4,805 research outputs found
A New Species of Mnioes (Hymenoptera: Ichneumonidae) from the United States
This is the first record of the genus Mnioes in the United States. Previously described species are all Neotropic. Townes described the genus in 1946, placing Lampronota? jircunda Cresson, 1874, and Meniscus ? orbitalis Cresson, 1874, in it. The new species described here has been collected from several areas in the United States. This study was made while the author was a graduate student at The University of Michigan, Ann Arbor, Michigan
Fast-field cycling NMR is sensitive to the method of cross-linking in BSA gels
This work was supported by ARUK (grant number 19689).Non peer reviewedPublisher PD
Daily Eclosion Pattern of the Saratoga Spittlebug, Aphrophora Saratogensis (Fitch) (Homoptera: Cercopidae)
The Saratoga spittlebug, Aphrophora saratogensis (Fitch), is a destructive pest of young planted pines in the Lake States. The adults injure the pines by feeding on the sap of branches. However, nymphs feed on the sap of alternate host plants, which include many herbs and woody plants on the forest floor. Our studies show that the time of the eclosion and shortly thereafter is one of the most vulnerable periods in the insect\u27s life cycle. During this period the nymphs must free themselves from the eggs that are on pine buds, vacate the pines, search out suitable host plants on the forest floor, initiate feeding, and cover themselves with masses of spittle. And they must do this before they desiccate (Ewan, 1961), starve, or are captured by predators.
As part of a survival study we wanted to observe the nymphs at eclosion because their emergence and behavior pattern at that time would certainly affect their survival. In the Lake States area eclosion occurs from early April to late May, a period when weather varies greatly from cool and wet to warm and dry. Reported is the nymphal eclosion pattern during the peak of the eclosion periods in 1969 and 1970
MOCCA College: An assessment of inferential narrative and expository comprehension
[ES] MOCCA-C is an assessment of adult reading ability designed for early diagnosis of reading problems, for formative assessment in reading intervention planning, for assessment of reading improvement over time, and for assessment of reading intervention outcomes. It uses both narrative and expository reading passages and it currently has four forms. Two goals of this research were to compare narrative and expository passages on (a) their difficulty and (b) their ability to discriminate between good and poor readers. An additional goal was to assess whether narrative and expository passages measure the same or different comprehension dimensions. A final goal was to assess the reliability of forms. We randomly assigned students to forms with between 274 â 279 college students per form. Across the several forms, results suggest that narrative passages are easier and better discriminate between good and poor readers. However, both narrative and expository passages measure a single dimension of ability. MOCCA-C scores are reliable. Implications for research and practice are discussed.Davison, ML.; Seipel, B.; Clinton, V.; Carlson, S.; Kennedy, P.; Kennedy, PC. (2020). MOCCA College: An assessment of inferential narrative and expository comprehension. En 6th International Conference on Higher Education Advances (HEAd'20). Editorial Universitat PolitĂšcnica de ValĂšncia. (30-05-2020):417-425. https://doi.org/10.4995/HEAd20.2020.11081OCS41742530-05-202
Renegotiating chapter 121A agreements : legal and financial considerations
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1986.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH.by Patrick C. Kennedy.M.S
Retrieval of lower-order moments of the drop size distribution using CSU-CHILL X-band polarimetric radar: a case study
The lower-order moments of the drop size distribution (DSD) have generally been considered difficult to retrieve accurately from polarimetric radar data because these data are related to higher-order moments. For example, the 4.6th moment is associated with a specific differential phase and the 6th moment with reflectivity and ratio of high-order moments with differential reflectivity. Thus, conventionally, the emphasis has been to estimate rain rate (3.67th moment) or parameters of the exponential or gamma distribution for the DSD. Many double-moment âbulkâ microphysical schemes predict the total number concentration (the 0th moment of the DSD, or M0) and the mixing ratio (or equivalently, the 3rd moment M3). Thus, it is difficult to compare the model outputs directly with polarimetric radar observations or, given the model outputs, forward model the radar observables. This article describes the use of double-moment normalization of DSDs and the resulting stable intrinsic shape that can be fitted by the generalized gamma (G-G) distribution. The two reference moments are M3 and M6, which are shown to be retrievable using the X-band radar reflectivity, differential reflectivity, and specific attenuation (from the iterative correction of measured reflectivity Zh using the total Ίdp constraint, i.e., the iterative ZPHI method). Along with the