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Sample records for stabilizes stalled forks

  1. PTEN Regulates DNA Replication Progression and Stalled Fork Recovery

    Science.gov (United States)

    He, Jinxue; Kang, Xi; Yin, Yuxin; Chao, K.S. Clifford; Shen, Wen H.

    2015-01-01

    Faithful DNA replication is a cornerstone of genomic integrity. PTEN plays multiple roles in genome protection and tumor suppression. Here we report on the importance of PTEN in DNA replication. PTEN depletion leads to impairment of replication progression and stalled fork recovery, indicating an elevation of endogenous replication stress. Exogenous replication inhibition aggravates replication-originated DNA lesions without inducing S-phase arrest in cells lacking PTEN, representing replication stress tolerance. Our analysis reveals the physical association of PTEN with DNA replication forks and PTEN-dependent recruitment of Rad51. PTEN deletion results in Rad51 dissociation from replication forks. Stalled replication forks in Pten null cells can be reactivated by ectopic Rad51 or PTEN, the latter facilitating chromatin loading of Rad51. These data highlight the interplay of PTEN with Rad51 in promoting stalled fork restart. We propose that loss of PTEN may initiate a replication stress cascade that progressively deteriorates through the cell cycle. PMID:26158445

  2. FBH1 Catalyzes Regression of Stalled Replication Forks

    DEFF Research Database (Denmark)

    Fugger, Kasper; Mistrik, Martin; Neelsen, Kai J

    2015-01-01

    DNA replication fork perturbation is a major challenge to the maintenance of genome integrity. It has been suggested that processing of stalled forks might involve fork regression, in which the fork reverses and the two nascent DNA strands anneal. Here, we show that FBH1 catalyzes regression......, is required for early phosphorylation of ATM substrates such as CHK2 and CtIP as well as hyperphosphorylation of RPA. These phosphorylations occur prior to apparent DNA double-strand break formation. Furthermore, FBH1-dependent signaling promotes checkpoint control and preserves genome integrity. We propose...

  3. 14-3-3 Proteins regulate exonuclease 1-dependent processing of stalled replication forks.

    Directory of Open Access Journals (Sweden)

    Kim Engels

    2011-04-01

    Full Text Available Replication fork integrity, which is essential for the maintenance of genome stability, is monitored by checkpoint-mediated phosphorylation events. 14-3-3 proteins are able to bind phosphorylated proteins and were shown to play an undefined role under DNA replication stress. Exonuclease 1 (Exo1 processes stalled replication forks in checkpoint-defective yeast cells. We now identify 14-3-3 proteins as in vivo interaction partners of Exo1, both in yeast and mammalian cells. Yeast 14-3-3-deficient cells fail to induce Mec1-dependent Exo1 hyperphosphorylation and accumulate Exo1-dependent ssDNA gaps at stalled forks, as revealed by electron microscopy. This leads to persistent checkpoint activation and exacerbated recovery defects. Moreover, using DNA bi-dimensional electrophoresis, we show that 14-3-3 proteins promote fork progression under limiting nucleotide concentrations. We propose that 14-3-3 proteins assist in controlling the phosphorylation status of Exo1 and additional unknown targets, promoting fork progression, stability, and restart in response to DNA replication stress.

  4. ETAA1 acts at stalled replication forks to maintain genome integrity

    Science.gov (United States)

    Bass, Thomas E.; Luzwick, Jessica W.; Kavanaugh, Gina; Carroll, Clinton; Dungrawala, Huzefa; Glick, Gloria G.; Feldkamp, Michael D.; Putney, Reid; Chazin, Walter J.; Cortez, David

    2017-01-01

    The ATR checkpoint kinase coordinates cellular responses to DNA replication stress. Budding yeast contain three activators of Mec1 (the ATR orthologue); however, only TOPBP1 is known to activate ATR in vertebrates. We identified ETAA1 as a replication stress response protein in two proteomic screens. ETAA1-deficient cells accumulate double-strand breaks, sister chromatid exchanges, and other hallmarks of genome instability. They are also hyper-sensitive to replication stress and have increased frequencies of replication fork collapse. ETAA1 contains two RPA-interaction motifs that localize ETAA1 to stalled replication forks. It also interacts with several DNA damage response proteins including the BLM/TOP3α/RMI1/RMI2 and ATR/ATRIP complexes. It binds ATR/ATRIP directly using a motif with sequence similarity to the TOPBP1-ATR activation domain; and like TOPBP1, ETAA1 acts as a direct ATR activator. ETAA1 functions in parallel to the TOPBP1/RAD9/HUS1/RAD1 pathway to regulate ATR and maintain genome stability. Thus, vertebrate cells contain at least two ATR activating proteins. PMID:27723720

  5. Airfoil stall interpreted through linear stability analysis

    Science.gov (United States)

    Busquet, Denis; Juniper, Matthew; Richez, Francois; Marquet, Olivier; Sipp, Denis

    2017-11-01

    Although airfoil stall has been widely investigated, the origin of this phenomenon, which manifests as a sudden drop of lift, is still not clearly understood. In the specific case of static stall, multiple steady solutions have been identified experimentally and numerically around the stall angle. We are interested here in investigating the stability of these steady solutions so as to first model and then control the dynamics. The study is performed on a 2D helicopter blade airfoil OA209 at low Mach number, M 0.2 and high Reynolds number, Re 1.8 ×106 . Steady RANS computation using a Spalart-Allmaras model is coupled with continuation methods (pseudo-arclength and Newton's method) to obtain steady states for several angles of incidence. The results show one upper branch (high lift), one lower branch (low lift) connected by a middle branch, characterizing an hysteresis phenomenon. A linear stability analysis performed around these equilibrium states highlights a mode responsible for stall, which starts with a low frequency oscillation. A bifurcation scenario is deduced from the behaviour of this mode. To shed light on the nonlinear behavior, a low order nonlinear model is created with the same linear stability behavior as that observed for that airfoil.

  6. Histone H2B mono-ubiquitylation maintains genomic integrity at stalled replication forks

    Science.gov (United States)

    Northam, Matthew R.; Trujillo, Kelly M.

