3,386 research outputs found
Demonstration of Sex Pheromones in \u3ci\u3eMolanna Uniophila\u3c/i\u3e (Trichoptera: Molannidae), \u3ci\u3ePlatycentropus Radiatus, Pycnopsyche Indiana, and P. Subfasciata\u3c/i\u3e (Trichoptera: Limnephilidae), With an Assessment of Interspecific Attraction Between Four Sympatric \u3ci\u3ePycnopsyche\u3c/i\u3e Species
Evidence for sex pheromones in the caddisflies Molanna uniophila Vorhies, Platycentropus radiatus (Say), Pycnopsyche indiana (Ross), and P. subfasciata (Say) is presented here for the first time based on field studies conducted in southern Michigan. For all species, numbers of males caught in pheromone traps baited with conspecific female extracts were higher than those caught in traps with male extracts, or those without extract. Four sympatric species of Pycnopsyche: P. guttifer (Walker), P. indiana, P. lepida (Hagen), and P. subfasciata exhibited no interspecific pheromonal attraction despite a common mating season and, in the case of P. indiana and P. lepida, very similar genitalic morphology. Our results suggest the importance of pheromones in maintaining reproductive isolation between closely related species. Likewise, pheromone biology can help delineate morphologically cryptic species
Comparisons of wing pressure distribution from flight tests of flush and external orifices for Mach numbers from 0.50 to 0.97
Wing pressure distributions obtained in flight with flush orifice and external tubing orifice installations for Mach numbers from 0.50 to 0.97 are compared. The procedure used to install the external tubing orifice is discussed. The results indicate that external tubing orifice installations can give useful results
Complete Photoionization Experiments via Ultrafast Coherent Control with Polarization Multiplexing II: Numerics & Analysis Methodologies
The feasibility of complete photoionization experiments, in which the full
set of photoionization matrix elements are determined, using multiphoton
ionization schemes with polarization-shaped pulses has recently been
demonstrated [Hockett et. al., Phys. Rev. Lett. 112, 223001 (2014)]. Here we
extend on our previous work to discuss further details of the numerics and
analysis methodology utilised, and compare the results directly to new
tomographic photoelectron measurements, which provide a more sensitive test of
the validity of the results. In so doing we discuss in detail the physics of
the photoionziation process, and suggest various avenues and prospects for this
coherent multiplexing methodology
National Income, Strategic Discontinuity, and Converging Trajectories of Macroeconomic Policy Initiatives: An Empirical Study of China
The framework of converging trajectories of macroeconomic policy initiatives is employed in the context of strategic discontinuity to study the national income of an advancing economy. A model of systemic changes based upon an equation of production and consumption is presented. In this study of the Chinese economy of 1980-2014, over time, the dynamics of policy imbalance is found to decrease considerably, which is consistent with the decreasing trend of shrinking the differences among the impact coefficients of government consumption, private investment, and private consumption
Maximum information photoelectron metrology
Photoelectron interferograms, manifested in photoelectron angular
distributions (PADs), are a high-information, coherent observable. In order to
obtain the maximum information from angle-resolved photoionization experiments
it is desirable to record the full, 3D, photoelectron momentum distribution.
Here we apply tomographic reconstruction techniques to obtain such 3D
distributions from multiphoton ionization of potassium atoms, and fully analyse
the energy and angular content of the 3D data. The PADs obtained as a function
of energy indicate good agreement with previous 2D data and detailed analysis
[Hockett et. al., Phys. Rev. Lett. 112, 223001 (2014)] over the main spectral
features, but also indicate unexpected symmetry-breaking in certain regions of
momentum space, thus revealing additional continuum interferences which cannot
otherwise be observed. These observations reflect the presence of additional
ionization pathways and, most generally, illustrate the power of maximum
information measurements of this coherent observable
Demonstration of Sex Pheromones in \u3ci\u3eMolanna Uniophila\u3c/i\u3e (Trichoptera: Molannidae), \u3ci\u3ePlatycentropus Radiatus, Pycnopsyche Indiana, and P. Subfasciata\u3c/i\u3e (Trichoptera: Limnephilidae), With an Assessment of Interspecific Attraction Between Four Sympatric \u3ci\u3ePycnopsyche\u3c/i\u3e Species
Evidence for sex pheromones in the caddisflies Molanna uniophila Vorhies, Platycentropus radiatus (Say), Pycnopsyche indiana (Ross), and P. subfasciata (Say) is presented here for the first time based on field studies conducted in southern Michigan. For all species, numbers of males caught in pheromone traps baited with conspecific female extracts were higher than those caught in traps with male extracts, or those without extract. Four sympatric species of Pycnopsyche: P. guttifer (Walker), P. indiana, P. lepida (Hagen), and P. subfasciata exhibited no interspecific pheromonal attraction despite a common mating season and, in the case of P. indiana and P. lepida, very similar genitalic morphology. Our results suggest the importance of pheromones in maintaining reproductive isolation between closely related species. Likewise, pheromone biology can help delineate morphologically cryptic species
Space-Based Reconfigurable Software Defined Radio Test Bed Aboard International Space Station
The National Aeronautical and Space Administration (NASA) recently launched a new software defined radio research test bed to the International Space Station. The test bed, sponsored by the Space Communications and Navigation (SCaN) Office within NASA is referred to as the SCaN Testbed. The SCaN Testbed is a highly capable communications system, composed of three software defined radios, integrated into a flight system, and mounted to the truss of the International Space Station. Software defined radios offer the future promise of in-flight reconfigurability, autonomy, and eventually cognitive operation. The adoption of software defined radios offers space missions a new way to develop and operate space transceivers for communications and navigation. Reconfigurable or software defined radios with communications and navigation functions implemented in software or VHDL (Very High Speed Hardware Description Language) provide the capability to change the functionality of the radio during development or after launch. The ability to change the operating characteristics of a radio through software once deployed to space offers the flexibility to adapt to new science opportunities, recover from anomalies within the science payload or communication system, and potentially reduce development cost and risk by adapting generic space platforms to meet specific mission requirements. The software defined radios on the SCaN Testbed are each compliant to NASA's Space Telecommunications Radio System (STRS) Architecture. The STRS Architecture is an open, non-proprietary architecture that defines interfaces for the connections between radio components. It provides an operating environment to abstract the communication waveform application from the underlying platform specific hardware such as digital-to-analog converters, analog-to-digital converters, oscillators, RF attenuators, automatic gain control circuits, FPGAs, general-purpose processors, etc. and the interconnections among different radio components
- …