16,175 research outputs found
The Growth and Survival of Early Instars of \u3ci\u3eBellura Obliqua\u3c/i\u3e (Lepidoptera: Noctuidae) on \u3ci\u3eTypha Latifolia\u3c/i\u3e and \u3ci\u3eTypha Angustifolia\u3c/i\u3e
Larvae of the noctuid moth Bellura obliqua are frequently encountered on Typha latifolia, but less commonly on Typha angustifolia. Experiments were conducted to compare the growth and survivorship of early B. obliqua instars on the two species of cattail. In short-term growth chamber experiments there were no significant differences in the survivorship, relative growth rate (RGR), relative consumption rate (RCR), or the efficiency of conversion of ingested food (ECI) between first-instar larvae reared on leaves of the two species. Third-instar larvae fed stems, however, had a greater RGR and higher ECI when reared on T. lalifolia. Differences in growth are apparently not related to differences in hostplant nitrogen or acid-detergent fiber content. In a long term greenhouse experiment, using transplanted cattails, larvae reared on T. latifolia grew somewhat larger and had a significantly higher survival rate than those reared on T. angustifolia. Host plant structure is postulated to influence larval survivorship. Typha is under consideration for use as a bio-energy crop and planting T. angustifolia may help to reduce infestations in cultivated stands
Entanglement and the modern Australian rhythm method: Lantana's lessons in policing sexuality and gender
Film in Australia, as with many other nations, is often seen as an important cultural medium where national stories about belonging and identity can be (re)produced in pleasurable and, at times, complicated ways. One such film is Ray Lawrence’s Lantana. Although striking a chord in Australia as a good film about ‘ basically good people’, people that rang ‘brilliantly’ true (Lantana DVD 2002), this paper argues that, at the same time as it produces a fantasy of a ‘good’ Australia, the film also conducts a regulation of what constitutes Australianness. In many ways the imaginary of Australia offered in this film, to its contemporary, urban, professional and intellectual elite audience, still draws on and (re)produces a vision of an Australian community that uses the same narrative frameworks of protection and control as the cruder discourses of ‘white Australia’ offered to an earlier generation of cinema-goers. This film’s central motif of the lantana bush, the out of control weed, that is known as both foreign and local is here emblematic of tensions about belonging, place and otherness. Yet while, within the film’s knowingly reflexive purview any remaining potential for racism is understood and itself under control – we know how to be good mutliculturalists –it is the trope of sexuality in Lantana that provides the real sense of edginess and anxiety about belonging. It is in this arena that the film sets up an idea of danger and –less self-consciously, and in the end more aggressively – marks out who is and who is not part of the community. In this context the motif of lantana signals an ambivalence about difference and the exotic. Lantana is both desirable because of the difference in its attractive Latin looks and repulsive or feared because of other qualities inherent within its difference: a refusal to behave and a propensity to get out-of control, spread and potentially take over. The film here explores desire for a taste of the other (a gay man, a newly separated woman, a Latin dance teacher). However, these fantasies are in the end emphatically shut down as the film ends by producing a vision of subtly normalised hetero, mono, familial (though not necessarily happy) forms of desiring, loving and reproducing in contemporary Australia
Transonic flutter study of a wind-tunnel model of an arrow-wing supersonic transport
A 1/20-size, low-speed flutter model of the SCAT-15F complete airplane was tested on cables to simulate a near free-flying condition. Only the model wing and fuselage were flexible. Flutter boundaries were measured for a nominal configuration and a configuration with wing fins removed at Mach numbers M from 0.76 to 1.2. For both configurations, the transonic dip in the wing flutter dynamic pressure q boundary was relatively small and the minimum flutter q occurred near M = 0.92. Removing the wing fins increased the flutter q about 14 percent and changed the flutter mode from symmetric to antisymmetric. Vibration and flutter analyses were made using a finite-element structural representation and subsonic kernel-function aerodynamics. For the nominal configuration, the analysis (using calculated modal data) predicted the experimental flutter q levels within 10 percent but did not predict the correct flutter mode at the higher M. For the configuration without wing fins, the analysis predicted 16 to 36 percent unconservative (higher than experimental) flutter q levels and showed extreme sensitivity to mass representation details that affected wing tip mode shapes. For high subsonic M, empennage aerodynamics had a significant effect on the predicted flutter boundaries of several symmetric modes
Fluctuation dynamo amplified by intermittent shear bursts in convectively driven magnetohydrodynamic turbulence
Intermittent large-scale high-shear flows are found to occur frequently and
spontaneously in direct numerical simulations of statistically stationary
turbulent Boussinesq magnetohydrodynamic (MHD) convection. The energetic
steady-state of the system is sustained by convective driving of the velocity
field and small-scale dynamo action. The intermittent emergence of flow
structures with strong velocity and magnetic shearing generates magnetic energy
at an elevated rate over time-scales longer than the characteristic time of the
large-scale convective motion. The resilience of magnetic energy amplification
suggests that intermittent shear-bursts are a significant driver of dynamo
action in turbulent magnetoconvection
Pratt Motor Company Records - Accession 1608
The collection consists of Log books of payments made to the Pratt Motor Company based in Rock Hill, S.C. and founded by Crawford C. Pratt (1910-1957) with client information, payment dates, addresses, and the make, model and year of vehicle sold. Information also includes serial numbers and motor numbers of vehicles. Some motor vehicle registrations are present, as well as a title.https://digitalcommons.winthrop.edu/manuscriptcollection_findingaids/2611/thumbnail.jp
Extreme-value statistics from Lagrangian convex hull analysis for homogeneous turbulent Boussinesq convection and MHD convection
We investigate the utility of the convex hull of many Lagrangian tracers to
analyze transport properties of turbulent flows with different anisotropy. In
direct numerical simulations of statistically homogeneous and stationary
Navier-Stokes turbulence, neutral fluid Boussinesq convection, and MHD
Boussinesq convection a comparison with Lagrangian pair dispersion shows that
convex hull statistics capture the asymptotic dispersive behavior of a large
group of passive tracer particles. Moreover, convex hull analysis provides
additional information on the sub-ensemble of tracers that on average disperse
most efficiently in the form of extreme value statistics and flow anisotropy
via the geometric properties of the convex hulls. We use the convex hull
surface geometry to examine the anisotropy that occurs in turbulent convection.
Applying extreme value theory, we show that the maximal square extensions of
convex hull vertices are well described by a classic extreme value
distribution, the Gumbel distribution. During turbulent convection,
intermittent convective plumes grow and accelerate the dispersion of Lagrangian
tracers. Convex hull analysis yields information that supplements standard
Lagrangian analysis of coherent turbulent structures and their influence on the
global statistics of the flow.Comment: 18 pages, 10 figures, preprin
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