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Sample records for apocarotenoids shedding light

  1. 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

  2. RNA interference-mediated repression of MtCCD1 in mycorrhizal roots of Medicago truncatula causes accumulation of C27 apocarotenoids, shedding light on the functional role of CCD1.

    PubMed

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

    2008-11-01

    Tailoring carotenoids by plant carotenoid cleavage dioxygenases (CCDs) generates various bioactive apocarotenoids. Recombinant CCD1 has been shown to catalyze symmetrical cleavage of C(40) 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 (C(13) cyclohexenone and C(14) 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 C(27) 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 C(27) apocarotenoids as the major substrates of CCD1 in mycorrhizal root cells. Moreover, literature data implicate C(27) 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 (C(27)-->C(14)+C(13)), while the first step (C(40)-->C(27)+C(13)) may be catalyzed by CCD7 and/or CCD4 inside plastids.

  3. 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)

  4. 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)

  5. 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

  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 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)

  8. 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…

  9. 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)

  10. 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…

  11. Shedding light on night myopia.

    PubMed

    López-Gil, Norberto; Peixoto-de-Matos, Sofia C; Thibos, Larry N; González-Méijome, José Manuel

    2012-01-01

    First described during the 18th century, the cause of night myopia remains a controversial topic. Whereas several explanations have been suggested in the literature, particularly related with accommodation or chromatic shift in scotopic light conditions, no definitive explanation for its aetiology has been provided. We describe an experiment in which ocular refractive state was objectively and subjectively measured while viewing two kind of stimulus: letters on a bright background and a punctual source of light in a dark background. We found that under photopic conditions the optimum refractive state of the accommodating eye is significantly more myopic when maximizing perceived quality of a point source on a dark background compared to a conventional letter chart with black letters on a white background. Optical modeling suggested this difference in refractive state is due to spherical aberration. Since isolated point sources are more likely encountered at night, whereas extended objects are more likely encountered in the daytime, our results suggest that a significant part of the night myopia phenomenon is determined by the nature of the visual stimulus and the visual task used to assess ocular refractive state.

  12. Shedding Light on and with Example Spaces

    ERIC Educational Resources Information Center

    Goldenberg, Paul; Mason, John

    2008-01-01

    Building on the papers in this special issue as well as on our own experience and research, we try to shed light on the construct of "example spaces" and on how it can inform research and practice in the teaching and learning of mathematical concepts. Consistent with our way of working, we delay definition until after appropriate reader experience…

  13. Shedding Light on Dark Matter at Colliders

    NASA Astrophysics Data System (ADS)

    Mitsou, Vasiliki A.

    2013-12-01

    Dark matter remains one of the most puzzling mysteries in Fundamental Physics of our times. Experiments at high-energy physics colliders are expected to shed light to its nature and determine its properties. This review focuses on recent searches for dark matter signatures at the Large Hadron Collider, also discussing related prospects in future e+e- colliders.

  14. 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

  15. Shedding new light on genetic dark matter

    PubMed Central

    2010-01-01

    Discoveries from genome-wide association studies have contributed to our knowledge of the genetic etiology of many complex diseases. However, these account for only a small fraction of each disease's heritability. Here, we comment on approaches currently available to uncover more of the genetic 'dark matter,' including an approach introduced recently by Naukkarinen and colleagues. These authors propose a method for distinguishing between gene expression driven by genetic variation and that driven by non-genetic factors. This dichotomy allows investigators to focus statistical tests and further molecular analyses on a smaller set of genes, thereby discovering new genetic variation affecting risk for disease. We need more methods like this one if we are to shed a powerful light on dark matter. By enhancing our understanding of molecular genetic etiology, such methods will help us to understand disease processes better and will advance the promise of personalized medicine. PMID:21067556

  16. 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.

  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. 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

  19. 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

  20. 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

  1. 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

  2. Study Sheds Light on Safety of Driving with Epilepsy

    MedlinePlus

    ... Study Sheds Light on Safety of Driving With Epilepsy Those who had longer seizures during driving tests ... SUNDAY, Dec. 4, 2016 (HealthDay News) -- People with epilepsy who experienced longer seizures during a simulated driving ...

  3. Nanocrystals: Shedding new light on silicon

    NASA Astrophysics Data System (ADS)

    Gösele, Ulrich

    2008-03-01

    Experiments in magnetic fields suggest that defects are responsible for light emission from silicon nanocrystals. However, when these defects are passivated with hydrogen, quantum effects become responsible for the emission.

  4. 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)

  5. 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)

  6. Shedding new light on composite polymerization.

    PubMed

    Caughman, W Frank; Rueggeberg, F A

    2002-01-01

    Life usually gets simpler, but in the case of photocuring dental restorative materials, just the opposite is true. Confusing and contradictory barrages of clinical claims have been made with the ever-growing variety of light-curing sources available today. Often, laboratory research or clinical studies related to these systems are lacking prior to their being introduced to the market, leaving the clinician to become the "testing ground." Manufacturers prefer to market the newest technology available, yet, depending on the type of practice and composite system in use, such "state-of-the-art" devices may offer no advantage. For some clinicians, changing to a "fast cure" composite in combination with a traditional QTH light, instead of purchasing a $4,000 PAC light, may be the only improvement in efficiency needed. However, others may want to spend as little time as possible per procedure and do not mind investing in the newest, yet "unproven" technology. Either way, today's clinician needs to be wary of the many claims made by manufacturers of all light-curing units. It is prudent that the clinician, prior to selecting a device, aggressively ask questions and dig for the truth before "buying into" a particular unit or system philosophy. At stake are the durability of restorations, the satisfaction of patient and the well-earned reputation of the operator.

  7. 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

  8. 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.

  9. 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

  10. Shedding new light on opsin evolution

    PubMed Central

    Porter, Megan L.; Blasic, Joseph R.; Bok, Michael J.; Cameron, Evan G.; Pringle, Thomas; Cronin, Thomas W.; Robinson, Phyllis R.

    2012-01-01

    Opsin proteins are essential molecules in mediating the ability of animals to detect and use light for diverse biological functions. Therefore, understanding the evolutionary history of opsins is key to understanding the evolution of light detection and photoreception in animals. As genomic data have appeared and rapidly expanded in quantity, it has become possible to analyse opsins that functionally and histologically are less well characterized, and thus to examine opsin evolution strictly from a genetic perspective. We have incorporated these new data into a large-scale, genome-based analysis of opsin evolution. We use an extensive phylogeny of currently known opsin sequence diversity as a foundation for examining the evolutionary distributions of key functional features within the opsin clade. This new analysis illustrates the lability of opsin protein-expression patterns, site-specific functionality (i.e. counterion position) and G-protein binding interactions. Further, it demonstrates the limitations of current model organisms, and highlights the need for further characterization of many of the opsin sequence groups with unknown function. PMID:22012981

  11. Shedding light on daytime flux partitioning

    NASA Astrophysics Data System (ADS)

    Wohlfahrt, Georg

    2017-04-01

    Flux partitioning, that is disaggregating the measured net ecosystem carbon dioxide exchange into the underlying gross primary productivity (GPP) and ecosystem respiration (ER), has become a key component of the FLUXNET processing chain and the resulting products are widely used by experimentalists and modellers alike. Here I review flux partitioning based on light response curve modelling, commonly termed the daytime flux partitioning approach. In particular I tackle the question whether daytime flux partitioning is able to account for the reduction in daytime ER relative to nighttime due to the reduction in leaf mitochondrial respiration in the presence of daylight. To this end I use synthetic data (with realistic noise superimposed) generated (i) by light response curve models upon which a daytime reduction in ER was imposed, (ii) results from a process-oriented soil-vegetation-atmosphere-transfer model, as well as (iii) experimental data from a simple ecosystem, where daytime ER was estimated based on a combination of complementary measurements and a canopy model.

  12. Shedding new light on opsin evolution.

    PubMed

    Porter, Megan L; Blasic, Joseph R; Bok, Michael J; Cameron, Evan G; Pringle, Thomas; Cronin, Thomas W; Robinson, Phyllis R

    2012-01-07

    Opsin proteins are essential molecules in mediating the ability of animals to detect and use light for diverse biological functions. Therefore, understanding the evolutionary history of opsins is key to understanding the evolution of light detection and photoreception in animals. As genomic data have appeared and rapidly expanded in quantity, it has become possible to analyse opsins that functionally and histologically are less well characterized, and thus to examine opsin evolution strictly from a genetic perspective. We have incorporated these new data into a large-scale, genome-based analysis of opsin evolution. We use an extensive phylogeny of currently known opsin sequence diversity as a foundation for examining the evolutionary distributions of key functional features within the opsin clade. This new analysis illustrates the lability of opsin protein-expression patterns, site-specific functionality (i.e. counterion position) and G-protein binding interactions. Further, it demonstrates the limitations of current model organisms, and highlights the need for further characterization of many of the opsin sequence groups with unknown function.

  13. 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.

  14. 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.

  15. Shedding new light on viral photosynthesis.

    PubMed

    Puxty, Richard J; Millard, Andrew D; Evans, David J; Scanlan, David J

    2015-10-01

    Viruses infecting the environmentally important marine cyanobacteria Prochlorococcus and Synechococcus encode 'auxiliary metabolic genes' (AMGs) involved in the light and dark reactions of photosynthesis. Here, we discuss progress on the inventory of such AMGs in the ever-increasing number of viral genome sequences as well as in metagenomic datasets. We contextualise these gene acquisitions with reference to a hypothesised fitness gain to the phage. We also report new evidence with regard to the sequence and predicted structural properties of viral petE genes encoding the soluble electron carrier plastocyanin. Viral copies of PetE exhibit extensive modifications to the N-terminal signal peptide and possess several novel residues in a region responsible for interaction with redox partners. We also highlight potential knowledge gaps in this field and discuss future opportunities to discover novel phage-host interactions involved in the photosynthetic process.

  16. Shedding new light on retinal protein photochemistry.

    PubMed

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

    2013-01-01

    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.

  17. 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

  18. Shedding light on biology of bacterial cells

    PubMed Central

    2016-01-01

    To understand basic principles of living organisms one has to know many different properties of all cellular components, their mutual interactions but also their amounts and spatial organization. Live-cell imaging is one possible approach to obtain such data. To get multiple snapshots of a cellular process, the imaging approach has to be gentle enough to not disrupt basic functions of the cell but also have high temporal and spatial resolution to detect and describe the changes. Light microscopy has become a method of choice and since its early development over 300 years ago revolutionized our understanding of living organisms. As most cellular components are indistinguishable from the rest of the cellular contents, the second revolution came from a discovery of specific labelling techniques, such as fusions to fluorescent proteins that allowed specific tracking of a component of interest. Currently, several different tags can be tracked independently and this allows us to simultaneously monitor the dynamics of several cellular components and from the correlation of their dynamics to infer their respective functions. It is, therefore, not surprising that live-cell fluorescence microscopy significantly advanced our understanding of basic cellular processes. Current cameras are fast enough to detect changes with millisecond time resolution and are sensitive enough to detect even a few photons per pixel. Together with constant improvement of properties of fluorescent tags, it is now possible to track single molecules in living cells over an extended period of time with a great temporal resolution. The parallel development of new illumination and detection techniques allowed breaking the diffraction barrier and thus further pushed the resolution limit of light microscopy. In this review, we would like to cover recent advances in live-cell imaging technology relevant to bacterial cells and provide a few examples of research that has been possible due to imaging. This

  19. Shedding light on biology of bacterial cells.

    PubMed

    Schneider, Johannes P; Basler, Marek

    2016-11-05

    To understand basic principles of living organisms one has to know many different properties of all cellular components, their mutual interactions but also their amounts and spatial organization. Live-cell imaging is one possible approach to obtain such data. To get multiple snapshots of a cellular process, the imaging approach has to be gentle enough to not disrupt basic functions of the cell but also have high temporal and spatial resolution to detect and describe the changes. Light microscopy has become a method of choice and since its early development over 300 years ago revolutionized our understanding of living organisms. As most cellular components are indistinguishable from the rest of the cellular contents, the second revolution came from a discovery of specific labelling techniques, such as fusions to fluorescent proteins that allowed specific tracking of a component of interest. Currently, several different tags can be tracked independently and this allows us to simultaneously monitor the dynamics of several cellular components and from the correlation of their dynamics to infer their respective functions. It is, therefore, not surprising that live-cell fluorescence microscopy significantly advanced our understanding of basic cellular processes. Current cameras are fast enough to detect changes with millisecond time resolution and are sensitive enough to detect even a few photons per pixel. Together with constant improvement of properties of fluorescent tags, it is now possible to track single molecules in living cells over an extended period of time with a great temporal resolution. The parallel development of new illumination and detection techniques allowed breaking the diffraction barrier and thus further pushed the resolution limit of light microscopy. In this review, we would like to cover recent advances in live-cell imaging technology relevant to bacterial cells and provide a few examples of research that has been possible due to imaging

  20. 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

  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. CFTR Modulators: Shedding Light on Precision Medicine for Cystic Fibrosis

    PubMed Central

    Lopes-Pacheco, Miquéias

    2016-01-01

    Cystic fibrosis (CF) is the most common life-threatening monogenic disease afflicting Caucasian people. It affects the respiratory, gastrointestinal, glandular and reproductive systems. The major cause of morbidity and mortality in CF is the respiratory disorder caused by a vicious cycle of obstruction of the airways, inflammation and infection that leads to epithelial damage, tissue remodeling and end-stage lung disease. Over the past decades, life expectancy of CF patients has increased due to early diagnosis and improved treatments; however, these patients still present limited quality of life. Many attempts have been made to rescue CF transmembrane conductance regulator (CFTR) expression, function and stability, thereby overcoming the molecular basis of CF. Gene and protein variances caused by CFTR mutants lead to different CF phenotypes, which then require different treatments to quell the patients’ debilitating symptoms. In order to seek better approaches to treat CF patients and maximize therapeutic effects, CFTR mutants have been stratified into six groups (although several of these mutations present pleiotropic defects). The research with CFTR modulators (read-through agents, correctors, potentiators, stabilizers and amplifiers) has achieved remarkable progress, and these drugs are translating into pharmaceuticals and personalized treatments for CF patients. This review summarizes the main molecular and clinical features of CF, emphasizes the latest clinical trials using CFTR modulators, sheds light on the molecular mechanisms underlying these new and emerging treatments, and discusses the major breakthroughs and challenges to treating all CF patients. PMID:27656143

  5. 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.

  6. Shedding light on photosensitive behaviour in brown planaria (Dugesia Tigrina).

    PubMed

    Davidson, Colin; Prados, Jose; Gibson, Claire L; Young, Andrew M J; Barnes, Darrel; Sherlock, Rachel; Hutchinson, Claire V

    2011-01-01

    The planarian flatworm is one of the simplest animals to develop two eyecups that enable them to detect the presence and direction of light, which they typically avoid. In this study we assessed responses of planaria to different intensities of light. We found that they exhibited a graded, sigmoidal, photonegative response to light intensity. A two-octave increase in luminance (on the upward slope of the sigmoid) corresponded to a 9% increase in the speed planaria travelled to avoid light.

  7. Shedding light on diatom photonics by means of digital holography.

    PubMed

    Di Caprio, Giuseppe; Coppola, Giuseppe; De Stefano, Luca; De Stefano, Mario; Antonucci, Alessandra; Congestri, Roberta; De Tommasi, Edoardo

    2014-05-01

    Diatoms are among the dominant phytoplankters in the world's oceans, and their external silica investments, resembling artificial photonic crystals, are expected to play an active role in light manipulation. Digital holography allowed studying the interaction with light of Coscinodiscus wailesii cell wall reconstructing the light confinement inside the cell cytoplasm, condition that is hardly accessible via standard microscopy. The full characterization of the propagated beam, in terms of quantitative phase and intensity, removed a long-standing ambiguity about the origin of the light confinement. The data were discussed in the light of living cell behavior in response to their environment.

  8. Perovskite solar cells: Shedding light on film crystallization

    NASA Astrophysics Data System (ADS)

    Bakr, Osman M.; Mohammed, Omar F.

    2017-06-01

    A study on the formation of methylammonium lead iodide perovskite films reveals that light illumination influences the crystallization kinetics, therefore affecting the final photovoltaic performance of these materials.

  9. Microparticles: new light shed on the understanding of venous thromboembolism

    PubMed Central

    Zhou, Lin; Qi, Xiao-long; Xu, Ming-xin; Mao, Yu; Liu, Ming-lin; Song, Hao-ming

    2014-01-01

    Microparticles are small membrane fragments shed primarily from blood and endothelial cells during either activation or apoptosis. There is mounting evidence suggesting that microparticles perform a large array of biological functions and contribute to various diseases. Of these disease processes, a significant link has been established between microparticles and venous thromboembolism. Advances in research on the role of microparticles in thrombosis have yielded crucial insights into possible mechanisms, diagnoses and therapeutic targets of venous thromboembolism. In this review, we discuss the definition and properties of microparticles and venous thromboembolism, provide a synopsis of the evidence detailing the contributions of microparticles to venous thromboembolism, and propose potential mechanisms, by which venous thromboembolism occurs. Moreover, we illustrate a possible role of microparticles in cancer-related venous thromboembolism. PMID:25152025

  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. 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)

  12. Shedding light on ethylene metabolism in higher plants

    PubMed Central

    Rodrigues, Maria A.; Bianchetti, Ricardo E.; Freschi, Luciano

    2014-01-01

    Ethylene metabolism in higher plants is regulated by a wide array of endogenous and environmental factors. During most physiological processes, ethylene levels are mainly determined by a strict control of the rate-limiting biosynthetic steps responsible for the production of 1-aminocyclopropane-1-carboxylic acid (ACC) and its subsequent conversion to ethylene. Responsible for these reactions, the key enzymes ACC synthase and ACC oxidase are encoded by multigene families formed by members that can be differentially regulated at the transcription and post-translational levels by specific developmental and environmental signals. Among the wide variety of environmental cues controlling plant ethylene production, light quality, duration, and intensity have consistently been demonstrated to influence the metabolism of this plant hormone in diverse plant tissues, organs, and species. Although still not completely elucidated, the mechanisms underlying the interaction between light signal transduction and ethylene evolution appears to involve a complex network that includes central transcription factors connecting multiple signaling pathways, which can be reciprocally modulated by ethylene itself, other phytohormones, and specific light wavelengths. Accumulating evidence has indicated particular photoreceptors as essential mediators in light-induced signaling cascades affecting ethylene levels. Therefore, this review specifically focuses on discussing the current knowledge of the potential molecular mechanisms implicated in the light-induced responses affecting ethylene metabolism during the regulation of developmental and metabolic plant responses. Besides presenting the state of the art in this research field, some overlooked mechanisms and future directions to elucidate the exact nature of the light–ethylene interplay in higher plants will also be compiled and discussed. PMID:25520728

  13. Shedding light on bioluminescence regulation in Vibrio fischeri.

    PubMed

    Miyashiro, Tim; Ruby, Edward G

    2012-06-01

    The bioluminescence emitted by the marine bacterium Vibrio fischeri is a particularly striking result of individual microbial cells co-ordinating a group behaviour. The genes responsible for light production are principally regulated by the LuxR-LuxI quorum-sensing system. In addition to LuxR-LuxI, numerous other genetic elements and environmental conditions control bioluminescence production. Efforts to mathematically model the LuxR-LuxI system are providing insight into the dynamics of this autoinduction behaviour. The Hawaiian squid Euprymna scolopes forms a natural symbiosis with V. fischeri, and utilizes the symbiont-derived bioluminescence for certain nocturnal behaviours, such as counterillumination. Recent work suggests that the tissue with which V. fischeri associates not only can detect bioluminescence but may also use this light to monitor the V. fischeri population. © 2012 Blackwell Publishing Ltd.

  14. 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.

  15. Metaphors in qualitative research: shedding light or casting shadows?

    PubMed

    Carpenter, Jacque

    2008-06-01

    The use of metaphors in qualitative research provides an opportunity to examine phenomena from a unique and creative perspective. Metaphors can be used to provide structure to the data; to understand a familiar process in a new light; to identify situation-specific interventions; and to evoke emotion. Misuse of metaphors may detract from the intended research message. Mixing metaphors, failing to follow through with metaphors, and using metaphors that do not fit the data can misrepresent the data. The choice to use metaphors should not become a self-serving attempt at creativity that supersedes subject and substance. At their best, metaphors illuminate the meanings of experiences; at their worst, metaphors distort or obscure the essences of them.

  16. 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.

  17. Shedding light on neutrino masses with dark forces

    DOE PAGES

    Batell, Brian; Pospelov, Maxim; Shuve, Brian

    2016-08-08

    Heavy right-handed neutrinos, N , provide the simplest explanation for the origin of light neutrino masses and mixings. If MN 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 darkmore » 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 + VB–L → X + N N ), the sensitivity reach is controlled by the square of the B – L gauge coupling. Here, 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.« less

  18. 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.

  19. 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.

  20. Aquaporins and leaf hydraulics: poplar sheds new light.

    PubMed

    Lopez, David; Venisse, Jean-Stéphane; Fumanal, Boris; Chaumont, François; Guillot, Esther; Daniels, Mark J; Cochard, Hervé; Julien, Jean-Louis; Gousset-Dupont, Aurélie

    2013-12-01

    To help understand leaf hydraulic conductance (Kleaf) modulation under high irradiance, well-watered poplars (Populus trichocarpa Torr. & Gray ex Hook and Populus nigra L.) were studied diurnally at molecular and ecophysiological scales. Transcriptional and translational modulations of plasma membrane intrinsic protein (PIP) aquaporins were evaluated in leaf samples during diurnal time courses. Among the 15 poplar PIP genes, a subset of two PIP1s and seven PIP2s are precociously induced within the first hour of the photoperiod concomitantly with a Kleaf increase. Since expression patterns were cyclic and reproducible over several days, we hypothesized that endogenous signals could be involved in PIP transcriptional regulation. To address this question, plants were submitted to forced darkness during their subjective photoperiod and compared with their control counterparts, which showed that some PIP1s and PIP2s have circadian regulation while others did not. Promoter analysis revealed that a large number of hormone, light, stress response and circadian elements are present. Finally, involvement of aquaporins is supported by the reduction of Kleaf by HgCl2 treatment.

  1. 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

  2. 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.

  3. Shedding light on neutrino masses with dark forces

    SciTech Connect

    Batell, Brian; Pospelov, Maxim; Shuve, Brian

    2016-08-08

    Heavy right-handed neutrinos, N , provide the simplest explanation for the origin of light neutrino masses and mixings. If MN 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 + VB–L → X + N N ), the sensitivity reach is controlled by the square of the B – L gauge coupling. Here, 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.

  4. Shedding Synchrotron Light on a Puzzle of Glasses

    ScienceCinema

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

    2016-07-12

    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.

  5. Shedding Synchrotron Light on a Puzzle of Glasses

    SciTech Connect

    Chumakov, Aleksandr

    2007-12-05

    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.

  6. Optical-fiber vortex-shedding flowmeter based on white-light interference

    NASA Astrophysics Data System (ADS)

    Zhao, Dong; Wu, Hongyan; Jia, Bo; Zhi, Ya'nan

    2009-08-01

    Optical-fiber vortex-shedding flowmeter is prospective in its application in the measurement field not only for the merits up from vortex-shedding flowmeter but also those in optical fiber sensor such as flexibility, strong endurance, anti electromagnetic interference capacity and adaptation in the flammable explosive environment. A new optical-fiber vortex-shedding flowmeter based on white-light interference principle is introduced in this paper. Because of only responding on dynamic disturbance, the all-fiber white-light interferometric flowmeter not only holds the high-sensitivity of interferometric sensors, but also overcomes the instability of the traditional interferometric sensors, which tend to being affected from the external environmental condition such as temperature fluctuation. At last, some experimental curves are presented in this paper.

  7. Shedding light on light: benefits of anthropogenic illumination to a nocturnally foraging shorebird.

    PubMed

    Dwyer, Ross G; Bearhop, Stuart; Campbell, Hamish A; Bryant, David M

    2013-03-01

    Intertidal habitats provide important feeding areas for migratory shorebirds. Anthropogenic developments along coasts can increase ambient light levels at night across adjacent inter-tidal zones. Here, we report the effects of elevated nocturnal light levels upon the foraging strategy of a migratory shorebird (common redshank Tringa totanus) overwintering on an industrialised estuary in Northern Europe. To monitor behaviour across the full intertidal area, individuals were located by day and night using VHF transmitters, and foraging behaviour was inferred from inbuilt posture sensors. Natural light was scored using moon-phase and cloud cover information and nocturnal artificial light levels were obtained using geo-referenced DMSP/OLS night-time satellite imagery at a 1-km resolution. Under high illumination levels, the commonest and apparently preferred foraging behaviour was sight-based. Conversely, birds feeding in areas with low levels of artificial light had an elevated foraging time and fed by touch, but switched to visual rather than tactile foraging behaviour on bright moonlit nights in the absence of cloud cover. Individuals occupying areas which were illuminated continuously by lighting from a large petrochemical complex invariably exhibited a visually based foraging behaviour independently of lunar phase and cloud cover. We show that ambient light levels affect the timing and distribution of foraging opportunities for redshank. We argue that light emitted from an industrial complex improved nocturnal visibility. This allowed sight-based foraging in place of tactile foraging, implying both a preference for sight-feeding and enhanced night-time foraging opportunities under these conditions. The study highlights the value of integrating remotely sensed data and telemetry techniques to assess the effect of anthropogenic change upon nocturnal behaviour and habitat use. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

  8. Using ordered carbon nanomaterials for shedding light on the mechanism of the cathodic oxygen reduction reaction.

    PubMed

    Ruvinskiy, Pavel S; Bonnefont, Antoine; Pham-Huu, Cuong; Savinova, Elena R

    2011-07-19

    Insufficient understanding of the mechanism of the cathodic oxygen reduction reaction puts constraints on the improvement of the efficiency of polymer electrolyte fuel cells (PEMFCs). We apply ordered catalytic layers based on vertically aligned carbon nanofilaments and combine experimental rotating ring-disk studies with mathematical modeling for shedding light on the mechanism of the oxygen reduction reaction on Pt nanoparticles. Based on the experimental and simulation evidence we propose a dual path ORR mechanism which comprises a "direct 4e(-)" and a "series 2e(-) + 2e(-)" pathway and explains switching between the two. For the first time we show that below 0.8 V the "direct" path may be discarded and the ORR predominantly occurs via H(2)O(2) mediated pathway, while in the potential interval between ca. 0.8 V and the onset of the ORR the "direct" path is dominating.

  9. Recent technological developments in proteomics shed new light on translational research on diabetic microangiopathy.

    PubMed

    Ma, Yuhang; Yang, Cheng; Tao, Yimin; Zhou, Hu; Wang, Yufan

    2013-11-01

    Diabetic microangiopathy has become a heavy social burden worldwide, but at present it is still difficult to predict and diagnose this ailment at an early stage. Various proteomics approaches have been applied to the pathophysiological study of diabetic microangiopathy. Conventional proteomics methods, including gel-based methods, exhibit limited sensitivity and robustness and have typically been used in high- or middle-abundance biomarker discovery. Clinical samples from patients with diabetic microangiopathy, such as biopsy samples, are minute in size. Therefore sample preparation, quantitative labelling and mass spectrometry technologies need to be optimized for low-abundance protein detection, multiple-sample processing and precision quantitation. In this review, we briefly introduce the recent technological developments in proteomics methods and summarize current proteomics-based, translational research on diabetic microangiopathy. Recent technological developments in proteomics tools may shed new light on the pathogenesis of diabetic microangiopathy and biomarkers and therapeutic targets related to this condition.

  10. Unusual modes of reproduction in social insects: shedding light on the evolutionary paradox of sex.

    PubMed

    Wenseleers, Tom; Van Oystaeyen, Annette

    2011-12-01

    The study of alternative genetic systems and mixed modes of reproduction, whereby sexual and asexual reproduction is combined within the same lifecycle, is of fundamental importance as they may shed light on classical evolutionary issues, such as the paradox of sex. Recently, several such cases were discovered in social insects. A closer examination of these systems has revealed many amazing facts, including the mixed use of asexual and sexual reproduction for the production of new queens and workers, males that can clone themselves and the routine use of incest without deleterious genetic consequences. In addition, in several species, remarkable cases of asexually reproducing socially parasitic worker lineages have been discovered. The study of these unusual systems promises to provide insight into many basic evolutionary questions, including the maintenance of sex, the expression of sexual conflict and kin conflict and the evolution of cheating in asexual lineages.

  11. Shedding light on the dark side of identity: Introduction to the special issue.

    PubMed

    Crocetti, Elisabetta; Beyers, Wim; Çok, Figen

    2016-02-01

    The aim of this special issue is to shed light in the dark side of identity formation in adolescence and emerging adulthood, that is, to provide some understanding in what exactly can go wrong in identity development. After summarizing the recent developments in identity development literature, in this introduction the main findings of all thirteen empirical papers are summarized into three overarching themes: (1) lack of identity integration as a risk factor, (2) reconsideration of commitment as a sign of identity uncertainty, and (3) ruminative exploration as another risk factor undermining healthy identity development. Finally, given that all papers in this special issue are based on conference presentations at the 14th Biennial Conference of the European Association for Research on Adolescence (EARA), some more information on that conference is included in this introduction.

  12. 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

  13. In Vivo Imaging Sheds Light on Immune Cell Migration and Function in Cancer

    PubMed Central

    Torcellan, Tommaso; Stolp, Jessica; Chtanova, Tatyana

    2017-01-01

    There is ample evidence for both beneficial and harmful involvement of the immune system in tumor development and spread. Immune cell recruitment to tumors is essential not only for the success of anticancer immune therapies but also for tumor-induced immune suppression. Now that immune-based therapies are playing an increasingly important role in treatment of solid tumors such as metastatic melanomas, precise analysis of the in vivo contributions of different leukocyte subsets in tumor immunity has become an even greater priority. Recently, this goal has been markedly facilitated by the use of intravital microscopy, which has enabled us to visualize the dynamic interactions between cells of the immune system and tumor targets in the context of the tumor microenvironment. For example, intravital imaging techniques have shed new light on T cell infiltration of tumors, the mechanisms of cancer cell killing, and how myeloid cells contribute to tumor tolerance and spread. This mini-review summarizes the recent advances made to our understanding of the roles of innate and adaptive immune cells in cancer based on the use of these in vivo imaging approaches. PMID:28382036

  14. In Vivo Imaging Sheds Light on Immune Cell Migration and Function in Cancer.

    PubMed

    Torcellan, Tommaso; Stolp, Jessica; Chtanova, Tatyana

    2017-01-01

    There is ample evidence for both beneficial and harmful involvement of the immune system in tumor development and spread. Immune cell recruitment to tumors is essential not only for the success of anticancer immune therapies but also for tumor-induced immune suppression. Now that immune-based therapies are playing an increasingly important role in treatment of solid tumors such as metastatic melanomas, precise analysis of the in vivo contributions of different leukocyte subsets in tumor immunity has become an even greater priority. Recently, this goal has been markedly facilitated by the use of intravital microscopy, which has enabled us to visualize the dynamic interactions between cells of the immune system and tumor targets in the context of the tumor microenvironment. For example, intravital imaging techniques have shed new light on T cell infiltration of tumors, the mechanisms of cancer cell killing, and how myeloid cells contribute to tumor tolerance and spread. This mini-review summarizes the recent advances made to our understanding of the roles of innate and adaptive immune cells in cancer based on the use of these in vivo imaging approaches.

  15. 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

    2015-11-02

    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.

  16. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. The oldest ionoscopiform from China sheds new light on the early evolution of halecomorph fishes.

    PubMed

    Xu, Guang-Hui; Zhao, Li-Jun; Coates, Michael I

    2014-05-01

    The Halecomorphi are a major subdivision of the ray-finned fishes. Although living halecomorphs are represented solely by the freshwater bowfin, Amia calva, this clade has a rich fossil history, and the resolution of interrelationships among extinct members is central to the problem of understanding the origin of the Teleostei, the largest clade of extant vertebrates. The Ionoscopiformes are extinct marine halecomorphs that were inferred to have originated in the Late Jurassic of Europe, and subsequently dispersed to the Early Cretaceous of the New World. Here, we report the discovery of a new ionoscopiform, Robustichthys luopingensis gen. et sp. nov., based on eight well-preserved specimens from the Anisian (242-247 Ma), Middle Triassic marine deposits of Luoping, eastern Yunnan Province, China. The new species documents the oldest known ionoscopiform, extending the stratigraphic range of this group by approximately 90 Ma, and the geographical distribution of this group into the Middle Triassic of South China, a part of eastern Palaeotethys Ocean. These new data provide a minimum estimate for the split of Ionoscopiformes from its sister clade Amiiformes and shed new light on the origin of ionoscopiform fishes.

  18. Fossils from the Middle Jurassic of China shed light on morphology of Choristopsychidae (Insecta, Mecoptera)

    PubMed Central

    Qiao, Xiao; Shih, Chung Kun; Petrulevičius, Julian F.; Dong, Ren

    2013-01-01

    Abstract Choristopsychidae, established by Martynov in 1937 with a single isolated forewing, is a little known extinct family in Mecoptera. Since then, no new members of this enigmatic family have been described. Based on 23 well-preserved specimens with complete body and wings from the Middle Jurassic of northeastern China, we report one new genus and three new species of Choristopsychidae, two new species of the genus Choristopsyche Martynov, 1937: Choristopsyche perfecta sp. n. and Choristopsyche asticta sp. n.; one new species of Paristopsyche gen. n.: Paristopsyche angelineae sp. n.; and re-describe Choristopsyche tenuinervis Martynov, 1937. In addition, we emend the diagnoses of Choristopsychidae and Choristopsyche. Analyzing the forewing length/width ratios of representative species in Mecoptera, we confirm that choristopsychids have the lowest ratio of forewing length/width, meaning broadest forewings. These findings, the first fossil choristopsychids with well-preserved body structure and the first record of Choristopsychidae in China, shed light on the morphology of these taxa and broaden their distribution from Tajikistan to China, while increasing the diversity of Mesozoic Mecoptera in China. PMID:23950679

  19. Hellbender genome sequences shed light on genomic expansion at the base of crown salamanders.

    PubMed

    Sun, Cheng; Mueller, Rachel Lockridge

    2014-07-01

    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.

  20. 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

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

    PubMed

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

    2016-06-27

    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.

  2. Ethical considerations in biobanks: how a public health ethics perspective sheds new light on old controversies.

    PubMed

    Virani, Alice Hawkins; Longstaff, Holly

    2015-06-01

    Biobanks, collections of biospecimens with or without linked medical data, have increased dramatically in number in the last two decades. Their potential power to identify the underlying mechanisms of both rare and common disease has catalyzed their proliferation in the academic, medical, and private sectors. Despite demonstrated public support of biobanks, some within the academic, governmental, and public realms have also expressed cautions associated with the ethical, legal, and social (ELSI) implications of biobanks. These issues include concerns related to the privacy and confidentiality of data; return of results and incidental findings to participants; data sharing and secondary use of samples; informed consent mechanisms; ownership of specimens; and benefit sharing (i.e., the distribution of financial or other assets that result from the research). Such apprehensions become amplified as more researchers seek to pursue national and cross-border collaborations between biobanks. This paper provides an overview of two of the most contentious topics in biobank literature - informed consent and return of individual research results or incidental findings - and explores how a public health ethics lens may help to shed new light on how these issues may be best approached and managed. Doing so also demonstrates the important role that genetic counselors can play in the ongoing discussion of ethically appropriate biobank recruitment and management strategies, as well as identifies important areas of ongoing empirical research on these unresolved topics.

  3. How counterfactuals of Red-Queen theory shed light on science and its historiography.

    PubMed

    Dagg, Joachim L

    2017-08-01

    A historical episode of evolutionary theory, which has lead to the Red Queen theory of the evolutionary maintenance of sex, includes two striking contingencies. These are used to explore alternative what-if scenarios, in order to test some common opinions about such counterfactuals. This sheds new light on the nature of science and its historiography. One counterfactual leads to an unexpected convergence of its result to that of the actual science but, nevertheless, differs in its causal structure. The other diverges towards an incompatible alternative, but this requires further contingent choices that also diverge from actual science. The convergence in the first counterfactual is due to a horizontal transfer of knowledge. Similar transfers of knowledge are typical for innovations of actual science. This suggests that contingent choices can merge as well as fork research traditions both in actual research and counterfactual history. Neither the paths of the actual history of science nor those of its counterfactual alternatives will form a tree of exclusively diverging bifurcations, but a network instead. Convergencies in counterfactuals may, therefore, be due to the web-structure of science as much as to the aims of the historians in question. Furthermore, the difference in causal structure between the actual science and its convergent counterfactual might become diagnostic for external factors rather than internal aims forcing a historian towards convergence. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Zebrafish models flex their muscles to shed light on muscular dystrophies.

    PubMed

    Berger, Joachim; Currie, Peter D

    2012-11-01

    Muscular dystrophies are a group of genetic disorders that specifically affect skeletal muscle and are characterized by progressive muscle degeneration and weakening. To develop therapies and treatments for these diseases, a better understanding of the molecular basis of muscular dystrophies is required. Thus, identification of causative genes mutated in specific disorders and the study of relevant animal models are imperative. Zebrafish genetic models of human muscle disorders often closely resemble disease pathogenesis, and the optical clarity of zebrafish embryos and larvae enables visualization of dynamic molecular processes in vivo. As an adjunct tool, morpholino studies provide insight into the molecular function of genes and allow rapid assessment of candidate genes for human muscular dystrophies. This unique set of attributes makes the zebrafish model system particularly valuable for the study of muscle diseases. This review discusses how recent research using zebrafish has shed light on the pathological basis of muscular dystrophies, with particular focus on the muscle cell membrane and the linkage between the myofibre cytoskeleton and the extracellular matrix.

  5. The oldest ionoscopiform from China sheds new light on the early evolution of halecomorph fishes

    PubMed Central

    Xu, Guang-Hui; Zhao, Li-Jun; Coates, Michael I.

    2014-01-01

    The Halecomorphi are a major subdivision of the ray-finned fishes. Although living halecomorphs are represented solely by the freshwater bowfin, Amia calva, this clade has a rich fossil history, and the resolution of interrelationships among extinct members is central to the problem of understanding the origin of the Teleostei, the largest clade of extant vertebrates. The Ionoscopiformes are extinct marine halecomorphs that were inferred to have originated in the Late Jurassic of Europe, and subsequently dispersed to the Early Cretaceous of the New World. Here, we report the discovery of a new ionoscopiform, Robustichthys luopingensis gen. et sp. nov., based on eight well-preserved specimens from the Anisian (242–247 Ma), Middle Triassic marine deposits of Luoping, eastern Yunnan Province, China. The new species documents the oldest known ionoscopiform, extending the stratigraphic range of this group by approximately 90 Ma, and the geographical distribution of this group into the Middle Triassic of South China, a part of eastern Palaeotethys Ocean. These new data provide a minimum estimate for the split of Ionoscopiformes from its sister clade Amiiformes and shed new light on the origin of ionoscopiform fishes. PMID:24872460

  6. 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.