    2016-01-01

    Histone modifications play an important role in regulating access to DNA for transcription, DNA repair and DNA replication. A central player in these events is the mono-ubiquitylation of histone H2B (H2Bub1), which has been shown to regulate nucleosome dynamics. Previously, it was shown that H2Bub1 was important for nucleosome assembly onto nascent DNA at active replication forks. In the absence of H2Bub1, incomplete chromatin structures resulted in several replication defects. Here, we report new evidence, which shows that loss of H2Bub1 contributes to genomic instability in yeast. Specifically, we demonstrate that H2Bub1-deficient yeast accumulate mutations at a high frequency under conditions of replicative stress. This phenotype is due to an aberrant DNA Damage Tolerance (DDT) response upon fork stalling. We show that H2Bub1 normally functions to promote error-free translesion synthesis (TLS) mediated by DNA polymerase eta (Polη). Without H2Bub1, DNA polymerase zeta (Polζ) is responsible for a highly mutagenic alternative mechanism. While H2Bub1 does not appear to regulate other DDT pathways, error-free DDT mechanisms are employed by H2Bub1-deficient cells as another means for survival. However, in these instances, the anti-recombinase, Srs2, is essential to prevent the accumulation of toxic HR intermediates that arise in an unconstrained chromatin environment. PMID:27458205

  7. Replication fork stability confers chemoresistance in BRCA-deficient cells

    DEFF Research Database (Denmark)

    Chaudhuri, Arnab Ray; Callen, Elsa; Ding, Xia

    2016-01-01

    /4 complex protein, PTIP, protects Brca1/2-deficient cells from DNA damage and rescues the lethality of Brca2-deficient embryonic stem cells. However, PTIP deficiency does not restore homologous recombination activity at double-strand breaks. Instead, its absence inhibits the recruitment of the MRE11......Cells deficient in the Brca1 and Brca2 genes have reduced capacity to repair DNA double-strand breaks by homologous recombination and consequently are hypersensitive to DNA-damaging agents, including cisplatin and poly(ADP-ribose) polymerase (PARP) inhibitors. Here we show that loss of the MLL3...... nuclease to stalled replication forks, which in turn protects nascent DNA strands from extensive degradation. More generally, acquisition of PARP inhibitors and cisplatin resistance is associated with replication fork protection in Brca2-deficient tumour cells that do not develop Brca2 reversion mutations...

  8. Phenotypes of dnaXE145A Mutant Cells Indicate that the Escherichia coli Clamp Loader Has a Role in the Restart of Stalled Replication Forks.

    Science.gov (United States)

    Flåtten, Ingvild; Helgesen, Emily; Pedersen, Ida Benedikte; Waldminghaus, Torsten; Rothe, Christiane; Taipale, Riikka; Johnsen, Line; Skarstad, Kirsten

    2017-12-15

    The Escherichia coli dnaX E145A mutation was discovered in connection with a screen for multicopy suppressors of the temperature-sensitive topoisomerase IV mutation parE10 The gene for the clamp loader subunits τ and γ, dnaX , but not the mutant dnaX E145A , was found to suppress parE10 (Ts) when overexpressed. Purified mutant protein was found to be functional in vitro , and few phenotypes were found in vivo apart from problems with partitioning of DNA in rich medium. We show here that a large number of the replication forks that initiate at oriC never reach the terminus in dnaX E145A mutant cells. The SOS response was found to be induced, and a combination of the dnaX E145A mutation with recBC and recA mutations led to reduced viability. The mutant cells exhibited extensive chromosome fragmentation and degradation upon inactivation of recBC and recA , respectively. The results indicate that the dnaX E145A mutant cells suffer from broken replication forks and that these need to be repaired by homologous recombination. We suggest that the dnaX -encoded τ and γ subunits of the clamp loader, or the clamp loader complex itself, has a role in the restart of stalled replication forks without extensive homologous recombination. IMPORTANCE The E. coli clamp loader complex has a role in coordinating the activity of the replisome at the replication fork and loading β-clamps for lagging-strand synthesis. Replication forks frequently encounter obstacles, such as template lesions, secondary structures, and tightly bound protein complexes, which will lead to fork stalling. Some pathways of fork restart have been characterized, but much is still unknown about the actors and mechanisms involved. We have in this work characterized the dnaX E145A clamp loader mutant. We find that the naturally occurring obstacles encountered by a replication fork are not tackled in a proper way by the mutant clamp loader and suggest a role for the clamp loader in the restart of stalled

  9. Nuclear insulin-like growth factor 1 receptor phosphorylates proliferating cell nuclear antigen and rescues stalled replication forks after DNA damage.

    Science.gov (United States)

    Waraky, Ahmed; Lin, Yingbo; Warsito, Dudi; Haglund, Felix; Aleem, Eiman; Larsson, Olle

    2017-11-03

    We have previously shown that the insulin-like growth factor 1 receptor (IGF-1R) translocates to the cell nucleus, where it binds to enhancer-like regions and increases gene transcription. Further studies have demonstrated that nuclear IGF-1R (nIGF-1R) physically and functionally interacts with some nuclear proteins, i.e. the lymphoid enhancer-binding factor 1 (Lef1), histone H3, and Brahma-related gene-1 proteins. In this study, we identified the proliferating cell nuclear antigen (PCNA) as a nIGF-1R-binding partner. PCNA is a pivotal component of the replication fork machinery and a main regulator of the DNA damage tolerance (DDT) pathway. We found that IGF-1R interacts with and phosphorylates PCNA in human embryonic stem cells and other cell lines. In vitro MS analysis of PCNA co-incubated with the IGF-1R kinase indicated tyrosine residues 60, 133, and 250 in PCNA as IGF-1R targets, and PCNA phosphorylation was followed by mono- and polyubiquitination. Co-immunoprecipitation experiments suggested that these ubiquitination events may be mediated by DDT-dependent E2/E3 ligases ( e.g. RAD18 and SHPRH/HLTF). Absence of IGF-1R or mutation of Tyr-60, Tyr-133, or Tyr-250 in PCNA abrogated its ubiquitination. Unlike in cells expressing IGF-1R, externally induced DNA damage in IGF-1R-negative cells caused G 1 cell cycle arrest and S phase fork stalling. Taken together, our results suggest a role of IGF-1R in DDT. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  10. RADX interacts with single-stranded DNA to promote replication fork stability

    DEFF Research Database (Denmark)

    Schubert, Lisa; Ho, Teresa; Hoffmann, Saskia

    2017-01-01

    has an essential genome maintenance role, protecting ssDNA regions from nucleolytic degradation and providing a recruitment platform for proteins involved in responses to replication stress and DNA damage. Here, we identify the uncharacterized protein RADX (CXorf57) as an ssDNA-binding factor in human...... cells. RADX binds ssDNA via an N-terminal OB fold cluster, which mediates its recruitment to sites of replication stress. Deregulation of RADX expression and ssDNA binding leads to enhanced replication fork stalling and degradation, and we provide evidence that a balanced interplay between RADX and RPA...

