1,668 research outputs found
Emittance growth mechanisms in the Tevatron beams
In this article we present results of emittance growth measurements in the
Tevatron beams. Several mechanisms leading to transverse and longitudinal
diffusions are analyzed and their contributions estimated.Comment: 7 p
Review of recent Tevatron operations
Fermilab's Tevatron proton-antiproton collider continues to improve its luminosity performance at the energy frontier {radical}s = 1.96 TeV. The recent Tevatron operation will be reviewed and notable tasks leading to advancements will be highlighted. The topics to be covered include: work performed during the 14-week shutdown in 2006, improved helical orbits, automatic orbit stabilization during high-energy physics (HEP) stores, optics corrections, improvements in the quench protection system, and avenues to maximizing the integrated luminosity delivered to the CDF and D0 experiments
Greenhouse gas emissions from an irrigated crop rotation utilizing dairy manure
Information on greenhouse gas (GHG) emissions from manure application in cropping systems of the irrigated mountain west region is needed. The effects of manure application rate and timing on GHG emissions from a four-year commercial rotation under sprinkler irrigation was investigated. Treatments included dry manure rates of 52 or 18 Mg/ha applied annually or 36 Mg/ha applied biennially as well as fertilizer and control treatments. Cumulative losses of N2O-N over the rotation ranged from 1.4 to 8.4 kg/ha with the 52 Mg/ha manure application losing the greatest amount of N2O-N. Calculated emission factors indicated that 0.13 to 0.24% of total N applied was lost as N2O-N, much less than the emission factor of 1% used by the IPCC. Cumulative CO2-C losses were greater in the manure treatments compared to the fertilizer and controls, with approximately 7% of carbon added lost as CO2-C. These soils acted as a sink for CH4-C with average fluxes ranging from -0.1 to -0.3 kg/ha. Maximum N2O-N flux levels occurred at soil moisture contents ranging from 0.3 to 0.4 m3/m3 and temperature near 25 °C, while CO2-C emissions occurred over broader soil moisture and temperature conditions. The overall global warming potential (GWP) associated with manure application indicated that the manure treatments had a net negative GWP while fertilizer treatment was near neutral. A better understanding of regional soil and climatic conditions that affect GHG emissions will enable the development of emission factors more appropriate for use in GHG inventory efforts
Correlates of Alcohol-Related Treatment Among American Indians and Alaska Natives with Lifetime Alcohol Use Disorder
Background: To describe sociodemographic and selected psychiatric disorder patterns and estimate correlates of seeking alcohol treatment among American Indians and Alaska Natives (AIAN) and non-Hispanic Whites (NHW) with lifetime alcohol use disorder (AUD). Methods: Data come from the 2012 to 2013 U.S. National Epidemiologic Survey on Alcohol and Related Conditions-III. We retrospectively identified participants who completed information on lifetime AUD, race/ethnicity, and seeking alcohol treatment or help for AUD. We used a generalized linear model with a log link and Poisson distribution to estimate prevalence ratios (PRs) among adults with DSM-5 lifetime AUD. We included the following correlates: race/ethnicity, sex, age, personal annual income, marital status, education, urban/rural status, U.S. region, any illegal drug use disorder, nicotine use disorder, and select mood-, anxiety-, personality-, and trauma-related disorders. Results: Among AIAN, the prevalence of lifetime AUD was 46.6%. Among AIAN with lifetime AUD, 33.8% sought alcohol-related treatment. Among individuals with lifetime AUD, AIAN were associated with greater alcohol-related treatment-seeking compared to NHW (adjusted PR = 1.41 [95% CI 1.26 to 1.58]). Among AIAN with AUD, being male and age 35 to 64 were statistically significant correlates of seeking treatment or help for AUD. Conclusions: A relatively higher proportion of AIAN than NHW with AUDs sought alcohol treatment. Among individuals with lifetime AUD, significant demographic and psychiatric disorder correlates of treatment are present, showing that certain groups are less likely to seek treatment or help for alcohol-related issues. Among AIAN with AUD, these correlates may reflect distinct patterns of seeking alcohol-related treatment, which can inform more effective treatment promotion efforts with this population
Strong lens search in the ESO public Survey KiDS
We have started a systematic search of strong lens candidates in the ESO
public survey KiDS based on the visual inspection of massive galaxies in the
redshift range . As a pilot program we have inspected 100 sq. deg.,
which overlap with SDSS and where there are known lenses to use as a control
sample. Taking advantage of the superb image quality of VST/OmegaCAM, the
colour information and accurate model subtracted images, we have found 18 new
lens candidates, for which spectroscopic confirmation will be needed to confirm
their lensing nature and study the mass profile of the lensing galaxies.Comment: 4 pages, 1 figure, to appear on the refereed Proceeding of the "The
Universe of Digital Sky Surveys" conference held at the INAF--OAC, Naples, on