  7. How Hox genes can shed light on the place of echinoderms among the deuterostomes

    PubMed Central

    2014-01-01

    Background The Hox gene cluster ranks among the greatest of biological discoveries of the past 30 years. Morphogenetic patterning genes are remarkable for the systems they regulate during major ontogenetic events, and for their expressions of molecular, temporal, and spatial colinearity. Recent descriptions of exceptions to these colinearities are suggesting deep phylogenetic signal that can be used to explore origins of entire deuterostome phyla. Among the most enigmatic of these deuterostomes in terms of unique body patterning are the echinoderms. However, there remains no overall synthesis of the correlation between this signal and the variations observable in the presence/absence and expression patterns of Hox genes. Results Recent data from Hox cluster analyses shed light on how the bizarre shift from bilateral larvae to radial adults during echinoderm ontogeny can be accomplished by equally radical modifications within the Hox cluster. In order to explore this more fully, a compilation of observations on the genetic patterns among deuterostomes is integrated with the body patterning trajectories seen across the deuterostome clade. Conclusions Synthesis of available data helps to explain morphogenesis along the anterior/posterior axis of echinoderms, delineating the origins and fate of that axis during ontogeny. From this, it is easy to distinguish between ‘seriality’ along echinoderm rays and true A/P axis phenomena such as colinearity within the somatocoels, and the ontogenetic outcomes of the unique translocation and inversion of the anterior Hox class found within the Echinodermata. An up-to-date summary and integration of the disparate lines of research so far produced on the relationship between Hox genes and pattern formation for all deuterostomes allows for development of a phylogeny and scenario for the evolution of deuterostomes in general, and the Echinodermata in particular. PMID:24959343

  8. Isolation of a series of apocarotenoids from the fruits of the red paprika Capsicum annuum L.

    PubMed

    Maoka, T; Fujiwara, Y; Hashimoto, K; Akimoto, N

    2001-03-01

    Eleven apocarotenoids (1-11) including five new compounds, 4, 6, 9, 10 and 11, were isolated from the fruits of the red paprika Capsicum annuum L. The structures of new apocarotenoids were determined to be apo-14'-zeaxanthinal (4), apo-13-zeaxanthinone (6), apo-12'-capsorubinal (9), apo-8'-capsorubinal (10), and 9,9'-diapo-10,9'-retro-carotene-9,9'-dione (11) by spectroscopic analysis. The other six known apocarotenoids were identified to be apo-8'-zeaxanthinal (1), apo-10'-zeaxanthinal (2), apo-12'-zeaxanthinal (3), apo-15-zeaxanthinal (5), apo-11-zeaxanthinal (7), and apo-9-zeaxanthinone (8) which have not been previously found in paprika. These apocarotenoids were assumed to be oxidative cleavage products of C(40) carotenoid such as capsanthin in paprika.

  9. Depression, Anxiety, and Stress Symptoms in Menopausal Arab Women: Shedding More Light on a Complex Relationship.

    PubMed

    Bener, A; Saleh, N M; Bakir, A; Bhugra, D

    2016-01-01

    The association between depression, anxiety, and stress among Arab menopause and postmenopausal women have been explored in detailed. The objective of this study was to determine the correlation between depression, anxiety, and stress in menopausal and postmenopausal women and shedding more light on a complex relationship. A cross-sectional descriptive study was used to generate menopause symptoms experienced by Arabian women at the primary health care centers in Qatar. A representative sample of 1468 women aged 45-65 years were approached during July 2012 and May 2014 and 1101 women agreed to participate (75.0%) and responded to the study. Depression, anxiety, and stress were measured using the Depression Anxiety Stress Scales 21. Data on body mass index (BMI), clinical and other parameters were used. Univariate, multivariate, and matrix correlation analysis were performed for statistical analysis. A total of 1101 women agreed to participate after informed consent was obtained. The mean age and standard deviation (SD) of the menopausal age were 49.55 (3.12), the mean and SD of postmenopausal age was 58.08 (3.26) (P < 0.001). There were statistically significant differences between menopausal stages with regards to age, ethnicity, educational status, occupation status, and place of living. Furthermore, there were statistically significant differences between menopausal stages with regards to BMI, systolic and diastolic blood pressure (BP), Vitamin D deficiency, and diseases. Depression and anxiety were more common among postmenopause women. Furthermore, there were no differences between the groups regarding the frequency of certain levels of stress among menopause and postmenopause. The multivariate regression analyses revealed that age in years, diastolic BP, consanguinity, regular exercise were a predictor for depression. Meanwhile, diastolic BP, occupation, and physical activity considered the main risk factors for anxiety. Furthermore, age in years, occupation

  10. 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

  11. German physicians "on strike"--shedding light on the roots of physician dissatisfaction.

    PubMed

    Janus, Katharina; Amelung, Volker Eric; Gaitanides, Michael; Schwartz, Friedrich Wilhelm

    2007-08-01

    , continuous education and job security, administrative tasks and collegial relationships were highly significant, specialized technology and patient contact were significant and research and teaching and international exchange were not significant in contributing to physician job satisfaction. This study sheds light to the underlying factors that contribute to physician job satisfaction in Germany, and it provides insights into the reasons for physicians leaving medical practice. In order for a health system to recruit and retain physicians, it may be necessary for a system's physician strategy to shift from focusing primarily on hard, monetary and compensation-related factors to a broader focus that incorporates the soft, non-monetary factors. The implementation of policies and management practices that reduce the time burden on physicians, and enhance physicians' participation in the development of patient care management processes and in managerial decisions that affect patient care appears to be crucial. The result will be increased job satisfaction among physicians, which is important to the future recruitment and retention of doctors, as well as to the productivity and quality of the services provided by this essential component of our medical care systems.

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

    PubMed

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

    2013-08-23

    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.

  13. Differential spatio-temporal expression of carotenoid cleavage dioxygenases regulates apocarotenoid fluxes during AM symbiosis.

    PubMed

    López-Ráez, Juan A; Fernández, Iván; García, Juan M; Berrio, Estefanía; Bonfante, Paola; Walter, Michael H; Pozo, María J

    2015-01-01

    Apocarotenoids are a class of compounds that play important roles in nature. In recent years, a prominent role for these compounds in arbuscular mycorrhizal (AM) symbiosis has been shown. They are derived from carotenoids by the action of the carotenoid cleavage dioxygenase (CCD) enzyme family. In the present study, using tomato as a model, the spatio-temporal expression pattern of the CCD genes during AM symbiosis establishment and functioning was investigated. In addition, the levels of the apocarotenoids strigolactones (SLs), C13 α-ionol and C14 mycorradicin (C13/C14) derivatives were analyzed. The results suggest an increase in SLs promoted by the presence of the AM fungus at the early stages of the interaction, which correlated with an induction of the SL biosynthesis gene SlCCD7. At later stages, induction of SlCCD7 and SlCCD1 expression in arbusculated cells promoted the production of C13/C14 apocarotenoid derivatives. We show here that the biosynthesis of apocarotenoids during AM symbiosis is finely regulated throughout the entire process at the gene expression level, and that CCD7 constitutes a key player in this regulation. Once the symbiosis is established, apocarotenoid flux would be turned towards the production of C13/C14 derivatives, thus reducing SL biosynthesis and maintaining a functional symbiosis.

  14. 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) ...

  15. 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) ...

  16. Chemical vs. biotechnological synthesis of C13-apocarotenoids: current methods, applications and perspectives.

    PubMed

    Cataldo, Vicente F; López, Javiera; Cárcamo, Martín; Agosin, Eduardo

    2016-07-01

    Apocarotenoids are natural compounds derived from the oxidative cleavage of carotenoids. Particularly, C13-apocarotenoids are volatile compounds that contribute to the aromas of different flowers and fruits and are highly valued by the Flavor and Fragrance industry. So far, the chemical synthesis of these terpenoids has dominated the industry. Nonetheless, the increasing consumer demand for more natural and sustainable processes raises an interesting opportunity for bio-production alternatives. In this regard, enzymatic biocatalysis and metabolically engineered microorganisms emerge as attractive biotechnological options. The present review summarizes promising bioengineering approaches with regard to chemical production methods for the synthesis of two families of C13-apocarotenoids: ionones/dihydroionones and damascones/damascenone. We discuss each method and its applicability, with a thorough comparative analysis for ionones, focusing on the production process, regulatory aspects, and sustainability.

  17. A novel carotenoid cleavage activity involved in the biosynthesis of Citrus fruit-specific apocarotenoid pigments

    PubMed Central

    Rodrigo, María J.; Alquézar, Berta; Al-Babili, Salim

    2013-01-01

    Citrus is the first tree crop in terms of fruit production. The colour of Citrus fruit is one of the main quality attributes, caused by the accumulation of carotenoids and their derivative C30 apocarotenoids, mainly β-citraurin (3-hydroxy-β-apo-8′-carotenal), which provide an attractive orange-reddish tint to the peel of oranges and mandarins. Though carotenoid biosynthesis and its regulation have been extensively studied in Citrus fruits, little is known about the formation of C30 apocarotenoids. The aim of this study was to the identify carotenoid cleavage enzyme(s) [CCD(s)] involved in the peel-specific C30 apocarotenoids. In silico data mining revealed a new family of five CCD4-type genes in Citrus. One gene of this family, CCD4b1, was expressed in reproductive and vegetative tissues of different Citrus species in a pattern correlating with the accumulation of C30 apocarotenoids. Moreover, developmental processes and treatments which alter Citrus fruit peel pigmentation led to changes of β-citraurin content and CCD4b1 transcript levels. These results point to the involvement of CCD4b1 in β-citraurin formation and indicate that the accumulation of this compound is determined by the availability of the presumed precursors zeaxanthin and β-cryptoxanthin. Functional analysis of CCD4b1 by in vitro assays unequivocally demonstrated the asymmetric cleavage activity at the 7′,8′ double bond in zeaxanthin and β-cryptoxanthin, confirming its role in C30 apocarotenoid biosynthesis. Thus, a novel plant carotenoid cleavage activity targeting the 7′,8′ double bond of cyclic C40 carotenoids has been identified. These results suggest that the presented enzyme is responsible for the biosynthesis of C30 apocarotenoids in Citrus which are key pigments in fruit coloration. PMID:24006419

  18. A novel carotenoid cleavage activity involved in the biosynthesis of Citrus fruit-specific apocarotenoid pigments.

    PubMed

    Rodrigo, María J; Alquézar, Berta; Alós, Enriqueta; Medina, Víctor; Carmona, Lourdes; Bruno, Mark; Al-Babili, Salim; Zacarías, Lorenzo

    2013-11-01

    Citrus is the first tree crop in terms of fruit production. The colour of Citrus fruit is one of the main quality attributes, caused by the accumulation of carotenoids and their derivative C30 apocarotenoids, mainly β-citraurin (3-hydroxy-β-apo-8'-carotenal), which provide an attractive orange-reddish tint to the peel of oranges and Mandarins. Though carotenoid biosynthesis and its regulation have been extensively studied in Citrus fruits, little is known about the formation of C30 apocarotenoids. The aim of this study was to the identify carotenoid cleavage enzyme(s) [CCD(s)] involved in the peel-specific C30 apocarotenoids. In silico data mining revealed a new family of five CCD4-type genes in Citrus. One gene of this family, CCD4b1, was expressed in reproductive and vegetative tissues of different Citrus species in a pattern correlating with the accumulation of C30 apocarotenoids. Moreover, developmental processes and treatments which alter Citrus fruit peel pigmentation led to changes of β-citraurin content and CCD4b1 transcript levels. These results point to the involvement of CCD4b1 in β-citraurin formation and indicate that the accumulation of this compound is determined by the availability of the presumed precursors zeaxanthin and β-cryptoxanthin. Functional analysis of CCD4b1 by in vitro assays unequivocally demonstrated the asymmetric cleavage activity at the 7',8' double bond in zeaxanthin and β-cryptoxanthin, confirming its role in C30 apocarotenoid biosynthesis. Thus, a novel plant carotenoid cleavage activity targeting the 7',8' double bond of cyclic C40 carotenoids has been identified. These results suggest that the presented enzyme is responsible for the biosynthesis of C30 apocarotenoids in Citrus which are key pigments in fruit coloration.

  19. 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.

  20. 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)

  1. 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)

  2. Shedding new light on viruses: super-resolution microscopy for studying human immunodeficiency virus.

    PubMed

    Müller, Barbara; Heilemann, Mike

    2013-10-01

    For more than 70 years electron microscopy (EM) techniques have played an important role in investigating structures of enveloped viruses. By contrast, use of fluorescence microscopy (FM) methods for this purpose was limited by the fact that the size of virus particles is generally around or below the diffraction limit of light microscopy. Various super-resolution (SR) fluorescence imaging techniques developed over the past two decades bypass the diffraction limit of light microscopy, allowing visualization of subviral details and bridging the gap between conventional FM and EM methods. We summarize here findings on human immunodeficiency virus (HIV-1) obtained using SR-FM techniques. Although the number of published studies is currently limited and some of the pioneering analyses also covered methodological or descriptive aspects, recent publications clearly indicate the potential to approach open questions in HIV-1 replication from a new angle.

  3. 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.

  4. Shedding (far-red) light on phytochrome mechanisms and responses in land plants.

    PubMed

    Possart, Anja; Fleck, Christian; Hiltbrunner, Andreas

    2014-03-01

    In order to monitor ambient light conditions, plants rely on functionally diversified photoreceptors. Among these, phytochromes perceive red (R) and far-red (FR) light. FR light does not constitute a photosynthetic energy source; it however influences adaptive and developmental processes. In seed plants, phytochrome A (phyA) acts as FR receptor and mediates FR high irradiance responses (FR-HIRs). It exerts a dual role by promoting e.g. germination and seedling de-etiolation in canopy shade and by antagonising shade avoidance growth. Even though cryptogam plants such as mosses and ferns do not have phyA, they show FR-induced responses. In the present review we discuss the mechanistic basis of phyA-dependent FR-HIRs as well as their dual role in seed plants. We compare FR responses in seed plants and cryptogam plants and conclude on different potential concepts for the detection of canopy shade. Scenarios for the evolution of FR perception and responses are discussed.

  5. Shedding light on auxin movement: light-regulation of polar auxin transport in the photocontrol of plant development.

    PubMed

    Sassi, Massimiliano; Wang, Juan; Ruberti, Ida; Vernoux, Teva; Xu, Jian

    2013-03-01

    By being sessile, plants have evolved a remarkable capacity to perceive and respond to changes in environmental conditions throughout their life cycle. Light represents probably the most important environmental factor that impinge on plant development because, other than supplying the energy source for photosynthesis, it also provides seasonal and positional information that are essential for the plant survival and fitness. Changes in the light environment can dramatically alter plant morphogenesis, especially during the early phases of plant life, and a compelling amount of evidence indicates that light-mediated changes in auxin homeostasis are central in these processes. Auxin exerts its morphogenetic action through instructive hormone gradients that drive developmental programs of plants. Such gradients are formed and maintained via an accurate control on directional auxin transport. This review summarizes the recent advances in understanding the influence of the light environment on polar auxin transport.

  6. Studies on cyanobacterial protein PipY shed light on structure, potential functions, and vitamin B6 -dependent epilepsy.

    PubMed

    Tremiño, Lorena; Forcada-Nadal, Alicia; Contreras, Asunción; Rubio, Vicente

    2017-09-15

    The Synechococcus elongatus COG0325 gene pipY functionally interacts with the nitrogen regulatory gene pipX. As a first step toward a molecular understanding of such interactions, we characterized PipY. This 221-residue protein is monomeric and hosts pyridoxal phosphate (PLP), binding it with limited affinity and losing it upon incubation with D-cycloserine. PipY crystal structures with and without PLP reveal a single-domain monomer folded as the TIM barrel of type-III fold PLP enzymes, with PLP highly exposed, fitting a role for PipY in PLP homeostasis. The mobile PLP phosphate-anchoring C-terminal helix might act as a trigger for PLP exchange. Exploiting the universality of COG0325 functions, we used PipY in site-directed mutagenesis studies to shed light on disease causation by epilepsy-associated mutations in the human COG0325 gene PROSC. © 2017 Federation of European Biochemical Societies.

  7. 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

  8. Retinal transcriptome sequencing sheds light on the adaptation to nocturnal and diurnal lifestyles in raptors

    PubMed Central

    Wu, Yonghua; Hadly, Elizabeth A.; Teng, Wenjia; Hao, Yuyang; Liang, Wei; Liu, Yu; Wang, Haitao

    2016-01-01

    Owls (Strigiformes) represent a fascinating group of birds that are the ecological night-time counterparts to diurnal raptors (Accipitriformes). The nocturnality of owls, unusual within birds, has favored an exceptional visual system that is highly tuned for hunting at night, yet the molecular basis for this adaptation is lacking. Here, using a comparative evolutionary analysis of 120 vision genes obtained by retinal transcriptome sequencing, we found strong positive selection for low-light vision genes in owls, which contributes to their remarkable nocturnal vision. Not surprisingly, we detected gene loss of the violet/ultraviolet-sensitive opsin (SWS1) in all owls we studied, but two other color vision genes, the red-sensitive LWS and the blue-sensitive SWS2, were found to be under strong positive selection, which may be linked to the spectral tunings of these genes toward maximizing photon absorption in crepuscular conditions. We also detected the only other positively selected genes associated with motion detection in falcons and positively selected genes associated with bright-light vision and eye protection in other diurnal raptors (Accipitriformes). Our results suggest the adaptive evolution of vision genes reflect differentiated activity time and distinct hunting behaviors. PMID:27645106

  9. Retinal transcriptome sequencing sheds light on the adaptation to nocturnal and diurnal lifestyles in raptors.

    PubMed

    Wu, Yonghua; Hadly, Elizabeth A; Teng, Wenjia; Hao, Yuyang; Liang, Wei; Liu, Yu; Wang, Haitao

    2016-09-20

    Owls (Strigiformes) represent a fascinating group of birds that are the ecological night-time counterparts to diurnal raptors (Accipitriformes). The nocturnality of owls, unusual within birds, has favored an exceptional visual system that is highly tuned for hunting at night, yet the molecular basis for this adaptation is lacking. Here, using a comparative evolutionary analysis of 120 vision genes obtained by retinal transcriptome sequencing, we found strong positive selection for low-light vision genes in owls, which contributes to their remarkable nocturnal vision. Not surprisingly, we detected gene loss of the violet/ultraviolet-sensitive opsin (SWS1) in all owls we studied, but two other color vision genes, the red-sensitive LWS and the blue-sensitive SWS2, were found to be under strong positive selection, which may be linked to the spectral tunings of these genes toward maximizing photon absorption in crepuscular conditions. We also detected the only other positively selected genes associated with motion detection in falcons and positively selected genes associated with bright-light vision and eye protection in other diurnal raptors (Accipitriformes). Our results suggest the adaptive evolution of vision genes reflect differentiated activity time and distinct hunting behaviors.

  10. Shedding light on a new treatment for diabetic wound healing: a review on phototherapy.

    PubMed

    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.

  11. 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

  12. [Xeroderma pigmentosum (XP) : A genetic disease sheds light on UV-induced skin cancer].

    PubMed

    Emmert, B; Hallier, E; Schön, M P; Emmert, S

    2011-02-01

    The recessively inherited nucleotide excision repair (NER) defect syndrome xeroderma pigmentosum (XP) serves as a model disease for UV-induced skin cancer. XP is characterized by sun-sensitivity, freckling, and poikilodermic skin changes in sun-exposed areas, and a more than 1000-fold increased risk of skin cancer including melanoma as well as basal and squamous cell carcinomas. Seven XP complementation groups (XP-A to XP-G) are known to date representing the defective genes in XP patients. An additional "variant" form (XPV) which is clinically indistinguishable from the complementation groups exhibits defective translesional synthesis. An enhanced understanding of skin cancer development in general can help to identify individuals at an increased risk who should take special precautions, for example to avoid occupational exposures. The position of skin cancer induced by UV-light as an occupational disease in the ordinance on industrial diseases (BKV) is currently a topic of research and discussion in Germany.

  13. Night-Break Experiments Shed Light on the Photoperiod1-Mediated Flowering1[OPEN

    PubMed Central

    Shaw, Lindsay M.; Cotter, Jennifer D.; Li, Chengxia

    2017-01-01

    Plants utilize variation in day length (photoperiod) to anticipate seasonal changes. They respond by modulating their growth and development to maximize seed production, which in cereal crops is directly related to yield. In wheat (Triticum aestivum), the acceleration of flowering under long days (LD) is dependent on the light induction of PHOTOPERIOD1 (PPD1) by phytochromes. Under LD, PPD1 activates FLOWERING LOCUS T1 (FT1), a mobile signaling protein that travels from the leaves to the shoot apical meristem to promote flowering. Here, we show that the interruption of long nights by short pulses of light (“night-break” [NB]) accelerates wheat flowering, suggesting that the duration of the night is critical for wheat photoperiodic response. PPD1 transcription was rapidly upregulated by NBs, and the magnitude of this induction increased with the length of darkness preceding the NB. Cycloheximide abolished the NB up-regulation of PPD1, suggesting that this process is dependent on active protein synthesis during darkness. While one NB was sufficient to induce PPD1, more than 15 NBs were required to induce high levels of FT1 expression and a strong acceleration of flowering. Multiple NBs did not affect the expression of core circadian clock genes. The acceleration of flowering by NB disappeared in ppd1-null mutants, demonstrating that this response is mediated by PPD1. The acceleration of flowering was strongest when NBs were applied in the middle of the night, suggesting that in addition to PPD1, other circadian-controlled factors are required for the up-regulation of FT1 expression and the acceleration of flowering. PMID:28408541

  14. Role of carotenoid cleavage dioxygenase 1 (CCD1) in apocarotenoid biogenesis revisited.

    PubMed

    Floss, Daniela S; Walter, Michael H

    2009-03-01

    Oxidative tailoring of C(40) carotenoids by double bond-specific cleavage enzymes (carotenoid cleavage dioxygenases, CCDs) gives rise to various apocarotenoids. AtCCD1 generating C(13) and C(14) apocarotenoids and orthologous enzymes in other plants are the only CCDs acting in the cytosol, while the hitherto presumed C(40) substrate is localized in the plastid. A new model for CCD1 action arising from a RNAi-mediated CCD1 gene silencing study in mycorrhizal hairy roots of Medicago truncatula may solve this contradiction. This approach unexpectedly resulted in the accumulation of C(27) apocarotenoids but not C(40) carotenoids suggesting C(27) as the main substrates for CCD1 in planta. It further implies a consecutive two-step cleavage process, in which another CCD performs the primary cleavage of C(40) to C(27) in the plastid followed by C(27) export and further cleavage by CCD1 in the cytosol. We compare the specificities and subcellular locations of the various CCDs and propose the plastidial CCD7 to be the first player in mycorrhizal apocarotenoid biogenesis.

  15. Role of carotenoid cleavage dioxygenase 1 (CCD1) in apocarotenoid biogenesis revisited

    PubMed Central

    Floss, Daniela S

    2009-01-01

    Oxidative tailoring of C40 carotenoids by double bond-specific cleavage enzymes (carotenoid cleavage dioxygenases, CCDs) gives rise to various apocarotenoids. AtCCD1 generating C13 and C14 apocarotenoids and orthologous enzymes in other plants are the only CCDs acting in the cytosol, while the hitherto presumed C40 substrate is localized in the plastid. A new model for CCD1 action arising from a RNAi-mediated CCD1 gene silencing study in mycorrhizal hairy roots of Medicago truncatula may solve this contradiction. This approach unexpectedly resulted in the accumulation of C27 apocarotenoids but not C40 carotenoids suggesting C27 as the main substrates for CCD1 in planta. It further implies a consecutive two-step cleavage process, in which another CCD performs the primary cleavage of C40 to C27 in the plastid followed by C27 export and further cleavage by CCD1 in the cytosol. We compare the specificities and subcellular locations of the various CCDs and propose the plastidial CCD7 to be the first player in mycorrhizal apocarotenoid biogenesis. PMID:19721743

  16. Tissue-Specific Apocarotenoid Glycosylation Contributes to Carotenoid Homeostasis in Arabidopsis Leaves1

    PubMed Central

    Hübner, Michaela; Matsubara, Shizue; Beyer, Peter

    2015-01-01

    Attaining defined steady-state carotenoid levels requires balancing of the rates governing their synthesis and metabolism. Phytoene formation mediated by phytoene synthase (PSY) is rate limiting in the biosynthesis of carotenoids, whereas carotenoid catabolism involves a multitude of nonenzymatic and enzymatic processes. We investigated carotenoid and apocarotenoid formation in Arabidopsis (Arabidopsis thaliana) in response to enhanced pathway flux upon PSY overexpression. This resulted in a dramatic accumulation of mainly β-carotene in roots and nongreen calli, whereas carotenoids remained unchanged in leaves. We show that, in chloroplasts, surplus PSY was partially soluble, localized in the stroma and, therefore, inactive, whereas the membrane-bound portion mediated a doubling of phytoene synthesis rates. Increased pathway flux was not compensated by enhanced generation of long-chain apocarotenals but resulted in higher levels of C13 apocarotenoid glycosides (AGs). Using mutant lines deficient in carotenoid cleavage dioxygenases (CCDs), we identified CCD4 as being mainly responsible for the majority of AGs formed. Moreover, changed AG patterns in the carotene hydroxylase mutants lutein deficient1 (lut1) and lut5 exhibiting altered leaf carotenoids allowed us to define specific xanthophyll species as precursors for the apocarotenoid aglycons detected. In contrast to leaves, carotenoid hyperaccumulating roots contained higher levels of β-carotene-derived apocarotenals, whereas AGs were absent. These contrasting responses are associated with tissue-specific capacities to synthesize xanthophylls, which thus determine the modes of carotenoid accumulation and apocarotenoid formation. PMID:26134165

  17. Tissue-Specific Apocarotenoid Glycosylation Contributes to Carotenoid Homeostasis in Arabidopsis Leaves.

    PubMed

    Lätari, Kira; Wüst, Florian; Hübner, Michaela; Schaub, Patrick; Beisel, Kim Gabriele; Matsubara, Shizue; Beyer, Peter; Welsch, Ralf

    2015-08-01

    Attaining defined steady-state carotenoid levels requires balancing of the rates governing their synthesis and metabolism. Phytoene formation mediated by phytoene synthase (PSY) is rate limiting in the biosynthesis of carotenoids, whereas carotenoid catabolism involves a multitude of nonenzymatic and enzymatic processes. We investigated carotenoid and apocarotenoid formation in Arabidopsis (Arabidopsis thaliana) in response to enhanced pathway flux upon PSY overexpression. This resulted in a dramatic accumulation of mainly β-carotene in roots and nongreen calli, whereas carotenoids remained unchanged in leaves. We show that, in chloroplasts, surplus PSY was partially soluble, localized in the stroma and, therefore, inactive, whereas the membrane-bound portion mediated a doubling of phytoene synthesis rates. Increased pathway flux was not compensated by enhanced generation of long-chain apocarotenals but resulted in higher levels of C13 apocarotenoid glycosides (AGs). Using mutant lines deficient in carotenoid cleavage dioxygenases (CCDs), we identified CCD4 as being mainly responsible for the majority of AGs formed. Moreover, changed AG patterns in the carotene hydroxylase mutants lutein deficient1 (lut1) and lut5 exhibiting altered leaf carotenoids allowed us to define specific xanthophyll species as precursors for the apocarotenoid aglycons detected. In contrast to leaves, carotenoid hyperaccumulating roots contained higher levels of β-carotene-derived apocarotenals, whereas AGs were absent. These contrasting responses are associated with tissue-specific capacities to synthesize xanthophylls, which thus determine the modes of carotenoid accumulation and apocarotenoid formation. © 2015 American Society of Plant Biologists. All Rights Reserved.

  18. Shedding light on NO homeostasis: Light as a key regulator of glutathione and nitric oxide metabolisms during seedling deetiolation.

    PubMed

    Zuccarelli, Rafael; Coelho, Aline C P; Peres, Lazaro E P; Freschi, Luciano

    2017-01-18

    Despite the significant impacts of light on nitric oxide (NO) levels in plants, the mechanism underlying the influence of this environmental factor on NO metabolism remains poorly understood. A critical mechanism controlling NO levels in plant cells relies on the S-nitrosylation of glutathione (GSH), giving rise to S-nitrosoglutathione (GSNO), which can be either stored or degraded depending on the cellular context. Here, we demonstrate that a strict balance is maintained between NO generation and scavenging during tomato (Solanum lycopersicum) seedling deetiolation. Given the absence of accurate methods in the literature to estimate NO scavenging in planta, we first developed a simple, robust system to continuously monitor the global in vivo NO scavenging by plant tissues. Then, using photomorphogenic tomato mutants, we demonstrated that the light-evoked de-etiolation is associated with a dramatic rise in NO content followed by a progressive increment in NO scavenging capacity of the tissues. Light-driven increments in NO scavenging rates coincided with pronounced rises in S-nitrosothiol content and GSNO reductase (GSNOR) activity, thereby suggesting that GSNO formation and subsequent removal via GSNOR might be key for controlling NO levels during seedling deetiolation. Accordingly, treatments with thiol-blocking compounds further indicated that thiol nitrosylation might be critically involved in the NO scavenging mechanism responsible for maintaining NO homeostasis during deetiolation. The impacts of both light and NO on the transcriptional profile of glutathione metabolic genes also revealed an independent but coordinated action of these signals on the regulation of key components of glutathione and GSNO metabolisms. Altogether, these data indicated that GSNO formation and subsequent removal might facilitate maintaining NO homeostasis during light-driven seedling deetiolation.

  19. Evidence of coat color variation sheds new light on ancient canids.

    PubMed

    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 K(B) 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.

  20. 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

  1. 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

  2. Single-molecule fluorescence microscopy review: shedding new light on old problems

    PubMed Central

    Shashkova, Sviatlana

    2017-01-01

    Fluorescence microscopy is an invaluable tool in the biosciences, a genuine workhorse technique offering exceptional contrast in conjunction with high specificity of labelling with relatively minimal perturbation to biological samples compared with many competing biophysical techniques. Improvements in detector and dye technologies coupled to advances in image analysis methods have fuelled recent development towards single-molecule fluorescence microscopy, which can utilize light microscopy tools to enable the faithful detection and analysis of single fluorescent molecules used as reporter tags in biological samples. For example, the discovery of GFP, initiating the so-called ‘green revolution’, has pushed experimental tools in the biosciences to a completely new level of functional imaging of living samples, culminating in single fluorescent protein molecule detection. Today, fluorescence microscopy is an indispensable tool in single-molecule investigations, providing a high signal-to-noise ratio for visualization while still retaining the key features in the physiological context of native biological systems. In this review, we discuss some of the recent discoveries in the life sciences which have been enabled using single-molecule fluorescence microscopy, paying particular attention to the so-called ‘super-resolution’ fluorescence microscopy techniques in live cells, which are at the cutting-edge of these methods. In particular, how these tools can reveal new insights into long-standing puzzles in biology: old problems, which have been impossible to tackle using other more traditional tools until the emergence of new single-molecule fluorescence microscopy techniques. PMID:28694303

  3. Shedding light on plant competition: modelling the influence of plant morphology on light capture (and vice versa).

    PubMed

    Clark, Ben; Bullock, Seth

    2007-01-21

    A plant's morphology is both strongly influenced by local light availability and, simultaneously, strongly influences this local light availability. This reciprocal relationship is complex, but lies at the heart of understanding plant growth and competition. Here, we develop a sub-individual-based simulation model, cast at the level of interacting plant components. The model explicitly simulates growth, development and competition for light at the level of leaves, branches, etc., located in 3D space. In this way, we are able to explore the manner in which the low-level processes governing plant growth and development give rise to individual-, cohort-, and community-level phenomena. In particular, we show that individual-level trade-offs between growing up and growing out arise naturally in the model, and robustly give rise to cohort-level phenomena such as self-thinning, and community processes such as the effect of ecological disturbance on the maintenance of biodiversity. We conclude with a note on our methodology and how to interpret the results of simulation models such as this one.

  4. 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

  5. Epigenomic k-mer dictionaries: shedding light on how sequence composition influences in vivo nucleosome positioning.

    PubMed

    Giancarlo, Raffaele; Rombo, Simona E; Utro, Filippo

    2015-09-15

    Information-theoretic and compositional analysis of biological sequences, in terms of k-mer dictionaries, has a well established role in genomic and proteomic studies. Much less so in epigenomics, although the role of k-mers in chromatin organization and nucleosome positioning is particularly relevant. Fundamental questions concerning the informational content and compositional structure of nucleosome favouring and disfavoring sequences with respect to their basic building blocks still remain open. We present the first analysis on the role of k-mers in the composition of nucleosome enriched and depleted genomic regions (NER and NDR for short) that is: (i) exhaustive and within the bounds dictated by the information-theoretic content of the sample sets we use and (ii) informative for comparative epigenomics. We analize four different organisms and we propose a paradigmatic formalization of k-mer dictionaries, providing two different and complementary views of the k-mers involved in NER and NDR. The first extends well known studies in this area, its comparative nature being its major merit. The second, very novel, brings to light the rich variety of k-mers involved in influencing nucleosome positioning, for which an initial classification in terms of clusters is also provided. Although such a classification offers many insights, the following deserves to be singled-out: short poly(dA:dT) tracts are reported in the literature as fundamental for nucleosome depletion, however a global quantitative look reveals that their role is much less prominent than one would expect based on previous studies. Dictionaries, clusters and Supplementary Material are available online at http://math.unipa.it/rombo/epigenomics/. simona.rombo@unipa.it Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

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

    PubMed

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

    2013-01-02

    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.

  7. Structural and Functional Analysis of STING Sheds New Light on Cyclic di-GMP Mediated Immune Signaling Mechanism

    PubMed Central

    Ouyang, Songying; Song, Xianqiang; Wang, Yaya; Ru, Heng; Shaw, Neil; Jiang, Yan; Niu, Fengfeng; Zhu, Yanping; Qiu, Weicheng; Parvatiyar, Kislay; Li, Yang; Zhang, Rongguang; Cheng, Genhong; Liu, Zhi-Jie

    2012-01-01

    SUMMARY STING is an essential signaling molecule for DNA and cyclic di-GMP (c-di-GMP)-mediated type I interferon (IFN) production via TANK-binding kinase 1 (TBK1) and Interferon regulatory factor 3 (IRF3) pathway. It contains an N-terminal transmembrane region and a cytosolic C-terminal domain (CTD). Here, we describe crystal structures of STING CTD alone and complexed with c-di-GMP in a unique binding mode. The strictly conserved AA153-173 region was shown to be cytosolic and participated in dimerization via hydrophobic interactions. The STING CTD functions as a dimer and the dimerization was independent of post-translational modifications. Binding of c-di-GMP enhanced interaction of a shorter construct of STING CTD (residues 139-344) with TBK1. This suggests an extra TBK1 binding site, other than Ser358. This study provides a glimpse into the unique architecture of STING and sheds new light on the mechanism of c-di-GMP-mediated TBK1 signaling. PMID:22579474

  8. 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

  9. 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

  10. Shedding Light on Photophobia

    PubMed Central

    Digre, Kathleen B.; Brennan, K.C.

    2012-01-01

    Photophobia is a common yet debilitating symptom seen in many ophthalmic and neurologic disorders. Despite its prevalence, it is poorly understood and difficult to treat. However, the past few years have seen significant advances in our understanding of this symptom. We review the clinical characteristics and disorders associated with photophobia, discuss the anatomy and physiology of this phenomenon, and conclude with a practical approach to diagnosis and treatment. PMID:22330853

  11. Comprehensive transcriptome analysis of Crocus sativus for discovery and expression of genes involved in apocarotenoid biosynthesis.

    PubMed

    Baba, Shoib Ahmad; Mohiuddin, Tabasum; Basu, Swaraj; Swarnkar, Mohit Kumar; Malik, Aubid Hussain; Wani, Zahoor Ahmed; Abbas, Nazia; Singh, Anil Kumar; Ashraf, Nasheeman

    2015-09-15

    Crocus sativus stigmas form rich source of apocarotenoids like crocin, picrocrocin and saffranal which besides imparting color, flavour and aroma to saffron spice also have tremendous pharmacological properties. Inspite of their importance, the biosynthetic pathway of Crocus apocarotenoids is not fully elucidated. Moreover, the mechanism of their stigma specific accumulation remains unknown. Therefore, deep transcriptome sequencing of Crocus stigma and rest of the flower tissue was done to identify the genes and transcriptional regulators involved in the biosynthesis of these compounds. Transcriptome of stigma and rest of the flower tissue was sequenced using Illumina Genome Analyzer IIx platform which generated 64,604,402 flower and 51,350,714 stigma reads. Sequences were assembled de novo using trinity resulting in 64,438 transcripts which were classified into 32,204 unigenes comprising of 9853 clusters and 22,351 singletons. A comprehensive functional annotation and gene ontology (GO) analysis was carried out. 58.5 % of the transcripts showed similarity to sequences present in public databases while rest could be specific to Crocus. 5789 transcripts showed similarity to transcription factors representing 76 families out of which Myb family was most abundant. Many genes involved in carotenoid/apocarotenoid pathway were identified for the first time in this study which includes zeta-carotene isomerase and desaturase, carotenoid isomerase and lycopene epsilon-cyclase. GO analysis showed that the predominant classes in biological process category include metabolic process followed by cellular process and primary metabolic process. KEGG mapping analysis indicated that pathways involved in ribosome, carbon and starch and sucrose metabolism were highly represented. Differential expression analysis indicated that key carotenoid/apocarotenoid pathway genes including phytoene synthase, phytoene desaturase and carotenoid cleavage dioxygenase 2 are enriched in stigma

  12. Chemical identification and functional analysis of apocarotenoids involved in the development of arbuscular mycorrhizal symbiosis.

    PubMed

    Akiyama, Kohki

    2007-06-01

    Arbuscular mycorrhizae formed between more than 80% of land plants and arbuscular mycorrhizal (AM) fungi represent the most widespread symbiosis on the earth. AM fungi facilitate the uptake of soil nutrients, especially phosphate, by plants, and in return obtain carbohydrates from hosts. Apocarotenoids, oxidative cleavage products of carotenoids, have been found to play a critical role in the establishment of AM symbiosis. Strigolactones previously isolated as seed-germination stimulants for root parasitic weeds act as a chemical signal for AM fungi during presymbiotic stages. Stimulation of carotenoid metabolism, leading to massive accumulation of mycorradicin and cyclohexenone derivatives, occurs during root colonization by AM fungi. This review highlights research into the chemical identification of arbuscular mycorrhiza-related apocarotenoids and their role in the regulation and establishment of AM symbiosis conducted in the past 10 years.

  13. ITS polymorphisms shed light on hybrid evolution in apomictic plants: a case study on the Ranunculus auricomus complex.

    PubMed

    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

  14. 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

  15. Carotenoid metabolism in mammals, including man: formation, occurrence, and function of apocarotenoids

    PubMed Central

    Eroglu, Abdulkerim; Harrison, Earl H.

