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Sample records for analysis sheds light

  1. Mitochondrial analysis sheds light on the origin of hair sheep.

    PubMed

    Álvarez, I; Capote, J; Traoré, A; Fonseca, N; Pérez, K; Cuervo, M; Fernández, I; Goyache, F

    2013-06-01

    A total of 180 mtDNA sequences from hair Caribbean (93), West African (73) and Canarian-wooled (14) sheep were analysed to shed light on the origin of hair sheep. A comparison of 360 Iberian sheep sequences retrieved from GenBank was performed to assess a possible European origin of the Caribbean hair sheep. These 180 sequences gave 48 different haplotypes (16 in Caribbean sheep). All Caribbean and Canarian-wooled sequences and 91.8% of the West African samples belonged to haplogroup B. The sheep analysed showed wide haplotypic identity. Caribbean sheep shared roughly two-thirds of their samples with Canarian-wooled and West African samples, respectively. Principal component analysis showed that the Caribbean and the Canarian-wooled sheep clustered together. Additional analyses showed that hair and Iberian sheep had wide genetic identity. It was not possible to ascertain a single Canarian, African or European origin of the Caribbean hair sheep using mtDNA markers only. European, African and Caribbean hair sheep maternal genetic backgrounds likely result from related domestication events. PMID:23020288

  2. Shedding Some Light.

    ERIC Educational Resources Information Center

    Whitney, Tim

    1998-01-01

    Discusses the basics of designing natural and artificial light in an indoor athletic facility. Also examines individual lighting requirements of typical rooms such as weight and fitness rooms, aerobics and multipurpose rooms, gymnasiums, field houses, pools, and racquetball and squash courts. (GR)

  3. Shedding Light on Learning.

    ERIC Educational Resources Information Center

    Graves, Ben E.

    1985-01-01

    Summarizes findings of an Alberta light/color study that looked at mood, noise levels, IQ test scores, blood pressure, and absences under fluorescent or full-spectrum light in two color schemes in four elementary schools with 700 students. (MLF)

  4. Shedding Light on Nanomedicine

    PubMed Central

    Tong, Rong

    2012-01-01

    Light is electromagnetic radiation that can convert its energy into different forms (e.g., heat, chemical energy, and acoustic waves). This property has been exploited in phototherapy (e.g., photothermal therapy and photodynamic therapy) and optical imaging (e.g., fluorescence imaging) for therapeutic and diagnostic purposes. Light-controlled therapies can provide minimally or non-invasive spatiotemporal control as well as deep tissue penetration. Nanotechnology provides a numerous advantages, including selective targeting of tissues, prolongation of therapeutic effect, protection of active payloads, and improved therapeutic indices. This review explores the advances that nanotechnology can bring to light-based therapies and diagnostics, and vice versa, including photo-triggered systems, nanoparticles containing photoactive molecules, and nanoparticles that are themselves photoactive. Limitations of light-based therapies such as photic injury and phototoxicity will be discussed. PMID:22887840

  5. Shedding light on prion disease

    PubMed Central

    Glatzel, Markus; Linsenmeier, Luise; Dohler, Frank; Krasemann, Susanne; Puig, Berta; Altmeppen, Hermann C

    2015-01-01

    ABSTRACT Proteolytic processing regulates key processes in health and disease. The cellular prion protein (PrPC) is subject to at least 3 cleavage events, α-cleavage, β-cleavage and shedding. In contrast to α- and β-cleavage where there is an ongoing controversy on the identity of relevant proteases, the metalloprotease ADAM10 represents the only relevant PrP sheddase. Here we focus on the roles that ADAM10-mediated shedding of PrPC and its pathogenic isoform (PrPSc) might play in regulating their physiological and pathogenic functions, respectively. As revealed by our recent study using conditional ADAM10 knockout mice (Altmeppen et al., 2015), shedding of PrP seems to be involved in key processes of prion diseases. These aspects and several open questions arising from them are discussed. Increased knowledge on this topic can shed new light on prion diseases and other neurodegenerative conditions as well. PMID:26186508

  6. Shedding Light on the Subject.

    ERIC Educational Resources Information Center

    Keller, Brian A.

    1998-01-01

    Presents an activity in which students use mathematical ideas to understand how the intensity of light changes as light passes through water or similar partial barriers, by using a calculator-based laboratory device to record light intensity. Continues with a structured series of questions involving the use of difference equations with which…

  7. Shedding Light on Engineering Design

    ERIC Educational Resources Information Center

    Capobianco, Brenda M.; Nyquist, Chell; Tyrie, Nancy

    2013-01-01

    This article describes the steps incorporated to teach an engineering design process in a fifth-grade science classroom. The engineering design-based activity was an existing scientific inquiry activity using UV light--detecting beads and purposefully creating a series of engineering design-based challenges around the investigation. The…

  8. Shedding Light on Fiber Optics.

    ERIC Educational Resources Information Center

    Bunch, Robert M.

    1994-01-01

    Explains the principles of fiber optics as a medium for light-wave communication. Current uses of fiber systems on college campuses include voice, video, and local area network applications. A group of seven school districts in Minnesota are linked via fiber-optic cables. Other uses are discussed. (MLF)

  9. Algorithmic handwriting analysis of Judah's military correspondence sheds light on composition of biblical texts.

    PubMed

    Faigenbaum-Golovin, Shira; Shaus, Arie; Sober, Barak; Levin, David; Na'aman, Nadav; Sass, Benjamin; Turkel, Eli; Piasetzky, Eli; Finkelstein, Israel

    2016-04-26

    The relationship between the expansion of literacy in Judah and composition of biblical texts has attracted scholarly attention for over a century. Information on this issue can be deduced from Hebrew inscriptions from the final phase of the first Temple period. We report our investigation of 16 inscriptions from the Judahite desert fortress of Arad, dated ca 600 BCE-the eve of Nebuchadnezzar's destruction of Jerusalem. The inquiry is based on new methods for image processing and document analysis, as well as machine learning algorithms. These techniques enable identification of the minimal number of authors in a given group of inscriptions. Our algorithmic analysis, complemented by the textual information, reveals a minimum of six authors within the examined inscriptions. The results indicate that in this remote fort literacy had spread throughout the military hierarchy, down to the quartermaster and probably even below that rank. This implies that an educational infrastructure that could support the composition of literary texts in Judah already existed before the destruction of the first Temple. A similar level of literacy in this area is attested again only 400 y later, ca 200 BCE. PMID:27071103

  10. 2. Light tower, keeper's house and shed, view south southwest, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Light tower, keeper's house and shed, view south southwest, northwest and northeast sides of tower, east and north sides of keeper's house and shed - Whitehead Light Station, Whitehead Island, East northeast of Tenants Harbor, Spruce Head, Knox County, ME

  11. NIH Scientists Shed Light on Mystery Surrounding Hepatitis B Virus

    MedlinePlus

    ... Research 2013 January 2013 (historical) NIH Scientists Shed Light on Mystery Surrounding Hepatitis B Virus Discovery Is ... the University of Oxford, U.K., have shed light on a long-standing enigma about the structure ...

  12. Supercomputing Sheds Light on the Dark Universe

    SciTech Connect

    Salman Habib

    2012-11-15

    At Argonne National Laboratory, scientists are using supercomputers to shed light on one of the great mysteries in science today, the Dark Universe. With Mira, a petascale supercomputer at the Argonne Leadership Computing Facility, a team led by physicists Salman Habib and Katrin Heitmann will run the largest, most complex simulation of the universe ever attempted. By contrasting the results from Mira with state-of-the-art telescope surveys, the scientists hope to gain new insights into the distribution of matter in the universe, advancing future investigations of dark energy and dark matter into a new realm. The team's research was named a finalist for the 2012 Gordon Bell Prize, an award recognizing outstanding achievement in high-performance computing.

  13. Comprehensive analysis of the polygalacturonase and pectin methylesterase genes in Brassica rapa shed light on their different evolutionary patterns.

    PubMed

    Duan, Weike; Huang, Zhinan; Song, Xiaoming; Liu, Tongkun; Liu, Hailong; Hou, Xilin; Li, Ying

    2016-01-01

    Pectins are fundamental polysaccharides in the plant primary cell wall. Polygalacturonases (PGs) and pectin methylesterases (PMEs), major components of the pectin remodeling and disassembly network, are involved in cell separation processes during many stages of plant development. A comprehensive study of these genes in plants could shed light on the evolution patterns of their structural development. In this study, we conducted whole-genome annotation, molecular evolution and gene expression analyses of PGs and PMEs in Brassica rapa and 8 other plant species. A total of 100 PGs and 110 PMEs were identified in B. rapa; they primarily diverged from 12-18 MYA and PMEs were retained more than PGs. Along with another 305 PGs and 348 PMEs in the 8 species, two different expansion or evolution types were discovered: a new branch of class A PGs appeared after the split of gymnosperms and angiosperms, which led to the rapid expansion of PGs; the pro domain was obtained or lost in the proPMEs through comprehensive analyses among PME genes. In addition, the PGs and PMEs exhibit diverged expression patterns. These findings will lead to novel insight regarding functional divergence and conservation in the gene families and provide more support for molecular evolution analyses. PMID:27112365

  14. Comprehensive analysis of the polygalacturonase and pectin methylesterase genes in Brassica rapa shed light on their different evolutionary patterns

    PubMed Central

    Duan, Weike; Huang, Zhinan; Song, Xiaoming; Liu, Tongkun; Liu, Hailong; Hou, Xilin; Li, Ying

    2016-01-01

    Pectins are fundamental polysaccharides in the plant primary cell wall. Polygalacturonases (PGs) and pectin methylesterases (PMEs), major components of the pectin remodeling and disassembly network, are involved in cell separation processes during many stages of plant development. A comprehensive study of these genes in plants could shed light on the evolution patterns of their structural development. In this study, we conducted whole-genome annotation, molecular evolution and gene expression analyses of PGs and PMEs in Brassica rapa and 8 other plant species. A total of 100 PGs and 110 PMEs were identified in B. rapa; they primarily diverged from 12–18 MYA and PMEs were retained more than PGs. Along with another 305 PGs and 348 PMEs in the 8 species, two different expansion or evolution types were discovered: a new branch of class A PGs appeared after the split of gymnosperms and angiosperms, which led to the rapid expansion of PGs; the pro domain was obtained or lost in the proPMEs through comprehensive analyses among PME genes. In addition, the PGs and PMEs exhibit diverged expression patterns. These findings will lead to novel insight regarding functional divergence and conservation in the gene families and provide more support for molecular evolution analyses. PMID:27112365

  15. 1. Shed, railroad, keeper's house, light tower and boathouse, view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Shed, railroad, keeper's house, light tower and boathouse, view southwest, northeast side of shed, keeper's house and tower, east and north sides of boathouse - Seguin Island Light Station, Summit of Seguin Island, south of mouth of Kennebec River, Popham Beach, Sagadahoc County, ME

  16. 2. Shed, railroad, light tower and boathouse, view south southwest, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Shed, railroad, light tower and boathouse, view south southwest, northeast and northwest sides of shed, northeast side of tower, east and north sides of boathouse - Seguin Island Light Station, Summit of Seguin Island, south of mouth of Kennebec River, Popham Beach, Sagadahoc County, ME

  17. 3. Railroad viaduct, keeper's house, light tower and shed, view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Railroad viaduct, keeper's house, light tower and shed, view west, southeast side of viaduct, southeast and northeast sides of keeper's house, tower and shed - Seguin Island Light Station, Summit of Seguin Island, south of mouth of Kennebec River, Popham Beach, Sagadahoc County, ME

  18. 3. Keeper's house, shed, light tower and bell, view east, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Keeper's house, shed, light tower and bell, view east, northwest and southwest sides - Monhegan Island Light Station, Monhegan Island, ten miles south by ferry from Port Clyde, Monhegan, Lincoln County, ME

  19. 1. Keeper's house, shed, covered passageway and light tower, view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Keeper's house, shed, covered passageway and light tower, view northwest, southwest and southeast sides - Monhegan Island Light Station, Monhegan Island, ten miles south by ferry from Port Clyde, Monhegan, Lincoln County, ME

  20. Beat the Winter Blues: Shedding Light on Seasonal Sadness

    MedlinePlus

    ... exit disclaimer . Subscribe Beat the Winter Blues Shedding Light on Seasonal Sadness As the days get shorter, ... clock” responds to cues in your surroundings, especially light and darkness. During the day, your brain sends ...

  1. 5. Shed, keeper's house, boathouse, light tower and oil house, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Shed, keeper's house, boathouse, light tower and oil house, view southeast, northwest and southwest sides - Goat Island Light Station, Goat Island, next to entrance to Cape Porpoise Harbor, just south of Trott Island, Cape Porpoise, York County, ME

  2. Tracking Kids' Eye Movements Might Shed New Light on Autism

    MedlinePlus

    ... Kids' Eye Movements Might Shed New Light on Autism When conversations turn emotional, children with ASD change ... HealthDay News) -- New findings about where children with autism look during conversations could lead to changes in ...

  3. Shedding Some Light on Fluorescent Bulbs.

    ERIC Educational Resources Information Center

    Guilbert, Nicholas R.

    1996-01-01

    Explores some of the principles behind the working of fluorescent bulbs using a specially prepared fluorescent bulb with the white inner fluorescent coating applied along only half its length. Discusses the spectrum, the bulb plasma, and light production. (JRH)

  4. 1. Shed, keeper's house and light tower, view west northwest, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Shed, keeper's house and light tower, view west northwest, south and east sides - Ram Island Light Station, Ram Island, south of Ocean Point & just north of Fisherman Island, marking south side of Fisherman Island Passage, Ocean Point, Lincoln County, ME

  5. Circadian control sheds light on fungal bioluminescence.

    PubMed

    Oliveira, Anderson G; Stevani, Cassius V; Waldenmaier, Hans E; Viviani, Vadim; Emerson, Jillian M; Loros, Jennifer J; Dunlap, Jay C

    2015-03-30

    Bioluminescence, the creation and emission of light by organisms, affords insight into the lives of organisms doing it. Luminous living things are widespread and access diverse mechanisms to generate and control luminescence [1-5]. Among the least studied bioluminescent organisms are phylogenetically rare fungi-only 71 species, all within the ∼ 9,000 fungi of the temperate and tropical Agaricales order-are reported from among ∼ 100,000 described fungal species [6, 7]. All require oxygen [8] and energy (NADH or NADPH) for bioluminescence and are reported to emit green light (λmax 530 nm) continuously, implying a metabolic function for bioluminescence, perhaps as a byproduct of oxidative metabolism in lignin degradation. Here, however, we report that bioluminescence from the mycelium of Neonothopanus gardneri is controlled by a temperature-compensated circadian clock, the result of cycles in content/activity of the luciferase, reductase, and luciferin that comprise the luminescent system. Because regulation implies an adaptive function for bioluminescence, a controversial question for more than two millennia [8-15], we examined interactions between luminescent fungi and insects [16]. Prosthetic acrylic resin "mushrooms," internally illuminated by a green LED emitting light similar to the bioluminescence, attract staphilinid rove beetles (coleopterans), as well as hemipterans (true bugs), dipterans (flies), and hymenopterans (wasps and ants), at numbers far greater than dark control traps. Thus, circadian control may optimize energy use for when bioluminescence is most visible, attracting insects that can in turn help in spore dispersal, thereby benefitting fungi growing under the forest canopy, where wind flow is greatly reduced. PMID:25802150

  6. Circadian Control Sheds Light on Fungal Bioluminescence

    PubMed Central

    Oliveira, Anderson G.; Stevani, Cassius V.; Waldenmaier, Hans E.; Viviani, Vadim; Emerson, Jillian M.; Loros, Jennifer J.; Dunlap, Jay C.

    2015-01-01

    Summary Bioluminescence, the creation and emission of light by organisms, affords insight into the lives of organisms doing it. Luminous living things are widespread and access diverse mechanisms to generate and control luminescence [1-5]. Among the least studied bioluminescent organisms are phylogenetically rare fungi – only 71 species, all within the ~9000 fungi of the temperate and tropical Agaricales Order - are reported from among ~100,000 described fungal species [6,7]. All require oxygen [8] and energy (NADH or NADPH) for bioluminescence, and are reported to emit green light (λmax 530 nm) continuously, implying a metabolic function for bioluminescence, perhaps as a by-product of oxidative metabolism in lignin degradation. Here, however, we report that bioluminescence from the mycelium of Neonothopanus gardneri is controlled by a temperature compensated circadian clock, the result of cycles in content/activity of the luciferase, reductase, and the luciferin that comprise the luminescent system. Because regulation implies an adaptive function for bioluminescence, a controversial question for more than two millenia [8-15], we examined interactions between luminescent fungi and insects [16]. Prosthetic acrylic resin “mushrooms”, internally illuminated by a green LED emitting light similar to the bioluminescence, attract staphilinid rove beetles (coleopterans) as well as hemipterans (true bugs), dipterans (flies), and hymenopterans (wasps and ants) at numbers far greater than dark control traps. Thus, circadian control may optimize energy use for when bioluminescence is most visible, attracting insects that can in turn help in spore dispersal, thereby benefitting fungi growing under the forest canopy where wind flow is greatly reduced. PMID:25802150

  7. Shedding Lyman Alpha Light on Cosmological Reionization

    NASA Astrophysics Data System (ADS)

    Rhoads, James E.; Malhotra, Sangeeta; Ammons, S. Mark; Dressler, Alan; Gonzalez, Alicia; Finkelstein, Steven; Hibon, Pascale; Jiang, Tianxing; Lee, Janice; Mobasher, Bahram; Monson, Andy; Persson, S. Eric; Probst, Ronald; Swaters, Rob; Tilvi, Vithal S.; Veilleux, Sylvain; Wang, Junxian; Zabludoff, Ann; Zheng, Zhenya

    2015-08-01

    Lyman alpha photons are a powerful tool for studying reionization. They interact strongly with neutral hydrogen, so that neutral intergalactic gas acts to hide Lyman alpha light from our instruments. I will discuss two ongoing narrowband surveys to study the Epoch of Reionization. The Deep And Wide Narrowband (DAWN) survey is a 40 night NOAO survey program to look for Lyman alpha emission at redshift 7.7, using the NEWFIRM camera on the 4m Mayall Telescope at Kitt Peak National Observatory. The First Light And Reionization Experiment (FLARE) is pursuing a corresponding survey at redshift 8.8, using the FourStar camera on the Magellan telescope. Both surveys are motivated by the application of Lyman alpha lines to the study of reionization. Reionization marked the first global impact that gravitationally bound objects (stars and/or black holes) had on the universe around them, and also the last time that most hydrogen atoms did anything noteworthy. I will present results from both the DAWN and FLARE surveys, which have identified candidate galaxies near redshifts 7.7 and 8.8 in multiple fields.

  8. Shedding New Light on Retinal Protein Photochemistry

    NASA Astrophysics Data System (ADS)

    Wand, Amir; Gdor, Itay; Zhu, Jingyi; Sheves, Mordechai; Ruhman, Sanford

    2013-04-01

    The ultrafast spectroscopic investigation of novel retinal proteins challenges existing notions concerning the course of primary events in these natural photoreceptors. We review two illustrations here. The first demonstrates that changes in the initial retinal configuration can alter the duration of photochemistry by nearly an order of magnitude in Anabaena sensory rhodopsin, making it as rapid as the ballistic photoisomerization in visual pigments. This prompted a reinvestigation of the much studied bacteriorhodopsin, leading to a similar trend as well, contrary to earlier reports. The second involves the study of xanthorhodopsin, an archaeal proton pump that includes an attached light-harvesting carotenoid. Pump-probe experiments demonstrate the efficient transfer of energy from carotenoid to retinal, providing a first glimpse at a cooperative multichromophore function, which is probably characteristic of many other proteins as well. Finally, we discuss measures required to advance our knowledge from kinetics to mode-specific dynamics concerning this expanding family of biological photoreceptors.

  9. Shedding New Light on Early Caries Detection

    PubMed Central

    Choo-Smith, Lin-P'ing; Dong, Cecilia C.S.; Cleghorn, Blaine; Hewko, Mark

    2009-01-01

    Dental caries continues to be a common chronic disease among various population groups. Patient care can be improved with detection at the earliest stage. However, current techniques do not have sufficient sensitivity and specificity. We discuss 2 new methods — optical coherence tomography (OCT) and polarized Raman spectroscopy (PRS) — that are potentially useful for early caries detection and monitoring. OCT produces morphologic depth images of near-surface tissue structures with a resolution that is an order of magnitude greater than ultrasound imaging. Based on measurement of back-scattered near infrared light, OCT shows that sound enamel causes high-intensity back-scattering at the tooth surface that decreases rapidly with depth. In contrast, incipient lesions cause higher light back-scattering at the tooth surface and subsurface scattering indicative of porosity caused by demineralization. The scatter region within the enamel correlates well with the classical triangular shape of subsurface lesions observed in histologic sections. OCT imaging not only allows identification of incipient lesions, but also provides information on surface integrity and lesion depth. PRS furnishes biochemical information about the tooth's composition, mineral content and crystallinity. The depolarization ratio derived from the dominant phosphate peak of hydroxyapatite in sound teeth is consistently lower than that from incipient caries. This difference is attributed to the change in enamel crystallite morphology or orientation that occurs with acid demineralization. Thus, PRS can be used to confirm suspect lesions determined by OCT and rule out false-positive signals from non-carious anomalies. The combination of OCT and PRS provides a new detection method with high sensitivity and specificity that will improve caries management and patient care. Future studies are aimed at developing intraoral probes to validate the findings in vivo. PMID:19126361

  10. Shedding Light on the Cosmic Skeleton

    NASA Astrophysics Data System (ADS)

    2009-11-01

    Astronomers have tracked down a gigantic, previously unknown assembly of galaxies located almost seven billion light-years away from us. The discovery, made possible by combining two of the most powerful ground-based telescopes in the world, is the first observation of such a prominent galaxy structure in the distant Universe, providing further insight into the cosmic web and how it formed. "Matter is not distributed uniformly in the Universe," says Masayuki Tanaka from ESO, who led the new study. "In our cosmic vicinity, stars form in galaxies and galaxies usually form groups and clusters of galaxies. The most widely accepted cosmological theories predict that matter also clumps on a larger scale in the so-called 'cosmic web', in which galaxies, embedded in filaments stretching between voids, create a gigantic wispy structure." These filaments are millions of light years long and constitute the skeleton of the Universe: galaxies gather around them, and immense galaxy clusters form at their intersections, lurking like giant spiders waiting for more matter to digest. Scientists are struggling to determine how they swirl into existence. Although massive filamentary structures have been often observed at relatively small distances from us, solid proof of their existence in the more distant Universe has been lacking until now. The team led by Tanaka discovered a large structure around a distant cluster of galaxies in images they obtained earlier. They have now used two major ground-based telescopes to study this structure in greater detail, measuring the distances from Earth of over 150 galaxies, and, hence, obtaining a three-dimensional view of the structure. The spectroscopic observations were performed using the VIMOS instrument on ESO's Very Large Telescope and FOCAS on the Subaru Telescope, operated by the National Astronomical Observatory of Japan. Thanks to these and other observations, the astronomers were able to make a real demographic study of this structure

  11. Expression analysis in response to drought stress in soybean: Shedding light on the regulation of metabolic pathway genes.

    PubMed

    Guimarães-Dias, Fábia; Neves-Borges, Anna Cristina; Viana, Antonio Americo Barbosa; Mesquita, Rosilene Oliveira; Romano, Eduardo; de Fátima Grossi-de-Sá, Maria; Nepomuceno, Alexandre Lima; Loureiro, Marcelo Ehlers; Alves-Ferreira, Márcio

    2012-06-01

    Metabolomics analysis of wild type Arabidopsis thaliana plants, under control and drought stress conditions revealed several metabolic pathways that are induced under water deficit. The metabolic response to drought stress is also associated with ABA dependent and independent pathways, allowing a better understanding of the molecular mechanisms in this model plant. Through combining an in silico approach and gene expression analysis by quantitative real-time PCR, the present work aims at identifying genes of soybean metabolic pathways potentially associated with water deficit. Digital expression patterns of Arabidopsis genes, which were selected based on the basis of literature reports, were evaluated under drought stress condition by Genevestigator. Genes that showed strong induction under drought stress were selected and used as bait to identify orthologs in the soybean genome. This allowed us to select 354 genes of putative soybean orthologs of 79 Arabidopsis genes belonging to 38 distinct metabolic pathways. The expression pattern of the selected genes was verified in the subtractive libraries available in the GENOSOJA project. Subsequently, 13 genes from different metabolic pathways were selected for validation by qPCR experiments. The expression of six genes was validated in plants undergoing drought stress in both pot-based and hydroponic cultivation systems. The results suggest that the metabolic response to drought stress is conserved in Arabidopsis and soybean plants. PMID:22802708

  12. Expression analysis in response to drought stress in soybean: Shedding light on the regulation of metabolic pathway genes

    PubMed Central

    Guimarães-Dias, Fábia; Neves-Borges, Anna Cristina; Viana, Antonio Americo Barbosa; Mesquita, Rosilene Oliveira; Romano, Eduardo; de Fátima Grossi-de-Sá, Maria; Nepomuceno, Alexandre Lima; Loureiro, Marcelo Ehlers; Alves-Ferreira, Márcio

    2012-01-01

    Metabolomics analysis of wild type Arabidopsis thaliana plants, under control and drought stress conditions revealed several metabolic pathways that are induced under water deficit. The metabolic response to drought stress is also associated with ABA dependent and independent pathways, allowing a better understanding of the molecular mechanisms in this model plant. Through combining an in silico approach and gene expression analysis by quantitative real-time PCR, the present work aims at identifying genes of soybean metabolic pathways potentially associated with water deficit. Digital expression patterns of Arabidopsis genes, which were selected based on the basis of literature reports, were evaluated under drought stress condition by Genevestigator. Genes that showed strong induction under drought stress were selected and used as bait to identify orthologs in the soybean genome. This allowed us to select 354 genes of putative soybean orthologs of 79 Arabidopsis genes belonging to 38 distinct metabolic pathways. The expression pattern of the selected genes was verified in the subtractive libraries available in the GENOSOJA project. Subsequently, 13 genes from different metabolic pathways were selected for validation by qPCR experiments. The expression of six genes was validated in plants undergoing drought stress in both pot-based and hydroponic cultivation systems. The results suggest that the metabolic response to drought stress is conserved in Arabidopsis and soybean plants. PMID:22802708

  13. Shedding Light on the Pulsar Wind

    NASA Astrophysics Data System (ADS)

    Khangulyan, Dmitry; Aharonian, Felix; Bogovalov, Sergey V.

    2012-07-01

    Pulsars are believed to eject ultrarelativistic electron-positron winds that propagate to the large distances leading to the formation of the extended non-thermal sources known as plerions. The wind has been proposed to originate close to the light cylinder, and carry the rotational energy losses of the pulsar. At the beginning the wind is dominated by electromagnetic energy (Poynting flux), but at some later stage the wind is accelerated with most of the Poynting flux being converted to the kinetic energy of bulk motion. Such winds have not been yet observed, therefore the proposed scenario has been deemed inconclusive. The `cold' winds (in the sense of the low energy of the electrons in the frame of moving plasma) represent a form of "dark substance" since, despite the very high energy of the wind particles, the wind emission is extremely weak. In fact, the pulsar winds are visible only in inverse Compton gamma-rays. Recent observations in high energy (HE) and very high energy (VHE) domains with Fermi Large Area Telescope (Fermi/LAT) and ground based Cherenkov detectors Magic and Veritas allow the key properties of the pulsar winds to be measured in a few important systems.

  14. Flashes Shed Light on Cosmic Clashes

    NASA Astrophysics Data System (ADS)

    2005-10-01

    An international team of astronomers led by Danish astronomer Jens Hjorth [1] has for the first time observed the visible light from a short gamma-ray burst (GRB). Using the 1.5m Danish telescope at La Silla (Chile), they showed that these short, intense bursts of gamma-ray emission most likely originate from the violent collision of two merging neutron stars. The same team has also used ESO's Very Large Telescope to constrain the birthplace of the first ever short burst whose position could be pinpointed with high precision, GRB 050509B. The results are being published in the October 6 issue of the journal Nature. Gamma-ray bursts, the most powerful type of explosion known in the Universe, have been a mystery for three decades. They come in two different flavours, long and short ones. Over the past few years, international efforts have convincingly shown that long gamma-ray bursts are linked with the ultimate explosion of massive stars (hypernovae; see e.g. ESO PR 16/03). "The breakthrough in our understanding of long-duration GRBs (those lasting more than about 2 seconds), which ultimately linked them with the energetic explosion of a massive star as it collapses into a black hole, came from the discovery of their long-lived X-ray and optical afterglows," says Jens Hjorth (Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Denmark). "Short duration GRBs have however evaded optical detection for more than 30 years," he adds. Things changed recently. In the night of July 9 to 10, 2005, the NASA HETE-2 satellite detected a burst of only 70-millisecond duration and, based on the detection of X-rays, was able to determine its position in the sky. Thirty-three hours after, Jens Hjorth and his team obtained images of this region of the sky using the Danish 1.5m telescope at ESO La Silla. The images showed the presence of a fading source, sitting on the edge of a galaxy. "We have thus discovered the first optical afterglow of a short gamma-ray burst

  15. Population shift of binding pocket size and dynamic correlation analysis shed new light on the anticooperative mechanism of PII protein

    PubMed Central

    Ma, Cheng-Wei; Lüddecke, Jan; Forchhammer, Karl; Zeng, An-Ping

    2014-01-01

    PII protein is one of the largest families of signal transduction proteins in archaea, bacteria, and plants, controlling key processes of nitrogen assimilation. An intriguing characteristic for many PII proteins is that the three ligand binding sites exhibit anticooperative allosteric regulation. In this work, PII protein from Synechococcus elongatus, a model for cyanobacteria and plant PII proteins, is utilized to reveal the anticooperative mechanism upon binding of 2-oxoglutarate (2-OG). To this end, a method is proposed to define the binding pocket size by identifying residues that contribute greatly to the binding of 2-OG. It is found that the anticooperativity is realized through population shift of the binding pocket size in an asymmetric manner. Furthermore, a new algorithm based on the dynamic correlation analysis is developed and utilized to discover residues that mediate the anticooperative process with high probability. It is surprising to find that the T-loop, which is believed to be responsible for mediating the binding of PII with its target proteins, also takes part in the intersubunit signal transduction process. Experimental results of PII variants further confirmed the influence of T-loop on the anticooperative regulation, especially on binding of the third 2-OG. These discoveries extend our understanding of the PII T-loop from being essential in versatile binding of target protein to signal-mediating in the anticooperative allosteric regulation. Proteins 2014; 82:1048–1059. PMID:24218085

  16. Comprehensive Phylogenetic Analysis Sheds Light on the Diversity and Origin of the MLO Family of Integral Membrane Proteins

    PubMed Central

    Kusch, Stefan; Pesch, Lina; Panstruga, Ralph

    2016-01-01

    Mildew resistance Locus O (MLO) proteins are polytopic integral membrane proteins that have long been considered as plant-specific and being primarily involved in plant–powdery mildew interactions. However, research in the past decade has revealed that MLO proteins diverged into a family with several clades whose members are associated with different physiological processes. We provide a largely increased dataset of MLO amino acid sequences, comprising nearly all major land plant lineages. Based on this comprehensive dataset, we defined seven phylogenetic clades and reconstructed the likely evolution of the MLO family in embryophytes. We further identified several MLO peptide motifs that are either conserved in all MLO proteins or confined to one or several clades, supporting the notion that clade-specific diversification of MLO functions is associated with particular sequence motifs. In baker’s yeast, some of these motifs are functionally linked to transmembrane (TM) transport of organic molecules and ions. In addition, we attempted to define the evolutionary origin of the MLO family and found that MLO-like proteins with highly diverse membrane topologies are present in green algae, but also in the distinctly related red algae (Rhodophyta), Amoebozoa, and Chromalveolata. Finally, we discovered several instances of putative fusion events between MLO proteins and different kinds of proteins. Such Rosetta stone-type hybrid proteins might be instructive for future analysis of potential MLO functions. Our findings suggest that MLO is an ancient protein that possibly evolved in unicellular photosynthetic eukaryotes, and consolidated in land plants with a conserved topology, comprising seven TM domains and an intrinsically unstructured C-terminus. PMID:26893454

  17. Comprehensive Phylogenetic Analysis Sheds Light on the Diversity and Origin of the MLO Family of Integral Membrane Proteins.

    PubMed

    Kusch, Stefan; Pesch, Lina; Panstruga, Ralph

    2016-03-01

    Mildew resistanceLocusO(MLO) proteins are polytopic integral membrane proteins that have long been considered as plant-specific and being primarily involved in plant-powdery mildew interactions. However, research in the past decade has revealed that MLO proteins diverged into a family with several clades whose members are associated with different physiological processes. We provide a largely increased dataset of MLO amino acid sequences, comprising nearly all major land plant lineages. Based on this comprehensive dataset, we defined seven phylogenetic clades and reconstructed the likely evolution of the MLO family in embryophytes. We further identified several MLO peptide motifs that are either conserved in all MLO proteins or confined to one or several clades, supporting the notion that clade-specific diversification of MLO functions is associated with particular sequence motifs. In baker's yeast, some of these motifs are functionally linked to transmembrane (TM) transport of organic molecules and ions. In addition, we attempted to define the evolutionary origin of the MLO family and found that MLO-like proteins with highly diverse membrane topologies are present in green algae, but also in the distinctly related red algae (Rhodophyta), Amoebozoa, and Chromalveolata. Finally, we discovered several instances of putative fusion events between MLO proteins and different kinds of proteins. Such Rosetta stone-type hybrid proteins might be instructive for future analysis of potential MLO functions. Our findings suggest that MLO is an ancient protein that possibly evolved in unicellular photosynthetic eukaryotes, and consolidated in land plants with a conserved topology, comprising seven TM domains and an intrinsically unstructured C-terminus. PMID:26893454

  18. Shedding light on Aspergillus niger volatile exometabolome

    PubMed Central

    Costa, Carina Pedrosa; Gonçalves Silva, Diogo; Rudnitskaya, Alisa; Almeida, Adelaide; Rocha, Sílvia M.

