9,786 research outputs found
Feeding Patterns and Attachment Ability of \u3ci\u3eAltica Subplicata\u3c/i\u3e (Coleoptera: Chrysomelidae) on Sand-Dune Willow
To investigate feeding patterns of a specialist herbivore, Altica subplicata, larvae and adults were caged separately on host plants, Salix cordata, and leaf damage was estimated. Young, relatively more pubescent leaves near the tops of the shoots were consumed more than older leaves. Larvae clearly preferred the young, pubescent leaves and avoided the oldest leaves. Adults showed a stronger preference for the first five young leaves, but amount of consumption did not differ among the older leaves.
Attachment ability on smooth and pubescent leaves was examined as a possible factor influencing feeding patterns. Scanning electron microscopy of tarsal adhesive structures and leaf surfaces was conducted to investigate how A. subplicata attaches to its host. Adhesive setae on the tarsi of adults may be effective for attachment on the older, smooth leaves and their tarsal claws are likely used to cling to trichomes of pubescent leaves. Larvae have fleshy adhesive pads for attachment. Laboratory experiments on attachment of larvae and adults to smooth and pubescent leaves under various wind conditions showed that wind caused difficulty in attachment and movement, but leaf pubescence did not affect the number of beetles that fell off leaves. However, larvae fell off more quickly when placed on pubescent leaves. Thus, other factors such as nutritional quality and microclimate provided by trichomes may be responsible for the preference for pubescent leaves exhibited by A. subplicata
Book Reviews
DETECTION OF CRIME. By Lawrence P. Tiffany, Donald M. McIntyre, Jr.
LEGAL FICTIONS. By Lon L. Fuller.
PROPERTY LAW INDICTED! By W. Barton Leach
LAWYERS AND THE COURTS: A SOCIOLOGICAL STUDY OF THE ENGLISH LEGAL SYSTEM 1750-1965. By Brian Abel-Smith and Robert Stevens
Analytical description of spin-Rabi oscillation controlled electronic transitions rates between weakly coupled pairs of paramagnetic states with S=1/2
We report on an analytical description of spin-dependent electronic
transition rates which are controlled by a radiation induced spin-Rabi
oscillation of weakly spin-exchange and spin-dipolar coupled paramagnetic
states (S=1/2). The oscillation components (the Fourier content) of the net
transition rates within spin-pair ensembles are derived for randomly
distributed spin resonances with account of a possible correlation between the
two distributions that correspond to the two individual pair partners. The
results presented here show that when electrically or optically detected Rabi
spectroscopy is conducted under an increasing driving field B_ 1, the Rabi
spectrum evolves from a single resonance peak at s=\Omega_R, where
\Omega_R=\gamma B_1 is the Rabi frequency (\gamma is the gyromagnetic ratio),
to three peaks at s= \Omega_R, s=2\Omega_R, and at low s<< \Omega_R. The
crossover between the two regimes takes place when \Omega_R exceeds the
expectation value \delta_0 of the difference of the Zeeman energies within the
pairs, which corresponds to the broadening of the magnetic resonance lines in
the presence of disorder caused by hyperfine field or distributions of Lande
g-factors. We capture this crossover by analytically calculating the shapes of
all three peaks at arbitrary relation between \Omega_R and \delta_0. When the
peaks are well-developed their widths are \Delta s ~ \delta_0^2/\Omega_R.Comment: 10 page, 5 figure
R49 Radar Oleseruatiant of a Tarnada
Reprinted from BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY, Vol. 38, No. 10, December, 1957, pp. 591-595Preceding the development of a tornado at the ground a fingerline projection developed on the PPI in the SW corner of an echo. This was also visible on the three-dimensional models constructed from RHI data. The parent echo extended to 37,500 feet and was the highest echo in the vicinity. Tornado occurrence was simultaneous with a new cell merging with the finger. Photographs of the tornado, the lower level echo tilt, and winds aloft data all indicate the
same direction of shear
A Lightweight Loudspeaker for Aircraft Communications and Active Noise Control
A series of new, lightweight loudspeakers for use on commercial aircraft has been developed. The loudspeakers use NdFeB magnets and aluminum alloy frames to reduce the weight. The NdFeB magnet is virtually encapsulated by steel in the new speaker designs. Active noise reduction using internal loudspeakers was demonstrated to be effective in 1983. A weight, space, and cost efficient method for creating the active sound attenuating fields is to use the existing cabin loudspeakers for both communication and sound attenuation. This will require some additional loudspeaker design considerations
Finding the signal in the noise: Could social media be utilized for early hospital notification of multiple casualty events?