    2013-01-01

    Vitamin A was recognized as an essential nutrient 100 years ago. In the 1930s, it became clear that dietary β-carotene was cleaved at its central double to yield vitamin A (retinal or β-apo-15′-carotenal). Thus a great deal of research has focused on the central cleavage of provitamin A carotenoids to form vitamin A (retinoids). The mechanisms of formation and the physiological role(s) of noncentral (eccentric) cleavage of both provitamin A carotenoids and nonprovitamin A carotenoids has been less clear. It is becoming apparent that the apocarotenoids exert unique biological activities themselves. These compounds are found in the diet and thus may be absorbed in the intestine, or they may form from enzymatic or nonenzymatic cleavage of the parent carotenoids. The mechanism of action of apocarotenoids in mammals is not fully worked out. However, as detailed in this review, they have profound effects on gene expression and work, at least in part, through the modulation of ligand-activated nuclear receptors. Understanding the interactions of apocarotenoids with other lipid-binding proteins, chaperones, and metabolizing enzymes will undoubtedly increase our understanding of the biological roles of these carotenoid metabolites. PMID:23667178

  16. Overexpression of the rice carotenoid cleavage dioxygenase 1 gene in Golden Rice endosperm suggests apocarotenoids as substrates in planta.

    PubMed

    Ilg, Andrea; Yu, Qiuju; Schaub, Patrick; Beyer, Peter; Al-Babili, Salim

    2010-08-01

    Carotenoids are converted by carotenoid cleavage dioxygenases that catalyze oxidative cleavage reactions leading to apocarotenoids. However, apocarotenoids can also be further truncated by some members of this enzyme family. The plant carotenoid cleavage dioxygenase 1 (CCD1) subfamily is known to degrade both carotenoids and apocarotenoids in vitro, leading to different volatile compounds. In this study, we investigated the impact of the rice CCD1 (OsCCD1) on the pigmentation of Golden Rice 2 (GR2), a genetically modified rice variety accumulating carotenoids in the endosperm. For this purpose, the corresponding cDNA was introduced into the rice genome under the control of an endosperm-specific promoter in sense and anti-sense orientations. Despite high expression levels of OsCCD1 in sense plants, pigment analysis revealed carotenoid levels and patterns comparable to those of GR2, pleading against carotenoids as substrates in rice endosperm. In support, similar carotenoid contents were determined in anti-sense plants. To check whether OsCCD1 overexpressed in GR2 endosperm is active, in vitro assays were performed with apocarotenoid substrates. HPLC analysis confirmed the cleavage activity of introduced OsCCD1. Our data indicate that apocarotenoids rather than carotenoids are the substrates of OsCCD1 in planta.

  17. Trade-offs between light interception and leaf water shedding: a comparison of shade- and sun-adapted species in a subtropical rainforest.

    PubMed

    Meng, Fengqun; Cao, Rui; Yang, Dongmei; Niklas, Karl J; Sun, Shucun

    2014-01-01

    Species in high-rainfall regions have two major alternative approaches to quickly drain off water, i.e., increasing leaf inclination angles relative to the horizontal plane, or developing long leaf drip tips. We hypothesized that shade-adapted species will have more pronounced leaf drip tips but not greater inclination angles (which can reduce the ability to intercept light) compared to sun-adapted species and that length of leaf drip tips will be negatively correlated with photosynthetic capacity [characterized by light-saturated net photosynthetic rates (Amax), associated light compensation points (LCP), and light saturation points (LSP)]. We tested this hypothesis by measuring morphological and physiological traits that are associated with light-interception and water shedding for seven shade-adapted shrub species, ten sun-adapted understory shrub species, and 15 sun-adapted tree species in a subtropical Chinese rainforest, where mean annual precipitation is around 1,600 mm. Shade-adapted understory species had lower LMA, Amax, LSP, and LCP compared to understory or canopy sun-adapted species; their leaf and twig inclination angles were significantly smaller and leaf drip tips were significantly longer than those in sun-adapted species. This suggests that shade-adapted understory species tend to develop pronounced leaf drip tips but not large leaf inclination angles to shed water. The length of leaf drip tips was negatively correlated with leaf inclination angles and photosynthetic capacity. These relationships were consistent between ordinary regression and phylogenetic generalized least squares analyses. Our study illustrates the trade-offs between light interception and leaf water shedding and indicates that length of leaf drip tips can be used as an indicator of adaptation to shady conditions and overall photosynthetic performance of shrub species in subtropical rainforests.

  18. Retinal is formed from apo-carotenoids in Nostoc sp. PCC7120: in vitro characterization of an apo-carotenoid oxygenase

    PubMed Central

    Scherzinger, Daniel; Ruch, Sandra; Kloer, Daniel P.; Wilde, Annegret; Al-Babili, Salim

    2006-01-01

    The sensory rhodopsin from Anabaena (Nostoc) sp. PCC7120 is the first cyanobacterial retinylidene protein identified. Here, we report on NosACO (Nostoc apo-carotenoid oxygenase), encoded by the ORF (open reading frame) all4284, as the candidate responsible for the formation of the required chromophore, retinal. In contrast with the enzymes from animals, NosACO converts β-apo-carotenals instead of β-carotene into retinal in vitro. The identity of the enzymatic products was proven by HPLC and gas chromatography–MS. NosACO exhibits a wide substrate specificity with respect to chain lengths and functional end-groups, converting β-apo-carotenals, (3R)-3-hydroxy-β-apo-carotenals and the corresponding alcohols into retinal and (3R)-3-hydroxyretinal respectively. However, kinetic analyses revealed very divergent Km and Vmax values. On the basis of the crystal structure of SynACO (Synechocystis sp. PCC6803 apo-carotenoid oxygenase), a related enzyme showing similar enzymatic activity, we designed a homology model of the native NosACO. The deduced structure explains the absence of β-carotene-cleavage activity and indicates that NosACO is a monotopic membrane protein. Accordingly, NosACO could be readily reconstituted into liposomes. To localize SynACO in vivo, a Synechocystis knock-out strain was generated expressing SynACO as the sole carotenoid oxygenase. Western-blot analyses showed that the main portion of SynACO occurred in a membrane-bound form. PMID:16759173

  19. De novo transcriptome assembly and comprehensive expression profiling in Crocus sativus to gain insights into apocarotenoid biosynthesis

    PubMed Central

    Jain, Mukesh; Srivastava, Prabhakar Lal; Verma, Mohit; Ghangal, Rajesh; Garg, Rohini

    2016-01-01

    Saffron (Crocus sativus L.) is commonly known as world’s most expensive spice with rich source of apocarotenoids and possesses magnificent medicinal properties. To understand the molecular basis of apocarotenoid biosynthesis/accumulation, we performed transcriptome sequencing from five different tissues/organs of C. sativus using Illumina platform. After comprehensive optimization of de novo transcriptome assembly, a total of 105, 269 unique transcripts (average length of 1047 bp and N50 length of 1404 bp) were obtained from 206 million high-quality paired-end reads. Functional annotation led to the identification of many genes involved in various biological processes and molecular functions. In total, 54% of C. sativus transcripts could be functionally annotated using public databases. Transcriptome analysis of C. sativus revealed the presence of 16721 SSRs and 3819 transcription factor encoding transcripts. Differential expression analysis revealed preferential/specific expression of many transcripts involved in apocarotenoid biosynthesis in stigma. We have revealed the differential expression of transcripts encoding for transcription factors (MYB, MYB related, WRKY, C2C2-YABBY and bHLH) involved in secondary metabolism. Overall, these results will pave the way for understanding the molecular basis of apocarotenoid biosynthesis and other aspects of stigma development in C. sativus. PMID:26936416

  20. De novo transcriptome assembly and comprehensive expression profiling in Crocus sativus to gain insights into apocarotenoid biosynthesis.

    PubMed

    Jain, Mukesh; Srivastava, Prabhakar Lal; Verma, Mohit; Ghangal, Rajesh; Garg, Rohini

    2016-03-03

    Saffron (Crocus sativus L.) is commonly known as world's most expensive spice with rich source of apocarotenoids and possesses magnificent medicinal properties. To understand the molecular basis of apocarotenoid biosynthesis/accumulation, we performed transcriptome sequencing from five different tissues/organs of C. sativus using Illumina platform. After comprehensive optimization of de novo transcriptome assembly, a total of 105, 269 unique transcripts (average length of 1047 bp and N50 length of 1404 bp) were obtained from 206 million high-quality paired-end reads. Functional annotation led to the identification of many genes involved in various biological processes and molecular functions. In total, 54% of C. sativus transcripts could be functionally annotated using public databases. Transcriptome analysis of C. sativus revealed the presence of 16721 SSRs and 3819 transcription factor encoding transcripts. Differential expression analysis revealed preferential/specific expression of many transcripts involved in apocarotenoid biosynthesis in stigma. We have revealed the differential expression of transcripts encoding for transcription factors (MYB, MYB related, WRKY, C2C2-YABBY and bHLH) involved in secondary metabolism. Overall, these results will pave the way for understanding the molecular basis of apocarotenoid biosynthesis and other aspects of stigma development in C. sativus.

  1. Systems biology study of transcriptional and post-transcriptional co-regulatory network sheds light on key regulators involved in important biological processes in Citrus sinensis.

    PubMed

    Khodadadi, Ehsan; Mehrabi, Ali Ashraf; Najafi, Ali; Rastad, Saber; Masoudi-Nejad, Ali

    2017-04-01

    Transcriptional and post-transcriptional regulators including transcription regulator, transcription factor and miRNA are the main endogenous molecular elements which control complex cellular mechanisms such as development, growth and response to biotic and abiotic stresses in a coordinated manner in plants. Utilizing the most recent information on such relationships in a plant species, obtained from high-throughput experimental technologies and advanced computational tools, we can reconstruct its co-regulatory network which consequently sheds light on key regulators involved in its important biological processes. In this article, combined systems biology approaches such as mining the literatures, various databases and network reconstruction, analysis, and visualization tools were employed to infer and visualize the coregulatory relationships between miRNAs and transcriptional regulators in Citrus sinensis. Using computationally and experimentally verified miRNA-target interactions and constructed co-expression networks on array-based data, 10 coregulatory networks and 10 corresponding subgraphs include FFL motifs were obtained for 10 distinct tissues/conditions. Then PPI subnetworks were extracted for transcripts/genes included in mentioned subgraphs in order to the functional analysis of extracted coregulatory circuits. These proposed coregulatory connections shed light on precisely identifying C. sinensis metabolic pathways key switches, which are demanded for ultimate goals such as genome editing.

  2. When LEP and Tevatron combined with WMAP and XENON100 shed light on the nature of dark matter

    SciTech Connect

    Mambrini, Yann; Zaldívar, Bryan E-mail: Bryan.Zaldivar@uam.es

    2011-10-01

    Recently, several astrophysical data or would-be signals has been observed in different dark-matter oriented experiments. In each case, one could fit the data at the price of specific nature of the coupling between the Standard Model (SM) particles and a light Dark Matter candidate: hadrophobic (INTEGRAL, PAMELA) or leptophobic (WMAP Haze, dijet anomalies of CDF, FERMI Galactic Center observation). In this work, we show that when one takes into account the more recent LEP and Tevatron analysis, a light thermal fermionic Dark Matter (∼<10 GeV) that couples to electrons is mainly ruled out if one combines the analysis with WMAP constraints. We also study the special case of scalar dark matter, using a single-photon events simulation to constrain the coupling of dark matter to electron.

  3. Shedding light on cell compartmentation in the candidate phylum Poribacteria by high resolution visualisation and transcriptional profiling

    NASA Astrophysics Data System (ADS)

    Jahn, Martin T.; Markert, Sebastian M.; Ryu, Taewoo; Ravasi, Timothy; Stigloher, Christian; Hentschel, Ute; Moitinho-Silva, Lucas

    2016-10-01

    Assigning functions to uncultivated environmental microorganisms continues to be a challenging endeavour. Here, we present a new microscopy protocol for fluorescence in situ hybridisation-correlative light and electron microscopy (FISH-CLEM) that enabled, to our knowledge for the first time, the identification of single cells within their complex microenvironment at electron microscopy resolution. Members of the candidate phylum Poribacteria, common and uncultivated symbionts of marine sponges, were used towards this goal. Cellular 3D reconstructions revealed bipolar, spherical granules of low electron density, which likely represent carbon reserves. Poribacterial activity profiles were retrieved from prokaryotic enriched sponge metatranscriptomes using simulation-based optimised mapping. We observed high transcriptional activity for proteins related to bacterial microcompartments (BMC) and we resolved their subcellular localisation by combining FISH-CLEM with immunohistochemistry (IHC) on ultra-thin sponge tissue sections. In terms of functional relevance, we propose that the BMC-A region may be involved in 1,2-propanediol degradation. The FISH-IHC-CLEM approach was proven an effective toolkit to combine -omics approaches with functional studies and it should be widely applicable in environmental microbiology.

  4. 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.

  5. Did the great masters "cheat" using optics? Image analysis of Renaissance masterpieces sheds light on a bold theory

    NASA Astrophysics Data System (ADS)

    Stork, David

    2006-12-01

    In 2001, artist David Hockney and scientist Charles Falco stunned the art world with a controversial theory that, if correct, would profoundly alter our view of the development of image making. They claimed that as early as 1420, Renaissance artists employed optical devices such as concave mirrors to project images onto their canvases, which they then traced or painted over. In this way, the theory attempts to explain the newfound heightened naturalism or "opticality" of painters such as Jan van Eyck, Robert Campin, Hans Holbein the Younger, and many others. This talk will describe the application of rigorous computer image analysis to masterpieces adduced as evidence for this theory. It covers basic geometrical optics of image projection, the analysis of perspective, curved surface reflections, shadows, lighting and color. While there remain some loose ends, such analysis of the paintings, infra-red reflectograms, modern reenactments, internal consistency of the theory, and alternate explanations allows us to judge with high confidence the plausibility of this bold theory. You may never see Renaissance paintings the same way again.

  6. Convergent evolution sheds light on the anti-β-elimination mechanism common to family 1 and 10 polysaccharide lyases

    PubMed Central

    Charnock, Simon J.; Brown, Ian E.; Turkenburg, Johan P.; Black, Gary W.; Davies, Gideon J.

    2002-01-01

    Enzyme-catalyzed β-elimination of sugar uronic acids, exemplified by the degradation of plant cell wall pectins, plays an important role in a wide spectrum of biological processes ranging from the recycling of plant biomass through to pathogen virulence. The three-dimensional crystal structure of the catalytic module of a “family PL-10” polysaccharide lyase, Pel10Acm from Cellvibrio japonicus, solved at a resolution of 1.3 Å, reveals a new polysaccharide lyase fold and is the first example of a polygalacturonic acid lyase that does not exhibit the “parallel β-helix” topology. The “Michaelis” complex of an inactive mutant in association with the substrate trigalacturonate/Ca2+ reveals the catalytic machinery harnessed by this polygalacturonate lyase, which displays a stunning resemblance, presumably through convergent evolution, to the tetragalacturonic acid complex observed for a structurally unrelated polygalacturonate lyase from family PL-1. Common coordination of the −1 and +1 subsite saccharide carboxylate groups by a protein-liganded Ca2+ ion, the positioning of an arginine catalytic base in close proximity to the α-carbon hydrogen and numerous other conserved enzyme–substrate interactions, considered in light of mutagenesis data for both families, suggest a generic polysaccharide anti-β-elimination mechanism. PMID:12221284

  7. 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.

  8. Shedding light on the expansion and diversification of the Cdc48 protein family during the rise of the eukaryotic cell.

    PubMed

    Kienle, Nickias; Kloepper, Tobias H; Fasshauer, Dirk

    2016-10-18

    A defining feature of eukaryotic cells is the presence of various distinct membrane-bound compartments with different metabolic roles. Material exchange between most compartments occurs via a sophisticated vesicle trafficking system. This intricate cellular architecture of eukaryotes appears to have emerged suddenly, about 2 billion years ago, from much less complex ancestors. How the eukaryotic cell acquired its internal complexity is poorly understood, partly because no prokaryotic precursors have been found for many key factors involved in compartmentalization. One exception is the Cdc48 protein family, which consists of several distinct classical ATPases associated with various cellular activities (AAA+) proteins with two consecutive AAA domains. Here, we have classified the Cdc48 family through iterative use of hidden Markov models and tree building. We found only one type, Cdc48, in prokaryotes, although a set of eight diverged members that function at distinct subcellular compartments were retrieved from eukaryotes and were probably present in the last eukaryotic common ancestor (LECA). Pronounced changes in sequence and domain structure during the radiation into the LECA set are delineated. Moreover, our analysis brings to light lineage-specific losses and duplications that often reflect important biological changes. Remarkably, we also found evidence for internal duplications within the LECA set that probably occurred during the rise of the eukaryotic cell. Our analysis corroborates the idea that the diversification of the Cdc48 family is closely intertwined with the development of the compartments of the eukaryotic cell.

  9. Shedding light on cell compartmentation in the candidate phylum Poribacteria by high resolution visualisation and transcriptional profiling

    PubMed Central

    Jahn, Martin T.; Markert, Sebastian M.; Ryu, Taewoo; Ravasi, Timothy; Stigloher, Christian; Hentschel, Ute; Moitinho-Silva, Lucas

    2016-01-01

    Assigning functions to uncultivated environmental microorganisms continues to be a challenging endeavour. Here, we present a new microscopy protocol for fluorescence in situ hybridisation-correlative light and electron microscopy (FISH-CLEM) that enabled, to our knowledge for the first time, the identification of single cells within their complex microenvironment at electron microscopy resolution. Members of the candidate phylum Poribacteria, common and uncultivated symbionts of marine sponges, were used towards this goal. Cellular 3D reconstructions revealed bipolar, spherical granules of low electron density, which likely represent carbon reserves. Poribacterial activity profiles were retrieved from prokaryotic enriched sponge metatranscriptomes using simulation-based optimised mapping. We observed high transcriptional activity for proteins related to bacterial microcompartments (BMC) and we resolved their subcellular localisation by combining FISH-CLEM with immunohistochemistry (IHC) on ultra-thin sponge tissue sections. In terms of functional relevance, we propose that the BMC-A region may be involved in 1,2-propanediol degradation. The FISH-IHC-CLEM approach was proven an effective toolkit to combine -omics approaches with functional studies and it should be widely applicable in environmental microbiology. PMID:27796326

  10. Shedding lights on the flexible-armed porphyrins: Human telomeric G4 DNA interaction and cell photocytotoxicity research.

    PubMed

    Sun, Xiang-Yu; Zhao, Ping; Jin, Shu-Fang; Liu, Min-Chao; Wang, Xia-Hong; Huang, Yu-Min; Cheng, Zhen-Feng; Yan, Si-Qi; Li, Yan-Yu; Chen, Ya-Qing; Zhong, Yan-Mei

    2017-08-01

    DNA polymorphism exerts a fascination on a large scientific community. Without crystallographic structural data, clarification of the binding modes between G-quadruplex (G4) and ligand (complex) is a challenging job. In the present work, three porphyrin compounds with different flexible carbon chains (arms) were designed, synthesized and characterized. Their binding, folding and stabilizing abilities to human telomeric G4 DNA structures were comparatively researched. Positive charges at the end of the flexible carbon chains seem to be favorable for the DNA-porphyrin interactions, which were evidenced by the spectral results and further confirmed by the molecular docking calculations. Biological function analysis demonstrated that these porphyrins show no substantial inhibition to Hela, A549 and BEL 7402 cancer cell lines under dark while exhibit broad inhibition under visible light. This significantly enhanced photocytotoxicity relative to the dark control is an essential property of photochemotherapeutic agents. The feature of the flexible arms emerges as critical influencing factors in the cell photocytotoxicity. Moreover, an ROS-mediated mitochondrial dysfunction pathway was suggested for the cell apoptosis induced by these flexible-armed porphyrins. It is found that the porphyrins with positive charges located at the end of the flexible arms represent an exciting opportunity for photochemotherapeutic anti-cancer drug design. Copyright © 2017. Published by Elsevier B.V.

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

    PubMed

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

    2015-06-07

    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.

  12. 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

  13. Endemic palm species shed light on habitat shifts and the assembly of the Cerrado and Restinga floras.

    PubMed

    Bacon, Christine D; Moraes R, Monica; Jaramillo, Carlos; Antonelli, Alexandre

    2017-05-01

    Species expansions into new habitats are often associated with physiological adaptations, for instance when rain forest lineages colonize dry habitats. Although such shifts have been documented for the Brazilian savanna (Cerrado), little is known about the biogeographic origin of species occupying an extreme South American habitat type, the coastal dunes (Restinga). We examined the formation of this poorly known, endangered habitat by reconstructing the evolutionary history of two endemic species. Due to the proposed recency and uniqueness of this habitat, we hypothesized that Restinga species of the palm genus Allagoptera to be recently evolved and to present derived morphological characters. To detect habit shifts in absolute time, we used one plastid and nine nuclear genes to reconstruct the phylogenetic and biogeographic history of Allagoptera. We used light microscopy and stable isotope analysis to explore whether morphological adaptations occurred concomitantly with habitat shifts. Phylogenetic relationships were well supported and we found ancestral lineages of Allagoptera to be widely distributed throughout habitats that are currently occupied by extant species. Over the last ca. 7Ma Allagoptera has shifted its preference to increasingly dry habitats. Coincident with the colonization of the Cerrado and Restinga, morphological adaptations also evolved, including subterranean stems that are fire-resistant and long underground stem and root systems that facilitate water access. We did not find differences in metabolic pathway or modifications to pollen morphology when compared to other palm lineages. Assuming that the evolutionary history of Allagoptera is indicative of the habitat in which it occurs, our results infer a recent origin for Cerrado species. Although little is known about the formation of the Restinga habitat, our results also suggest a longer history than currently proposed; with an origin of Restinga habitats dating back to the Late Pliocene.

  14. 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.

  15. Shedding light on the structures of lignin compounds: photo-oxidation under artificial UV light and characterization by high resolution mass spectrometry.

    PubMed

    Qi, Yulin; Hempelmann, Rolf; Volmer, Dietrich A

    2016-11-01

    Lignin is the second most abundant natural polymer and a promising alternative energy source for conventional fossil fuels. In this study, we investigated transformations of lignin compounds under artificial UV light conditions at the molecular level. Such light-induced changes of composition profiles in nature after sun exposure have been studied for crude oil in the petroleomics field. We applied a similar high resolution mass spectrometry experimental strategy to lignin and demonstrated various data processing methods to reveal the characteristic differences between the extremely complex data sets of two sample sets, one native control before and one sample after photo-irradiation, using Fourier transform ion cyclotron resonance-mass spectrometry. Graphical abstract Kendrick mass defect versus nominal Kendrick mass for mass spectra of a control and UV-oxidized lignin sample.

  16. Molecular evolution and expression divergence of the Populus polygalacturonase supergene family shed light on the evolution of increasingly complex organs in plants.

    PubMed

    Yang, Zhi-Ling; Liu, Hai-Jing; Wang, Xiao-Ru; Zeng, Qing-Yin

    2013-03-01

    Plant polygalacturonases (PGs) are involved in cell separation processes during many stages of plant development. Investigation into the diversification of this large gene family in land plants could shed light on the evolution of structural development. We conducted whole-genome annotation, molecular evolution and gene expression analyses of PG genes in five species of land plant: Populus, Arabidopsis, rice, Selaginella and Physcomitrella. We identified 75, 44, 16 and 11 PG genes from Populus, rice, Selaginella and Physcomitrella genomes, respectively, which were divided into three classes. We inferred rapid expansion of class I PG genes in Populus, Arabidopsis and rice, while copy numbers of classes II and III PG genes were relatively conserved in all five species. Populus, Arabidopsis and rice class I PG genes were under more relaxed selection constraints than class II PG genes, while this selective pressure divergence was not observed in Selaginella and Physcomitrella PG families. In addition, class I PG genes underwent marked expression divergence in Populus, rice and Selaginella. Our results suggest that PG gene expansion occurred after the divergence of the lycophytes and euphyllophytes, and this expansion was likely paralleled by the evolution of increasingly complex organs in land plants.

  17. Animal models of bariatric/metabolic surgery shed light on the mechanisms of weight control and glucose homeostasis: view from the chair.

    PubMed

    Sharkey, K A

    2011-09-01

    Bariatric/metabolic surgeries are remarkably effective in reducing weight over a sustained period of time, and they also have significant beneficial effects on glucose homeostasis. Interestingly, the metabolic benefits of these surgeries frequently occur before significant weight loss. Given these findings, it is perhaps not surprising that obesity researchers are asking, how does bariatric/metabolic surgery work? Establishing these mechanisms can offer new insights into the physiology of energy balance and the control of metabolism. In the second half of the 13(th) International Symposium of the Merck Frosst/CIHR Research Chair in Obesity, four papers that address the mechanisms of bariatric/metabolic surgery were presented. The papers that follow this viewpoint all make use of animal models to reveal the neurohumoral mechanisms underlying weight loss and improved glucose homeostasis after experimental bariatric surgery. The rodent models of the commonly used clinical procedures have shown that energy intake is increased, food reward is altered and that the proximal gut is important in the control of energy balance and glucose homeostasis. Taken together, these models shed light on the mechanisms of bariatric/metabolic surgery and offer new insights that, in the future, may lead to less invasive therapies.

  18. 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.

  19. 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…

  20. 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…

  1. 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.

  2. 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…

  3. Shedding light on the past

    NASA Astrophysics Data System (ADS)

    Stampfl, A. P. J.; Friedman, E. S.; Wilkinson, T. J.; Alp, E. E.; Yener, K. A.

    2001-07-01

    The Amuq valley in southern Turkey is an important and interesting area in the Near East forming a space-time bridge for archaeologists and scientists to ancient and modern civilizations. The Lake of Antioch which evolved during the mid-late Holocene appears to have been located nearby some of the largest human settlements existing during this period. By documenting the conditions of the lake in time, using classical and modern approaches, the climate and geomorphology of the basin may be reconstructed. Synchrotron X-ray fluorescence measurements were performed on sections of a sedimentary core from the lake, representing an estimated 7500 yr of history. Analysis yielded the distribution of elemental masses spanning Ca to Mo as a function of depth from the surface. We find that the elemental concentrations measured follow a number of distinct patterns that may be related to local geomorphology, climate and human activities.

  4. [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.

  5. 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.

  6. 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…

  7. Shedding Light on Night Learning.

    ERIC Educational Resources Information Center

    Horwood, Bert

    1986-01-01

    Shows how darkness and night provide a potentially excellent arena for experiential learning opportunities. Recommends learning must be gradual, beginning with appreciation and allaying fear of the dark. Suggests sensory activities, hikes, games, aquatic activities, ecological simulations, historical presentations, and writing or reciting poetry.…

  8. Revisiting extraction of bioactive apocarotenoids from Crocus sativus L. dry stigmas (saffron).

    PubMed

    Kyriakoudi, Anastasia; Chrysanthou, Andreas; Mantzouridou, Fani; Tsimidou, Maria Z

    2012-11-28

    An ultrasound assisted extraction method is proposed for the recovery of bioactive glycosides (i.e. crocins and picrocrocin) from Crocus sativus L. dry stigmas using aqueous methanol. Response surface methodology (RSM) was employed to optimize the extraction parameters, namely, the percentage of methanol (%), the duration (min) and the duty cycles (s) of sonication. Optical microscopy, spectrophotometry and RP-HPLC-DAD were employed to follow pros and cons of the process. Additional experiments were conducted to compare recoveries with those under other agitation conditions (e.g. magnetic stirring according to ISO 3632-2 standard). The percentage of methanol, the sonication duration and duty cycles combination that can be recommended as optimum for the recovery of crocins and picrocrocin were 50%, 30 min, 0.2s and 0.44%, 30 min, 0.6s, respectively. Picrocrocin levels were not influenced dramatically under the optimum conditions for crocins extraction (11±2 instead of 12±1 mg kg(-1) dry stigmas, respectively) so that these can be considered optimum for both categories of tested compounds. Ultrasound assisted extraction speeded up further recovery of these precious apocarotenoids. Our findings for extraction conditions are useful for both industrial and analytical applications and should be considered in a forthcoming revision of the ISO 3632-2 technical standard. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. A functional zeaxanthin epoxidase from red algae shedding light on the evolution of light-harvesting carotenoids and the xanthophyll cycle in photosynthetic eukaryotes.

    PubMed

    Dautermann, Oliver; Lohr, Martin

    2017-09-26

    The epoxy-xanthophylls antheraxanthin and violaxanthin are key precursors of light-harvesting carotenoids and participate in the photoprotective xanthophyll cycle. Thus, the invention of zeaxanthin epoxidase (ZEP) catalyzing their formation from zeaxanthin has been a fundamental step in the evolution of photosynthetic eukaryotes. ZEP genes have only been found in Viridiplantae and chromalveolate algae with secondary plastids of red algal ancestry, suggesting that ZEP evolved in the Viridiplantae and spread to chromalveolates by lateral gene transfer. By searching publicly available sequence data from eleven red algae covering all currently recognized red algal classes we identified ZEP candidates in three species. Phylogenetic analyses showed that the red algal ZEP is most closely related to ZEP proteins from photosynthetic chromalveolates possessing secondary plastids of red algal origin. Its enzymatic activity was assessed by HPLC analyses of red algal pigment extracts and by cloning and functional expression of the ZEP gene from Madagascaria erythrocladioides in leaves of the ZEP-deficient aba2 mutant of Nicotiana plumbaginifolia. Unlike other ZEP enzymes examined so far, the red algal ZEP introduces only a single epoxy group into zeaxanthin, yielding antheraxanthin instead of violaxanthin. The results indicate that ZEP evolved before the split of Rhodophyta and Viridiplantae and that chromalveolates acquired ZEP from the red algal endosymbiont and not by lateral gene transfer. Moreover, the red algal ZEP enables engineering of transgenic plants incorporating antheraxanthin instead of violaxanthin in their photosynthetic machinery. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  10. New data from the Middle Jurassic of China shed light on the phylogeny and origin of the proboscis in the Mesopsychidae (Insecta: Mecoptera).

    PubMed

    Lin, Xiaodan; Shih, Matthew J H; Labandeira, Conrad C; Ren, Dong

    2016-01-04

    The Mesopsychidae is an extinct family of Mecoptera, comprising eleven described genera from Upper Permian to Lower Cretaceous deposits. In 2009, several well-preserved mesopsychids with long proboscides were reported from the mid Mesozoic of Northeastern China, suggesting the presence of pollination mutualisms with gymnosperm plants and highlighting their elevated genus-level diversity. Since that time, additional mesopsychid taxa have been described. However, the phylogeny of genera within Mesopsychidae has not been studied formally, attributable to the limited number of well-preserved fossils. Here, we describe two new species, Lichnomesopsyche prochorista sp. nov. and Vitimopsyche pristina sp. nov. and revise the diagnosis of Lichnomesopsyche daohugouensis Ren, Labandeira and Shih, 2010, based on ten specimens from the latest Middle Jurassic Jiulongshan Formation of Inner Mongolia, China. After compiling data from these new fossil species and previously reported representative taxa, we conducted phylogenetic analyses and geometric morphometric studies that now shed light on the taxonomy and phylogeny of Mesopsychidae. We also evaluate the recurring origin of the siphonate proboscis in the Mecoptera and propose an evolutionary developmental model for its multiple origins. Phylogenetic and geometric morphometric results confirm the establishment of two new species, each to Lichnomesopsyche and Vitimopsyche. Vitimopsyche pristina sp. nov. extends the existence of the genus Vitimopsyche Novokshonov and Sukacheva, 2001, from the mid Lower Cretaceous to the latest Middle Jurassic. Two methods of analyses indicate an affiliation of Mesopsyche dobrokhotovae Novokshonov, 1997 with Permopsyche Bashkuev, 2011. A phylogenetic analysis of the Mesopsychidae supports: 1), Mesopsychidae as a monophyletic group; 2), Mesopsyche as a paraphyletic group, to be revised pending future examination of additional material; and 3), the independent origin of the proboscis in the

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

    PubMed Central

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

    2012-01-01

    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. PMID:22745130

  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. 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.

  14. Information-Theoretic Approach May Shed a Light to a Better Understanding and Sustaining the Integrity of Ecological-Societal Systems under Changing Climate

    NASA Astrophysics Data System (ADS)

    Kim, J.

    2016-12-01

    Considering high levels of uncertainty, epistemological conflicts over facts and values, and a sense of urgency, normal paradigm-driven science will be insufficient to mobilize people and nation toward sustainability. The conceptual framework to bridge the societal system dynamics with that of natural ecosystems in which humanity operates remains deficient. The key to understanding their coevolution is to understand `self-organization.' Information-theoretic approach may shed a light to provide a potential framework which enables not only to bridge human and nature but also to generate useful knowledge for understanding and sustaining the integrity of ecological-societal systems. How can information theory help understand the interface between ecological systems and social systems? How to delineate self-organizing processes and ensure them to fulfil sustainability? How to evaluate the flow of information from data through models to decision-makers? These are the core questions posed by sustainability science in which visioneering (i.e., the engineering of vision) is an essential framework. Yet, visioneering has neither quantitative measure nor information theoretic framework to work with and teach. This presentation is an attempt to accommodate the framework of self-organizing hierarchical open systems with visioneering into a common information-theoretic framework. A case study is presented with the UN/FAO's communal vision of climate-smart agriculture (CSA) which pursues a trilemma of efficiency, mitigation, and resilience. Challenges of delineating and facilitating self-organizing systems are discussed using transdisciplinary toold such as complex systems thinking, dynamic process network analysis and multi-agent systems modeling. Acknowledgments: This study was supported by the Korea Meteorological Administration Research and Development Program under Grant KMA-2012-0001-A (WISE project).

  15. EXPOSURE MODELING - SHEDS

    EPA Science Inventory

    This presentation provides a general overview of SHEDS model features, describes algorithms in the SHEDS-Air Toxics model that focus on mobile source exposures and multipathway exposures, and presents examples of results from application of the SHEDS-Air Toxics model to benzene i...

  16. Cellular Transport and Bioactivity of a Major Saffron Apocarotenoid, Picrocrocin (4-(β-D-Glucopyranosyloxy)-2,6,6-trimethyl-1-cyclohexene-1-carboxaldehyde).

    PubMed

    Kyriakoudi, Anastasia; O'Callaghan, Yvonne C; Galvin, Karen; Tsimidou, Maria Z; O'Brien, Nora M

    2015-10-07

    The cellular transport and bioactivity of the second major saffron apocarotenoid, picrocrocin, was examined in parallel to that of the major group, crocetin sugar esters, in aqueous extracts. The transport of pure picrocrocin was investigated in comparison to that of other saffron apocarotenoids, trans-crocetin (di-β-D-gentiobiosyl) ester and crocetin using the Caco-2 cell model coupled with an in vitro digestion procedure. RP-HPLC-DAD was employed to quantify the bioaccessible and bioavailable amounts of individual apocarotenoids. Picrocrocin and crocetin sugar esters though highly bioaccessible (75% and 60%, respectively) were transported at minute quantities (0.2% and 0.5%, respectively; 10-fold lower than crocetin). Picrocrocin did not protect against oxidant-induced DNA damage in U937, human monocytic blood cells at the concentration investigated, however, it reduced the proliferation of human adenocarcinoma and hepatocarcinoma cells. Our findings may be useful for the requirements of food legislation regarding saffron preparations, in which both apocarotenoid groups coexist.

  17. 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

  18. 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

  19. Control of rod shedding in the frog retina.

    PubMed

    Basinger, S F; Hollyfield, J G

    1980-01-01

    In all vertebrate species examined thus far, rod outer segment shedding follows a cyclic pattern in which the outer segment tips are shed shortly after the onset of light. Work in the rat retina suggests that rod shedding may follow a circadian rhythm which is controlled by one or more circadian oscillators. Our results in the frog retina are significantly different in that: rod shedding can be driven by the onset of light or other environmental cues; shedding does not persist in constant darkness; shedding is unaffected in frogs with chronic unilateral or bilateral optic nerve section; and shedding will rapidly phase shift to the time of light onset on a wide variety of diurnal cycles. Thus, rod shedding in the frog retina does not appear to be a classical circadian rhythm.

  20. SlCCD7 controls strigolactone biosynthesis, shoot branching and mycorrhiza-induced apocarotenoid formation in tomato.

    PubMed

    Vogel, Jonathan T; Walter, Michael H; Giavalisco, Patrick; Lytovchenko, Anna; Kohlen, Wouter; Charnikhova, Tatsiana; Simkin, Andrew J; Goulet, Charles; Strack, Dieter; Bouwmeester, Harro J; Fernie, Alisdair R; Klee, Harry J

    2010-01-01

    The regulation of shoot branching is an essential determinant of plant architecture, integrating multiple external and internal signals. One of the signaling pathways regulating branching involves the MAX (more axillary branches) genes. Two of the genes within this pathway, MAX3/CCD7 and MAX4/CCD8, encode carotenoid cleavage enzymes involved in generating a branch-inhibiting hormone, recently identified as strigolactone. Here, we report the cloning of SlCCD7 from tomato. As in other species, SlCCD7 encodes an enzyme capable of cleaving cyclic and acyclic carotenoids. However, the SlCCD7 protein has 30 additional amino acids of unknown function at its C terminus. Tomato plants expressing a SlCCD7 antisense construct display greatly increased branching. To reveal the underlying changes of this strong physiological phenotype, a metabolomic screen was conducted. With the exception of a reduction of stem amino acid content in the transgenic lines, no major changes were observed. In contrast, targeted analysis of the same plants revealed significantly decreased levels of strigolactone. There were no significant changes in root carotenoids, indicating that relatively little substrate is required to produce the bioactive strigolactones. The germination rate of Orobanche ramosa seeds was reduced by up to 90% on application of extract from the SlCCD7 antisense lines, compared with the wild type. Additionally, upon mycorrhizal colonization, C(13) cyclohexenone and C(14) mycorradicin apocarotenoid levels were greatly reduced in the roots of the antisense lines, implicating SlCCD7 in their biosynthesis. This work demonstrates the diverse roles of MAX3/CCD7 in strigolactone production, shoot branching, source-sink interactions and production of arbuscular mycorrhiza-induced apocarotenoids.

  1. Selective Substrates and Inhibitors for Kallikrein-Related Peptidase 7 (KLK7) Shed Light on KLK Proteolytic Activity in the Stratum Corneum.

    PubMed

    de Veer, Simon J; Furio, Laetitia; Swedberg, Joakim E; Munro, Christopher A; Brattsand, Maria; Clements, Judith A; Hovnanian, Alain; Harris, Jonathan M

    2017-02-01

    Proteases have pivotal roles in the skin's outermost layer, the epidermis. In the stratum corneum, serine proteases from the kallikrein-related peptidase (KLK) family have been implicated in several key homeostatic processes, including desquamation. However, the precise contribution of specific KLKs to each process remains unclear. To address this, we used a chemical biology approach and designed selective substrates and inhibitors for KLK7, the most abundant KLK protease in the stratum corneum. The resulting KLK7 inhibitor is the most potent inhibitor of this protease reported to date (Ki = 140 pM), and displays at least 1,000-fold selectivity over several proteases that are related by function (KLK5 and KLK14) or specificity (chymotrypsin). We then used substrates and inhibitors for KLK5, KLK7, and KLK14 to explore the activity of each protease in the stratum corneum using casein zymography and an ex vivo desquamation assay. These experiments provide the most detailed assessment of each KLK's contribution to corneocyte shedding in the plantar stratum corneum, revealing that inhibition of KLK7 alone is sufficient to block shedding, whereas KLK5 is also a major contributor. Collectively, these findings unveil chemical tools for studying KLK activity and demonstrate their potential for characterizing KLK biological functions in epidermal homeostasis. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  2. 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. .