    2016-01-01

    An in-depth exploration of the headspace content of Aspergillus niger cultures was performed upon different growth conditions, using a methodology based on advanced multidimensional gas chromatography. This volatile fraction comprises 428 putatively identified compounds distributed over several chemical families, being the major ones hydrocarbons, alcohols, esters, ketones and aldehydes. These metabolites may be related with different metabolic pathways, such as amino acid metabolism, biosynthesis and metabolism of fatty acids, degradation of aromatic compounds, mono and sesquiterpenoid synthesis and carotenoid cleavage. The A. niger molecular biomarkers pattern was established, comprising the 44 metabolites present in all studied conditions. This pattern was successfully used to distinguish A. niger from other fungi (Candida albicans and Penicillium chrysogenum) with 3 days of growth by using Partial Least Squares-Discriminant Analysis (PLS-DA). In addition, PLS-DA-Variable Importance in Projection was applied to highlight the metabolites playing major roles in fungi distinction; decreasing the initial dataset to only 16 metabolites. The data pre-processing time was substantially reduced, and an improvement of quality-of-fit value was achieved. This study goes a step further on A. niger metabolome construction and A. niger future detection may be proposed based on this molecular biomarkers pattern. PMID:27264696

  19. Shedding light on Aspergillus niger volatile exometabolome.

    PubMed

    Costa, Carina Pedrosa; Gonçalves Silva, Diogo; Rudnitskaya, Alisa; Almeida, Adelaide; Rocha, Sílvia M

    2016-01-01

    An in-depth exploration of the headspace content of Aspergillus niger cultures was performed upon different growth conditions, using a methodology based on advanced multidimensional gas chromatography. This volatile fraction comprises 428 putatively identified compounds distributed over several chemical families, being the major ones hydrocarbons, alcohols, esters, ketones and aldehydes. These metabolites may be related with different metabolic pathways, such as amino acid metabolism, biosynthesis and metabolism of fatty acids, degradation of aromatic compounds, mono and sesquiterpenoid synthesis and carotenoid cleavage. The A. niger molecular biomarkers pattern was established, comprising the 44 metabolites present in all studied conditions. This pattern was successfully used to distinguish A. niger from other fungi (Candida albicans and Penicillium chrysogenum) with 3 days of growth by using Partial Least Squares-Discriminant Analysis (PLS-DA). In addition, PLS-DA-Variable Importance in Projection was applied to highlight the metabolites playing major roles in fungi distinction; decreasing the initial dataset to only 16 metabolites. The data pre-processing time was substantially reduced, and an improvement of quality-of-fit value was achieved. This study goes a step further on A. niger metabolome construction and A. niger future detection may be proposed based on this molecular biomarkers pattern. PMID:27264696

  20. Shedding Light on Restoring Respiratory Function After Spinal Cord Injury

    PubMed Central

    Alilain, Warren J.; Silver, Jerry

    2009-01-01

    Loss of respiratory function is one of the leading causes of death following spinal cord injury. Because of this, much work has been done in studying ways to restore respiratory function following spinal cord injury (SCI) – including pharmacological and regeneration strategies. With the emergence of new and powerful tools from molecular neuroscience, new therapeutically relevant alternatives to these approaches have become available, including expression of light sensitive proteins called channelrhodopsins. In this article we briefly review the history of various attempts to restore breathing after C2 hemisection, and focus on our recent work using the activation of light sensitive channels to restore respiratory function after experimental SCI. We also discuss how such light-induced activity can help shed light on the inner workings of the central nervous system respiratory circuitry that controls diaphragmatic function. PMID:19893756

  1. PHAROS: Shedding Light on the Near-Earth Asteroid Apophis

    NASA Technical Reports Server (NTRS)

    Sharma, Jonathan; Lafleur, Jarret; Barron, Kreston; Townley, Jonathan; Shah, Nilesh; Apa, Jillian

    2007-01-01

    The Pharos mission to asteroid Apophis provides the first major opportunity to enhance orbital state and scientific knowledge of the most threatening Earth-crossing asteroid that has ever been tracked. Pharos aims to accomplish concrete and feasible orbit determination and scientific objectives while achieving balance among mission cost, nsk,and schedule. Similar to its ancient Egyptian namesake, Pharos acts as a beacon shedding light not only on the physical characteristics of Apophis, but also on its state as it travels through the solar system.

  2. Shedding Light on Light Pollution: Reports from GLOBE at Night

    NASA Astrophysics Data System (ADS)

    Walker, Constance E.; Pompea, S. M.; Isbell, D.

    2009-05-01

    The citizen-science program on light pollution, GLOBE at Night, has had rich responses during this year's campaign in March 2009. Reporting on some of the highlights, we will hear success stories and lessons learned from educators, students, science centers and astronomy clubs from around the world. Communities will be featured from several cities, such Norman, Oklahoma, Mishawaka, Indiana, Willimantic, Connecticut, and Waynesville, Ohio, which created mini-campaigns that combined local students with public advocates and representatives from local city and county governments. Connecticut kids collaborated with students in Wales, Canada and Romania on GLOBE at Night, and an extensive campaign was planned with the schools near the observatories of north-central Chile. Groups that have received special training in GLOBE at Night and related activities include the "Astronomy from the Ground Up” network of science and nature centers (fostered by the ASP and the NSF), 146 amateur astronomers who are part of the ASP-NASA Night-Sky Network, and the Association of Science-Technology Centers. Special training was given over forums, telecon-powerpoint presentations and blogs, to fit the needs of the communities. Among the more interesting media efforts for the general public, GLOBE at Night was the topic of the March 6 episode of the IYA2009 "Days of Astronomy" podcast. International organizing efforts for GLOBE at Night have been strong in countries like Argentina, Australia, Austria, Brazil, Canada, Chile, Costa Rica, the Czech Republic, Germany, Hungary, Ireland, Poland, Portugal, Romania, Spain and the United Kingdom, to name a few. We will also discuss how cities, such as Tucson, Arizona, combined efforts on GLOBE at Night with involvement in the World Wildlife Fund's Earth Hour event (www.earthhour.org). Earth Hour encouraged everyone to turn out their lights from 8:30-9:30 p.m. local time on Saturday, March 28, the final night of GLOBE at Night 2009.

  3. Necroptosis in acute kidney injury: a shedding light

    PubMed Central

    Wang, S; Zhang, C; Hu, L; Yang, C

    2016-01-01

    Acute kidney injury (AKI) is a common and severe clinical condition with a heavy healthy burden around the world. In spite of supportive therapies, the mortality associated with AKI remains high. Our limited understanding of the complex cell death mechanism in the process of AKI impedes the development of desirable therapeutics. Necroptosis is a recently identified novel form of cell death contributing to numerable diseases and tissue damages. Increasing evidence has suggested that necroptosis has an important role in the pathogenesis of various types of AKI. Therefore, we present here the signaling pathways and main regulators of necroptosis that are potential candidate for therapeutic strategies. Moreover, we emphasize on the potential role and corresponding mechanisms of necroptosis in AKI based on recent advances, and also discuss the possible therapeutic regimens based on manipulating necroptosis. Taken together, the progress in this field sheds new light into the prevention and management of AKI in clinical practice. PMID:26938298

  4. Butterfly genomics sheds light on the process of hybrid speciation.

    PubMed

    Nadeau, Nicola

    2014-09-01

    How common is hybridization between species and what effect does it have on the evolutionary process? Can hybridization generate new species and what indeed is a species? In this issue, Gompert et al. (2014) show how massive, genome-scale data sets can be used to shed light on these questions. They focus on the Lycaeides butterflies, and in particular, several populations from the western USA, which have characteristics suggesting that they may contain hybrids of two or more different species (Gompert et al. 2006). They demonstrate that these populations do contain mosaic genomes made up of components from different parental species. However, this appears to have been largely driven by historical admixture, with more recent processes appearing to be isolating the populations from each other. Therefore, these populations are on their way to becoming distinct species (if they are not already) but have arisen following extensive hybridization between other distinct populations or species (Fig. 1). PMID:25208505

  5. Shedding Light on Thirteen Years of Darkness: Content Analysis of Articles Pertaining to Transgender Issues in Marriage/Couple and Family Therapy Journals

    ERIC Educational Resources Information Center

    Blumer, Markie L. C.; Green, Mary S.; Knowles, Sarah J.; Williams, April

    2012-01-01

    What is the extent to which marriage/couple and family therapy (M/CFT) journals address transgender issues and how many of them say they are inclusive of transgender persons when they are not? To answer these queries, a content analysis was conducted on articles published in M/CFT literature from 1997 through 2009. Of the 10,739 articles examined…

  6. In-depth analysis of secretome and N-glycosecretome of human hepatocellular carcinoma metastatic cell lines shed light on metastasis correlated proteins

    PubMed Central

    Li, Xianyu; Jiang, Jing; Zhao, Xinyuan; Zhao, Yan; Cao, Qichen; Zhao, Qing; Han, Huanhuan; Wang, Jifeng; Yu, Zixiang; Peng, Bo; Ying, Wantao; Qian, Xiaohong

    2016-01-01

    Cancer cell metastasis is a major cause of cancer fatality. But the underlying molecular mechanisms remain incompletely understood, which results in the lack of efficient diagnosis, therapy and prevention approaches. Here, we report a systematic study on the secretory proteins (secretome) and secretory N-glycoproteins (N-glycosecretome) of four human hepatocellular carcinoma (HCC) cell lines with different metastatic potential, to explore the molecular mechanism of metastasis and supply the clues for effective measurement of diagnosis and therapy. Totally, 6242 unique gene products (GPs) and 1637 unique N-glycosites from 635 GPs were confidently identified. About 4000 GPs on average were quantified in each of the cell lines, 1156 of which show differential expression (p<0.05). Ninety-nine percentage of the significantly altered proteins were secretory proteins and proteins correlated to cell movement were significantly activated with the increasing of metastatic potential of the cell lines. Twenty-three GPs increased both in the secretome and the N-glycosecretome were chosen as candidates and verified by western blot analysis, and 10 of them were chosen for immunohistochemistry (IHC) analysis. The cumulative survival rates of the patients with candidate (FAT1, DKK3) suggested that these proteins might be used as biomarkers for HCC diagnosis. In addition, a comparative analysis with the published core human plasma database (1754 GPs) revealed that there were 182 proteins not presented in the human plasma database but identified by our studies, some of which were selected and verified successfully by western blotting in human plasma. PMID:27014972

  7. In-depth analysis of secretome and N-glycosecretome of human hepatocellular carcinoma metastatic cell lines shed light on metastasis correlated proteins.

    PubMed

    Li, Xianyu; Jiang, Jing; Zhao, Xinyuan; Zhao, Yan; Cao, Qichen; Zhao, Qing; Han, Huanhuan; Wang, Jifeng; Yu, Zixiang; Peng, Bo; Ying, Wantao; Qian, Xiaohong

    2016-04-19

    Cancer cell metastasis is a major cause of cancer fatality. But the underlying molecular mechanisms remain incompletely understood, which results in the lack of efficient diagnosis, therapy and prevention approaches. Here, we report a systematic study on the secretory proteins (secretome) and secretory N-glycoproteins (N-glycosecretome) of four human hepatocellular carcinoma (HCC) cell lines with different metastatic potential, to explore the molecular mechanism of metastasis and supply the clues for effective measurement of diagnosis and therapy. Totally, 6242 unique gene products (GPs) and 1637 unique N-glycosites from 635 GPs were confidently identified. About 4000 GPs on average were quantified in each of the cell lines, 1156 of which show differential expression (p<0.05). Ninety-nine percentage of the significantly altered proteins were secretory proteins and proteins correlated to cell movement were significantly activated with the increasing of metastatic potential of the cell lines. Twenty-three GPs increased both in the secretome and the N-glycosecretome were chosen as candidates and verified by western blot analysis, and 10 of them were chosen for immunohistochemistry (IHC) analysis. The cumulative survival rates of the patients with candidate (FAT1, DKK3) suggested that these proteins might be used as biomarkers for HCC diagnosis. In addition, a comparative analysis with the published core human plasma database (1754 GPs) revealed that there were 182 proteins not presented in the human plasma database but identified by our studies, some of which were selected and verified successfully by western blotting in human plasma. PMID:27014972

  8. The Enrichment of Histomonas meleagridis and Its Pathogen-Specific Protein Analysis: A First Step to Shed Light on Its Virulence.

    PubMed

    Pham, Anh Dao Nguyen; Mast, Jan; Magez, Stefan; Goddeeris, Bruno Maria; Carpentier, Sebastien C

    2016-09-01

    Since the discovery of Histomonas meleagridis in 1893, the necessity of isolating pure H. meleagridis has been highlighted over the years in the battle against histomonosis. Insights into the molecular characteristics of this protozoon open possibilities to proper treatment. Axenization of H. meleagridis in vitro cultures cocultured with bacteria has been unsuccessful. Numerous unsuccessful attempts at culturing H. meleagridis axenically have reinforced the assumption that the protozoa had an obligate relationship with certain bacteria originating from the host ceca. Within these perspectives, we enriched H. meleagridis cells from a mono-eukaryotic culture copropagated with host cecal bacteria by flow cytometry. The enrichment of histomonads was confirmed through transmission electron microscopy and two-dimensional gel electrophoresis. For the first time several protein spots were successfully identified. The majority of spots were annotated as cytoskeletal proteins. Actin microfilaments are known to be a key player in cell spreading, cell adhesion, phagocytosis, signal transduction, and several other processes. Together with the identification of superoxide dismutase, the information generated from protein analysis of H. meleagridis may serve as a very first step toward understanding its pathogenesis and virulence. PMID:27610722

  9. Melanopsin--shedding light on the elusive circadian photopigment.

    PubMed

    Brown, R Lane; Robinson, Phyllis R

    2004-03-01

    Circadian photoentrainment is the process by which the brain's internal clock becomes synchronized with the daily external cycle of light and dark. In mammals, this process is mediated exclusively by a novel class of retinal ganglion cells that send axonal projections to the suprachiasmatic nuclei (SCN), the region of the brain that houses the circadian pacemaker. In contrast to their counterparts that mediate image-forming vision, SCN-projecting RGCs are intrinsically sensitive to light, independent of synaptic input from rod and cone photoreceptors. The recent discovery of these photosensitive RGCs has challenged the long-standing dogma of retinal physiology that rod and cone photoreceptors are the only retinal cells that respond directly to light and has explained the perplexing finding that mice lacking rod and cone photoreceptors can still reliably entrain their circadian rhythms to light. These SCN-projecting RGCs selectively express melanopsin, a novel opsin-like protein that has been proposed as a likely candidate for the photopigment in these cells. Research in the past three years has revealed that disruption of the melanopsin gene impairs circadian photo- entrainment, as well as other nonvisual responses to light such as the pupillary light reflex. Until recently, however, there was no direct demonstration that melanopsin formed a functional photopigment capable of catalyzing G-protein activation in a light-dependent manner. Our laboratory has recently succeeded in expressing melanopsin in a heterologous tissue culture system and reconstituting a pigment with the 11-cis-retinal chromophore. In a reconstituted biochemical system, the reconstituted melanopsin was capable of activating transducin, the G-protein of rod photoreceptors, in a light-dependent manner. The absorbance spectrum of this heterologously expressed melanopsin, however, does not match that predicted by previous behavioral and electophysiological studies. Although melanopsin is clearly the

  10. UVC Sheds New Light on School Mold Problems.

    ERIC Educational Resources Information Center

    Freeman, James

    2002-01-01

    Describes how the LaPorte Independent School District in Texas turned to ultraviolent light devices installed within the HVAC system to combat mold and fungus after conventional approaches failed. Describes the additional benefits of energy savings from the system. (EV)

  11. Reflectives: Phosphors and lasers - shedding light on rare earths

    SciTech Connect

    Tonneson, L.C.; Fox, G.J.

    1996-04-01

    The first powder electroluminescent phosphor was introduced in 1936. Today, phosphors, particularly those made of high-purity rare earths, have found their way into a variety of products: industrial, commercial, and consumer, alike. The fluorescent lamp industry which remains the leading market for the use of high-purity rare earths, lit the way for the future of rare earths in the optical, x-ray, and display screen applications. Light combined with rare earth materials is also a successful recipe for reflectivity needed in filtering applications such as optics, lasers, and conductors. This article discusses the applications and markets for phosphors and rare earths.

  12. Shedding Light on Astronomy Textbooks for Astro 101

    NASA Astrophysics Data System (ADS)

    Urban, Andrea; Silge, Julia D.

    2015-01-01

    Astronomy textbooks present new vocabulary and concepts to students in different and unique ways. Understanding the differences between textbooks is useful for confirming that the textbook you use in your class is the best possible match for how you teach astronomy. We compare the treatment of terms and equations dealing with the Sun and properties of light in over ten different introductory textbooks. For example, nearly every textbook uses a different equation for angular resolution. (Come by the poster to vote for your favorite!) There are also various forms of the equation for Wien's Law and different uses of the terms 'hydrostatic equilibrium' and 'blackbody radiation.' We discuss possible reasons for the approximations and simplifications made by textbook authors.

  13. Shedding light on azopolymer brush dynamics by fluorescence correlation spectroscopy.

    PubMed

    Kollarigowda, R H; De Santo, I; Rianna, C; Fedele, C; Manikas, A C; Cavalli, S; Netti, P A

    2016-09-14

    Understanding the response to illumination at a molecular level as well as characterising polymer brush dynamics are key features that guide the engineering of new light-stimuli responsive materials. Here, we report on the use of a confocal microscopy technique that was exploited to discern how a single molecular event such as the photoinduced isomerisation of azobenzene can affect an entire polymeric material at a macroscopic level leading to photodriven mass-migration. For this reason, a set of polymer brushes, containing azobenzene (Disperse Red 1, DR) on the side chains of poly(methacrylic acid), was synthesised and the influence of DR on the polymer brush dynamics was investigated for the first time by Fluorescence Correlation Spectroscopy (FCS). Briefly, two dynamics were observed, a short one coming from the isomerisation of DR and a long one related to the brush main chain. Interestingly, photoinduced polymer aggregation in the confocal volume was observed. PMID:27491890

  14. Shedding light on proteins, nucleic acids, cells, humans and fish.

    PubMed

    Setlow, Richard B

    2002-03-01

    I was trained as a physicist in graduate school. Hence, when I decided to go into the field of biophysics, it was natural that I concentrated on the effects of light on relatively simple biological systems, such as proteins. The wavelengths absorbed by the amino acid subunits of proteins are in the ultraviolet (UV). The wavelengths that affect the biological activities, the action spectra, also are in the UV, but are not necessarily parallel to the absorption spectra. Understanding these differences led me to investigate the action spectra for affecting nucleic acids, and the effects of UV on viruses and cells. The latter studies led me to the discovery of the important molecular nature of the damages affecting DNA (cyclobutane pyrimidine dimers) and to the discovery of nucleotide excision repair. Individuals with the genetic disease xeroderma pigmentosum (XP) are extraordinarily sensitive to sunlight-induced skin cancer. The finding, by James Cleaver, that their skin cells were defective in DNA repair strongly suggested that DNA damage was a key step in carcinogenesis. Such information was important for estimating the wavelengths in sunlight responsible for human skin cancer and for predicting the effects of ozone depletion on the incidence of non-melanoma skin cancer. It took experiments with backcross hybrid fish to call attention to the probable role of the longer UV wavelengths not absorbed by DNA in the induction of melanoma. These reflections trace the biophysicist's path from molecules to melanoma. PMID:11906839

  15. Shedding light on neutrino masses with dark forces

    NASA Astrophysics Data System (ADS)

    Batell, Brian; Pospelov, Maxim; Shuve, Brian

    2016-08-01

    Heavy right-handed neutrinos, N , provide the simplest explanation for the origin of light neutrino masses and mixings. If M N is at or below the weak scale, direct experimental discovery of these states is possible at accelerator experiments such as the LHC or new dedicated beam dump experiments; in these experiments, N decays after traversing a macroscopic distance from the collision point. The experimental sensitivity to right-handed neutrinos is significantly enhanced if there is a new "dark" gauge force connecting them to the Standard Model (SM), and detection of N can be the primary discovery mode for the new dark force itself. We take the well-motivated example of a B - L gauge symmetry and analyze the sensitivity to displaced decays of N produced via the new gauge interaction in two experiments: the LHC and the proposed SHiP beam dump experiment. In the most favorable case in which the mediator can be produced on-shell and decays to right handed neutrinos ( pp → X + V B- L → X + N N ), the sensitivity reach is controlled by the square of the B - L gauge coupling. We demonstrate that these experiments could access neutrino parameters responsible for the observed SM neutrino masses and mixings in the most straightforward implementation of the see-saw mechanism.

  16. Shedding light on proteins, nucleic acids, cells, humans and fish

    NASA Technical Reports Server (NTRS)

    Setlow, Richard B.

    2002-01-01

    I was trained as a physicist in graduate school. Hence, when I decided to go into the field of biophysics, it was natural that I concentrated on the effects of light on relatively simple biological systems, such as proteins. The wavelengths absorbed by the amino acid subunits of proteins are in the ultraviolet (UV). The wavelengths that affect the biological activities, the action spectra, also are in the UV, but are not necessarily parallel to the absorption spectra. Understanding these differences led me to investigate the action spectra for affecting nucleic acids, and the effects of UV on viruses and cells. The latter studies led me to the discovery of the important molecular nature of the damages affecting DNA (cyclobutane pyrimidine dimers) and to the discovery of nucleotide excision repair. Individuals with the genetic disease xeroderma pigmentosum (XP) are extraordinarily sensitive to sunlight-induced skin cancer. The finding, by James Cleaver, that their skin cells were defective in DNA repair strongly suggested that DNA damage was a key step in carcinogenesis. Such information was important for estimating the wavelengths in sunlight responsible for human skin cancer and for predicting the effects of ozone depletion on the incidence of non-melanoma skin cancer. It took experiments with backcross hybrid fish to call attention to the probable role of the longer UV wavelengths not absorbed by DNA in the induction of melanoma. These reflections trace the biophysicist's path from molecules to melanoma.

  17. Shedding light on vampires: the phylogeny of vampyrellid amoebae revisited.

    PubMed

    Hess, Sebastian; Sausen, Nicole; Melkonian, Michael

    2012-01-01

    With the advent of molecular phylogenetic techniques the polyphyly of naked filose amoebae has been proven. They are interspersed in several supergroups of eukaryotes and most of them already found their place within the tree of life. Although the 'vampire amoebae' have attracted interest since the middle of the 19th century, the phylogenetic position and even the monophyly of this traditional group are still uncertain. In this study clonal co-cultures of eight algivorous vampyrellid amoebae and the respective food algae were established. Culture material was characterized morphologically and a molecular phylogeny was inferred using SSU rDNA sequence comparisons. We found that the limnetic, algivorous vampyrellid amoebae investigated in this study belong to a major clade within the Endomyxa Cavalier-Smith, 2002 (Cercozoa), grouping together with a few soil-dwelling taxa. They split into two robust clades, one containing species of the genus Vampyrella Cienkowski, 1865, the other containing the genus Leptophrys Hertwig & Lesser, 1874, together with terrestrial members. Supported by morphological data these clades are designated as the two families Vampyrellidae Zopf, 1885, and Leptophryidae fam. nov. Furthermore the order Vampyrellida West, 1901 was revised and now corresponds to the major vampyrellid clade within the Endomyxa, comprising the Vampyrellidae and Leptophryidae as well as several environmental sequences. In the light of the presented phylogenetic analyses morphological and ecological aspects, the feeding strategy and nutritional specialization within the vampyrellid amoebae are discussed. PMID:22355342

  18. Shedding Light on Vampires: The Phylogeny of Vampyrellid Amoebae Revisited

    PubMed Central

    Hess, Sebastian; Sausen, Nicole; Melkonian, Michael

    2012-01-01

    With the advent of molecular phylogenetic techniques the polyphyly of naked filose amoebae has been proven. They are interspersed in several supergroups of eukaryotes and most of them already found their place within the tree of life. Although the ‘vampire amoebae’ have attracted interest since the middle of the 19th century, the phylogenetic position and even the monophyly of this traditional group are still uncertain. In this study clonal co-cultures of eight algivorous vampyrellid amoebae and the respective food algae were established. Culture material was characterized morphologically and a molecular phylogeny was inferred using SSU rDNA sequence comparisons. We found that the limnetic, algivorous vampyrellid amoebae investigated in this study belong to a major clade within the Endomyxa Cavalier-Smith, 2002 (Cercozoa), grouping together with a few soil-dwelling taxa. They split into two robust clades, one containing species of the genus Vampyrella Cienkowski, 1865, the other containing the genus Leptophrys Hertwig & Lesser, 1874, together with terrestrial members. Supported by morphological data these clades are designated as the two families Vampyrellidae Zopf, 1885, and Leptophryidae fam. nov. Furthermore the order Vampyrellida West, 1901 was revised and now corresponds to the major vampyrellid clade within the Endomyxa, comprising the Vampyrellidae and Leptophryidae as well as several environmental sequences. In the light of the presented phylogenetic analyses morphological and ecological aspects, the feeding strategy and nutritional specialization within the vampyrellid amoebae are discussed. PMID:22355342

  19. Examining Booktalks to Shed Light on Authentic Classroom Discussion

    ERIC Educational Resources Information Center

    Hadjioannou, Xenia; Townsend, Jane S.

    2015-01-01

    In this qualitative case study, we examine the texture of talk in the booktalks of a fifth-grade classroom where authentic classroom discussions were common. The discourse analysis of classroom transcripts yielded 13 overlapping move categories describing the talk of the teacher, and nine the talk of the students. A comparison between authentic…

  20. Shedding Synchrotron Light on a Puzzle of Glasses

    ScienceCinema

    Chumakov, Aleksandr [European Synchrotron Radiation Facility, Grenoble, France

    2010-01-08

    Vibrational dynamics of glasses remains a point of controversial discussions. In particular, the density of vibrational states (DOS) reveals an excess of states above the Debye model called "boson peak." Despite the fact that this universal feature for all glasses has been known for more than 35 years, the nature of the boson peak is still not understood. The application of nuclear inelastic scattering via synchrotron radiation perhaps provides a clearer, more consistent picture of the subject. The distinguishing features of nuclear inelastic scattering relative to, e.g., neutron inelastic scattering, are ideal momentum integration and exact scaling of the DOS in absolute units. This allows for reliable comparison to data from other techniques such as Brillouin light scattering. Another strong point is ideal isotope selectivity: the DOS is measured for a single isotope with a specific low-energy nuclear transition. This allows for special "design" of an experiment to study, for instance, the dynamics of only center-of-mass motions. Recently, we have investigated the transformation of the DOS as a function of several key parameters such as temperature, cooling rate, and density. In all cases the transformation of the DOS is sufficiently well described by a transformation of the continuous medium, in particular, by changes of the macroscopic density and the sound velocity. These results suggest a collective sound-like nature of vibrational dynamics in glasses and cast doubts on microscopic models of glass dynamics. Further insight can be obtained in combined studies of glass with nuclear inelastic and inelastic neutron scattering. Applying two techniques, we have measured the energy dependence of the characteristic correlation length of atomic motions. The data do not reveal localization of atomic vibrations at the energy of the boson peak. Once again, the results suggest that special features of glass dynamics are related to extended motions and not to local models.

  1. Cosmological observations to shed light on possible variations

    NASA Astrophysics Data System (ADS)

    Wendt, M.; Reimers, D.; Molaro, P.

    2010-11-01

    Cosmology contributes a good deal to the investigation of variation of fundamental physical constants. High resolution data is available and allows for detailed analysis over cosmological distances and a multitude of methods were developed. The raised demand for precision requires a deep understanding of the limiting errors involved. The achievable accuracy is under debate and current observing proposals max out the capabilities of today's technology. The question for self-consistency in data analysis and effective techniques to handle unknown systematic errors is of increasing importance. This work is motivated by numerous findings of different groups that partially are in disagreement witch each other. A large part of these discrepancies reflects the different methods of handling systematic errors. Evidently systematics are not yet under control or fully understood. We try to emphasize the importance to take these errors, namely calibration issues, into account and put forward some measures adapted to the problem. Alternative approaches for some of the steps involved are introduced.

  2. Shedding light into the function of the earliest vertebrate skeleton

    NASA Astrophysics Data System (ADS)

    Martinez-Perez, Carlos; Purnell, Mark; Rayfield, Emily; Donoghue, Philip

    2016-04-01

    Conodonts are an extinct group of jawless vertebrates, the first in our evolutionary lineage to develop a biomineralized skeleton. As such, the conodont skeleton is of great significance because of the insights it provides concerning the biology and function of the primitive vertebrate skeleton. Conodont function has been debated for a century and a half on the basis of its paleocological importance in the Palaezoic ecosystems. However, due to the lack of extanct close representatives and the small size of the conodont element (under a milimiter in length) strongly limited their functional analysis, traditional restricted to analogy. More recently, qualitative approaches have been developed, facilitating tests of element function based on occlusal performance and analysis of microwear and microstructure. In this work we extend these approaches using novel quantitative experimental methods including Synchrotron Radiation X-ray Tomographic Microscopy or Finite Element Analysis to test hypotheses of conodont function. The development of high resolution virtual models of conodont elements, together with biomechanical approaches using Finite Element analysis, informed by occlusal and microwear analyses, provided conclusive support to test hypothesis of structural adaptation within the crown tissue microstructure, showing a close topological co-variation patterns of compressive and tensile stress distribution with different crystallite orientation. In addition, our computational analyses strongly support a tooth-like function for many conodont species. Above all, our study establishes a framework (experimental approach) in which the functional ecology of conodonts can be read from their rich taxonomy and phylogeny, representing an important attempt to understand the role of this abundant and diverse clade in the Phanerozoic marine ecosystems.

  3. The mummy returns… and sheds new light on old questions.

    PubMed

    Gilbert, M T P

    2011-10-01

    Whether as the ancient Egyptian crocodile-god Sobek, a terrifying predator of African waterways, or simply as a premium handbag leather, the Nile crocodile (Crocodylus niloticus) has long held the fascination of mankind. Despite 200 years of study, however, uncertainty remains as to its taxonomy. While resolving such issues are key to understanding the origins and biogeography of the so-called true crocodiles of genus Crocodylus, given widespread ongoing range contraction, such issues are paramount for design of future conservation strategies. In this issue of Molecular Ecology, Hekkala et al. (2011) apply analysis of modern, historic and ancient DNA (aDNA) to the questions, with far-reaching implications. First they demonstrate that, as currently described, the Nile crocodile is paraphyletic, with individuals from the east and western clades separated by a number of New World crocodile species. The consequences of this finding are as important for conservation efforts as for their impact on crocodile taxonomy. Furthermore, they strike at the heart of the long-standing debate over whether aDNA analysis of ancient Egyptian mummies is scientifically sound. PMID:24137623

  4. Shedding light on black boxes in protein identification.

    PubMed

    Vaudel, Marc; Venne, A Saskia; Berven, Frode S; Zahedi, René P; Martens, Lennart; Barsnes, Harald

    2014-05-01

    Performing a well thought-out proteomics data analysis can be a daunting task, especially for newcomers to the field. Even researchers experienced in the proteomics field can find it challenging to follow existing publication guidelines for MS-based protein identification and characterization in detail. One of the primary goals of bioinformatics is to enable any researcher to interpret the vast amounts of data generated in modern biology, by providing user-friendly and robust end-user applications, clear documentation, and corresponding teaching materials. In that spirit, we here present an extensive tutorial for peptide and protein identification, available at http://compomics.com/bioinformatics-for-proteomics. The material is completely based on freely available and open-source tools, and has already been used and refined at numerous international courses over the past 3 years. During this time, it has demonstrated its ability to allow even complete beginners to intuitively conduct advanced bioinformatics workflows, interpret the results, and understand their context. This tutorial is thus aimed at fully empowering users, by removing black boxes in the proteomics informatics pipeline. PMID:24678044

  5. Lagrangian analysis of vortex shedding behind a 2D airfoil

    NASA Astrophysics Data System (ADS)

    Cardwell, Blake; Mohseni, Kamran

    2007-11-01

    Identifying the coherent structures and their interactions in the mixing zone is a useful means in designing future flow control strategies. To this end, a Lagrangian analysis of two-dimensional vortex shedding over an Eppler 387 airfoil is presented. Stable and unstable material manifolds in the flow are identified. Unstable manifolds such a the shear layer characterize a barrier to fluid mixing and are easily visualized using dye injection in an experiment. On the other hand, stable manifolds are more difficult to visualize in an experiment. Reattachment lines are examples of such manifolds. As such the existence of these structures in the flow, is presented and how these structures are useful in understanding vortex shedding is explored. The manifold structure is also presented in a time averaged view, allowing a comparison with the traditional separation bubble. Furthermore, lobe dynamic calculation are performed and the fluid entrainment into shedded vortices are investigated. Finally, investigation of correlation between the behavior of the material manifolds and more traditional quantities such as skin friction, flow phase portrait, and pressure is presented.

  6. A previously undescribed organic residue sheds light on heat treatment in the Middle Stone Age.

    PubMed

    Schmidt, Patrick; Porraz, Guillaume; Bellot-Gurlet, Ludovic; February, Edmund; Ligouis, Bertrand; Paris, Céline; Texier, Pierre-Jean; Parkington, John E; Miller, Christopher E; Nickel, Klaus G; Conard, Nicholas J

    2015-08-01

    South Africa has in recent years gained increasing importance for our understanding of the evolution of 'modern human behaviour' during the Middle Stone Age (MSA). A key element in the suite of behaviours linked with modern humans is heat treatment of materials such as ochre for ritual purposes and stone prior to tool production. Until now, there has been no direct archaeological evidence for the exact procedure used in the heat treatment of silcrete. Through the analysis of heat-treated artefacts from the Howiesons Poort of Diepkloof Rock Shelter, we identified a hitherto unknown type of organic residue - a tempering-residue - that sheds light on the processes used for heat treatment in the MSA. This black film on the silcrete surface is an organic tar that contains microscopic fragments of charcoal and formed as a residue during the direct contact of the artefacts with hot embers of green wood. Our results suggest that heat treatment of silcrete was conducted directly using an open fire, similar to those likely used for cooking. These findings add to the discussion about the complexity of MSA behaviour and appear to contradict previous studies that had suggested that heat treatment of silcrete was a complex (i.e., requiring a large number of steps for its realization) and resource-consuming procedure. PMID:26073074

  7. Phylogeography sheds light on the central–marginal hypothesis in a Mediterranean narrow endemic plant

    PubMed Central

    Pouget, Marine; Youssef, Sami; Migliore, Jérémy; Juin, Marianick; Médail, Frédéric; Baumel, Alex

    2013-01-01

    ecological gradients. Conclusions This study highlights a case of strong population distinctiveness within a narrow range. Phylogeography sheds light on the historical role of the areas centrally situated in the distribution. The current range size and abundance patterns are not sufficient to predict the organization of genetic diversity. PMID:23962409

  8. Analysis and Prediction of Ice Shedding for a Full-Scale Heated Tail Rotor

    NASA Technical Reports Server (NTRS)

    Kreeger, Richard E.; Work, Andrew; Douglass, Rebekah; Gazella, Matthew; Koster, Zakery; Turk, Jodi

    2016-01-01

    When helicopters are to fly in icing conditions, it is necessary to consider the possibility of ice shed from the rotor blades. In 2013, a series of tests were conducted on a heated tail rotor at NASA Glenn's Icing Research Tunnel (IRT). The tests produced several shed events that were captured on camera. Three of these shed events were captured at a sufficiently high frame rate to obtain multiple images of the shed ice in flight that had a sufficiently long section of shed ice for analysis. Analysis of these shed events is presented and compared to an analytical Shedding Trajectory Model (STM). The STM is developed and assumes that the ice breaks off instantly as it reaches the end of the blade, while frictional and viscous forces are used as parameters to fit the STM. The trajectory of each shed is compared to that predicted by the STM, where the STM provides information of the shed group of ice as a whole. The limitations of the model's underlying assumptions are discussed in comparison to experimental shed events.