  11. FANCJ couples replication past natural fork barriers with maintenance of chromatin structure.

    Science.gov (United States)

    Schwab, Rebekka A; Nieminuszczy, Jadwiga; Shin-ya, Kazuo; Niedzwiedz, Wojciech

    2013-04-01

    Defective DNA repair causes Fanconi anemia (FA), a rare childhood cancer-predisposing syndrome. At least 15 genes are known to be mutated in FA; however, their role in DNA repair remains unclear. Here, we show that the FANCJ helicase promotes DNA replication in trans by counteracting fork stalling on replication barriers, such as G4 quadruplex structures. Accordingly, stabilization of G4 quadruplexes in ΔFANCJ cells restricts fork movements, uncouples leading- and lagging-strand synthesis and generates small single-stranded DNA gaps behind the fork. Unexpectedly, we also discovered that FANCJ suppresses heterochromatin spreading by coupling fork movement through replication barriers with maintenance of chromatin structure. We propose that FANCJ plays an essential role in counteracting chromatin compaction associated with unscheduled replication fork stalling and restart, and suppresses tumorigenesis, at least partially, in this replication-specific manner.

  12. PTEN regulates RPA1 and protects DNA replication forks

    Science.gov (United States)

    Wang, Guangxi; Li, Yang; Wang, Pan; Liang, Hui; Cui, Ming; Zhu, Minglu; Guo, Limei; Su, Qian; Sun, Yujie; McNutt, Michael A; Yin, Yuxin

    2015-01-01

    Tumor suppressor PTEN regulates cellular activities and controls genome stability through multiple mechanisms. In this study, we report that PTEN is necessary for the protection of DNA replication forks against replication stress. We show that deletion of PTEN leads to replication fork collapse and chromosomal instability upon fork stalling following nucleotide depletion induced by hydroxyurea. PTEN is physically associated with replication protein A 1 (RPA1) via the RPA1 C-terminal domain. STORM and iPOND reveal that PTEN is localized at replication sites and promotes RPA1 accumulation on replication forks. PTEN recruits the deubiquitinase OTUB1 to mediate RPA1 deubiquitination. RPA1 deletion confers a phenotype like that observed in PTEN knockout cells with stalling of replication forks. Expression of PTEN and RPA1 shows strong correlation in colorectal cancer. Heterozygous disruption of RPA1 promotes tumorigenesis in mice. These results demonstrate that PTEN is essential for DNA replication fork protection. We propose that RPA1 is a target of PTEN function in fork protection and that PTEN maintains genome stability through regulation of DNA replication. PMID:26403191

  13. A model for roll stall and the inherent stability modes of low aspect ratio wings at low Reynolds numbers

    Science.gov (United States)

    Shields, Matt

    The development of Micro Aerial Vehicles has been hindered by the poor understanding of the aerodynamic loading and stability and control properties of the low Reynolds number regime in which the inherent low aspect ratio (LAR) wings operate. This thesis experimentally evaluates the static and damping aerodynamic stability derivatives to provide a complete aerodynamic model for canonical flat plate wings of aspect ratios near unity at Reynolds numbers under 1 x 105. This permits the complete functionality of the aerodynamic forces and moments to be expressed and the equations of motion to solved, thereby identifying the inherent stability properties of the wing. This provides a basis for characterizing the stability of full vehicles. The influence of the tip vortices during sideslip perturbations is found to induce a loading condition referred to as roll stall, a significant roll moment created by the spanwise induced velocity asymmetry related to the displacement of the vortex cores relative to the wing. Roll stall is manifested by a linearly increasing roll moment with low to moderate angles of attack and a subsequent stall event similar to a lift polar; this behavior is not experienced by conventional (high aspect ratio) wings. The resulting large magnitude of the roll stability derivative, Cl,beta and lack of roll damping, Cl ,rho, create significant modal responses of the lateral state variables; a linear model used to evaluate these modes is shown to accurately reflect the solution obtained by numerically integrating the nonlinear equations. An unstable Dutch roll mode dominates the behavior of the wing for small perturbations from equilibrium, and in the presence of angle of attack oscillations a previously unconsidered coupled mode, referred to as roll resonance, is seen develop and drive the bank angle? away from equilibrium. Roll resonance requires a linear time variant (LTV) model to capture the behavior of the bank angle, which is attributed to the

  14. Replication Stalling and Heteroduplex Formation within CAG/CTG Trinucleotide Repeats by Mismatch Repair

    KAUST Repository

    Viterbo, David

    2016-03-16

    Trinucleotide repeat expansions are responsible for at least two dozen neurological disorders. Mechanisms leading to these large expansions of repeated DNA are still poorly understood. It was proposed that transient stalling of the replication fork by the repeat tract might trigger slippage of the newly-synthesized strand over its template, leading to expansions or contractions of the triplet repeat. However, such mechanism was never formally proven. Here we show that replication fork pausing and CAG/CTG trinucleotide repeat instability are not linked, stable and unstable repeats exhibiting the same propensity to stall replication forks when integrated in a yeast natural chromosome. We found that replication fork stalling was dependent on the integrity of the mismatch-repair system, especially the Msh2p-Msh6p complex, suggesting that direct interaction of MMR proteins with secondary structures formed by trinucleotide repeats in vivo, triggers replication fork pauses. We also show by chromatin immunoprecipitation that Msh2p is enriched at trinucleotide repeat tracts, in both stable and unstable orientations, this enrichment being dependent on MSH3 and MSH6. Finally, we show that overexpressing MSH2 favors the formation of heteroduplex regions, leading to an increase in contractions and expansions of CAG/CTG repeat tracts during replication, these heteroduplexes being dependent on both MSH3 and MSH6. These heteroduplex regions were not detected when a mutant msh2-E768A gene in which the ATPase domain was mutated was overexpressed. Our results unravel two new roles for mismatch-repair proteins: stabilization of heteroduplex regions and transient blocking of replication forks passing through such repeats. Both roles may involve direct interactions between MMR proteins and secondary structures formed by trinucleotide repeat tracts, although indirect interactions may not be formally excluded.