  3. View from underneath umbrella shed at rear of Train Shed ...

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

    View from underneath umbrella shed at rear of Train Shed looking W. - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  4. Local load shedding

    SciTech Connect

    Adibi, M.M.; Thorne, D.K. )

    1988-08-01

    Equipment overloads in an underground transmission network are caused by unscheduled outages. Repairs or replacements of damaged cables and/or transformers in urban areas are inherently difficult and time-consuming. Therefore, for overloads greatly in excess of short-time ratings, speed of load shedding is of paramount importance. Under such conditions, the system operator is faced with: recognizing the problem, determining the course of action and shedding the correct amount of load at the right locations. These tasks are difficult to perform, particularly under pressure of time. Reliance on pre-specified load shedding lists is not satisfactory since the load shedding lists do not necessarily match the amounts and locations of the required loads to be shed. Clearly, there has been a need for a local load shedding scheme, which in the first order of importance, would relieve the overloaded equipment within the time limits imposed by the equipment short-time ratings and in the second order of importance, would ''minimize'' the amount of load to be curtailed. This paper describes an approach which meets the dual objective, providing a practical solution to a difficult engineering/operating problem.

  5. 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

  6. Shedding Light on the 2016 World Health Organization Classification of Tumors of the Central Nervous System in the Era of Radiomics and Radiogenomics.

    PubMed

    Colen, Rivka R; Hassan, Islam; Elshafeey, Nabil; Zinn, Pascal O

    2016-11-01

    The new World Health Organization classification of brain tumors depends on combining the histologic light microscopy features of central nervous system (CNS) tumors with canonical genetic alterations. This integrated diagnosis is redrawing the pedigree chart of brain tumors with rearrangement of tumor groups on the basis of geno-phenotypical behaviors into meaningful groups. Multiple radiogenomic studies provide a bridge between imaging features and tumor microenvironment. An overlap that can be integrated within the genophenotypical classification of CNS tumors for a better understanding of different clinically relevant entities. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. 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

  8. 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

  9. Kepler sheds new and unprecedented light on the variability of a blue supergiant: Gravity waves in the O9.5Iab star HD 188209

    NASA Astrophysics Data System (ADS)

    Aerts, C.; Símon-Díaz, S.; Bloemen, S.; Debosscher, J.; Pápics, P. I.; Bryson, S.; Still, M.; Moravveji, E.; Williamson, M. H.; Grundahl, F.; Fredslund Andersen, M.; Antoci, V.; Pallé, P. L.; Christensen-Dalsgaard, J.; Rogers, T. M.

    2017-06-01

    Stellar evolution models are most uncertain for evolved massive stars. Asteroseismology based on high-precision uninterrupted space photometry has become a new way to test the outcome of stellar evolution theory and was recently applied to a multitude of stars, but not yet to massive evolved supergiants.Our aim is to detect, analyse and interpret the photospheric and wind variability of the O9.5 Iab star HD 188209 from Kepler space photometry and long-term high-resolution spectroscopy. We used Kepler scattered-light photometry obtained by the nominal mission during 1460 d to deduce the photometric variability of this O-type supergiant. In addition, we assembled and analysed high-resolution high signal-to-noise spectroscopy taken with four spectrographs during some 1800 d to interpret the temporal spectroscopic variability of the star. The variability of this blue supergiant derived from the scattered-light space photometry is in full in agreement with the one found in the ground-based spectroscopy. We find significant low-frequency variability that is consistently detected in all spectral lines of HD 188209. The photospheric variability propagates into the wind, where it has similar frequencies but slightly higher amplitudes. The morphology of the frequency spectra derived from the long-term photometry and spectroscopy points towards a spectrum of travelling waves with frequency values in the range expected for an evolved O-type star. Convectively-driven internal gravity waves excited in the stellar interior offer the most plausible explanation of the detected variability. Based on photometric observations made with the NASA Kepler satellite and on spectroscopic observations made with four telescopes: the Nordic Optical Telescope operated by NOTSA and the Mercator Telescope operated by the Flemish Community, both at the Observatorio del Roque de los Muchachos (La Palma, Spain) of the Instituto de Astrofísica de Canarias, the T13 2.0 m Automatic Spectroscopic

  10. Molecular and phylogenetic analyses reveal mammalian-like clockwork in the honey bee (Apis mellifera) and shed new light on the molecular evolution of the circadian clock.

    PubMed

    Rubin, Elad B; Shemesh, Yair; Cohen, Mira; Elgavish, Sharona; Robertson, Hugh M; Bloch, Guy

    2006-11-01

    The circadian clock of the honey bee is implicated in ecologically relevant complex behaviors. These include time sensing, time-compensated sun-compass navigation, and social behaviors such as coordination of activity, dance language communication, and division of labor. The molecular underpinnings of the bee circadian clock are largely unknown. We show that clock gene structure and expression pattern in the honey bee are more similar to the mouse than to Drosophila. The honey bee genome does not encode an ortholog of Drosophila Timeless (Tim1), has only the mammalian type Cryptochrome (Cry-m), and has a single ortholog for each of the other canonical "clock genes." In foragers that typically have strong circadian rhythms, brain mRNA levels of amCry, but not amTim as in Drosophila, consistently oscillate with strong amplitude and a phase similar to amPeriod (amPer) under both light-dark and constant darkness illumination regimes. In contrast to Drosophila, the honey bee amCYC protein contains a transactivation domain and its brain transcript levels oscillate at virtually an anti-phase to amPer, as it does in the mouse. Phylogenetic analyses indicate that the basal insect lineage had both the mammalian and Drosophila types of Cry and Tim. Our results suggest that during evolution, Drosophila diverged from the ancestral insect clock and specialized in using a set of clock gene orthologs that was lost by both mammals and bees, which in turn converged and specialized in the other set. These findings illustrate a previously unappreciated diversity of insect clockwork and raise critical questions concerning the evolution and functional significance of species-specific variation in molecular clockwork.

  11. CAF-like state in primary skin fibroblasts with constitutional BRCA1 epimutation sheds new light on tumor suppressor deficiency-related changes in healthy tissue

    PubMed Central

    Etzold, Anna; Galetzka, Danuta; Weis, Eva; Bartsch, Oliver; Haaf, Thomas; Spix, Claudia; Itzel, Timo; Schweiger, Susann; Strand, Dennis; Strand, Susanne; Zechner, Ulrich

    2016-01-01

    ABSTRACT Constitutive epimutations of tumor suppressor genes are increasingly considered as cancer predisposing factors equally to sequence mutations. In light of the emerging role of the microenvironment for cancer predisposition, initiation, and progression, we aimed to characterize the consequences of a BRCA1 epimutation in cells of mesenchymal origin. We performed a comprehensive molecular and cellular comparison of primary dermal fibroblasts taken from a monozygous twin pair discordant for recurrent cancers and BRCA1 epimutation, whose exceptional clinical case we previously reported in this journal. Comparative transcriptome analysis identified differential expression of extracellular matrix-related genes and pro-tumorigenic growth factors, such as collagens and CXC chemokines. Moreover, genes known to be key markers of so called cancer-associated fibroblasts (CAFs), such as ACTA2, FAP, PDPN, and TNC, were upregulated in fibroblasts of the affected twin (BRCA1mosMe) in comparison to those of the healthy twin (BRCA1wt). Further analyses detected CAF-typical cellular features, including an elevated growth rate, enhanced migration, altered actin architecture and increased production of ketone bodies in BRCA1mosMe fibroblasts compared to BRCA1wt fibroblasts. In addition, conditioned medium of BRCA1mosMe fibroblasts was more potent than conditioned medium of BRCA1wt fibroblasts to promote cell proliferation in an epithelial and a cancer cell line. Our data demonstrate, that a CAF-like state is not an exclusive feature of tumor-associated tissue but also exists in healthy tissue with tumor suppressor deficiency. The naturally occurring phenomenon of twin fibroblasts differing in their BRCA1 methylation status revealed to be a unique powerful tool for exploring tumor suppressor deficiency-related changes in healthy tissue, reinforcing their significance for cancer predisposition. PMID:26949839

  12. 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

  13. Tomato carotenoid cleavage dioxygenases 1A and 1B: Relaxed double bond specificity leads to a plenitude of dialdehydes, mono-apocarotenoids and isoprenoid volatiles

    PubMed Central

    Ilg, Andrea; Bruno, Mark; Beyer, Peter; Al-Babili, Salim

    2014-01-01

    The biosynthetic processes leading to many of the isoprenoid volatiles released by tomato fruits are still unknown, though previous reports suggested a clear correlation with the carotenoids contained within the fruit. In this study, we investigated the activity of the tomato (Solanum lycopersicum) carotenoid cleavage dioxygenase (SlCCD1B), which is highly expressed in fruits, and of its homolog SlCCD1A. Using in vitro assays performed with purified recombinant enzymes and by analyzing products formed by the two enzymes in carotene-accumulating Escherichia coli strains, we demonstrate that SlCCD1A and, to a larger extent, SlCCD1B, have a very relaxed specificity for both substrate and cleavage site, mediating the oxidative cleavage of cis- and all-trans-carotenoids as well as of different apocarotenoids at many more double bonds than previously reported. This activity gives rise to a plenitude of volatiles, mono-apocarotenoids and dialdehyde products, including cis-pseudoionone, neral, geranial, and farnesylacetone. Our results provide a direct evidence for a carotenoid origin of these compounds and point to CCD1s as the enzymes catalyzing the formation of the vast majority of tomato isoprenoid volatiles, many of which are aroma constituents. PMID:25057464

  14. 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.

  15. Clinical Trials Shed Light on Minority Health

    MedlinePlus

    ... Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products For Consumers Home For Consumers ... Info You Need More in Consumer Updates Animal & Veterinary Children's Health Cosmetics Dietary Supplements Drugs Food Medical ...

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  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. Shedding light on pilot-wave phenomena

    NASA Astrophysics Data System (ADS)

    Brun, P.-T.; Harris, Daniel M.; Prost, Victor; Quintela, Julio; Bush, John W. M.

    2016-09-01

    This paper is associated with a video winner of a 2015 APS/DFD Gallery of Fluid Motion Award. The original video is available from the Gallery of Fluid Motion, http://dx.doi.org/10.1103/APS.DFD.2015.GFM.V0064

  2. 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

  3. Shedding light on insight: Priming bright ideas.

    PubMed

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

    2010-07-01

    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.

  4. 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.

  5. Shedding New Light on Diversity Training.

    ERIC Educational Resources Information Center

    Johnson, Ronita B.; O'Mara, Julie

    1992-01-01

    The challenge at Pacific Gas & Electric was to train 27,000 employees to create an environment in which cultural diversity improves the company's competitive advantage. The solution was to train and certify 110 employees as diversity awareness trainers. (JOW)

  6. 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

  7. 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.

  8. Research sheds light on lymph node mystery.

    PubMed

    1996-01-01

    Researchers explain why so much HIV is found in the lymph nodes. The follicular dendritic cells act like flypaper to HIV and other pathogens. Once attracted, HIV is able to ambush critical immune cells, even in the presence of a vast excess of neutralizing antibodies. In the absence of follicular dendritic cells, similar quantities of neutralizing antibodies block HIV infectivity.

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  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. 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

  16. 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.

  17. Photoreceptor disc shedding in the living human eye

    PubMed Central

    Kocaoglu, Omer P.; Liu, Zhuolin; Zhang, Furu; Kurokawa, Kazuhiro; Jonnal, Ravi S.; Miller, Donald T.

    2016-01-01

    Cone photoreceptors undergo a daily cycle of renewal and shedding of membranous discs in their outer segments (OS), the portion responsible for light capture. These physiological processes are fundamental to maintaining photoreceptor health, and their dysfunction is associated with numerous retinal diseases. While both processes have been extensively studied in animal models and postmortem eyes, little is known about them in the living eye, in particular human. In this study, we report discovery of the optical signature associated with disc shedding using a method based on adaptive optics optical coherence tomography (AO-OCT) in conjunction with post-processing methods to track and monitor individual cone cells in 4D. The optical signature of disc shedding is characterized by an abrupt transient loss in the cone outer segment tip (COST) reflection followed by its return that is axially displaced anteriorly. Using this signature, we measured the temporal and spatial properties of shedding events in three normal subjects. Average duration of the shedding event was 8.8 ± 13.4 minutes, and average length loss of the OS was 2.1 μm (7.0% of OS length). Prevalence of cone shedding was highest in the morning (14.3%) followed by the afternoon (5.7%) and evening (4.0%), with load distributed across the imaged patch. To the best of our knowledge these are the first images of photoreceptor disc shedding in the living retina. PMID:27895995

  18. View Shed - Version 1.0

    SciTech Connect

    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.

  19. 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.

  20. 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

  1. SHEDS-Dietary Technical Manual Appendices

    EPA Pesticide Factsheets

    The appendices for the SHEDS-Dietary Technical Manual include a sample food diary, backgorund information on the water concentration data used in SHEDS-Dietary, a food list, food definitions and sample code.

  2. Low flow vortex shedding flowmeter

    NASA Technical Reports Server (NTRS)

    Waugaman, Charles J.

    1989-01-01

    The purpose was to continue a development project on a no moving parts vortex shedding flowmeter used for flow measurement of hypergols. The project involved the design and construction of a test loop to evaluate the meter for flow of Freon which simulates the hypergol fluids. Results were obtained on the output frequency characteristics of the flow meter as a function of flow rate. A family of flow meters for larger size lines and ranges of flow was sized based on the results of the tested meter.

  3. In-chain neutral hydrocarbon loss from crocin apocarotenoid ester glycosides and the crocetin aglycon (Crocus sativus L.) by ESI-MS(n) (n=2, 3).

    PubMed

    Pittenauer, Ernst; Koulakiotis, Nikolaos Stavros; Tsarbopoulos, Anthony; Allmaier, Guenter

    2013-12-01

    The stigmas of Crocus sativus L. have been used as spice and colorant agent (i.e. saffron) for more than 4000 years. For an updated structural investigation of the aglycon present in the glycosylated crocetin apocarotenoids (i.e. crocins), seven representative derivatives ranging from one up to five glucosyl-residues with a maximum number of three monosaccharides per glycosylation site (glucose, gentiobiose, gentiotriose and neapolitanose) were isolated and purified by high-performance liquid chromatography. The compounds selected for further mass spectrometric investigation include glucosyl-, bis-glucosyl-, gentiobiosyl-, gentiobiosyl-glucosyl-, bis-gentiobiosyl-, gentiobiosyl-gentiotriosyl- and gentiobiosyl-neapolitanosyl-crocetin. Electrospray ionization in combination with low-energy collision-induced dissociation/tandem mass spectrometry of sodiated crocin precursor ions utilizing either a 3D-ion trap (MS(n) , n = 2, 3) or a QqTOF instrument, with the latter providing accurate mass determination with an accuracy of ±1-3 ppm or better at a resolution of 10,000 (full width at half maximum), was used. Major fragmentation pathways included loss of either one or two carbohydrate substituents leading to the sodiated aglycon without interglycosidic bond cleavage during in MS(2) -experiments. All sodiated precursor ions and major product ions were accompanied by a loss of 92 Da, which was elucidated as C7 H8 -loss from the aglycon by skeletal rearrangement via an eight-membered transition state as previously described for intact C40-carotenoids.

  4. Phenomenon of Alfvenic Vortex Shedding

    SciTech Connect

    Gruszecki, M.; Nakariakov, V. M.; Van Doorsselaere, T.; Arber, T. D.

    2010-07-30

    Generation of Alfvenic (magnetohydrodynamic) vortices by the interaction of compressible plasma flows with magnetic-field-aligned blunt obstacles is modeled in terms of magnetohydrodynamics. It is found that periodic shedding of vortices with opposite vorticity is a robust feature of the interaction in a broad range of plasma parameters: for plasma beta from 0.025 to 0.5, and for the flow speeds from 0.1 to 0.99 of the fast magnetoacoustic speed. The Strouhal number is the dimensionless ratio of the blunt body diameter to the product of the period of vortex shedding and the inflow speed. It is found to be consistently in the range 0.15-0.25 in the whole range of parameters. The induced Alfvenic vortices are compressible and contain spiral-armed perturbations of the magnetic field strength and plasma mass density up to 50%-60% of the background values. The generated electric current also has the spiral-armed structuring.

  5. 77 FR 53884 - Automatic Underfrequency Load Shedding and Load Shedding Plans Reliability Standards; Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-04

    ... Energy Regulatory Commission Automatic Underfrequency Load Shedding and Load Shedding Plans Reliability...\\ Automatic Underfrequency Load Shedding and Load Shedding Plans Reliability Standards, 139 FERC ] 61,098... 20426. This filing is accessible on-line at http://www.ferc.gov , using the ``eLibrary'' link and...

  6. 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.

  7. Light

    NASA Astrophysics Data System (ADS)

    Vernon, C. G.

    2016-09-01

    Preface; 1. Historical; 2. Waves and wave-motion; 3. The behaviour of ripples; 4. The behaviour of light; 5. Refraction through glass blocks and prisms; 6. The imprinting of curvatures; 7. Simple mathematical treatment; 8. More advanced mathematical treatment; 9. The velocity of light; 10. The spectrum and colour; 11. Geometrical optics; 12. The eye and optical instruments; 13. Sources of light; 14. Interference, diffraction and polarisation; 15. Suggestions for class experiments; Index.

  8. Prevalence of hair shedding among women.

    PubMed

    Kovacevic, Maja; Goren, Andy; Shapiro, Jerry; Sinclair, Rodney; Lonky, Neal M; Situm, Mirna; Bulat, Vedrana; Bolanca, Zeljana; McCoy, John

    2017-01-01

    Hair shedding in female patients is a frequent complaint in dermatological, endocrinological, and gynecological consults. Previously, the Sinclair Hair Shedding Scale was developed to assess normal versus excessive hair shedding in female pattern hair loss (FPHL) subjects. However, the prevalence of hair shedding in females not suffering from FPHL is unknown. To gain better understanding of hair shedding in the general population, we recruited 300 subjects visiting a public hospital for conditions other than alopecia. Of the 300 subjects recruited, 263 did not suffer from FPHL. Among those subjects, approximately 40% reported experiencing excessive hair shedding (as defined by the Sinclair Hair Shedding Scale) on hair washing days. In comparison, in our subject population, approximately 60% of subjects with FPHL reported excessive hair shedding on hair washing days. To best of our knowledge, this is the first study to quantify the prevalence of hair shedding in women. While, no treatment currently exists for this condition, we hope that this study would encourage physicians and researchers to address this frequent concern.

  9. Shedding patterns of Daubaylia potomaca (Nematoda: Rhabditida).

    PubMed

    Zimmermann, Michael R; Luth, Kyle E; Esch, Gerald W

    2013-12-01

    Daubaylia potomaca is a nematode parasite that exhibits an unusual direct life cycle in planorbid snails in which adult females are the infective stage, after being shed from a definitive host. The present study examined the shedding patterns of this nematode to determine what cues or mechanisms might lead to the parasite leaving its host. A correlation was found between host death and the frequency and number of D. potomaca shed, suggesting that the nematodes can detect that the host is dying and may leave in search of a new host. Furthermore, elevated intensities of D. potomaca in the snail induce shedding earlier, suggesting that competition for space and resources may also play a role in the shedding patterns of the nematode, but not when time to death is controlled. Finally, nematodes shed a longer time before host death were significantly longer and more likely to be gravid than those shed as time to snail death approached, implying that the nematode reaching maturity or being inseminated might also be cues for D. potomaca to leave its snail host. In summary, the shedding patterns of D. potomaca appear to be a complex mix of host death detection, competition, and nematode maturation.

  10. 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

  11. Thermodynamics of Binding of Structurally Similar Ligands to Histone Deacetylase 8 Sheds Light on Challenges in the Rational Design of Potent and Isozyme-Selective Inhibitors of the Enzyme

    PubMed Central

    2015-01-01

    Among the different histone deacetylase (HDAC) isozymes, HDAC8 is the most highly malleable enzyme, and it exhibits the potential to accommodate structurally diverse ligands (albeit with moderate binding affinities) in its active site pocket. To probe the molecular basis of this feature, we performed detailed thermodynamic studies of the binding of structurally similar ligands, which differed with respect to the “cap”, “linker”, and “metal-binding” regions of the suberoylanilide hydroxamic acid (SAHA) pharmacophore, to HDAC8. The experimental data revealed that although the enthalpic (ΔH°) and entropic (ΔS°) changes for the binding of individual SAHA analogues to HDAC8 were substantially different, their binding free energies (ΔG°) were markedly similar, conforming to a strong enthalpy–entropy compensation effect. This effect was further observed in the temperature-dependent thermodynamics of binding of all SAHA analogues to the enzyme. Notably, in contrast to other metalloenzymes, our isothermal titration calorimetry experiments (performed in different buffers of varying ionization enthalpies) suggest that depending on the ligand, its zinc-binding group may or may not be deprotonated upon the binding to HDAC8. Furthermore, the heat capacity changes (ΔCp°) associated with the ligand binding to HDAC8 markedly differed from one SAHA analogue to the other, and such features could primarily be rationalized in light of the dynamic flexibility in the enzyme structure in conjunction with the reorganization of the active site resident water molecules. Arguments are presented that although the binding thermodynamic features described above would facilitate identification of weak to moderately tight-binding HDAC8 inhibitors (by a high-throughput and/or virtual screening of libraries of small molecules), they would pose major challenges for the structure-based rational design of highly potent and isozyme-selective inhibitors of human HDAC8. PMID:25407689

  12. Knock-down of the MEP pathway isogene 1-deoxy-D-xylulose 5-phosphate synthase 2 inhibits formation of arbuscular mycorrhiza-induced apocarotenoids, and abolishes normal expression of mycorrhiza-specific plant marker genes.

    PubMed

    Floss, Daniela S; Hause, Bettina; Lange, Peter R; Küster, Helge; Strack, Dieter; Walter, Michael H

    2008-10-01

    The first step of the plastidial methylerythritol phosphate (MEP) pathway is catalyzed by two isoforms of 1-deoxy-D-xylulose 5-phosphate synthase (DXS1 and DXS2). In Medicago truncatula, MtDXS1 and MtDXS2 genes exhibit completely different expression patterns. Most prominently, colonization by arbuscular mycorrhizal (AM) fungi induces the accumulation of certain apocarotenoids (cyclohexenone and mycorradicin derivatives) correlated with the expression of MtDXS2 but not of MtDXS1. To prove a distinct function of DXS2, a selective RNAi approach on MtDXS2 expression was performed in transgenic hairy roots of M. truncatula. Repression of MtDXS2 consistently led to reduced transcript levels in mycorrhizal roots, and to a concomitant reduction of AM-induced apocarotenoid accumulation. The transcript levels of MtDXS1 remained unaltered in RNAi plants, and no phenotypical changes in non-AM plants were observed. Late stages of the AM symbiosis were adversely affected, but only upon strong repression with residual MtDXS2-1 transcript levels remaining below approximately 10%. This condition resulted in a strong decrease in the transcript levels of MtPT4, an AM-specific plant phosphate transporter gene, and in a multitude of other AM-induced plant marker genes, as shown by transcriptome analysis. This was accompanied by an increased proportion of degenerating and dead arbuscules at the expense of mature ones. The data reveal a requirement for DXS2-dependent MEP pathway-based isoprenoid products to sustain mycorrhizal functionality at later stages of the symbiosis. They further validate the concept of a distinct role for DXS2 in secondary metabolism, and offer a novel tool to selectively manipulate the levels of secondary isoprenoids by targeting their precursor supply.

  13. Non-imaging Characterization Assessment of Shedding Events from Derelict Satellites near Geosynchronous Orbit (GEO)

    NASA Astrophysics Data System (ADS)

    Kelecy, T.; Skinner, M.

    2016-09-01

    There is plausible speculation that retired satellites near geosynchronous orbit are the source of a debris population that was passively shed over time due to environmental effects. Recent initiatives intended to characterize these defunct satellites via analysis of non-imaging observations have established the ability to derive some of their physical and dynamic attributes. For long term observing of objects, what kinds of changes might one be able to detect that might be attributed to shedding? Are there any attributes common to both the shed piece of debris and the parent object that might allow one to tie the two together? The work presented attempts to shed some light on these questions by establishing several plausible shedding scenarios which include appropriate dynamics, shapes and materials, and uses appropriate bi-directional reflectance distribution functions and Long Wave Infrared (LWIR) models to create a simulated time history of observations that can be examined to analyze the shedding phenomenon. The goal of this work is to provide some insight into what characterization changes one might attribute to shedding when observing a "parent" object over an extended period. The results show that astrometric, photometric, albedo-area product, and multi-wavelength brightness observations each provide unique characterization attributes which, when combined, allow one to infer shedding phenomena.

  14. 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.

  15. Causes of failure of airship shed

    NASA Technical Reports Server (NTRS)

    Sonntag, R; Hoff, W

    1922-01-01

    The causes of the collapse of airship shed, which was being taken down at Niediergorsdorf, are discussed. This shed, which was built of iron, was 184 m long, 28 m high, and 35 m wide. The demolition of the shed had been assigned to unskilled men who proceeded to remove certain key structural supports, leaving the structure in such a condition that relatively small eccentricities of the columns or spans or of lateral forces could easily have caused the columns or spans to break down. A small gust of wind would have perhaps sufficed to bring the building down. An analysis is also given of the suction effects on the roof of an air shed in Staaken. The damage to this shed, which occurred during a storm, was due to the fact that the shed had no opening in its top for equalizing the air pressure within and without. The location of the plates blown off the roof correspond to the point of greatest suction.

  16. Lighting

    SciTech Connect

    Audin, L.

    1994-12-31

    EPAct covers a vast territory beyond lighting and, like all legislation, also contains numerous {open_quotes}favors,{close_quotes} compromises, and even some sleight-of-hand. Tucked away under Title XIX, for example, is an increase from 20% to 28% tax on gambling winnings, effective January 1, 1993 - apparently as a way to help pay for new spending listed elsewhere in the bill. Overall, it is a landmark piece of legislation, about a decade overdue. It remains to be seen how the Federal Government will enforce upgrading of state (or even their own) energy codes. There is no mention of funding for {open_quotes}energy police{close_quotes} in EPAct. Merely creating such a national standard, however, provides a target for those who sincerely wish to create an energy-efficient future.

  17. 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.

  18. Principles of Food Science Class Sheds Light on Chemistry

    ERIC Educational Resources Information Center

    Ward, Janet

    2004-01-01

    Many students are curious about the steps in food preparation. As a result of such experiences, the author of this article began to incorporate science demonstrations into food preparation classes. She conducted research, developed resources, and piloted the "Principles of Food Science" class over the next 6 years. "Principles of Food Science"…

  19. Experiments shed new light on nickel-fluorine reactions

    NASA Technical Reports Server (NTRS)

    Fischer, J.; Gunther, W.; Jarry, R. L.

    1967-01-01

    Isotopic tracer experiments and scale-impingement experiments show fluorine to be the migrating species through the nickel fluoride scale formed during the fluorination of nickel. This is in contrast to nickel oxide scales, where nickel is the migrating species.

  20. Raman spectroscopy of natron: shedding light on ancient Egyptian mummification.

    PubMed

    Edwards, Howell G M; Currie, Katherine J; Ali, Hassan R H; Jorge Villar, Susana E; David, A Rosalie; Denton, John

    2007-06-01

    The mummification ritual in ancient Egypt involved the evisceration of the corpse and its desiccation using natron, a naturally occurring evaporitic mineral deposit from the Wadi Natrun, Egypt. The deposit typically contains sodium carbonate, sodium bicarbonate and impurities of chloride and sulfate as its major elemental components. It is believed that the function of the natron was to rapidly remove the water from the cadaver to prevent microbial attack associated with subsequent biological tissue degradation and putrefaction. Several specimens of natron that were recently collected from the Wadi Natrun contained coloured zones interspersed with the mineral matrix that are superficially reminiscent of extremophilic cyanobacterial colonisation found elsewhere in hot and cold deserts. Raman spectroscopy of these specimens using visible and near-infrared laser excitation has revealed not only the mineral composition of the natron, but also evidence for the presence of cyanobacterial colonies in several coloured zones observed in the mineral matrix. Key Raman biosignatures of carotenoids, scytonemin and chlorophyll have been identified.

  1. Shedding Light on Shingles: The Power of Prevention.

    PubMed

    Herman, Lawrence; Levin, Myron J; Rehm, Susan

    2016-10-01

    Shingles, or herpes zoster (HZ), is a common secondary infection caused by a reactivated varicella zoster virus (VZV). More than 95% of immunocompetent individuals aged at least 50 years are seropositive for VZV and are therefore at risk for developing HZ. Age-related increased incidence of HZ and its complications are thought to be related to the decline in cell-mediated immunity. Complications of HZ, which create a significant patient and economic burden, may be neurological, ophthalmological, dermatological, or visceral. HZ vaccination is essential for the prevention of HZ and its consequences. This CME activity reviews the clinical presentations and complications of HZ as well as discusses strategies for prevention (Online access: http://courses.elseviercme.com/shingles/626).

  2. Proteomics approaches shed new light on hibernation physiology.

    PubMed

    Grabek, Katharine R; Martin, Sandra L; Hindle, Allyson G

    2015-08-01

    The broad phylogenetic distribution and rapid phenotypic transitions of mammalian hibernators imply that hibernation is accomplished by differential expression of common genes. Traditional candidate gene approaches have thus far explained little of the molecular mechanisms underlying hibernation, likely due to (1) incomplete and imprecise sampling of a complex phenotype, and (2) the forming of hypotheses about which genes might be important based on studies of model organisms incapable of such dynamic physiology. Unbiased screening approaches, such as proteomics, offer an alternative means to discover the cellular underpinnings that permit successful hibernation and may reveal previously overlooked, important pathways. Here, we review the findings that have emerged from proteomics studies of hibernation. One striking feature is the stability of the proteome, especially across the extreme physiological shifts of torpor-arousal cycles during hibernation. This has led to subsequent investigations of the role of post-translational protein modifications in altering protein activity without energetically wasteful removal and rebuilding of protein pools. Another unexpected finding is the paucity of universal proteomic adjustments across organ systems in response to the extreme metabolic fluctuations despite the universality of their physiological challenges; rather each organ appears to respond in a unique, tissue-specific manner. Additional research is needed to extend and synthesize these results before it will be possible to address the whole body physiology of hibernation.

  3. Innovative Visualizations Shed Light on Avian Nocturnal Migration

    PubMed Central

    Farnsworth, Andrew; Aelterman, Bart; Alves, Jose A.; Azijn, Kevin; Bernstein, Garrett; Branco, Sérgio; Desmet, Peter; Dokter, Adriaan M.; Horton, Kyle; Kelling, Steve; Kelly, Jeffrey F.; Leijnse, Hidde; Rong, Jingjing; Sheldon, Daniel; Van den Broeck, Wouter; Van Den Meersche, Jan Klaas; Van Doren, Benjamin Mark; van Gasteren, Hans

    2016-01-01

    Globally, billions of flying animals undergo seasonal migrations, many of which occur at night. The temporal and spatial scales at which migrations occur and our inability to directly observe these nocturnal movements makes monitoring and characterizing this critical period in migratory animals’ life cycles difficult. Remote sensing, therefore, has played an important role in our understanding of large-scale nocturnal bird migrations. Weather surveillance radar networks in Europe and North America have great potential for long-term low-cost monitoring of bird migration at scales that have previously been impossible to achieve. Such long-term monitoring, however, poses a number of challenges for the ornithological and ecological communities: how does one take advantage of this vast data resource, integrate information across multiple sensors and large spatial and temporal scales, and visually represent the data for interpretation and dissemination, considering the dynamic nature of migration? We assembled an interdisciplinary team of ecologists, meteorologists, computer scientists, and graphic designers to develop two different flow visualizations, which are interactive and open source, in order to create novel representations of broad-front nocturnal bird migration to address a primary impediment to long-term, large-scale nocturnal migration monitoring. We have applied these visualization techniques to mass bird migration events recorded by two different weather surveillance radar networks covering regions in Europe and North America. These applications show the flexibility and portability of such an approach. The visualizations provide an intuitive representation of the scale and dynamics of these complex systems, are easily accessible for a broad interest group, and are biologically insightful. Additionally, they facilitate fundamental ecological research, conservation, mitigation of human–wildlife conflicts, improvement of meteorological products, and public outreach, education, and engagement. PMID:27557096

  4. CIA sheds new light on nuclear control in CIS

    SciTech Connect

    Lockwood, D.

    1993-03-01

    In a wide-ranging presentation to the Senate Governmental Affairs Committee February 24, 1993, newly installed CIA director James Woolsey and one of his senior aides provided a great deal of new information on nuclear weapons issues and how they are controlled in the former USSR. The main topics covered in the briefing are briefly discussed.

  5. How endogenous plant pararetroviruses shed light on Musa evolution.

    PubMed

    Duroy, Pierre-Olivier; Perrier, Xavier; Laboureau, Nathalie; Jacquemoud-Collet, Jean-Pierre; Iskra-Caruana, Marie-Line

    2016-04-01

    Banana genomes harbour numerous copies of viral sequences derived from banana streak viruses (BSVs) - dsDNA viruses belonging to the family Caulimoviridae.These viral integrants (eBSVs) are mostly defective, probably as a result of 'pseudogenization' driven by host genome evolution. However, some can give rise to infection by releasing a functional viral genome following abiotic stresses. These distinct infective eBSVs correspond to the three main widespread BSV species (BSOLV, BSGFV and BSIMV), fully described within the Musa balbisiana B genomes of the seedy diploid 'Pisang Klutuk Wulung' (PKW). We characterize eBSV distribution among a Musa sampling including seedy BB diploids and interspecific hybrids with Musa acuminate exhibiting different levels of ploidy for the B genome (ABB, AAB, AB). We used representative samples of the two areas of sympatry between M. acuminate and M. balbisiana species representing the native area of the most widely cultivated AAB cultivars (in India and in East Asia, ranging from the Philippines to New Guinea). Seventy-seven accessions were characterized using eBSV-related PCR markers and Southern hybridization approaches. We coded both sets of results to create a common dissimilarity matrix with which to interpret eBSV distribution. We propose a Musa phylogeny driven by the M. balbisiana genome based on a dendrogram resulting from a joint neighbour-joining analysis of the three BSV species, showing for the first time lineages between BB and ABB/AAB hybrids. eBSVs appear to be relevant phylogenetic markers that can illustrate theM. balbisiana phylogeography story. The theoretical implications of this study for further elucidation of the historical and geographical process of Musa domestication are numerous. Discovery of banana plants with B genome non-infective for eBSV opens the way to the introduction of new genitors in programmes of genetic banana improvement. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. How endogenous plant pararetroviruses shed light on Musa evolution

    PubMed Central

    Duroy, Pierre-Olivier; Perrier, Xavier; Laboureau, Nathalie; Jacquemoud-Collet, Jean-Pierre; Iskra-Caruana, Marie-Line

    2016-01-01

    Background and Aims Banana genomes harbour numerous copies of viral sequences derived from banana streak viruses (BSVs) – dsDNA viruses belonging to the family Caulimoviridae. These viral integrants (eBSVs) are mostly defective, probably as a result of ‘pseudogenization’ driven by host genome evolution. However, some can give rise to infection by releasing a functional viral genome following abiotic stresses. These distinct infective eBSVs correspond to the three main widespread BSV species (BSOLV, BSGFV and BSIMV), fully described within the Musa balbisiana B genomes of the seedy diploid ‘Pisang Klutuk Wulung’ (PKW). Methods We characterize eBSV distribution among a Musa sampling including seedy BB diploids and interspecific hybrids with Musa acuminata exhibiting different levels of ploidy for the B genome (ABB, AAB, AB). We used representative samples of the two areas of sympatry between M. acuminata and M. balbisiana species representing the native area of the most widely cultivated AAB cultivars (in India and in East Asia, ranging from the Philippines to New Guinea). Seventy-seven accessions were characterized using eBSV-related PCR markers and Southern hybridization approaches. We coded both sets of results to create a common dissimilarity matrix with which to interpret eBSV distribution. Key Results We propose a Musa phylogeny driven by the M. balbisiana genome based on a dendrogram resulting from a joint neighbour-joining analysis of the three BSV species, showing for the first time lineages between BB and ABB/AAB hybrids. eBSVs appear to be relevant phylogenetic markers that can illustrate the M. balbisiana phylogeography story. Conclusion The theoretical implications of this study for further elucidation of the historical and geographical process of Musa domestication are numerous. Discovery of banana plants with B genome non-infective for eBSV opens the way to the introduction of new genitors in programmes of genetic banana improvement. PMID:26971286

  7. Mutation directional selection sheds light on prion pathogenesis

    SciTech Connect

    Shen, Liang; Ji, Hong-Fang

    2011-07-01

    Highlights: {yields} Most pathogenic mutations possess strong directional selection, i.e., enhancing hydrophobicity or decreasing negative and increasing positive charge. {yields} Mutation-induced changes may strengthen the interactions between PrP and facilitating factors. {yields} The findings also have significant implications for exploring potential regions involved in the conformational transition from PrP{sup C} to PrP{sup Sc}. -- Abstract: As mutations in the PRNP gene account for human hereditary prion diseases (PrDs), it is crucial to elucidating how these mutations affect the central pathogenic conformational transition of normal cellular prion protein (PrP{sup C}) to abnormal scrapie isoform (PrP{sup Sc}). Many studies proposed that these pathogenic mutations may make PrP more susceptible to conformational change through altering its structure stability. By evaluating the most recent observations regarding pathogenic mutations, it was found that the pathogenic mutations do not exert a uniform effect on the thermodynamic stability of the human PrP's structure. Through analyzing the reported PrDs-related mutations, we found that 25 out of 27 mutations possess strong directional selection, i.e., enhancing hydrophobicity or decreasing negative and increasing positive charge. Based on the triggering role reported by previous studies of facilitating factors in PrP{sup C} conversion, e.g., lipid and polyanion, we proposed that the mutation-induced changes may strengthen the interaction between PrP and facilitating factors, which will accelerate PrP conversion and cause PrDs.

  8. New Australian sauropods shed light on Cretaceous dinosaur palaeobiogeography

    PubMed Central

    Poropat, Stephen F.; Mannion, Philip D.; Upchurch, Paul; Hocknull, Scott A.; Kear, Benjamin P.; Kundrát, Martin; Tischler, Travis R.; Sloan, Trish; Sinapius, George H. K.; Elliott, Judy A.; Elliott, David A.