IntroductionDelayed notification and lack of early information hinder timely hospital based activations in large scale multiple casualty events. We hypothesized that Twitter real-time data would produce a unique and reproducible signal within minutes of multiple casualty events and we investigated the timing of the signal compared with other hospital disaster notification mechanisms.MethodsUsing disaster specific search terms, all relevant tweets from the event to 7 days post-event were analyzed for 5 recent US based multiple casualty events (Boston Bombing [BB], SF Plane Crash [SF], Napa Earthquake [NE], Sandy Hook [SH], and Marysville Shooting [MV]). Quantitative and qualitative analysis of tweet utilization were compared across events.ResultsOver 3.8 million tweets were analyzed (SH 1.8 m, BB 1.1m, SF 430k, MV 250k, NE 205k). Peak tweets per min ranged from 209-3326. The mean followers per tweeter ranged from 3382-9992 across events. Retweets were tweeted a mean of 82-564 times per event. Tweets occurred very rapidly for all events (<2 mins) and represented 1% of the total event specific tweets in a median of 13 minutes of the first 911 calls. A 200 tweets/min threshold was reached fastest with NE (2 min), BB (7 min), and SF (18 mins). If this threshold was utilized as a signaling mechanism to place local hospitals on standby for possible large scale events, in all case studies, this signal would have preceded patient arrival. Importantly, this threshold for signaling would also have preceded traditional disaster notification mechanisms in SF, NE, and simultaneous with BB and MV.ConclusionsSocial media data has demonstrated that this mechanism is a powerful, predictable, and potentially important resource for optimizing disaster response. Further investigated is warranted to assess the utility of prospective signally thresholds for hospital based activation
Deformation of continental crust along a transform boundary, Coast Mountains, British Columbia
New structural, paleomagnetic, and apatite (U-Th)/He results from the continental margin inboard of the Queen Charlotte fault (~54Ā°N) delineate patterns of brittle faulting linked to transform development since ~50 Ma. In the core of the orogen, ~250 km from the transform, north striking, dip-slip brittle faults and vertical axis rotation of large crustal domains occurred after ~50 Ma and before intrusion of mafic dikes at 20 Ma. By 20 Ma, dextral faulting was active in the core of the orogen, but extension had migrated toward the transform, continuing there until <9 Ma. Local tilting in the core of the orogen is associated with glacially driven, post-4 Ma exhumation. Integration with previous results shows that post-50 Ma dextral and normal faulting affected a region ~250 km inboard of the transform and ~300 km along strike. Initially widespread, the zone of active extension narrowed and migrated toward the transform ~25 Ma after initiation of the transform, while dextral faulting continued throughout the region. Differential amounts of post-50 Ma extension created oroclines at the southern and northern boundaries of the deformed region. This region approximately corresponds to continental crust that was highly extended just prior to transform initiation. Variation in Neogene crustal tilts weakens interpretations relying on uniform tilting to explain anomalous paleomagnetic inclinations of mid-Cretaceous plutons. Similarities to the Gulf of California suggest that development of a transform in continental crust is aided by previous crustal extension and that initially widespread extension narrows and moves toward the transform as the margin develops
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Intense molecular emission from the Lagoon nebula, M8
The discovery is reported of the second strongest source of mm and submm wavelength CO line emission, towards M8, the Lagoon Nebula in Sagittarius. The ~31 Mā molecular core has dimensions ~0.2 x 0.3pc and is centred on the O7V star Herschel 36 (H36), near the Hourglass Nebula in the core of M8. Emission from the CO line wings extends to the north and south of the Hourglass, although a lack of near-IR H2 emission indicates that outflow activity is much less prominent than in many active star-formation regions, and suggests that the CO line wings may trace the expanding edge of a cavity around H36. The molecular line data are compared with new near-IR narrow-band, continuum-subtracted images in He I, H2, and H,+ (BrĪ³) lines and archival HST emission-line images in HĪ±, [O III], and [S II]. The optical and near-IR data are found to be broadly consistent with previous photo-ionisation models of the Hourglass, which is excited by H 36. However, there are variations in the He I/BrĪ³ line ratio which are difficult to explain
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