Extended range harmonic filter

Two types of filters, leaky-wall and open-guide, are combined into single component. Combination gives 10 db or greater additional attenuation to fourth and higher harmonics, at expense of increasing loss of fundamental frequency by perhaps 0.05 to 0.08 db. Filter is applicable to all high power microwave transmitters, but is especially desirable for satellite transmitters

Shuttle/spacelab MMAP/electromagnetic environment experiment phase B definition study

Progress made during the first five months of the Phase B definition study for the MMAP/Electromagnetic Environment Experiment (EEE) was described. An antenna/receiver assembly has been defined and sized for stowing in a three pallet bay area in the shuttle. Six scanning modes for the assembly are analyzed and footprints for various antenna sizes are plotted. Mission profiles have been outlined for a 400 km height, 57 deg inclination angle, circular orbit. Viewing time over 7 geographical areas are listed. Shuttle interfaces have been studied to determine what configuration the antenna assembly must have to be shared with other experiments of the Microwave Multi-Applications Payload (MMAP) and to be stowed in the shuttle bay. Other results reported include a frequency plan, a proposed antenna subsystem design, a proposed receiver design, preliminary outlines of the experiment controls and an analysis of on-board and ground data processing schemes

Corporations: An Untapped Resource for Higher Education Administrators who Seek to Enhance Student Learning

Higher education currently has a strict focus on the personal, intellectual, and social development of students. However, little attention is given to student development after college, particularly, to students who enter the real world and choose to work for a corporation. Colleges and corporations need to work together to assist students during the transition out of college and into the corporate workplace. Internships provide one means of cooperation between the two parties. This paper will explore how colleges and corporations can enhance student development and better prepare students for a post-collegiate corporate career

Debye mass and heavy quark potential in a PNJL quark plasma

We calculate the Debye mass for the screening of the heavy quark potential in a plasma of massless quarks coupled to the temporal gluon background governed by the Polyakov loop potential within the PNJL model in RPA approximation. We give a physical motivation for a recent phenomenological fit of lattice data by applying the calculated Debye mass with its suppression in the confined phase due to the Polyakov-loop to a description of the temperature dependence of the singlet free energy for QCD with a heavy quark pair at infinite separation. We compare the result to lattice data.Comment: 6 pages, 1 figure, contribution to Proceedings of the 6th International Conference on "Critical Point and Onset of Deconfinement", to appear in Phys. At. Nucl., vol. 7

A New 5 Flavour NLO Analysis and Parametrizations of Parton Distributions of the Real Photon

New, radiatively generated, NLO quark (u,d,s,c,b) and gluon densities in a real, unpolarized photon are presented. We perform three global fits, based on the NLO DGLAP evolution equations for Q^2>1 GeV^2, to all the available structure function F_2^gamma(x,Q^2) data. As in our previous LO analysis we utilize two theoretical approaches. Two models, denoted as FFNS_{CJK}1 & 2 NLO, adopt the so-called Fixed Flavour-Number Scheme for calculation of the heavy-quark contributions to F_2^gamma(x,Q^2), the CJK NLO model applies the ACOT(chi) scheme. We examine the results of our fits by a comparison with the LEP data for the Q^2 dependence of the F_2^gamma, averaged over various x-regions, and the F_2,c^gamma. Grid parametrizations of the parton densities for all fits are provided.Comment: 49 pages, 27 postscript figures; FORTRAN programs available at http://www.fuw.edu.pl/~pjank/param.htm

The appearance potency of gay and straight men’s websites

Gay men's greater body dissatisfaction compared to straight men has been explained as a result of gay men’s more 'appearance potent' subculture. This study aimed to critically appraise this explanation by assessing images of men and women for their physical characteristics and objectification across 8 popular gay and straight men's dating and porn websites. 1,415 images of men and 715 images of women across the website’s main pages were coded. Results showed that the gay men's websites featured more images of men that were appearance-ideal, nude, and sexualized in comparison to the straight men's websites. With the converse true for straight men’s websites. These results highlight the continuing need to develop and provide interventions that critique the appearance potency of popular media, particularly so for gay men

Mrgprd Enhances Excitability in Specific Populations of Cutaneous Murine Polymodal Nociceptors

The Mas-related G protein-coupled receptor D (Mrgprd) is selectively expressed in nonpeptidergic nociceptors that innervate the outer layers of mammalian skin. The function of Mrgprd in nociceptive neurons and the physiologically relevant somatosensory stimuli that activate Mrgprd^-expressing (Mrgprd^+) neurons are currently unknown. To address these issues, we studied three Mrgprd knock-in mouse lines using an ex vivo somatosensory preparation to examine the role of the Mrgprd receptor and Mrgprd+ afferents in cutaneous somatosensation. In mouse hairy skin, Mrgprd, as marked by expression of green fluorescent protein reporters, was expressed predominantly in the population of nonpeptidergic, TRPV1-negative, C-polymodal nociceptors. In mice lacking Mrgprd, this population of nociceptors exhibited decreased sensitivity to cold, heat, and mechanical stimuli. Additionally, in vitro patch-clamp studies were performed on cultured dorsal root ganglion neurons from Mrgprd^(–/–) and Mrgprd^(+/–) mice. These studies revealed a higher rheobase in neurons from Mrgprd^(–/–) mice than from Mrgprd^(+/–) mice. Furthermore, the application of the Mrgprd ligand β-alanine significantly reduced the rheobase and increased the firing rate in neurons from Mrgprd^(+/–) mice but was without effect in neurons from Mrgprd^(–/–) mice. Our results demonstrate that Mrgprd influences the excitability of polymodal nonpeptidergic nociceptors to mechanical and thermal stimuli

