6,885 research outputs found
Adult Female Spruce Bedworm, \u3ci\u3eChoristoneura Fumiferana\u3c/i\u3e (Lepidoptera: Tortricidae), Dry Weight in Relationship to Pupal Fresh Weight and Case Diameter
(excerpt)
The weights of adult insects are often measured in production and population studies in order to estimate such variables as growth rates, food conversion efficiencies, fecundity, and others. For the eastern spruce budworm, Choristoneura fumiferana (Clemens), both pupal fresh weights and pupal case diameters have been measured as indicators of adult fecundity and adult dry weights (Miller 1957). However, there are no reports explicitly showing the relationship between these metric pupal variables and adult dry weights. This is the goal of this note
Undergraduate Library Internships at Musselman Library, Gettysburg College
In 2015-2016, Musselman Library at Gettysburg College participated in Cohort 3 of the Association of College and Research Librariesâ Assessment in Action program. This report outlines an assessment completed of former undergraduate library interns in order to explore the impact their internship experience had on the development of career goals, acceptance to and preparation for graduate education, and their early career. Through an online survey (n= 45) and six semi-structured telephone interviews, respondents reported a positive impact on the above areas
Earth-like sand fluxes on Mars
Strong and sustained winds on Mars have been considered rare, on the basis of surface meteorology measurements and global circulation models, raising the question of whether the abundant dunes and evidence for wind erosion seen on the planet are a current process. Recent studies showed sand activity, but could not determine whether entire dunes were movingâimplying large sand fluxesâor whether more localized and surficial changes had occurred. Here we present measurements of the migration rate of sand ripples and dune lee fronts at the Nili Patera dune field. We show that the dunes are near steady state, with their entire volumes composed of mobile sand. The dunes have unexpectedly high sand fluxes, similar, for example, to those in Victoria Valley, Antarctica, implying that rates of landscape modification on Mars and Earth are similar
Debris cover and surface melt at a temperate maritime alpine glacier: Franz Josef Glacier, New Zealand
Melt rates on glaciers are strongly influenced by the presence of supraglacial debris, which can either enhance or reduce ablation relative to bare ice. Most recently, Franz Josef Glacier has entered into a phase of strong retreat and downwasting, with the increasing emergence of debris on the surface in the ablation zone. Previously at Franz Josef Glacier, melt has only been measured on bare ice. During February 2012, a network of 11 ablation stakes was drilled into locations of varying supraglacial debris thickness on the lower glacier. Mean ablation rates over 9 days varied over the range 1.2â10.1 cm dâ1, and were closely related to debris thickness. Concomitant observations of air temperature allowed the application of a degree-day approach to the calculation of melt rates, with air temperature providing a strong indicator of melt. Degree-day factors (d f) varied over the range 1.1â8.1 mm dâ1 °Câ1 (mean of 4.4 mm dâ1 °Câ1), comparable with rates reported in other studies. Mapping of the current debris cover revealed 0.7 km2 of the 4.9 km2 ablation zone surface was debris-covered, with thicknesses ranging 1â50 cm. Based on measured debris thicknesses and d f, ablation on debris-covered areas of the glacier is reduced by a total of 41% which equates to a 6% reduction in melt overall across the entire ablation zone. This study highlights the usefulness of a short-term survey to gather representative ablation data, consistent with numerous overseas ablation studies on debris-covered glaciers
Investigating the Role of Real Divisia Money in Persistence-Robust Econometric Models