  15. A Network of Multi-Tasking Proteins at the DNA Replication Fork Preserves Genome Stability.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available To elucidate the network that maintains high fidelity genome replication, we have introduced two conditional mutant alleles of DNA2, an essential DNA replication gene, into each of the approximately 4,700 viable yeast deletion mutants and determined the fitness of the double mutants. Fifty-six DNA2-interacting genes were identified. Clustering analysis of genomic synthetic lethality profiles of each of 43 of the DNA2-interacting genes defines a network (consisting of 322 genes and 876 interactions whose topology provides clues as to how replication proteins coordinate regulation and repair to protect genome integrity. The results also shed new light on the functions of the query gene DNA2, which, despite many years of study, remain controversial, especially its proposed role in Okazaki fragment processing and the nature of its in vivo substrates. Because of the multifunctional nature of virtually all proteins at the replication fork, the meaning of any single genetic interaction is inherently ambiguous. The multiplexing nature of the current studies, however, combined with follow-up supporting experiments, reveals most if not all of the unique pathways requiring Dna2p. These include not only Okazaki fragment processing and DNA repair but also chromatin dynamics.

  16. Pitch Fork

    DEFF Research Database (Denmark)

    Williams, Peter Leslie; Overholt, Daniel

    2017-01-01

    Pitch Fork is a prototype of an alternate, actuated digital musical instrument (DMI). It uses 5 infra-red and 4 piezoelectric sensors to control an additive synthesis engine. Iron bars are used as the physical point of contact in interaction with the aim of using this materials natural acoustic...

  17. Impediment of Replication Forks by Long Non-coding RNA Provokes Chromosomal Rearrangements by Error-Prone Restart

    Directory of Open Access Journals (Sweden)

    Takaaki Watanabe

    2017-11-01

    Full Text Available Naturally stalled replication forks are considered to cause structurally abnormal chromosomes in tumor cells. However, underlying mechanisms remain speculative, as capturing naturally stalled forks has been a challenge. Here, we captured naturally stalled forks in tumor cells and delineated molecular processes underlying the structural evolution of circular mini-chromosomes (double-minute chromosomes; DMs. Replication forks stalled on the DM by the co-directional collision with the transcription machinery for long non-coding RNA. RPA, BRCA2, and DNA polymerase eta (Polη were recruited to the stalled forks. The recruitment of Polη was critical for replication to continue, as Polη knockdown resulted in DM loss. Rescued stalled forks were error-prone and switched replication templates repeatedly to create complex fusions of multiple short genomic segments. In mice, such complex fusions circularized the genomic region surrounding MYC to create a DM during tumorigenesis. Our results define a molecular path that guides stalled replication forks to complex chromosomal rearrangements.

  18. Stalled replication forks generate a distinct mutational signature in yeast

    DEFF Research Database (Denmark)

    Larsen, Nicolai B.; Liberti, Sascha E.; Vogel, Ivan

    2017-01-01

    Proliferating cells acquire genome alterations during the act of DNA replication. This leads to mutation accumulation and somatic cell mosaicism in multicellular organisms, and is also implicated as an underlying cause of aging and tumorigenesis. The molecular mechanisms of DNA replication-associ...

  19. The Late Cretaceous Middle Fork caldera, its resurgent intrusion, and enduring landscape stability in east-central Alaska

    Science.gov (United States)

    Bacon, Charles R.; Dusel-Bacon, Cynthia; Aleinikoff, John N.; Slack, John F.

    2014-01-01

    Dissected caldera structures expose thick intracaldera tuff and, uncommonly, cogenetic shallow plutons, while remnants of correlative outflow tuffs deposited on the pre-eruption ground surface record elements of ancient landscapes. The Middle Fork caldera encompasses a 10 km × 20 km area of rhyolite welded tuff and granite porphyry in east-central Alaska, ∼100 km west of the Yukon border. Intracaldera tuff is at least 850 m thick. The K-feldspar megacrystic granite porphyry is exposed over much of a 7 km × 12 km area having 650 m of relief within the western part of the caldera fill. Sensitive high-resolution ion microprobe with reverse geometry (SHRIMP-RG) analyses of zircon from intracaldera tuff, granite porphyry, and outflow tuff yield U-Pb ages of 70.0 ± 1.2, 69.7 ± 1.2, and 71.1 ± 0.5 Ma (95% confidence), respectively. An aeromagnetic survey indicates that the tuff is reversely magnetized, and, therefore, that the caldera-forming eruption occurred in the C31r geomagnetic polarity chron. The tuff and porphyry have arc geochemical signatures and a limited range in SiO2 of 69 to 72 wt%. Although their phenocrysts differ in size and abundance, similar quartz + K-feldspar + plagioclase + biotite mineralogy, whole-rock geochemistry, and analytically indistinguishable ages indicate that the tuff and porphyry were comagmatic. Resorption of phenocrysts in tuff and porphyry suggests that these magmas formed by thermal rejuvenation of near-solidus or solidified crystal mush. A rare magmatic enclave (54% SiO2, arc geochemical signature) in the porphyry may be similar to parental magma and provides evidence of mafic magma and thermal input.

  20. Regulation of replication fork progression through histone supply and demand

    DEFF Research Database (Denmark)

    Groth, Anja; Corpet, Armelle; Cook, Adam J L

    2007-01-01

    DNA replication in eukaryotes requires nucleosome disruption ahead of the replication fork and reassembly behind. An unresolved issue concerns how histone dynamics are coordinated with fork progression to maintain chromosomal stability. Here, we characterize a complex in which the human histone c...... progression and histone supply and demand.......1 chaperone function, histone supply, and replicative unwinding of DNA in chromatin. We propose that Asf1, as a histone acceptor and donor, handles parental and new histones at the replication fork via an Asf1-(H3-H4)-MCM2-7 intermediate and thus provides a means to fine-tune replication fork...