Plains Tectonism on Venus: The Deformation Belts of Lavinia Planitia

High-resolution radar images from the Magellan spacecraft have revealed the first details of the morphology of the Lavinia Planitia region of Venus. A number of geologic units can be distinguished, including volcanic plains units with a range of ages. Transecting these plains over much of the Lavinia region are two types of generally orthogonal features that we interpret to be compressional wrinkle ridges and extensional grooves. The dominant tectonic features of Lavinia are broad elevated belts of intense deformation that transect the plains with complex geometry. They are many tens to a few hundred kilometers wide, as much as 1000 km long, and elevated hundreds of meters above the surrounding plains. Two classes of deformation belts are seen in the Lavinia region. “Ridge belts” are composed of parallel ridges, each a few hundred meters in elevation, that we interpret to be folds. Typical fold spacings are 5–10 km. “Fracture belts” are dominated instead by intense faulting, with faults in some instances paired to form narrow grabens. There is also some evidence for modest amounts of horizontal shear distributed across both ridge and fracture belts. Crosscutting relationships among the belts show there to be a range in belt ages. In western Lavinia in particular, many ridge and fracture belts appear to bear a relationship to the much smaller wrinkle ridges and grooves on the surrounding plains: Ridge morphology tends to dominate belts that lie more nearly parallel to local plains wrinkle ridges, and fracture morphology tends to dominate belts that lie more nearly parallel to local plains grooves. We use simple models to explore the formation of ridge and fracture belts. We show that convective motions in the mantle can couple to the crust to cause horizontal stresses of a magnitude sufficient to induce the formation of deformation belts like those observed in Lavinia. We also use the small-scale wavelengths of deformation observed within individual ridge belts to place an approximate lower limit on the venusian thermal gradient in the Lavinia region at the time of deformation

"Peeling property" for linearized gravity in null coordinates

A complete description of the linearized gravitational field on a flat background is given in terms of gauge-independent quasilocal quantities. This is an extension of the results from gr-qc/9801068. Asymptotic spherical quasilocal parameterization of the Weyl field and its relation with Einstein equations is presented. The field equations are equivalent to the wave equation. A generalization for Schwarzschild background is developed and the axial part of gravitational field is fully analyzed. In the case of axial degree of freedom for linearized gravitational field the corresponding generalization of the d'Alembert operator is a Regge-Wheeler equation. Finally, the asymptotics at null infinity is investigated and strong peeling property for axial waves is proved.Comment: 27 page

Solute and sediment export from Amazon forest and soybean headwater streams

Author Posting. © Ecological Society of America, 2016. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecological Applications 27 (2017): 193–207, doi:10.1002/eap.1428.Intensive cropland agriculture commonly increases streamwater solute concentrations and export from small watersheds. In recent decades, the lowland tropics have become the world's largest and most important region of cropland expansion. Although the effects of intensive cropland agriculture on streamwater chemistry and watershed export have been widely studied in temperate regions, their effects in tropical regions are poorly understood. We sampled seven headwater streams draining watersheds in forest (n = 3) or soybeans (n = 4) to examine the effects of soybean cropping on stream solute concentrations and watershed export in a region of rapid soybean expansion in the Brazilian state of Mato Grosso. We measured stream flows and concentrations of NO3−, PO43−, SO42−, Cl−, NH4+, Ca2+, Mg2+, Na+, K+, Al3+, Fe3+, and dissolved organic carbon (DOC) biweekly to monthly to determine solute export. We also measured stormflows and stormflow solute concentrations in a subset of watersheds (two forest, two soybean) during two/three storms, and solutes and δ18O in groundwater, rainwater, and throughfall to characterize watershed flowpaths. Concentrations of all solutes except K+ varied seasonally in streamwater, but only Fe3+ concentrations differed between land uses. The highest streamwater and rainwater solute concentrations occurred during the peak season of wildfires in Mato Grosso, suggesting that regional changes in atmospheric composition and deposition influence seasonal stream solute concentrations. Despite no concentration differences between forest and soybean land uses, annual export of NH4+, PO43−, Ca2+, Fe3+, Na+, SO42−, DOC, and TSS were significantly higher from soybean than forest watersheds (5.6-fold mean increase). This increase largely reflected a 4.3-fold increase in water export from soybean watersheds. Despite this increase, total solute export per unit watershed area (i.e., yield) remained low for all watersheds (<1 kg NO3− N·ha−1·yr−1, <2.1 kg NH4+-N·ha−1·yr−1, <0.2 kg PO43−-P·ha−1·yr−1, <1.5 kg Ca2+·ha−1·yr−1). Responses of both streamflows and solute concentrations to crop agriculture appear to be controlled by high soil hydraulic conductivity, groundwater-dominated hydrologic flowpaths on deep soils, and the absence of nitrogen fertilization. To date, these factors have buffered streams from the large increases in solute concentrations that often accompany intensive croplands in other locations.NSF Grant Numbers: DEB-0640661, DEB-0949370; Fundação de Amparo á Pesquisa do Estado de São Paulo Grant Number: FAPESP 03/13172-2; Watson Graduate Student Fellowship; Center for Latin American and Caribbean Studies at Brown Universit