25th-28th november 2014, to be published on Astrophysics and Space Science
Proceedings, edited by Longo, Napolitano, Marconi, Paolillo, Iodic
A new approach to perturbation theory for a Dirac particle in a central field
The explicit semiclassical treatment of logarithmic perturbation theory for
the bound-state problem within the framework of the Dirac equation is
developed. Avoiding disadvantages of the standard approach in the description
of exited states, new handy recursion formulae with the same simple form both
for ground and exited states have been obtained. As an example, the
perturbation expansions for the energy eigenvalues for the Yukawa potential
containing the vector part as well as the scalar component are considered.Comment: 12 pages, LaTe
MNK1 and MNK2 mediate adverse effects of high-fat feeding in distinct ways
The MAP kinase-interacting kinases (MNK1 and MNK2) are non-essential enzymes which are activated by MAP kinases. They are implicated in controlling protein synthesis. Here we show that mice in which the expression of either MNK1 or MNK2 has been knocked out (KO) are protected against adverse effects of high-fat feeding, and in distinct ways. High-fat diet (HFD)-fed MNK2-KO show less weight gain than wild-type animals, and improved glucose tolerance, better insulin sensitivity and markedly diminished adipose tissue inflammation. This suggests MNK2 plays a role in adipogenesis and/or lipogenesis and in macrophage biology. MNK1-KO/HFD mice show better glucose tolerance and insulin sensitivity, but gain weight and show similar adipose inflammation to WT animals. These data suggest MNK1 participates in mediating HFD-induced insulin resistance. Our findings reveal distinct roles for the MNKs in a novel area of disease biology, metabolic dysfunction, and suggests they are potential new targets for managing metabolic disease
Occurrence and abundance of antibiotic resistance genes in agricultural soil receiving dairy manure
Animal manures are commonly used to enhance soil fertility, but there are growing concerns over the impact of this practice on the development and dissemination of antibiotic resistance. The aim of this study was to determine the effect of annual dairy manure applications on the occurrence and abundance of antibiotic resistance genes (ARGs) in an agricultural soil under crop production. The experimental design was a randomized complete block with four replications, which included the following treatments: i) control (no fertilizer); ii) inorganic fertilizer; and iii) stockpiled dairy manure. Inorganic fertilizer was applied in the spring, while dairy manure was applied in the fall of 2012–2015 at 17.2, 34.5, and 52.0 Mg (dry wt.)/ha. Soil samples were collected in the spring (pre-plant) and fall (post-harvest) to a depth of 120 cm. DNA extracted from the soils was used in a quantitative real-time PCR reaction to determine absolute abundances (per g dry soil) and relative abundances (per 16S rRNA gene copies) of ARGs. The ARGs targeted were blaCTX-M-1, erm(B), sul1, tet(A), tet(W), and tet(X) and a class 1 integron-integrase gene (intI1), but only sul1, tet(W), tet(X), and intI1 were detected in enough samples to run statistics and draw conclusions. This study found that: i) manure application increases ARG abundances above background soil levels; ii) the higher the manure application rate, the higher the ARG abundance in soil; iii) the amount of manure applied is more important than reoccurring annual applications of the same amount of manure; iv) absolute abundance and occurrence of ARGs decreases with increasing soil depth, but relative abundances remained constant; and v) ARGs correlated with each other and a number of soil chemical parameters, but not with soil moisture or 16S rRNA gene. Overall, this study demonstrated that dairy manure applications significantly increase the abundance of clinically relevant ARGs when compared to soil that received inorganic fertilizer or no fertilizer/manure
Simple choreographies of the planar Newtonian -body Problem
In the -body problem, a simple choreography is a periodic solution, where
all masses chase each other on a single loop. In this paper we prove that for
the planar Newtonian -body problem with equal masses, , there are
at least different main simple choreographies. This
confirms a conjecture given by Chenciner and etc. in \cite{CGMS02}.Comment: 31pages, 6 figures. Refinements in notations and proof
Multidimensional continued fractions, dynamical renormalization and KAM theory
The disadvantage of `traditional' multidimensional continued fraction
algorithms is that it is not known whether they provide simultaneous rational
approximations for generic vectors. Following ideas of Dani, Lagarias and
Kleinbock-Margulis we describe a simple algorithm based on the dynamics of
flows on the homogeneous space SL(2,Z)\SL(2,R) (the space of lattices of
covolume one) that indeed yields best possible approximations to any irrational
vector. The algorithm is ideally suited for a number of dynamical applications
that involve small divisor problems. We explicitely construct renormalization
schemes for (a) the linearization of vector fields on tori of arbitrary
dimension and (b) the construction of invariant tori for Hamiltonian systems.Comment: 51 page
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