  9. The International Globe at Night Citizen-Science Campaign: Shedding Light on Light Pollution

    NASA Astrophysics Data System (ADS)

    Walker, C. E.; Pompea, S. M.

    2013-12-01

    For 8 years now, the Globe at Night campaign has invited citizen-scientists worldwide to measure and record the brightness of their night sky by hunting for the faintest stars in a particular constellation. Students for science projects and scientists for research use the data to monitor levels of brightness or 'light pollution' around the world. They also use the Globe at Night data to understand light pollution's effects on energy consumption, plants, wildlife and human health, as well as our ability to enjoy a starry night sky. The dates of the campaign for 2014 have been extended to every month during the year. Ten days each month (when the Moon is not up between 8pm and 10pm) are the recommended times to take measurements for the campaign. However, one can participate at other times and dates, as long as the Moon is not in the night sky and it is more than an hour after sunset or more than an hour before sunrise. New in 2014 will be an Android app that will allow you to input visual measurements anytime the Moon is not up. Also possibly included will be an iPhone app that will take sky brightness measurements. The campaign dates and the 5 easy steps to participating in the campaign are listed at www.globeatnight.org. You do not need to register. Once on the report page, you enter your location, date and time (automatic for a smart device). You find the constellation of the month in the night sky. (Help is on the website.) Then you choose which chart looks most like what you see toward the constellation. Choose the icon for how clear or cloudy it is and hit the submit button and you are done! The fifth step is returning later to the website to compare your observations on the world map to others from around the globe. Included on the Globe at Night website are many helpful resources and tools from finding the constellations used in the campaign, to understanding concepts like light pollution, to games that test your expertise in choosing 'limiting magnitudes

  10. Navigating the gender minefield: An IPV prevention campaign sheds light on the gender gap.

    PubMed

    Keller, Sarah N; Honea, Joy C

    2016-01-01

    This article examines how differences in male and female views about intimate partner violence (IPV) contributed to divergent responses to a prevention campaign conducted in the western USA. The study examines focus groups (n = 22) and in-depth interview data (n = 13) collected during campaign development to shed light on quantitative results indicating that women (but not men) increased their perceived severity of domestic violence and awareness of services from pre-test to post-test, while male attitudes moved in the opposite direction. Results of the qualitative study provide the basis for the authors' conclusions about why reactions differed: (1) men's unwillingness to view abuse within a gender context limits men's ability to accept the inequity in statistically demonstrated male and female roles as perpetrators and victims; (2) male resentment of existing gender stereotypes contributed to a rejection of campaign messages that utilised gender prevalence statistics to depict images showing men as perpetrators and women as victims; and (3) victim blaming attitudes contributed to resistance to empathy for victims depicted in the campaign. The authors offer suggestions for future campaigns that foster agency among both perpetrators and survivors while confronting the structural barriers to enacting change. PMID:25995024

  11. Integrative analyses shed new light on human ribosomal protein gene regulation.

    PubMed

    Li, Xin; Zheng, Yiyu; Hu, Haiyan; Li, Xiaoman

    2016-01-01

    Ribosomal protein genes (RPGs) are important house-keeping genes that are well-known for their coordinated expression. Previous studies on RPGs are largely limited to their promoter regions. Recent high-throughput studies provide an unprecedented opportunity to study how human RPGs are transcriptionally modulated and how such transcriptional regulation may contribute to the coordinate gene expression in various tissues and cell types. By analyzing the DNase I hypersensitive sites under 349 experimental conditions, we predicted 217 RPG regulatory regions in the human genome. More than 86.6% of these computationally predicted regulatory regions were partially corroborated by independent experimental measurements. Motif analyses on these predicted regulatory regions identified 31 DNA motifs, including 57.1% of experimentally validated motifs in literature that regulate RPGs. Interestingly, we observed that the majority of the predicted motifs were shared by the predicted distal and proximal regulatory regions of the same RPGs, a likely general mechanism for enhancer-promoter interactions. We also found that RPGs may be differently regulated in different cells, indicating that condition-specific RPG regulatory regions still need to be discovered and investigated. Our study advances the understanding of how RPGs are coordinately modulated, which sheds light to the general principles of gene transcriptional regulation in mammals. PMID:27346035

  12. Genetic and Epigenetic Diversities Shed Light on Domestication of Cultivated Ginseng (Panax ginseng).

    PubMed

    Li, Ming-Rui; Shi, Feng-Xue; Zhou, Yu-Xin; Li, Ya-Ling; Wang, Xin-Feng; Zhang, Cui; Wang, Xu-Tong; Liu, Bao; Xiao, Hong-Xing; Li, Lin-Feng

    2015-11-01

    Chinese ginseng (Panax ginseng) is a medically important herb within Panax and has crucial cultural values in East Asia. As the symbol of traditional Chinese medicine, Chinese ginseng has been used as a herbal remedy to restore stamina and capacity in East Asia for thousands of years. To address the evolutionary origin and domestication history of cultivated ginseng, we employed multiple molecular approaches to investigate the genetic structures of cultivated and wild ginseng across their distribution ranges in northeastern Asia. Phylogenetic and population genetic analyses revealed that the four cultivated ginseng landraces, COMMON, BIANTIAO, SHIZHU, and GAOLI (also known as Korean ginseng), were not domesticated independently and Fusong Town is likely one of the primary domestication centers. In addition, our results from population genetic and epigenetic analyses demonstrated that cultivated ginseng maintained high levels of genetic and epigenetic diversity, but showed distinct cytosine methylation patterns compared with wild ginseng. The patterns of genetic and epigenetic variation revealed by this study have shed light on the domestication history of cultivated ginseng, which may serve as a framework for future genetic improvements. PMID:26278367

  13. Integrative analyses shed new light on human ribosomal protein gene regulation

    PubMed Central

    Li, Xin; Zheng, Yiyu; Hu, Haiyan; Li, Xiaoman

    2016-01-01

    Ribosomal protein genes (RPGs) are important house-keeping genes that are well-known for their coordinated expression. Previous studies on RPGs are largely limited to their promoter regions. Recent high-throughput studies provide an unprecedented opportunity to study how human RPGs are transcriptionally modulated and how such transcriptional regulation may contribute to the coordinate gene expression in various tissues and cell types. By analyzing the DNase I hypersensitive sites under 349 experimental conditions, we predicted 217 RPG regulatory regions in the human genome. More than 86.6% of these computationally predicted regulatory regions were partially corroborated by independent experimental measurements. Motif analyses on these predicted regulatory regions identified 31 DNA motifs, including 57.1% of experimentally validated motifs in literature that regulate RPGs. Interestingly, we observed that the majority of the predicted motifs were shared by the predicted distal and proximal regulatory regions of the same RPGs, a likely general mechanism for enhancer-promoter interactions. We also found that RPGs may be differently regulated in different cells, indicating that condition-specific RPG regulatory regions still need to be discovered and investigated. Our study advances the understanding of how RPGs are coordinately modulated, which sheds light to the general principles of gene transcriptional regulation in mammals. PMID:27346035

  14. Molecular immunotherapy might shed a light on the treatment strategies for disc degeneration and herniation.

    PubMed

    Sun, Zhen; Liu, Zhi-Heng; Chen, Yu-fei; Zhang, Yong-zhao; Wan, Zhong-yuan; Zhang, Wei-lin; Che, Lu; Liu, Xu; Wang, Hai-Qiang; Luo, Zhuo-Jing

    2013-09-01

    Despite surgical discectomy is one of the most effective treatments for intervertebral disc degeneration and lumbar disc herniation, a number of patients still complain of reserved low back pain, sciatica and numbness post-operatively with decreased life quality. Sciatica in patients with disc herniation is not only due to mechanical compression from herniated nucleus pulposus, but chemical and immunity agents. The intervertebral disc is composed of annulus fibrosus in the wedge and gelatinous nucleus pulposus in the centre with cartilage endplate sandwiched. Similar to other immune privilege organs, human intervertebral disc is one of the biggest avascular structures with FasL expression. Moreover, FasL-Fas and TRAIL death pathways might play roles in the machinery of immune privilege of the disc. We found that down-regulated miR-155 promotes Fas-mediated apoptosis in disc degeneration. Furthermore, once exposed to human immune system, nucleus pulposus can activate multiple specific and non-specific immune responses with cellular and fluid immune cells and molecules involved. Taken together, we hypothesize that a combined molecular immunotherapy with local and systemic immunity regulators might shed a novel light on the treatment strategies for disc degeneration and herniation. PMID:23849654

  15. Hellbender Genome Sequences Shed Light on Genomic Expansion at the Base of Crown Salamanders

    PubMed Central

    Sun, Cheng; Mueller, Rachel Lockridge

    2014-01-01

    Among animals, genome sizes range from 20 Mb to 130 Gb, with 380-fold variation across vertebrates. Most of the largest vertebrate genomes are found in salamanders, an amphibian clade of 660 species. Thus, salamanders are an important system for studying causes and consequences of genomic gigantism. Previously, we showed that plethodontid salamander genomes accumulate higher levels of long terminal repeat (LTR) retrotransposons than do other vertebrates, although the evolutionary origins of such sequences remained unexplored. We also showed that some salamanders in the family Plethodontidae have relatively slow rates of DNA loss through small insertions and deletions. Here, we present new data from Cryptobranchus alleganiensis, the hellbender. Cryptobranchus and Plethodontidae span the basal phylogenetic split within salamanders; thus, analyses incorporating these taxa can shed light on the genome of the ancestral crown salamander lineage, which underwent expansion. We show that high levels of LTR retrotransposons likely characterize all crown salamanders, suggesting that disproportionate expansion of this transposable element (TE) class contributed to genomic expansion. Phylogenetic and age distribution analyses of salamander LTR retrotransposons indicate that salamanders’ high TE levels reflect persistence and diversification of ancestral TEs rather than horizontal transfer events. Finally, we show that relatively slow DNA loss rates through small indels likely characterize all crown salamanders, suggesting that a decreased DNA loss rate contributed to genomic expansion at the clade’s base. Our identification of shared genomic features across phylogenetically distant salamanders is a first step toward identifying the evolutionary processes underlying accumulation and persistence of high levels of repetitive sequence in salamander genomes. PMID:25115007

  16. Conservation of fruit dehiscence pathways between Lepidium campestre and Arabidopsis thaliana sheds light on the regulation of INDEHISCENT.

    PubMed

    Lenser, Teresa; Theißen, Günter

    2013-11-01

    The mode of fruit opening is an important agronomic and evolutionary trait that has been studied intensively in the major plant model system Arabidopsis thaliana. Because fruit morphology is highly variable between species, and is also often the target of artificial selection during breeding, it is interesting to investigate whether a change in fruit morphology may alter the developmental pathway leading to fruit opening. Here we have studied fruit development in Lepidium campestre, a Brassicaceae species that forms silicles instead of siliques. Transgenic L. campestre plants with altered expression levels of orthologs of A. thaliana fruit developmental genes (ALCATRAZ, FRUITFULL, INDEHISCENT and SHATTERPROOF1,2) were found to be defective in fruit dehiscence, and anatomical sections revealed similar changes in tissue patterning as found in respective A. thaliana mutants. Gene expression analyses demonstrated a high degree of conservation in gene regulatory circuits, indicating that, despite great differences in fruit morphology, the process of fruit opening remains basically unchanged between species. Interestingly, our data identify ALCATRAZ as a negative regulator of INDEHISCENT in L. campestre. By mutant analysis, we found the same regulatory relationship in A. thaliana also, thereby shedding new light on how ALCATRAZ drives separation layer formation. PMID:24004048

  17. ARTIFICIAL LIGHTING EXTENDS THE DURATION OF FECAL SHEDDING OF E. COLI O157 IN FEEDLOT CATTLE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seasonal shedding of E. coli O157 in cattle in the United States is well documented however reasons for this phenomenon are unknown. Fecal prevalence is typically highest in the summer and early fall, decreasing to low or undetectable levels in the winter months. Ambient temperature has been sugge...

  18. ITS Polymorphisms Shed Light on Hybrid Evolution in Apomictic Plants: A Case Study on the Ranunculus auricomus Complex

    PubMed Central

    Hodač, Ladislav; Scheben, Armin Patrick; Hojsgaard, Diego; Paun, Ovidiu; Hörandl, Elvira

    2014-01-01

    The reconstruction of reticulate evolutionary histories in plants is still a major methodological challenge. Sequences of the ITS nrDNA are a popular marker to analyze hybrid relationships, but variation of this multicopy spacer region is affected by concerted evolution, high intraindividual polymorphism, and shifts in mode of reproduction. The relevance of changes in secondary structure is still under dispute. We aim to shed light on the extent of polymorphism within and between sexual species and their putative natural as well as synthetic hybrid derivatives in the Ranunculus auricomus complex to test morphology-based hypotheses of hybrid origin and parentage of taxa. We employed direct sequencing of ITS nrDNA from 68 individuals representing three sexuals, their synthetic hybrids and one sympatric natural apomict, as well as cloning of ITS copies in four representative individuals, RNA secondary structure analysis, and landmark geometric morphometric analysis on leaves. Phylogenetic network analyses indicate additivity of parental ITS variants in both synthetic and natural hybrids. The triploid synthetic hybrids are genetically much closer to their maternal progenitors, probably due to ploidy dosage effects, although exhibiting a paternal-like leaf morphology. The natural hybrids are genetically and morphologically closer to the putative paternal progenitor species. Secondary structures of ITS1-5.8S-ITS2 were rather conserved in all taxa. The observed similarities in ITS polymorphisms suggest that the natural apomict R. variabilis is an ancient hybrid of the diploid sexual species R. notabilis and the sexual species R. cassubicifolius. The additivity pattern shared by R. variabilis and the synthetic hybrids supports an evolutionary and biogeographical scenario that R. variabilis originated from ancient hybridization. Concerted evolution of ITS copies in R. variabilis is incomplete, probably due to a shift to asexual reproduction. Under the condition of

  19. Shedding light on moths: shorter wavelengths attract noctuids more than geometrids

    PubMed Central

    Somers-Yeates, Robin; Hodgson, David; McGregor, Peter K.; Spalding, Adrian; ffrench-Constant, Richard H.

    2013-01-01

    With moth declines reported across Europe, and parallel changes in the amount and spectra of street lighting, it is important to understand exactly how artificial lights affect moth populations. We therefore compared the relative attractiveness of shorter wavelength (SW) and longer wavelength (LW) lighting to macromoths. SW light attracted significantly more individuals and species of moth, either when used alone or in competition with LW lighting. We also found striking differences in the relative attractiveness of different wavelengths to different moth groups. SW lighting attracted significantly more Noctuidae than LW, whereas both wavelengths were equally attractive to Geometridae. Understanding the extent to which different groups of moth are attracted to different wavelengths of light will be useful in determining the impact of artificial light on moth populations. PMID:23720524

  20. Forests and floods: A new paradigm sheds light on age-old controversies

    NASA Astrophysics Data System (ADS)

    Alila, Younes; Kuraś, Piotr K.; Schnorbus, Markus; Hudson, Robert

    2009-08-01

    The science of forests and floods is embroiled in conflict and is in urgent need of reevaluation in light of changing climates, insect epidemics, logging, and deforestation worldwide. Here we show how an inappropriate pairing of floods by meteorological input in analysis of covariance (ANCOVA) and analysis of variance (ANOVA), statistical tests used extensively for evaluating the effects of forest harvesting on floods smaller and larger than an average event, leads to incorrect estimates of changes in flood magnitude because neither the tests nor the pairing account for changes in flood frequency. We also illustrate how ANCOVA and ANOVA, originally designed for detecting changes in means, do not account for any forest harvesting induced change in variance and its critical effects on the frequency and magnitude of larger floods. The outcomes of numerous studies, which applied ANCOVA and ANOVA inappropriately, are based on logical fallacies and have contributed to an ever widening disparity between science, public perception, and often land-management policies for decades. We demonstrate how only an approach that pairs floods by similar frequency, well established in other disciplines, can evaluate the effects of forest harvesting on the inextricably linked magnitude and frequency of floods. We call for a reevaluation of past studies and the century-old, preconceived, and indefensible paradigm that shaped our scientific perception of the relation between forests, floods, and the biophysical environment.

  1. Stable transgenesis in the marine annelid Platynereis dumerilii sheds new light on photoreceptor evolution

    PubMed Central

    Backfisch, Benjamin; Veedin Rajan, Vinoth Babu; Fischer, Ruth M.; Lohs, Claudia; Arboleda, Enrique; Tessmar-Raible, Kristin; Raible, Florian

    2013-01-01

    Research in eye evolution has mostly focused on eyes residing in the head. In contrast, noncephalic light sensors are far less understood and rather regarded as evolutionary innovations. We established stable transgenesis in the annelid Platynereis, a reference species for evolutionary and developmental comparisons. EGFP controlled by cis-regulatory elements of r-opsin, a characteristic marker for rhabdomeric photoreceptors, faithfully recapitulates known r-opsin expression in the adult eyes, and marks a pair of pigment-associated frontolateral eyelets in the brain. Unexpectedly, transgenic animals revealed an additional series of photoreceptors in the ventral nerve cord as well as photoreceptors that are located in each pair of the segmental dorsal appendages (notopodia) and project into the ventral nerve cord. Consistent with a photosensory function of these noncephalic cells, decapitated animals display a clear photoavoidance response. Molecular analysis of the receptors suggests that they differentiate independent of pax6, a gene involved in early eye development of many metazoans, and that the ventral cells may share origins with the Hesse organs in the amphioxus neural tube. Finally, expression analysis of opn4×-2 and opn4m-2, two zebrafish orthologs of Platynereis r-opsin, reveals that these genes share expression in the neuromasts, known mechanoreceptors of the lateral line peripheral nervous system. Together, this establishes that noncephalic photoreceptors are more widespread than assumed, and may even reflect more ancient aspects of sensory systems. Our study marks significant advance for the understanding of photoreceptor cell (PRC) evolution and development and for Platynereis as a functional lophotrochozoan model system. PMID:23284166

  2. SHEDDING LIGHT ON CORALS HEALTH: INTERACTIONS OF CLIMATE CHANGE AND SOLAR RADIATION WITH BLEACHING

    EPA Science Inventory

    Coral bleaching and declines in coral reef health in recent years have been attributed in part to processes driven by UV and/or visible light. For coral assemblages, exposure to UV light is often an unavoidable consequence of having access to visible (photosynthetically active) ...

  3. Shedding Light on Bird Egg Color: Pigment as Parasol and the Dark Car Effect.

    PubMed

    Lahti, David C; Ardia, Daniel R

    2016-05-01

    The vibrant colors of many birds' eggs, particularly those that are blue to blue-green, are extraordinary in that they are striking traits present in hundreds of species that have nevertheless eluded evolutionary functional explanation. We propose that egg pigmentation mediates a trade-off between two routes by which solar radiation can harm bird embryos: transmittance through the eggshell and overheating through absorbance. We quantitatively test four components of this hypothesis on variably colored eggs of the village weaverbird (Ploceus cucullatus) in a controlled light environment: (1) damaging ultraviolet radiation can transmit through bird eggshells, (2) infrared radiation at natural intensities can heat the interior of eggs, (3) more intense egg coloration decreases light transmittance ("pigment as parasol"), and (4) more intense egg coloration increases absorbance of light by the eggshell and heats the egg interior ("dark car effect"). Results support all of these predictions. Thus, in sunlit nesting environments, less pigmentation will increase the detrimental effect of transmittance, but more pigmentation will increase the detrimental effect of absorbance. The optimal pigmentation level for a bird egg in a given light environment, all other things being equal, will depend on the balance between light transmittance and absorbance in relation to embryo fitness. PMID:27104989

  4. Shedding New Light on an Old Problem: The Estimation of Shadow Sizes in Children and Adults

    ERIC Educational Resources Information Center

    Ebersbach, Mirjam; Resing, Wilma C. M.

    2007-01-01

    Two experiments using the "projection of shadows" paradigm investigated multidimensional reasoning, implicit and explicit knowledge, and the nonlinearity concept in 5-, 9-, and 13-year-olds and adults. Participants estimated the resulting shadow lengths of differently sized objects, placed at varying distances from a light source. Experiment 1…

  5. Hands-On Whole Science. Shining Science: Shed Some Light on the Science of Summer.

    ERIC Educational Resources Information Center

    Kepler, Lynne

    1992-01-01

    Presents summer science activities for elementary students which focus on sunlight and other natural and artificial light sources (e.g., fire, flashlights, and fireflies). Related activities which involve language arts, art, and math are included. A reproducible page teaches children Morse Code using a flashlight. (SM)

  6. A Lagrangian analysis of a two-dimensional airfoil with vortex shedding

    NASA Astrophysics Data System (ADS)

    Lipinski, Doug; Cardwell, Blake; Mohseni, Kamran

    2008-08-01

    Using invariant material manifolds and flow topology, the flow behavior and structure of flow around a two-dimensional Eppler 387 airfoil is examined with an emphasis on vortex shedding and the time-dependent reattachment profile. The examination focuses on low Reynolds number (Re = 60 000) flow at several angles of attack. Using specialized software, we identify invariant manifolds in the flow and use these structures to illuminate the process of vortex formation and the periodic behavior of the reattachment profile. Our analysis concludes with a topological view of the flow, including fixed points and a discussion of phase plots and the frequency spectrum of several key points in the flow. The behavior of invariant manifolds directly relates to the flow topology and illuminates some aspects seen in phase space during vortex shedding. Furthermore, it highlights the reattachment behavior in ways not seen before.

  7. Individual Subject Meta-Analysis of Parameters for Giardia duodenalis Shedding in Animal Experimental Models

    PubMed Central

    Adell, A. D.; Miller, W. A.; Harvey, D. J.; Van Wormer, E.; Wuertz, S.; Conrad, P. A.

    2014-01-01

    Giardia duodenalis is a zoonotic protozoan parasite with public health importance worldwide. While articles about animal model infectivity have been published for G. duodenalis, the studies have used diverse protocols and parameters to evaluate the infectivity of this protozoan parasite. Hence, the objectives of this study were to (1) conduct a meta-analysis of published literature for cyst shedding and diarrhea outcomes in animal models and (2) develop recommendations to help standardize experimental dose response studies. Results showed that, for the outcome of cyst shedding in faeces, the covariates of infective stage (cyst versus trophozoite), Giardia dose, and the interactions between doses and infective stage, as well as dose and species of experimental host, were all significant (P value ≤ 0.05). This study suggests inoculation of the experimental host with cysts rather than trophozoites and administration of higher doses of Giardia will most likely result in cyst shedding. Based on the results of this meta-analysis, the infective stage (cyst versus trophozoite), parasite dose, and the interactions between dose and infective stage, as well as dose and species of experimental host, should be considered when designing experimental dose response studies that will assist in the study of zoonotic neglected tropical diseases globally. PMID:24800229

  8. Land-based lidar mapping: a new surveying technique to shed light on rapid topographic change

    USGS Publications Warehouse

    Collins, Brian D.; Kayen, Robert

    2006-01-01

    The rate of natural change in such dynamic environments as rivers and coastlines can sometimes overwhelm the monitoring capacity of conventional surveying methods. In response to this limitation, U.S. Geological Survey (USGS) scientists are pioneering new applications of light detection and ranging (lidar), a laser-based scanning technology that promises to greatly increase our ability to track rapid topographic changes and manage their impact on affected communities.

  9. Afterglow Observations Shed New Light on the Nature of X-ray Flashes

    SciTech Connect

    Granot, J

    2005-02-17

    X-ray flashes (XRFs) and X-ray rich gamma-ray bursts (XRGRBs) share many observational characteristics with long duration ({approx}> 2 s) GRBs, but the reason for which the spectral energy distribution of their prompt emission peaks at lower photon energies, E{sub p}, is still a subject of debate. Although many different models have been invoked in order to explain the lower values of E{sub p}, their implications for the afterglow emission were not considered in most cases, mainly because observations of XRF afterglows have become available only recently. Here we examine the predictions of the various XRF models for the afterglow emission, and test them against the observations of XRF 030723 and XRGRB 041006, the events with the best monitored afterglow light curves in their respective class. We show that most existing XRF models are hard to reconcile with the observed afterglow light curves, which are very flat at early times. Such light curves are, however, naturally produced by a roughly uniform jet with relatively sharp edges that is viewed off-axis (i.e. from outside of the jet aperture). This type of model self consistently accommodates both the observed prompt emission and the afterglow light curves of XRGRB 041006 and XRF 030723, implying viewing angles {theta}{sub obs} from the jet axis of ({theta}{sub obs}-{theta}{sub 0}) {approx} 0.15 {theta}{sub 0} and ({theta}{sub obs}-{theta}{sub 0}) {approx} {theta}{sub 0}, respectively, where {theta}{sub 0} {approx} 3{sup o} is the half-opening angle of the jet. This suggests that GRBs, XRGRBs and XRFs are intrinsically similar relativistic jets viewed from different angles. It is then natural to identify GRBs with {gamma}({theta}{sub obs} - {theta}{sub 0}) {approx}< 1, XRGRBs with 1 {approx}< ({theta}{sub obs} - {theta}{sub 0}) {approx}< a few, and XRFs with {gamma}({theta}{sub obs} - {theta}{sub 0}) {approx}> a few, where {gamma} is the Lorentz factor of the outflow near the edge of the jet from which most of the

  10. Shedding Light on a New Treatment for Diabetic Wound Healing: A Review on Phototherapy

    PubMed Central

    Houreld, Nicolette N.

    2014-01-01

    Impaired wound healing is a common complication associated with diabetes with complex pathophysiological underlying mechanisms and often necessitates amputation. With the advancement in laser technology, irradiation of these wounds with low-intensity laser irradiation (LILI) or phototherapy, has shown a vast improvement in wound healing. At the correct laser parameters, LILI has shown to increase migration, viability, and proliferation of diabetic cells in vitro; there is a stimulatory effect on the mitochondria with a resulting increase in adenosine triphosphate (ATP). In addition, LILI also has an anti-inflammatory and protective effect on these cells. In light of the ever present threat of diabetic foot ulcers, infection, and amputation, new improved therapies and the fortification of wound healing research deserves better prioritization. In this review we look at the complications associated with diabetic wound healing and the effect of laser irradiation both in vitro and in vivo in diabetic wound healing. PMID:24511283

  11. SHEDDING NEW LIGHT ON NEURODEGENERATIVE DISEASES THROUGH THE MAMMALIAN TARGET OF RAPAMYCIN

    PubMed Central

    Chong, Zhao Zhong; Shang, Yan Chen; Wang, Shaohui; Maiese, Kenneth

    2012-01-01

    Neurodegenerative disorders affect a significant portion of the world's population leading to either disability or death for almost 30 million individuals worldwide. One novel therapeutic target that may offer promise for multiple disease entities that involve Alzheimer's disease, Parkinson's disease, epilepsy, trauma, stroke, and tumors of the nervous system is the mammalian target of rapamycin (mTOR). mTOR signaling is dependent upon the mTORC1 and mTORC2 complexes that are composed of mTOR and several regulatory proteins including the tuberous sclerosis complex (TSC1, hamartin/ TSC2, tuberin). Through a number of integrated cell signaling pathways that involve those of mTORC1 and mTORC2 as well as more novel signaling tied to cytokines, Wnt, and forkhead, mTOR can foster stem cellular proliferation, tissue repair and longevity, and synaptic growth by modulating mechanisms that foster both apoptosis and autophagy. Yet, mTOR through its proliferative capacity may sometimes be detrimental to central nervous system recovery and even promote tumorigenesis. Further knowledge of mTOR and the critical pathways governed by this serine/threonine protein kinase can bring new light for neurodegeneration and other related diseases that currently require new and robust treatments. PMID:22980037

  12. Evidence of Coat Color Variation Sheds New Light on Ancient Canids

    PubMed Central

    Ollivier, Morgane; Tresset, Anne; Hitte, Christophe; Petit, Coraline; Hughes, Sandrine; Gillet, Benjamin; Duffraisse, Marilyne; Pionnier-Capitan, Maud; Lagoutte, Laetitia; Arbogast, Rose-Marie; Balasescu, Adrian; Boroneant, Adina; Mashkour, Marjan; Vigne, Jean-Denis; Hänni, Catherine

    2013-01-01

    We have used a paleogenetics approach to investigate the genetic landscape of coat color variation in ancient Eurasian dog and wolf populations. We amplified DNA fragments of two genes controlling coat color, Mc1r (Melanocortin 1 Receptor) and CBD103 (canine-β-defensin), in respectively 15 and 19 ancient canids (dogs and wolf morphotypes) from 14 different archeological sites, throughout Asia and Europe spanning from ca. 12 000 B.P. (end of Upper Palaeolithic) to ca. 4000 B.P. (Bronze Age). We provide evidence of a new variant (R301C) of the Melanocortin 1 receptor (Mc1r) and highlight the presence of the beta-defensin melanistic mutation (CDB103-K locus) on ancient DNA from dog-and wolf-morphotype specimens. We show that the dominant KB allele (CBD103), which causes melanism, and R301C (Mc1r), the variant that may cause light hair color, are present as early as the beginning of the Holocene, over 10 000 years ago. These results underline the genetic diversity of prehistoric dogs. This diversity may have partly stemmed not only from the wolf gene pool captured by domestication but also from mutations very likely linked to the relaxation of natural selection pressure occurring in-line with this process. PMID:24098367

  13. Hippocampal formation: shedding light on the influence of sex and stress on the brain

    PubMed Central

    McEwen, Bruce S.; Milner, Teresa A.

    2007-01-01

    The hippocampus is a malleable brain region that responds to external agents such as hormones and stressors. Investigations that began in our laboratories with the Golgi technique and an appreciation of hippocampal neuroanatomy at the light and electron microscopic levels have led us down a path that has uncovered unexpected structural plasticity in the adult brain along with unanticipated cellular and molecular mechanisms of this plasticity and of hormone mediation of these effects. This chapter reviews the history of discoveries in our two laboratories involving the actions of estradiol and stress hormones on neuronal structure and function and then discusses the insight to hormone-brain interactions that this has engendered. These discoveries have led us to a new view of brain structural plasticity and the role and mechanism of steroid hormone action involving both genomic and non-genomic pathways. This new view is consistent with the predictions of Cajal in his book “The Structure of Ammon’s horn”, 1892. PMID:17395265

  14. Shedding More Light and Less Heat on the Results of School Integration. The Georgia Experience.

    ERIC Educational Resources Information Center

    Christison, Milton; Sida, Donald

    One hundred and eighty-eight Georgia school system superintendents were polled in the Spring of 1976 as to their perceptions and experiences concerning the effects of school integration. This paper presents the results of this investigation. Three broad areas were selected for analysis: (1) integration outcomes affecting the public schools, (2)…

  15. Discovery of Giant X-Ray Disk Sheds Light on Elliptical Galaxies

    NASA Astrophysics Data System (ADS)

    2002-12-01

    Ohio University astronomers have discovered the largest disk of hot, X-ray emitting gas ever observed in the universe: At 90,000 light years in diameter, it's about 100,000 times the size of any comparable object. The disk, spinning through a distant galaxy, is more than just an interstellar oddity, the researchers say. The object could offer new information about the way certain galaxies form and evolve. About 20 percent of all galaxies are elliptical, the largest of the three types of galaxies in the universe. They differ from spiral galaxies like the Milky Way, as they lack new stars and spiral "arms." Scientists once believed that elliptical galaxies were ancient, simple systems that contained only old stars and formed in the early days of the universe. But new research suggests elliptical galaxies are more complex and dynamic. "It used to be thought that galaxies form and then sit there and age quietly over time. But now we understand that galaxies live, in the sense that there's an interplay of gas and stars," said Thomas Statler, an associate professor of physics and astronomy and lead author of the study, published in the Dec. 20 issue of the Astrophysical Journal. The newly discovered X-ray disk offers more evidence for that argument. Using NASA's Chandra X-ray Observatory, an orbiting spacecraft that houses the most powerful X-ray telescope in existence, the astronomers discovered the disk while analyzing data collected from NGC 1700, a young elliptical galaxy about 160 million light years from Earth. Giant in size and about 8 million degrees in temperature, the disk was an unexpected find for Statler and colleague Brian McNamara. But while its gargantuan scale is striking, the disk also yielded another surprise: The hot gas is not in calm balance with the gravitational forces as expected, but spinning through the galaxy. In fact, the giant, rotating X-ray disk suggests that this elliptical galaxy and perhaps others like it wasn't created by the merger of

  16. Shedding light on emotional perception: Interaction of brightness and semantic content in extrastriate visual cortex.