  1. Homologous Recombination as a Replication Fork Escort: Fork-Protection and Recovery

    Directory of Open Access Journals (Sweden)

    Audrey Costes

    2012-12-01

    Full Text Available Homologous recombination is a universal mechanism that allows DNA repair and ensures the efficiency of DNA replication. The substrate initiating the process of homologous recombination is a single-stranded DNA that promotes a strand exchange reaction resulting in a genetic exchange that promotes genetic diversity and DNA repair. The molecular mechanisms by which homologous recombination repairs a double-strand break have been extensively studied and are now well characterized. However, the mechanisms by which homologous recombination contribute to DNA replication in eukaryotes remains poorly understood. Studies in bacteria have identified multiple roles for the machinery of homologous recombination at replication forks. Here, we review our understanding of the molecular pathways involving the homologous recombination machinery to support the robustness of DNA replication. In addition to its role in fork-recovery and in rebuilding a functional replication fork apparatus, homologous recombination may also act as a fork-protection mechanism. We discuss that some of the fork-escort functions of homologous recombination might be achieved by loading of the recombination machinery at inactivated forks without a need for a strand exchange step; as well as the consequence of such a model for the stability of eukaryotic genomes.

  2. 14 CFR 25.103 - Stall speed.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Stall speed. 25.103 Section 25.103... STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight Performance § 25.103 Stall speed. (a) The reference stall speed, VSR, is a calibrated airspeed defined by the applicant. VSR may not be less than a 1-g stall...

  3. Replisome stall events have shaped the distribution of replication origins in the genomes of yeasts

    Science.gov (United States)

    Newman, Timothy J.; Mamun, Mohammed A.; Nieduszynski, Conrad A.; Blow, J. Julian

    2013-01-01

    During S phase, the entire genome must be precisely duplicated, with no sections of DNA left unreplicated. Here, we develop a simple mathematical model to describe the probability of replication failing due to the irreversible stalling of replication forks. We show that the probability of complete genome replication is maximized if replication origins are evenly spaced, the largest inter-origin distances are minimized, and the end-most origins are positioned close to chromosome ends. We show that origin positions in the yeast Saccharomyces cerevisiae genome conform to all three predictions thereby maximizing the probability of complete replication if replication forks stall. Origin positions in four other yeasts—Kluyveromyces lactis, Lachancea kluyveri, Lachancea waltii and Schizosaccharomyces pombe—also conform to these predictions. Equating failure rates at chromosome ends with those in chromosome interiors gives a mean per nucleotide fork stall rate of ∼5 × 10−8, which is consistent with experimental estimates. Using this value in our theoretical predictions gives replication failure rates that are consistent with data from replication origin knockout experiments. Our theory also predicts that significantly larger genomes, such as those of mammals, will experience a much greater probability of replication failure genome-wide, and therefore will likely require additional compensatory mechanisms. PMID:23963700

  4. 14 CFR 25.203 - Stall characteristics.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Stall characteristics. 25.203 Section 25.203 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight Stalls § 25.203 Stall characteristics. (a) It must...

  5. SC tuning fork

    CERN Multimedia

    The tuning fork used to modulate the radiofrequency system of the synchro cyclotron (SC) from 1957 to 1973. This piece is an unused spare part. The SC was the 1st accelerator built at CERN. It operated from August 1957 until it was closed down at the end of 1990. In the SC the magnetic field did not change with time, and the particles were accelerated in successive pulses by a radiofrequency voltage of some 20kV which varied in frequency as they spiraled outwards towards the extraction radius. The frequency varied from 30MHz to about 17Mz in each pulse. The tuning fork vibrated at 55MHz in vacuum in an enclosure which formed a variable capacitor in the tuning circuit of the RF system, allowing the RF to vary over the appropriate range to accelerate protons from the centre of the macine up to 600Mev at extraction radius. In operation the tips of the tuning fork blade had an amplitude of movement of over 1 cm. The SC accelerator underwent extensive improvements from 1973 to 1975, including the installation of a...

  6. Non-catalytic Roles for XPG with BRCA1 and BRCA2 in Homologous Recombination and Genome Stability

    DEFF Research Database (Denmark)

    Trego, Kelly S.; Groesser, Torsten; Davalos, Albert R.

    2016-01-01

    about how XPG loss results in this devastating disease. We identify XPG as a partner of BRCA1 and BRCA2 in maintaining genomic stability through homologous recombination (HRR). XPG depletion causes DNA double-strand breaks, chromosomal abnormalities, cell-cycle delays, defective HRR, inability...... to overcome replication fork stalling,and replication stress. XPG directly interacts withBRCA2, RAD51, and PALB2, and XPG depletion reduces their chromatin binding and subsequent RAD51 foci formation. Upstream in HRR, XPG interacts directly with BRCA1. Its depletion causes BRCA1 hyper...

  7. New histone supply regulates replication fork speed and PCNA unloading

    DEFF Research Database (Denmark)

    Mejlvang, Jakob; Feng, Yunpeng; Alabert, Constance

    2014-01-01

    Correct duplication of DNA sequence and its organization into chromatin is central to genome function and stability. However, it remains unclear how cells coordinate DNA synthesis with provision of new histones for chromatin assembly to ensure chromosomal stability. In this paper, we show...... that replication fork speed is dependent on new histone supply and efficient nucleosome assembly. Inhibition of canonical histone biosynthesis impaired replication fork progression and reduced nucleosome occupancy on newly synthesized DNA. Replication forks initially remained stable without activation...... of conventional checkpoints, although prolonged histone deficiency generated DNA damage. PCNA accumulated on newly synthesized DNA in cells lacking new histones, possibly to maintain opportunity for CAF-1 recruitment and nucleosome assembly. Consistent with this, in vitro and in vivo analysis showed that PCNA...

