451 research outputs found
Acoustically evoked potentials in two cephalopods inferred using the auditory brainstem response (ABR) approach
It is still a matter of debate whether cephalopods can detect sound frequencies above 400 Hz. So far there is no proof for the detection of underwater sound above 400 Hz via a physiological approach. The controversy of whether cephalopods have a sound detection ability above 400 Hz was tested using the auditory brainstem response (ABR) approach, which has been successfully applied in fish, crustaceans, amphibians, reptiles and birds. Using ABR we found that auditory evoked potentials can be obtained in the frequency range 400 to 1500 Hz (Sepiotheutis lessoniana) and 400 to 1000 Hz (Octopus vulgaris), respectively. The thresholds of S. lessoniana were generally lower than those of O. vulgaris
Enhancing PCR Amplification of DNA From Recalcitrant Plant Specimens Using a Trelahose-Based Additive
Premise of the study: PCR amplification of DNA extracted from plants is sometimes difficult due to the presence of inhibitory compounds. An effective method to overcome the inhibitory effect of compounds that contaminate DNA from difficult plant specimens is needed.
Methods and Results: The effectiveness of a PCR additive reagent containing trehalose, bovine serum albumin (BSA), and polysorbateâ20 (Tweenâ20) (TBTâPAR) was tested. PCR of DNA extracted from fresh, silicaâdried, and herbarium leaf material of species of Achariaceae, Asteraceae, Lacistemataceae, and Samydaceae that failed using standard techniques were successful with the addition of TBTâPAR.
Conclusions: The addition of TBTâPAR during routine PCR is an effective method to improve amplification of DNA extracted from herbarium specimens or plants that are known to contain PCR inhibitors
Taselisib (GDC-0032), a Potent  -Sparing Small Molecule Inhibitor of PI3K, Radiosensitizes Head and Neck Squamous Carcinomas Containing Activating PIK3CA Alterations
Activating PIK3CA genomic alterations are frequent in head and neck squamous cell carcinoma (HNSCC), and there is an association between phosphoinositide 3-kinase (PI3K) signaling and radioresistance. Hence, we investigated the therapeutic efficacy of inhibiting PI3K with GDC-0032, a PI3K inhibitor with potent activity against p110α, in combination with radiation in HNSCC
Performance of two Askaryan Radio Array stations and first results in the search for ultra-high energy neutrinos
Ultra-high energy neutrinos are interesting messenger particles since, if
detected, they can transmit exclusive information about ultra-high energy
processes in the Universe. These particles, with energies above
, interact very rarely. Therefore, detectors that
instrument several gigatons of matter are needed to discover them. The ARA
detector is currently being constructed at South Pole. It is designed to use
the Askaryan effect, the emission of radio waves from neutrino-induced cascades
in the South Pole ice, to detect neutrino interactions at very high energies.
With antennas distributed among 37 widely-separated stations in the ice, such
interactions can be observed in a volume of several hundred cubic kilometers.
Currently 3 deep ARA stations are deployed in the ice of which two have been
taking data since the beginning of the year 2013. In this publication, the ARA
detector "as-built" and calibrations are described. Furthermore, the data
reduction methods used to distinguish the rare radio signals from overwhelming
backgrounds of thermal and anthropogenic origin are presented. Using data from
only two stations over a short exposure time of 10 months, a neutrino flux
limit of is
calculated for a particle energy of 10^{18}eV, which offers promise for the
full ARA detector.Comment: 21 pages, 34 figures, 1 table, includes supplementary materia
ASME 88-1CE-6, presented at the Energy-Source Technology Conference and Exhibition
Fig. 5 Velocity versus anguiar dispiacement (V8 engine) attained from the inertia value using the least squares method is consistently smaller than the reference data, and eventually leads to larger velocity estimation error than the average method Some precautions are needed when applying the least squares method to compute the engine inertia value. For engines operating at high speeds, the velocity related term in Eq. (1) could be very large compared with the other terms. This could result in some confusing situations. For instance, engines might decelerate over some portion of the engine operation cycle while the net external torque accelerating the engine is positive; or engines might accelerate while the net external torque is negative. These operation situations might make negative engine inertia value estimations possible, which is not feasible. In other cases, engines might have very small accelerations or decelerations while net external torque is moderate to large. For these cases, the calculation might lead to very large engine inertia values, which is not feasible either. The cases mentioned above are most likely to occur when engines operate at high speeds. Those erroneous data corresponding the situations above must be Altered out before applying the least squares method to the engine inertia value computation. The criterion used in this study to decide whether data should be used to calculate the engine inertia values is to check the quotient of the net external torque divided by the engine acceleration. This quotient should not be too large or too small relative to the average engine inertia value. Those data whose quotient are significantly away from the average engine inertia value are likely to fall in the situations mentioned above, and those data should not be used in the engine inertia value computation. V Conclusions The engine inertia values calculated by the least squares method guarantees minimum acceleration and velocity estimation errors for engine operating at constant average velocities. As for monotonically accelerating and decelerating engines, simulations in the study show that the engine model with an inertia calculated by the least squares method leads to smaller estimation errors in acceleration but larger estimation errors in velocity than the constant inertia engine model with an average inertia. It is important that the user knows the type of engine, its range of operation, and the type of loading in order to calculate an optimal engine inertia for the control purpose. This study has provided guidance in understanding the effects of engine performance variables and in calculating an appropriate estimate for the engine inertia. Acknowledgment
White Paper: ARIANNA-200 high energy neutrino telescope
The proposed ARIANNA-200 neutrino detector, located at sea-level on the Ross
Ice Shelf, Antarctica, consists of 200 autonomous and independent detector
stations separated by 1 kilometer in a uniform triangular mesh, and serves as a
pathfinder mission for the future IceCube-Gen2 project. The primary science
mission of ARIANNA-200 is to search for sources of neutrinos with energies
greater than 10^17 eV, complementing the reach of IceCube. An ARIANNA
observation of a neutrino source would provide strong insight into the
enigmatic sources of cosmic rays. ARIANNA observes the radio emission from high
energy neutrino interactions in the Antarctic ice. Among radio based concepts
under current investigation, ARIANNA-200 would uniquely survey the vast
majority of the southern sky at any instant in time, and an important region of
the northern sky, by virtue of its location on the surface of the Ross Ice
Shelf in Antarctica. The broad sky coverage is specific to the Moore's Bay
site, and makes ARIANNA-200 ideally suited to contribute to the multi-messenger
thrust by the US National Science Foundation, Windows on the Universe -
Multi-Messenger Astrophysics, providing capabilities to observe explosive
sources from unknown directions. The ARIANNA architecture is designed to
measure the angular direction to within 3 degrees for every neutrino candidate,
which too plays an important role in the pursuit of multi-messenger
observations of astrophysical sources
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