    2016-01-01

    Australian dinosaurs have played a rare but controversial role in the debate surrounding the effect of Gondwanan break-up on Cretaceous dinosaur distribution. Major spatiotemporal gaps in the Gondwanan Cretaceous fossil record, coupled with taxon incompleteness, have hindered research on this effect, especially in Australia. Here we report on two new sauropod specimens from the early Late Cretaceous of Queensland, Australia, that have important implications for Cretaceous dinosaur palaeobiogeography. Savannasaurus elliottorum gen. et sp. nov. comprises one of the most complete Cretaceous sauropod skeletons ever found in Australia, whereas a new specimen of Diamantinasaurus matildae includes the first ever cranial remains of an Australian sauropod. The results of a new phylogenetic analysis, in which both Savannasaurus and Diamantinasaurus are recovered within Titanosauria, were used as the basis for a quantitative palaeobiogeographical analysis of macronarian sauropods. Titanosaurs achieved a worldwide distribution by at least 125 million years ago, suggesting that mid-Cretaceous Australian sauropods represent remnants of clades which were widespread during the Early Cretaceous. These lineages would have entered Australasia via dispersal from South America, presumably across Antarctica. High latitude sauropod dispersal might have been facilitated by Albian–Turonian warming that lifted a palaeoclimatic dispersal barrier between Antarctica and South America. PMID:27763598

  9. Principles of Food Science Class Sheds Light on Chemistry

    ERIC Educational Resources Information Center

    Ward, Janet

    2004-01-01

    Many students are curious about the steps in food preparation. As a result of such experiences, the author of this article began to incorporate science demonstrations into food preparation classes. She conducted research, developed resources, and piloted the "Principles of Food Science" class over the next 6 years. "Principles of Food Science"…

  10. Shed a Little Light: Eight Illuminating Axioms of Market Research.

    ERIC Educational Resources Information Center

    Ryan, G. Jeremiah

    1993-01-01

    Principles for college market research include (1) only ask relevant questions; (2) ask key questions often; (3) compare responses; (4) ask important questions of many people; (4) keep the research simple; (5) don't cut corners; (6) listen to the customer through focus groups and complaint systems; and (7) share the information with people who can…

  11. Genomic Dark Matter Sheds Light on EVI1-driven Leukemia

    PubMed Central

    Koche, Richard; Armstrong, Scott A.

    2014-01-01

    The orchestration of transcriptional programs depends on proper gene-enhancer pairing. While much remains to be learned about this process in normal development, two recent studies in Cell and Cancer Cell highlight how the genomic rearrangement of an enhancer plays a causal role in the onset of a leukemogenic program. PMID:24735919

  12. Innovative Visualizations Shed Light on Avian Nocturnal Migration.

    PubMed

    Shamoun-Baranes, Judy; Farnsworth, Andrew; Aelterman, Bart; Alves, Jose A; Azijn, Kevin; Bernstein, Garrett; Branco, Sérgio; Desmet, Peter; Dokter, Adriaan M; Horton, Kyle; Kelling, Steve; Kelly, Jeffrey F; Leijnse, Hidde; Rong, Jingjing; Sheldon, Daniel; Van den Broeck, Wouter; Van Den Meersche, Jan Klaas; Van Doren, Benjamin Mark; van Gasteren, Hans

    2016-01-01

    Globally, billions of flying animals undergo seasonal migrations, many of which occur at night. The temporal and spatial scales at which migrations occur and our inability to directly observe these nocturnal movements makes monitoring and characterizing this critical period in migratory animals' life cycles difficult. Remote sensing, therefore, has played an important role in our understanding of large-scale nocturnal bird migrations. Weather surveillance radar networks in Europe and North America have great potential for long-term low-cost monitoring of bird migration at scales that have previously been impossible to achieve. Such long-term monitoring, however, poses a number of challenges for the ornithological and ecological communities: how does one take advantage of this vast data resource, integrate information across multiple sensors and large spatial and temporal scales, and visually represent the data for interpretation and dissemination, considering the dynamic nature of migration? We assembled an interdisciplinary team of ecologists, meteorologists, computer scientists, and graphic designers to develop two different flow visualizations, which are interactive and open source, in order to create novel representations of broad-front nocturnal bird migration to address a primary impediment to long-term, large-scale nocturnal migration monitoring. We have applied these visualization techniques to mass bird migration events recorded by two different weather surveillance radar networks covering regions in Europe and North America. These applications show the flexibility and portability of such an approach. The visualizations provide an intuitive representation of the scale and dynamics of these complex systems, are easily accessible for a broad interest group, and are biologically insightful. Additionally, they facilitate fundamental ecological research, conservation, mitigation of human-wildlife conflicts, improvement of meteorological products, and public outreach, education, and engagement.

  13. Shed a Little Light: Eight Illuminating Axioms of Market Research.

    ERIC Educational Resources Information Center

    Ryan, G. Jeremiah

    1993-01-01

    Principles for college market research include (1) only ask relevant questions; (2) ask key questions often; (3) compare responses; (4) ask important questions of many people; (4) keep the research simple; (5) don't cut corners; (6) listen to the customer through focus groups and complaint systems; and (7) share the information with people who can…

  14. Shedding light on the growth of gold nanoshells.

    PubMed

    Sauerbeck, Christian; Haderlein, Michael; Schürer, Benedikt; Braunschweig, Björn; Peukert, Wolfgang; Klupp Taylor, Robin N

    2014-03-25

    Nanostructured particles containing noble metals can have highly tunable localized surface plasmon resonances and are therefore of particular interest for numerous applications. Nanoshells comprising a dielectric core and gold or silver shell are a widely researched systems because of the strong dependence of their optical properties on the ratio of core diameter to shell thickness. Although seeded-growth procedures have been developed to produce these particles, the many reported studies show significant variation in the nanoshell morphologies and hence optical properties. In order to establish processes that reproducibly synthesize nanoshells with high optical quality, it is necessary to develop techniques that monitor changes at the core particle surface during shell growth. For that purpose, we have carried out in situ nonlinear second-harmonic scattering (SHS) and linear vis-NIR extinction spectroscopy simultaneously during the seeded growth of gold nanoshells on silica core particles. Our SHS measurements show a striking variation in the nonlinear optical properties of the growing gold nanoshells. In comparison with linear optical measurements and with scanning electron microscopy (SEM) images made of gold nanoshells produced with varying shell completenesses, the SHS signal was observed to reach a peak intensity at a stage prior to shell closure. We attribute this high sensitivity of the SHS signal to the incomplete nanoshell surface morphology to the generation and subsequent degeneration of regions of electric field enhancement at gaps between isolated gold islands, which grow and coalesce. This conclusion is corroborated by finite-difference time-domain simulations of incomplete nanoshells. We suggest that the in situ analytical approach demonstrated here offers significant promise for future activities regarding the in-process optimization of the morphology and optical properties of metal nanoshells and other nanostructured plasmonic particles.

  15. Shedding light on the matter of Abell 781

    NASA Astrophysics Data System (ADS)

    Wittman, D.; Dawson, William; Benson, Bryant

    2014-02-01

    The galaxy cluster Abell 781 West has been viewed as a challenge to weak gravitational lensing mass calibration, as Cook & dell'Antonio found that the weak lensing signal-to-noise ratio in three independent sets of observations was consistently lower than expected from mass models based on X-ray and dynamical measurements. We correct some errors in statistical inference in Cook & dell'Antonio and show that their own results agree well with the dynamical mass and exhibit at most 2.2-2.9σ low compared to the X-ray mass, similar to the tension between the dynamical and X-ray masses. Replacing their simple magnitude cut with weights based on source photometric redshifts eliminates the tension between lensing and X-ray masses; in this case the weak lensing mass estimate is actually higher than, but still in agreement with, the dynamical estimate. A comparison of lensing analyses with and without photometric redshifts shows that a 1-2σ chance alignment of low-redshift sources lowers the signal-to-noise ratio observed by all previous studies which used magnitude cuts rather than photometric redshifts. The fluctuation is unexceptional, but appeared to be highly significant in Cook & dell'Antonio due to the errors in statistical interpretation.

  16. Shedding Light on Filovirus Infection with High-Content Imaging

    PubMed Central

    Pegoraro, Gianluca; Bavari, Sina; Panchal, Rekha G.

    2012-01-01

    Microscopy has been instrumental in the discovery and characterization of microorganisms. Major advances in high-throughput fluorescence microscopy and automated, high-content image analysis tools are paving the way to the systematic and quantitative study of the molecular properties of cellular systems, both at the population and at the single-cell level. High-Content Imaging (HCI) has been used to characterize host-virus interactions in genome-wide reverse genetic screens and to identify novel cellular factors implicated in the binding, entry, replication and egress of several pathogenic viruses. Here we present an overview of the most significant applications of HCI in the context of the cell biology of filovirus infection. HCI assays have been recently implemented to quantitatively study filoviruses in cell culture, employing either infectious viruses in a BSL-4 environment or surrogate genetic systems in a BSL-2 environment. These assays are becoming instrumental for small molecule and siRNA screens aimed at the discovery of both cellular therapeutic targets and of compounds with anti-viral properties. We discuss the current practical constraints limiting the implementation of high-throughput biology in a BSL-4 environment, and propose possible solutions to safely perform high-content, high-throughput filovirus infection assays. Finally, we discuss possible novel applications of HCI in the context of filovirus research with particular emphasis on the identification of possible cellular biomarkers of virus infection. PMID:23012631

  17. Shedding Light on Students' Technology Preferences: Implications for Academic Development

    ERIC Educational Resources Information Center

    Mirriahi, Negin; Alonzo, Dennis

    2015-01-01

    This study built on previous research in 2010 to determine changes to students' current use of and expectations for future integration of technologies in their learning experience. The findings reveal a continued trend of conservative technology use amongst students but with a growing demand for more integration of technologies for assessment and…

  18. Shedding light on the evolution of plasticity in natural populations.

    PubMed

    Hyma, Katie E; Caicedo, Ana L

    2011-09-01

    Plasticity allows for changes in phenotype in response to environmental cues, often facilitating local adaptation to seasonal environments. Phenotypic plasticity alone, however, may not always be sufficient to ensure adaptation to new localities. In particular, changing cues associated with shifting seasonal regimes may no longer induce appropriate phenotypic responses in new environments (Nicotra et al. 2010). Plastic responses must thus evolve to avoid being maladaptive. To date, the extent to which plastic responses can change and the genetic mechanisms by which this can happen have remained elusive. In this issue of Molecular Ecology, Blackman et al. (2011a) harness natural variation in flowering time among populations of the wild sunflower, Helianthus annuus, to demonstrate that plasticity has indeed evolved in this species. Remarkably, they are able to detect changes in gene expression that are associated with both a loss of plasticity and a reversal of the plastic response. These changes occur in two separate, but integrated, regulatory pathways controlling the transition to flowering, suggesting that complex regulatory networks that incorporate multiple environmental and developmental cues may facilitate the evolution of plastic responses. This study leverages knowledge from plant genetic models to provide a surprising level of insight into the evolution of an adaptive trait in a non-model species. Through discoveries of the roles of gene duplication and network modularity in the evolution of plastic responses, the study raises questions about the degree to which species-specific network architectures may act as a constraint to the potential of adaptation. © 2011 Blackwell Publishing Ltd.

  19. Shedding light on the 'dark side' of phylogenetic comparative methods.

    PubMed

    Cooper, Natalie; Thomas, Gavin H; FitzJohn, Richard G

    2016-06-01

    Phylogenetic comparative methods are becoming increasingly popular for investigating evolutionary patterns and processes. However, these methods are not infallible - they suffer from biases and make assumptions like all other statistical methods.Unfortunately, although these limitations are generally well known in the phylogenetic comparative methods community, they are often inadequately assessed in empirical studies leading to misinterpreted results and poor model fits. Here, we explore reasons for the communication gap dividing those developing new methods and those using them.We suggest that some important pieces of information are missing from the literature and that others are difficult to extract from long, technical papers. We also highlight problems with users jumping straight into software implementations of methods (e.g. in r) that may lack documentation on biases and assumptions that are mentioned in the original papers.To help solve these problems, we make a number of suggestions including providing blog posts or videos to explain new methods in less technical terms, encouraging reproducibility and code sharing, making wiki-style pages summarising the literature on popular methods, more careful consideration and testing of whether a method is appropriate for a given question/data set, increased collaboration, and a shift from publishing purely novel methods to publishing improvements to existing methods and ways of detecting biases or testing model fit. Many of these points are applicable across methods in ecology and evolution, not just phylogenetic comparative methods.

  20. Subsurface Images Shed Light on Past Tsunamis in India

    NASA Astrophysics Data System (ADS)

    Nair, Rajesh R.; Buynevich, Ilya; Goble, Ronald J.; Srinivasan, P.; Murthy, S. G. N.; Kandpal, S. C.; Lakshmi, C. S. Vijaya; Trivedi, D.

    2010-12-01

    The 2004 Indian Ocean tsunami caused massive devastation and left a lasting impact along many of the major coastal regions in South Asia, including the coast of Tamil Nadu, a state in the southeastern tip of India. Following the event, sand deposits draped the low-lying areas and buried the muddy sediments of the coastal plain [Babu et al., 2007; Srinivasalu et al., 2007]. In addition, erosional features related to the tsunami, such as channels and scarps, have been observed along many parts of the coast (Figure 1a). This tsunami, along with a recorded history of intense monsoons, has highlighted the need for focused research on the role of extreme events in shaping the geological character of India's coastal plains.

  1. A Book Club Sheds Light on Boys and Reading

    ERIC Educational Resources Information Center

    Weih, Timothy G.

    2008-01-01

    This article is about a book club for middle school boys. The idea of a book club for boys came from the author's concern about what he had been hearing and reading about boys falling behind in their reading abilities. The purpose of establishing the club was to discover from the boys themselves what could be done to support them in their reading.…

  2. Shedding Light on the Battlefield: Tactical Applications of Photonic Technology

    DTIC Science & Technology

    2004-11-01

    15 Electronic Alternatives .......................................................................................................16...Electronic Alternatives It is our contention that the significant signal loss and degradation that occur in electrical interconnects as signal speeds...transmission losses and degradation, one can, alternatively , distort data prior to transmission and process it after detection. Further, the bandwidth

  3. Shedding Light on the Inverse-Square Law

    ERIC Educational Resources Information Center

    Uthe, Richard E.

    2004-01-01

    Many students in introductory science courses at both the secondary and tertiary levels learn science as a miscellaneous collection of facts, concepts, and equations that must be memorized to pass examinations. One way to show students that they actually can "do" science is to have them use an observable event to generate a relationship that can…

  4. Shedding light on paraspeckle structure by super-resolution microscopy

    PubMed Central

    Hu, Shi-Bin; Yao, Run-Wen

    2016-01-01

    The nuclear body paraspeckle is built on the lncRNA Neat1 and plays important roles in gene regulation. In this issue, West et al. (2016. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201601071) use super-resolution structured illumination microscopy to show that paraspeckles are organized in a core-shell spheroidal structure composed of Neat1 and seven proteins. PMID:27646270

  5. Shedding Light on the Formation of Gold Nanorods

    NASA Astrophysics Data System (ADS)

    Lopez, Orlando; Hudry, Damien; Nykypanchuk, Dmytro

    A significant interest in the study and synthesis of one-dimensional materials such as nanorods or nanowires is sparked by their potential application in electronics, photonics and biodetection. However, the synthesis of these low dimensional materials is not always reliable due to kinetic effects in symmetry breaking and high sensitivity to impurities. In this work we discuss the synthesis of gold nanorods and new ways to achieve symmetry breaking during the growth from seed solution, hence maximizing the yield of nanorods. We discuss the mechanism involved in symmetry breaking and general strategies to improve the nanorod morphology and synthetic yield. This work can serve as a starting point to design reproducible synthetic strategies for preparing high quality gold nanorods. This project was supported by the U.S. Department of Energy, Office of Science, under the Science Undergraduate Laboratory Internships Program and used resources of the C.F.N., which is a U.S. DOE Facility, at B.N.L., Contract No. DE-SC0012704.

  6. Lidar: shedding new light on habitat characterization and modeling.

    Treesearch

    Kerri T. Vierling; Lee A. Vierling; William A. Gould; Sebastian Martinuzzi; Rick M. Clawges

    2008-01-01

    Ecologists need data on animal–habitat associations in terrestrial and aquatic environments to design and implement effective conservation strategies. Habitat characteristics used in models typically incorporate (1) field data of limited spatial extent and/or (2) remote sensing data that do not characterize the vertical habitat structure. Remote sensing tools that...

  7. Phosphoglucan phosphatase function sheds light on starch degradation.

    PubMed

    Silver, Dylan M; Kötting, Oliver; Moorhead, Greg B G

    2014-07-01

    Phosphoglucan phosphatases are novel enzymes that remove phosphates from complex carbohydrates. In plants, these proteins are vital components in the remobilization of leaf starch at night. Breakdown of starch is initiated through reversible glucan phosphorylation to disrupt the semi-crystalline starch structure at the granule surface. The phosphoglucan phosphatases starch excess 4 (SEX4) and like-SEX4 2 (LSF2) dephosphorylate glucans to provide access for amylases that release maltose and glucose from starch. Another phosphatase, LSF1, is a putative inactive scaffold protein that may act as regulator of starch degradative enzymes at the granule surface. Absence of these phosphatases disrupts starch breakdown, resulting in plants accumulating excess starch. Here, we describe recent advances in understanding the biochemical and structural properties of each of these starch phosphatases.

  8. Laminar Soot Processes Experiment Shedding Light on Flame Radiation

    NASA Technical Reports Server (NTRS)

    Urban, David L.

    1998-01-01

    The Laminar Soot Processes (LSP) experiment investigated soot processes in nonturbulent, round gas jet diffusion flames in still air. The soot processes within these flames are relevant to practical combustion in aircraft propulsion systems, diesel engines, and furnaces. However, for the LSP experiment, the flames were slowed and spread out to allow measurements that are not tractable for practical, Earth-bound flames.

  9. Chlamydial genes shed light on the evolution of photoautotrophic eukaryotes.

    PubMed

    Becker, Burkhard; Hoef-Emden, Kerstin; Melkonian, Michael

    2008-07-15

    Chlamydiae are obligate intracellular bacteria of protists, invertebrates and vertebrates, but have not been found to date in photosynthetic eukaryotes (algae and embryophytes). Genes of putative chlamydial origin, however, are present in significant numbers in sequenced genomes of photosynthetic eukaryotes. It has been suggested that such genes were acquired by an ancient horizontal gene transfer from Chlamydiae to the ancestor of photosynthetic eukaryotes. To further test this hypothesis, an extensive search for proteins of chlamydial origin was performed using several recently sequenced algal genomes and EST databases, and the proteins subjected to phylogenetic analyses. A total of 39 proteins of chlamydial origin were retrieved from the photosynthetic eukaryotes analyzed and their identity verified through phylogenetic analyses. The distribution of the chlamydial proteins among four groups of photosynthetic eukaryotes (Viridiplantae, Rhodoplantae, Glaucoplantae, Bacillariophyta) was complex suggesting multiple acquisitions and losses. Evidence is presented that all except one of the chlamydial genes originated from an ancient endosymbiosis of a chlamydial bacterium into the ancestor of the Plantae before their divergence into Viridiplantae, Rhodoplantae and Glaucoplantae, i.e. more than 1.1 BYA. The chlamydial proteins subsequently spread through secondary plastid endosymbioses to other eukaryotes. Of 20 chlamydial proteins recovered from the genomes of two Bacillariophyta, 10 were of rhodoplant, and 10 of viridiplant origin suggesting that they were acquired by two different secondary endosymbioses. Phylogenetic analyses of concatenated sequences demonstrated that the viridiplant secondary endosymbiosis likely occurred before the divergence of Chlorophyta and Streptophyta. We identified 39 proteins of chlamydial origin in photosynthetic eukaryotes signaling an ancient invasion of the ancestor of the Plantae by a chlamydial bacterium accompanied by horizontal gene transfer. Subsequently, chlamydial proteins spread through secondary endosymbioses to other eukaryotes. We conclude that intracellular chlamydiae likely persisted throughout the early history of the Plantae donating genes to their hosts that replaced their cyanobacterial/plastid homologs thus shaping early algal/plant evolution before they eventually vanished.

  10. Modern vitiligo genetics sheds new light on an ancient disease

    PubMed Central

    SPRITZ, Richard A.

    2013-01-01

    Vitiligo is a complex disorder in which autoimmune destruction of melanocytes results in white patches of skin and overlying hair. Over the past several years, extensive genetic studies have outlined a biological framework of vitiligo pathobiology that underscores its relationship to other autoimmune diseases. This biological framework offers insight into both vitiligo pathogenesis and perhaps avenues towards more effective approaches to treatment and even disease prevention. PMID:23668538

  11. Newly discovered sister lineage sheds light on early ant evolution

    PubMed Central

    Rabeling, Christian; Brown, Jeremy M.; Verhaagh, Manfred

    2008-01-01

    Ants are the world's most conspicuous and important eusocial insects and their diversity, abundance, and extreme behavioral specializations make them a model system for several disciplines within the biological sciences. Here, we report the discovery of a new ant that appears to represent the sister lineage to all extant ants (Hymenoptera: Formicidae). The phylogenetic position of this cryptic predator from the soils of the Amazon rainforest was inferred from several nuclear genes, sequenced from a single leg. Martialis heureka (gen. et sp. nov.) also constitutes the sole representative of a new, morphologically distinct subfamily of ants, the Martialinae (subfam. nov.). Our analyses have reduced the likelihood of long-branch attraction artifacts that have troubled previous phylogenetic studies of early-diverging ants and therefore solidify the emerging view that the most basal extant ant lineages are cryptic, hypogaeic foragers. On the basis of morphological and phylogenetic evidence we suggest that these specialized subterranean predators are the sole surviving representatives of a highly divergent lineage that arose near the dawn of ant diversification and have persisted in ecologically stable environments like tropical soils over great spans of time. PMID:18794530

  12. Skipper genome sheds light on unique phenotypic traits and phylogeny.

    PubMed

    Cong, Qian; Borek, Dominika; Otwinowski, Zbyszek; Grishin, Nick V

    2015-08-27

    Butterflies and moths are emerging as model organisms in genetics and evolutionary studies. The family Hesperiidae (skippers) was traditionally viewed as a sister to other butterflies based on its moth-like morphology and darting flight habits with fast wing beats. However, DNA studies suggest that the family Papilionidae (swallowtails) may be the sister to other butterflies including skippers. The moth-like features and the controversial position of skippers in Lepidoptera phylogeny make them valuable targets for comparative genomics. We obtained the 310 Mb draft genome of the Clouded Skipper (Lerema accius) from a wild-caught specimen using a cost-effective strategy that overcomes the high (1.6 %) heterozygosity problem. Comparative analysis of Lerema accius and the highly heterozygous genome of Papilio glaucus revealed differences in patterns of SNP distribution, but similarities in functions of genes that are enriched in non-synonymous SNPs. Comparison of Lepidoptera genomes revealed possible molecular bases for unique traits of skippers: a duplication of electron transport chain components could result in efficient energy supply for their rapid flight; a diversified family of predicted cellulases might allow them to feed on cellulose-enriched grasses; an expansion of pheromone-binding proteins and enzymes for pheromone synthesis implies a more efficient mate-recognition system, which compensates for the lack of clear visual cues due to the similarities in wing colors and patterns of many species of skippers. Phylogenetic analysis of several Lepidoptera genomes suggested that the position of Hesperiidae remains uncertain as the tree topology varied depending on the evolutionary model. Completion of the first genome from the family Hesperiidae allowed comparative analyses with other Lepidoptera that revealed potential genetic bases for the unique phenotypic traits of skippers. This work lays the foundation for future experimental studies of skippers and provides a rich dataset for comparative genomics and phylogenetic studies of Lepidoptera.

  13. Seronegative celiac disease: Shedding light on an obscure clinical entity.

    PubMed

    Volta, Umberto; Caio, Giacomo; Boschetti, Elisa; Giancola, Fiorella; Rhoden, Kerry J; Ruggeri, Eugenio; Paterini, Paola; De Giorgio, Roberto

    2016-09-01

    Although serological tests are useful for identifying celiac disease, it is well established that a minority of celiacs are seronegative. To define the prevalence and features of seronegative compared to seropositive celiac disease, and to establish whether celiac disease is a common cause of seronegative villous atrophy. Starting from 810 celiac disease diagnoses, seronegative patients were retrospectively characterized for clinical, histological and laboratory findings. Of the 810 patients, fourteen fulfilled the diagnostic criteria for seronegative celiac disease based on antibody negativity, villous atrophy, HLA-DQ2/-DQ8 positivity and clinical/histological improvement after gluten free diet. Compared to seropositive, seronegative celiac disease showed a significantly higher median age at diagnosis and a higher prevalence of classical phenotype (i.e., malabsorption), autoimmune disorders and severe villous atrophy. The most frequent diagnosis in the 31 cases with seronegative flat mucosa was celiac disease (45%), whereas other diagnoses were Giardiasis (20%), common variable immunodeficiency (16%) and autoimmune enteropathy (10%). Although rare seronegative celiac disease can be regarded as the most frequent cause of seronegative villous atrophy being characterized by a high median age at diagnosis; a close association with malabsorption and flat mucosa; and a high prevalence of autoimmune disorders. Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  14. Study Sheds New Light on Postmenopausal Breast Cancer Risk | Poster

    Cancer.gov

    A collaborative study conducted at the Frederick National Lab and published in Cancer Research has provided new insight as to why elevated estrogen levels are associated with an increased risk of breast cancer.

  15. Structural analysis sheds light on APC/C-mediated ubiquitylation.

    PubMed

    Kimata, Yuu; Yamano, Hiroyuki

    2006-01-01

    In the December 22nd issue of Molecular Cell, two groups report refined cryo-electron microscopic structures of the APC/C at approximately 20 A resolution. They also reveal important new features including multiple copies of subunits, dimerization and structural flexibility of the APC/C, which give a hint to solve the mechanisms of the APC/C-dependent ubiquitylation.

  16. The last diadectomorph sheds light on Late Palaeozoic tetrapod biogeography

    PubMed Central

    Liu, Jun; Bever, G. S.

    2015-01-01

    Diadectomorpha is a clade of Late Palaeozoic vertebrates widely recognized as the sister group of crown-group Amniota and the first tetrapod lineage to evolve high-fibre herbivory. Despite their evolutionary importance, diadectomorphs are restricted stratigraphically and geographically, with all records being from the Upper Carboniferous and Lower Permian of North America and Germany. We describe a new diadectomorph, Alveusdectes fenestralis, based on a partial skull from the Upper Permian of China. The new species exhibits the derived mechanism for herbivory and is recovered phylogenetically as a deeply nested diadectid. Approximately 16 Myr younger than any other diadectomorph, Alveusdectes is the product of at least a 46 Myr ghost lineage. How much of this time was probably spent in Russia and/or central Asia will remain unclear until a specimen is described that subdivides this cryptic history, but the lineage assuredly crossed this region before entering the relatively isolated continent of North China. The discovery of Alveusdectes raises important questions regarding diadectomorph extinction dynamics including what, if any, ecological factors limited the diversity of this group in eastern Pangea. It also suggests that increased sampling in Asia will likely significantly affect our views of clade and faunal insularity leading up to the Permo-Triassic extinction. PMID:25948572

  17. Study Sheds Light on Effects of Hate Crimes.

    ERIC Educational Resources Information Center

    Moore, Megan, N.; Harper, Shaun R.; Hildebrand, Emily S.; Burns, Shannon L.

    2000-01-01

    Discussion of effects of hate crime on college campuses reports findings of a survey taken three months after a fatal hate crime. The study found that students in the targeted group, especially females and organizational leaders, had increased extracurricular involvement in campus organizations. Also provides statistics on racist acts on campus…

  18. Cassini sheds light on Titan's second largest lake, Ligeia Mare

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-04-01

    Saturn's largest moon, Titan, is known for its dense, planet-like atmosphere and large lakes most likely made of methane and ethane. It has been suggested that Titan's atmosphere and surface are a model of early Earth. Since the early 2000s, NASA's Cassini space probe has been unlocking secrets of the distant moon.

  19. Study Sheds Light on Effects of Hate Crimes.

    ERIC Educational Resources Information Center

    Moore, Megan, N.; Harper, Shaun R.; Hildebrand, Emily S.; Burns, Shannon L.

    2000-01-01

    Discussion of effects of hate crime on college campuses reports findings of a survey taken three months after a fatal hate crime. The study found that students in the targeted group, especially females and organizational leaders, had increased extracurricular involvement in campus organizations. Also provides statistics on racist acts on campus…

  20. Shedding light on ovothiol biosynthesis in marine metazoans

    PubMed Central

    Castellano, Immacolata; Migliaccio, Oriana; D’Aniello, Salvatore; Merlino, Antonello; Napolitano, Alessandra; Palumbo, Anna

    2016-01-01

    Ovothiol, isolated from marine invertebrate eggs, is considered one of the most powerful antioxidant with potential for drug development. However, its biological functions in marine organisms still represent a matter of debate. In sea urchins, the most accepted view is that ovothiol protects the eggs by the high oxidative burst at fertilization. In this work we address the role of ovothiol during sea urchin development to give new insights on ovothiol biosynthesis in metazoans. The gene involved in ovothiol biosynthesis OvoA was identified in Paracentrotus lividus genome (PlOvoA). PlOvoA embryo expression significantly increased at the pluteus stage and was up-regulated by metals at concentrations mimicking polluted sea-water and by cyclic toxic algal blooms, leading to ovothiol biosynthesis. In silico analyses of the PlOvoA upstream region revealed metal and stress responsive elements. Structural protein models highlighted conserved active site residues likely responsible for ovothiol biosynthesis. Phylogenetic analyses indicated that OvoA evolved in most marine metazoans and was lost in bony vertebrates during the transition from the aquatic to terrestrial environment. These results highlight the crucial role of OvoA in protecting embryos released in seawater from environmental cues, thus allowing the survival under different conditions. PMID:26916575

  1. The last diadectomorph sheds light on Late Palaeozoic tetrapod biogeography.

    PubMed

    Liu, Jun; Bever, G S

    2015-05-01

    Diadectomorpha is a clade of Late Palaeozoic vertebrates widely recognized as the sister group of crown-group Amniota and the first tetrapod lineage to evolve high-fibre herbivory. Despite their evolutionary importance, diadectomorphs are restricted stratigraphically and geographically, with all records being from the Upper Carboniferous and Lower Permian of North America and Germany. We describe a new diadectomorph, Alveusdectes fenestralis, based on a partial skull from the Upper Permian of China. The new species exhibits the derived mechanism for herbivory and is recovered phylogenetically as a deeply nested diadectid. Approximately 16 Myr younger than any other diadectomorph, Alveusdectes is the product of at least a 46 Myr ghost lineage. How much of this time was probably spent in Russia and/or central Asia will remain unclear until a specimen is described that subdivides this cryptic history, but the lineage assuredly crossed this region before entering the relatively isolated continent of North China. The discovery of Alveusdectes raises important questions regarding diadectomorph extinction dynamics including what, if any, ecological factors limited the diversity of this group in eastern Pangea. It also suggests that increased sampling in Asia will likely significantly affect our views of clade and faunal insularity leading up to the Permo-Triassic extinction.

  2. Shedding light on vitamin D and integrative oncology.

    PubMed

    Cantor, Ira

    2008-06-01

    Studies show an important relationship between vitamin D and malignancies, both in prevention and treatment. The extraskeletal actions of vitamin D relevant to oncology include being proapoptotic, antimetastatic, antiangiogenic, antiinflammatory, prodifferentiating, and immunomodulating. Widespread and severe vitamin D deficiencies exist worldwide. Decreased sun exposure, caused by lifestyle changes, as well as fear of skin cancers, is the main cause of these deficiencies. Recommended daily oral intakes, as well as suggested blood levels, are below optimal levels suggested by studies. Improvement in vitamin D status, through lifestyle changes and supplementation, can be of profound benefit regarding the occurrence and mortality of malignancies.

  3. PRISM: Shedding Light on NCTM's Recommendations for the 1980s.

    ERIC Educational Resources Information Center

    Suydam, Marilyn N; Higgins, Jon L.

    1980-01-01

    Information from the Priorities in School Mathematics (PRISM) project, designed as a systematic attempt to assess preferences and priorities for mathematics curriculum change, are presented in relation to eight NCTM recommendations. (MP)

  4. Studies Shed Light on How Cheating Impedes Learning

    ERIC Educational Resources Information Center

    Sparks, Sarah D.

    2011-01-01

    This article reports on new research which shows that, when students succeed at cheating on tests, they get duped into thinking they're smarter than they really are. In four experiments detailed in the March "Proceedings of the National Academy of Sciences", researchers from the Harvard Business School and Duke University found that cheaters pay…

  5. Diamond: shedding light on structure-based drug discovery.

    PubMed

    Brown, David G; Shotton, Elizabeth J

    2015-03-06

    Structure-based drug design has become a key tool for the development of novel drugs. The process involves elucidating the three-dimensional structure of the potential drug molecule bound to the target protein that has been identified as playing a key role in the disease state. Using this three-dimensional information facilitates the process of making improvements to the potential drug molecule by highlighting existing and possible new interactions within the binding site. This knowledge is used to inform increases in potency and selectivity of the molecules as well as to help improve other drug-like properties. The speed and numbers of samples that can be studied, combined with the improved resolution of the structures that can be obtained using synchrotron radiation, have had a significant impact on the utilization of crystallography in the drug discovery process.

  6. Melatonin and human reproduction: shedding light on the darkness hormone.

    PubMed

    Srinivasan, Venkatramanujam; Spence, Warren D; Pandi-Perumal, Seithikurippu R; Zakharia, Rahima; Bhatnagar, Kunwar P; Brzezinski, Amnon

    2009-12-01

    Melatonin, N-acetyl-5-methoxytryptamine, is a molecule with diverse physiological functions. This neuro-hormone affects reproductive performance in a wide variety of species. In most animals, but not exclusively all, melatonin has an antigonadotrophic effect. The seasonal changes in the number of hours per day that melatonin is secreted mediate the temporal coupling of reproductive activity to seasonal changes in day-length. These observations stimulated a search for a role for the pineal gland and melatonin in human reproduction. Clinical experience related to this issue has yielded inconclusive and sometimes conflicting results. This article reviews the current available evidence concerning the effects of melatonin on human reproductive processes (e.g., puberty, ovulation, pregnancy, and fertility). Possible reasons for the vagueness and elusiveness of the clinical effects are discussed.

  7. Shedding light on fish otolith biomineralization using a bioenergetic approach.

    PubMed

    Fablet, Ronan; Pecquerie, Laure; de Pontual, Hélène; Høie, Hans; Millner, Richard; Mosegaard, Henrik; Kooijman, Sebastiaan A L M

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous conclusions in fish ecology and fisheries management. Here we develop and validate a numerical model of otolith biomineralization. Based on a general bioenergetic theory, it disentangles the complex interplay between metabolic and temperature effects on biomineralization. This model resolves controversial issues and explains poorly understood observations of otolith formation. It represents a unique simulation tool to improve otolith interpretation and applications, and, beyond, to address the effects of both climate change and ocean acidification on other biomineralizing organisms such as corals and bivalves.

  8. Absorbent Mind Update: Research Sheds New Light on Montessori Theory.

    ERIC Educational Resources Information Center

    Haines, Annette M.

    1993-01-01

    Explores Maria Montessori's notion that a young child's brain is significantly different from an adult's and that young children develop according to a series of predictable "sensitive periods." Cites numerous empirical studies that support these and other ideas Montessori postulated without the advantage of sophisticated scientific…

  9. 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…

  10. Proteomics shed light on the brassinosteroid signaling mechanisms

    PubMed Central

    Tang, Wenqiang; Deng, Zhiping; Wang, Zhi-Yong

    2009-01-01

    Large numbers of receptor-like kinases (RLKs) play key roles in plant development and defense by perceiving extracellular signals. The mechanisms of ligand-induced kinase activation and downstream signal transduction have been studied for only a few RLK pathways, among which the brassinosteroid (BR) pathway is the best characterized. Recently, proteomics studies identified new components that bridge the last gap in the genetically defined BR-signaling pathway, establishing the first complete pathway from an RLK to transcription factors in plants. Furthermore, analyses of phosphorylation events, mostly by mass spectrometry, provided insights into the mechanistic details of receptor kinase activation and regulation of downstream components by phosphorylation. This review focuses on recent progress in understanding BR signal transduction made by proteomics studies. PMID:20004136

  11. Phylogeographical patterns shed light on evolutionary process in South America.

    PubMed

    Turchetto-Zolet, A C; Pinheiro, F; Salgueiro, F; Palma-Silva, C

    2013-03-01

    The South American continent is composed of several biogeographical regions harbouring the highest biodiversity on the globe, encompassing five of the world's biodiversity 'hot spots'. Nonetheless, the patterns and processes responsible for shaping its astonishing species diversity are largely unknown. Here, we present a review of current South American phylogeographical knowledge based on published articles on this topic. An appraisal of the literature reveals emerging phylogeographical patterns in the biota of South America. The striking phylogeographical divergence observed among organism lineages in South American studies is suggestive of high levels of undocumented species diversity. The interplay between Pleistocene climatic oscillations and Pliocene/Miocene orogenic events has contributed to shaping the current diversity and distribution of modern lineages in both the tropical and temperate regions of South America. Although older divergence times were observed for a range of species, most herpetofauna underwent an intraspecific lineage split much earlier than other organisms. The geographical ranges of species associated with forest habitats were reduced mainly during glacial cycles, whereas species associated with open vegetation domains have shown variable responses to climatic oscillations. The results suggest a highly complex mosaic of phylogeographical patterns in South America. We suggest future research directions to promote a better understanding of the origin and maintenance of the South American biota. © 2012 Blackwell Publishing Ltd.

  12. Studies Shed Light on How Cheating Impedes Learning

    ERIC Educational Resources Information Center

    Sparks, Sarah D.

    2011-01-01

    This article reports on new research which shows that, when students succeed at cheating on tests, they get duped into thinking they're smarter than they really are. In four experiments detailed in the March "Proceedings of the National Academy of Sciences", researchers from the Harvard Business School and Duke University found that cheaters pay…

  13. Shedding light on filovirus infection with high-content imaging.

    PubMed

    Pegoraro, Gianluca; Bavari, Sina; Panchal, Rekha G

    2012-08-01

    Microscopy has been instrumental in the discovery and characterization of microorganisms. Major advances in high-throughput fluorescence microscopy and automated, high-content image analysis tools are paving the way to the systematic and quantitative study of the molecular properties of cellular systems, both at the population and at the single-cell level. High-Content Imaging (HCI) has been used to characterize host-virus interactions in genome-wide reverse genetic screens and to identify novel cellular factors implicated in the binding, entry, replication and egress of several pathogenic viruses. Here we present an overview of the most significant applications of HCI in the context of the cell biology of filovirus infection. HCI assays have been recently implemented to quantitatively study filoviruses in cell culture, employing either infectious viruses in a BSL-4 environment or surrogate genetic systems in a BSL-2 environment. These assays are becoming instrumental for small molecule and siRNA screens aimed at the discovery of both cellular therapeutic targets and of compounds with anti-viral properties. We discuss the current practical constraints limiting the implementation of high-throughput biology in a BSL-4 environment, and propose possible solutions to safely perform high-content, high-throughput filovirus infection assays. Finally, we discuss possible novel applications of HCI in the context of filovirus research with particular emphasis on the identification of possible cellular biomarkers of virus infection.

  14. Shedding light on the black hole mass spectrum.

    NASA Astrophysics Data System (ADS)

    Spera, M.; Giacobbo, N.; Mapelli, M.

    The mass spectrum of stellar black holes (BHs) is highly uncertain. Theoretical models of BH formation strongly depend on the efficiency of stellar winds of the progenitor stars and on the supernova (SN) explosion mechanism. We discuss the BH mass spectrum we obtain using SEVN{}, a new public population-synthesis code that includes up-to-date stellar-wind prescriptions and several SN explosion models. Our models have been used by the LIGO and Virgo collaboration to constrain the properties of the gravitational wave (GW) source GW150914, indicating a sub-solar metallicity environment for its progenitors. We show that our models predict substantially larger BH masses (up to ˜ 100 M⊙) than other population synthesis codes, at low metallicity. In this proceeding, we also discuss the impact of pair-instability SNe on our previously published models.

