administration, and Consumer Product Safety Commission, among others, have attempted to use the doctrine of preemption to block consumers’ access to state courts. During the Bush Administration, executive agencies have included assertions of preemption in regulatory preambles, filed amicus briefs in litigation in which other litigants have argued that federal statutes preempt state law, and submitted to Congress draft legislation that would preempt state and local authority to protect public health, safety, and the environment.
The Obama administration should replace Executive Order 13132, which instructs administrative agencies to consider the federalism implications of their actions, with an Executive Order that is more protective of the legitimate interests of state governments in maintaining their traditional role in protecting the health, safety and welfare of their citizens. While the current order has some desirable features, it is inadequate to prompt the type of deliberations in which agencies should engage when they are considering whether to support the preemption of state law
War Manifestos
This Article is the first to examine “war manifestos,” documents that set out the legal reasons sovereigns provided for going to war from the late fifteenth through the mid-twentieth centuries. We have assembled the world’s largest collection of war manifestos—over 350—in languages as diverse as Classical Chinese, German, French, Latin, Serbo-Croatian, and Dutch. Prior Anglophone scholarship has almost entirely missed war manifestos. This gap in the literature has produced a correspondingly large gap in our understanding of the role of war during the period in which manifestos were commonly used. Examining these previously ignored manifestos reveals that states exercised the right to wage war in ways that would be inconceivable today. In short, the right to intervene militarily could be asserted in any situation in which a legal right had been violated and all peaceful channels had been explored and exhausted. This Article begins by describing war manifestos. It then explores their history and evolution over the course of five centuries, explains the purposes they served for sovereigns, shows the many “just causes” they cited for war, and, finally, considers the lessons they hold for modern legal dilemmas. The discovery of war manifestos as a set of legal documents not only offers lawyers and legal scholars a new window into the international legal universe of the past, but it also casts new light on several long-standing legal debates
War Manifestos
This Article is the first to examine war manifestos, documents that set out the legal reasons sovereigns provided for going to war from the late fifteenth through the mid-twentieth centuries. We have assembled the world\u27s largest collection of war manifestos-over 350-in languages as diverse as Classical Chinese, German, French, Latin, Serbo-Croatian, and Dutch. Prior Anglophone scholarship has almost entirely missed war manifestos. This gap in the literature has produced a correspondingly large gap in our understanding of the role of war during the period in which manifestos were commonly used. Examining these previously ignored manifestos reveals that states exercised the right to wage war in ways that would be inconceivable today. In short, the right to intervene militarily could be asserted in any situation in which a legal right had been violated and all peaceful channels had been explored and exhausted. This Article begins by describing war manifestos. It then explores their history and evolution over the course of five centuries, explains the purposes they served for sovereigns, shows the many \u27just causes they cited for war, and, finally, considers the lessons they hold for modern legal dilemmas. The discovery of war manifestos as a set of legal documents not only offers lawyers and legal scholars a new window into the international legal universe of the past, but it also casts new light on several long-standing legal debates
Remote Sensing of Chiral Signatures on Mars
We describe circular polarization as a remote sensing diagnostic of chiral
signatures which may be applied to Mars. The remarkable phenomenon of
homochirality provides a unique biosignature which can be amenable to remote
sensing through circular polarization spectroscopy. The natural tendency of
microbes to congregate in close knit communities would be beneficial for such a
survey. Observations of selected areas of the Mars surface could reveal chiral
signatures and hence explore the possibility of extant or preserved biological
material. We describe a new instrumental technique that may enable observations
of this form.Comment: 14 pages, 3 figures; to be published in Planetary and Space Scienc
Differential electron yield imaging with STXM
Total electron yield (TEY) imaging is an established scanning transmission
X-ray microscopy (STXM) technique that gives varying contrast based on a
sample's geometry, elemental composition, and electrical conductivity. However,
the TEY-STXM signal is determined solely by the electrons that the beam ejects
from the sample. A related technique, X-ray beam-induced current (XBIC)
imaging, is sensitive to electrons and holes independently, but requires
electric fields in the sample. Here we report that multi-electrode devices can
be wired to produce differential electron yield (DEY) contrast, which is also
independently sensitive to electrons and holes, but does not require an
electric field. Depending on whether the region illuminated by the focused STXM
beam is better connected to one electrode or another, the DEY-STXM contrast
changes sign. DEY-STXM images thus provide a vivid map of a device's
connectivity landscape, which can be key to understanding device function and
failure. To demonstrate an application in the area of failure analysis, we
image a 100~nm, lithographically-defined aluminum nanowire that has failed
after being stressed with a large current density.Comment: 8 pages, 6 figure
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