  8. Investigating Stall Flutter using a DS model-An application for HAWTs

    International Nuclear Information System (INIS)

    Nichols, James; Haans, Wouter; Witcher, David; Attorni, Andrea

    2014-01-01

    As wind turbine blades become larger there is a tendency for the blade torsional stiffness to reduce, producing the possibility of dynamic instability at moderate windspeeds. While linearised methods can assess the envelope of allowable blade properties for avoiding classical flutter with attached flow aerodynamics, wind turbine aerofoils can experience stalled flow. Therefore, it is necessary to explore the possible effects of stall-flutter on blade stability. This paper aims to address methods for judging the stability of blade designs during both attached flow and stalled flow behaviour. This paper covers the following areas: i) Attached flow model A Beddoes-Leishman indicial model is presented and the choice of coefficients is explained in the context of Theodorsen's theory for flat-plate aerofoils and experimental results by Beddoes and Leishman. Special attention is given to the differing dynamic behaviour of the pitching moment due to flapping motion, pitching motion and dynamically varying inflow. (ii) Classical flutter analysis The time domain attached flow model is verified against a linear flutter analysis by comparing time domain results for a 3D model of a representative multi-megawatt turbine blade, varying the position of the centre of mass along the chord. The results show agreement to within 6% for a range of flutter onset speeds. (iii) Dynamic stall model On entering the stalled region, damping of torsional motion of an aerofoil section can become negative. A dynamic stall model which encompasses the effects of trailing edge separation and leading edge vortex detachment is presented and validated against published experimental data. (iv) Stall flutter The resulting time domain model is used in simulations validating the prediction of reduced flutter onset for stalled aerofoils. Representative stalled conditions for a multi-megawatt wind turbine blade are investigated to assess the possible reduction in flutter speed. A maximum reduction of 17

  9. Progerin sequestration of PCNA promotes replication fork collapse and mislocalization of XPA in laminopathy-related progeroid syndromes.

    Science.gov (United States)

    Hilton, Benjamin A; Liu, Ji; Cartwright, Brian M; Liu, Yiyong; Breitman, Maya; Wang, Youjie; Jones, Rowdy; Tang, Hui; Rusinol, Antonio; Musich, Phillip R; Zou, Yue

    2017-09-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder that is caused by a point mutation in the LMNA gene, resulting in production of a truncated farnesylated-prelamin A protein (progerin). We previously reported that XPA mislocalized to the progerin-induced DNA double-strand break (DSB) sites, blocking DSB repair, which led to DSB accumulation, DNA damage responses, and early replication arrest in HGPS. In this study, the XPA mislocalization to DSBs occurred at stalled or collapsed replication forks, concurrent with a significant loss of PCNA at the forks, whereas PCNA efficiently bound to progerin. This PCNA sequestration likely exposed ds-ssDNA junctions at replication forks for XPA binding. Depletion of XPA or progerin each significantly restored PCNA at replication forks. Our results suggest that although PCNA is much more competitive than XPA in binding replication forks, PCNA sequestration by progerin may shift the equilibrium to favor XPA binding. Furthermore, we demonstrated that progerin-induced apoptosis could be rescued by XPA, suggesting that XPA-replication fork binding may prevent apoptosis in HGPS cells. Our results propose a mechanism for progerin-induced genome instability and accelerated replicative senescence in HGPS.-Hilton, B. A., Liu, J., Cartwright, B. M., Liu, Y., Breitman, M., Wang, Y., Jones, R., Tang, H., Rusinol, A., Musich, P. R., Zou, Y. Progerin sequestration of PCNA promotes replication fork collapse and mislocalization of XPA in laminopathy-related progeroid syndromes. © FASEB.

  10. Clutch-Starting Stalled Research Students

    Science.gov (United States)

    Ahern, Kathy; Manathunga, Catherine

    2004-01-01

    Many research students go through periods where their research seems to stall, their motivation drops, and they seem unable to make any progress. As supervisors, we attempt to remain alert to signs that our student's progress has stalled. Drawing on cognitive strategies, this article explores a problem-solving model supervisors can use to identify…

  11. Basis for an Active Stall Avoidance System

    Directory of Open Access Journals (Sweden)

    Richard Schulze

    2000-01-01

    Full Text Available A single-stage subsonic compressor was examined with respect to compressor instabilities. During the inception of rotating stall, the transients of the pressure rise and mass flow were measured as well as their hysteresis. The development of the stall cell and the characteristics of the unstable operating range were determined.

  12. Separase prevents genomic instability by controlling replication fork speed

    Science.gov (United States)

    Cucco, Francesco; Palumbo, Elisa; Camerini, Serena; D’Alessio, Barbara; Quarantotti, Valentina; Casella, Maria Luisa; Rizzo, Ilaria Maria; Cukrov, Dubravka; Delia, Domenico; Russo, Antonella; Crescenzi, Marco

    2018-01-01

    Abstract Proper chromosome segregation is crucial for preserving genomic integrity, and errors in this process cause chromosome mis-segregation, which may contribute to cancer development. Sister chromatid separation is triggered by Separase, an evolutionary conserved protease that cleaves the cohesin complex, allowing the dissolution of sister chromatid cohesion. Here we provide evidence that Separase participates in genomic stability maintenance by controlling replication fork speed. We found that Separase interacted with the replication licensing factors MCM2–7, and genome-wide data showed that Separase co-localized with MCM complex and cohesin. Unexpectedly, the depletion of Separase increased the fork velocity about 1.5-fold and caused a strong acetylation of cohesin's SMC3 subunit and altered checkpoint response. Notably, Separase silencing triggered genomic instability in both HeLa and human primary fibroblast cells. Our results show a novel mechanism for fork progression mediated by Separase and thus the basis for genomic instability associated with tumorigenesis. PMID:29165708

  13. Construction of hydrogenation stalls for explosions

    Energy Technology Data Exchange (ETDEWEB)

    Raichle, L.

    1943-05-03

    This report contained explanations for different questions that had been asked by the Association of Chemical Manufacturers. The first item discussed was the pressure occurring in hydrogenation stalls in hydrogen explosions. The pressures actually used were much smaller than the maximum design pressure due to burning gases being allowed to escape from the top and front of the stalls since these areas were open and it could not be assumed that the whole stall space was filled with a 32% hydrogen concentration at the beginning of an explosion. The second item discussed was specifications and rules for the building of hydrogenation stalls. These included the calculations for simple wind pressure according to the Building Code with the usual safety factors and the calculations for an inner pressure of 300 kg/m/sup 2/ with the usual safety factors. An explanation of a stall explosion in Poelitz and reinforced stall construction in Poelitz were two other items that were discussed. Appendix I of the report involved maximum pressures and temperature in hydrogen explosions. Diagram I was involved with this. Appendix II discussed the behavior of a hydrogen flame at high emerging velocities and Appendix III discussed stall construction at Poelitz.

  14. The Relevance of the Dynamic Stall Effect for Transient

    DEFF Research Database (Denmark)

    Jauch, Clemens; Sørensen, Poul; Bak-Jensen, Birgitte

    2005-01-01

    This article describes a methodology to quantify the influence of dynamic stall on transient fault operations of active-stall turbines. The model of the dynamic stall effect is introduced briefly. The behaviour of the dynamic stall model during a transient fault operation is described mathematica...

