3,189 research outputs found
Venus Radar Mapper (VRM): Multimode radar system design
The surface of Venus has remained a relative mystery because of the very dense atmosphere that is opaque to visible radiation and, thus, normal photographic techniques used to explore the other terrestrial objects in the solar system are useless. The atmosphere is, however, almost transparent to radar waves and images of the surface have been produced via Earth-based and orbital radars. The technique of obtaining radar images of a surface is variously called side looking radar, imaging radar, or synthetic aperture radar (SAR). The radar requires a moving platform in which the antenna is side looking. High resolution is obtained in the cross-track or range direction by conventional radar pulse encoding. In the along-track or azimuth direction, the resolution would normally be the antenna beam width, but for the SAR case, a much longer antenna (or much sharper beam) is obtained by moving past a surface target as shown, and then combining the echoes from many pulses, by using the Doppler data, to obtain the images. The radar design of the Venus Radar Mapper (VRM) is discussed. It will acquire global radar imagery and altimetry data of the surface of Venus
EC88-217 Crossbreeding Systems for Commercial Pork Production
Extension circular 88-217 is about crossbreeding system for commercial, pork production
Old-growth and mature forests near spotted owl nests in western Oregon
We investigated how the amount of old-growth and mature forest influences the selection of nest sites by northern spotted owls (Strix occidentalis caurina) in the Central Cascade Mountains of Oregon. We used 7 different plot sizes to compare the proportion of mature and old-growth forest between 30 nest sites and 30 random sites. The proportion of old-growth and mature forest was significantly greater at nests sites than at random sites for all plot sizes (P less than or equal to 0.01). Thus, management of the spotted owl might require setting the percentage of old-growth and mature forest retained from harvesting at least 1 standard deviation above the mean for the 30 nest sites we examined
CG2Real: Improving the Realism of Computer Generated Images using a Large Collection of Photographs
Computer Graphics (CG) has achieved a high level of realism, producing strikingly vivid images. This realism, however, comes at the cost of long and often expensive manual modeling, and most often humans can still distinguish between CG images and real images. We present a novel method to make CG images look more realistic that is simple and accessible to novice users. Our system uses a large collection of photographs gathered from online repositories. Given a CG image, we retrieve a small number of real images with similar global structure. We identify corresponding regions between the CG and real images using a novel mean-shift cosegmentation algorithm. The user can then automatically transfer color, tone, and texture from matching regions to the CG image. Our system only uses image processing operations and does not require a 3D model of the scene, making it fast and easy to integrate into digital content creation workflows. Results of a user study show that our improved CG images appear more realistic than the originals
Testing limits to airflow perturbation device (APD) measurements
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Factors Influencing Sun Protection Behaviors among Patients with Skin Cancer: An Application of the Information-Motivation-Behavioral Skills Model
© 2019 by the Dermatology Nurses\u27 Association. This study aimed to assess predictors of sun protection behaviors based on the information-motivation-behavioral skills (IMB) model among people diagnosed with nonmelanoma skin cancer (NMSC). For this descriptive, cross-sectional study, a convenience sample of 311 patients with NMSC was recruited at a medical center in Mississippi. Patients were invited to complete a face- A nd content-valid, IMB-model-based questionnaire. The average age of the participants was 64.12 (±12.02) years, and most (58.8%) were male. Most participants indicated not using sun protection behaviors while outdoors. Findings showed that sun protection behaviors were directly predicted by self-efficacy (standardized path coefficient = 0.504, p \u3c.001) and social support (standardized path coefficient = 0.199, p =.010). In addition, sun protection behavior was indirectly predicted (through self-efficacy) by social support (standardized indirect effect = 0.160, p \u3c.001) and attitudes (standardized indirect effect = 0.192, p =.001). The explained variances for self-efficacy and sun protection behaviors were 43% and 35.4%, respectively. In conclusion, the IMB model appears to be a useful theoretical framework for predicting sun protection behaviors among patients with NMSC. Sun safety intervention programs should be developed based on this theoretical model for patients with NMSC
Reduced Translocation Is Associated with Tolerance of Common Lambsquarters (\u3ci\u3eChenopodium album\u3c/i\u3e) to Glyphosate