    PubMed

    Schettino, Antonio; Keil, Andreas; Porcu, Emanuele; Müller, Matthias M

    2016-06-01

    The rapid extraction of affective cues from the visual environment is crucial for flexible behavior. Previous studies have reported emotion-dependent amplitude modulations of two event-related potential (ERP) components - the N1 and EPN - reflecting sensory gain control mechanisms in extrastriate visual areas. However, it is unclear whether both components are selective electrophysiological markers of attentional orienting toward emotional material or are also influenced by physical features of the visual stimuli. To address this question, electrical brain activity was recorded from seventeen male participants while viewing original and bright versions of neutral and erotic pictures. Bright neutral scenes were rated as more pleasant compared to their original counterpart, whereas erotic scenes were judged more positively when presented in their original version. Classical and mass univariate ERP analysis showed larger N1 amplitude for original relative to bright erotic pictures, with no differences for original and bright neutral scenes. Conversely, the EPN was only modulated by picture content and not by brightness, substantiating the idea that this component is a unique electrophysiological marker of attention allocation toward emotional material. Complementary topographic analysis revealed the early selective expression of a centro-parietal positivity following the presentation of original erotic scenes only, reflecting the recruitment of neural networks associated with sustained attention and facilitated memory encoding for motivationally relevant material. Overall, these results indicate that neural networks subtending the extraction of emotional information are differentially recruited depending on low-level perceptual features, which ultimately influence affective evaluations. PMID:26994832

  17. Resolving phenylalanine metabolism sheds light on natural synthesis of penicillin G in Penicillium chrysogenum.

    PubMed

    Veiga, Tânia; Solis-Escalante, Daniel; Romagnoli, Gabriele; ten Pierick, Angela; Hanemaaijer, Mark; Deshmukh, Amit T; Deshmuhk, Amit; Wahl, Aljoscha; Pronk, Jack T; Daran, Jean-Marc

    2012-02-01

    The industrial production of penicillin G by Penicillium chrysogenum requires the supplementation of the growth medium with the side chain precursor phenylacetate. The growth of P. chrysogenum with phenylalanine as the sole nitrogen source resulted in the extracellular production of phenylacetate and penicillin G. To analyze this natural pathway for penicillin G production, chemostat cultures were switched to [U-(13)C]phenylalanine as the nitrogen source. The quantification and modeling of the dynamics of labeled metabolites indicated that phenylalanine was (i) incorporated in nascent protein, (ii) transaminated to phenylpyruvate and further converted by oxidation or by decarboxylation, and (iii) hydroxylated to tyrosine and subsequently metabolized via the homogentisate pathway. The involvement of the homogentisate pathway was supported by the comparative transcriptome analysis of P. chrysogenum cultures grown with phenylalanine and with (NH(4))(2)SO(4) as the nitrogen source. This transcriptome analysis also enabled the identification of two putative 2-oxo acid decarboxylase genes (Pc13g9300 and Pc18g01490). cDNAs of both genes were cloned and expressed in the 2-oxo-acid-decarboxylase-free Saccharomyces cerevisiae strain CEN.PK711-7C (pdc1 pdc5 pdc6Δ aro10Δ thi3Δ). The introduction of Pc13g09300 restored the growth of this S. cerevisiae mutant on glucose and phenylalanine, thereby demonstrating that Pc13g09300 encodes a dual-substrate pyruvate and phenylpyruvate decarboxylase, which plays a key role in an Ehrlich-type pathway for the production of phenylacetate in P. chrysogenum. These results provide a basis for the metabolic engineering of P. chrysogenum for the production of the penicillin G side chain precursor phenylacetate. PMID:22158714

  18. Resolving Phenylalanine Metabolism Sheds Light on Natural Synthesis of Penicillin G in Penicillium chrysogenum

    PubMed Central

    Veiga, Tânia; Solis-Escalante, Daniel; Romagnoli, Gabriele; ten Pierick, Angela; Hanemaaijer, Mark; Deshmuhk, Amit; Wahl, Aljoscha; Pronk, Jack T.

    2012-01-01

    The industrial production of penicillin G by Penicillium chrysogenum requires the supplementation of the growth medium with the side chain precursor phenylacetate. The growth of P. chrysogenum with phenylalanine as the sole nitrogen source resulted in the extracellular production of phenylacetate and penicillin G. To analyze this natural pathway for penicillin G production, chemostat cultures were switched to [U-13C]phenylalanine as the nitrogen source. The quantification and modeling of the dynamics of labeled metabolites indicated that phenylalanine was (i) incorporated in nascent protein, (ii) transaminated to phenylpyruvate and further converted by oxidation or by decarboxylation, and (iii) hydroxylated to tyrosine and subsequently metabolized via the homogentisate pathway. The involvement of the homogentisate pathway was supported by the comparative transcriptome analysis of P. chrysogenum cultures grown with phenylalanine and with (NH4)2SO4 as the nitrogen source. This transcriptome analysis also enabled the identification of two putative 2-oxo acid decarboxylase genes (Pc13g9300 and Pc18g01490). cDNAs of both genes were cloned and expressed in the 2-oxo-acid-decarboxylase-free Saccharomyces cerevisiae strain CEN.PK711-7C (pdc1 pdc5 pdc6Δ aro10Δ thi3Δ). The introduction of Pc13g09300 restored the growth of this S. cerevisiae mutant on glucose and phenylalanine, thereby demonstrating that Pc13g09300 encodes a dual-substrate pyruvate and phenylpyruvate decarboxylase, which plays a key role in an Ehrlich-type pathway for the production of phenylacetate in P. chrysogenum. These results provide a basis for the metabolic engineering of P. chrysogenum for the production of the penicillin G side chain precursor phenylacetate. PMID:22158714

  19. A new snake skull from the Paleocene of Bolivia sheds light on the evolution of macrostomatans.

    PubMed

    Scanferla, Agustín; Zaher, Hussam; Novas, Fernando E; de Muizon, Christian; Céspedes, Ricardo

    2013-01-01

    Macrostomatan snakes, one of the most diverse extant clades of squamates, display an impressive arsenal of cranial features to consume a vast array of preys. In the absence of indisputable fossil representatives of this clade with well-preserved skulls, the mode and timing of these extraordinary morphological novelties remain obscure. Here, we report the discovery of Kataria anisodonta n. gen. n. sp., a macrostomatan snake recovered in the Early Palaeocene locality of Tiupampa, Bolivia. The holotype consists of a partial, minute skull that exhibits a combination of booid and caenophidian characters, being the presence of an anisodont dentition and diastema in the maxilla the most distinctive trait. Phylogenetic analysis places Kataria basal to the Caenophidia+Tropidophiidae, and represents along with bolyeriids a distinctive clade of derived macrostomatans. The discovery of Kataria highlights the morphological diversity in the maxilla among derived macrostomatans, demonstrating the relevance of maxillary transformations in the evolution of this clade. Kataria represents the oldest macrostomatan skull recovered, revealing that the diversification of macrostomatans was well under way in early Tertiary times. This record also reinforces the importance of Gondwanan territories in the history of snakes, not only in the origin of the entire group but also in the evolution of ingroup clades. PMID:23469206

  20. Shed a light in fatigue detection with near-infrared spectroscopy during long-lasting driving

    NASA Astrophysics Data System (ADS)

    Gao, Yuan; Pan, Boan; Li, Kai; Li, Ting

    2016-03-01

    Fatigue driving is one of the leading roles to induce traffic accident and injury, which urgently desires a novel technique to monitor the fatigue level at driving. Functional near infrared spectroscopy (fNIRS) is capable of noninvasive monitoring brain-activities-related hemodynamic responses. Here, we developed a fINRS imager and setup a classic psychological experiment to trigger visual divided attention which varied responding to driving fatigue, and attempted to record the drive-fatigue-level correlated hemodynamic response in the prefrontal cortex. 7 volunteers were recruited to take 7 hours driving and the experimental test was repeated every 1 hour and 8 times in total. The hemodynamic response were extracted and graphed with pseudo image. The analysis on the relationship between the fNIRS-measured hemodynamic response and fatigue level finally displayed that the oxyhemoglobin concentration in one channel of left prefrontal lobe increased with driving duration in significant correlation. And the spatial pattern of hemodynamic response in the prefrontal lobe varied with driving duration as well. The findings indicated the potential of fNIRSmeasured hemodynamic index in some sensitive spot of prefrontal lobe as a driving fatigue indicator and the promising use of fNIRS in traffic safety field.

  1. A New Snake Skull from the Paleocene of Bolivia Sheds Light on the Evolution of Macrostomatans

    PubMed Central

    Scanferla, Agustín; Zaher, Hussam; Novas, Fernando E.; de Muizon, Christian; Céspedes, Ricardo

    2013-01-01

    Macrostomatan snakes, one of the most diverse extant clades of squamates, display an impressive arsenal of cranial features to consume a vast array of preys. In the absence of indisputable fossil representatives of this clade with well-preserved skulls, the mode and timing of these extraordinary morphological novelties remain obscure. Here, we report the discovery of Kataria anisodonta n. gen. n. sp., a macrostomatan snake recovered in the Early Palaeocene locality of Tiupampa, Bolivia. The holotype consists of a partial, minute skull that exhibits a combination of booid and caenophidian characters, being the presence of an anisodont dentition and diastema in the maxilla the most distinctive trait. Phylogenetic analysis places Kataria basal to the Caenophidia+Tropidophiidae, and represents along with bolyeriids a distinctive clade of derived macrostomatans. The discovery of Kataria highlights the morphological diversity in the maxilla among derived macrostomatans, demonstrating the relevance of maxillary transformations in the evolution of this clade. Kataria represents the oldest macrostomatan skull recovered, revealing that the diversification of macrostomatans was well under way in early Tertiary times. This record also reinforces the importance of Gondwanan territories in the history of snakes, not only in the origin of the entire group but also in the evolution of ingroup clades. PMID:23469206

  2. Familial Hemophagocytic Lymphohistiocytosis: When Rare Diseases Shed Light on Immune System Functioning

    PubMed Central

    Sieni, Elena; Cetica, Valentina; Hackmann, Yvonne; Coniglio, Maria Luisa; Da Ros, Martina; Ciambotti, Benedetta; Pende, Daniela; Griffiths, Gillian; Aricò, Maurizio

    2014-01-01

    The human immune system depends on the activity of cytotoxic T lymphocytes (CTL), natural killer (NK) cells, and NKT cells in order to fight off a viral infection. Understanding the molecular mechanisms during this process and the role of individual proteins was greatly improved by the study of familial hemophagocytic lymphohistiocytosis (FHL). Since 1999, genetic sequencing is the gold standard to classify patients into different subgroups of FHL. The diagnosis, once based on a clinical constellation of abnormalities, is now strongly supported by the results of a functional flow-cytometry screening, which directs the genetic study. A few additional congenital immune deficiencies can also cause a resembling or even identical clinical picture to FHL. As in many other rare human disorders, the collection and analysis of a relatively large number of cases in registries is crucial to draw a complete picture of the disease. The conduction of prospective therapeutic trials allows investigators to increase the awareness of the disease and to speed up the diagnostic process, but also provides important functional and genetic confirmations. Children with confirmed diagnosis may undergo hematopoietic stem cell transplantation, which is the only cure known to date. Moreover, detailed characterization of these rare patients helped to understand the function of individual proteins within the exocytic machinery of CTL, NK, and NKT cells. Moreover, identification of these genotypes also provides valuable information on variant phenotypes, other than FHL, associated with biallelic and monoallelic mutations in the FHL-related genes. In this review, we describe how detailed characterization of patients with genetic hemophagocytic lymphohistiocytosis has resulted in improvement in knowledge regarding contribution of individual proteins to the functional machinery of cytotoxic T- and NK-cells. The review also details how identification of these genotypes has provided valuable

  3. The Narrow Niche hypothesis: gray squirrels shed new light on primate origins.

    PubMed

    Orkin, Joseph D; Pontzer, Herman

    2011-04-01

    Current hypotheses for primate origins propose that nails and primate-like grasping hands and feet were important early adaptations for feeding in fine branches. Comparative research in this area has focused on instances of convergence in extant animals, showing that species with primate-like morphology feed predominantly from terminal branches. Little has been done to test whether animals without primate-like morphology engage in similar behavior. We tested the fine-branch niche hypothesis for primate origins by observing branch use in Eastern gray squirrels, Sciurus carolinensis, a species lacking primate grasping adaptations that has been understudied in the context of primate origins. We hypothesized that because gray squirrels lack primate-like grasping adaptations, they would avoid feeding and foraging in terminal branches. Instantaneous focal animal sampling was used to examine the locomotor and postural behaviors used while feeding and foraging. Our results demonstrate habitual and effective usage of terminal branches by gray squirrels while feeding and foraging, primarily on tree seeds (e.g., oak, maple, and elm). Discriminant function analysis indicates that gray squirrels feed and forage like primates, unlike some other tree squirrel species. Given the absence of primate-like features in gray squirrels, we suggest that although selection for fine-branch foraging may be a necessary condition for primate origins, it is not sufficient. We propose an alternative model of primate origins. The Narrow Niche hypothesis suggests that the primate morphological suite evolved not only from selection pressure for fine branch use, but also from a lack of engagement in other activities. PMID:21404237

  4. Efficient event-driven simulations shed new light on microtubule organization in the plant cortical array

    NASA Astrophysics Data System (ADS)

    Tindemans, Simon H.; Deinum, Eva E.; Lindeboom, Jelmer J.; Mulder, Bela M.

    2014-04-01

    The dynamics of the plant microtubule cytoskeleton is a paradigmatic example of the complex spatiotemporal processes characterising life at the cellular scale. This system is composed of large numbers of spatially extended particles, each endowed with its own intrinsic stochastic dynamics, and is capable of non-equilibrium self-organisation through collisional interactions of these particles. To elucidate the behaviour of such a complex system requires not only conceptual advances, but also the development of appropriate computational tools to simulate it. As the number of parameters involved is large and the behaviour is stochastic, it is essential that these simulations be fast enough to allow for an exploration of the phase space and the gathering of sufficient statistics to accurately pin down the average behaviour as well as the magnitude of fluctuations around it. Here we describe a simulation approach that meets this requirement by adopting an event-driven methodology that encompasses both the spontaneous stochastic changes in microtubule state as well as the deterministic collisions. In contrast with finite time step simulations this technique is intrinsically exact, as well as several orders of magnitude faster, which enables ordinary PC hardware to simulate systems of ˜ 10^3 microtubules on a time scale ˜ 10^{3} faster than real time. In addition we present new tools for the analysis of microtubule trajectories on curved surfaces. We illustrate the use of these methods by addressing a number of outstanding issues regarding the importance of various parameters on the transition from an isotropic to an aligned and oriented state.

  5. Shedding light on the relative DNA contribution of two persons handling the same object.

    PubMed

    Oldoni, F; Castella, V; Hall, D

    2016-09-01

    Traces collected on crime scene objects frequently result in challenging DNA mixtures from several contributors in different DNA proportions. Understanding how the relative proportion of DNA deposited by different persons who handled the same object evolves through time has important bearings. For instance, this information may help determine whether the major contributor in a mixed DNA profile is more likely to correspond to the object owner or to the person who may have stolen this object. In this perspective, a simulation-based protocol was designed where randomly paired participants were asked to act either as first (object owner) or second (last) users. The first user was asked to handle/wear 9 different plastic-, metal-, nitrile- and fabric-made objects, commonly found at burglary/robbery crime scenes, for a minimum of 20min during 8 or 10 consecutive days. The second user subsequently used them for 5, 30 or 120min in three distinct simulation sessions. The analysis of the relative DNA contribution on the resulting 234 mock DNA traces revealed a large variability in the contribution depending on the time, substrate and pairs of participants. Despite this, a progressive increase of the second user's DNA contribution, relative to the first user, was observed over time in 93% of the traces. The second user was shown to become the major contributor in approximately 15%, 33% and 55% of the traces recovered from objects used for 5, 30 and 120min, respectively. Single-source DNA profiles were shown to represent only 1% of the traces. In addition, the DNA profiles of 165 out of 234 (71%) simulated traces displayed extra alleles. Most of these occurred in the minor fraction of mixed DNA profiles and were interpreted as artefacts. Nevertheless, DNA profiles of known participants either involved or not in the simulations were observed in 9 cases (4%). This confirms that indirect DNA transfer should be taken into account when interpreting "touch" DNA evidence. PMID

  6. The genomics of wild yeast populations sheds light on the domestication of man's best (micro) friend.

    PubMed

    Eberlein, Chris; Leducq, Jean-Baptiste; Landry, Christian R

    2015-11-01

    The domestication of plants, animals and microbes by humans are the longest artificial evolution experiments ever performed. The study of these long-term experiments can teach us about the genomics of adaptation through the identification of the genetic bases underlying the traits favoured by humans. In laboratory evolution, the characterization of the molecular changes that evolved specifically in some lineages is straightforward because the ancestors are readily available, for instance in the freezer. However, in the case of domesticated species, the ancestor is often missing, which leads to the necessity of going back to nature in order to infer the most likely ancestral state. Significant and relatively recent examples of this approach include wolves as the closest wild relative to domestic dogs (Axelsson et al. 2013) and teosinte as the closest relative to maize (reviewed in Hake & Ross-Ibarra 2015). In both cases, the joint analysis of domesticated lineages and their wild cousins has been key in reconstructing the molecular history of their domestication. While the identification of closest wild relatives has been done for many plants and animals, these comparisons represent challenges for micro-organisms. This has been the case for the budding yeast Saccharomyces cerevisiae, whose natural ecological niche is particularly challenging to define. For centuries, this unicellular fungus has been the cellular factory for wine, beer and bread crafting, and currently for bioethanol and drug production. While the recent development of genomics has lead to the identification of many genetic elements associated with important wine characteristics, the historical origin of some of the domesticated wine strains has remained elusive due to the lack of knowledge of their close wild relatives. In this issue of Molecular Ecology, Almeida et al. (2015) identified what is to date the closest known wild population of the wine yeast. This population is found associated with

  7. The metabolic responses to hepatitis B virus infection shed new light on pathogenesis and targets for treatment

    PubMed Central

    Li, Hongde; Zhu, Wandi; Zhang, Leike; Lei, Hehua; Wu, Xiangyu; Guo, Lin; Chen, Xinwen; Wang, Yulan; Tang, Huiru

    2015-01-01

    Chronic infection caused by the hepatitis B virus (HBV), is strongly associated with hepatitis, fatty liver and hepatocellular carcinoma. To investigate the underlying mechanisms, we characterize the metabolic features of host cells infected with the virus using systems biological approach. The results show that HBV replication induces systematic metabolic alterations in host cells. HBV infection up-regulates the biosynthesis of hexosamine and phosphatidylcholine by activating glutamine-fructose-6-phosphate amidotransferase 1 (GFAT1) and choline kinase alpha (CHKA) respectively, which were reported for the first time for HBV infection. Importantly suppressing hexosamine biosynthesis and phosphatidylcholine biosynthesis can inhibit HBV replication and expression. In addition, HBV induces oxidative stress and stimulates central carbon metabolism and nucleotide synthesis. Our results also indicate that HBV associated hepatocellular carcinoma could be attributed to GFAT1 activated hexosamine biosynthesis and CHKA activated phosphatidylcholine biosynthesis. This study provides further insights into the pathogenesis of HBV-induced diseases, and sheds new light on drug target for treating HBV infection. PMID:25672227

  8. Crystal structures of a Populus tomentosa 4-coumarate:CoA ligase shed light on its enzymatic mechanisms.

    PubMed

    Hu, Yonglin; Gai, Ying; Yin, Lei; Wang, Xiaoxue; Feng, Chunyan; Feng, Lei; Li, Defeng; Jiang, Xiang-Ning; Wang, Da-Cheng

    2010-09-01

    4-Coumaric acid:CoA ligase (4CL) is the central enzyme of the plant-specific phenylpropanoid pathway. It catalyzes the synthesis of hydroxycinnamate-CoA thioesters, the precursors of lignin and other important phenylpropanoids, in two-step reactions involving the formation of hydroxycinnamate-AMP anhydride and then the nucleophilic substitution of AMP by CoA. In this study, we determined the crystal structures of Populus tomentosa 4CL1 in the unmodified (apo) form and in forms complexed with AMP and adenosine 5'-(3-(4-hydroxyphenyl)propyl)phosphate (APP), an intermediate analog, at 2.4, 2.5, and 1.9 Å resolution, respectively. 4CL1 consists of two globular domains connected by a flexible linker region. The larger N-domain contains a substrate binding pocket, while the C-domain contains catalytic residues. Upon binding of APP, the C-domain rotates 81° relative to the N-domain. The crystal structure of 4CL1-APP reveals its substrate binding pocket. We identified residues essential for catalytic activities (Lys-438, Gln-443, and Lys-523) and substrate binding (Tyr-236, Gly-306, Gly-331, Pro-337, and Val-338) based on their crystal structures and by means of mutagenesis and enzymatic activity studies. We also demonstrated that the size of the binding pocket is the most important factor in determining the substrate specificities of 4CL1. These findings shed light on the enzymatic mechanisms of 4CLs and provide a solid foundation for the bioengineering of these enzymes. PMID:20841425

  9. Shedding Light on Avian Influenza H4N6 Infection in Mallards: Modes of Transmission and Implications for Surveillance

    PubMed Central

    VanDalen, Kaci K.; Franklin, Alan B.; Mooers, Nicole L.; Sullivan, Heather J.; Shriner, Susan A.

    2010-01-01

    Background Wild mallards (Anas platyrhychos) are considered one of the primary reservoir species for avian influenza viruses (AIV). Because AIV circulating in wild birds pose an indirect threat to agriculture and human health, understanding the ecology of AIV and developing risk assessments and surveillance systems for prevention of disease is critical. Methodology/Principal Findings In this study, mallards were experimentally infected with an H4N6 subtype of AIV by oral inoculation or contact with an H4N6 contaminated water source. Cloacal swabs, oropharyngeal swabs, fecal samples, and water samples were collected daily and tested by real-time RT-PCR (RRT-PCR) for estimation of viral shedding. Fecal samples had significantly higher virus concentrations than oropharyngeal or cloacal swabs and 6 month old ducks shed significantly more viral RNA than 3 month old ducks regardless of sample type. Use of a water source contaminated by AIV infected mallards, was sufficient to transmit virus to naïve mallards, which shed AIV at higher or similar levels as orally-inoculated ducks. Conclusions Bodies of water could serve as a transmission pathway for AIV in waterfowl. For AIV surveillance purposes, water samples and fecal samples appear to be excellent alternatives or additions to cloacal and oropharyngeal swabbing. Furthermore, duck age (even within hatch-year birds) may be important when interpreting viral shedding results from experimental infections or surveillance. Differential shedding among hatch-year mallards could affect prevalence estimates, modeling of AIV spread, and subsequent risk assessments. PMID:20877466

  10. NASA Lighting Research, Test, & Analysis

    NASA Technical Reports Server (NTRS)

    Clark, Toni

    2015-01-01

    The Habitability and Human Factors Branch, at Johnson Space Center, in Houston, TX, provides technical guidance for the development of spaceflight lighting requirements, verification of light system performance, analysis of integrated environmental lighting systems, and research of lighting-related human performance issues. The Habitability & Human Factors Lighting Team maintains two physical facilities that are integrated to provide support. The Lighting Environment Test Facility (LETF) provides a controlled darkroom environment for physical verification of lighting systems with photometric and spetrographic measurement systems. The Graphics Research & Analysis Facility (GRAF) maintains the capability for computer-based analysis of operational lighting environments. The combined capabilities of the Lighting Team at Johnson Space Center have been used for a wide range of lighting-related issues.

  11. Proper orthogonal decomposition analysis of vortex shedding behind a rotating circular cylinder

    NASA Astrophysics Data System (ADS)

    Sham Dol, Sharul

    2016-03-01

    Turbulence studies were made in the wake of a rotating circular cylinder in a uniform free stream with the objective of describing the patterns of the vortex shedding up to suppression of the periodic vortex street at high velocity ratios, λ. The results obtained in the present study establish that shedding of Kármán vortices in a rotating circular cylinder-generated wake is modified by rotation of the cylinder. Alternate vortex shedding is highly visible when λ < 2.0 although the strength of the separated shear layers differ due to the rotation of the cylinder. The spectral density in the wakes indicate significant changes at λ = 2.0. The results indicate that the rotation of the cylinder causes significant disruption in the structure of the flow. Alternate vortex shedding is weak, distorted and close to being suppressed at λ = 2.0. It is clear that flow asymmetries will weaken vortex shedding, and when the asymmetries are significant enough, total suppression of a periodic street occurs. Particular attention was paid to the decomposition of the flow using Proper Orthogonal Decomposition (POD). By analyzing this decomposition with the help of Particle Image Velocimetry (PIV )data, it was found that large scales contribute to the coherent motion. Vorticity structures in the modes become increasingly irregular with downstream distance, suggesting turbulent interactions are occurring at the more downstream locations, especially when the cylinder rotates.

  12. Studies of Human 2,4-Dienoyl CoA Reductase Shed New Light on Peroxisomal β-Oxidation of Unsaturated Fatty Acids

    SciTech Connect

    Hua, Tian; Wu, Dong; Ding, Wei; Wang, Jiangyun; Shaw, Neil; Liu, Zhi-Jie

    2012-10-15

    Peroxisomes play an essential role in maintaining fatty acid homeostasis. Although mitochondria are also known to participate in the catabolism of fatty acids via β-oxidation, differences exist between the peroxisomal and mitochondrial β-oxidation. Only peroxisomes, but not mitochondrion, can shorten very long chain fatty acids. Here, we describe the crystal structure of a ternary complex of peroxisomal 2,4-dienoyl CoA reductases (pDCR) with hexadienoyl CoA and NADP, as a prototype for comparison with the mitochondrial 2,4-dienoyl CoA reductase (mDCR) to shed light on the differences between the enzymes from the two organelles at the molecular level. Unexpectedly, the structure of pDCR refined to 1.84 Å resolution reveals the absence of the tyrosine-serine pair seen in the active site of mDCR, which together with a lysine and an asparagine have been deemed a hallmark of the SDR family of enzymes. Instead, aspartate hydrogen-bonded to the Cα hydroxyl via a water molecule seems to perturb the water molecule for protonation of the substrate. Our studies provide the first structural evidence for participation of water in the DCR-catalyzed reactions. Biochemical studies and structural analysis suggest that pDCRs can catalyze the shortening of six-carbon-long substrates in vitro. However, the Km values of pDCR for short chain acyl CoAs are at least 6-fold higher than those for substrates with 10 or more aliphatic carbons. Unlike mDCR, hinge movements permit pDCR to process very long chain polyunsaturated fatty acids.

  13. Stray Light Analysis

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Based on a Small Business Innovation Research contract from the Jet Propulsion Laboratory, TracePro is state-of-the-art interactive software created by Lambda Research Corporation to detect stray light in optical systems. An image can be ruined by incidental light in an optical system. To maintain image excellence from an optical system, stray light must be detected and eliminated. TracePro accounts for absorption, specular reflection and refraction, scattering and aperture diffraction of light. Output from the software consists of spatial irradiance plots and angular radiance plots. Results can be viewed as contour maps or as ray histories in tabular form. TracePro is adept at modeling solids such as lenses, baffles, light pipes, integrating spheres, non-imaging concentrators, and complete illumination systems. The firm's customer base includes Lockheed Martin, Samsung Electronics and other manufacturing, optical, aerospace, and educational companies worldwide.

  14. SIRTF stray light analysis

    NASA Technical Reports Server (NTRS)

    Elliott, David G.; Dinger, Ann S.

    1991-01-01

    The Space Infrared Telescope Facility (SIRTF) is a 1-meter cryogenic infrared telescope. Stray light is kept below the natural background by restrictions on sun, Earth, and moon off-axis angles; by conservative baffle design; by the use of advanced diffuse black coatings; and by superfluid helium cooling. The aperture stop is located at the primary mirror rather than at the secondary mirror to increase the aperture and reduce the central obscuration. Stray light from off-axis sources is greater with the aperture stop at the primary than with the aperture stop at the secondary, but the modulation of the signal produced by tilting of the secondary mirror for chopping is less. Stray light from telescope thermal emission is lower with the aperture stop at the primary.

  15. Light intensity strain analysis

    NASA Technical Reports Server (NTRS)

    Williams, J. G. (Inventor)

    1973-01-01

    A process is described for the analysis of the strain field of structures subjected to large deformations involving a low modulus substrate having a high modulus, relatively thin coating. The optical properties of transmittance and reflectance are measured for the coated substrate while stressed and unstressed to indicate the strain field for the coated substrate.

  16. Femtosecond transient infrared and stimulated Raman spectroscopy shed light on the relaxation mechanisms of photo-excited peridinin

    NASA Astrophysics Data System (ADS)

    Di Donato, Mariangela; Ragnoni, Elena; Lapini, Andrea; Foggi, Paolo; Hiller, Roger G.; Righini, Roberto

    2015-06-01

    By means of one- and two-dimensional transient infrared spectroscopy and femtosecond stimulated Raman spectroscopy, we investigated the excited state dynamics of peridinin, a carbonyl carotenoid occurring in natural light harvesting complexes. The presence of singly and doubly excited states, as well as of an intramolecular charge transfer (ICT) state, makes the behavior of carbonyl carotenoids in the excited state very complex. In this work, we investigated by time resolved spectroscopy the relaxation of photo-excited peridinin in solvents of different polarities and as a function of the excitation wavelength. Our experimental results show that a characteristic pattern of one- and two-dimensional infrared bands in the C=C stretching region allows monitoring the relaxation pathway. In polar solvents, moderate distortions of the molecular geometry cause a variation of the single/double carbon bond character, so that the partially ionic ICT state is largely stabilized by the solvent reorganization. After vertical photoexcitation at 400 nm of the S2 state, the off-equilibrium population moves to the S1 state with ca. 175 fs time constant; from there, in less than 5 ps, the non-Franck Condon ICT state is reached, and finally, the ground state is recovered in 70 ps. That the relevant excited state dynamics takes place far from the Franck Condon region is demonstrated by its noticeable dependence on the excitation wavelength.

  17. Transcriptome comparisons shed light on the pre-condition and potential barrier for C4 photosynthesis evolution in eudicots.

    PubMed

    Tao, Yimin; Lyu, Ming-Ju Amy; Zhu, Xin-Guang

    2016-05-01

    C4 photosynthesis evolved independently from C3 photosynthesis in more than 60 lineages. Most of the C4 lineages are clustered together in the order Poales and the order Caryophyllales while many other angiosperm orders do not have C4 species, suggesting the existence of biological pre-conditions in the ancestral C3 species that facilitate the evolution of C4 photosynthesis in these lineages. To explore pre-adaptations for C4 photosynthesis evolution, we classified C4 lineages into the C4-poor and the C4-rich groups based on the percentage of C4 species in different genera and conducted a comprehensive comparison on the transcriptomic changes between the non-C4 species from the C4-poor and the C4-rich groups. Results show that species in the C4-rich group showed higher expression of genes related to oxidoreductase activity, light reaction components, terpene synthesis, secondary cell synthesis, C4 cycle related genes and genes related to nucleotide metabolism and senescence. In contrast, C4-poor group showed up-regulation of a PEP/Pi translocator, genes related to signaling pathway, stress response, defense response and plant hormone metabolism (ethylene and brassinosteroid). The implications of these transcriptomic differences between the C4-rich and C4-poor groups to C4 evolution are discussed. PMID:26893123

  18. Analysis of the pathogenetic basis for shedding and transmission of ovine gamma herpesvirus 2.

    PubMed

    Hüssy, Daniela; Janett, Fredi; Albini, Sarah; Stäuber, Norbert; Thun, Rico; Ackermann, Mathias

    2002-12-01

    Ovine herpesvirus 2 (OvHV-2), a member of the viral subfamily Gammaherpesvirinae, shares numerous similarities with human herpesvirus 8 (HHV-8). Both viruses are apathogenic in their healthy original host, may cause lymphoprolipherative diseases, cannot routinely be propagated in cell culture, and may be sexually transmitted. However, the pathways of sexual transmission of these viruses, as well as the underlying pathogenetic dynamics, are not well understood. Organs from naturally OvHV-2-infected, as well as OvHV-2-free, sheep were quantitatively analyzed for OvHV-2 by the DNA amplification techniques. The dynamics of OvHV-2 multiplication and excretion were monitored after experimental infections and, most importantly, subsequent to vasectomy. The OvHV-2 DNA load in various tissues and internal organs was not merely reflecting the viral DNA load in the bloodstream, which suggested compartmentalization of OvHV-2. Moreover, OvHV-2 DNA was detected at several portals for virus shedding, i.e., the respiratory, alimentary, and urogenital tracts. Transient OvHV-2 excretion was detected in ejaculates of experimentally infected rams. Upon vasectomy, OvHV-2 DNA reappeared in the ejaculatory plasma, but the titers did not decline after reaching a peak. Spiking and fractionation experiments revealed an inhibitory activity, associated with the spermatozoa, which was able to suppress detection of viral DNA but which was no longer present in samples from vasectomized animals. Therefore, epidemiological studies on viruses that may be transmitted by the ejaculatory pathway and for whose tracing nucleic acid amplification methods are used, i.e., OvHV-2, HHV-8, and the human immunodeficiency virus, should include vasectomized males. PMID:12454175

  19. Analysis of the Pathogenetic Basis for Shedding and Transmission of Ovine Gamma Herpesvirus 2

    PubMed Central

    Hüssy, Daniela; Janett, Fredi; Albini, Sarah; Stäuber, Norbert; Thun, Rico; Ackermann, Mathias

    2002-01-01

    Ovine herpesvirus 2 (OvHV-2), a member of the viral subfamily Gammaherpesvirinae, shares numerous similarities with human herpesvirus 8 (HHV-8). Both viruses are apathogenic in their healthy original host, may cause lymphoprolipherative diseases, cannot routinely be propagated in cell culture, and may be sexually transmitted. However, the pathways of sexual transmission of these viruses, as well as the underlying pathogenetic dynamics, are not well understood. Organs from naturally OvHV-2-infected, as well as OvHV-2-free, sheep were quantitatively analyzed for OvHV-2 by the DNA amplification techniques. The dynamics of OvHV-2 multiplication and excretion were monitored after experimental infections and, most importantly, subsequent to vasectomy. The OvHV-2 DNA load in various tissues and internal organs was not merely reflecting the viral DNA load in the bloodstream, which suggested compartmentalization of OvHV-2. Moreover, OvHV-2 DNA was detected at several portals for virus shedding, i.e., the respiratory, alimentary, and urogenital tracts. Transient OvHV-2 excretion was detected in ejaculates of experimentally infected rams. Upon vasectomy, OvHV-2 DNA reappeared in the ejaculatory plasma, but the titers did not decline after reaching a peak. Spiking and fractionation experiments revealed an inhibitory activity, associated with the spermatozoa, which was able to suppress detection of viral DNA but which was no longer present in samples from vasectomized animals. Therefore, epidemiological studies on viruses that may be transmitted by the ejaculatory pathway and for whose tracing nucleic acid amplification methods are used, i.e., OvHV-2, HHV-8, and the human immunodeficiency virus, should include vasectomized males. PMID:12454175

  20. Inferred L/M cone opsin polymorphism of ancestral tarsiers sheds dim light on the origin of anthropoid primates

    PubMed Central

    Melin, Amanda D.; Matsushita, Yuka; Moritz, Gillian L.; Dominy, Nathaniel J.; Kawamura, Shoji

    2013-01-01

    Tarsiers are small nocturnal primates with a long history of fuelling debate on the origin and evolution of anthropoid primates. Recently, the discovery of M and L opsin genes in two sister species, Tarsius bancanus (Bornean tarsier) and Tarsius syrichta (Philippine tarsier), respectively, was interpreted as evidence of an ancestral long-to-middle (L/M) opsin polymorphism, which, in turn, suggested a diurnal or cathemeral (arrhythmic) activity pattern. This view is compatible with the hypothesis that stem tarsiers were diurnal; however, a reversion to nocturnality during the Middle Eocene, as evidenced by hyper-enlarged orbits, predates the divergence of T. bancanus and T. syrichta in the Late Miocene. Taken together, these findings suggest that some nocturnal tarsiers possessed high-acuity trichromatic vision, a concept that challenges prevailing views on the adaptive origins of the anthropoid visual system. It is, therefore, important to explore the plausibility and antiquity of trichromatic vision in the genus Tarsius. Here, we show that Sulawesi tarsiers (Tarsius tarsier), a phylogenetic out-group of Philippine and Bornean tarsiers, have an L opsin gene that is more similar to the L opsin gene of T. syrichta than to the M opsin gene of T. bancanus in non-synonymous nucleotide sequence. This result suggests that an L/M opsin polymorphism is the ancestral character state of crown tarsiers and raises the possibility that many hallmarks of the anthropoid visual system evolved under dim (mesopic) light conditions. This interpretation challenges the persistent nocturnal–diurnal dichotomy that has long informed debate on the origin of anthropoid primates. PMID:23536597

  1. Shedding new light on historical metal samples using micro-focused synchrotron X-ray fluorescence and spectroscopy

    NASA Astrophysics Data System (ADS)

    Grolimund, D.; Senn, M.; Trottmann, M.; Janousch, M.; Bonhoure, I.; Scheidegger, A. M.; Marcus, M.