  15. Biomimetic Wind Turbine Design with Lift Enhancing Periodic Stall

    NARCIS (Netherlands)

    Stamhuis, Eize Jan

    2017-01-01

    A wind turbine includes a rotor; a blade; and a periodic stall system. The periodic stall system selectively moves at least part of the blade in an oscillating motion whereby an angle of incidence continuously varies to invoke periodic stall. The periodic stall system can move the entire blade or

  16. Prediction of induced vibrations in stall

    Energy Technology Data Exchange (ETDEWEB)

    Thirstrup Petersen, J.; Thomsen, K.; Aagaard Madsen, H. [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark)

    1999-03-01

    The main results from recent research in stall induced vibrations are presented. The focus is on the edgewise blade vibrations, which during the last decade have turned out to be a potential threat against the stable operation of stall regulated wind turbines and a fact, which must be dealt with by the designer. The basic physical explanation for the phenomenon and examples of design precaution, which can be taken, are presented. (au)

  17. ATM and ATR Activities Maintain Replication Fork Integrity during SV40 Chromatin Replication

    Science.gov (United States)

    Sowd, Gregory A.; Li, Nancy Yan; Fanning, Ellen

    2013-01-01

    Mutation of DNA damage checkpoint signaling kinases ataxia telangiectasia-mutated (ATM) or ATM- and Rad3-related (ATR) results in genomic instability disorders. However, it is not well understood how the instability observed in these syndromes relates to DNA replication/repair defects and failed checkpoint control of cell cycling. As a simple model to address this question, we have studied SV40 chromatin replication in infected cells in the presence of inhibitors of ATM and ATR activities. Two-dimensional gel electrophoresis and southern blotting of SV40 chromatin replication products reveal that ATM activity prevents accumulation of unidirectional replication products, implying that ATM promotes repair of replication-associated double strand breaks. ATR activity alleviates breakage of a functional fork as it converges with a stalled fork. The results suggest that during SV40 chromatin replication, endogenous replication stress activates ATM and ATR signaling, orchestrating the assembly of genome maintenance machinery on viral replication intermediates. PMID:23592994

  18. Did mosasaurs have forked tongues?

    NARCIS (Netherlands)

    Schulp, Anne S.; Mulder, E. W. A.; Schwenk, K.

    Ever since the first mosasaur restorations were published, these extinct marine reptiles have been pictured with either notched, forked or undivided tongues. Here, we present an overview of existing iconography, a review of the previous literature, and we discuss how best to reconstruct tongue form

  19. Editorial: 3Rs tightly intertwined to maintain genome stability

    DEFF Research Database (Denmark)

    Lisby, Michael; Mortensen, Uffe H.

    2017-01-01

    , replication of damaged DNA results in stalled replication forks that await DNA damage repair before replication can be resumed. In turn, the repair of most lesions depends on processes involving DNA synthesis. At the same time, the stalled forks may engage in recombination, either as part of a controlled...... repair process or by accident, just because it can, with the risk of producing genome rearrangements and loss of heterozygosity. The set of reviews presented in this thematic issue (https://academic-oup-com.proxy.findit.dtu.dk/femsyr/pages/replication_recombination_and_repair) of FEMSYR has been selected...

  20. Plasma-based Compressor Stall Control

    Science.gov (United States)

    McGowan, Ryan; Corke, Thomas

    2017-11-01

    The use of dielectric barrier discharge (DBD) plasma actuator casing treatment to prevent or delay stall inception in an axial fan is examined. The actuators are powered by a pulsed-DC waveform which induces a larger peak velocity than a purely AC waveform such as a sine or sawtooth wave. With this system, a high-voltage DC source is supplied to both electrodes, remaining constant in time for the exposed electrode. Meanwhile, the covered electrode is periodically grounded for several microseconds and allowed to rise back to the source DC level. To test the actuators' ability to interact with and modify the formation of stall cells, a facility has been designed and constructed around nonconductive fan blades. The actuators are installed in the fan casing near the blade tips. The instrumentation allows for the measurement of rotating pressure disturbances (traveling stall cells) in this tip gap region as well as fan performance characteristics including pressure rise and flow rate. The casing plasma actuation is found to reduce the correlation of the rotating stall cells, thereby extending the stall margin of the fan. Various azimuthal arrangements of the plasma actuator casing treatment is explored, as well as input voltage levels to the actuator to determine optimum conditions. NASA SBIR Contract NNX14CC12C.

  1. Separase prevents genomic instability by controlling replication fork speed

    OpenAIRE

    Cucco, Francesco; Palumbo, Elisa; Camerini, Serena; D’Alessio, Barbara; Quarantotti, Valentina; Casella, Maria Luisa; Rizzo, Ilaria Maria; Cukrov, Dubravka; Delia, Domenico; Russo, Antonella; Crescenzi, Marco; Musio, Antonio

    2017-01-01

    Abstract Proper chromosome segregation is crucial for preserving genomic integrity, and errors in this process cause chromosome mis-segregation, which may contribute to cancer development. Sister chromatid separation is triggered by Separase, an evolutionary conserved protease that cleaves the cohesin complex, allowing the dissolution of sister chromatid cohesion. Here we provide evidence that Separase participates in genomic stability maintenance by controlling replication fork speed. We fou...

  2. The relevance of the dynamic stall effect for transient fault operations of active-stall wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, Clemens; Soerensen, Poul; Jensen, Birgitte Bak

    2005-06-15

    This article describes a methodology to quantify the influence of dynamic stall on transient fault operations of active-stall turbines. The model of the dynamic stall effect is introduced briefly. The behaviour of the dynamic stall model during a transient fault operation is described mathematically, and from this its effect quantified. Two quantities are chosen to describe the influence of the dynamic stall effect: one is active power and the other is time delay. Subsequently a transient fault scenario is simulated with and without the dynamic stall effect and the differences discussed. From this comparison, the conclusion is drawn that the dynamic stall effect has some influence on the post-fault behaviour of the wind turbine, and it is hence suggested that the dynamic stall effect is considered if an active-stall wind turbine is to be modelled realistically. (Author)