This paper investigates the causal relationships between real money and real activity. Whereas previous literature has mainly focused on simple-sum aggregates, we instead use Divisia ones, thus avoiding the so-called Barnett Critique. Standard Granger non-causality tests are implemented in two di€erent frameworks: Fully Modied VARs (Phillips, 1995) and surplus-lag VARX models (Bauer and Maynard, 2012). These two environments allow modeling mixtures of I(0)/I(1) variables with possible cointegration without pretesting for ntegration nor for the dimension of the cointegration space. Moreover the latter method is also robust to various other forms of persistence such as local-to-unity processes, long memory/fractional integration, or unmodeled breaks-in-mean in the causal variables. By implementing the tests on di€erent sub-samples identied by standard structural break tests, and using three di€erent measures of money (DM4, DM4- and DM3), the tests suggest a unidirectional causality from activity to money. Moreover, from one period to another, the whole causal structure of the systems seem to change, as well as the stationarity of the series. At last, the two methodologies return similar results
Possible X-ray diagnostic for jet/disk dominance in Type 1 AGN
Using Rossi X-ray Timing Explorer Seyfert 1 and 1.2 data spanning 9 years, we
study correlations between X-ray spectral features. The sample consists of 350
time-resolved spectra from 12 Seyfert 1 and 1.2 galaxies. Each spectrum is
fitted to a model with an intrinsic powerlaw X-ray spectrum produced close to
the central black hole that is reprocessed and absorbed by material around the
black hole. To test the robustness of our results, we performed Monte Carlo
simulations of the spectral sample. We find a complex relationship between the
iron line equivalent width (EW) and the underlying power law index (Gamma). The
data reveal a correlation between Gamma and EW which turns over at Gamma <~ 2,
but finds a weak anti-correlation for steeper photon indices. We propose that
this relationship is driven by dilution of a disk spectrum (which includes the
narrow iron line) by a beamed jet component and, hence, could be used as a
diagnostic of jet-dominance. In addition, our sample shows a strong correlation
between the reflection fraction (R) and Gamma, but we find that it is likely
the result of modeling degeneracies. We also see the X-ray Baldwin effect (an
anti-correlation between the 2-10 keV X-ray luminosity and EW) for the sample
as a whole, but not for the individual galaxies and galaxy types.Comment: Accepted for publication in ApJ, 14 page
Atypical hemolytic uremic syndrome in the postpartum period: a case series
Background: Atypical hemolytic uremic syndrome (aHUS) may present in either the antepartum or postpartum period and is often indistinguishable from other pregnancy-associated diseases. Timely recognition and appropriate treatment can greatly reduce maternal morbidity and mortality.
Cases: This case series describes two cases of aHUS in the post-partum period, the difficulty in distinguishing the diagnosis, and the implementation of appropriate treatment with eculizumab, a terminal complement inhibitor.
Conclusion: As a terminal complement inhibitor, eculizumab, has been shown to significantly improve clinical and long term renal outcomes, early diagnosis of aHUS is increasingly important. These two cases of aHUS demonstrate the path of accurate diagnosis and timely initiation of therapy to maximize the possibility of patient recovery
Exploring Behavior Discovery Methods for Heterogeneous Swarms of Limited-Capability Robots
We study the problem of determining the emergent behaviors that are possible
given a functionally heterogeneous swarm of robots with limited capabilities.
Prior work has considered behavior search for homogeneous swarms and proposed
the use of novelty search over either a hand-specified or learned behavior
space followed by clustering to return a taxonomy of emergent behaviors to the
user. In this paper, we seek to better understand the role of novelty search
and the efficacy of using clustering to discover novel emergent behaviors.
Through a large set of experiments and ablations, we analyze the effect of
representations, evolutionary search, and various clustering methods in the
search for novel behaviors in a heterogeneous swarm. Our results indicate that
prior methods fail to discover many interesting behaviors and that an iterative
human-in-the-loop discovery process discovers more behaviors than random
search, swarm chemistry, and automated behavior discovery. The combined
discoveries of our experiments uncover 23 emergent behaviors, 18 of which are
novel discoveries. To the best of our knowledge, these are the first known
emergent behaviors for heterogeneous swarms of computation-free agents. Videos,
code, and appendix are available at the project website:
https://sites.google.com/view/heterogeneous-bd-methodsComment: 11 pages, 9 figures, To be published in Proceedings IEEE
International Symposium on Multi-Robot & Multi-Agent Systems (MRS 2023
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