  15. Shedding Light on the Nature of Seminal Round Cells

    PubMed Central

    Palermo, Gianpiero D.; Neri, Queenie V.; Cozzubbo, Tyler; Cheung, Stephanie; Pereira, Nigel; Rosenwaks, Zev

    2016-01-01

    Introduction In this investigation we assess the incidence of round cells (RCs) in semen samples in our infertile patient population and their significance on intracytoplasmic sperm injection (ICSI) cycle outcomes. We also evaluate the usefulness of RCs as indicators of bacterial infection and highlight the origin of this cell-type, as well as its role in the human ejaculate. Patients and Methods In a prospective fashion, a total of 4,810 ejaculated samples were included in the study during a period of 24 months. RCs were characterized for white blood cell (WBC) components versus exfoliated germ cells by testing for multiple markers of ploidy as well as protamine assays. Cases displaying ≥ 2 x 106/ml RCs were screened for bacteria. Raw specimens containing RC were processed by peroxidase and other leukocyte assays, specific stains for protamines were used to identify spermiogenic stage, aneuploidy (FISH) assessment was carried out, and the presence of various Sertoli-cell cytoplasmic remnants was analyzed to identify and characterize immature germ cells. The effect of RC on clinical outcome was assessed in specimens used for ICSI. Results The average age of the men involved was 39.2 ± 7 years. Semen samples had a mean concentration of 40.7 ± 31 x 106/ml, motility of 42.6 ± 35%, and morphology of 2.3 ± 2%. RCs were identified in 261 specimens, representing a proportion of 5.4%. Men with RCs had comparable age but lower sperm concentration and morphology than the control group (P<0.001). The aneuploidy rate of 4.3% in RCs group was remarkably higher than the control group (2.3%; P<0.001). Sperm aneuploidy rate positively correlated with the number of RCs (P<0.001). Of 44 men, 17 of them in 18 cycles had up to 1.9 x 106/ml RCs without affecting fertilization and clinical pregnancy rates when compared to controls (n = 365 cycles). In 27 men undergoing 33 ICSI cycles with ≥ 2 x 106/ml RCs, the fertilization rate trended lower and the miscarriage rate was significantly increased (P = 0.05). There was lack of correlation between RC and bacteriological growth. Specific markers indicated that seminal RCs are mostly immature germ cells encased in the remnants of Sertoli cell cytoplasm. Moreover, their modest protamine content and their haploid status confirm that they are post-meiotic. Sequential observation in the same man showed that RC episodes were followed by an amelioration of semen parameters, and interestingly, the episodic occurrence of RCs often coincides with flu season peaks. Conclusions Seminal RCs are not a marker of infectiousness but rather a transient indicator of spermatogenic insult that possibly occurs in most men following a mild and transient ailment such as the flu. PMID:26982590

  16. Non-Linear Optical Microscopy Sheds Light on Cardiovascular Disease

    PubMed Central

    Caorsi, Valentina; Toepfer, Christopher; Sikkel, Markus B.; Lyon, Alexander R.; MacLeod, Ken; Ferenczi, Mike A.

    2013-01-01

    Many cardiac diseases have been associated with increased fibrosis and changes in the organization of fibrillar collagen. The degree of fibrosis is routinely analyzed with invasive histological and immunohistochemical methods, giving a limited and qualitative understanding of the tissue's morphological adaptation to disease. Our aim is to quantitatively evaluate the increase in fibrosis by three-dimensional imaging of the collagen network in the myocardium using the non-linear optical microscopy techniques Two-Photon Excitation microscopy (TPE) and Second Harmonic signal Generation (SHG). No sample staining is needed because numerous endogenous fluorophores are excited by a two-photon mechanism and highly non-centrosymmetric structures such as collagen generate strong second harmonic signals. We propose for the first time a 3D quantitative analysis to carefully evaluate the increased fibrosis in tissue from a rat model of heart failure post myocardial infarction. We show how to measure changes in fibrosis from the backward SHG (BSHG) alone, as only backward-propagating SHG is accessible for true in vivo applications. A 5-fold increase in collagen I fibrosis is detected in the remote surviving myocardium measured 20 weeks after infarction. The spatial distribution is also shown to change markedly, providing insight into the morphology of disease progression. PMID:23409139

  17. Shedding light on ovothiol biosynthesis in marine metazoans

    NASA Astrophysics Data System (ADS)

    Castellano, Immacolata; Migliaccio, Oriana; D'Aniello, Salvatore; Merlino, Antonello; Napolitano, Alessandra; Palumbo, Anna

    2016-02-01

    Ovothiol, isolated from marine invertebrate eggs, is considered one of the most powerful antioxidant with potential for drug development. However, its biological functions in marine organisms still represent a matter of debate. In sea urchins, the most accepted view is that ovothiol protects the eggs by the high oxidative burst at fertilization. In this work we address the role of ovothiol during sea urchin development to give new insights on ovothiol biosynthesis in metazoans. The gene involved in ovothiol biosynthesis OvoA was identified in Paracentrotus lividus genome (PlOvoA). PlOvoA embryo expression significantly increased at the pluteus stage and was up-regulated by metals at concentrations mimicking polluted sea-water and by cyclic toxic algal blooms, leading to ovothiol biosynthesis. In silico analyses of the PlOvoA upstream region revealed metal and stress responsive elements. Structural protein models highlighted conserved active site residues likely responsible for ovothiol biosynthesis. Phylogenetic analyses indicated that OvoA evolved in most marine metazoans and was lost in bony vertebrates during the transition from the aquatic to terrestrial environment. These results highlight the crucial role of OvoA in protecting embryos released in seawater from environmental cues, thus allowing the survival under different conditions.

  18. 5. SOUTHERN END OF INTERIOR OF STEEL FRAMEWORK TRAIN SHED ...

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

    5. SOUTHERN END OF INTERIOR OF STEEL FRAMEWORK TRAIN SHED LOOKING SE TO CAVED IN SHED, CENTER, AND BRICK AND STEEL SHED. - Western Railway of Alabama Montgomery Rail Shops, 701 North Perry Street, Montgomery, Montgomery County, AL

  19. 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.

  20. Vortex Shedding Inside a Baffled Air Duct

    NASA Technical Reports Server (NTRS)

    Davis, Philip; Kenny, R. Jeremy

    2010-01-01

    Common in the operation of both segmented and un-segmented large solid rocket motors is the occurrence of vortex shedding within the motor chamber. A portion of the energy within a shed vortex is converted to acoustic energy, potentially driving the longitudinal acoustic modes of the motor in a quasi-discrete fashion. This vortex shedding-acoustic mode excitation event occurs for every Reusable Solid Rocket Motor (RSRM) operation, giving rise to subsequent axial thrust oscillations. In order to better understand this vortex shedding/acoustic mode excitation phenomena, unsteady CFD simulations were run for both a test geometry and the full scale RSRM geometry. This paper covers the results from the subscale geometry runs, which were based on work focusing on the RSRM hydrodynamics. Unsteady CFD simulation parameters, including boundary conditions and post-processing returns, are reviewed. The results were further post-processed to identify active acoustic modes and vortex shedding characteristics. Probable locations for acoustic energy generation, and subsequent acoustic mode excitation, are discussed.

  1. 25. 'HANGAR SHEDS TRUSSES DETAILS; ARCHITECTURAL PLANS ...

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

    25. 'HANGAR SHEDS - TRUSSES - DETAILS; ARCHITECTURAL PLANS - PLANT AREA; MODIFICATION CENTER NO. 1, DAGGETT, CALIFORNIA.' Sections and details of trusses, ironwork, and joints, as modified to show ridge joint detail. As built. This blueline also shows the fire suppression system, added in orange pencil for 'Project 13: Bldgs. T-30, T-50, T-70, T-90' at a later, unspecified date. Contract no. W509 Eng. 2743; File no. 555/84, revision B, dated August 24, 1942. No sheet number. - Barstow-Daggett Airport, Hangar Shed No. 4, 39500 National Trails Highway, Daggett, San Bernardino County, CA

  2. Microfluidic isolation of cancer-cell-derived microvesicles from hetergeneous extracellular shed vesicle populations

    PubMed Central

    Santana, Steven M.; Antonyak, Marc A.; Cerione, Richard A.

    2015-01-01

    Extracellular shed vesicles, including exosomes and microvesicles, are disseminated throughout the body and represent an important conduit of cell communication. Cancer-cell-derived microvesicles have potential as a cancer biomarker as they help shape the tumor microenvironment to promote the growth of the primary tumor and prime the metastatic niche. It is likely that, in cancer cell cultures, the two constituent extracellular shed vesicle subpopulations, observed in dynamic light scattering, represent an exosome population and a cancer-cell-specific microvesicle population and that extracellular shed vesicle size provides information about provenance and cargo. We have designed and implemented a novel microfluidic technology that separates microvesicles, as a function of diameter, from heterogeneous populations of cancer-cell-derived extracellular shed vesicles. We measured cargo carried by the microvesicle subpopulation processed through this microfluidic platform. Such analyses could enable future investigations to more accurately and reliably determine provenance, functional activity, and mechanisms of transformation in cancer. PMID:25342569

  3. Tracking dynamics of photoreceptor disc shedding with adaptive optics-optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Zhang, Furu; Liu, Zhuolin; Kurokawa, Kazuhiro; Miller, Donald T.

    2017-02-01

    Absorption of light by photoreceptors initiates vision, but also leads to accumulation of toxic photo-oxidative compounds in the photoreceptor outer segment (OS). To prevent this buildup, small packets of OS discs are periodically pruned from the distal end of the OS, a process called disc shedding. Unfortunately dysfunction in any part of the shedding event can lead to photoreceptor and RPE dystrophy, and has been implicated in numerous retinal diseases, including age related macular degeneration and retinitis pigmentosa. While much is known about the complex molecular and signaling pathways that underpin shedding, all of these advancements have occurred in animal models using postmortem eyes. How these translate to the living retina and to humans remain major obstacles. To that end, we have recently discovered the optical signature of cone OS disc shedding in the living human retina, measured noninvasively using optical coherence tomography equipped with adaptive optics in conjunction with post processing methods to track and monitor individual cones in 4D. In this study, we improve on this method in several key areas: increasing image acquisition up to MHz A-scan rates, improving reliability to detect disc shedding events, establishing system precision, and developing cone tracking for use across the entire awake cycle. Thousands of cones were successfully imaged and tracked over the 17 hour period in two healthy subjects. Shedding events were detected in 79.5% and 77.4% of the tracked cones. Similar to previous animal studies, shedding prevalence exhibited a diurnal rhythm. But we were surprised to find that for these two subjects shedding occurred across the entire day with broad, elevated frequency in the morning and decreasing frequency as the day progressed. Consistent with this, traces of the average cone OS length revealed shedding dominated in the morning and afternoon and renewal in the evening.

  4. Vortex shedding from solid rocket propellant inhibitors

    NASA Technical Reports Server (NTRS)

    Shu, P. H.; Sforzini, R. H.; Foster, W. A., Jr.

    1986-01-01

    Vortex shedding frequency caused by the protrusion of inhibitors into the flow field of a solid rocket motor is investigated by experimental and mathematical models. The time dependent Navier-Stokes equations are solved using a finite difference technique assuming incompressible, two-dimensional flow under both laminar and turbulent flow conditions. For laminar flow, explicit solutions are obtained using a vorticity-transport equation in place of the Navier-Stokes equations. For turbulent flow, a two-equation (k-epsilon) model is used for turbulent modeling and the SIMPLE algorithm is employed as the computational scheme. Cold flow tests were conducted to confirm the basic flow structure and to determine the vortex shedding frequency under both laminar and turbulent flow conditions. The vortex shedding frequencies were determined using a stroboscope to measure the oscillating frequency of yarn tufts which were fastened to one inhibitor in the models. A hot-film anemometer established the velocity history behind the inhibitor. Good agreement between the theoretical results and measurements of the vortex shedding frequencies is demonstrated.

  5. Vortex shedding from solid rocket propellant inhibitors

    NASA Technical Reports Server (NTRS)

    Shu, P. H.; Sforzini, R. H.; Foster, W. A., Jr.

    1986-01-01

    Vortex shedding frequency caused by the protrusion of inhibitors into the flow field of a solid rocket motor is investigated by experimental and mathematical models. The time dependent Navier-Stokes equations are solved using a finite difference technique assuming incompressible, two-dimensional flow under both laminar and turbulent flow conditions. For laminar flow, explicit solutions are obtained using a vorticity-transport equation in place of the Navier-Stokes equations. For turbulent flow, a two-equation (k-epsilon) model is used for turbulent modeling and the SIMPLE algorithm is employed as the computational scheme. Cold flow tests were conducted to confirm the basic flow structure and to determine the vortex shedding frequency under both laminar and turbulent flow conditions. The vortex shedding frequencies were determined using a stroboscope to measure the oscillating frequency of yarn tufts which were fastened to one inhibitor in the models. A hot-film anemometer established the velocity history behind the inhibitor. Good agreement between the theoretical results and measurements of the vortex shedding frequencies is demonstrated.

  6. Vortex shedding from solid rocket propellant inhibitors

    NASA Astrophysics Data System (ADS)

    Shu, P. H.; Sforzini, R. H.; Foster, W. A., Jr.

    1986-06-01

    Vortex shedding frequency caused by the protrusion of inhibitors into the flow field of a solid rocket motor is investigated by experimental and mathematical models. The time dependent Navier-Stokes equations are solved using a finite difference technique assuming incompressible, two-dimensional flow under both laminar and turbulent flow conditions. For laminar flow, explicit solutions are obtained using a vorticity-transport equation in place of the Navier-Stokes equations. For turbulent flow, a two-equation (k-epsilon) model is used for turbulent modeling and the SIMPLE algorithm is employed as the computational scheme. Cold flow tests were conducted to confirm the basic flow structure and to determine the vortex shedding frequency under both laminar and turbulent flow conditions. The vortex shedding frequencies were determined using a stroboscope to measure the oscillating frequency of yarn tufts which were fastened to one inhibitor in the models. A hot-film anemometer established the velocity history behind the inhibitor. Good agreement between the theoretical results and measurements of the vortex shedding frequencies is demonstrated.

  7. 2. SOUTH FACE OF PYROTECHNIC SHED (BLDG. 757) SHOWING SIGN ...

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

    2. SOUTH FACE OF PYROTECHNIC SHED (BLDG. 757) SHOWING SIGN HOLDER ON LEFT AND ENTRANCE TO TEST CELL. METEOROLOGICAL TOWER AND METEOROLOGICAL SHED (BLDG. 756) IN BACKGROUND ON LEFT; SOUTHEAST CORNER OF GPS AZIMUTH STATION (BLDG. 775) IN BACKGROUND BEHIND AND RIGHT OF PYROTECHNIC SHED. - Vandenberg Air Force Base, Space Launch Complex 3, Pyrotechnic Shed, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  8. Patterns of vortex shedding from an oscillating circular cylinder

    NASA Technical Reports Server (NTRS)

    Chang, Keun-Shik; Sa, Jong-Youb

    1990-01-01

    Vortex shedding from an oscillating circular cylinder was numerically investigated at Re = 100 with the Navier-Stokes equations and the new boundary conditions. The detailed shedding patterns are characterized by means of streakline plotting and lift-coefficient curves. A parameter map is presented which distinguishes the synchronized shedding from the asynchronous and the double vortices shedding from the single vortex shedding. The computational result is in good agreement with earlier experimental results.

  9. Cone outer segment shedding in the goldfish retina characterized with the /sup 3/H-fucose technique

    SciTech Connect

    Balkema, G.W. Jr.; Bunt-Milam, A.H.

    1982-09-01

    After an intravitreal injection of /sup 3/H-fucose, red- and blue-sensitive cone outer segments (OSs) in the goldfish retina became heavily labeled, green-sensitive cone OSs showed light labeling, and rod OSs showed virtually no labeling. Fish were maintained in white light (light/dark: 12 hr/12 hr; 6 to 10 weeks) and were injected with /sup 3/H-fucose 24 hr before sacrifice. After light onset, only phagosomes with no label were found in the retinal pigment epithelium (RPE); after light offset, phagosomes with heavy, light, or no label were found in the RPE. A broad peak of cone OS shedding derived from all cone types was found beginning 2 hr after light offset and returning to baseline levels after 12 hr, with a maximum at 4 to 6 hr. When the white light was replaced with red light during the final 24 hr (irradiance matched to the white light at 625 nm), the green cones showed a reduction in shedding by 62%, the rods showed a 48% reduction in shedding, and the number of heavily labeled phagosomes was reduced by 24% (a value that may reflect normal and red cone shedding and a reduction in blue cone shedding). The results suggest that chromatic stimulation during the light period may influence the shedding response of a given class of cone OS. Finally, the /sup 3/H-fucose technique is useful for determination of the photoreceptor OS from which a given phagosome in the RPE originates in this species.

  10. An Uncharacterized Apocarotenoid-Derived Signal Generated in ζ-Carotene Desaturase Mutants Regulates Leaf Development and the Expression of Chloroplast and Nuclear Genes in Arabidopsis[C][W

    PubMed Central

    Avendaño-Vázquez, Aida-Odette; Cordoba, Elizabeth; Llamas, Ernesto; San Román, Carolina; Nisar, Nazia; De la Torre, Susana; Ramos-Vega, Maricela; Gutiérrez-Nava, María de la Luz; Cazzonelli, Christopher Ian; Pogson, Barry James; León, Patricia

    2014-01-01

    In addition to acting as photoprotective compounds, carotenoids also serve as precursors in the biosynthesis of several phytohormones and proposed regulatory signals. Here, we report a signaling process derived from carotenoids that regulates early chloroplast and leaf development. Biosynthesis of the signal depends on ζ-carotene desaturase activity encoded by the ζ-CAROTENE DESATURASE (ZDS)/CHLOROPLAST BIOGENESIS5 (CLB5) gene in Arabidopsis thaliana. Unlike other carotenoid-deficient plants, zds/clb5 mutant alleles display profound alterations in leaf morphology and cellular differentiation as well as altered expression of many plastid- and nucleus-encoded genes. The leaf developmental phenotypes and gene expression alterations of zds/clb5/spc1/pde181 plants are rescued by inhibitors or mutations of phytoene desaturase, demonstrating that phytofluene and/or ζ-carotene are substrates for an unidentified signaling molecule. Our work further demonstrates that this signal is an apocarotenoid whose synthesis requires the activity of the carotenoid cleavage dioxygenase CCD4. PMID:24907342

  11. Superhydrophobic porous networks for enhanced droplet shedding

    NASA Astrophysics Data System (ADS)

    Liu, Yahua; Wang, Zuankai

    2016-09-01

    Recent research has shown that the use of submillimeter-scale tapered post arrays could generate the so-called pancake bouncing, which is characterized by the fast shedding of impinging drops from the surface in a pancake shape without undergoing the retraction stage as observed on conventional superhydrophobic surfaces. Despite this exciting discovery, the fabrication of this unique superhydrophobic surface with tapered post arrays involves complex processes, hindering its wide applications in practical sectors. Here, we report on the facile strategy to prepare a new hierarchical multilayered superhydrophobic surface directly from commercially available porous matrix that allows for efficient drop shedding. Further study shows that the enhanced drop mobility observed on such a surface is attributed to the synergistic cooperation of hierarchical structures endowing an adequate energy storage and effective energy release. The facile fabrication of superhydrophobic surface with enhanced drop mobility may find many practical applications including anti-icing, dropwise condensation and self-cleaning.

  12. Superhydrophobic porous networks for enhanced droplet shedding.

    PubMed

    Liu, Yahua; Wang, Zuankai

    2016-09-20

    Recent research has shown that the use of submillimeter-scale tapered post arrays could generate the so-called pancake bouncing, which is characterized by the fast shedding of impinging drops from the surface in a pancake shape without undergoing the retraction stage as observed on conventional superhydrophobic surfaces. Despite this exciting discovery, the fabrication of this unique superhydrophobic surface with tapered post arrays involves complex processes, hindering its wide applications in practical sectors. Here, we report on the facile strategy to prepare a new hierarchical multilayered superhydrophobic surface directly from commercially available porous matrix that allows for efficient drop shedding. Further study shows that the enhanced drop mobility observed on such a surface is attributed to the synergistic cooperation of hierarchical structures endowing an adequate energy storage and effective energy release. The facile fabrication of superhydrophobic surface with enhanced drop mobility may find many practical applications including anti-icing, dropwise condensation and self-cleaning.

  13. Superhydrophobic porous networks for enhanced droplet shedding

    PubMed Central

    Liu, Yahua; Wang, Zuankai

    2016-01-01

    Recent research has shown that the use of submillimeter-scale tapered post arrays could generate the so-called pancake bouncing, which is characterized by the fast shedding of impinging drops from the surface in a pancake shape without undergoing the retraction stage as observed on conventional superhydrophobic surfaces. Despite this exciting discovery, the fabrication of this unique superhydrophobic surface with tapered post arrays involves complex processes, hindering its wide applications in practical sectors. Here, we report on the facile strategy to prepare a new hierarchical multilayered superhydrophobic surface directly from commercially available porous matrix that allows for efficient drop shedding. Further study shows that the enhanced drop mobility observed on such a surface is attributed to the synergistic cooperation of hierarchical structures endowing an adequate energy storage and effective energy release. The facile fabrication of superhydrophobic surface with enhanced drop mobility may find many practical applications including anti-icing, dropwise condensation and self-cleaning. PMID:27644452

  14. The phenomenon of dynamic stall. [vortex shedding phenomenon on oscillating airfoils

    NASA Technical Reports Server (NTRS)

    Mccroskey, W. J.

    1981-01-01

    The general features of dynamic stall on oscillating airfoils are explained in terms of the vortex shedding phenomenon, and the important differences between static stall, light dynamic stall, and deep stall are described. An overview of experimentation and prediction techniques is given.

  15. In Silico Methods Shed New Insights Into Cyanide-Caused Cardiac Toxicity

    DTIC Science & Technology

    2005-05-01

    and decreased creatine phosphate production are observed. Mitochondrial myopathies and cytosolic pathologies have been studied, shedding light on...its inhibition of cytochrome oxidase, a mitochondrial enzyme, preventing the transfer of electrons from cytochrome c to molecular oxygen. The...defects, and decreases in enzyme activity affect the cellular energy metabolism.* Calcium balance controls mitochondrial respiration. Mitochondrial

  16. CAD Instructor Designs Eco-Friendly Shed

    ERIC Educational Resources Information Center

    Schwendau, Mark

    2013-01-01

    Dissatisfied with the options offered by big box stores--and wanting to save some money and go as green as possible--the author puts his design and construction skills to good use. In this article, he shares how he designed and built an eco-friendly shed. He says he is very pleased with the results of working with his own design, reducing waste,…

  17. CAD Instructor Designs Eco-Friendly Shed

    ERIC Educational Resources Information Center

    Schwendau, Mark

    2013-01-01

    Dissatisfied with the options offered by big box stores--and wanting to save some money and go as green as possible--the author puts his design and construction skills to good use. In this article, he shares how he designed and built an eco-friendly shed. He says he is very pleased with the results of working with his own design, reducing waste,…

  18. Biology and biogenesis of shed microvesicles.

    PubMed

    Tricarico, Christopher; Clancy, James; D'Souza-Schorey, Crislyn

    2016-08-05

    The ability of cells to transmit bioactive molecules to recipient cells and the extracellular environment is a fundamental requirement for both normal physiology and disease pathogenesis. It has traditionally been thought that soluble factors released from cells were responsible for this cellular signaling but recent research has revealed a fundamental role for microvesicles in this process. Microvesicles are heterogeneous membrane-bound sacs that are shed from the surface of cells into the extracellular environment in a highly regulated process. They are shed following the selective incorporation of a host of molecular cargo including multiple types of proteins and nucleic acids. In addition to providing new insight into the etiology of complex human diseases, microvesicles also show great promise as a tool for advanced diagnosis and therapy as we move forward into a new age of personalized medicine. Here we review current status of the rapidly evolving field of microvesicle biology, highlighting critical regulatory roles for several small GTPases in the biology and biogenesis of shed microvesicles.

  19. Particle shedding and migration from silicone genitourinary prosthetic devices

    SciTech Connect

    Barrett, D.M.; O'Sullivan, D.C.; Malizia, A.A.; Reiman, H.M.; Abell-Aleff, P.C. )

    1991-08-01

    Of 26 patients undergoing revision of genitourinary prostheses the surrounding reactive fibrous capsule was biopsied in 25 and the draining lymph nodes also were biopsied in 4. The prostheses included 16 inflatable and 14 flexible penile devices, and 10 artificial urinary sphincters. Tissue was examined by light and transmission electron microscopy. X-ray microanalysis was done on intracellular and extracellular foreign material from each specimen. Silicone was found in 18 of the 25 periprosthetic specimens and in all 4 lymph nodes. Foreign body granulomas were identified in 14 of these 29 specimens. Examination of new and explanted versions of each prosthesis by scanning electron microscopy revealed free particles of silicone or silicates on the surface of most devices. Pitting and microfissuring were seen on a few of the new devices and on nearly all of the used ones. Thus, genitourinary prostheses shed silicone particles that can be found in the fibrous capsule and draining lymph nodes.

  20. Credit PSR. The flammable waste materials shed appears as seen ...

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

    Credit PSR. The flammable waste materials shed appears as seen when looking south (186°) from South Liquid Loop Road. Note the catch basin for retaining accidentally spilled substances. Wastes are stored in drums and other safety containers until disposal by burning at the Incinerator (4249/E-50) or by other means. Note the nearby sign warning of corrosive, flammable materials, and calling attention to a fire extinguisher; a telephone is provided to call for assistance in the event of an emergency. This structure is isolated to prevent the spread of fire, and it is lightly built so damage from a fire will be inexpensive to repair - Jet Propulsion Laboratory Edwards Facility, Waste Flammable Storage Building, Edwards Air Force Base, Boron, Kern County, CA

  1. Experience from insulators with RTV silicon rubber sheds and shed coatings

    SciTech Connect

    Vlastos, A.E.; Sherif, E. )

    1990-10-01

    Long-rod composite insulators, with weather sheds made of room temperature vulcanizing silicon rubber compounds (RTV), were exposed for many years to HVAC and HVDC under realistic conditions and natural pollution. This paper reports that it was found that the shed material, quite in contrary to the experience gained from insulators with sheds of other organic materials e.g., EPDM rubber, undergoes a slow degradation which improves the already superior water repelling properties of the silicon rubber compounds. The improvement seems to be due to a low molecular layer which is produced on the surface of the insulator sheds. This layer improves the hydrophobicity of the surface, while protecting the surface from further degradation. Weather sheds of porcelain housing coated with a thin layer of RTV give similar results to those obtained with long-rod silicon rubber insulators. The RTV coating, although it led to increased salt deposit density, reduces the leak currents and the withstand of the insulator under the same pollution conditions.

  2. 2. SOUTH FACE OF METEOROLOGICAL SHED (BLDG. 756) WITH METEOROLOGICAL ...

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

    2. SOUTH FACE OF METEOROLOGICAL SHED (BLDG. 756) WITH METEOROLOGICAL DATA ACQUISITION TERMINAL (MDAT) INSIDE BUILDING - Vandenberg Air Force Base, Space Launch Complex 3, Meteorological Shed & Tower, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  3. 1. SOUTHWEST CORNER OF METEOROLOGICAL SHED (BLDG. 756) SOUTH FACE ...

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

    1. SOUTHWEST CORNER OF METEOROLOGICAL SHED (BLDG. 756) SOUTH FACE OF SLC-3W MOBILE SERVICE TOWER IN BACKGROUND. - Vandenberg Air Force Base, Space Launch Complex 3, Meteorological Shed & Tower, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  4. 2. ACID STORAGE SHED, FRONT AND RIGHT SIDES, LOOKING SOUTHWEST. ...

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

    2. ACID STORAGE SHED, FRONT AND RIGHT SIDES, LOOKING SOUTHWEST. - NIKE Missile Base C-84, Acid Storage Shed, North of launch area, northwest of earthen berm of Acid Fueling Station, Barrington, Cook County, IL

  5. VIEW WEST, SOUTH PENN POWERHOUSE, (FROM LEFT) BLEEDER SHED, ENGINE ...

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

    VIEW WEST, SOUTH PENN POWERHOUSE, (FROM LEFT) BLEEDER SHED, ENGINE HOUSE, BELT SHED, ECCENTRIC HOUSE. - South Penn Oil Company, G. M. Mead Lot 492 Lease, Morrison Run Field, Clarendon, Warren County, PA

  6. 9. GENERAL OBLIQUE VIEW OF SOUTH CORNER OF SHED WITH ...

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

    9. GENERAL OBLIQUE VIEW OF SOUTH CORNER OF SHED WITH DERRICK AND RAILWAY PASS-TROUGH ON WHARF, LOOKING NORTH - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  7. 7. GENERAL VIEW OF SOUTHEAST SIDE OF SHED, SHOWING ALL ...

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

    7. GENERAL VIEW OF SOUTHEAST SIDE OF SHED, SHOWING ALL EIGHTEEN LOADING BAYS, LOOKING WEST FROM ACROSS TURNING BASIN - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  8. 10. WIDE GENERAL VIEW OF SHED SHOWING SOUTHWEST FACADE AND ...

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

    10. WIDE GENERAL VIEW OF SHED SHOWING SOUTHWEST FACADE AND TRUCK PLATFORM/STAGING AREA AT SOUTHWEST END OF BUILDING, LOOKING NORTHWEST - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  9. 3. OBLIQUE GENERAL VIEW SHOWING EAST CORNER OF SHED, WITH ...

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

    3. OBLIQUE GENERAL VIEW SHOWING EAST CORNER OF SHED, WITH RAILROAD TRACKS PASSING UNDER DERRICK ALONG WHARF - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  10. 14. GENERAL OBLIQUE VIEW OF WEST CORNER OF SHED, OBSTRUCTED ...

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

    14. GENERAL OBLIQUE VIEW OF WEST CORNER OF SHED, OBSTRUCTED BY LATE METAL BUILDING, LOOKING EAST - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  11. 1. PAINT AND OIL STORAGE SHED, FRONT, LOOKING SOUTHWEST. ...

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

    1. PAINT AND OIL STORAGE SHED, FRONT, LOOKING SOUTHWEST. - NIKE Missile Base SL-40, Paint & Oil Storage Shed, North end of base, northwest of Mess Hall & south of Basketball Court, Hecker, Monroe County, IL

  12. 2. PAINT AND OIL STORAGE SHED, FRONT AND RIGHT SIDES, ...

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

    2. PAINT AND OIL STORAGE SHED, FRONT AND RIGHT SIDES, LOOKING SOUTH. - NIKE Missile Base SL-40, Paint & Oil Storage Shed, North end of base, northwest of Mess Hall & south of Basketball Court, Hecker, Monroe County, IL

  13. East elevation of bunkhouse and agriculture storage sheds, looking west. ...

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

    East elevation of bunkhouse and agriculture storage sheds, looking west. The shower house is adjacent to the storage sheds and just south of the bunkhouse. - Sespe Ranch, Bunkhouse, 2896 Telegraph Road, Fillmore, Ventura County, CA

  14. 9. Relationship of residence, claim house, west tool shed, and ...

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

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

  15. 32. Oakland Port and General Depot. Transit Shed No. 7, ...

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

    32. Oakland Port and General Depot. Transit Shed No. 7, 936 feet, Building 161 TYPICAL SECTION & DETAILS. Sheet 5 of 16 - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  16. 33. Oakland Port and General Depot. Transit Shed No. 7, ...

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

    33. Oakland Port and General Depot. Transit Shed No. 7, 936 feet, Building 127 STAIR & TOILET ROOM DETAILS. Sheet 6 of 16 - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  17. 1. GENERAL VIEW SHOWING NORTHEAST END (FRONT) OF TRANSIT SHED, ...

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

    1. GENERAL VIEW SHOWING NORTHEAST END (FRONT) OF TRANSIT SHED, IN CONTEXT WITH LOADING YARD AND DERRICK, LOOKING WEST - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  18. 35. Oakland Port and General Depot. Transit Shed No. 7, ...

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

    35. Oakland Port and General Depot. Transit Shed No. 7, 936 feet, Building 127 END WALL FRAMING. Sheet 9 of 16 - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  19. 34. Oakland Port and General Depot. Transit Shed No. 7, ...

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

    34. Oakland Port and General Depot. Transit Shed No. 7, 936 feet, Building 127 70'0' TRUSS. Sheet 7 of 16 - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  20. 30. Oakland Port and General Depot. Transit Shed No. 7, ...

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

    30. Oakland Port and General Depot. Transit Shed No. 7, 936 feet, Building 161 PLOT PLAN & TRANSVERSE SECTION. Sheet 1 of 16 - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  1. 31. Oakland Port and General Depot. Transit Shed No. 7, ...

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

    31. Oakland Port and General Depot. Transit Shed No. 7, 936 feet, Building 127 STAIR & TOILET ROOM DETAILS. Sheet 3 of 16 - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  2. View from inside Train Shed looking out through arched opening. ...

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

    View from inside Train Shed looking out through arched opening. - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  3. Detail of arch opening on N elevation of Train Shed. ...

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

    Detail of arch opening on N elevation of Train Shed. - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  4. Cherry picker at end of Train Shed with arm fully ...

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

    Cherry picker at end of Train Shed with arm fully extended and photographer in bucket - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  5. View from inside end of Train Shed showing cherry picker ...

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

    View from inside end of Train Shed showing cherry picker and photographer at work - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  6. Jack Boucher in bucket of cherry picker photographing Train Shed. ...

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

    Jack Boucher in bucket of cherry picker photographing Train Shed. - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  7. Baggage Room as seen from outside end of Train Shed. ...

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

    Baggage Room as seen from outside end of Train Shed. - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  8. Detail of castiron bracket supporting overhang on Train Shed. ...

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

    Detail of cast-iron bracket supporting overhang on Train Shed. - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  9. 28. VIEW, LOOKING SOUTH UNDER EAST SHED AT PLATFORM LEVEL, ...

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

    28. VIEW, LOOKING SOUTH UNDER EAST SHED AT PLATFORM LEVEL, SHOWING RELATIONSHIP OF CONCOURSES TO SHEDS - Pennsylvania Railroad, Harrisburg Station & Trainshed, Market & South Fourth Streets, Harrisburg, Dauphin County, PA

  10. View of EPA Farm storage shed, facing north. Greenhouse is ...

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

    View of EPA Farm storage shed, facing north. Greenhouse is in background - Nevada Test Site, Environmental Protection Agency Farm, Storage Shed, Area 15, Yucca Flat, 10-2 Road near Circle Road, Mercury, Nye County, NV

  11. VIEW NORTHEAST, WEST FRONT OF PACKING SHED (BUILDING 20) AND ...

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

    VIEW NORTHEAST, WEST FRONT OF PACKING SHED (BUILDING 20) AND BAMBOO STAND ALONG SOUTH FRONT - U.S. Plant Introduction Station, Packing Shed, 11601 Old Pond Road, Glenn Dale, Prince George's County, MD

  12. North and east elevations of tractor shed facing southwest ...

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

    North and east elevations of tractor shed facing southwest - Norris Farm, Tractor Shed-Combine Barn, .5 mile west of County Road 857 & .25 mile east of County Road 88/1, Cheat Neck, Monongalia County, WV

  13. South and west elevations of tractor shed facing northeast ...

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

    South and west elevations of tractor shed facing northeast - Norris Farm, Tractor Shed-Combine Barn, .5 mile west of County Road 857 & .25 mile east of County Road 88/1, Cheat Neck, Monongalia County, WV

  14. 3. EAST FACE OF PYROTECHNIC SHED (BLDG. 757); DOORS FOR ...

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

    3. EAST FACE OF PYROTECHNIC SHED (BLDG. 757); DOORS FOR STORAGE ROOMS. SECURITY FENCE ON RIGHT SIDE OF PHOTOGRAPH. - Vandenberg Air Force Base, Space Launch Complex 3, Pyrotechnic Shed, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  15. 2. SHED, SOUTH END OF SHORTER BARRACKS, FRONT AND RIGHT ...

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

    2. SHED, SOUTH END OF SHORTER BARRACKS, FRONT AND RIGHT SIDES, LOOKING SOUTHWEST. - NIKE Missile Base C-84, Paint & Oil Storage Shed, South of Launch Area Entrance Drive, near security fence, Barrington, Cook County, IL

  16. INTERIOR VIEW OF SHED, SHOWING STRUCTURAL SYSTEM AND OVERHEAD DOOR ...

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

    INTERIOR VIEW OF SHED, SHOWING STRUCTURAL SYSTEM AND OVERHEAD DOOR MOUNTING, LOOKING NORTHEAST - Marvine Colliery, Shed, West side Boulevard Avenue, between East Parker Street & Route 380, Scranton, Lackawanna County, PA

  17. 15. Detail view of Sterling Creek lettuce shed showing second ...

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

    15. Detail view of Sterling Creek lettuce shed showing second floor support beams. - Richmond Hill Plantation, Sterling Creek Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  18. 1. View of Sterling Creek lettuce shed looking south, with ...

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

    1. View of Sterling Creek lettuce shed looking south, with road in foreground - Richmond Hill Plantation, Sterling Creek Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  19. 12. Detail view of Sterling Creek lettuce shed showing floor ...

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

    12. Detail view of Sterling Creek lettuce shed showing floor joist and support beams - Richmond Hill Plantation, Sterling Creek Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  20. 5. View of Sterling Creek lettuce shed looking northwest showing ...

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

    5. View of Sterling Creek lettuce shed looking northwest showing office - Richmond Hill Plantation, Sterling Creek Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  1. 13. Detail view of Sterling Creek lettuce shed showing second ...

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

    13. Detail view of Sterling Creek lettuce shed showing second floor window sill - Richmond Hill Plantation, Sterling Creek Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  2. 4. MACHINERY SHED AND STORAGE ROOM ADDITION, SOUTH AND WEST ...

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

    4. MACHINERY SHED AND STORAGE ROOM ADDITION, SOUTH AND WEST WALL LOOKING NORTHEAST SEED STORAGE BUILDING (1963) BEHIND - Tucson Plant Material Center, Machinery Shed, 3241 North Romero Road, Tucson, Pima County, AZ

  3. 2. EXTERIOR OF THE STORAGE SHED LOCATED NEAR THE POOL, ...

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

    2. EXTERIOR OF THE STORAGE SHED LOCATED NEAR THE POOL, BUILDING 305 AND THE TANK, LOOKING NORTHWEST. - Mill Valley Air Force Station, Storage Shed & Tank, East Ridgecrest Boulevard, Mount Tamalpais, Mill Valley, Marin County, CA

  4. 1. EXTERIOR OF THE STORAGE SHED LOCATED NEAR THE POOL, ...

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

    1. EXTERIOR OF THE STORAGE SHED LOCATED NEAR THE POOL, BUILDING 305 AND THE TANK, LOOKING EAST. - Mill Valley Air Force Station, Storage Shed & Tank, East Ridgecrest Boulevard, Mount Tamalpais, Mill Valley, Marin County, CA

  5. 15. Interior view of Cherry Hill lettuce shed showing posts ...