Common lambsquarters tolerance to glyphosate is problematic because of the species’ widespread distribution, competitive ability with many crop species, the widespread use of glyphosate in agriculture, and the weed’s potential to develop decreased sensitivity to multiple herbicide sites of action. The mechanism that confers common lambsquarters tolerance to glyphosate is not known. Therefore, we conducted experiments to determine the mechanism of tolerance to glyphosate in an accession of common lambsquarters from Indiana relative to a sensitive accession from Wisconsin. The ED50 (the effective dose that reduced shoot mass 50% relative to nontreated plants) value for the tolerant accession (1.6 kg ae ha-1 ± 0.4 standard error of the mean [SEM]) was eightfold greater than the ED50 for the sensitive accession (0.2 kg ae ha-1 ± 0.2 SEM) 28 d after treatment. The glyphosate target-site (EPSPS) DNA sequence at proline 106, shikimate accumulation as an estimate of EPSPS sensitivity, and EPSPS protein abundance did not differ between accessions. Absorption of 14Cglyphosate was slightly greater in the tolerant accession than it was in the sensitive accession at 48 and 72 h after treatment (HAT). However, the tolerant accession translocated a smaller percentage of absorbed 14C-glyphosate to the tissue above the treated leaf, which included the shoot apical meristem, at 24, 48, and 72 HAT (P ≤ 0.05, 0.01, and 0.10, respectively). These results suggest an important role of reduced translocation in conferring tolerance of common lambsquarters to glyphosate
Ground Processing of Cassini RADAR Imagery of Titan
The Cassini RADAR instrument onboard
the Cassini Orbiter is currently collecting
SAR Imagery of the surface of Saturn's largest
moon, Titan. This paper describes the ground
processing of Cassini SAR data. We focus upon the
unusual features of the data and how these features
impact the processing. We exhibit a data dependent
mechanism we have implemented for eliminating
artifacts due to attitude and ephemeris knowledge
error. Finally we describe how we trade-off SAR
performance vs. area of coverage when we design
our spacecraft pointing profiles
Global analysis of differential gene expression within the porcine conceptus transcriptome as it transitions through spherical, ovoid, and tubular morphologies during the initiation of elongation
This study aimed to identify transcriptome differences between distinct or transitional stage spherical, ovoid, and tubular porcine blastocysts throughout the initiation of elongation. We performed a global transcriptome analysis of differential gene expression using RNA‐Seq with high temporal resolution between spherical, ovoid, and tubular stage blastocysts at specific sequential stages of development from litters containing conceptus populations of distinct or transitional blastocysts. After RNA‐Seq analysis, significant differentially expressed genes (DEGs) and pathways were identified between distinct morphologies or sequential development stages. Overall, 1898 significant DEGs were identified between distinct spherical and ovoid morphologies, with 311 total DEGs between developmental stages throughout this first morphological transition, while 15 were identified between distinct ovoid and tubular, with eight total throughout these second morphological transition developmental stages. The high quantity of DEGs and pathways between conceptus stages throughout the spherical to ovoid transition suggests the importance of gene regulation during this first morphological transition for initiating elongation. Further, extensive DEG coverage of known elongation signaling pathways was illustrated from spherical to ovoid, and regulation of lipid signaling and membrane/ECM remodeling across these early conceptus stages were implicated as essential to this process, providing novel insights into potential mechanisms governing this rapid morphological change
3D excretory MR urography: Improved image quality with intravenous saline and diuretic administration
Purpose To assess the effect of diuretic administration on the image quality of excretory magnetic resonance urography (MRU) obtained following intravenous hydration, and to determine whether intravenous hydration alone is sufficient to produce diagnostic quality studies of nondilated upper tracts. Materials and Methods A total of 22 patients with nondilated upper tracts were evaluated with contrast-enhanced MRU. All patients received 250 mL of saline intravenously immediately prior to the examination. A total of 11 patients received 10–20 mg furosemide in addition to saline. Imaging was performed with a three-dimensional (3D) and two-dimensional (2D) breathhold spoiled gradient-echo sequences. Excretory MRU images were acquired five minutes after the administration of 0.1 mmol/kg gadolinium and were independently reviewed by two radiologists, who were blinded to the MRU technique. Readers evaluated the calyces, renal pelvis, and ureters qualitatively for degree of opacification, distention, and artifacts on a four-point scale. Statistical analysis was performed using a permutation test. Results There was no significant disagreement between the two readers ( P = 0.14). Furosemide resulted in significant improvement in calyceal and renal pelvis distention ( P < 0.005), and significant artifact reduction in all upper tract segments ( P < 0.001) compared to the effect of saline alone. Conclusion Intravenous furosemide significantly improves the image quality of excretory MRU studies obtained following intravenous hydration. Intravenous saline alone is insufficient to produce diagnostic quality studies of the non-dilated upper tracts. J. Magn. Reson. Imaging 2007. © 2007 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/56023/1/20875_ftp.pd
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