    2004-10-01

    insights concerning the nature and origin of used raw materials as well as regarding employed processing techniques during historic iron fabrication and weapon manufacturing.The study demonstrates the potential of oxidation state and mineral phase mapping based on energy selective micro-XRF maps and spectroscopic phase identification. Such a spatially resolved recording of the chemical speciation is based on X-ray absorption spectroscopy. This analytical technique is exclusive to synchrotron light sources. However, the steadily increasing number of available synchrotron-based X-ray microprobes allows nowadays for more routine utilization of such micro-XAS techniques.

  2. Shedding Light on the Etiology of Sports Injuries: A Look Behind the Scenes of Time-to-Event Analyses.

    PubMed

    Nielsen, Rasmus Østergaard; Malisoux, Laurent; Møller, Merete; Theisen, Daniel; Parner, Erik Thorlund

    2016-04-01

    Synopsis The etiological mechanism underpinning any sports-related injury is complex and multifactorial. Frequently, athletes perceive "excessive training" as the principal factor in their injury, an observation that is biologically plausible yet somewhat ambiguous. If the applied training load is suddenly increased, this may increase the risk for sports injury development, irrespective of the absolute amount of training. Indeed, little to no rigorous scientific evidence exists to support the hypothesis that fluctuations in training load, compared to absolute training load, are more important in explaining sports injury development. One reason for this could be that prospective data from scientific studies should be analyzed in a different manner. Time-to-event analysis is a useful statistical tool in which to analyze the influence of changing exposures on injury risk. However, the potential of time-to-event analysis remains insufficiently exploited in sports injury research. Therefore, the purpose of the present article was to present and discuss measures of association used in time-to-event analyses and to present the advanced concept of time-varying exposures and outcomes. In the paper, different measures of association, such as cumulative relative risk, cumulative risk difference, and the classical hazard rate ratio, are presented in a nontechnical manner, and suggestions for interpretation of study results are provided. To summarize, time-to-event analysis complements the statistical arsenal of sports injury prevention researchers, because it enables them to analyze the complex and highly dynamic reality of injury etiology, injury recurrence, and time to recovery across a range of sporting contexts. J Orthop Sports Phys Ther 2016;46(4):300-311. Epub 8 Mar 2016. doi:10.2519/jospt.2016.6510. PMID:26954269

  3. Multiple lines of evidence shed light on the occurrence of paramecium (ciliophora, oligohymenophorea) in bromeliad tank water.

    PubMed

    Buosi, Paulo R B; Cabral, Adalgisa F; Simão, Taiz L L; Utz, Laura R P; Velho, Luiz F M

    2014-01-01

    Phytotelmata are vegetal structures that hold water from the rain, and organic matter from the forest and the soil, resulting in small, compartmentalized bodies of water, which provide an essential environment for the establishment and development of many organisms. These microenvironments generally harbor endemic species, but many organisms that are found in lakes and rivers, are also present. Here, we report, for the first time, the occurrence of the ciliate genus Paramecium in the tank of the bromeliad species Aechmaea distichantha. The identification of the Paramecium species was performed based on live observations, protargol impregnation, scanning electronic microscopy, and sequencing of the 18s rRNA. The absence of Paramecium from bromeliad tank water was highlighted in several earlier investigations, and may be due to the fact that this species is unable to make cysts. The occurrence of Paramecium multimicronucleatum in our samples may be explained by the proximity between the bromeliads and the river, a potential source of the species. Further, we also believe that the counting methodology used in our study provides a more accurate analysis of the species diversity, since we investigated all samples within a maximum period of 6 h after sampling, allowing minimum loss of specimens. PMID:24011017

  4. Population genomics shed light on the demographic and adaptive histories of European invasion in the Pacific oyster, Crassostrea gigas

    PubMed Central

    Rohfritsch, Audrey; Bierne, Nicolas; Boudry, Pierre; Heurtebise, Serge; Cornette, Florence; Lapègue, Sylvie

    2013-01-01

    Crassostrea gigas originated from the Pacific coast of Asia, but was introduced into several European countries in the early 1970s. Natural populations have now spread across the length of the western seaboard of Europe. To elucidate the demographic and selective processes at play during this rapid expansion, genome-scan analysis was performed on different populations. High diversities and low differentiation were observed overall, but significant genetic differentiation was found among newly established populations and between the newly established northern group and a nearly panmictic group composed of southern European populations and a population from Japan. Loss of genetic diversity was also seen in the north, likely caused by founder events during colonization. The few strongly supported outlier loci revealed a genetic structure uncorrelated with the north/south differentiation, but grouping two samples from the Danish fjords (northern group) and one from the Dutch Scheldt estuary (southern group) with the one from Japan. These findings might reflect the following: (i) parallel adaptation to similar environmental pressures (fjord-like environment) within each of the two groups or (ii) a footprint of a secondary introduction of an alternative genomic background maintained by multifarious isolation factors. Our results call for a closer examination of adaptive genetic structure in the area of origin. PMID:24187588

  5. Shedding Some Light over the Floral Metabolism by Arum Lily (Zantedeschia aethiopica) Spathe De Novo Transcriptome Assembly

    PubMed Central

    Cândido, Elizabete de Souza; Fernandes, Gabriel da Rocha; de Alencar, Sérgio Amorim; Cardoso, Marlon Henrique e Silva; Lima, Stella Maris de Freitas; Miranda, Vívian de Jesus; Porto, William Farias; Nolasco, Diego Oliveira; de Oliveira-Júnior, Nelson Gomes; Barbosa, Aulus Estevão Anjos de Deus; Pogue, Robert Edward; Rezende, Taia Maria Berto; Dias, Simoni Campos; Franco, Octávio Luiz

    2014-01-01

    Zantedeschia aethiopica is an evergreen perennial plant cultivated worldwide and commonly used for ornamental and medicinal purposes including the treatment of bacterial infections. However, the current understanding of molecular and physiological mechanisms in this plant is limited, in comparison to other non-model plants. In order to improve understanding of the biology of this botanical species, RNA-Seq technology was used for transcriptome assembly and characterization. Following Z. aethiopica spathe tissue RNA extraction, high-throughput RNA sequencing was performed with the aim of obtaining both abundant and rare transcript data. Functional profiling based on KEGG Orthology (KO) analysis highlighted contigs that were involved predominantly in genetic information (37%) and metabolism (34%) processes. Predicted proteins involved in the plant circadian system, hormone signal transduction, secondary metabolism and basal immunity are described here. In silico screening of the transcriptome data set for antimicrobial peptide (AMP) –encoding sequences was also carried out and three lipid transfer proteins (LTP) were identified as potential AMPs involved in plant defense. Spathe predicted protein maps were drawn, and suggested that major plant efforts are expended in guaranteeing the maintenance of cell homeostasis, characterized by high investment in carbohydrate, amino acid and energy metabolism as well as in genetic information. PMID:24614014

  6. Single-molecule colocalization studies shed light on the idea of fully emitting versus dark single quantum dots.

    PubMed

    Pons, Thomas; Medintz, Igor L; Farrell, Dorothy; Wang, Xiang; Grimes, Amy F; English, Douglas S; Berti, Lorenzo; Mattoussi, Hedi

    2011-07-18

    In this report the correlation between the solution photoluminescence (PL) quantum yield and the fluorescence emission of individual semiconductor quantum dots (QDs) is investigated. This is done by taking advantage of previously reported enhancement in the macroscopic quantum yield of water-soluble QDs capped with dihydrolipoic acid (DHLA) when self-assembled with polyhistidine-appended proteins, and by using fluorescence coincidence analysis (FCA) to detect the presence of "bright" and "dark" single QDs in solution. This allows for changes in the fraction of the two QD species to be tracked as the PL yield of the solution is progressively altered. The results clearly indicate that in a dispersion of luminescent nanocrystals, "bright" (intermittently emitting) single QDs coexist with "permanently dark" (non-emitting) QDs. Furthermore, the increase in the fraction of emitting QDs accompanies the increase in the PL quantum yield of the solution. These findings support the idea that a dispersion of QDs consists of two optically distinct populations of nanocrystals--one is "bright" while the other is "dark;" and that the relative fraction of these two populations defines the overall PL yield. PMID:21710484

  7. A physical map for the Amborella trichopoda genome sheds light on the evolution of angiosperm genome structure

    PubMed Central

    2011-01-01

    Background Recent phylogenetic analyses have identified Amborella trichopoda, an understory tree species endemic to the forests of New Caledonia, as sister to a clade including all other known flowering plant species. The Amborella genome is a unique reference for understanding the evolution of angiosperm genomes because it can serve as an outgroup to root comparative analyses. A physical map, BAC end sequences and sample shotgun sequences provide a first view of the 870 Mbp Amborella genome. Results Analysis of Amborella BAC ends sequenced from each contig suggests that the density of long terminal repeat retrotransposons is negatively correlated with that of protein coding genes. Syntenic, presumably ancestral, gene blocks were identified in comparisons of the Amborella BAC contigs and the sequenced Arabidopsis thaliana, Populus trichocarpa, Vitis vinifera and Oryza sativa genomes. Parsimony mapping of the loss of synteny corroborates previous analyses suggesting that the rate of structural change has been more rapid on lineages leading to Arabidopsis and Oryza compared with lineages leading to Populus and Vitis. The gamma paleohexiploidy event identified in the Arabidopsis, Populus and Vitis genomes is shown to have occurred after the divergence of all other known angiosperms from the lineage leading to Amborella. Conclusions When placed in the context of a physical map, BAC end sequences representing just 5.4% of the Amborella genome have facilitated reconstruction of gene blocks that existed in the last common ancestor of all flowering plants. The Amborella genome is an invaluable reference for inferences concerning the ancestral angiosperm and subsequent genome evolution. PMID:21619600

  8. The mitochondrial genome of Hydra oligactis (Cnidaria, Hydrozoa) sheds new light on animal mtDNA evolution and cnidarian phylogeny.

    PubMed

    Kayal, Ehsan; Lavrov, Dennis V

    2008-02-29

    The 16,314-nuceotide sequence of the linear mitochondrial DNA (mtDNA) molecule of Hydra oligactis (Cnidaria, Hydrozoa)--the first from the class Hydrozoa--has been determined. This sequence contains genes for 13 energy pathway proteins, small and large subunit rRNAs, and methionine and tryptophan tRNAs, as is typical for cnidarians. All genes have the same transcriptional orientation and their arrangement in the genome is similar to that of the jellyfish Aurelia aurita. In addition, a partial copy of cox1 is present at one end of the molecule in a transcriptional orientation opposite to the rest of the genes, forming a part of inverted terminal repeat characteristic of linear mtDNA and linear mitochondrial plasmids. The sequence close to at least one end of the molecule contains several homonucleotide runs as well as small inverted repeats that are able to form strong secondary structures and may be involved in mtDNA maintenance and expression. Phylogenetic analysis of mitochondrial genes of H. oligactis and other cnidarians supports the Medusozoa hypothesis but also suggests that Anthozoa may be paraphyletic, with octocorallians more closely related to the Medusozoa than to the Hexacorallia. The latter inference implies that Anthozoa is paraphyletic and that the polyp (rather than a medusa) is the ancestral body type in Cnidaria. PMID:18222615

  9. A novel in vivo cell-wall labeling approach sheds new light on peptidoglycan synthesis in Escherichia coli.

    PubMed

    Olrichs, Nick K; Aarsman, Mirjam E G; Verheul, Jolanda; Arnusch, Christopher J; Martin, Nathaniel I; Hervé, Mireille; Vollmer, Waldemar; de Kruijff, Ben; Breukink, Eefjan; den Blaauwen, Tanneke

    2011-05-01

    Peptidoglycan synthesis and turnover in relation to cell growth and division has been studied by using a new labeling method. This method involves the incorporation of fluorescently labeled peptidoglycan precursors into the cell wall by means of the cell-wall recycling pathway. We show that Escherichia coli is able to import exogenous added murein tripeptide labeled with N-7-nitro-2,1,3-benzoxadiazol-4-yl (AeK-NBD) into the cytoplasm where it enters the peptidoglycan biosynthesis route, resulting in fluorescent labels specifically located in the cell wall. When wild-type cells were grown in the presence of the fluorescent peptide, peptidoglycan was uniformly labeled in cells undergoing elongation. Cells in the process of division displayed a lack of labeled peptidoglycan at mid-cell. Analysis of labeling patterns in cell division mutants showed that the occurrence of unlabeled peptidoglycan is dependent on the presence of FtsZ, but independent of FtsQ and FtsI. Accumulation of fluorescence at the division sites of a triple amidase mutant (ΔamiABC) revealed that AeK-NBD is incorporated into septal peptidoglycan. AmiC was shown to be involved in the rapid removal of labeled peptidoglycan side chains at division sites in wild-type cells. Because septal localization of AmiC is dependent on FtsQ and FtsI, this points to the presence of another peptidoglycan hydrolase activity directly dependent on FtsZ. PMID:21472954

  10. Novel parvoviruses in reptiles and genome sequence of a lizard parvovirus shed light on Dependoparvovirus genus evolution.

    PubMed

    Pénzes, Judit J; Pham, Hanh T; Benkö, Mária; Tijssen, Peter

    2015-09-01

    Here, we report the detection and partial genome characterization of two novel reptilian parvoviruses derived from a short-tailed pygmy chameleon (Rampholeon brevicaudatus) and a corn snake (Pantherophis guttatus) along with the complete genome analysis of the first lizard parvovirus, obtained from four bearded dragons (Pogona vitticeps). Both homology searches and phylogenetic tree reconstructions demonstrated that all are members of the genus Dependoparvovirus. Even though most dependoparvoviruses replicate efficiently only in co-infections with large DNA viruses, no such agents could be detected in one of the bearded dragon samples, hence the possibility of autonomous replication was explored. The alternative ORF encoding the full assembly activating protein (AAP), typical for the genus, could be obtained from reptilian parvoviruses for the first time, with a structure that appears to be more ancient than that of avian and mammalian parvoviruses. All three viruses were found to harbour short introns as previously observed for snake adeno-associated virus, shorter than that of any non-reptilian dependoparvovirus. According to the phylogenetic calculations based on full non-structural protein (Rep) and AAP sequences, the monophyletic cluster of reptilian parvoviruses seems to be the most basal out of all lineages of genus Dependoparvovirus. The suspected ability for autonomous replication, results of phylogenetic tree reconstruction, intron lengths and the structure of the AAP suggested that a single Squamata origin instead of the earlier assumed diapsid (common avian-reptilian) origin is more likely for the genus Dependoparvovirus of the family Parvoviridae. PMID:26067293

  11. Synchrotron-Based Techniques Shed Light on Mechanisms of Plant Sensitivity and Tolerance to High Manganese in the Root Environment.

    PubMed

    Blamey, F Pax C; Hernandez-Soriano, Maria C; Cheng, Miaomiao; Tang, Caixian; Paterson, David J; Lombi, Enzo; Wang, Wei Hong; Scheckel, Kirk G; Kopittke, Peter M

    2015-11-01

    Plant species differ in response to high available manganese (Mn), but the mechanisms of sensitivity and tolerance are poorly understood. In solution culture, greater than or equal to 30 µm Mn decreased the growth of soybean (Glycine max), but white lupin (Lupinus albus), narrow-leafed lupin (Lupin angustifolius), and sunflower (Helianthus annuus) grew well at 100 µm Mn. Differences in species' tolerance to high Mn could not be explained simply by differences in root, stem, or leaf Mn status, being 8.6, 17.1, 6.8, and 9.5 mmol kg(-1) leaf fresh mass at 100 µm Mn. Furthermore, x-ray absorption near edge structure analyses identified the predominance of Mn(II), bound mostly to malate or citrate, in roots and stems of all four species. Rather, differences in tolerance were due to variations in Mn distribution and speciation within leaves. In Mn-sensitive soybean, in situ analysis of fresh leaves using x-ray fluorescence microscopy combined with x-ray absorption near edge structure showed high Mn in the veins, and manganite [Mn(III)] accumulated in necrotic lesions apparently through low Mn sequestration in vacuoles or other vesicles. In the two lupin species, most Mn accumulated in vacuoles as either soluble Mn(II) malate or citrate. In sunflower, Mn was sequestered as manganite at the base of nonglandular trichomes. Hence, tolerance to high Mn was ascribed to effective sinks for Mn in leaves, as Mn(II) within vacuoles or through oxidation of Mn(II) to Mn(III) in trichomes. These two mechanisms prevented Mn accumulation in the cytoplasm and apoplast, thereby ensuring tolerance to high Mn in the root environment. PMID:26395840

  12. The genome sequence of Brucella pinnipedialis B2/94 sheds light on the evolutionary history of the genus Brucella

    PubMed Central

    2011-01-01

    Background Since the discovery of the Malta fever agent, Brucella melitensis, in the 19th century, six terrestrial mammal-associated Brucella species were recognized over the next century. More recently the number of novel Brucella species has increased and among them, isolation of species B. pinnipedialis and B. ceti from marine mammals raised many questions about their origin as well as on the evolutionary history of the whole genus. Results We report here on the first complete genome sequence of a Brucella strain isolated from marine mammals, Brucella pinnipedialis strain B2/94. A whole gene-based phylogenetic analysis shows that five main groups of host-associated Brucella species rapidly diverged from a likely free-living ancestor close to the recently isolated B. microti. However, this tree lacks the resolution required to resolve the order of divergence of those groups. Comparative analyses focusing on a) genome segments unshared between B. microti and B. pinnipedialis, b) gene deletion/fusion events and c) positions and numbers of Brucella specific IS711 elements in the available Brucella genomes provided enough information to propose a branching order for those five groups. Conclusions In this study, it appears that the closest relatives of marine mammal Brucella sp. are B. ovis and Brucella sp. NVSL 07-0026 isolated from a baboon, followed by B. melitensis and B. abortus strains, and finally the group consisting of B. suis strains, including B. canis and the group consisting of the single B. neotomae species. We were not able, however, to resolve the order of divergence of the two latter groups. PMID:21745361

  13. Analysis of Phosphorus Flows through Minnesota's Twin Cities Urban Food-Shed: Three Scenarios for Improving Nutrient Efficiency

    NASA Astrophysics Data System (ADS)

    Peterson, H. M.; Baker, L. A.

    2012-12-01

    Phosphorus (P) is a non-renewable resource, essential for agriculture and human food production. Although it is being depleted globally, urban P use is inefficient and contributes to water resources degradation, particularly accelerated eutrophication of receiving waters. A paradox in the P cycle is that although P enters the system through fertilizer application to agricultural land or livestock manure production in rural areas, the resulting food produced is consumed within urban households. Dietary food consumption is the largest P input to, and output from, Twin Cities Metropolitan Area (TCMA), Minnesota, households. This 7-county area has a population of 2.9 million (2010), which is over half of the State's population. Human food accounts for 41% of the P input to and 46% of the P output from the TCMA; only about 1% of the P in food waste is recycled. Expanding on previous work by the Twin Cities Household Ecosystem Project (TCHEP), this P flow analysis aims to quantify nutrient inputs required throughout the agricultural system to produce the amount of food consumed by TCMA households, while examining P use efficiency by summarizing the extent of leakage (waste), storage, and reuse throughout these systems. Food corresponding to a minimum of 80% of the total dietary P-input for TCMA households can be produced entirely within Minnesota's agricultural system, hence our "food-shed" is more-or-less directly connected to urban consumers. The top food products which contribute the largest input of dietary P are milk, cheese, wheat flour, beef, chicken, caloric sweeteners and pork. Mapping out an agricultural footprint which can support this urban ecosystem enables P use to be conceptualized through a circular economy model, in this case with Minnesota as the food-shed boundary. Using state-level data, augmented with intensive interview data collected from local livestock and food production experts, a detailed P balance was developed for each major animal and

  14. Shedding light on Merlin's wizardry.

    PubMed

    Okada, Tomoyo; You, Liru; Giancotti, Filippo G

    2007-05-01

    Inactivation of the tumor suppressor Merlin, encoded by the NF2 (Neurofibromatosis type 2) gene, contributes to malignant conversion in many cell types. Merlin is an Ezrin-Radixin-Moesin protein and localizes underneath the plasma membrane at cell-cell junctions and other actin-rich sites. Recent studies indicate that Merlin mediates contact inhibition of proliferation by blocking recruitment of Rac to the plasma membrane. In mitogen-stimulated cells, p21-activated kinase phosphorylates Ser518 in the C-terminus of Merlin, inactivating the growth suppressive function of the protein. Furthermore, the myosin phosphatase MYPT1-PP1delta, has been identified as a direct activator of Merlin and its inhibition has been linked to malignant transformation. Finally, studies in the fruit fly Drosophila melanogaster have revealed that Merlin functions together with the band 4.1 protein Expanded to promote [corrected] the endocytosis of many signaling receptors, limiting [corrected] their accumulation at the plasma membrane, and to activate [corrected] the Hippo signaling pathway. Here, we review these recent findings and their relevance to the tumor suppressor function of Merlin. PMID:17442573

  15. Shedding Light, Reducing the Heat

    ERIC Educational Resources Information Center

    Perry, Mary

    2006-01-01

    Underlying the very heated debate over California's education budget for 2005-2006--and the battle over Proposition 76 on the November ballot--were two very different perspectives on school funding. These fundamental differences in perspective can stymie efforts to effect meaningful change. However, the Governor's Advisory Committee on Education…

  16. Shedding Light on Solar Power

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Glenn Research Center sponsored an SBIR contract with ENTECH, in which the company worked to mold its successful terrestrial concentrator technology into applications that would generate solar power for space missions. ENTECH's first application made use of small, dome-shaped Fresnel lenses to direct sunlight onto high- efficiency photovoltaic cells. After some key adjustments, the mini- dome lens array was flown as part of the U.S. Air Force/NASA Photovoltaic Array Space Power Plus Diagnostics (PASP Plus) flight experiment in 1994. Due to their three-dimensional shape, the mini- dome lenses entailed construction by a batch molding process, which is naturally more costly than a continuous process. To overcome this disadvantage and meet the requirement for precise solar pointing in two axes, ENTECH started developing solar concentrator arrays for space using a line-focus lens that can be mass-produced by a continuous process. This new technology, named Solar Concentrator Array with Refractive Linear Element Technology (SCARLET), was created with support from Glenn and the Ballistic Missile Defense Organization, and was used to power the NASA/Jet Propulsion Laboratory Deep Space 1 spacecraft.

  17. Shedding Light on Living Cells.

    PubMed

    Antognazza, Maria Rosa; Martino, Nicola; Ghezzi, Diego; Feyen, Paul; Colombo, Elisabetta; Endeman, Duco; Benfenati, Fabio; Lanzani, Guglielmo

    2015-12-01

    An overview of the optical methods available to modulate the cellular activity in cell cultures and biological tissues is presented, with a focus on the use of exogenous functional materials that absorb electromagnetic radiation and transduce it into a secondary stimulus for cell excitation, with high temporal and spatial resolution. Both organic and inorganic materials are critically evaluated, for in vitro and in vivo applications. Finally, as a direct practical application of optical-stimulation techniques, the most recent results in the realization of artificial visual implants are discussed. PMID:25469452

  18. Shedding Light on Shadow Education

    ERIC Educational Resources Information Center

    Kobakhidze, Magda Nutsa

    2015-01-01

    This essay review examines four different movies that directly or indirectly refer to the theme of private tutoring or, as it is widely called, shadow education. The movies, directed in locations as diverse as India, Turkey, and Cambodia, are all made from a critical perspective. The directors demonstrate challenges in public education systems and…

  19. Shedding Light on the Candela

    NASA Astrophysics Data System (ADS)

    Greene, Nathaniel R.

    2003-10-01

    Though the candela is one of the seven SI base units, it receives little attention from physics teachers. This paper will discuss the history of the candela, its measurement techniques (photometry), and its relation to the lumen. The luminous properties of incandescent and fluorescent lamps are compared. Of the SI base units, only the candela is linked to the peculiarities of human perception.

  20. [Shedding light on chaos theory].

    PubMed

    Chou, Shieu-Ming

    2004-06-01

    Gleick (1987) said that only three twentieth century scientific theories would be important enough to continue be of use in the twenty-first century: The Theory of Relativity, Quantum Theory, and Chaos Theory. Chaos Theory has become a craze which is being used to forge a new scientific system. It has also been extensively applied in a variety of professions. The purpose of this article is to introduce chaos theory and its nursing applications. Chaos is a sign of regular order. This is to say that chaos theory emphasizes the intrinsic potential for regular order within disordered phenomena. It is to be hoped that this article will inspire more nursing scientists to apply this concept to clinical, research, or administrative fields in our profession. PMID:15211774

  1. Shedding light on diphoton resonances

    NASA Astrophysics Data System (ADS)

    Craig, Nathaniel; Draper, Patrick; Kilic, Can; Thomas, Scott

    2016-06-01

    The experimental and theoretical implications of heavy digauge boson resonances that couple to, or are comprised of, new charged and strongly interacting matter are investigated. Observation and measurement of ratios of the resonant digauge boson channels W W , Z Z , γ γ , Z γ , and g g in the form of dijets provide a rather direct—and for some ratios a rather robust—probe of the gauge representations of the new matter. For a spin-zero resonance with the quantum numbers of the vacuum, the ratios of resonant W W and Z Z to γ γ channels, as well as the longitudinal vs transverse polarization fractions in the W W and Z Z channels, provide probes for possible mixing with the Higgs boson, while di-Higgs and ditop resonant channels, h h and t t , provide somewhat less sensitivity. We present a survey of possible underlying models for digauge boson resonances by considering various limits for the mass of the new charged and strongly interacting matter fields as well as the confinement scale of new hypergauge interactions under which they may also be charged. In these limits, resonances may be included as elementary weakly coupled spin-zero states or can correspond to hyperglueballs, hyperonia, or pseudoscalar hypermesons. For each of these cases, we make predictions for additional states that could be resonantly or pair produced and observed at the Large Hadron Collider or in future collider experiments. Heavy digauge boson resonances can provide a unified explanation for a number of small discrepancies and excesses in reported data from the Large Hadron Collider.

  2. Computational analysis of a tip vortex structure shed from a bio-inspired blade

    NASA Astrophysics Data System (ADS)

    Gomez, Sebastian; Gilkey, Lindsay N.; Kaiser, Bryan E.; Poroseva, Svetlana V.

    2013-11-01

    Understanding and predicting a tip vortex structure and its dynamics is of significant importance for all branches of aerodynamics. A particular focus of our research is the rotorcraft performance which is substantially influenced by a tip vortex. A tip vortex also is a major source of energy losses and acoustic noise. In the present study, an impact of a blade shape on a tip vortex structure is analyzed. Simulations are conducted of flows around a rectangular blade and a bio-inspired blade of the same area. An insect wing is chosen as a blade prototype. Indeed, insects developed physical characteristics that reduce energy consumption while permitting sustained and controlled flight at low level of noise. Analysis has been done to determine what insect poses flight characteristics closest to the small rotorcraft design goals. Commercial CFD software STAR-CCM + is used for conducting computations on structured and unstructured grids and for data post-processing. The authors acknowledge support from UNM CARC in a form of access to HPC and from CD-Adapco for providing Star-CCM+ for academic purposes. The first author's work was supported by the New Mexico Space Grant Consortium.

  3. Nanoparticle analysis sheds budding insights into genetic drivers of extracellular vesicle biogenesis

    PubMed Central

    Hurwitz, Stephanie N.; Conlon, Meghan M.; Rider, Mark A.; Brownstein, Naomi C.; Meckes, David G.

    2016-01-01

    Background Extracellular vesicles (EVs) are important mediators of cell-to-cell communication in healthy and pathological environments. Because EVs are present in a variety of biological fluids and contain molecular signatures of their cell or tissue of origin, they have great diagnostic and prognostic value. The ability of EVs to deliver biologically active proteins, RNAs and lipids to cells has generated interest in developing novel therapeutics. Despite their potential medical use, many of the mechanisms underlying EV biogenesis and secretion remain unknown. Methods Here, we characterized vesicle secretion across the NCI-60 panel of human cancer cells by nanoparticle tracking analysis. Using CellMiner, the quantity of EVs secreted by each cell line was compared to reference transcriptomics data to identify gene products associated with vesicle secretion. Results Gene products positively associated with the quantity of exosomal-sized vesicles included vesicular trafficking classes of proteins with Rab GTPase function and sphingolipid metabolism. Positive correlates of larger microvesicle-sized vesicle secretion included gene products involved in cytoskeletal dynamics and exocytosis, as well as Rab GTPase activation. One of the identified targets, CD63, was further evaluated for its role in vesicle secretion. Clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 knockout of the CD63 gene in HEK293 cells resulted in a decrease in small vesicle secretion, suggesting the importance of CD63 in exosome biogenesis. Conclusion These observations reveal new insights into genes involved in exosome and microvesicle formation, and may provide a means to distinguish EV sub-populations. This study offers a foundation for further exploration of targets involved in EV biogenesis and secretion. PMID:27421995

  4. Bayesian analysis of a morphological supermatrix sheds light on controversial fossil hominin relationships.

    PubMed

    Dembo, Mana; Matzke, Nicholas J; Mooers, Arne Ø; Collard, Mark

    2015-08-01

    The phylogenetic relationships of several hominin species remain controversial. Two methodological issues contribute to the uncertainty-use of partial, inconsistent datasets and reliance on phylogenetic methods that are ill-suited to testing competing hypotheses. Here, we report a study designed to overcome these issues. We first compiled a supermatrix of craniodental characters for all widely accepted hominin species. We then took advantage of recently developed Bayesian methods for building trees of serially sampled tips to test among hypotheses that have been put forward in three of the most important current debates in hominin phylogenetics--the relationship between Australopithecus sediba and Homo, the taxonomic status of the Dmanisi hominins, and the place of the so-called hobbit fossils from Flores, Indonesia, in the hominin tree. Based on our results, several published hypotheses can be statistically rejected. For example, the data do not support the claim that Dmanisi hominins and all other early Homo specimens represent a single species, nor that the hobbit fossils are the remains of small-bodied modern humans, one of whom had Down syndrome. More broadly, our study provides a new baseline dataset for future work on hominin phylogeny and illustrates the promise of Bayesian approaches for understanding hominin phylogenetic relationships. PMID:26202999

  5. Bayesian analysis of a morphological supermatrix sheds light on controversial fossil hominin relationships

    PubMed Central

    Dembo, Mana; Matzke, Nicholas J.; Mooers, Arne Ø.; Collard, Mark

    2015-01-01

    The phylogenetic relationships of several hominin species remain controversial. Two methodological issues contribute to the uncertainty—use of partial, inconsistent datasets and reliance on phylogenetic methods that are ill-suited to testing competing hypotheses. Here, we report a study designed to overcome these issues. We first compiled a supermatrix of craniodental characters for all widely accepted hominin species. We then took advantage of recently developed Bayesian methods for building trees of serially sampled tips to test among hypotheses that have been put forward in three of the most important current debates in hominin phylogenetics—the relationship between Australopithecus sediba and Homo, the taxonomic status of the Dmanisi hominins, and the place of the so-called hobbit fossils from Flores, Indonesia, in the hominin tree. Based on our results, several published hypotheses can be statistically rejected. For example, the data do not support the claim that Dmanisi hominins and all other early Homo specimens represent a single species, nor that the hobbit fossils are the remains of small-bodied modern humans, one of whom had Down syndrome. More broadly, our study provides a new baseline dataset for future work on hominin phylogeny and illustrates the promise of Bayesian approaches for understanding hominin phylogenetic relationships. PMID:26202999

  6. Shedding a Little (Sun)light on Data Analysis and Technology

    ERIC Educational Resources Information Center

    Winkel, Brian

    2012-01-01

    We present background and an activity meant to show both instructors and students that mere button pushing with technology is insufficient for success, but that additional thought and preparation will permit the technology to serve as an excellent tool in the understanding and learning of mathematics. (Contains 5 figures.)

  7. Analysis of Exoplanet Light Curves

    NASA Astrophysics Data System (ADS)

    Erdem, A.; Budding, E.; Rhodes, M. D.; Püsküllü, Ç.; Soydugan, F.; Soydugan, E.; Tüysüz, M.; Demircan, O.

