4,047 research outputs found
The Distribution and Prevalence of the Alfalfa Blotch Leafminer (Diptera: Agromyzidae) in Illinois
Surveys were made in 2001 and 2002 to determine the distribution and prevalence of the alfalfa blotch leafminer, Agromyza frontella (Diptera: Agromyzidae), and its primary parasitoids, Dacnusa dryas and Chrysocharis liriomyzae (Hymenoptera: Braconidae and Eulophidae, respectively), in Illinois. We collected 239 samples from alfalfa fields in the alfalfa-producing regions of Illinois. Samples from each site consisted of 20 cut stems and 10 sets of 10 sweeps in 2001, and 40 stems and 10 sets of 20 sweeps in 2002. Each trifoliate was examined for mining and pinholing injury, and the number of adult A. frontella, D. dryas, and C. liriomyzae per 10 sweeps was calculated for each site. We found that 16.3% of the sites were infested with A. frontella, and all infested fields were north of 39.95 N latitude. Although up to 95% of stems were injured at some sites, mean injury per stem never exceeded 12% of trifoliates. Maximum adult abundance was 8.1 adults per 10 sweeps. We did not detect D. dryas or C. liriomyzae in any of the sweep samples. Because of consistently low populations and the relatively slow rate of A. frontella’s spread in Illinois, we conclude that A. frontella is not a serious threat to alfalfa production in this state at this time
Projected Red Pine Yields from Aldrin-Treated and Untreated Stands Damaged by White Grub (Coleoptera: Scarabaeidae) and Other Agents at Stand Age Ten Years
White grubs affect pine plantations by killing some trees and by reducing vigor and growth of others. Light to moderate mortality only slightly affects timber yields and financial re- turns if the level of trees remains at the number required for full utilization of the site. Reduced height growth, however, lowers apparent site quality and substantially affects yields and financial returns. The 100 year projections suggest that greater product volumes, financial returns. and higher interest rates on the investment will be gained by grub control before tree growth is reduced
Dacharry, Monique. Tourisme et transport en Méditerranée occidentale. Îles Baléares – Corse – Sardaigne. Paris, Presses Universitaires de France, 1964, 146 pages and bibliography.
On correlation between protein secondary structure, backbone bond angles, and side-chain orientations
We investigate the fine structure of the sp3 hybridized covalent bond
geometry that governs the tetrahedral architecture around the central
C carbon of a protein backbone, and for this we develop new
visualization techniques to analyze high resolution X-ray structures in Protein
Data Bank. We observe that there is a correlation between the deformations of
the ideal tetrahedral symmetry and the local secondary structure of the
protein. We propose a universal coarse grained energy function to describe the
ensuing side-chain geometry in terms of the C carbon orientations. The
energy function can model the side-chain geometry with a sub-atomic precision.
As an example we construct the C-C structure of HP35 chicken
villin headpiece. We obtain a configuration that deviates less than 0.4 \.A in
root-mean-square distance from the experimental X-ray structure
IMPROVING PROJECT MANAGEMENT FOR SUSTAINABLE DEVELOPMENT
Institutional and Behavioral Economics,
Dynamic Normalization for Compact Binary Coalescence Searches in Non-Stationary Noise
The output of gravitational-wave interferometers, such as LIGO and Virgo, can be highly non-stationary. Broadband detector noise can affect the detector sensitivity on the order of tens of seconds. Gravitational-wave transient searches, such as those for colliding black holes, estimate this noise in order to identify gravitational-wave events. During times of non-stationarity we see a higher rate of false events being reported. To accurately separate signal from noise, it is imperative to incorporate the changing detector state into gravitational-wave searches. We develop a new statistic which estimates the variation of the interferometric detector noise. We use this statistic to re-rank candidate events identified during LIGO-Virgo's second observing run by the PyCBC search pipeline. This results in a 7% improvement in the sensitivity volume for low mass binaries, particularly binary neutron stars mergers
Improving the Sensitivity of Advanced LIGO Using Noise Subtraction
This paper presents an adaptable, parallelizable method for subtracting
linearly coupled noise from Advanced LIGO data. We explain the features
developed to ensure that the process is robust enough to handle the variability
present in Advanced LIGO data. In this work, we target subtraction of noise due
to beam jitter, detector calibration lines, and mains power lines. We
demonstrate noise subtraction over the entirety of the second observing run,
resulting in increases in sensitivity comparable to those reported in previous
targeted efforts. Over the course of the second observing run, we see a 30%
increase in Advanced LIGO sensitivity to gravitational waves from a broad range
of compact binary systems. We expect the use of this method to result in a
higher rate of detected gravitational-wave signals in Advanced LIGO data.Comment: 15 pages, 6 figure
Memory and rejuvenation in a spin glass
The temperature dependence of the magnetisation of a Cu(Mn) spin glass (
57 K) has been investigated using weak probing magnetic fields ( =
0.5 or 0 Oe) and specific thermal protocols. The behaviour of the zero-field
cooled, thermoremanent and isothermal remanent magnetisation on (re-)cooling
the system from a temperature (40 K) where the system has been aged is
investigated. It is observed that the measured magnetisation is formed by two
parts: (i) a temperature- and observation time-dependent thermally activated
relaxational part governed by the age- and temperature-dependent response
function and the (latest) field change made at a lower temperature, superposed
on (ii) a weakly temperature-dependent frozen-in part. Interestingly we observe
that the spin configuration that is imprinted during an elongated halt in the
cooling, if it is accompanied by a field induced magnetisation, also includes a
unidirectional excess magnetisation that is recovered on returning to the
ageing temperature.Comment: EPL style; 7 pages, 5 figure
Elastic Energy and Phase Structure in a Continuous Spin Ising Chain with Applications to the Protein Folding Problem
We present a numerical Monte Carlo analysis of a continuos spin Ising chain
that can describe the statistical proterties of folded proteins. We find that
depending on the value of the Metropolis temperature, the model displays the
three known nontrivial phases of polymers: At low temperatures the model is in
a collapsed phase, at medium temperatures it is in a random walk phase, and at
high temperatures it enters the self-avoiding random walk phase. By
investigating the temperature dependence of the specific energy we confirm that
the transition between the collapsed phase and the random walk phase is a phase
transition, while the random walk phase and self-avoiding random walk phase are
separated from each other by a cross-over transition. We also compare the
predictions of the model to a phenomenological elastic energy formula, proposed
by Huang and Lei to describe folded proteins.Comment: 12 pages, 23 figures, RevTeX 4.
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