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

    15. Interior view of Cherry Hill lettuce shed showing posts looking towards the chute building - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  6. 9. View of Cherry Hill lettuce shed looking north, with ...

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

    9. View of Cherry Hill lettuce shed looking north, with chute building on the left - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  7. 12. Partial view of Cherry Hill lettuce shed looking northwest ...

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

    12. Partial view of Cherry Hill lettuce shed looking northwest showing office - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  8. 14. Interior view of Cherry Hill lettuce shed looking towards ...

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

    14. Interior view of Cherry Hill lettuce shed looking towards chute building - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  9. 16. Interior view of Cherry Hill lettuce shed looking up ...

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

    16. Interior view of Cherry Hill lettuce shed looking up at the trusses of the second floor - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  10. 3. View of Cherry Hill lettuce shed looking southeast; parking ...

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

    3. View of Cherry Hill lettuce shed looking southeast; parking lot in foreground - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  11. 2. Oblique view of Cherry Hill lettuce shed looking south; ...

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

    2. Oblique view of Cherry Hill lettuce shed looking south; chute building is in background - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  12. 6. Oblique view of Cherry Hill lettuce shed looking northeast, ...

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

    6. Oblique view of Cherry Hill lettuce shed looking northeast, with chute building to the right - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  13. The pineal gland does not control rod outer segment shedding and phagocytosis in the rat retina and pigment epithelium.

    PubMed

    Tamai, M; Teirstein, P; Goldman, A; O'Brien, P; Chader, G

    1978-06-01

    Diurnal patterns of retinal outer segment shedding and phagocytosis by the pigment epithelium were examined in pinealectomized, superior-cervical-ganglionectomized, and sham-operated rats. Phagocytosis was quantitatively similar in all groups. Sharp increases in the number of large phagosomes were observed soon after lights were turned on in the tree sets of animals. Pinealectomized animals kept in constant darkness over a 24 hr period also exhibited normal shedding patterns. Our results suggest that the pineal does not exert a major influence on the daily rhythms of shedding and phagocytosis observed in the retina-pigment epithelium unit.

  14. Shedding of hyaluronate synthase from streptococci.

    PubMed

    Mausolf, A; Jungmann, J; Robenek, H; Prehm, P

    1990-04-01

    Hyaluronate synthase was shed into the culture medium from growing streptococci (group C) together with nascent hyaluronate. The mechanism of solubilization was analysed using isolated protoplast membranes. Solubilization increased when membranes were suspended in larger volumes, but it was temperature-independent and was not inhibited by protease inhibitors. Increased hyaluronate chain length enhanced solubilization. The soluble synthase could re-integrate into Streptococcal membranes in a saturable manner. The soluble synthase behaved like an integral membrane protein, although it was not integrated into phospholipid vesicles. In sucrose velocity centrifugation the synthase had a higher sedimentation rate in detergent-free solution, indicating that it existed in an aggregated state.

  15. Hair shedding score may affect body temperature more than hair coat color during heat stress in weaned beef heifers.

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to evaluate the effect of hair shedding score and hair coat color on the vaginal temperature (VT) of calves during heat stress. Weaned Bos taurus beef heifers (n = 32; BW = 282 ± 6.4 kg) were assigned to a hair coat color class (BLACK; RED; or LIGHT, where LIGHT = yel...

  16. This pineal gland does not mediate phase shifts in the disc shedding rhythm of the rat retina

    SciTech Connect

    Goldman, A.I.

    1982-01-01

    Albino rats were subjected to pinealectomy, superior cervical ganglionectomy, or the appropriate sham preparation and were placed in lighting conditions so that light onset was advanced by 10 hr. After 6 days of this regimen, all animals exhibited a complete shift in their outer segment disc shedding rhythm, indicating that the pineal gland is not a factor in mediating such a shift.

  17. A suggested mode of inheritance for wool shedding in sheep.

    PubMed

    Pollott, G E

    2011-08-01

    The ability of a sheep to shed its own wool has an attraction in scenarios where the costs of harvesting wool outweigh its value. Certain breeds and composites have the ability to shed their wool in the spring, and these are investigated in this work in an attempt to outline the genetics of wool shedding. One flock from a breeding group in Southern England (UK) containing sheep with wool-shedding characteristics provided shedding scores (1 to 5 scale; no shedding to complete shedding) that were used in a range of genetic analyses. The particular nature of wool shedding suggested that there may be a major gene segregating in these populations that facilitates wool shedding. In addition, there was clearly variation among wool shedders in the speed and extent of shedding, so a polygenic trait was also investigated. The breeding group used a range of shedding breeds and composites in a regular program to introduce wool-shedding genes into their flocks. This allowed the testing of Mendelian ratios for shedders:nonshedders in both first-cross and first-backcross animals. Four modes of inheritance were tested: autosomal recessive, sex-linked recessive, autosomal dominant, and sex-linked dominant. The most likely mode of inheritance was autosomal dominant (P < 0.05), with a low level of incomplete penetrance. In first back-cross animals, this mode of inheritance was confirmed but with complete penetrance. Approximately 11% of shedders did not exhibit the trait as lambs. Mixed-model analyses of shedding scores allowed an investigation of factors that affected wool shedding and also the extent of any genetic and permanent animal variance. Shedding score was found to have a heritability of 0.54 ± 0.07 in lambs and 0.26 ± 0.06 in animals of all ages in one flock using Easycare, Wiltshire Horn, Katahdin, and Dorper shedding animals. Shedding score as a lamb had a genetic correlation of 0.94 ± 0.08 with shedding score as a 2 yr old, but at the phenotypic level this

  18. The epithelial barrier is maintained by in vivo tight junction expansion during pathologic intestinal epithelial shedding

    PubMed Central

    Marchiando, Amanda M.; Shen, Le; Graham, W. Vallen; Edelblum, Karen L.; Duckworth, Carrie A.; Guan, Yanfang; Montrose, Marshall H.; Turner, Jerrold R.; Watson, Alastair J.M.

    2011-01-01

    BACKGROUND & AIMS Tumor necrosis factor (TNF) increases intestinal epithelial cell shedding and apoptosis, potentially challenging the barrier between the gastrointestinal lumen and internal tissues. We investigated the mechanism of tight junction remodeling and barrier maintenance, as well as the roles of cytoskeletal regulatory molecules during TNF-induced shedding. METHODS We studied wild-type and transgenic mice that express the fluorescent-tagged proteins enhanced green fluorescent protein–occludin or monomeric red fluorescent protein1–ZO-1. After injection of high doses of TNF (7.5µg, i.p.), laparotomies were performed and segments of small intestine were opened to visualize the mucosa by video confocal microscopy. Pharmacologic inhibitors and knockout mice were used to determine the roles of caspase activation, actomyosin, and microtubule remodeling and membrane trafficking in epithelial shedding. RESULTS Changes detected included redistribution of the tight junction proteins ZO-1 and occluding to lateral membranes of shedding cells. These proteins ultimately formed a funnel around the shedding cell that defined the site of barrier preservation. Claudins, E-cadherin, F-actin, myosin II, Rho-associated kinase (ROCK), and myosin light chain kinase (MLCK) were also recruited to lateral membranes. Caspase activity, myosin motor activity, and microtubules were required to initiate shedding, whereas completion of the process required microfilament remodeling and ROCK, MLCK, and dynamin II activities. CONCLUSIONS Maintenance of the epithelial barrier during TNF-induced cell shedding is a complex process that involves integration of microtubules, microfilaments, and membrane traffic to remove apoptotic cells. This process is accompanied by redistribution of apical junctional complex proteins to form intercellular barriers between lateral membranes and maintain mucosal function. PMID:21237166

  19. Why does Viola hondoensis (Violaceae) shed its winter leaves in spring?

    PubMed

    Hikosaka, Kouki; Kawauchi, Yoshie; Kurosawa, Takahide

    2010-12-01

    Viola hondoensis is a perennial herb that inhabits the understory of temperate, deciduous forests. It is an evergreen plant with a leaf life span that is shorter than a year. Its summer leaves are produced in spring and shed in autumn; winter leaves are produced in autumn and shed in spring. Here we asked why the plant sheds its winter leaves in spring, though climate conditions improve from spring to summer. We proposed four hypotheses for the cause of shedding: (1) changes in seasonal environment such as day length or air temperature, (2) shading by canopy deciduous trees, (3) self-shading by taller summer leaves, and (4) competition for nutrients between summer and winter leaves. • To test these hypotheses, we manipulated the environment of winter leaves: (1) plants were transplanted to the open site where there was no shading by canopy trees. (2) Petioles of summer leaves were anchored to the soil surface to avoid shading of winter leaves. (3) Sink organs were removed to eliminate nutrient competition. • Longevity of winter leaves was extended when shading by summer leaves was eliminated and when sink organs were removed, but not when plants were transplanted to the open site. • We conclude that the relative difference in light availability between summer and winter leaves is a critical factor for regulation of leaf shedding, consistent with the theory of maximization of the whole-plant photosynthesis.

  20. Shed syndecan-2 enhances tumorigenic activities of colon cancer cells

    PubMed Central

    Choi, Sojoong; Choi, Youngsil; Jun, Eunsung; Kim, In-San; Kim, Seong-Eun; Jung, Sung-Ae; Oh, Eok-Soo

    2015-01-01

    Because earlier studies showed the cell surface heparan sulfate proteoglycan, syndecan-2, sheds from colon cancer cells in culture, the functional roles of shed syndecan-2 were assessed. A non-cleavable mutant of syndecan-2 in which the Asn148-Leu149 residues were replaced with Asn148-Ile149, had decreased shedding, less cancer-associated activities of syndecan-2 in vitro, and less syndecan-2-mediated metastasis of mouse melanoma cells in vivo, suggesting the importance of shedding on syndecan-2-mediated pro-tumorigenic functions. Indeed, shed syndecan-2 from cancer-conditioned media and recombinant shed syndecan-2 enhanced cancer-associated activities, and depletion of shed syndecan-2 abolished these effects. Similarly, shed syndecan-2 was detected from sera of patients from advanced carcinoma (625.9 ng/ml) and promoted cancer-associated activities. Furthermore, a series of syndecan-2 deletion mutants showed that the tumorigenic activity of shed syndecan-2 resided in the C-terminus of the extracellular domain and a shed syndecan-2 synthetic peptide (16 residues) was sufficient to establish subcutaneous primary growth of HT29 colon cancer cells, pulmonary metastases (B16F10 cells), and primary intrasplenic tumor growth and liver metastases (4T1 cells). Taken together, these results demonstrate that shed syndecan-2 directly enhances colon cancer progression and may be a promising therapeutic target for controlling colon cancer development. PMID:25686828

  1. Shedding of hyaluronate synthase from streptococci.

    PubMed Central

    Mausolf, A; Jungmann, J; Robenek, H; Prehm, P

    1990-01-01

    Hyaluronate synthase was shed into the culture medium from growing streptococci (group C) together with nascent hyaluronate. The mechanism of solubilization was analysed using isolated protoplast membranes. Solubilization increased when membranes were suspended in larger volumes, but it was temperature-independent and was not inhibited by protease inhibitors. Increased hyaluronate chain length enhanced solubilization. The soluble synthase could re-integrate into Streptococcal membranes in a saturable manner. The soluble synthase behaved like an integral membrane protein, although it was not integrated into phospholipid vesicles. In sucrose velocity centrifugation the synthase had a higher sedimentation rate in detergent-free solution, indicating that it existed in an aggregated state. Images Fig. 2. Fig. 3. Fig. 5. PMID:2109602

  2. Coupling of vortex shedding with a cavity

    NASA Astrophysics Data System (ADS)

    Kawahashi, Masaaki; Brocher, Eric; Collini, Paul

    1988-09-01

    A pulsating flow within a tube with one end sealed and the other end open, facing a low-velocity wind tunnel flow, may be generated by using a wedge trip placed upstream of the open end of the tube. However, a reasonable explanation about the generating mechanism of the pulsating flow within the resonator coupled with a tripping device has not been given yet. In order to get a better understanding of the coupling of the flow around the wedge trip and the flow oscillation within the resonator, the interaction between the wedge wake and the pulsating flow has been experimentally investigated by means of the hydraulic analogy. The results of flow visualization with shadow-graph technique have provided a good understanding of the coupling phenomena of vortex shedding on the wedge with the flow at the resonator mouth.

  3. Fecal shedding of Salmonella in exotic felids.

    PubMed

    Clyde, V L; Ramsay, E C; Bemis, D A

    1997-06-01

    Two collections of exotic felids were screened for the presence of Salmonella by selective fecal culture utilizing selenite broth and Hektoen enteric agar. In > 90% of the samples, Salmonella was isolated from a single culture. A commercial horsemeat-based diet was fed in both collections, and one collection also was fed raw chicken. Salmonella was cultured from the raw chicken and the horsemeat diet for both collections. Multiple Salmonella serotypes were identified, with S. typhimurium and S. typhimurium (copenhagen) isolated most frequently. Approximately half of the Salmonella isolates demonstrated multiple antibiotic resistance. The ability to harbor Salmonella as normal nonpathogenic bacteria of the gastrointestinal tract may be a physiological adaptation to carnivory. The high rate of fecal shedding of Salmonella in healthy individuals clouds the interpretation of a positive fecal culture in an ill felid, or one with diarrhea. All zoo employees having contact with cat feces or raw diets have a high rate of occupational exposure to Salmonella and should exercise appropriate hygienic precautions.

  4. New rain shed (Building No. 241) interior showing posts, braces, ...

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

    New rain shed (Building No. 241) interior showing posts, braces, and roof structure. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  5. ALTERNATE VIEW OF PENSTOCK SHED, NORTH ELEVATION OF POWERHOUSE, TRANSFORMERS, ...

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

    ALTERNATE VIEW OF PENSTOCK SHED, NORTH ELEVATION OF POWERHOUSE, TRANSFORMERS, AND HYDRAULIC PUMPHOUSE, INCLUDING HYDRAULIC OIL TANK - Folsom Powerhouse, Adjacent to American River, Folsom, Sacramento County, CA

  6. 19. ALTERNATE VIEW OF PENSTOCK SHED, NORTH ELEVATION OF POWERHOUSE, ...

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

    19. ALTERNATE VIEW OF PENSTOCK SHED, NORTH ELEVATION OF POWERHOUSE, TRANSFORMERS, AND HYDRAULIC PUMPHOUSE, INCLUDING HYDRAULIC OIL TANK - Folsom Powerhouse, Adjacent to American River, Folsom, Sacramento County, CA

  7. 17. VIEW LOOKING NORTHEAST, SHOWING SORTING AND SHIPPING SHED WITH ...

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

    17. VIEW LOOKING NORTHEAST, SHOWING SORTING AND SHIPPING SHED WITH SAWMILL BEHIND - Ichabod T. Williams & Sons Sawmill & Veneer Plant, Roosevelt Avenue at Carteret Avenue, Carteret, Middlesex County, NJ

  8. SOUTH END OF FURNACE WITH CAST AND ENGINE SHED IN ...

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

    SOUTH END OF FURNACE WITH CAST AND ENGINE SHED IN FOREGROUND, LOOKING NORTH-NORTHEAST. - Tannehill Furnace, 12632 Confederate Parkway, Tannehill Historical State Park, Bucksville, Tuscaloosa County, AL

  9. Vortex shedding lock-in on tapered bodies of various polygonal cross-sections

    NASA Astrophysics Data System (ADS)

    Ocampo, Jaime A.

    This research project was done to investigate the effects of taper on vortex shedding coherence on High Mast Lighting Towers (HMLTs) with models of 8-, 12-, and 16-sided polygonal cross-section. The models are mounted on springs to recreate a flutter phenomenon seen on high mast lighting towers and left to move freely (with an extra "clamped" or stationary configuration) within the wind tunnel in the cross-wind direction. Later, the model was forced to oscillate at specified frequencies and amplitudes and the resulting wake and surface pressures were recorded and compared to the freemoving and clamped cases. The study aims to study the characteristics of a "lock-in" phenomenon, that is, a range of diameters where instead of different shedding frequencies for different diameters, there is a single shedding frequency for different diameters. This goes contrary to the standard for vortex shedding model characterized by the Strouhal relation. Results show the existence of vortex cell shedding for clamped models. Using a motor and a forcing cam to recreate the elastic movement of the HMLT in ambient conditions has yielded a specific range of diameters to determine the size of the locked in vortex cells. According to standard Department of Transportation manufacturing standards for taper, the lock in distance for small excitations (0.1 inches) would be approximately 10 feet in size in the spanwise direction. This study yields information on vortex cells, their change with forcing excitation, the boundaries between the vortex cells, the changes with Reynolds number and cross-sectional shape, and several other parameters.

  10. Hydrogen Bubbles as a Visualization Tool for Cylinder Shedding

    NASA Astrophysics Data System (ADS)

    Sigurdson, Lorenz; Gilbert, Stuart

    2004-11-01

    We examine the behavior of hydrogen bubbles formed by electrolysis of water on a 2.54 mm cylindrical electrode in a water tunnel. The Reynolds Number based on cylinder diameter varies from 400 to 1100, and tunnel velocities range from 17 to 50 cm/s. At the lowest velocity buoyancy is a strong effect which inhibits accurate flow tracking by the bubbles. This effect largely disappears by 25 cm/s. As the tunnel velocity increases, bubble size decreases, reflected light for photography is reduced, and bubbles begin to track the von Karman vortex street vortex cores near the cylinder. The vortex cores have a sufficiently low pressure to capture the bubbles. Vortex street wavelength is seen to discretely increase as vortices proceed downstream. The location of this scale-change becomes nearer the cylinder as Re increases. Voids of bubbles occur in continuous linear downstream segments originating near the cylinder. They seem to be due to vortex modification in the wake similar to what other cylinder shedding researchers have found.

  11. The role of vortex shedding in a bluff-body combustor

    NASA Astrophysics Data System (ADS)

    Roquemore, W. M.; Tankin, R. S.; Chiu, H. H.; Lottes, S. A.

    A bluff body research combustor has been developed for evaluating the performance of conventional probes and advanced laser techniques, and for conducting experiments to aid in the evaluation and development of combustion models. One of the objectives of the present paper is related to the introduction of a two-dimensional (2-D) sheet-lighting technique coupled with a fast chemically reacting system which can provide detailed visualization of turbulent mixing processes without heat release. A second objective of the paper involves the use of the sheet-lighting technique to investigate the role of vortex shedding in the bluff body combustor.

  12. 3. GENERAL VIEW OF 1946 ADDITIONS. WHEN THE FREIGHT SHED ...

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

    3. GENERAL VIEW OF 1946 ADDITIONS. WHEN THE FREIGHT SHED WAS CONVERTED TO PASSENGER USE THESE STRUCTURES WERE BUILT TO MOVE FREIGHT FROM THE SHED TO TRUCKS PARKED AT THESE LOADING DOCKS. - North Central Railroad, Baltimore Freight House, Guilford & Centre Streets, Baltimore, Independent City, MD

  13. 126. EXTERIOR VIEW, LOOKING NORTH, SHOWING CAST SHED NO. 2, ...

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

    126. EXTERIOR VIEW, LOOKING NORTH, SHOWING CAST SHED NO. 2, FURNACE NO. 2, STOVES, POWER HOUSE, STACKS, FURNACE NO. 1 CAST SHED. FURNACE NO. 2 IS IN PROCESS OF RESTORATION. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  14. View to westsouthwest, with shed at left, showing east end ...

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

    View to west-southwest, with shed at left, showing east end and north side. Drew-Sherwood Barn (HABS No. CA-2610-C) at right rear. - Drew-Sherwood Farm, Shed, 7927 Elk Grove Boulevard, Elk Grove, Sacramento County, CA

  15. Detail of old rain shed (Building No. 43) showing vertical ...

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

    Detail of old rain shed (Building No. 43) showing vertical posts. Note rock foundations of wood tanks once located under the rain shed on the ground at center of photograph. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  16. 26. VIEW OF METAL SHED OVER SHIELDING TANK WITH CAMERA ...

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

    26. VIEW OF METAL SHED OVER SHIELDING TANK WITH CAMERA FACING SOUTHWEST. SHOWS OPEN SIDE OF SHED ROOF, HERCULON SHEET, AND HAND-OPERATED CRANE. TAKEN IN 1983. INEL PHOTO NUMBER 83-476-2-9, TAKEN IN 1983. PHOTOGRAPHER NOT NAMED. - Idaho National Engineering Laboratory, Advanced Reentry Vehicle Fusing System, Scoville, Butte County, ID

  17. NORTH ELEVATION. HAZARDOUS MATERIAL STORAGE SHED IS VISIBLE AT THE ...

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

    NORTH ELEVATION. HAZARDOUS MATERIAL STORAGE SHED IS VISIBLE AT THE FAR RIGHT. DOCKSIDE STORAGE SHED IS VISIBLE IN THE DISTANCE. LAKE WORTH INLET AND THE TOWN OF PALM BEACH ARE IN THE BACKGROUND. - U.S. Coast Guard Lake Worth Inlet Station, Boathouse, Peanut Island, Riviera Beach, Palm Beach County, FL

  18. 17. Forge building, fuel storage shed, and foundry, 1906 Photocopied ...

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

    17. Forge building, fuel storage shed, and foundry, 1906 Photocopied from a photograph by Thomas S. Bronson, 'Group at Whitney Factory, 5 November 1906,' NHCHSL. The most reliable view of the fuel storage sheds and foundry, together with a view of the forge building. - Eli Whitney Armory, West of Whitney Avenue, Armory Street Vicinity, Hamden, New Haven County, CT

  19. 1. VIEW OF WEST AND SOUTH FACES OF PYROTECHNIC SHED ...

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

    1. VIEW OF WEST AND SOUTH FACES OF PYROTECHNIC SHED (BLDG. 757). ENTRANCE TO TEST CELL ON SOUTH SIDE; ENTRANCE TO PERSONNEL ROOM ON WEST SIDE. SECURITY FENCE BETWEEN SLC-3E AND SLC-3W IN BACKGROUND. - Vandenberg Air Force Base, Space Launch Complex 3, Pyrotechnic Shed, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  20. 11. FREIGHT YARDS AT KEYSER. TRAIN SHED AND B & ...

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

    11. FREIGHT YARDS AT KEYSER. TRAIN SHED AND B & O STORAGE FACILITY ARE VISIBLE AT LEFT. TURNTABLE LIES OUT OF VIEW BEHIND TRAIN SHED. - Baltimore & Ohio Railroad, Keyser Machine Shop, State Route 46 Northwest of Spring Street, Keyser, Mineral County, WV

  1. Global Vorticity Shedding on Rectangular and Streamlined Foil Geometries

    NASA Astrophysics Data System (ADS)

    Steele, Stephanie; Dahl, Jason; Weymouth, Gabriel; Triantafyllou, Michael

    2012-11-01

    We explore several aspects of the fluid phenomenon we call global vorticity shedding. Global vorticity shedding occurs when an object in a fluid with circulation suddenly vanishes, shedding the entirety of the boundary layer vorticity into the wake at once. Global vorticity shedding is in distinct contrast with traditional massive separation shedding, in which vorticity is shed from a body from only a few separation points into the fluid. In our experiments, we approximate the disappearance of a towed foil by rapidly retracting the foil in the span-wise direction. We show that for a square-tipped vanishing foil at an angle of attack, the globally shed boundary layer vorticity forms into primary vortices, which evolve and eventually amalgamate with secondary vortices to leave two lasting vortices in the wake. The secondary vortices are a result of three-dimensionality in the flow. We further explore streamlined foil geometries to achieve a simpler and less three-dimensional wake. Vortex formation times are small, with vortices fully formed nearly instantaneously in the flow, making the application of global vorticity shedding promising for a force transducer to impart large and fast maneuvering forces on an underwater vehicle. This research was made with Government support under and awarded by DoD, Air Force Office of Scientific Research, National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168a.

  2. 27. GENERAL INTERIOR VIEW SHOWING SOUTH CORNER OF SHED WITH ...

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

    27. GENERAL INTERIOR VIEW SHOWING SOUTH CORNER OF SHED WITH ONE-STORY OFFICES, SHOWING TYPICAL COLUMN BASE WITH TIMBER BOLTED TO STEEL 'L' SHOE - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  3. Acetylsalicylic Acid Treatment Improves Differentiation and Immunomodulation of SHED

    PubMed Central

    Liu, Y.; Chen, C.; Liu, S.; Liu, D.; Xu, X.; Chen, X.

    2015-01-01

    Stem cells from exfoliated deciduous teeth (SHED) possess multipotent differentiation and immunomodulatory properties. They have been used for orofacial bone regeneration and autoimmune disease treatment. In this study, we show that acetylsalicylic acid (ASA) treatment is able to significantly improve SHED-mediated osteogenic differentiation and immunomodulation. Mechanistically, ASA treatment upregulates the telomerase reverse transcriptase (TERT)/Wnt/β-catenin cascade, leading to improvement of SHED-mediated bone regeneration, and also upregulates TERT/FASL signaling, leading to improvement of SHED-mediated T-cell apoptosis and ameliorating disease phenotypes in dextran sodium sulfate–induced colitis mice. These data indicate that ASA treatment is a practical approach to improving SHED-based cell therapy. PMID:25394850

  4. DEM Simulation of Rock Shed Failure due to Rockfall Impact

    NASA Astrophysics Data System (ADS)

    Chen, Jian-An; Lin, Ming-Lang; Wang, Ching-Ping; Lo, Chia-Ming

    2013-04-01

    The rock shed is a more costly but effective traffic facility used to keep out falling rocks in Taiwan. The main function of rock shed is to let the falling rock passing through via the top slab without hitting the road users. The failure mode of the rock shed due to rockfall impact generally includes punching of top slab, flexural cracks of beam, buckling of column, and damage of foundation, etc. Even so, the failure behavior of the rock shed is still complicated and difficult to predict. Accordingly, this study adopts the discrete element program (PFC2D) to simulate the failure behavior of rock shed. A comparison with uniaxial compression test was carried out firstly to determine the micro parameters of structure elements. The model was utilized to simulate the behavior of rock shed with impact load or hitting of falling block separately. Then, a case study of present rock shed of highway NO.18 in middle Taiwan was analyzed. The result indicates that: the primary causes of rock shed failure mode include block size, falling height, impact position, and structure system. The failure mode of punching shear failure or flexural cracks is dominated by block size and falling height. The occurrence of differential settlement is related to impact position and absence of combined footing. Considering the connection of beam and column, the structure is more likely to break at the joints rather than punching of the top slab. As a result, combined footing and beam-to-column joint should be to take into account to obtain safer protection of rock shed. Keywords: rockfall disaster, PFC, rock shed, discrete element method

  5. August 2007 FIFRA Scientific Advisory Panel Recommendations for SHEDS-Dietary and SHEDS-Residential Modules (Summarized) and EPA Responses

    EPA Science Inventory

    Over the past ten years, the Agency has requested the Panel to review several probabilistic dietary exposure software models. These have included DEEM-FCID™, Calendex-FCID, CARES™, LifeLine™, and an earlier (specialized) version of SHEDS (SHEDS-Wood) designed to assess exposure...

  6. August 2007 FIFRA Scientific Advisory Panel Recommendations for SHEDS-Dietary and SHEDS-Residential Modules (Summarized) and EPA Responses

    EPA Science Inventory

    Over the past ten years, the Agency has requested the Panel to review several probabilistic dietary exposure software models. These have included DEEM-FCID™, Calendex-FCID, CARES™, LifeLine™, and an earlier (specialized) version of SHEDS (SHEDS-Wood) designed to assess exposure...

  7. Light in the temples.

    NASA Astrophysics Data System (ADS)

    Krupp, E. C.

    Contents: 1. The dawn of archaeoastronomy. 2. Stalking Lockyer. 3. Solar connotations at Karnak. 4. Solar sanctuaries at Abu Simbel. 5. Another look at the Sun. 6. The great temple of Amun-Re at Karnak. 7. The solar sanctuary of Hatshepsut's mortuary temple at Deir el-Bahri. 8. The Sun temple of Neuserre' at Abu Ghurab. 9. Shedding light on the temples.

  8. 19. RW Meyer Sugar: 18761889. Cooling Shed Interior, 1881. View: ...

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

    19. RW Meyer Sugar: 1876-1889. Cooling Shed Interior, 1881. View: Looking toward west end of cooling shed. After the concentrated syrup flowed out of the sorghum pan it cooled and crystallized in large sugar coolers. The humidity and vapors caused by the sorghum pan would have retarded the crystallizing and cooling of the sugar in the boiling house. In 1881 this shed was constructed to house the coolers and the sugar before it was dried in the centrifugals. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

  9. Numerical Simulations of Vortex Shedding in Hydraulic Turbines

    NASA Technical Reports Server (NTRS)

    Dorney, Daniel; Marcu, Bogdan

    2004-01-01

    Turbomachines for rocket propulsion applications operate with many different working fluids and flow conditions. Oxidizer boost turbines often operate in liquid oxygen, resulting in an incompressible flow field. Vortex shedding from airfoils in this flow environment can have adverse effects on both turbine performance and durability. In this study the effects of vortex shedding in a low-pressure oxidizer turbine are investigated. Benchmark results are also presented for vortex shedding behind a circular cylinder. The predicted results are compared with available experimental data.

  10. Thermal control of rod outer segment length and shedding in a fish, Fundulus zebrinus.

    PubMed

    Allen, D M

    1995-08-01

    The effects of temperature on rod outer segment (ROS) length and membrane shedding were studied in a cyprinodont fish, Fundulus zebrinus. After 30 days in 14L/10D cyclic light and 17 degrees C, ROS length averaged 41.2 microns. Fish were then exposed to 7, 17 or 27 degrees C for 10 and 25 days before being sampled 5 hr before and 1-4 hr after light onset. In 7 degrees C ROS shortened to 83.5% of initial controls within 10 days, then only 4.1% further, to 79.4% by day 25 (34.4, 32.7 microns). ROS length did not change significantly in fish remaining at 17 degrees C (39.7 and 40.7 microns at day 10 and 25) or in fish moved to 27 degrees C (41.7 and 41.6 microns). Phagosomes were most numerous in 7 degrees C and least numerous in 17 degrees C, but varied in overall size among the largest phagosomes being more common after light onset. After light onset at day 25, the estimated volume per phagosome was 1.14, 4.73 and 5.75 microns 3 in 7, 17 and 27 degrees C. Total phagosome volume per 100 microns RPE at 27 degrees C was generally double that at 17 degrees C. Apparently, in F. zebrinus, the number of disks shed from ROS is adjusted during thermal acclimation to stabilize ROS length.

  11. 12. View of disassembled steam engine sitting in open shed ...

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

    12. View of disassembled steam engine sitting in open shed showing base, columns and entablature. - Hacienda Azucarera La Esperanza, Steam Engine & Mill, 2.65 Mi. N of PR Rt. 2 Bridge over Manati River, Manati, Manati Municipio, PR

  12. 16. View of cane mill sitting under open shed showing ...

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

    16. View of cane mill sitting under open shed showing discharge and top rolls. - Hacienda Azucarera La Esperanza, Steam Engine & Mill, 2.65 Mi. N of PR Rt. 2 Bridge over Manati River, Manati, Manati Municipio, PR

  13. View of Irving intake system showing shed and a portion ...

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

    View of Irving intake system showing shed and a portion of the concrete cover (foreground). Looking south-southwest - Childs-Irving Hydroelectric Project, Irving System, Intake System, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  14. View of Irving Intake System showing shed and steel flume. ...

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

    View of Irving Intake System showing shed and steel flume. Looking west-northwest - Childs-Irving Hydroelectric Project, Irving System, Intake System, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  15. 2016 Targeted Air Shed Grant Program - Closed Announcement FY 2016

    EPA Pesticide Factsheets

    Targeted Air Shed Grant Program proposal for FY 2016. The overall goal of the program is to reduce air pollution in the Nation’s areas with the highest levels of ozone and PM2.5 ambient air concentrations.

  16. 58. LOOKING EAST DOROTHY SIX BLAST FURNACE WITH BRICK SHED ...

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

    58. LOOKING EAST DOROTHY SIX BLAST FURNACE WITH BRICK SHED No. 3 IN FOREGROUND ON RIGHT. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  17. 2. WEST SIDE SHOWING SHED ADDITION, BATHROOM AND WOODPOLE TELECOMMUNICATION ...

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

    2. WEST SIDE SHOWING SHED ADDITION, BATHROOM AND WOOD-POLE TELECOMMUNICATION ANTENNA. NEW CONTROL STATION BUILDING IN BACKGROUND. VIEW TO SOUTHEAST. - Bishop Creek Hydroelectric System, Control Station, Hydrographer's Office, Bishop Creek, Bishop, Inyo County, CA

  18. 103. CABLES ENTERING CABLE TRAY SHED AT EAST OF LSB; ...

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

    103. CABLES ENTERING CABLE TRAY SHED AT EAST OF LSB; OXIDIZER APRON AND LAUNCH PAD IN BACKGROUND - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  19. Environmental perspective facing south showing chicken house, tractor shed, and ...

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

    Environmental perspective facing south showing chicken house, tractor shed, and homestead - Norris Farm, .5 mile west of County Road 857 & .25 mile east of County Road 88/1, Cheat Neck, Monongalia County, WV

  20. GENERAL VIEW OF DEHYDRATER (STRUCTURE 12), SHED (STRUCTURE 18), FRUIT ...

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

    GENERAL VIEW OF DEHYDRATER (STRUCTURE 12), SHED (STRUCTURE 18), FRUIT TRAY STORAGE ROOM (STRUCTURE 11), WITH FRUIT DRYING AREA AND TRAM TRACKS IN FOREGROUND, FROM NORTHWEST - Stevens Ranch Complex, State Route 101, Coyote, Santa Clara County, CA

  1. HISTORIC SHED (NOW WAREHOUSE) AT TRANSFORMER YARD ABOVE GLINES POWERHOUSE. ...

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

    HISTORIC SHED (NOW WAREHOUSE) AT TRANSFORMER YARD ABOVE GLINES POWERHOUSE. PHOTO BY JET LOWE, HAER, 1995. - Elwha River Hydroelectric System, Glines Hydroelectric Dam & Plant, Port Angeles, Clallam County, WA

  2. Interior view of old rain shed (Building No. 43) showing ...

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

    Interior view of old rain shed (Building No. 43) showing truss type A in foreground and truss type B behind that. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  3. Rooftop view of old rain shed (Building No. 43), pipeline ...

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

    Rooftop view of old rain shed (Building No. 43), pipeline on trestle, and water tanks. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  4. Detail of new rain shed (Building No. 241). Note pipeline ...

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

    Detail of new rain shed (Building No. 241). Note pipeline connection from collection trough. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  5. Detail of old rain shed (Building No. 43) with gutter ...

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

    Detail of old rain shed (Building No. 43) with gutter box on northwest side. Maintenance staff in foreground. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  6. Redwood tanks in foreground with old rain shed (Building No. ...

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

    Redwood tanks in foreground with old rain shed (Building No. 43) and steel tanks in background. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  7. Rooftop view of new rain shed (Building No. 241) showing ...

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

    Rooftop view of new rain shed (Building No. 241) showing collection gutter and overhead pipeline. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  8. Interior view of old rain shed (Building No. 43) showing ...

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

    Interior view of old rain shed (Building No. 43) showing redwood dry storage building located inside. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  9. Rooftop detail of new rain shed (Building No. 241) with ...

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

    Rooftop detail of new rain shed (Building No. 241) with flume and overhead pipeline. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  10. Detail of old rain shed (Building No. 43) with collection ...

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

    Detail of old rain shed (Building No. 43) with collection downspouts from gutter to reservoir. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  11. New rain shed (Building No. 241) on right with Tanks ...

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

    New rain shed (Building No. 241) on right with Tanks T5, T4 and T2 on left from front to back. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  12. Detail of old rain shed (Building No. 43) showing vertical ...

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

    Detail of old rain shed (Building No. 43) showing vertical posts on concrete footing with diagonal timber bracing and wire bracing. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  13. New rain shed (Building No. 241), overhead pipeline and raw ...

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

    New rain shed (Building No. 241), overhead pipeline and raw water tank T4. Distribution pump house can be seen at the center of building. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  14. PERSPECTIVE VIEW LOOKING NORTHWEST AT CYANAMIDE (LN) COOLING SHED, MILL ...

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

    PERSPECTIVE VIEW LOOKING NORTHWEST AT CYANAMIDE (L-N) COOLING SHED, MILL BUILDING AND CONVEYOR BRIDGE. NOTE CORNERSTONE ON THE MILL BUILDING. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  15. 3. Peeler Shed, SE side, with blower assembly. This structure ...

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

    3. Peeler Shed, SE side, with blower assembly. This structure was need to move back to the Chipper Building for processing. - Pacific Creosoting Plant, Log Peeling Operation, 5350 Creosote Place, Northeast, Bremerton, Kitsap County, WA

  16. 64. INTERIOR VIEW OF THE CARBIDE COOLING SHED. VIEW IS ...

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

    64. INTERIOR VIEW OF THE CARBIDE COOLING SHED. VIEW IS SHOWING CALCIUM CARBIDE IN COOLING CARS ON THE FLOOR. DECEMBER 26, 1918. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  17. Side elevation of Building 477 showing the shed roof addition ...

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

    Side elevation of Building 477 showing the shed roof addition and horizontal siding at the ends, view facing northwest - U.S. Marine Corps Base Hawaii, Kaneohe Bay, Golf Course Equipment & Repair Shop, Reeves & Moffett Roads, Kaneohe, Honolulu County, HI

  18. PERSPECTIVE VIEW OF OFFICE AND SHED LOOKING EAST (NORTH SIDE ...

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

    PERSPECTIVE VIEW OF OFFICE AND SHED LOOKING EAST (NORTH SIDE OF HOUSE VISIBLE BEHIND OFFICE TO LEFT) - Greenwood Furnace, Bookkeeper's House, East of McAlevy's Fort on State Route 305, McAlevys Fort, Huntingdon County, PA

  19. 7. Detail, machinery shed atop east portal of Tunnel 28, ...

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

    7. Detail, machinery shed atop east portal of Tunnel 28, showing shaft and pulley system, 210mm lens with electronic flash fill. - Central Pacific Transcontinental Railroad, Tunnel No. 28, Milepost 134.75, Applegate, Placer County, CA

  20. View of southernmost section of east facade with Shed in ...

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

    View of southernmost section of east facade with Shed in foreground. View toward north - Naval Air Station Moffett Field, Hanger No. 1, Cummins Avenue, Moffett Field, Sunnyvale, Santa Clara County, CA

  1. 2. WEST ELEVATION, SHOWING TAILRACE AND SLIDING DOOR UNDER SHED ...

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

    2. WEST ELEVATION, SHOWING TAILRACE AND SLIDING DOOR UNDER SHED ROOF. ADMINISTRATIVE OFFICE IS IN BACKGROUND AT RIGHT. VIEW TO EAST-NORTHEAST. - Santa Ana River Hydroelectric System, SAR-3 Powerhouse, San Bernardino National Forest, Redlands, San Bernardino County, CA

  2. 8. Elevator no. 2: Track shed, showing cable and pulleys ...