    2015-07-01

    We have applied the close binary system analysis package WINFITTER to a variety of exoplanet transiting light curves taken both from the NASA Exoplanet Archive and our own ground-based observations. WINFitter has parameter options for a realistic physical model, including gravity brightening and structural parameters derived from Kopal's applications of the relevant Radau equation, and it includes appropriate tests for determinacy and adequacy of its best fitting parameter sets. We discuss a number of issues related to empirical checking of models for stellar limb darkening, surface maculation, Doppler beaming, microvariability, and transit time variation (TTV) effects. The Radau coefficients used in the light curve modeling, in principle, allow structural models of the component stars to be tested.

  8. A Crystallographic Study of the Role of Sequence Context in Thymine Glycol Bypass by a Replicative DNA Polymerase Serendipitously Sheds Light on the Exonuclease Complex

    SciTech Connect

    Aller, Pierre; Duclos, Stéphanie; Wallace, Susan S.; Doublié, Sylvie

    2012-06-27

    Thymine glycol (Tg) is the most common oxidation product of thymine and is known to be a strong block to replicative DNA polymerases. A previously solved structure of the bacteriophage RB69 DNA polymerase (RB69 gp43) in complex with Tg in the sequence context 5'-G-Tg-G shed light on how Tg blocks primer elongation: The protruding methyl group of the oxidized thymine displaces the adjacent 5'-G, which can no longer serve as a template for primer elongation [Aller, P., Rould, M. A., Hogg, M, Wallace, S. S. and Doublie S. (2007). A structural rationale for stalling of a replicative DNA polymerase at the most common oxidative thymine lesion, thymine glycol. Proc. Natl. Acad. Sci. USA, 104, 814-818.]. Several studies showed that in the sequence context 5'-C-Tg-purine, Tg is more likely to be bypassed by Klenow fragment, an A-family DNA polymerase. We set out to investigate the role of sequence context in Tg bypass in a B-family polymerase and to solve the crystal structures of the bacteriophage RB69 DNA polymerase in complex with Tg-containing DNA in the three remaining sequence contexts: 5'-A-Tg-G, 5'-T-Tg-G, and 5'-C-Tg-G. A combination of several factors - including the associated exonuclease activity, the nature of the 3' and 5' bases surrounding Tg, and the cis-trans interconversion of Tg - influences Tg bypass. We also visualized for the first time the structure of a well-ordered exonuclease complex, allowing us to identify and confirm the role of key residues (Phe123, Met256, and Tyr257) in strand separation and in the stabilization of the primer strand in the exonuclease site.

  9. 23. CONTEXTUAL, RAIL CARS IN MU SHED Delaware, Lackawanna ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. CONTEXTUAL, RAIL CARS IN MU SHED - Delaware, Lackawanna & Western Railroad Freight & Rail Yard, Multiple Unit Light Inspection Shed, New Jersey Transit Hoboken Terminal Rail Yard, Hoboken, Hudson County, NJ

  10. 7. Fog signal house and shed, view south, north and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Fog signal house and shed, view south, north and west sides of fog signal house, northeast and northwest sides of shed - Whitehead Light Station, Whitehead Island, East northeast of Tenants Harbor, Spruce Head, Knox County, ME

  11. Expression and immunoaffinity purification of recombinant soluble human GPR56 protein for the analysis of GPR56 receptor shedding by ELISA.

    PubMed

    Yang, Tai-Yun; Chiang, Nien-Yi; Tseng, Wen-Yi; Pan, Hsiao-Lin; Peng, Yen-Ming; Shen, Jiann-Jong; Wu, Kuo-An; Kuo, Ming-Ling; Chang, Gin-Wen; Lin, Hsi-Hsien

    2015-05-01

    GPR56 is a multi-functional adhesion-class G protein-coupled receptor involved in biological systems as diverse as brain development, male gonad development, myoblast fusion, hematopoietic stem cell maintenance, tumor growth and metastasis, and immune-regulation. Ectodomain shedding of human GPR56 receptor has been demonstrated previously, however the quantitative detection of GPR56 receptor shedding has not been investigated fully due to the lack of appropriate assays. Herein, an efficient system of expression and immune-affinity purification of the recombinant soluble extracellular domain of human GPR56 (sGPR56) protein from a stably transduced human melanoma cell line was established. The identity and functionality of the recombinant human sGPR56 protein were verified by Western blotting and mass spectrometry, and ligand-binding assays, respectively. Combined with the use of two recently generated anti-GPR56 monoclonal antibodies, a sensitive sandwich ELISA assay was successfully developed for the quantitative detection of human sGPR56 molecule. We found that GPR56 receptor shedding occurred constitutively and was further increased in activated human melanoma cells expressing endogenous GPR56. In conclusion, we report herein an efficient system for the production and purification of human sGPR56 protein for the establishment of a quantitative ELISA analysis of GPR56 receptor shedding. PMID:25437104

  12. Per-Pixel Lighting Data Analysis

    SciTech Connect

    Inanici, Mehlika

    2005-08-01

    This report presents a framework for per-pixel analysis of the qualitative and quantitative aspects of luminous environments. Recognizing the need for better lighting analysis capabilities and appreciating the new measurement abilities developed within the LBNL Lighting Measurement and Simulation Toolbox, ''Per-pixel Lighting Data Analysis'' project demonstrates several techniques for analyzing luminance distribution patterns, luminance ratios, adaptation luminance and glare assessment. The techniques are the syntheses of the current practices in lighting design and the unique practices that can be done with per-pixel data availability. Demonstrated analysis techniques are applicable to both computer-generated and digitally captured images (physically-based renderings and High Dynamic Range photographs).

  13. A GRB tool shed

    NASA Astrophysics Data System (ADS)

    Haglin, David J.; Roiger, Richard J.; Hakkila, Jon; Pendleton, Geoffrey; Mallozzi, Robert

    2000-09-01

    We describe the design of a suite of software tools to allow users to query Gamma Ray Burst (GRB) data and perform data mining expeditions. We call this suite of tools a shed (SHell for Expeditions using Datamining). Our schedule is to have a completed prototype (funded via the NASA AISRP) by February, 2002. Meanwhile, interested users will find a partially functioning tool shed at http:/grb.mankato.msus.edu. .

  14. Delineating resource sheds in aquatic ecosystems (presentation)

    EPA Science Inventory

    Analysis of spatially-explicit ecological phenomena in aquatic ecosystems is impeded by a lack of knowledge of, and tools to delimit, spatial patterns of material supply to point locations. Here we apply the concept of "resource sheds" to coasts and watersheds. Resource sheds ar...

  15. Rainfall simulation experiments and Water Drop Penetration Time measurements shed light on the impact of water repellency on soils under organic farming management in Eastern Spain

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; González, Óscar; León, Javier; Jordán, Antonio

    2015-04-01

    Water repellency is a well-know soil property since the research of professor Stefan Helmut Doerr recovered and powered the research developed by professor DeBano (Atanassova and Doerr, 2011; ; Jordán et al., 2011; Bodí et al., 2012; González Peñaloza et al., 2012 Bodí et al., 2013; García Moreno et al., 2013; Jordán et al., 2013; Badía-Villas et al., 2014; Jordán et al., 2013; Jiménez Morillo et al., 2015). However, little is known about the impact of water repellency in surface runoff generation, although usually is accepted that when more soil water repellent is a soil, higher will be the surface runoff discharge (Stoff et al., 2011; Madsen et al., 2011; León et al., 2013; Lozano et al., 2013; Mataix-Solera et al., 2013; Santos et al., 2015). And the impact of the water repellency and then the higher surface wash discharge can trigger high erosion rates (Kröpfl et al., 2013; Mandal and Sharda 2013; Zhao et al., 2013). However these relationships were not demonstrated as the most water repellent soils are the one with high organic contents, and those soils do not have soil losses, probably due to the high infiltration rates due to the macropore flow. Rainfall simulation experiments can shed light in the runoff generation mechanism as they can control the rainfall intensity (Bodí et al., 2012; Iserloh et al., 2012; Iserloh et al., 2013), and inform about the main mechanism of the soil erosion process Cerdà and Jurgensen, 2011; Daugherty et al., 2011; Podwojewski et al., 2011; Dunkerley, 2012; Garel et al., 2012; Jouquet et al., 2012; Kibet et al., 2013; Butzen et al., 2014; Ma et al., 2014; Martínez Murillo et al., 2013). To determine the relationship between surface runoff generated under simulated rainfall (Cerdà, 1988a; 1988b; Cerdà et al., 1998; Ziadat and Taimeh, 2013) with a small rainfall simulator (0.25 m2) and water repellency measurements with the Water Drop Penetration time methods were done (Bodí et al., 2012). The results show that

  16. Rainfall simulation experiments and Water Drop Penetration Time measurements shed light on the impact of water repellency on soils under organic farming management in Eastern Spain

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; González, Óscar; León, Javier; Jordán, Antonio

    2015-04-01

    Water repellency is a well-know soil property since the research of professor Stefan Helmut Doerr recovered and powered the research developed by professor DeBano (Atanassova and Doerr, 2011; ; Jordán et al., 2011; Bodí et al., 2012; González Peñaloza et al., 2012 Bodí et al., 2013; García Moreno et al., 2013; Jordán et al., 2013; Badía-Villas et al., 2014; Jordán et al., 2013; Jiménez Morillo et al., 2015). However, little is known about the impact of water repellency in surface runoff generation, although usually is accepted that when more soil water repellent is a soil, higher will be the surface runoff discharge (Stoff et al., 2011; Madsen et al., 2011; León et al., 2013; Lozano et al., 2013; Mataix-Solera et al., 2013; Santos et al., 2015). And the impact of the water repellency and then the higher surface wash discharge can trigger high erosion rates (Kröpfl et al., 2013; Mandal and Sharda 2013; Zhao et al., 2013). However these relationships were not demonstrated as the most water repellent soils are the one with high organic contents, and those soils do not have soil losses, probably due to the high infiltration rates due to the macropore flow. Rainfall simulation experiments can shed light in the runoff generation mechanism as they can control the rainfall intensity (Bodí et al., 2012; Iserloh et al., 2012; Iserloh et al., 2013), and inform about the main mechanism of the soil erosion process Cerdà and Jurgensen, 2011; Daugherty et al., 2011; Podwojewski et al., 2011; Dunkerley, 2012; Garel et al., 2012; Jouquet et al., 2012; Kibet et al., 2013; Butzen et al., 2014; Ma et al., 2014; Martínez Murillo et al., 2013). To determine the relationship between surface runoff generated under simulated rainfall (Cerdà, 1988a; 1988b; Cerdà et al., 1998; Ziadat and Taimeh, 2013) with a small rainfall simulator (0.25 m2) and water repellency measurements with the Water Drop Penetration time methods were done (Bodí et al., 2012). The results show that

  17. 13. Relationship of east tool shed, west tool shed, residence, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Relationship of east tool shed, west tool shed, residence, claim house, and privy to each other and immediate surroundings, looking north - George Spangerberger Farmstead, 2012 West Illinois Avenue, South Hutchinson, Reno County, KS

  18. 12. Relationship of est tool shed, west tool shed, residence, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Relationship of est tool shed, west tool shed, residence, claim house, and chicken house to each other and immediate surroundings, looking southeast - George Spangerberger Farmstead, 2012 West Illinois Avenue, South Hutchinson, Reno County, KS

  19. 11. Relationship of barn, east tool shed, west tool shed, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Relationship of barn, east tool shed, west tool shed, and residence to overall farmstead site, looking southeast - George Spangerberger Farmstead, 2012 West Illinois Avenue, South Hutchinson, Reno County, KS

  20. A Shoot-Specific Hypoxic Response of Arabidopsis Sheds Light on the Role of the Phosphate-Responsive Transcription Factor PHOSPHATE STARVATION RESPONSE11[W

    PubMed Central

    Klecker, Maria; Gasch, Philipp; Peisker, Helga; Dörmann, Peter; Schlicke, Hagen; Grimm, Bernhard; Mustroph, Angelika

    2014-01-01

    Plant responses to biotic and abiotic stresses are often very specific, but signal transduction pathways can partially or completely overlap. Here, we demonstrate that in Arabidopsis (Arabidopsis thaliana), the transcriptional responses to phosphate starvation and oxygen deficiency stress comprise a set of commonly induced genes. While the phosphate deficiency response is systemic, under oxygen deficiency, most of the commonly induced genes are found only in illuminated shoots. This jointly induced response to the two stresses is under control of the transcription factor PHOSPHATE STARVATION RESPONSE1 (PHR1), but not of the oxygen-sensing N-end rule pathway, and includes genes encoding proteins for the synthesis of galactolipids, which replace phospholipids in plant membranes under phosphate starvation. Despite the induction of galactolipid synthesis genes, total galactolipid content and plant survival are not severely affected by the up-regulation of galactolipid gene expression in illuminated leaves during hypoxia. However, changes in galactolipid molecular species composition point to an adaptation of lipid fluxes through the endoplasmic reticulum and chloroplast pathways during hypoxia. PHR1-mediated signaling of phosphate deprivation was also light dependent. Because a photoreceptor-mediated PHR1 activation was not detectable under hypoxia, our data suggest that a chloroplast-derived retrograde signal, potentially arising from metabolic changes, regulates PHR1 activity under both oxygen and phosphate deficiency. PMID:24753539

  1. A gene-based map of the Nod factor-independent Aeschynomene evenia sheds new light on the evolution of nodulation and legume genomes.

    PubMed

    Chaintreuil, Clémence; Rivallan, Ronan; Bertioli, David J; Klopp, Christophe; Gouzy, Jérôme; Courtois, Brigitte; Leleux, Philippe; Martin, Guillaume; Rami, Jean-François; Gully, Djamel; Parrinello, Hugues; Séverac, Dany; Patrel, Delphine; Fardoux, Joël; Ribière, William; Boursot, Marc; Cartieaux, Fabienne; Czernic, Pierre; Ratet, Pascal; Mournet, Pierre; Giraud, Eric; Arrighi, Jean-François

    2016-08-01

    Aeschynomene evenia has emerged as a new model legume for the deciphering of the molecular mechanisms of an alternative symbiotic process that is independent of the Nod factors. Whereas most of the research on nitrogen-fixing symbiosis, legume genetics and genomics has so far focused on Galegoid and Phaseolid legumes, A. evenia falls in the more basal and understudied Dalbergioid clade along with peanut (Arachis hypogaea). To provide insights into the symbiotic genes content and the structure of the A. evenia genome, we established a gene-based genetic map for this species. Firstly, an RNAseq analysis was performed on the two parental lines selected to generate a F2 mapping population. The transcriptomic data were used to develop molecular markers and they allowed the identification of most symbiotic genes. The resulting map comprised 364 markers arranged in 10 linkage groups (2n = 20). A comparative analysis with the sequenced genomes of Arachis duranensis and A. ipaensis, the diploid ancestors of peanut, indicated blocks of conserved macrosynteny. Altogether, these results provided important clues regarding the evolution of symbiotic genes in a Nod factor-independent context. They provide a basis for a genome sequencing project and pave the way for forward genetic analysis of symbiosis in A. evenia. PMID:27298380

  2. A gene-based map of the Nod factor-independent Aeschynomene evenia sheds new light on the evolution of nodulation and legume genomes

    PubMed Central

    Chaintreuil, Clémence; Rivallan, Ronan; Bertioli, David J.; Klopp, Christophe; Gouzy, Jérôme; Courtois, Brigitte; Leleux, Philippe; Martin, Guillaume; Rami, Jean-François; Gully, Djamel; Parrinello, Hugues; Séverac, Dany; Patrel, Delphine; Fardoux, Joël; Ribière, William; Boursot, Marc; Cartieaux, Fabienne; Czernic, Pierre; Ratet, Pascal; Mournet, Pierre; Giraud, Eric; Arrighi, Jean-François

    2016-01-01

    Aeschynomene evenia has emerged as a new model legume for the deciphering of the molecular mechanisms of an alternative symbiotic process that is independent of the Nod factors. Whereas most of the research on nitrogen-fixing symbiosis, legume genetics and genomics has so far focused on Galegoid and Phaseolid legumes, A. evenia falls in the more basal and understudied Dalbergioid clade along with peanut (Arachis hypogaea). To provide insights into the symbiotic genes content and the structure of the A. evenia genome, we established a gene-based genetic map for this species. Firstly, an RNAseq analysis was performed on the two parental lines selected to generate a F2 mapping population. The transcriptomic data were used to develop molecular markers and they allowed the identification of most symbiotic genes. The resulting map comprised 364 markers arranged in 10 linkage groups (2n = 20). A comparative analysis with the sequenced genomes of Arachis duranensis and A. ipaensis, the diploid ancestors of peanut, indicated blocks of conserved macrosynteny. Altogether, these results provided important clues regarding the evolution of symbiotic genes in a Nod factor-independent context. They provide a basis for a genome sequencing project and pave the way for forward genetic analysis of symbiosis in A. evenia. PMID:27298380

  3. 15. GENERAL VIEW OF NORTHWEST SIDE OF SHED, WITH AN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. GENERAL VIEW OF NORTHWEST SIDE OF SHED, WITH AN OBLIQUE VIEW OF THE STEP-DOWN ROOF AND TWO BANKS OF CLEARSTORY LIGHTS - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  4. Peranso - Light curve and period analysis software

    NASA Astrophysics Data System (ADS)

    Paunzen, E.; Vanmunster, T.

    2016-03-01

    A time series is a sample of observations of well-defined data points obtained through repeated measurements over a certain time range. The analysis of such data samples has become increasingly important not only in natural science but also in many other fields of research. Peranso offers a complete set of powerful light curve and period analysis functions to work with large astronomical data sets. Substantial attention has been given to ease-of-use and data accuracy, making it one of the most productive time series analysis software available. In this paper, we give an introduction to Peranso and its functionality.

  5. Shedding new light on kaon-nucleon/nuclei interaction and its astrophysical implications with the AMADEUS experiment at DAΦNE

    NASA Astrophysics Data System (ADS)

    Scordo, A.; Bazzi, M.; Bellotti, G.; Berucci, C.; Bosnar, D.; Bragadireanu, A. M.; Clozza, A.; Cargnelli, M.; Curceanu, C.; Butt, A. Dawood; Grande, R. Del; Fabbietti, L.; Fiorini, C.; Ghio, F.; Guaraldo, C.; Iliescu, M.; Sandri, P. Levi; Marton, J.; Pietreanu, D.; Piscicchia, K.; Shi, H.; Sirghi, D.; Sirghi, F.; Tucakovic, I.; Doce, O. Vazquez; Wiedmann, W.; Zmeskal, J.

    2016-05-01

    The AMADEUS experiment deals with the investigation of the low-energy kaon-nuclei hadronic interaction at the DAΦNE collider at LNF-INFN. The aim is to answer fundamental longstanding questions in the non-perturbative QCD strangeness sector. The antikaon-nucleon potential is investigated searching for signals from possible bound kaonic clusters, which would open the possibility for the formation of cold dense baryonic matter. The confirmation of this scenario may imply a fundamental role of strangeness in astrophysics. AMADEUS step 0 consisted in the reanalysis of 2004/2005 KLOE dataset, exploiting K- absorptions in H, 4He, 9Be and 12C in the setup materials. In this paper, together with a review on the multi-nucleon K- absorption and the particle identification procedure, the first results on the Σ0p channel will be presented including a statistical analysis on the possible accomodation of a deeply bound state.

  6. A detection of Milankovitch frequencies in tephra records of arc volcanism: Shedding light on a feedback loop between climate and volcanism. (Invited)

    NASA Astrophysics Data System (ADS)

    Kutterolf, S.; Jegen, M.; Schindlbeck, J. C.; Mitrovica, J. X.; Kwasnitschka, T.; Freundt, A.; Huybers, P. J.

    2013-12-01

    Although it is well understood that volcanism can impact global climate or tectonics can influence volcanism, it is less well appreciated that climate can influence volcanism. In this regard, both regional and global studies have provided compelling evidence that ice age loading processes modulate the frequency of volcanic eruption. However, a rigorous detection of Milankovitch periodicities in global volcanic output across the Pleistocene-Holocene ice age, which would firmly establish a connection between ice age climate and eruption frequency, has remained elusive. To this end, we report on a spectral analysis of a large number of well-preserved ash plume deposits recorded in marine sediments along the Pacific Ring of Fire, which accounts for about half of the global length of 44,000 km of active subduction. Eruptions at arc volcanoes tend to be highly explosive. We analyze the Pleistocene-to-Recent marine records of widespread tephras of sub-Plinian to Plinian, and occasionally co-ignimbrite, origin since they provide a well-preserved record of how eruption frequencies varied with depth (and, hence time). Our analysis yields a statistically significant detection of spectral peaks at the obliquity period. We propose that the variability in volcanic activity results from crustal stress changes associated with ice age mass redistribution. In particular, increased volcanism lags behind the highest rate of increasing eustatic sea level (decreasing global ice volume) by 4.0 × 3.6 kyr and correlates well with numerical predictions of stress changes at volcanically active sites. Our results strongly support the presence of a coupling between ice age climate, volcanism and the continental stress field. In future work we will incorporate longer tephra time series and more accurate age controls in order to improve - and widen - our detection of Milankovitch periodicities thus further elucidating the feedback loop between climate and volcanism as well as tectonics.

  7. Combination of transient 2D-IR experiments and ab initio computations sheds light on the formation of the charge-transfer state in photoexcited carbonyl carotenoids.

    PubMed

    Di Donato, Mariangela; Segado Centellas, Mireia; Lapini, Andrea; Lima, Manuela; Avila, Francisco; Santoro, Fabrizio; Cappelli, Chiara; Righini, Roberto

    2014-08-14

    The excited state dynamics of carbonyl carotenoids is very complex because of the coupling of single- and doubly excited states and the possible involvement of intramolecular charge-transfer (ICT) states. In this contribution we employ ultrafast infrared spectroscopy and theoretical computations to investigate the relaxation dynamics of trans-8'-apo-β-carotenal occurring on the picosecond time scale, after excitation in the S2 state. In a (slightly) polar solvent like chloroform, one-dimensional (T1D-IR) and two-dimensional (T2D-IR) transient infrared spectroscopy reveal spectral components with characteristic frequencies and lifetimes that are not observed in nonpolar solvents (cyclohexane). Combining experimental evidence with an analysis of CASPT2//CASSCF ground and excited state minima and energy profiles, complemented with TDDFT calculations in gas phase and in solvent, we propose a photochemical decay mechanism for this system where only the bright single-excited 1Bu(+) and the dark double-excited 2Ag(-) states are involved. Specifically, the initially populated 1Bu(+) relaxes toward 2Ag(-) in 200 fs. In a nonpolar solvent 2Ag(-) decays to the ground state (GS) in 25 ps. In polar solvents, distortions along twisting modes of the chain promote a repopulation of the 1Bu(+) state which then quickly relaxes to the GS (18 ps in chloroform). The 1Bu(+) state has a high electric dipole and is the main contributor to the charge-transfer state involved in the dynamics in polar solvents. The 2Ag(-) → 1Bu(+) population transfer is evidenced by a cross peak on the T2D-IR map revealing that the motions along the same stretching of the conjugated chain on the 2Ag(-) and 1Bu(+) states are coupled. PMID:25050938

  8. Arthroaspis n. gen., a common element of the Sirius Passet Lagerstätte (Cambrian, North Greenland), sheds light on trilobite ancestry

    PubMed Central

    2013-01-01

    Background Exceptionally preserved Palaeozoic faunas have yielded a plethora of trilobite-like arthropods, often referred to as lamellipedians. Among these, Artiopoda is supposed to contain taxa united by a distinctive appendage structure. This includes several well supported groups, Helmetiida, Nektaspida, and Trilobita, as well as a number of problematic taxa. Interrelationships remain unclear, and the position of the lamellipedian arthropods as a whole also remains the subject of debate. Results Arthroaspis bergstroemi n. gen. n. sp., a new arthropod from the early Cambrian Sirius Passet Lagerstätte of North Greenland shows a striking combination of both dorsal and ventral characters of Helmetiida, Nektaspida, and Trilobita. Cladistic analysis with a broad taxon sampling of predominantly early Palaeozoic arthropods yields a monophyletic Lamellipedia as sister taxon to the Crustacea or Tetraconata. Artiopoda is resolved as paraphyletic, giving rise to the Marrellomorpha. Within Lamellipedia, a clade of pygidium bearing taxa is resolved that can be shown to have a broadly helmetiid-like tergite morphology in its ground pattern. This morphology is plesiomorphically retained in Helmetiida and in Arthroaspis, which falls basally into a clade containing Trilobita. The trilobite appendages, though similar to those of other lamellipedians in gross morphology, have a unique outward rotation of the anterior trunk appendages, resulting in a ‘hard wired’ lateral splay, different to that observed in other Lamellipedia. Conclusions The combination of helmetiid, trilobite, and nektaspid characters in Arthroaspis gives important hints concerning character polarisation within the trilobite-like arthropods. The distinctive tergite morphology of trilobites, with its sophisticated articulating devices, is derived from flanged edge-to-edge articulating tergites forming a shield similar to the helmetiids, previously considered autapomorphic for that group. The stereotypical

  9. Synchrotron-Based Techniques Shed Light on Mechanisms of Plant Sensitivity and Tolerance to High Manganese in the Root Environment1[OPEN

    PubMed Central

    Blamey, F. Pax C.; Hernandez-Soriano, Maria C.; Cheng, Miaomiao; Tang, Caixian; Paterson, David J.; Lombi, Enzo; Wang, Wei Hong; Scheckel, Kirk G.; Kopittke, Peter M.

    2015-01-01

    Plant species differ in response to high available manganese (Mn), but the mechanisms of sensitivity and tolerance are poorly understood. In solution culture, greater than or equal to 30 µm Mn decreased the growth of soybean (Glycine max), but white lupin (Lupinus albus), narrow-leafed lupin (Lupin angustifolius), and sunflower (Helianthus annuus) grew well at 100 µm Mn. Differences in species’ tolerance to high Mn could not be explained simply by differences in root, stem, or leaf Mn status, being 8.6, 17.1, 6.8, and 9.5 mmol kg–1 leaf fresh mass at 100 µm Mn. Furthermore, x-ray absorption near edge structure analyses identified the predominance of Mn(II), bound mostly to malate or citrate, in roots and stems of all four species. Rather, differences in tolerance were due to variations in Mn distribution and speciation within leaves. In Mn-sensitive soybean, in situ analysis of fresh leaves using x-ray fluorescence microscopy combined with x-ray absorption near edge structure showed high Mn in the veins, and manganite [Mn(III)] accumulated in necrotic lesions apparently through low Mn sequestration in vacuoles or other vesicles. In the two lupin species, most Mn accumulated in vacuoles as either soluble Mn(II) malate or citrate. In sunflower, Mn was sequestered as manganite at the base of nonglandular trichomes. Hence, tolerance to high Mn was ascribed to effective sinks for Mn in leaves, as Mn(II) within vacuoles or through oxidation of Mn(II) to Mn(III) in trichomes. These two mechanisms prevented Mn accumulation in the cytoplasm and apoplast, thereby ensuring tolerance to high Mn in the root environment. PMID:26395840

  10. Analysis of light curve of LP Camelopardalis

    NASA Astrophysics Data System (ADS)

    Prudil, Z.; Skarka, M.; Zejda, M.

    2016-05-01

    We present photometric analysis of the RRab type pulsating star LP Cam. The star was observed at Brno Observatory and Planetarium during nine nights. Measurements were calibrated to the Johnson photometric system. Four captured and thirteen previously published maxima timings allowed us to refine the pulsation period and the zero epoch. The light curve was Fourier decomposed to estimate physical parameters using empirical relations. Our results suggest that LP Cam is a common RR Lyrae star with high, almost solar metallicity.

  11. 29. View of oil storage shed, looking northeast. Photo by ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. View of oil storage shed, looking northeast. Photo by Brian C. Morris, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  12. 7. Outhouse and shed, view west northwest, south and east ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Outhouse and shed, view west northwest, south and east sides - Ram Island Light Station, Ram Island, south of Ocean Point & just north of Fisherman Island, marking south side of Fisherman Island Passage, Ocean Point, Lincoln County, ME

  13. 25. View of storage shed and motor house for tramway, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. View of storage shed and motor house for tramway, looking southwest. Photo by Brian C. Morris, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  14. 7. Shed and keeper' house with helicopter pad in foreground, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Shed and keeper' house with helicopter pad in foreground, view east, southwest and northwest sides - Goat Island Light Station, Goat Island, next to entrance to Cape Porpoise Harbor, just south of Trott Island, Cape Porpoise, York County, ME

  15. 1. View west, east sides of shed, lighthouse, keeper's house ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View west, east sides of shed, lighthouse, keeper's house and boat house - Squirrel Point Light Station, Off Highway 127, Steen Road to end of Bald Head Road, .8 mile down footpath, Arrowsic, Sagadahoc County, ME

  16. 7. View southwest, east and north sides of shed and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. View southwest, east and north sides of shed and keeper's house - Squirrel Point Light Station, Off Highway 127, Steen Road to end of Bald Head Road, .8 mile down footpath, Arrowsic, Sagadahoc County, ME

  17. A phylogenetic analysis of the British flora sheds light on the evolutionary and ecological factors driving plant invasions

    PubMed Central

    Lim, Junying; Crawley, Mick J; De Vere, Natasha; Rich, Tim; Savolainen, Vincent

    2014-01-01

    Darwin's naturalization hypothesis predicts that invasive species should perform better in their novel range in the absence of close relatives in the native flora due to reduced competition. Evidence from recent taxonomic and phylogenetic-based studies, however, is equivocal. We test Darwin's naturalization hypothesis at two different spatial scales using a fossil-dated molecular phylogenetic tree of the British native and alien flora (ca. 1600 species) and extensive, fine-scale survey data from the 1998 Countryside Survey. At both landscape and local scales, invasive species were neither significantly more nor less related to the native flora than their non-invasive alien counterparts. Species invasiveness was instead correlated with higher nitrogen and moisture preference, but not other life history traits such as life-form and height. We argue that invasive species spread in Britain is hence more likely determined by changes in land use and other anthropogenic factors, rather than evolutionary history. Synthesis. The transition from non-invasive to invasive is not related to phylogenetic distinctiveness to the native community, but instead to their environmental preferences. Therefore, combating biological invasions in the Britain and other industrialized countries need entirely different strategies than in more natural environments. PMID:25540688

  18. New Instruments Shed Light On Astronomy's Future.

    PubMed

    Travis, J

    1994-04-15

    KONA, HAWAII-The snowy 14,000-foot summit of Mauna Kea, with its bevy of powerful telescopes including the just-completed Keck, provided an appropriate backdrop for a recent ocean-side gathering of astronomers and engineers to discuss "Astronomical Telescopes and Instrumentation for the 21st Century." Last month's meeting was organized by the Society of Photo-Optical Instrumentation Engineers, and included a status report on liquid mirror telescopes, discussion of a space observatory that may make optical and x-ray astronomers best friends, and a modest proposal to cover the globe with a network of small, automated telescopes. PMID:17836897

  19. Shedding new light on gas dynamics

    NASA Technical Reports Server (NTRS)

    Mckenzie, Robert L.; Hanson, Ronald K.; Eckbreth, Alan C.

    1992-01-01

    Modern laser-spectroscopic techniques usually incorporate one or more laser beams and depend on their radiative interaction with some spectroscopic feature of the gas. Attention is given to laser absorption, laser-induced fluorescence, Rayleigh scattering, and Raman scattering. Consideration is given to UV Rayleigh scattering applied to aerodynamic flows to obtain images of a supersonic boundary layer that show instantaneous turbulent structures at a level of detail not achieved by any other practical method.

  20. Black Holes Shed Light on Galaxy Formation

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This videotape is comprised of several segments of animations on black holes and galaxy formation, and several segments of an interview with Dr. John Kormendy. The animation segments are: (1) a super massive black hole, (2) Centarus A active black hole found in a collision, (3) galaxy NGC-4261 (active black hole and jet model), (4) galaxy M-32 (orbits of stars are effected by the gravity of the black hole), (5) galaxy M-37 (motion of stars increases as mass of black hole increases), (6) Birth of active galactic nuclei, (7) the collision of two galaxy leads to merger of the black holes, (8) Centarus A and simulation of the collision of 2 galaxies. There are also several segments of an interview with John Kormendy. In these segments he discusses the two most important aspects of his recent black hole work: (1) the correlations between galaxies speed and the mass of the black holes, and (2) the existence of black holes and galactic formation. He also discusses the importance of the Hubble Space Telescope and the Space Telescope Imaging Spectrograph to the study of black holes. He also shows the methodology of processing images from the spectrograph in his office.

  1. Pyrosequencing sheds light on DNA sequencing.

    PubMed

    Ronaghi, M

    2001-01-01

    DNA sequencing is one of the most important platforms for the study of biological systems today. Sequence determination is most commonly performed using dideoxy chain termination technology. Recently, pyrosequencing has emerged as a new sequencing methodology. This technique is a widely applicable, alternative technology for the detailed characterization of nucleic acids. Pyrosequencing has the potential advantages of accuracy, flexibility, parallel processing, and can be easily automated. Furthermore, the technique dispenses with the need for labeled primers, labeled nucleotides, and gel-electrophoresis. This article considers key features regarding different aspects of pyrosequencing technology, including the general principles, enzyme properties, sequencing modes, instrumentation, and potential applications. PMID:11156611

  2. Clinical Trials Shed Light on Minority Health

    MedlinePlus

    ... determine whether FDA approves a manufacturer’s application for marketing approval. "Potential racial, ethnic and other differences in ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  3. New light shed on the oldest insect.