climatological shape parameters of the G-G fit to the scaled/normalized DSDs, the lower-order moments are then retrieved more accurately than possible hitherto. The importance of measuring the complete DSD from 0.1âmm onwards is emphasized using, in our case, an optical array probe with 50â”m resolution collocated with a two-dimensional video disdrometer with about 170â”m resolution. This avoids small drop truncation and hence the accurate calculation of lower-order moments. A case study of a complex multi-cell storm which traversed an instrumented site near the CSU-CHILL radar is described for which the moments were retrieved from radar and compared with directly computed moments from the complete spectrum measurements using the aforementioned two disdrometers. Our detailed validation analysis of the radar-retrieved moments showed relative bias of the moments M0 through M2 was 0.9. Both radar measurement and parameterization errors were estimated rigorously. We show that the temporal variation of the radar-retrieved mass-weighted mean diameter with M0 resulted in coherent âtime tracksâ that can potentially lead to studies of precipitation evolution that have not been possible so far
A new narrow-beam, multi-frequency, scanning radiometer and its application to in-flight icing detection
AbstractA one degree beamwidth, multi-frequency (20 to 30 and 89GHz), dual-polarization radiometer with full azimuth and elevation scanning capabilities was built with the purpose of improving the detection of in-flight icing hazards to aircraft in the near airport environment. This goal was achieved by collocating the radiometer with Colorado State University's CHILL polarized Doppler radar and leveraging the similar beamwidth and volume scan regiments of the two instruments. The collocated instruments allowed for the liquid water path and water vapor measurements derived from the radiometer to be merged with the radar moment fields to determine microphysical and water phase characteristics aloft. The radiometer was field tested at Colorado State University's CHILL radar site near Greeley, Colorado during the summer of 2009. Instrument design, calibration, and initial field testing results are discussed in this paper
Variations of Little Higgs Models and their Electroweak Constraints
We calculate the tree-level electroweak precision constraints on a wide class
of little Higgs models including: variations of the Littlest Higgs SU(5)/SO(5),
SU(6)/Sp(6), and SU(4)^4/SU(3)^4. By performing a global fit to the precision
data we find that for generic regions of the parameter space the bound on the
symmetry breaking scale f is several TeV, where we have kept the normalization
of f constant in the different models. For example, the ``minimal''
implementation of SU(6)/Sp(6) is bounded by f>3.0 TeV throughout most of the
parameter space, and SU(4)^4/SU(3)^4 is bounded by f^2 = f_1^2+f_2^2 > (4.2
TeV)^2. In certain models, such as SU(4)^4/SU(3)^4, a large f does not directly
imply a large amount of fine tuning since the heavy fermion masses that
contribute to the Higgs mass can be lowered below f for a carefully chosen set
of parameters. We also find that for certain models (or variations) there exist
regions of parameter space in which the bound on f can be lowered into the
range 1-2 TeV. These regions are typically characterized by a small mixing
between heavy and standard model gauge bosons, and a small (or vanishing)
coupling between heavy U(1) gauge bosons and the light fermions. Whether such a
region of parameter space is natural or not is ultimately contingent on the UV
completion.Comment: 32 pages, 13 figures; revised discussion of SU(4)^4/SU(3)^4 model,
bound on f is slightly highe
An ALMA Survey of M-dwarfs in the Beta Pictoris Moving Group with Two New Debris Disc Detections
Previous surveys in the far-infrared have found very few, if any, M-dwarf
debris discs among their samples. It has been questioned whether M-dwarf discs
are simply less common than earlier types, or whether the low detection rate
derives from the wavelengths and sensitivities available to those studies. The
highly sensitive, long wavelength Atacama Large Millimetre/submillimetre Array
can shed light on the problem. This paper presents a survey of M-dwarf stars in
the young and nearby Beta Pictoris Moving Group with ALMA at Band 7
(880\,m). From the observational sample we detect two new sub-mm excesses
that likely constitute unresolved debris discs around GJ\,2006\,A and
AT\,Mic\,A and model distributions of the disc fractional luminosities and
temperatures. From the science sample of 36 M-dwarfs including AU\,Mic we find
a disc detection rate of 4/36 or 11.1\% that rises to
23.1\% when adjusted for completeness. We conclude that this
detection rate is consistent with the detection rate of discs around G and K
type stars and that the disc properties are also likely consistent with earlier
type stars. We additionally conclude that M-dwarf stars are not less likely to
host debris discs, but instead their detection requires longer wavelength and
higher sensitivity observations than have previously been employed.Comment: Accepted to MNRA
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