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

    8. Elevator no. 2: Track shed, showing cable and pulleys for moving train cars, facing east - Washburn Crosby Company Elevators No. 2 & 3, 900 & 1000 Second Avenue, South, Minneapolis, Hennepin County, MN

  3. 30. VIEW OF SOUTH END OF EAST SHED, PLAZA LEVEL, ...

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

    30. VIEW OF SOUTH END OF EAST SHED, PLAZA LEVEL, SHOWING BAGGAGE BRIDGE AND ITS RELATIONSHIP TO THE ELEVATORS AND PLATFORM - Pennsylvania Railroad, Harrisburg Station & Trainshed, Market & South Fourth Streets, Harrisburg, Dauphin County, PA

  4. 2. Relationship of claim house, residence, east tool shed, and ...

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

    2. Relationship of claim house, residence, east tool shed, and garage to overall farmstead site, looking north - George Spangerberger Farmstead, 2012 West Illinois Avenue, South Hutchinson, Reno County, KS

  5. 6. RElationship of residence, claim house, east tool shed, barn, ...

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

    6. RElationship of residence, claim house, east tool shed, barn, garage, and pole building to overall farmstead site, looking northwest - George Spangerberger Farmstead, 2012 West Illinois Avenue, South Hutchinson, Reno County, KS

  6. 11. INTERIOR VIEW OF 19061910 ONESTORY SHED ADDITION, FIRST FLOOR, ...

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

    11. INTERIOR VIEW OF 1906-1910 ONE-STORY SHED ADDITION, FIRST FLOOR, SHOWING ROOF MONITOR, LOOKING NORTHWEST - Massachusetts Mills, Cloth Room-Section 15, 95 Bridge Street, Lowell, Middlesex County, MA

  7. DETAIL OF ELECTRICAL CART, WEST SHED AREA Cape Canaveral ...

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

    DETAIL OF ELECTRICAL CART, WEST SHED AREA - Cape Canaveral Air Force Station, Launch Complex 34, Operations Support Building, Freedom Road, Southwest of Launch Stand CX-34, Cape Canaveral, Brevard County, FL

  8. Insulation Characteristics of Bushing Shed at Cryogenic Temperature

    NASA Astrophysics Data System (ADS)

    Kim, W. J.; Kim, Y. J.; Kim, S. H.

    2014-05-01

    In the development of high-Tc superconducting(HTS) devices, the bushing for HTS devices (HTS bushing) is the core technology, the need to because of supply high voltage to the cable or the winding of the transformer. The lower part of the bushing is exposed to the liquid nitrogen (LN2), and it has many sheds. In particular, the insulation body with sheds and electrical insulation at cryogenic temperature have attracted a great deal of interest from the view point of the size, weight and efficiency of bushing. This study has mainly investigated the shed and insulation body by comparing glass fiber reinforced plastics (GFRP) in LN2. We investigated the surface discharge characteristics according to insulating materials, width and height of the shed.

  9. 1. EXTERIOR VIEW OF THE EXPLOSIVE STORAGE SHED, BUILDING 306, ...

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

    1. EXTERIOR VIEW OF THE EXPLOSIVE STORAGE SHED, BUILDING 306, LOOKING NORTHWEST. - Mill Valley Air Force Station, Explosive Storage, East Ridgecrest Boulevard, Mount Tamalpais, Mill Valley, Marin County, CA

  10. View north, west (back) wall of canal, mu shed in ...

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

    View north, west (back) wall of canal, mu shed in background. - Delaware, Lackawanna & Western Railroad Freight & Rail Yard, Long Slip Canal, New Jersey Transit Hoboken Rail Yard, Hoboken, Hudson County, NJ

  11. 6. VIEW TO WEST, SAMPLING BUILDING, MECHANIC SHED, MILL WAREHOUSE, ...

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

    6. VIEW TO WEST, SAMPLING BUILDING, MECHANIC SHED, MILL WAREHOUSE, DRYERS, AND GRINDING/ROD MILL. - Vanadium Corporation of America (VCA) Naturita Mill, 3 miles Northwest of Naturita, between Highway 141 & San Miguel River, Naturita, Montrose County, CO

  12. 43. PROCESS WELDING SHEDS (FABRICATION SHOPS) ON RIGHT, AND TANK ...

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

    43. PROCESS WELDING SHEDS (FABRICATION SHOPS) ON RIGHT, AND TANK BARGE, CRANES, PAINT SHOP AND PIPE/MACHINE SHOP IN BACKGROUND, LOOKING NORTHEAST - Hillman Barge & Construction Company, Paul Thomas Boulevard, Brownsville, Fayette County, PA

  13. 1. EAST ELEVATION, SHOWING PENTHOUSE, STAIRS, AND SHED USED TO ...

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

    1. EAST ELEVATION, SHOWING PENTHOUSE, STAIRS, AND SHED USED TO TREAT HELICOPTER COMPONENTS. SOUTHEAST DOOR TO BUILDING 10 AT RIGHT. - Hughes Aircraft Company, Garage & Maintenance Building, 6775 Centinela Avenue, Los Angeles, Los Angeles County, CA

  14. 5. DETAIL, STEEL SHED, SOUTHEAST FRONT AND SOUTHWEST SIDE ...

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

    5. DETAIL, STEEL SHED, SOUTHEAST FRONT AND SOUTHWEST SIDE - Mispillion Lighthouse, Beacon Tower, South bank of Mispillion River at it confluence with Delaware River at northeast end of County Road 203, 7 miles east of Milford, Milford, Sussex County, DE

  15. FACING NORTH ALONG TERRACE AVENUE OF MAINTENANCE SHED AND LANDSCAPING ...

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

    FACING NORTH ALONG TERRACE AVENUE OF MAINTENANCE SHED AND LANDSCAPING IN NORTHEASTERN CORNER OF PARK - Candler Park Historic District, Roughly bounded by Moreland, Dekalb, McLendon & Harold Avenues, Matthews Street & Clifton Terrace, Atlanta, Fulton County, GA

  16. VIEW OF NORTHEAST TOWARD MAINTENANCE SHED AT NORTHEAST CORNER OF ...

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

    VIEW OF NORTHEAST TOWARD MAINTENANCE SHED AT NORTHEAST CORNER OF PARK - Candler Park Historic District, Roughly bounded by Moreland, Dekalb, McLendon & Harold Avenues, Matthews Street & Clifton Terrace, Atlanta, Fulton County, GA

  17. 15. Elevator no. 2: Scale floor above track shed, showing ...

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

    15. Elevator no. 2: Scale floor above track shed, showing interlocking levers and beams, facing southeast - Washburn Crosby Company Elevators No. 2 & 3, 900 & 1000 Second Avenue, South, Minneapolis, Hennepin County, MN

  18. Low flow vortex shedding flowmeter for hypergolics/all media

    NASA Technical Reports Server (NTRS)

    Thinh, Ngo

    1990-01-01

    A family of vortex shedding flowmeters for flow measurement of hypergols that requires a long term operation without removal from system lines was further developed. A family of vortex shedding flowmeters without moving parts was designed. The test loop to evaluate the meters for the Freon flow, which simulates the hypergolic fluids, was modified and reconstructed. Preliminary results were obtained on the output frequency characteristics of an 1/2 inch flowmeter as a function of the flow rate.

  19. 4. View north of Lake Whitney Dam. Wood shed at ...

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

    4. View north of Lake Whitney Dam. Wood shed at center of photograph houses a turbine installed in 1932. Brick structure to the left of the turbine shed is a gate house which houses the main valves controlling flow of lake to water to the filter plant. - Lake Whitney Water Filtration Plant, Lake Whitney Dam, East side of Whitney Avenue near intersection with Armory Street, Hamden, New Haven County, CT

  20. 8. MACHINERY SHED STORAGE ROOM ADDITION DETAIL SHOWING MATRIX OF ...

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

    8. MACHINERY SHED STORAGE ROOM ADDITION DETAIL SHOWING MATRIX OF NAILS USED TO ADHERE PORTLAND CEMENT PLASTER, SOUTH ADOBE WALL ADJACENT TO WINDOW Note: Photographs Nos. AZ-159-A-9 through AZ-159-A-10 are photocopies of photographs. The original prints and negatives are located in the SCS Tucson Plant Materials Center, Tucson, Arizona. Photographer Ted F. Spaller. - Tucson Plant Material Center, Machinery Shed, 3241 North Romero Road, Tucson, Pima County, AZ

  1. Vortex shedding effects in grid-generated turbulence

    NASA Astrophysics Data System (ADS)

    Melina, G.; Bruce, P. J. K.; Vassilicos, J. C.

    2016-08-01

    The flow on the centerline of grid-generated turbulence is characterized via hot-wire anemometry for three grids with different geometry: a regular grid (RG60), a fractal grid (FSG17), and a single-square grid (SSG). Due to a higher value of the thickness t0 of its bars, SSG produces greater values of turbulence intensity Tu than FSG17, despite SSG having a smaller blockage ratio. However, the higher Tu for SSG is mainly due to a more pronounced vortex shedding contribution. The effects of vortex shedding suppression along the streamwise direction x are studied by testing a three-dimensional configuration, formed by SSG and a set of four splitter plates detached from the grid (SSG+SP). When vortex shedding is damped, the centerline location of the peak of turbulence intensity xpeak moves downstream and Tu considerably decreases in the production region. For FSG17 the vortex shedding is less intense and it disappears more quickly, in terms of x /xpeak , when compared to all the other configurations. When vortex shedding is attenuated, the integral length scale Lu grows more slowly in the streamwise direction, this being verified both for FSG17 and for SSG+SP. In the production region, there is a correlation between the vortex shedding energy and the skewness and the flatness of the velocity fluctuations. When vortex shedding is not significant, the skewness is highly negative and the flatness is much larger than 3. On the opposite side, when vortex shedding is prominent, the non-Gaussian behavior of the velocity fluctuations becomes masked.

  2. Capacity building in indigenous men's groups and sheds across Australia.

    PubMed

    Southcombe, Amie; Cavanagh, Jillian; Bartram, Timothy

    2015-09-01

    This article presents an investigation into capacity building, at the community level, in Aboriginal and Torres Strait Islander Men's Groups and Sheds. As safe men's spaces, Men's Groups and Sheds represent an ever-growing social, and health and well-being community service across Australia. The study is qualitative and employs 'yarning circles' (focus groups), semi-structured interviews and observations to gather data from 15 Groups/Sheds involving 45 men from urban, regional and remote communities. We found that capacity building is primarily about securing relationships between Group Leaders/Shed Co-ordinators and Government services. Capacity building establishes links to services such as Centrelink, Medicare, Department of Housing, Probation and Control, and positive outcomes such as Indigenous men securing housing and Centrelink payments. Capacity building results in better health outcomes and, educates and empowers men to improve their social, cultural, emotional and economic well-being. It helps men to better connect with family and community. The current research paves the way for countries worldwide to explore the conceptual and empirical approach of capacity building applicable to other Indigenous [and non-Indigenous] Men's Groups/Sheds. We recommend feasibilities studies, on approaches to capacity building in Indigenous Groups/Sheds, be carried out within urban, regional and remote regions across the country. © The Author (2014). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Particles shed from syringe filters and their effects on agitation-induced protein aggregation.

    PubMed

    Liu, Lu; Randolph, Theodore W; Carpenter, John F

    2012-08-01

    We tested the hypothesis that foreign particles shed from filters can accelerate the rate of protein aggregation and particle formation during agitation stress. Various types and brands of syringe filters were tested. Particle counts and size distribution (≥1 µm) in buffer alone or in solutions of keratinocyte growth factor 2 (KGF-2) were determined with a micro-flow imaging. Submicron particle populations were characterized by dynamic light scattering. Loss of soluble protein during filtration or postfiltration incubation was determined by ultraviolet spectroscopy and bicinchoninic acid protein assay. There was a wide range (from essentially none to >100,000/mL) in the counts for at least 1 µm particles shed into buffer or KGF-2 solution from the different syringe filters (with or without borosilicate glass microfibers). Filtration of KGF-2 with units containing glass microfibers above the membrane resulted in 20%-80% loss of protein due to adsorption to filter components. Filtration with systems containing a membrane alone resulted in 0%-20% loss of KGF-2. Effects of 24-h postfiltration incubation were tested on KGF-2 solution filtered with polyether sulfone membrane filters. Loss of soluble protein and formation of particles during agitation were much greater than that in control, unfiltered KGF-2 solutions. Similar acceleration of protein aggregation and particle formation was observed when unfiltered KGF-2 solution was mixed with filtered buffer and agitated. Particle shedding from syringe filters--and the resulting acceleration of protein aggregation during agitation--varied greatly among the different syringe filters and individual units of a given filter type. Our results demonstrate that nanoparticles and microparticles shed from the filters can accelerate protein aggregation and particle formation, especially during agitation. Copyright © 2012 Wiley Periodicals, Inc.

  4. A Novel Load Shedding Scheme for Voltage Stability

    NASA Astrophysics Data System (ADS)

    Damodhar, Sunil S.; Krishna, S.

    2016-12-01

    Undervoltage load shedding serves to maintain voltage stability when a majority of loads are fast acting. An undervoltage load shedding scheme should address two tasks: the detection of voltage instability following a large disturbance and the determination of the amount of load to be shed. Additionally, in case of short-term voltage instability, the scheme should be fast. This paper proposes a method to predict voltage instability arising due to a large disturbance. The amount of load to be shed to maintain voltage stability is then determined from the Thevenin equivalent of the network as seen from the local bus. The proposed method uses local measurements of bus voltage and power, and does not require knowledge of the network. The method is validated by simulation of three test systems subjected to a large disturbance. The proposed scheme is fairly accurate in estimating the minimum amount of load to be shed to maintain stability. The method is also successful in maintaining stability in cases where voltage collapse is detected at multiple buses.

  5. Exploitation of syndecan-1 shedding by Pseudomonas aeruginosa enhances virulence.

    PubMed

    Park, P W; Pier, G B; Hinkes, M T; Bernfield, M

    2001-05-03

    Cell-surface heparan sulphate proteoglycans (HSPGs) are ubiquitous and abundant receptors/co-receptors of extracellular ligands, including many microbes. Their role in microbial infections is poorly defined, however, because no cell-surface HSPG has been clearly connected to the pathogenesis of a particular microbe. We have previously shown that Pseudomonas aeruginosa, through its virulence factor LasA, enhances the in vitro shedding of syndecan-1-the predominant cell-surface HSPG of epithelia. Here we show that shedding of syndecan-1 is also activated by P. aeruginosa in vivo, and that the resulting syndecan-1 ectodomains enhance bacterial virulence in newborn mice. Newborn mice deficient in syndecan-1 resist P. aeruginosa lung infection but become susceptible when given purified syndecan-1 ectodomains or heparin, but not when given ectodomain core protein, indicating that the ectodomain's heparan sulphate chains are the effectors. In wild-type newborn mice, inhibition of syndecan-1 shedding or inactivation of the shed ectodomain's heparan sulphate chains prevents lung infection. Our findings uncover a pathogenetic mechanism in which a host response to tissue injury-syndecan-1 shedding-is exploited to enhance microbial virulence apparently by modulating host defences.

  6. Vortex shedding induced dynamic response of marine risers

    SciTech Connect

    Rajabi, F.; Mangiavacchi, A.; Zedan, M.F.

    1984-06-01

    An analytical model to predict the dynamic response of a riser in regular waves or in current to vortex shedding-induced lift forces is described. The riser is treated as a continuous beam under tension. A modal superposition scheme is used to solve the linearized equation of motion in the frequency domain. The excitation lift force is represented by a harmonic function with a frequency equal to the dominant vortex shedding frequency. Empirical correlations are used to determine the lift coefficients and shedding frequencies along the riser. Lift amplification is considered at or near the ''lock-in'' conditions. The fluid resistance to riser oscillations is represented by a Morison's equation-type expression.

  7. Circulation shedding in viscous starting flow past a flat plate

    NASA Astrophysics Data System (ADS)

    Nitsche, Monika; Xu, Ling

    2013-11-01

    Numerical simulations of viscous flow past a flat plate moving in direction normal to itself reveal details of the vortical structure of the flow. At early times, most of the vorticity is attached to the plate. We introduce a definition of the shed circulation at all times and show that it indeed represents vorticity that separates and remains separated from the plate. Scaling laws for the shed circulation, and contributions to the shedding rate across various boundary components are presented, as well as their dependence on Reynolds number. The simulations provide benchmark results to evaluate simpler separation models such as point vortex and vortex sheet models. A comparison with vortex sheet results is included.

  8. Numerical and Experimental Study on Unsteady Shedding of Partial Cavitation

    NASA Astrophysics Data System (ADS)

    Ji, Bin; Luo, Xianwu; Wu, Yulin; Peng, Xiaoxing; Xu, Hongyuan

    Periodically unsteady shedding of partial cavity and forming of cavitation cloud have a great influence on hydraulic performances and cavitation erosion for ship propellers and hydro machines. In the present study, the unsteady cavitating flow around a hydrofoil has been calculated by using the single fluid approach with a developed cavitation mass transfer expression based on the vaporization and condensation of the fluid. The numerical simulation depicted the unsteady shedding of partial cavity, such as the process of cavity developing, breaking off and collapsing in the downstream under the steady incoming flow condition. It is noted that good agreement between the numerical results and that of experiment conducted at a cavitation tunnel is achieved. The cavitating flow field indicates that the cavity shedding was mainly caused by the re-entrant jet near cavity trailing edge, which was also clearly recorded by high-speed photographing.

  9. When the light shed by God is dimmer than the light shed upon God: countertransference illumination of latent religious object representations of a Jewish patient in psychoanalysis.

    PubMed

    Spero, Moshe Halevi

    2009-01-01

    A report is offered of the psychoanalysis of an emotionally constricted, religiously devout ko'hen, a member of the Jewish priestly class, undertaken with the author, himself a religiously committed Jew. While the analysand brought a great deal of material to his hours and was deeply committed to the analysis, the sessions were emotionally vapid, obsessively repetitious and ruminative. For more than three years, the patient's steadfast production of a plethora of dreams did not much alter the brittle quality of work and the restricted range of the transference. At first, though religious themes as such abounded, the patient's relationship with God and his representation of God seemed to play no role in the working dynamic. This vacancy played a negating or absenting role, distancing the analyst from his own sense of a living divinity, parallel to the basic aporia in the patient's emotional representation of his significant parental objects and the image of God that rested upon the former. The countertransference dimension of the analytic relationship peaked during a spontaneous but complex enactment that helped refract the patient's and analyst's shared and divergent religious perceptions, leading to a significant transformation in the analysand's religious experience.

  10. Predictors of influenza a molecular viral shedding in Hutterite communities.

    PubMed

    Wang, Biao; Russell, Margaret L; Fonseca, Kevin; Earn, David J D; Horsman, Gregory; Van Caeseele, Paul; Chokani, Khami; Vooght, Mark; Babiuk, Lorne; Walter, Stephen D; Loeb, Mark

    2017-05-01

    Patterns of influenza molecular viral shedding following influenza infection have been well established; predictors of viral shedding however remain uncertain. We sought to determine factors associated with peak molecular viral load, duration of shedding, and viral area under the curve (AUC) in children and adult Hutterite colony members with laboratory-confirmed influenza. A cohort study was conducted in Hutterite colonies in Alberta, Canada. Flocked nasal swabs were collected during three influenza seasons (2007-2008 to 2009-2010) from both symptomatic and asymptomatic individuals infected with influenza. Samples were tested by real-time reverse-transcription polymerase chain reaction for influenza A and influenza B, and the viral load was determined for influenza A-positive samples. For seasonal H1N1, younger age was associated with a larger AUC, female sex was associated with decreased peak viral load and reduced viral shedding duration, while the presence of comorbidity was associated with increased peak viral load. For H3N2, younger age was associated with increased peak viral load and increased AUC. For pandemic H1N1, younger age was associated with increased peak viral load and increased viral AUC, female sex was associated with reduced peak viral load, while inapparent infection was associated with reduced peak viral load, reduced viral shedding duration, and reduced viral AUC. Patterns of molecular viral shedding vary by age, sex, comorbidity, and the presence of symptoms. Predictor variables vary by influenza A subtype. © 2017 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  11. HydroSHEDS: A global comprehensive hydrographic dataset

    NASA Astrophysics Data System (ADS)

    Wickel, B. A.; Lehner, B.; Sindorf, N.

    2007-12-01

    The Hydrological data and maps based on SHuttle Elevation Derivatives at multiple Scales (HydroSHEDS) is an innovative product that, for the first time, provides hydrographic information in a consistent and comprehensive format for regional and global-scale applications. HydroSHEDS offers a suite of geo-referenced data sets, including stream networks, watershed boundaries, drainage directions, and ancillary data layers such as flow accumulations, distances, and river topology information. The goal of developing HydroSHEDS was to generate key data layers to support regional and global watershed analyses, hydrological modeling, and freshwater conservation planning at a quality, resolution and extent that had previously been unachievable. Available resolutions range from 3 arc-second (approx. 90 meters at the equator) to 5 minute (approx. 10 km at the equator) with seamless near-global extent. HydroSHEDS is derived from elevation data of the Shuttle Radar Topography Mission (SRTM) at 3 arc-second resolution. The original SRTM data have been hydrologically conditioned using a sequence of automated procedures. Existing methods of data improvement and newly developed algorithms have been applied, including void filling, filtering, stream burning, and upscaling techniques. Manual corrections were made where necessary. Preliminary quality assessments indicate that the accuracy of HydroSHEDS significantly exceeds that of existing global watershed and river maps. HydroSHEDS was developed by the Conservation Science Program of the World Wildlife Fund (WWF) in partnership with the U.S. Geological Survey (USGS), the International Centre for Tropical Agriculture (CIAT), The Nature Conservancy (TNC), and the Center for Environmental Systems Research (CESR) of the University of Kassel, Germany.

  12. On aerodynamic noise generation from vortex shedding in rotating blades

    NASA Astrophysics Data System (ADS)

    Martin, B. T.; Bies, D. A.

    1992-06-01

    The interaction of the shed wakes of plates in a cascade with each following plate is investigated in a water tunnel and shown to provide an explanation for an observed very powerful aerodynamic noise source. In particular, the noise generation of an idling circular saw may be explained as due to the interaction of the wake shed by an upstream tooth with the leading edge of the following downstream tooth. When a vortex travelling downstream in the gullet between teeth encounters the leading edge of the downstream tooth it is deflected out of the gullet into the main stream. The associated impulses which the teeth encounter give rise to the radiated noise.

  13. Distributed Load Shedding over Directed Communication Networks with Time Delays

    SciTech Connect

    Yang, Tao; Wu, Di

    2016-07-25

    When generation is insufficient to support all loads under emergencies, effective and efficient load shedding needs to be deployed in order to maintain the supply-demand balance. This paper presents a distributed load shedding algorithm, which makes efficient decision based on the discovered global information. In the global information discovery process, each load only communicates with its neighboring load via directed communication links possibly with arbitrarily large but bounded time varying communication delays. We propose a novel distributed information discovery algorithm based on ratio consensus. Simulation results are used to validate the proposed method.

  14. Nonlinear modelling of vortex shedding control in cylinder wakes

    NASA Astrophysics Data System (ADS)

    Roussopoulos, Kimon; Monkewitz, Peter A.

    Kármán vortex shedding behind a cylinder placed at right angles to a uniform flow is known to be a limit cycle oscillation that results from the saturation of a global instability of the wake flow. In this paper we study the feedback control of Kármán vortex shedding for Reynolds numbers (based on cylinder diameter) close to the critical value of Re c ≈ 47 using “single input - single output” (SISO) proportional control. A model is presented that combines the linear streamwise global mode amplitude equation and the nonlinear spanwise Ginzburg-Landau equation and correctly models the three-dimensional effects observed in the controlled wake of finite length cyclinders. In particular it is demonstrated that for long cylinders vortex shedding can only be suppressed at the spanwise location of the sensor even though the actuation occurs uniformly over the entire span. At a fixed streamwise position the spanwise variation of the shedding angle is thereby given by the “hole solution” of Nozaki and Bekki, J. Phys. Soc. Jpn. 53 (1984) 1581.

  15. Evaluation of the shedding potential of textile materials.

    PubMed

    De Wael, K; Lepot, L; Lunstroot, K; Gason, F

    2010-12-01

    A practical method is proposed to assess the shedding potential of textile materials. The evaluation of the sheddability is based on the use of adhesive tapes and on comparison, using three different sheddability scales for cotton, wool and fine man-made fibres.

  16. Older Men as Learners: Irish Men's Sheds as an Intervention

    ERIC Educational Resources Information Center

    Carragher, Lucia; Golding, Barry

    2015-01-01

    To date, little attention has been placed on older men (aged 50+ years) as learners, with much of the literature on adult learning concerned with younger age-groups and issues around gender equity directed mainly at women. This article examines the impact of community-based men's sheds on informal and nonformal learning by older men in Ireland. It…

  17. USEPA SHEDS MODEL: METHODOLOGY FOR EXPOSURE ASSESSMENT FOR WOOD PRESERVATIVES

    EPA Science Inventory

    A physically-based, Monte Carlo probabilistic model (SHEDS-Wood: Stochastic Human Exposure and Dose Simulation model for wood preservatives) has been applied to assess the exposure and dose of children to arsenic (As) and chromium (Cr) from contact with chromated copper arsenat...

  18. 58. LOOKING WEST AT EAST END OF LUMBERSTORAGE SHED AS ...

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

    58. LOOKING WEST AT EAST END OF LUMBER-STORAGE SHED AS TWO FORKLIFTS CARRY STACK OF LONGEST TIMBERS CUT BY HULL-OAKES LUMBER CO. PHOTOGRAPHER: UNKNOWN. DATE: 1959. COURTESY OF RALPH HULL. - Hull-Oakes Lumber Company, 23837 Dawson Road, Monroe, Benton County, OR

  19. 5. VIEW OF CABLE SHED AND CABLE TRAY EMANATING FROM ...

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

    5. VIEW OF CABLE SHED AND CABLE TRAY EMANATING FROM SOUTH FACE OF LAUNCH OPERATIONS BUILDING. MICROWAVE DISH IN FOREGROUND. METEOROLOGICAL TOWER IN BACKGROUND. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  20. 5. Close up view of shed which houses the 1932 ...

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

    5. Close up view of shed which houses the 1932 turbine. Shaft in foreground was part of a power transmission system providing power to a small industrial complex at the site of the Whitney Armory. - Lake Whitney Water Filtration Plant, Lake Whitney Dam, East side of Whitney Avenue near intersection with Armory Street, Hamden, New Haven County, CT

  1. 6. View to north along dirt lane. Log shed (HABS ...

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

    6. View to north along dirt lane. Log shed (HABS No. VA-1290-N) at left, log dogtrot tenant house (HABS No. VA-1290-Q) in distance at end of lane. - Edgewood Farm, West side of State Route 600, .8 mile north of State Route 778, Clover, Halifax County, VA

  2. Older Men as Learners: Irish Men's Sheds as an Intervention

    ERIC Educational Resources Information Center

    Carragher, Lucia; Golding, Barry

    2015-01-01

    To date, little attention has been placed on older men (aged 50+ years) as learners, with much of the literature on adult learning concerned with younger age-groups and issues around gender equity directed mainly at women. This article examines the impact of community-based men's sheds on informal and nonformal learning by older men in Ireland. It…

  3. 4. VIEW OF CABLE SHED AND CABLE TRAY EMANATING FROM ...

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

    4. VIEW OF CABLE SHED AND CABLE TRAY EMANATING FROM NORTH FACE OF LAUNCH OPERATIONS BUILDING. TOPS OF BUNKER PERISCOPE AND FLAGPOLE ON ROOF OF LAUNCH OPERATIONS BUILDING IN BACKGROUND - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  4. Geometric Perturbations and Asymmetric vortex shedding About Slender Pointed Bodies

    NASA Technical Reports Server (NTRS)

    Murman, Scott M.; Kwak, Dochan (Technical Monitor)

    2000-01-01

    The flow about slender, pointed bodies can be characterized by different states with angle of attack. At moderate-to-high angles of attack (alpha approximately equals 40deg), a steady, asymmetric vortex pattern develops along the body, leading to a net lateral force. At higher angles of attack (alpha approximately equals 60deg), the aft-end of the body develops an unsteady von Karman shedding. As the angle of attack approaches 90deg, the entire body length exhibits a time-dependent vortex shedding pattern. The current work uses three-dimensional, thin-layer Navier-Stokes simulations to investigate the physical mechanisms of asymmetric vortex shedding at alpha = 40deg and alpha = 60deg. The development of an asymmetric vortex pattern via a convective instability mechanism is investigated using tip bumps, surface roughness, and tip curvature. It's found that surface roughness simulations can incite an asymmetric vortex state at alpha = 60deg which is consistent with the application of a tip bumps, and the experimentally observed flowfield. The unsteady von Karman vortex shedding on the aft portion of the body is also well resolved. The use of surface roughness did not incite a flow asymmetry at alpha = 40deg, and it was necessary to simulate tip curvature at this angle of attack in order to generate an asymmetric vortex state.

  5. Geometric Perturbations and Asymmetric Vortex Shedding about Slender Pointed Bodies

    NASA Technical Reports Server (NTRS)

    Murman, Scott M.

    2000-01-01

    The flow about slender, pointed bodies can be characterized by different states with angle of attack. At moderate-to-high angles of attack (alpha approx. = 40 deg.), a steady, asymmetric vortex pattern develops along the body, leading to a net lateral force. At higher angles of attack (alpha approx. = 60 deg.), the aft-end of the body develops an unsteady von Karman shedding. As the angle of attack approaches 90 deg., the entire body length exhibits a time-dependent vortex shedding pattern. The current work uses three-dimensional, thin-layer Navier-Stokes simulations to investigate the physical mechanisms of asymmetric vortex shedding at alpha = 40 deg. and alpha = 60 deg. The development of an asymmetric vortex pattern via a convective instability mechanism is investigated using tip bumps, surface roughness, and tip curvature. It's found that surface roughness simulations can incite an asymmetric vortex state at alpha = 60 deg. which is consistent with the application of a tip bump, and the experimentally observed flowfield. The unsteady von Karman vortex shedding on the aft. portion of the body is also well resolved. The use of surface roughness did not incite a flow asymmetry at alpha = 40 deg., and it was necessary to simulate tip curvature at this angle of attack in order to generate an asymmetric vortex state.

  6. Detail of old rain shed (Building No. 43) showing northeast ...

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

    Detail of old rain shed (Building No. 43) showing northeast wall and gutter boxes. Two 750,000 gallon steel tanks at right (T19 in foreground with T18 behind). - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  7. 38. DETAIL OF RUINS OF CYANIDE MIXING AND EXTRACTION SHED, ...

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

    38. DETAIL OF RUINS OF CYANIDE MIXING AND EXTRACTION SHED, LOOKING SOUTHEAST. CYANIDE SOLUTION WAS PREPARED HERE AND PUMPED UP INTO THE PROCESSING TANKS, AND THE PREGNANT SOLUTION WAS ALSO EXTRACTED HERE AFTER THE LEACHING PROCESS WAS COMPLETE - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA

  8. 5. Log calving barn (center), loafing shed (right of center), ...

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

    5. Log calving barn (center), loafing shed (right of center), and wood-frame garage (far right). View to southwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

  9. 16. Forge building and fuel storage shed from the southwest, ...

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

    16. Forge building and fuel storage shed from the southwest, c.1918 Photocopied from a photograph in the collection of William F. Applegate, 43 Grandview Avenue, Wallingford, Connecticut. - Eli Whitney Armory, West of Whitney Avenue, Armory Street Vicinity, Hamden, New Haven County, CT

  10. A POPULATION EXPOSURE MODEL FOR PARTICULATE MATTER: SHEDS-PM

    EPA Science Inventory

    The US EPA National Exposure Research Laboratory (NERL) has developed a population exposure and dose model for particulate matter (PM) that will be publicly available in Fall 2002. The Stochastic Human Exposure and Dose Simulation (SHEDS-PM) model uses a probabilistic approach ...

  11. Organochlorine detection in the shed skins of snakes.

    PubMed

    Jones, D E; Gogal, R M; Nader, P B; Holladay, S D

    2005-03-01

    Lizards and snakes eliminate heavy metals in their shed skins. There are no data with regard to reptilian skin as a depuration route for organochlorine (OC) compounds; however, birds deposit OCs in feathers. Corn snakes (Elaphe guttata) were therefore fed thawed mice that had been injected with a mixture of alpha-chlordane, Aroclor 1254 (a polychlorinated biphenyl (PCB) mixture), and lindane (gamma-hexachlorocyclohexane) at 2, 8, and 4 mg/kg, respectively. Feeding of contaminated mice occurred on the first weekly feeding of each month, with remaining weekly feedings consisting of noncontaminated mice, and was continued for 6 months. Shed skins were evaluated in a multiresidue OC scan by gas chromatography. All three chemical contaminants were readily detected in the shed skins: chlordane, 0.155-0.213 ppm; PCB, 3.49-7.01 ppm; lindane: 0.028-0.042 ppm. These data suggest that the shed skin of snakes may serve as an elimination route for OC contaminants and as such may have utility as a noninvasive, nondestructive indicator tissue for assessing environmental contamination.

  12. 11. VIEW SHOWING THE SUPERSTRUCTURE OF THE SHED ROOF (REMOVED ...

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

    11. VIEW SHOWING THE SUPERSTRUCTURE OF THE SHED ROOF (REMOVED AUTUMN OF 1996) PROTECTING THE PRESENT INTAKE GATES- AND RAKE-LIFTING MECHANISMS AND THE TRASH RACKS (LOWER FOREGROUND), LOOKING NORTH. - Washington Water Power Company Post Falls Power Plant, Middle Channel Powerhouse & Dam, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

  13. Shedding of Water Drops from a Surface under Icing Conditions.

    PubMed

    Mandal, Deepak Kumar; Criscione, Antonio; Tropea, C; Amirfazli, A

    2015-09-01

    A sessile water drop exposed to an air flow will shed if the adhesion is overcome by the external aerodynamic forces on the drop. In this study, shedding of water drops were investigated under icing conditions, on surfaces with different wettabilities, from hydrophilic to superhydrophobic. A wind tunnel was used for experiments in a temperature range between -8 and 24.5 °C. Results indicate that the temperature has a major influence on the incipient motion of drop shedding. The critical air velocity (U(c)) at which a drop first starts to shed generally increases under icing conditions, indicating an increase in the adhesion force. The contact angle hysteresis (CAH) and the drop base length (L(b)) are found to be the controlling factors for adhesion. A correlation was also developed to deduce the drag coefficient, C(D) for the drop. It was found that C(D) can decrease under icing conditions. In general, a lower C(D) and higher adhesion together lead to a higher critical air velocity. However, there are systems such as water on Teflon for which the critical air velocity remains practically unaffected by temperature because of similar adhesion and C(D) values, at all temperatures tested.

  14. Circulation shedding in viscous starting flow past a flat plate

    NASA Astrophysics Data System (ADS)

    Nitsche, Monika; Xu, Ling

    2014-12-01

    Numerical simulations of viscous flow past a flat plate moving in the direction normal to itself reveal details of the vortical structure of the flow. At early times, most of the vorticity is attached to the plate. This paper introduces a definition of the shed circulation at all times and shows that it indeed represents vorticity that separates and remains separated from the plate. During a large initial time period, the shed circulation satisfies the scaling laws predicted for self-similar inviscid separation. Various contributions to the circulation shedding rate are presented. The results show that during this initial time period, viscous diffusion of vorticity out of the vortex is significant but appears to be independent of the value of the Reynolds number. At later times, the departure of the shed circulation from its large Reynolds number behaviour is significantly affected by diffusive loss of vorticity through the symmetry axis. A timescale is proposed that describes when the viscous loss through the axis becomes relevant. The simulations provide benchmark results to evaluate simpler separation models such as point vortex and vortex sheet models. A comparison with vortex sheet results is included.

  15. 38. East elevation of coffee storage and drying shed with ...

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

    38. East elevation of coffee storage and drying shed with circular, cattle watering pond in left foreground and coffee mill in background right. HAER PR, 6-MAGU, 1C-1 - Hacienda Buena Vista, PR Route 10 (Ponce to Arecibo), Magueyes, Ponce Municipio, PR

  16. 3. VIEW OF NORTHEAST ELEVATION AND 19061010 ONESTORY SHED ADDITION ...

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

    3. VIEW OF NORTHEAST ELEVATION AND 1906-1010 ONE-STORY SHED ADDITION AT LEFT; NORTHWEST ELEVATION AND PARKING AREA AT RIGHT; PARKING AREA WAS SITE OF FORMER STOREHOUSE 'A' AND 'B'; LANE AT LEFT IS NORTH DRIVEWAY, BUILT CA. 1935 - Massachusetts Mills, Cloth Room-Section 15, 95 Bridge Street, Lowell, Middlesex County, MA

  17. A Robust Load Shedding Strategy for Microgrid Islanding Transition

    SciTech Connect

    Liu, Guodong; Xiao, Bailu; Starke, Michael R; Ceylan, Oguzhan; Tomsovic, Kevin

    2016-01-01

    A microgrid is a group of interconnected loads and distributed energy resources. It can operate in either gridconnected mode to exchange energy with the main grid or run autonomously as an island in emergency mode. However, the transition of microgrid from grid-connected mode to islanded mode is usually associated with excessive load (or generation), which should be shed (or spilled). Under this condition, this paper proposes an robust load shedding strategy for microgrid islanding transition, which takes into account the uncertainties of renewable generation in the microgrid and guarantees the balance between load and generation after islanding. A robust optimization model is formulated to minimize the total operation cost, including fuel cost and penalty for load shedding. The proposed robust load shedding strategy works as a backup plan and updates at a prescribed interval. It assures a feasible operating point after islanding given the uncertainty of renewable generation. The proposed algorithm is demonstrated on a simulated microgrid consisting of a wind turbine, a PV panel, a battery, two distributed generators (DGs), a critical load and a interruptible load. Numerical simulation results validate the proposed algorithm.

  18. 12. VIEW OF (PRESUMED) OUTHOUSE SHED. DOOR HAS AN AIR ...

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

    12. VIEW OF (PRESUMED) OUTHOUSE SHED. DOOR HAS AN AIR FORCE INSIGNIA EMBLEM AFFIXED, 'AIR FORCE WEAPONS LABORATORY.' OTHER SIGN ON DOOR SAYS, 'BSD LIASON OFFICE.' INEL PHOTO NUMBER 65-6173, TAKEN NOVEMBER 10, 1965. - Idaho National Engineering Laboratory, Advanced Reentry Vehicle Fusing System, Scoville, Butte County, ID

  19. 13. OVERALL SOUTH ELEVATION FROM STORAGE SHED D, SHOWING SHOP ...

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

    13. OVERALL SOUTH ELEVATION FROM STORAGE SHED D, SHOWING SHOP A, CRANE, SIGN STRUCTURE, AND WATER TOWER. NOTE TOWERS OF BRIDGE BEHIND PLANT. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  20. Heritage Conservation in the "Back Shed" of the Learning City.

    ERIC Educational Resources Information Center

    Boshier, Roger

    2003-01-01

    Describes Back Shed, a group of New Zealand heritage conservationists who center their work in lifelong learning. Situates their activities in the context of the learning city, a community development concept that mobilizes learning resources across many sectors. Discusses heritage conservation as a process of meaning making. (Contains 29…