    PubMed

    Engel, Michael S; Grimaldi, David A

    2004-02-12

    Insects are the most diverse lineage of all life in numbers of species, and ecologically they dominate terrestrial ecosystems. However, how and when this immense radiation of animals originated is unclear. Only a few fossils provide insight into the earliest stages of insect evolution, and among them are specimens in chert from Rhynie, Scotland's Old Red Sandstone (Pragian; about 396-407 million years ago), which is only slightly younger than formations harbouring the earliest terrestrial faunas. The most well-known animal from Rhynie is the springtail Rhyniella praecursor (Entognatha; Collembola), long considered to be the oldest hexapod. For true insects (Ectognatha), the oldest records are two apparent wingless insects from later in the Devonian period of North America. Here we show, however, that a fragmentary fossil from Rhynie, Rhyniognatha hirsti, is not only the earliest true insect but may be relatively derived within basal Ectognatha. In fact, Rhyniognatha has derived characters shared with winged insects, suggesting that the origin of wings may have been earlier than previously believed. Regardless, Rhyniognatha indicates that insects originated in the Silurian period and were members of some of the earliest terrestrial faunas. PMID:14961119

  4. Shedding light on physician performance transparency.

    PubMed

    Norris, David

    2016-02-01

    Healthcare providers can use performance data already being collected to: Manage risk more proactively by identifying high-risk, high-cost areas. Make call centers more effective and websites work better, thereby improving the patient experience. Embrace the trend toward consumerism by enabling patients with performance data. Modify behavior and make systemic improvements where weaknesses are identified. Improve the level of care by better matching patients and providers. Regain public trust and confidence by sharing real data as an alternative to subjective commentary on physician performance. PMID:26999978

  5. Shedding light on baryonic dark matter

    NASA Technical Reports Server (NTRS)

    Silk, Joseph

    1991-01-01

    Halo dark matter, if it is baryonic, may plausibly consist of compact stellar remnants. Jeans mass clouds containing 10 to the 6th to 10 to the 8th solar masses could have efficiently formed stars in the early universe and could plausibly have generated, for a suitably top-heavy stellar initial mass function, a high abundance of neutron stars as well as a small admixture of long-lived low mass stars. Within the resulting clusters of dark remnants, which eventually are tidally disrupted when halos eventually form, captures of neutron stars by nondegenerate stars resulted in formation of close binaries. These evolve to produce, by the present epoch, an observable X-ray signal associated with dark matter aggregations in galaxy cluster cores.

  6. Ethics Workshop Sheds Light on Gray Areas

    NASA Astrophysics Data System (ADS)

    Townsend, Randy; Williams, Billy

    2014-02-01

    AGU's Scientific Integrity and Professional Ethics Workshop at the 2013 Fall Meeting, held on 9 December, highlighted the courageous conversations necessary to navigate through questions of scientific integrity and professional ethics. Participants debated real-world scenarios surrounding authorship, data management, plagiarism, and conflicts of interest. These discussions emphasized the importance of preserving scientific integrity and the responsibility of each member to uphold the standards of scientific conduct.

  7. Endothelial Glycocalyx: Shedding Light on Malaria Pathogenesis.

    PubMed

    Hempel, Casper; Pasini, Erica M; Kurtzhals, Jørgen A L

    2016-06-01

    Malaria is estimated to kill 438 000 people annually, mostly due to severe malaria, which is closely associated with microcirculatory vasculopathy, although its pathogenesis remains incompletely understood. Here, we propose that the largely ignored glycocalyx of the vascular endothelium plays an important role in facilitating the pathogenesis of severe malaria. PMID:27161599

  8. Shedding a new light on hazardous waste

    SciTech Connect

    Reece, N.

    1991-02-01

    The sun's ability to detoxify waterborne chemicals has long been known; polluted streams, for example, become cleaner as they flow through sunlit areas. Solar detoxification harnesses this natural degradation process for beneficial ends, producing simple, nonhazardous substances from hazardous organic chemicals. Solar detoxification systems now being developed break down these chemicals without using the fossil fuels required by conventional technologies. Sunlight destroys hazardous waste because of the distinctive properties of photons, the packets of energy that make up sunlight. Low-energy photons add thermal energy that will heat toxic chemicals; high-energy photons add the energy needed to break the chemical bonds of these chemicals. The detoxification process discussed here takes advantage of this latter group of photons found in the ultraviolet portion of the solar spectrum. 4 figs.

  9. Shedding light on insight: Priming bright ideas

    PubMed Central

    Slepian, Michael L.; Weisbuch, Max; Rutchick, Abraham M.; Newman, Leonard S.; Ambady, Nalini

    2010-01-01

    Previous research has characterized insight as the product of internal processes, and has thus investigated the cognitive and motivational processes that immediately precede it. In this research, however, we investigate whether insight can be catalyzed by a cultural artifact, an external object imbued with learned meaning. Specifically, we exposed participants to an illuminating lightbulb – an iconic image of insight – prior to or during insight problem-solving. Across four studies, exposing participants to an illuminating lightbulb primed concepts associated with achieving an insight, and enhanced insight problem-solving in three different domains (spatial, verbal, and mathematical), but did not enhance general (non-insight) problem-solving. PMID:20652087

  10. DISTANT VIEW, BLM TACK SHED ON LEFT, BLM SEED SHED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DISTANT VIEW, BLM TACK SHED ON LEFT, BLM SEED SHED AT LEFT CENTER, FIRE DISPATCH OFFICES 1 AND 2 AT RIGHT CENTER, UTILITY BUILDING "B" ON RIGHT. VIEW TO SOUTHWEST. - Cedar City Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  11. Shear driven droplet shedding and coalescence on a superhydrophobic surface

    NASA Astrophysics Data System (ADS)

    Moghtadernejad, S.; Tembely, M.; Jadidi, M.; Esmail, N.; Dolatabadi, A.

    2015-03-01

    The interest on shedding and coalescence of sessile droplets arises from the importance of these phenomena in various scientific problems and industrial applications such as ice formation on wind turbine blades, power lines, nacelles, and aircraft wings. It is shown recently that one of the ways to reduce the probability of ice accretion on industrial components is using superhydrophobic coatings due to their low adhesion to water droplets. In this study, a combined experimental and numerical approach is used to investigate droplet shedding and coalescence phenomena under the influence of air shear flow on a superhydrophobic surface. Droplets with a size of 2 mm are subjected to various air speeds ranging from 5 to 90 m/s. A numerical simulation based on the Volume of Fluid method coupled with the Large Eddy Simulation turbulent model is carried out in conjunction with the validating experiments to shed more light on the coalescence of droplets and detachment phenomena through a detailed analysis of the aerodynamics forces and velocity vectors on the droplet and the streamlines around it. The results indicate a contrast in the mechanism of two-droplet coalescence and subsequent detachment with those related to the case of a single droplet shedding. At lower speeds, the two droplets coalesce by attracting each other with successive rebounds of the merged droplet on the substrate, while at higher speeds, the detachment occurs almost instantly after coalescence, with a detachment time decreasing exponentially with the air speed. It is shown that coalescence phenomenon assists droplet detachment from the superhydrophobic substrate at lower air speeds.

  12. Structural analysis of light aircraft using NASTRAN

    NASA Technical Reports Server (NTRS)

    Wilkinson, M. T.; Bruce, A. C.

    1973-01-01

    An application of NASTRAN to the structural analysis of light aircraft was conducted to determine the cost effectiveness. A model of the Baby Ace D model homebuilt aircraft was used. The NASTRAN model of the aircraft consists of 193 grid points connected by 352 structural members. All members are either rod or beam elements, including bending of unsymmetrical cross sections and torsion of noncircular cross sections. The aerodynamic loads applied to the aircraft were in accordance with FAA regulations governing the utility category aircraft.

  13. A Proteomic Approach to Characterize Protein Shedding

    SciTech Connect

    Ahram, Mamoun; Adkins, Joshua N.; Auberry, Deanna L.; Wunschel, David S.; Springer, David L.

    2005-01-01

    Shedding (i.e., proteolysis of ectodomains of membrane proteins) plays an important pathophysiological role. In order to study the feasibility of identifying shed proteins, we analyzed serum-free media of human mammary epithelial cells by mass spectrometry following induction of shedding by the phorbol ester, 4β-phorbol 12-myristate 13-acetate (PMA). Different means of sample preparation, including biotinylation of cell surface proteins, isolation of glycosylated proteins, and preparation of crude protein fraction, were carried out to develop the optimal method of sample processing. The collected proteins were digested with trypsin and analyzed by reversed-phase capillary liquid chromatography interfaced to an ion-trap mass spectrometer. The resulting peptide spectra were interpreted using the program SEQUEST. Analyzing the sample containing the crude protein mixture without chemical modification or separation resulted in the greatest number of identifications, including putatively shed proteins. Overall, 93 membrane-associated proteins were identified including 57 that contain at least one transmembrane domain and 36 that indirectly associate with the extracellular surface of the plasma membrane. Of the 57 transmembrane proteins, 43 were identified by extracellular peptides providing strong evidence for them originating from regulated proteolysis or shedding processes. We combined results from the different experiments and used a peptide count method to estimate changes in protein abundance. Using this approach, we identified 2 proteins, syndecan-4 and hepatoma-derived growth factor, whose abundances increased in media of cells treated with PMA. We also detected proteins whose abundances decreased after PMA treatment such as 78-kDa glucose-regulated protein and calreticulin. Further analysis using immunoblotting validated the abundance changes for syndecan-4 and 78-kDa glucose-regulated protein as a result of PMA treatment. These results demonstrate that mass

  14. A proteomic approach to characterize protein shedding.

    PubMed

    Ahram, Mamoun; Adkins, Joshua N; Auberry, Deanna L; Wunschel, David S; Springer, David L

    2005-01-01

    Shedding (i.e. proteolysis of ectodomains of membrane proteins) plays an important pathophysiological role. In order to study the feasibility of identifying shed proteins, we analyzed serum-free media of human mammary epithelial cells by mass spectrometry following induction of shedding by the phorbol ester, 4 beta-phorbol 12-myristate 13-acetate (PMA). Different means of sample preparation, including biotinylation of cell surface proteins, isolation of glycosylated proteins, and preparation of crude protein fractions, were carried out to develop the optimal method of sample processing. The collected proteins were digested with trypsin and analyzed by reversed-phase capillary liquid chromatography interfaced to an ion-trap mass spectrometer. The resulting peptide spectra were interpreted using the program SEQUEST. Analyzing the sample containing the crude protein mixture without chemical modification or separation resulted in the greatest number of identifications, including putatively shed proteins. Overall, 45 membrane-associated proteins were identified including 22 that contain at least one transmembrane domain and 23 that indirectly associate with the extracellular surface of the plasma membrane. Of the 22 transmembrane proteins, 18 were identified by extracellular peptides providing strong evidence they originate from regulated proteolysis or shedding processes. We combined results from the different experiments and used a peptide count method to estimate changes in protein abundance. Using this approach, we identified two proteins, syndecan-4 and hepatoma-derived growth factor, whose abundances increased in media of cells treated with PMA. We also detected proteins whose abundances decreased after PMA treatment such as 78 kDa glucose-regulated protein and lactate dehydrogenase A. Further analysis using immunoblotting validated the abundance changes for syndecan-4 and 78 kDa glucose-regulated protein as a result of PMA treatment. These results demonstrate

  15. Light-curve Analysis of Neon Novae

    NASA Astrophysics Data System (ADS)

    Hachisu, Izumi; Kato, Mariko

    2016-01-01

    We analyzed light curves of five neon novae, QU Vul, V351 Pup, V382 Vel, V693 CrA, and V1974 Cyg, and determined their white dwarf (WD) masses and distance moduli on the basis of theoretical light curves composed of free-free and photospheric emission. For QU Vul, we obtained a distance of d ˜ 2.4 kpc, reddening of E(B - V) ˜ 0.55, and WD mass of MWD = 0.82-0.96 {M}⊙ . This suggests that an oxygen-neon WD lost a mass of more than ˜ 0.1 {M}⊙ since its birth. For V351 Pup, we obtained d˜ 5.5 {{kpc}}, E(B-V)˜ 0.45, and {M}{{WD}}=0.98-1.1 {M}⊙ . For V382 Vel, we obtained d˜ 1.6 {{kpc}}, E(B-V)˜ 0.15, and {M}{{WD}}=1.13-1.28 {M}⊙ . For V693 CrA, we obtained d˜ 7.1 {{kpc}}, E(B-V)˜ 0.05, and {M}{{WD}}=1.15-1.25 {M}⊙ . For V1974 Cyg, we obtained d˜ 1.8 {{kpc}}, E(B-V)˜ 0.30, and {M}{{WD}}=0.95-1.1 {M}⊙ . For comparison, we added the carbon-oxygen nova V1668 Cyg to our analysis and obtained d˜ 5.4 {{kpc}}, E(B-V)˜ 0.30, and {M}{{WD}}=0.98-1.1 {M}⊙ . In QU Vul, photospheric emission contributes 0.4-0.8 mag at most to the optical light curve compared with free-free emission only. In V351 Pup and V1974 Cyg, photospheric emission contributes very little (0.2-0.4 mag at most) to the optical light curve. In V382 Vel and V693 CrA, free-free emission dominates the continuum spectra, and photospheric emission does not contribute to the optical magnitudes. We also discuss the maximum magnitude versus rate of decline relation for these novae based on the universal decline law.

  16. Light water reactor lower head failure analysis

    SciTech Connect

    Rempe, J.L.; Chavez, S.A.; Thinnes, G.L.

    1993-10-01

    This document presents the results from a US Nuclear Regulatory Commission-sponsored research program to investigate the mode and timing of vessel lower head failure. Major objectives of the analysis were to identify plausible failure mechanisms and to develop a method for determining which failure mode would occur first in different light water reactor designs and accident conditions. Failure mechanisms, such as tube ejection, tube rupture, global vessel failure, and localized vessel creep rupture, were studied. Newly developed models and existing models were applied to predict which failure mechanism would occur first in various severe accident scenarios. So that a broader range of conditions could be considered simultaneously, calculations relied heavily on models with closed-form or simplified numerical solution techniques. Finite element techniques-were employed for analytical model verification and examining more detailed phenomena. High-temperature creep and tensile data were obtained for predicting vessel and penetration structural response.

  17. Transcriptome profiling of petal abscission zone and functional analysis of AUX/IAA family genes reveal that RhIAA16 is involved in petal shedding in rose

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rose is one of the most important cut flowers among ornamental plants. Rose flower longevity is largely dependent on the timing of petal shedding occurrence. To understand the molecular mechanism underlying petal abscission in rose, we performed transcriptome profiling of the petal abscission zone d...

  18. Characterization of CD200 Ectodomain Shedding

    PubMed Central

    Zhu, Fang; Khatri, Ismat; Huo, Qiang; Spaner, David E.; Gorczynski, Reginald M.

    2016-01-01

    We have previously reported the existence of a soluble form of CD200 (sCD200) in human plasma, and found sCD200 to be elevated in the plasma of Chronic Lymphocytic Leukemia (CLL) patients. CLL cells release CD200 at a constitutive level, which could be attenuated partially by ADAM28 silencing. In this study, we further explored mechanisms of CD200 shedding beyond that of ADAM28, and performed biochemical analysis of sCD200 using materials derived from purified CLL cells and Hek293 cells stably transfected with CD200, and antibodies generated specifically against either the extracellular or cytoplasmic regions of CD200. CD200 shedding was enhanced by PMA stimulation, and the loss of cell surface CD200 could be monitored as a reduction in CD200 cell surface expression by flow cytometry, in parallel with an increase in the detection of sCD200 in the supernatant. Western blot analyses and functional studies using CD200R1 expressing Hek293 cells showed that the shed CD200 detected in CLL and Hek293-hCD200 supernatants lacked the cytoplasmic domain of CD200 but retained the functional extracellular domain required for binding to, and phosphorylation of, CD200R. These data confirms that a functionally active CD200 extracellular moiety can be cleaved from the surface of CD200 expressing cells following ectodomain shedding. PMID:27111430

  19. LED intense headband light source for fingerprint analysis

    DOEpatents

    Villa-Aleman, Eliel

    2005-03-08

    A portable, lightweight and high-intensity light source for detecting and analyzing fingerprints during field investigation. On-site field analysis requires long hours of mobile analysis. In one embodiment, the present invention comprises a plurality of light emitting diodes; a power source; and a personal attachment means; wherein the light emitting diodes are powered by the power source, and wherein the power source and the light emitting diodes are attached to the personal attachment means to produce a personal light source for on-site analysis of latent fingerprints. The present invention is available for other applications as well.

  20. Circadian disc shedding in Xenopus retina in vitro

    SciTech Connect

    Flannery, J.G.; Fisher, S.K.

    1984-02-01

    To further examine the endogenous rhythm of disc shedding and phagocytosis observed in several species, adult Xenopus were entrained to a 12 hr light/12 hr dark cycle and then placed in constant darkness. At various times during a 3-day period of constant darkness, eyes were explanted and placed into culture medium, then processed for light and electron microscopy. A clear rhythmicity of disc shedding was observed, with pronounced peaks at the times light onset occurred in the original entrainment cycle. Modification of the HCO/sub 3/- ion concentration in the medium was found to raise the amplitude of the peak of endogenous disc shedding. Explants maintained in culture medium containing deuterium oxide (a compound known to perturb circadian oscillators) were found to shed with a longer interval between peaks. The addition of the protein synthesis inhibitor, anisomycin, to this preparation suppressed the shedding rhythm. The action of anisomycin was investigated by autoradiographic examination of the pattern of /sup 3/H-leucine uptake and protein synthesis by the explant. The findings suggest the presence of a circadian oscillator for rhythmic disc shedding within the amphibian eye.

  1. Aq Psc Analysis of New Light Curves

    NASA Astrophysics Data System (ADS)

    Yamasaki, Atsuma

    2005-04-01

    New BV light curves of the A-type W UMa star AQ Psc (P = 0.476d) have been observed and are described. A few times of minimum light are obtained and the ephemeris is improved. The light curves are analyzed for the binary parameters with a light curve synthesis method. Combining the results with Lu and Rucinski’s spectroscopic mass ratio we determined the masses and radii of the components: M 1 = 1.69M ⊙, M 2 = 0.38M ⊙, R 1 = 1.77R ⊙, and R 2 = 0.89R ⊙.

  2. Transcranial light-tissue interaction analysis

    NASA Astrophysics Data System (ADS)

    Aulakh, Kavleen; Zakaib, Scott; Willmore, William G.; Ye, Winnie N.

    2016-03-01

    The penetration depth of light plays a crucial role in therapeutic medical applications. In order to design effective medical photonic devices, an in-depth understanding of light's ability to penetrate tissues (including bone, skin, and fat) is necessary. The amount of light energy absorbed or scattered by tissues affects the intensity of light reaching an intended target in vivo. In this study, we examine the transmittance of light through a variety of cranial tissues for the purpose of determining the efficacy of neuro stimulation using a transcranial laser. Tissue samples collected from a pig were irradiated with a pulsed laser. We first determine the optimal irradiation wavelength of the laser to be 808nm. With varying peak and average power of the laser, we found an inverse and logarithmic relationship between the penetration depth and the intensity of the light. After penetrating the skin and skull of the pig, the light decreases in intensity at a rate of approximately 90.8 (+/-0.4) percent for every 5 mm of brain tissue penetrated. We also found the correlation between the irradiation time and dosage, using three different lasers (with peak power of 500, 1000, and 1500mW respectively). These data will help deduce what laser power is required to achieve a clinically-realistic model for a given irradiation time. This work is fundamental and the experimental data can be used to supplement existing and future research on the effects of laser light on brain tissue for the design of medical devices.

  3. View Shed - Version 1.0

    Energy Science and Technology Software Center (ESTSC)

    2014-09-18

    The View Shed library is a collection of Umbra modules that are used to calculate areas of visual coverage (view sheds). It maps high and low visibility areas and calculates sensor (camera placement for maximum coverage and performance. This assertion includes a managed C++ wrapper code (ViewShedWrapper) to enable C# applications, such as OpShed, to incorporate this library.

  4. Daylighting and Electric Lighting Analysis for Complex Spaces

    Energy Science and Technology Software Center (ESTSC)

    1995-06-07

    SUPERLITE is a powerful lighting analysis program designed to accurately predict interior illuminance in complex building spaces due to daylight and electric lighting systems. The program enables users to model interior daylight levels for any sun and sky condition in spaces having windows, skylights or other standard fenestration systems. SUPERLITE Version 2.0 includes the capability to calculate electric lighting levels in addition to the daylighting prediction, allowing lighting performance simulation for integrated lighting systems. Themore » program calculates lighting levels on all interior surfaces, as well as on planes that can be arbitrarily positioned to represent work surfaces or other locations of interest. SUPERLITE is intended to be used by researchers and lighting designers who require detailed analysis of the illuminance distribution in architecturally complex spaces.« less

  5. A new light on caloric test--what was disclosed by three dimensional analysis of caloric nystagmus?

    NASA Technical Reports Server (NTRS)

    Arai, Y.

    2001-01-01

    For better understanding of caloric nystagmus, this phenomenon will be reviewed historically in three stages. 1) The first light on caloric nystagmus was thrown by Barany 1906. Through direct observation of eye movements, Barany established the caloric test as an important tool to determine the side of lesion for vertigo. 2) The second light is shed by electrooculogram (EOG) from the late 1950th. EOG enabled qualitative analysis of caloric nystagmus, and proved Barany's convection theory, but resulted in neglect of vertical and roll eye movements. 3) The third light is gained by 3D recording of eye movements started from the late 1980th. 3D recordings of eye movements enabled us to analyze the spatial orientation of caloric nystagmus, and disclose the close correlation of the nystagmus components in the head vertical and the space vertical planes, suggesting a contribution of the velocity storage integrator. The 3D property of caloric nystagmus will be explained in detail.

  6. Analysis of frequency dependent pump light absorption

    NASA Astrophysics Data System (ADS)

    Wohlmuth, Matthias; Pflaum, Christoph

    2011-03-01

    Simulations have to accurately model thermal lensing in order to help improving resonator design of diode pumped solid state lasers. To this end, a precise description of the pump light absorption is an important prerequisite. In this paper, we discuss the frequency dependency of the pump light absorption in the laser crystal and its influence on the simulated laser performance. The results show that the pump light absorption has to include the spectral overlap of the emitting pump source and the absorbing laser material. This information can either be used for a fully frequency dependent absorption model or, at least in the shown examples, to compute an effective value for an exponential Beer-Lambert law of absorption. This is particularly significant at pump wavelengths coinciding with a peak of absorption. Consequences for laser stability and performance are analyzed for different pump wavelengths in a Nd:YAG laser.

  7. Mitochondrial genomes of the jungle crow Corvus macrorhynchos (Passeriformes: Corvidae) from shed feathers and a phylogenetic analysis of genus Corvus using mitochondrial protein-coding genes.

    PubMed

    Krzeminska, Urszula; Wilson, Robyn; Rahman, Sadequr; Song, Beng Kah; Seneviratne, Sampath; Gan, Han Ming; Austin, Christopher M

    2016-07-01

    The complete mitochondrial genomes of two jungle crows (Corvus macrorhynchos) were sequenced. DNA was extracted from tissue samples obtained from shed feathers collected in the field in Sri Lanka and sequenced using the Illumina MiSeq Personal Sequencer. Jungle crow mitogenomes have a structural organization typical of the genus Corvus and are 16,927 bp and 17,066 bp in length, both comprising 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal subunit genes, and a non-coding control region. In addition, we complement already available house crow (Corvus spelendens) mitogenome resources by sequencing an individual from Singapore. A phylogenetic tree constructed from Corvidae family mitogenome sequences available on GenBank is presented. We confirm the monophyly of the genus Corvus and propose to use complete mitogenome resources for further intra- and interspecies genetic studies. PMID:26075478

  8. Shed syndecan-2 inhibits angiogenesis

    PubMed Central

    De Rossi, Giulia; Evans, Alun R.; Kay, Emma; Woodfin, Abigail; McKay, Tristan R.; Nourshargh, Sussan; Whiteford, James R.

    2014-01-01

    ABSTRACT Angiogenesis is essential for the development of a normal vasculature, tissue repair and reproduction, and also has roles in the progression of diseases such as cancer and rheumatoid arthritis. The heparan sulphate proteoglycan syndecan-2 is expressed on mesenchymal cells in the vasculature and, like the other members of its family, can be shed from the cell surface resulting in the release of its extracellular core protein. The purpose of this study was to establish whether shed syndecan-2 affects angiogenesis. We demonstrate that shed syndecan-2 regulates angiogenesis by inhibiting endothelial cell migration in human and rodent models and, as a result, reduces tumour growth. Furthermore, our findings show that these effects are mediated by the protein tyrosine phosphatase receptor CD148 (also known as PTPRJ) and this interaction corresponds with a decrease in active β1 integrin. Collectively, these data demonstrate an unexplored pathway for the regulation of new blood vessel formation and identify syndecan-2 as a therapeutic target in pathologies characterised by angiogenesis. PMID:25179601

  9. Light beam deflector performance: a comparative analysis.

    PubMed

    Zook, J D

    1974-04-01

    The performance of various types of analog light beam deflectors is summarized, and their relative positions in a deflector hierarchy are defined. The three types of deflectors considered are (1) mechanical (galvanometer) mirror deflectors, (2) acoustooptic deflectors, and (3) analog electrooptic deflectors. Material figures of merit are defined and compared, and the theoretical trade-off between speed and resolution is given for each type of deflector. PMID:20126095

  10. Lighting Condition Analysis for Mars Moon Phobos

    NASA Technical Reports Server (NTRS)

    Li, Zu Qun; Crues, Edwin Z.; Bielski, Paul; De Carufel, Guy

    2016-01-01

    A manned mission to Phobos may be an important precursor and catalyst for the human exploration of Mars, as it will fully demonstrate the technologies for a successful Mars mission. A comprehensive understanding of Phobos' environment such as lighting condition and gravitational acceleration are essential to the mission success. The lighting condition is one of many critical factors for landing zone selection, vehicle power subsystem design, and surface mobility vehicle path planning. Due to the orbital characteristic of Phobos, the lighting condition will change dramatically from one Martian season to another. This study uses high fidelity computer simulation to investigate the lighting conditions, specifically the solar radiation flux over the surface, on Phobos. Ephemeris data from the Jet Propulsion Laboratory (JPL) DE405 model was used to model the state of the Sun, the Earth, and Mars. An occultation model was developed to simulate Phobos' self-shadowing and its solar eclipses by Mars. The propagated Phobos' state was compared with data from JPL's Horizon system to ensure the accuracy of the result. Results for Phobos lighting condition over one Martian year are presented in this paper, which include length of solar eclipse, average solar radiation intensity, surface exposure time, total maximum solar energy, and total surface solar energy (constrained by incident angle). The results show that Phobos' solar eclipse time changes throughout the Martian year with the maximum eclipse time occurring during the Martian spring and fall equinox and no solar eclipse during the Martian summer and winter solstice. Solar radiation intensity is close to minimum at the summer solstice and close to maximum at the winter solstice. Total surface exposure time is longer near the north pole and around the anti- Mars point. Total maximum solar energy is larger around the anti-Mars point. Total surface solar energy is higher around the anti-Mars point near the equator. The

  11. Stray light analysis of the Cryogenic Limb Array Etalon Spectrometer

    NASA Technical Reports Server (NTRS)

    Birge, Thomas A.

    1987-01-01

    The stray light analysis performance of the Cryogenic Limb Array Etalon Spectrometer (CLAES), which is to be flown on NASA's Upper Atmospheric Research Satellite, was evaluated using the APART/PADE code, and the results are reported. The analysis, together with Brassboard measurements, confirm that the data to be collected by CLAES should not be significantly degraded by stray light resulting from scattering within the system. It is also verified that diffraction effects are successfully controlled by the cascaded stop configuration.

  12. Lighting Condition Analysis for Mars' Moon Phobos

    NASA Technical Reports Server (NTRS)

    Li, Zu Qun; de Carufel, Guy; Crues, Edwin Z.; Bielski, Paul

    2016-01-01

    This study used high fidelity computer simulation to investigate the lighting conditions, specifically the solar radiation flux over the surface, on Phobos. Ephemeris data from the Jet Propulsion Laboratory (JPL) DE405 model was used to model the state of the Sun, Earth, Moon, and Mars. An occultation model was developed to simulate Phobos' self-shadowing and its solar eclipses by Mars. The propagated Phobos state was compared with data from JPL's Horizon system to ensure the accuracy of the result. Results for Phobos lighting conditions over one Martian year are presented, which include the duration of solar eclipses, average solar radiation intensity, surface exposure time, available energy per unit area for sun tracking arrays, and available energy per unit area for fixed arrays (constrained by incident angle). The results show that: Phobos' solar eclipse time varies throughout the Martian year, with longer eclipse durations during the Martian spring and fall seasons and no eclipses during the Martian summer and winter seasons; solar radiation intensity is close to minimum at the summer solstice and close to maximum at the winter solstice; exposure time per orbit is relatively constant over the surface during the spring and fall but varies with latitude during the summer and winter; and Sun tracking solar arrays generate more energy than a fixed solar array. A usage example of the result is also present in this paper to demonstrate the utility.

  13. Lighting Condition Analysis for Mars' Moon Phobos

    NASA Technical Reports Server (NTRS)

    Li, Zu Qun; de Carufel, Guy; Crues, Edwin Z.; Bielski, Paul

    2016-01-01

    This study used high fidelity computer simulation to investigate the lighting conditions, specifically the solar radiation flux over the surface, on Phobos. Ephemeris data from the Jet Propulsion Laboratory (JPL) DE405 model was used to model the state of the Sun, Earth, Moon, and Mars. An occultation model was developed to simulate Phobos' self-shadowing and its solar eclipses by Mars. The propagated Phobos state was compared with data from JPL's Horizon system to ensure the accuracy of the result. Results for Phobos lighting conditions over one Martian year are presented, which include the duration of solar eclipses, average solar radiation intensity, surface exposure time, and radiant exposure for both sun tracking and fixed solar arrays. The results show that: Phobos' solar eclipse time varies throughout the Martian year, with longer eclipse durations during the Martian northern spring and fall seasons and no eclipses during the Martian northern summer and winter seasons; solar radiation intensity is close to minimum in late spring and close to maximum in late fall; exposure time per orbit is relatively constant over the surface during the spring and fall but varies with latitude during the summer and winter; and Sun tracking solar arrays generate more energy than a fixed solar array. A usage example of the result is also present in this paper to demonstrate the utility.

  14. Study of erythrocyte membrane fluctuation using light scattering analysis

    NASA Astrophysics Data System (ADS)

    Lee, Hoyoon; Lee, Sangyun; Park, YongKeun; Shin, Sehyun

    2016-03-01

    It is commonly known that alteration of erythrocyte deformability lead to serious microcirculatory diseases such as retinopathy, nephropathy, etc. Various methods and technologies have been developed to diagnose such membrane properties of erythrocytes. In this study, we developed an innovative method to measure hemorheological characteristics of the erythrocyte membrane using a light scattering analysis with simplified optic setting and multi-cell analysis as well. Light scattering intensity through multiple erythrocytes and its power density spectrum were obtained. The results of light scattering analyses were compared in healthy control and artificially hardened sample which was treated with glutaraldehyde. These results were further compared with conventional assays to measure deformable property in hemorheology. We found that light scattering information would reflect the disturbance of membrane fluctuation in artificially damaged erythrocytes. Therefore, measuring fluctuation of erythrocyte membrane using light scattering signal could facilitate simple and precise diagnose of pathological state on erythrocyte as well as related complications.

  15. Atmospheric particulate analysis using angular light scattering

    NASA Technical Reports Server (NTRS)

    Hansen, M. Z.

    1980-01-01

    Using the light scattering matrix elements measured by a polar nephelometer, a procedure for estimating the characteristics of atmospheric particulates was developed. A theoretical library data set of scattering matrices derived from Mie theory was tabulated for a range of values of the size parameter and refractive index typical of atmospheric particles. Integration over the size parameter yielded the scattering matrix elements for a variety of hypothesized particulate size distributions. A least squares curve fitting technique was used to find a best fit from the library data for the experimental measurements. This was used as a first guess for a nonlinear iterative inversion of the size distributions. A real index of 1.50 and an imaginary index of -0.005 are representative of the smoothed inversion results for the near ground level atmospheric aerosol in Tucson.

  16. Analysis of NHANES measured blood PCBs in the general US population and application of SHEDS model to identify key exposure factors.

    PubMed

    Xue, Jianping; Liu, Shi V; Zartarian, Valerie G; Geller, Andrew M; Schultz, Bradley D

    2014-11-01

    Studies have shown that the US population continues to be exposed to polychlorinated biphenyls (PCBs), despite their ban more than three decades ago, but the reasons are not fully understood. The objectives of this paper are to characterize patterns of PCBs in blood by age, gender, and ethnicity, and identify major exposure factors. EPA's Stochastic Human Exposure and Dose Simulation (SHEDS)-dietary exposure model was applied, combining fish tissue PCB levels from a NYC Asian Market survey with National Health and Nutrition Examination Survey (NHANES) dietary consumption data, and then linked with blood biomarkers for the same NHANES study subjects. Results reveal that the mean concentration of total PCBs in blood was higher with increasing age; however, for the same age, gender, and ethnicity, the blood PCB concentrations measured in the later NHANES survey were significantly lower than those in the earlier one. The decrease within an age group between the two survey periods lessened with increasing age. Blood PCBs among different ethnicities ranked differently between the older and the younger age groups within each survey. Non-Hispanic Blacks had significantly higher blood PCBs for the >30 year age group. For the 12 to ≤30 year age group, the "Asian, Pacific Islander, Native American or multiracial" group had the highest values, with patterns fairly consistent with fish consumption and modeled PCB exposure patterns. We conclude that for younger people, patterns correspond to reduced environmental contamination over time, and are strongly associated with fish consumption and dietary exposures. Higher PCB concentrations in blood of the older population may partially reflect past exposures to higher environmental PCB concentrations, particularly before the ban. PMID:24424407

  17. Thermodynamic analysis of quantum light amplification

    NASA Astrophysics Data System (ADS)

    Boukobza, E.; Tannor, D. J.

    2006-12-01

    Thermodynamics of a three-level maser was studied in the pioneering work of Scovil and Schulz-DuBois [Phys. Rev. Lett. 2, 262 (1959)]. In this work we consider the same three-level model, but treat both the matter and the light quantum mechanically. Specifically, we analyze an extended (three-level) dissipative (ED) Jaynes-Cummings model (JCM) within the framework of a quantum heat engine, using formulas for heat flux and power in bipartite systems introduced in our previous work [E. Boukobza and D. J. Tannor Phys. Rev. A 74, 063823 (2006)] Amplification of the selected cavity mode occurs even in this simple model, as seen by a positive steady state power. However, initial field coherence is lost, as seen by the decaying off-diagonal field density matrix elements, and by the Husimi-Kano Q function. We show that after an initial transient time the field’s entropy rises linearly during the operation of the engine, which we attribute to the dissipative nature of the evolution and not to matter-field entanglement. We show that the second law of thermodynamics is satisfied in two formulations (Clausius, Carnot) and that the efficiency of the ED JCM heat engine agrees with that defined intuitively by Scovil and Schulz-DuBois. Finally, we compare the steady state heat flux and power of the fully quantum model with the semiclassical counterpart of the ED JCM, and derive the engine efficiency formula of Scovil and Schulz-DuBois analytically from fundamental thermodynamic fluxes.

  18. Near field light intensity distribution analysis in bimodal polymer waveguide

    NASA Astrophysics Data System (ADS)

    Herzog, T.; Gut, K.

    2015-12-01

    The paper presents analysis of light intensity distribution and sensitivity in differential interferometer based on bimodal polymer waveguide. Key part is analysis of optimal waveguide layer thickness in structure SiO2/SU-8/H2O for maximum bulk refractive index sensitivity. The paper presents new approach to detecting phase difference between modes through registrations only part of energy propagating in the waveguide. Additionally in this paper the analysis of changes in light distribution when energy in modes is not equal were performed.

  19. Light curve demography via Bayesian functional data analysis

    NASA Astrophysics Data System (ADS)

    Loredo, Thomas; Budavari, Tamas; Hendry, Martin A.; Kowal, Daniel; Ruppert, David

    2015-08-01

    Synoptic time-domain surveys provide astronomers, not simply more data, but a different kind of data: large ensembles of multivariate, irregularly and asynchronously sampled light curves. We describe a statistical framework for light curve demography—optimal accumulation and extraction of information, not only along individual light curves as conventional methods do, but also across large ensembles of related light curves. We build the framework using tools from functional data analysis (FDA), a rapidly growing area of statistics that addresses inference from datasets that sample ensembles of related functions. Our Bayesian FDA framework builds hierarchical models that describe light curve ensembles using multiple levels of randomness: upper levels describe the source population, and lower levels describe the observation process, including measurement errors and selection effects. Schematically, a particular object's light curve is modeled as the sum of a parameterized template component (modeling population-averaged behavior) and a peculiar component (modeling variability across the population), subsequently subjected to an observation model. A functional shrinkage adjustment to individual light curves emerges—an adaptive, functional generalization of the kind of adjustments made for Eddington or Malmquist bias in single-epoch photometric surveys. We are applying the framework to a variety of problems in synoptic time-domain survey astronomy, including optimal detection of weak sources in multi-epoch data, and improved estimation of Cepheid variable star luminosities from detailed demographic modeling of ensembles of Cepheid light curves.

  20. Vortex shedding and Maxwell's problem

    NASA Astrophysics Data System (ADS)

    Michelin, Sebastien; Smith, Stefan Llewellyn

    2006-11-01

    The coupled problem of a flow around a solid body has applications from the fall of objects in a fluid to the computation of forces on wind-exposed structures. A simplified 2D model is proposed here for the interaction between solid bodies and potential flows. Potential flows over sharp edges generate singular velocities at the edges. To satisfy the Kutta condition, vorticity sheets must be shed from the edges to remove these singularities. Here 2D vorticity sheets are represented as discrete point-vortices with monotically varying intensity. From the fluid momentum conservation, an equation of motion for these vortices, the Brown and Michael equation, is derived and mechanical efforts applied by the fluid on the body are computed. The set of dynamical equations obtained for the fluid-body system is closed and is applied to Maxwell's problem of the 2D fall of a plate in an inviscid fluid initially at rest.

  1. High sensitivity vortex shedding flowmeter

    SciTech Connect

    Lew, H.S.

    1989-12-05

    This patent describes an apparatus for measuring fluid flows. It comprises: a flowmeter body including a flow passage; a vortex generator of an elongated cylindrical shape disposed across a cross section of the flow passage, wherein at lest one extremity of the vortex generator is secured to the flowmeter body; a transducer contained in a container vessel secured to the flowmeter body, wherein the transducer is pressed onto a thin wall of the container vessel; and a flexible coupling connecting the thin wall of the container vessel to a deflective portion of the vortex generating, wherein the flexible coupling enhances relative deflection between the vortex generator and the container vessel. Wherein fluctuating fluid dynamic forces resulting from vortices shed from the vortex generator and experienced by vortex generator generate fluctuating electrical signals from the transducer as a measure of fluid flow through the flow passage.

  2. Lighting.

    SciTech Connect

    United States. Bonneville Power Administration.

    1992-09-01

    Since lighting accounts for about one-third of the energy used in commercial buildings, there is opportunity to conserve. There are two ways to reduce lighting energy use: modify lighting systems so that they used less electricity and/or reduce the number of hours the lights are used. This booklet presents a number of ways to do both. Topics covered include: reassessing lighting levels, reducing lighting levels, increasing bulb & fixture efficiency, using controls to regulate lighting, and taking advantage of daylight.

  3. Automated dimensional analysis using a light-sectioning microscope

    SciTech Connect

    Loomis, J.; Lightman, A.; Poe, A.; Caldwell, R.

    1988-12-31

    A computer vision system has been integrated with a modified light-sectioning microscope for quality control and inspection of a machined part whose critical dimensions are 30 to 300 {mu}m. Height measurements were determined by analysis of the projected light-section line. Transverse measurements were made using the microscope in a traditional configuration with illumination from selected elements of an external LED ring array. The light section irradiance was under computer control to accommodate the spatial variations in surface reflectance whose dynamic range exceeded that of the vision system. Part features are located by the vision system. Edges and line centers are then measured to sub-pixel resolution with a gray-level analysis algorithm. This paper describes the design and operation of this system. Details of the measurement process and analysis algorithms are provided.

  4. Gamma Detector Response and Analysis Software - Light

    Energy Science and Technology Software Center (ESTSC)

    2004-06-14

    GADRAS is used to analyze gamma-ray spectra, which may be augmented by neutron count rate information. The fundamental capabilities of GADRAS are imparted by physics-based detector response functions for a variety of gamma ray and neufron detectors. The software has provisions for characterizing detector response parameters so that specta can be computed accurately over the range 30keV key to II MeV. Associated neutron detector count rates can also be computed for characterized detectors. GADRAS incorporatesmore » a variety of analysis algorithms that utilize the computed spectra. The full version of GADRAS incorporates support for computation of radiation leakages from complex source models, but this capability is not supported by GADRAS-LT. GADRAS has been and will continue to be disseminated free of charge to government agencies and National Laboratories as OUO software. GADRAS-LT is a limited software version that was prepared for exclusive use of our Technology Transfer parnter Thermo Electron (TE). TE will use the software to characterize and test radiation detectors that are fabricated under the terms of our partnership. The development of these sensors has been defined as a National Security priority by our sponsor, NNSA/NA-20, by DHS/S&T, and by SNL president Paul Robinson. Although GADRAS-LT is OUO, features that are not essential to the detector development have been removed. TE will not be licensed to commercialize GADRAS-LT or to distribute it to third parties.« less

  5. Light-induced voltage alteration for integrated circuit analysis

    DOEpatents

    Cole, Jr., Edward I.; Soden, Jerry M.

    1995-01-01

    An apparatus and method are described for analyzing an integrated circuit (IC), The invention uses a focused light beam that is scanned over a surface of the IC to generate a light-induced voltage alteration (LIVA) signal for analysis of the IC, The LIVA signal may be used to generate an image of the IC showing the location of any defects in the IC; and it may be further used to image and control the logic states of the IC. The invention has uses for IC failure analysis, for the development of ICs, for production-line inspection of ICs, and for qualification of ICs.

  6. Light-induced voltage alteration for integrated circuit analysis

    DOEpatents

    Cole, E.I. Jr.; Soden, J.M.

    1995-07-04

    An apparatus and method are described for analyzing an integrated circuit (IC). The invention uses a focused light beam that is scanned over a surface of the IC to generate a light-induced voltage alteration (LIVA) signal for analysis of the IC. The LIVA signal may be used to generate an image of the IC showing the location of any defects in the IC; and it may be further used to image and control the logic states of the IC. The invention has uses for IC failure analysis, for the development of ICs, for production-line inspection of ICs, and for qualification of ICs. 18 figs.

  7. Cepheid light curve demography via Bayesian functional data analysis

    NASA Astrophysics Data System (ADS)

    Loredo, Thomas J.; Hendry, Martin; Kowal, Daniel; Ruppert, David

    2016-01-01

    Synoptic time-domain surveys provide astronomers, not simply more data, but a different kind of data: large ensembles of multivariate, irregularly and asynchronously sampled light curves. We describe a statistical framework for light curve demography—optimal accumulation and extraction of information, not only along individual light curves as conventional methods do, but also across large ensembles of related light curves. We build the framework using tools from functional data analysis (FDA), a rapidly growing area of statistics that addresses inference from datasets that sample ensembles of related functions. Our Bayesian FDA framework builds hierarchical models that describe light curve ensembles using multiple levels of randomness: upper levels describe the source population, and lower levels describe the observation process, including measurement errors and selection effects. Roughly speaking, a particular object's light curve is modeled as the sum of a parameterized template component (modeling population-averaged behavior) and a peculiar component (modeling variability across the population), subsequently subjected to an observation model. A functional shrinkage adjustment to individual light curves emerges—an adaptive, functional generalization of the kind of adjustments made for Eddington or Malmquist bias in single-epoch photometric surveys. We describe ongoing work applying the framework to improved estimation of Cepheid variable star luminosities via FDA-based refinement and generalization of the Cepheid period-luminosity relation.

  8. Teaching meta-analysis using MetaLight

    PubMed Central

    2012-01-01

    Background Meta-analysis is a statistical method for combining the results of primary studies. It is often used in systematic reviews and is increasingly a method and topic that appears in student dissertations. MetaLight is a freely available software application that runs simple meta-analyses and contains specific functionality to facilitate the teaching and learning of meta-analysis. While there are many courses and resources for meta-analysis available and numerous software applications to run meta-analyses, there are few pieces of software which are aimed specifically at helping those teaching and learning meta-analysis. Valuable teaching time can be spent learning the mechanics of a new software application, rather than on the principles and practices of meta-analysis. Findings We discuss ways in which the MetaLight tool can be used to present some of the main issues involved in undertaking and interpreting a meta-analysis. Conclusions While there are many software tools available for conducting meta-analysis, in the context of a teaching programme such software can require expenditure both in terms of money and in terms of the time it takes to learn how to use it. MetaLight was developed specifically as a tool to facilitate the teaching and learning of meta-analysis and we have presented here some of the ways it might be used in a training situation. PMID:23078762

  9. Stray-light analysis of the SABER telescope

    NASA Astrophysics Data System (ADS)

    Stauder, John; Esplin, Roy W.; Zollinger, Lorin; Mlynczak, Martin G.; Russell, James M.; Gordley, Larry L.; Marshall, Tom

    1995-09-01

    The stray light analysis of the sounding of the atmosphere using broadband emission radiometry (SABER) instrument on the thermosphere-ionosphere-mesosphere energetics and dynamics (TIMED) mission is discussed. Relevant mission objectives and operating conditions are stated to define the stray light problem. Since SABER is an earth limb viewing sensor, the telescope must be designed for large off-axis rejection. Described are the key design features which make the instrument well suited for its mission. Representative point source transmittance (PST) curves computed using the commercial stray light program APART are presented. Nonrejected radiance (NRR) values computed using APART generated PST curves and LINEPACK generated curves for the total radiance from the earth and the atmosphere are given. A method for computing NRR from the earth and the atmosphere using line-of-sight radiance profiles versus tangent height is described. Computed NRR values demonstrate that the effect of stray light on SABER's measurement capability is negligible.

  10. Dynamic deformation analysis of light-weight mirror

    NASA Astrophysics Data System (ADS)

    Zhang, Yingtao; Cao, Xuedong; Kuang, Long; Yang, Wei

    2012-10-01

    In the process of optical dynamic target work, under the effort of the arm of dynamic target, the mirror needs to do circular motion, additional accelerated motion and uniform motion. The maximum acceleration is 10°/s2 and the maximum velocity is 30°/s. In this paper, we mostly analyze the dynamic deformation of a 600 mm honeycomb light-weight mirror of a certain dynamic target. Using the FEA (finite element analysis) method, first of all, we analyze the deformation of the light-weight mirror induced in gravity at different position; later, the dynamic deformation of light-weight mirror is analyzed in detailed. The analysis results indicate that, when the maximum acceleration is 10°/s2 and the maximum velocity is 30°/s, the centripetal force is 5% of the gravity at the equal mass, and the dynamic deformation of the mirror is 6.1% of the deformation induced by gravity.

  11. Energy Star Lighting Verification Program (Program for the Evaluation and Analysis of Residential Lighting)

    SciTech Connect

    Conan O'Rourke; Yutao Zhou

    2006-03-01

    The Program for the Evaluation and Analysis of Residential Lighting (PEARL) is a watchdog program. It was created in response to complaints received by utility program managers about the performance of certain Energy Star lighting products being promoted within their service territories and the lack of a self-policing mechanism within the lighting industry that would ensure the reliability of these products and their compliance with ENERGY STAR specifications. To remedy these problems, PEARL purchases and tests products that are available to the consumers in the marketplace. The Lighting Research Center (LRC) tests the selected products against the corresponding Energy Star specifications. This report includes the experimental procedure and data results of Cycle Three of PEARL program during the period of October 2002 to April 2003, along with the description of apparatus used, equipment calibration process, experimental methodology, and research findings from the testing. The products tested are 20 models of screw-based compact fluorescent lamps (CFL) of various types and various wattages made or marketed by 12 different manufacturers, and ten models of residential lighting fixtures from eight different manufacturers.

  12. 24. 'HANGAR SHEDS ELEVATIONS DETAILS; ARCHITECTURAL PLANS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. 'HANGAR SHEDS - ELEVATIONS - DETAILS; ARCHITECTURAL PLANS - PLANT AREA; MODIFICATION CENTER NO. 1, DAGGETT, CALIFORNIA.' Partial elevations, and details of sliding doors and ventilator flaps, as built. Contract no. W509 Eng. 2743; File no. 555/81, revision B, dated April 6, 1943. No sheet number. - Barstow-Daggett Airport, Hangar Shed No. 4, 39500 National Trails Highway, Daggett, San Bernardino County, CA

  13. Energy Star Lighting Verification Program (Program for the Evaluation and Analysis of Residential Lighting)

    SciTech Connect

    Conan O'Rourke; Yutao Zhou

    2006-05-01

    The Program for the Evaluation and Analysis of Residential Lighting (PEARL) is a watchdog program. It was created in response to complaints received by utility program managers about the performance of certain Energy Star lighting products being promoted within their service territories and the lack of a self-policing mechanism within the lighting industry that would ensure the reliability of these products and their compliance with ENERGY STAR specifications. To remedy these problems, PEARL purchases and tests products that are available to the consumers in the marketplace. The Lighting Research Center (LRC) tests the selected products against the corresponding Energy Star specifications. This report includes the experimental procedure of Cycle 7 of PEARL program during the period of October 2005 to March 2006, along with the description of apparatus used, equipment calibration process, experimental methodology, and research findings from the testing. LRC administered the purchasing of CFL samples to test in Cycle 7, performed 100-hour seasoning for most of the CFL samples received by March 2006, and performed sphere testing for some of the CFL samples at 100 hours of life (initial measurement).

  14. Energy Star Lighting Verification Program (Program for the Evaluation and Analysis of Residential Lighting)

    SciTech Connect

    Conan O'Rourke; Yutao Zhou

    2006-03-01

    The Program for the Evaluation and Analysis of Residential Lighting (PEARL) is a watchdog program. It was created in response to complaints received by utility program managers about the performance of certain Energy Star lighting products being promoted within their service territories and the lack of a self-policing mechanism within the lighting industry that would ensure the reliability of these products and their compliance with ENERGY STAR specifications. To remedy these problems, PEARL purchases and tests products that are available to the consumers in the marketplace. The Lighting Research Center (LRC) tests the selected products against the corresponding Energy Star specifications. This report includes the experimental procedure and data results of Cycle Six of PEARL program during the period of October 2004 to April 2005, along with the description of apparatus used, equipment calibration process, experimental methodology, and research findings from the testing. The parameters tested for CFL models in Cycle Six are 1000-hour Lumen Maintenance, Lumen Maintenance at 40% Rated Life, and Interim Life Test, along with a series of parameters verified, such as ballast electrical parameters and Energy Star label.

  15. Energy Star Lighting Verification Program (Program for the Evaluation and Analysis of Residential Lighting)

    SciTech Connect

    Conan O'Rourke; Yutao Zhou

    2006-03-01

    The Program for the Evaluation and Analysis of Residential Lighting (PEARL) is a watchdog program. It was created in response to complaints received by utility program managers about the performance of certain Energy Star lighting products being promoted within their service territories and the lack of a self-policing mechanism within the lighting industry that would ensure the reliability of these products and their compliance with ENERGY STAR specifications. To remedy these problems, PEARL purchases and tests products that are available to the consumers in the marketplace. The Lighting Research Center (LRC) tests the selected products against the corresponding Energy Star specifications. This report includes the experimental procedure and data results of Cycle Four and Cycle Five of PEARL program during the period of October 2003 to April 2004, along with the description of apparatus used, equipment calibration process, experimental methodology, and research findings from the testing. The parameter tested for Cycle Four is lumen maintenance at 40% rated life, and parameters tested for Cycle Five are all parameters required in Energy Star specifications except lumen maintenance at 40% rated life.

  16. Energy Star Lighting Verification Program (Program for the Evaluation and Analysis of Residential Lighting)

    SciTech Connect

    Conan O'Rourke; Yutao Zhou

    2006-03-01

    The Program for the Evaluation and Analysis of Residential Lighting (PEARL) is a watchdog program. It was created in response to complaints received by utility program managers about the performance of certain Energy Star lighting products being promoted within their service territories and the lack of a self-policing mechanism within the lighting industry that would ensure the reliability of these products and their compliance with ENERGY STAR specifications. To remedy these problems, PEARL purchases and tests products that are available to the consumers in the marketplace. The Lighting Research Center (LRC) tests the selected products against the corresponding Energy Star specifications. This report includes the experimental procedure and data results of Cycle Five and Cycle Six of PEARL program during the period of April 2004 to October 2004, along with the description of apparatus used, equipment calibration process, experimental methodology, and research findings from the testing. The parameter tested for Cycle Five is lumen maintenance at 40% rated life, and parameters tested for Cycle Six are Efficacy, CCT, CRI, Power Factor, Start Time, Warm-up Time, and Rapid Cycle Stress Test for CFLs.

  17. Energy Star Lighting Verification Program (Program for the Evaluation and Analysis of Residential Lighting)

    SciTech Connect

    Conan O'Rourke; Yutao Zhou

    2006-03-01

    The Program for the Evaluation and Analysis of Residential Lighting (PEARL) is a watchdog program. It was created in response to complaints received by utility program managers about the performance of certain Energy Star lighting products being promoted within their service territories and the lack of a self-policing mechanism within the lighting industry that would ensure the reliability of these products and their compliance with ENERGY STAR specifications. To remedy these problems, PEARL purchases and tests products that are available to the consumers in the marketplace. The Lighting Research Center (LRC) tests the selected products against the corresponding Energy Star specifications. This report includes the experimental procedure and data results of Cycle Three and Cycle Four of PEARL program during the period of April 2003 to October 2003, along with the description of apparatus used, equipment calibration process, experimental methodology, and research findings from the testing. The parameter tested for Cycle three is lumen maintenance at 40% rated life, and parameters tested for Cycle Four are all parameters required in Energy Star specifications except lumen maintenance at 40% rated life.

  18. Energy Star Lighting Verification Program (Program for the Evaluation and Analysis of Residential Lighting)

    SciTech Connect

    Conan O'Rourke; Yutao Zhou

    2006-03-01

    The Program for the Evaluation and Analysis of Residential Lighting (PEARL) is a watchdog program. It was created in response to complaints received by utility program managers about the performance of certain Energy Star lighting products being promoted within their service territories and the lack of a self-policing mechanism within the lighting industry that would ensure the reliability of these products and their compliance with ENERGY STAR specifications. To remedy these problems, PEARL purchases and tests products that are available to the consumers in the marketplace. The Lighting Research Center (LRC) tests the selected products against the corresponding Energy Star specifications. This report includes the experimental procedure and data results of Cycle 6 and Reflector CFL In-situ Testing of PEARL program during the period of April 2005 to October 2005, along with the description of apparatus used, equipment calibration process, experimental methodology, and research findings from the testing. LRC performed testing for the fixture samples in Cycle 6 against Energy Star residential fixture specifications during this period of time. LRC subcontracted the Reflector CFL In-situ Testing to Luminaire Testing Laboratories located at Allentown PA, and supervised this test.

  19. Immunoglobulin analysis tool: a novel tool for the analysis of human and mouse heavy and light chain transcripts.

    PubMed

    Rogosch, Tobias; Kerzel, Sebastian; Hoi, Kam Hon; Zhang, Zhixin; Maier, Rolf F; Ippolito, Gregory C; Zemlin, Michael

    2012-01-01

    Sequence analysis of immunoglobulin (Ig) heavy and light chain transcripts can refine categorization of B cell subpopulations and can shed light on the selective forces that act during immune responses or immune dysregulation, such as autoimmunity, allergy, and B cell malignancy. High-throughput sequencing yields Ig transcript collections of unprecedented size. The authoritative web-based IMGT/HighV-QUEST program is capable of analyzing large collections of transcripts and provides annotated output files to describe many key properties of Ig transcripts. However, additional processing of these flat files is required to create figures, or to facilitate analysis of additional features and comparisons between sequence sets. We present an easy-to-use Microsoft(®) Excel(®) based software, named Immunoglobulin Analysis Tool (IgAT), for the summary, interrogation, and further processing of IMGT/HighV-QUEST output files. IgAT generates descriptive statistics and high-quality figures for collections of murine or human Ig heavy or light chain transcripts ranging from 1 to 150,000 sequences. In addition to traditionally studied properties of Ig transcripts - such as the usage of germline gene segments, or the length and composition of the CDR-3 region - IgAT also uses published algorithms to calculate the probability of antigen selection based on somatic mutational patterns, the average hydrophobicity of the antigen-binding sites, and predictable structural properties of the CDR-H3 loop according to Shirai's H3-rules. These refined analyses provide in-depth information about the selective forces acting upon Ig repertoires and allow the statistical and graphical comparison of two or more sequence sets. IgAT is easy to use on any computer running Excel(®) 2003 or higher. Thus, IgAT is a useful tool to gain insights into the selective forces and functional properties of small to extremely large collections of Ig transcripts, thereby assisting a researcher to mine a data set

  20. An analysis of synteny of Arachis with Lotus and Medicago sheds new light on the structure, stability and evolution of legume genomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most agriculturally important legumes fall within the phaseoloids (containing beans) and galegoids (containing peas and clovers). A notable exception is peanut (Arachis hypogaea) which comes from a basally diverged tropical lineage. To improve our understanding of the Arachis genome, single-copy g...

  1. Vortex shedding flowmeter with fiber optic sensor

    NASA Astrophysics Data System (ADS)

    Wroblewski, D. J.; Skuratovsky, E.

    Vortex shedding flow meters have proved over the last decade to be suitable for a wide variety of applications. They provide good accuracy, reliable flow measurement in a wide range of flow rates, and low pressure drop. Past performance was limited to operating pressures equivalent to ANSI Class 600 and process temperatures below 400 C. This paper presents a new design of vortex shedding flow meter with a fiber optic sensor capable of operating at pressures equivalent to ANSI Class 2500 and temperatures from -200 to 600 C. This device opens new horizons for vortex shedding flow meters in flow measurements and process control applications.

  2. Development of an image-analysis light-scattering technique

    NASA Astrophysics Data System (ADS)

    Algarni, Saad; Kashuri, Hektor; Iannacchione, Germano

    2013-03-01

    We describe the progress in developing a versatile image-analysis approach for a light-scattering experiment. Recent advances in image analysis algorithms, computational power, and CCD image capture has allowed for the complete digital recording of the scattering of coherent laser light by a wide variety of samples. This digital record can then yield both static and dynamic information about the scattering events. Our approach is described using a very simple and in-expensive experimental arrangement for liquid samples. Calibration experiments were performed on aqueous suspensions of latex spheres having 0.5 and 1.0 micrometer diameter for three concentrations of 2 X 10-6, 1 X 10-6, and 5 X 10-7 % w/w at room temperature. The resulting data span a wave-vector range of q = 102 to 105 cm-1 and time averages over 0.05 to 1200 sec. The static analysis yield particle sizes in good agreement with expectations and a simple dynamic analysis yields an estimate of the characteristic time scale of the particle dynamics. Further developments in image corrections (laser stability, vibration, curvature, etc.) as well as time auto-correlation analysis will also be discussed.

  3. Light extraction analysis of GaN-based light-emitting diodes with surface texture and/or patterned substrate.

    PubMed

    Lee, Tsung-Xian; Gao, Ko-Fon; Chien, Wei-Ting; Sun, Ching-Cherng

    2007-05-28

    Light extraction analysis of GaN-based light-emitting diodes (LEDs) with Monte Carlo ray tracing is presented. To obtain high light extraction efficiency, periodic structures introduced on the top surface and/or on the substrate of various types of LED are simulated, including wire bonding, flip chip and Thin GaN. Micro pyramid array with an apex angle from 20o to 70o is shown to effectively improve the light extraction efficiency. In addition, for an LED encapsulated within an epoxy lens, the patterned substrate with pyramid array is found to be a more effective way to increase light extraction efficiency than the surface texture. PMID:19546977

  4. Light microscopic hair shaft analysis in ectodermal dysplasia syndromes.

    PubMed

    Hirano, Stefanie A; Mason, Ashley R; Salkey, Kimberly; Williams, Judith V; Pariser, David M

    2012-01-01

    The objective of the study was to catalog hair shaft abnormalities in individuals with ectodermal dysplasia (ED) syndromes using light microscopy and to compare findings with those in unaffected controls. Light microscopy was performed in a nonblinded manner on hair shafts from 65 participants with seven types of ED (hypohidrotic ED, ED-ectrodactyly-cleft lip or palate, ankyloblepharon-ectodermal defects-cleft lip and palate, Clouston syndrome, Goltz syndrome, Schopf-Schulz Passarge syndrome, and oculodentodigital dysplasia) and 41 unaffected controls. Hair donations were collected at the 28th Annual National Family Conference held by the National Foundation for Ectodermal Dysplasia. Control participants were recruited from a private dermatology practice and an academic children's hospital outpatient dermatology clinic. Sixty-five affected participants and 41 unaffected controls were included in the analysis. We assessed the hair shafts of ED and control participants for abnormalities visible using LM. Light microscopy identified various pathologic hair shaft abnormalities in each type of ED, although none of the findings were statistically significantly different from those of the control group. Light microscopy is a poor adjuvant tool in the diagnosis of ED syndromes. Most findings are nonspecific and not sufficiently sensitive. PMID:22084904

  5. Laser light scan analysis of the “anticonvulsant face”

    PubMed Central

    Orup, H. Ivan; Deutsch, Curtis K.; Holmes, Lewis B.

    2014-01-01

    BACKGROUND The “anticonvulsant face”, comprised of a short nose, low nasal bridge, epicanthal folds, and wide mouth, was suggested in the 1970s to indicate teratogenesis caused by the anticonvulsant drugs phenytoin and phenobarbital. However, these were based on subjective clinical observations. In the present study we have applied objective and reliable quantitative measures to the operational definitions of craniofacial features in anticonvulant-exposed cases. We have adopted anthropometric analysis based on image analysis of laser light scans. Using morphometric methods, we established the positions of physical features and objectively determined the changes in the size and shape of affected soft tissues of the faces of children exposed to those anticonvulsant drugs during pregnancy. METHODS Thirteen individuals, exposed throughout pregnancy to phenytoin as either monotherapy or polytherapy, were identified in a previous analysis as having significant changes in their craniofacial features based on measurements of cephalometric radiographs, changes associated with “the anticonvulsant face”.. The soft tissues of their faces were imaged by 3D laser (structured light) scanning. RESULTS The notable changes in soft tissues identified by laser light scans were a wide philtrum (between the left and right cristae philtri), narrow mouth (between the left and right cheilions), short nasal bridge (between nasale and pronasale), short nose height (between the nasale and subnasale), and flat orbits (based on the orbital protrusion index). CONCLUSIONS This analysis of phenytoin-exposed individuals is the first anthropometric analysis of the craniofacial surface, designed to render the identification of abnormal features both objective and realiable. These analyses demonstrated that there were several significant changes in the soft tissue of the face, corroborating earlier studies of alterations of the craniofacial skeleton in the anticonvulsant face. Two of the

  6. Shedding LITE on global climate

    SciTech Connect

    O`Connor, L.

    1995-04-01

    This article describes the Space Shuttle Discovery mission to carry a lidar-based sensing system that measured cloud formation and atmospheric conditions and transmitted the data to ground sites in 20 countries. The National Aeronautics and Space Administration (NASA) has developed the Lidar In-space Technology Experiment (LITE), a laser-based sensing system carried roughly 160 miles above the earth in the cargo bay of the Space Shuttle Discovery. In the mission, which ran for 10 days last September, the LITE instrument used lidar (light identification, detection, and ranging) for the first time ever to measure cloud cover and atmospheric conditions. This data, which the system transmitted to ground sites, is expected to provide new insights into how clouds affect global climate.

  7. RNA Interference-Mediated Repression of MtCCD1 in Mycorrhizal Roots of Medicago truncatula Causes Accumulation of C27 Apocarotenoids, Shedding Light on the Functional Role of CCD11[W][OA

    PubMed Central

    Floss, Daniela S.; Schliemann, Willibald; Schmidt, Jürgen; Strack, Dieter; Walter, Michael H.

    2008-01-01

    Tailoring carotenoids by plant carotenoid cleavage dioxygenases (CCDs) generates various bioactive apocarotenoids. Recombinant CCD1 has been shown to catalyze symmetrical cleavage of C40 carotenoid substrates at 9,10 and 9′,10′ positions. The actual substrate(s) of the enzyme in planta, however, is still unknown. In this study, we have carried out RNA interference (RNAi)-mediated repression of a Medicago truncatula CCD1 gene in hairy roots colonized by the arbuscular mycorrhizal (AM) fungus Glomus intraradices. As a consequence, the normal AM-mediated accumulation of apocarotenoids (C13 cyclohexenone and C14 mycorradicin derivatives) was differentially modified. Mycorradicin derivatives were strongly reduced to 3% to 6% of the controls, while the cyclohexenone derivatives were only reduced to 30% to 47%. Concomitantly, a yellow-orange color appeared in RNAi roots. Based on ultraviolet light spectra and mass spectrometry analyses, the new compounds are C27 apocarotenoic acid derivatives. These metabolic alterations did not lead to major changes in molecular markers of the AM symbiosis, although a moderate shift to more degenerating arbuscules was observed in RNAi roots. The unexpected outcome of the RNAi approach suggests C27 apocarotenoids as the major substrates of CCD1 in mycorrhizal root cells. Moreover, literature data implicate C27 apocarotenoid cleavage as the general functional role of CCD1 in planta. A revised scheme of plant carotenoid cleavage in two consecutive steps is proposed, in which CCD1 catalyzes only the second step in the cytosol (C27 → C14 + C13), while the first step (C40 → C27 + C13) may be catalyzed by CCD7 and/or CCD4 inside plastids. PMID:18790999

  8. Economic Analysis of Greenhouse Lighting: Light Emitting Diodes vs. High Intensity Discharge Fixtures

    PubMed Central

    Nelson, Jacob A.; Bugbee, Bruce

    2014-01-01

    Lighting technologies for plant growth are improving rapidly, providing numerous options for supplemental lighting in greenhouses. Here we report the photosynthetic (400–700 nm) photon efficiency and photon distribution pattern of two double-ended HPS fixtures, five mogul-base HPS fixtures, ten LED fixtures, three ceramic metal halide fixtures, and two fluorescent fixtures. The two most efficient LED and the two most efficient double-ended HPS fixtures had nearly identical efficiencies at 1.66 to 1.70 micromoles per joule. These four fixtures represent a dramatic improvement over the 1.02 micromoles per joule efficiency of the mogul-base HPS fixtures that are in common use. The best ceramic metal halide and fluorescent fixtures had efficiencies of 1.46 and 0.95 micromoles per joule, respectively. We also calculated the initial capital cost of fixtures per photon delivered and determined that LED fixtures cost five to ten times more than HPS fixtures. The five-year electric plus fixture cost per mole of photons is thus 2.3 times higher for LED fixtures, due to high capital costs. Compared to electric costs, our analysis indicates that the long-term maintenance costs are small for both technologies. If widely spaced benches are a necessary part of a production system, the unique ability of LED fixtures to efficiently focus photons on specific areas can be used to improve the photon capture by plant canopies. Our analysis demonstrates, however, that the cost per photon delivered is higher in these systems, regardless of fixture category. The lowest lighting system costs are realized when an efficient fixture is coupled with effective canopy photon capture. PMID:24905835

  9. Vortex shedding by a Savonius rotor

    NASA Astrophysics Data System (ADS)

    Botrini, M.; Beguier, C.; Chauvin, A.; Brun, R.

    1984-05-01

    A series of flow visualizations was performed to characterize the wake vortices of a Savonius rotor. The trials were undertaken in an attempt to account for discrepancies between theoretical and experimentally-derived power coefficients. The Savonius examined was two-bladed with a center offset. All tests were made in a water tunnel. Dye injection provided the visualization, and average velocities and velocity fluctuations were measured using a laser Doppler anemometer. A system of three vortices was found to be periodically shed by the rotor. Flow velocity fluctuation intensity peaked as a vortex was shed. The vortex shedding alternated from blade to blade, so that one was shed from a blade moving upstream.

  10. Multi-wavelength analysis of Ellerman Bomb Light Curves

    NASA Astrophysics Data System (ADS)

    Herlender, M.; Berlicki, A.

    We present the results of a multi-wavelength photometric analysis of Ellerman Bomb (EB) observations obtained from the Dutch Open Telescope. In our data we have found 6 EBs located in the super-penumbra of the main spot in the active region NOAA 10781. We present light curves of EB observed in the Hα line centre and wing +0.7 Å, in the Ca II H line centre and wing~+2.35 Å, in the G-band and in the TRACE 1600 Å filter. We have shown that EBs were visible in the G-band and moreover, there was a good correlation between the light curves in the G-band and in the Hα line wings. We also found quasi-periodic oscillations of EBs brightness in the G-band, CaII H line and TRACE 1600 Å filter.