  3. Load prediction of stall regulated wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerck, A.; Dahlberg, J.Aa. [Aeronautical Research Inst. of Sweden, Bromma (Sweden); Carlen, I. [Chalmers Univ. of Technology, Goeteborg (Sweden). Div. of Marine Structural Engineering; Ganander, H. [Teknikgruppen AB, Sollentua (Sweden)

    1996-12-01

    Measurements of blade loads on a turbine situated in a small wind farm shows that the highest blade loads occur during operation close to the peak power i.e. when the turbine operates in the stall region. In this study the extensive experimental data base has been utilised to compare loads in selected campaigns with corresponding load predictions. The predictions are based on time domain simulations of the wind turbine structure, performed by the aeroelastic code VIDYN. In the calculations a model were adopted in order to include the effects of dynamic stall. This paper describes the work carried out so far within the project and key results. 5 refs, 10 figs

  4. Dynamic stall and 3D effects

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerck, A.; Thor, S.E. [Aeronautical Research Inst. of Sweden, Bromma (Sweden)

    1996-12-01

    The JOULE II project `Dynamic stall and 3D effects` started in January 1994 and was completed in September 1995. The objective of the project has been to increase the understanding of the three-dimensional and unsteady aerodynamics of stall controlled HAWT`s. The objectives have also been to develop `engineering models` suitable for inclusion into aero-elastic codes. The project included the participation of 13 parties within Europe. This paper describes an overview of the work carried out within the project and key results. 3 refs, 4 figs

  5. Education stalls and subsequent stalls in African fertility: A descriptive overview

    Directory of Open Access Journals (Sweden)

    Anne Goujon

    2015-12-01

    Full Text Available Background: Recent stalls in fertility decline have been observed in a few countries in sub-Saharan Africa, and so far no plausible common reason has been identified in the literature. This paper develops the hypothesis that these fertility stalls could be associated with stalls in the progress of education among the women of the relevant cohorts, possibly resulting partly from the Structural Adjustment Programs (SAPs of the 1980s. Methods: We descriptively link the change in the education composition of successive cohorts of young women in sub-Saharan Africa and the recent fertility stalls. We use reconstructed data on population by age, gender, and level of education from www.wittgenstein centre.org/dataexplorer, and fertility rates from the United Nations. Results: In most sub-Saharan African countries, we observe that the same countries that had fertility stalls had a stall in the progress of education, particularly for young women who were of primary school age during the 1980s, when most of the countries were under structural adjustment. Conversely, stalls in fertility are less common in countries that did not have an education stall, possibly in relation to SAPs. Conclusions: The results point to the possibility of a link between the recent fertility stalls and discontinuities in the improvement of the education of the relevant cohorts, which in turn could be related to the SAPs in the 1980s. This descriptive finding now needs to be corroborated through more detailed cohort-specific fertility analysis. If the education-fertility link can be further established, it will have important implications for the projections of population growth in affected countries.

  6. Calculation of Rotor Performance and Loads Under Stalled Conditions

    National Research Council Canada - National Science Library

    Yeo, Hyeonsoo

    2003-01-01

    Rotor behavior in stalled conditions is investigated using wind tunnel test data of a 1/10-scale CH-47B/C type rotor, which provides a set of test conditions extending from unstalled to light stall...

  7. Loss of Caenorhabditis elegans BRCA1 Promotes Genome Stability During Replication in smc-5 Mutants

    Science.gov (United States)

    Wolters, Stefanie; Ermolaeva, Maria A.; Bickel, Jeremy S.; Fingerhut, Jaclyn M.; Khanikar, Jayshree; Chan, Raymond C.; Schumacher, Björn

    2014-01-01

    DNA damage by ultraviolet (UV) light poses a risk for mutagenesis and a potential hindrance for cell cycle progression. Cells cope with UV-induced DNA damage through two general strategies to repair the damaged nucleotides and to promote cell cycle progression in the presence of UV-damaged DNA. Defining the genetic pathways and understanding how they function together to enable effective tolerance to UV remains an important area of research. The structural maintenance of chromosomes (SMC) proteins form distinct complexes that maintain genome stability during chromosome segregation, homologous recombination, and DNA replication. Using a forward genetic screen, we identified two alleles of smc-5 that exacerbate UV sensitivity in Caenorhabditis elegans. Germ cells of smc-5-defective animals show reduced proliferation, sensitivity to perturbed replication, chromatin bridge formation, and accumulation of RAD-51 foci that indicate the activation of homologous recombination at DNA double-strand breaks. Mutations in the translesion synthesis polymerase polh-1 act synergistically with smc-5 mutations in provoking genome instability after UV-induced DNA damage. In contrast, the DNA damage accumulation and sensitivity of smc-5 mutant strains to replication impediments are suppressed by mutations in the C. elegans BRCA1/BARD1 homologs, brc-1 and brd-1. We propose that SMC-5/6 promotes replication fork stability and facilitates recombination-dependent repair when the BRC-1/BRD-1 complex initiates homologous recombination at stalled replication forks. Our data suggest that BRC-1/BRD-1 can both promote and antagonize genome stability depending on whether homologous recombination is initiated during DNA double-strand break repair or during replication stalling. PMID:24424777

  8. 16 CFR 1505.50 - Stalled motor testing.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Stalled motor testing. 1505.50 Section 1505... USE BY CHILDREN Policies and Interpretations § 1505.50 Stalled motor testing. (a) § 1505.6(e)(4)(ii) requires that a motor-operated toy be tested with the motor stalled if the construction of the toy is such...

  9. Rinne revisited: steel versus aluminum tuning forks.

    Science.gov (United States)

    MacKechnie, Cheryl A; Greenberg, Jesse J; Gerkin, Richard C; McCall, Andrew A; Hirsch, Barry E; Durrant, John D; Raz, Yael

    2013-12-01

    (1) Determine whether tuning fork material (aluminum vs stainless steel) affects Rinne testing in the clinical assessment of conductive hearing loss (CHL). (2) Determine the relative acoustic and mechanical outputs of 512-Hz tuning forks made of aluminum and stainless steel. Prospective, observational. Outpatient otology clinic. Fifty subjects presenting May 2011 to May 2012 with negative or equivocal Rinne in at least 1 ear and same-day audiometry. Rinne test results using aluminum and steel forks were compared and correlated with the audiometric air-bone gap. Bench top measurements using sound-level meter, microphone, and artificial mastoid. Patients with CHL were more likely to produce a negative Rinne test with a steel fork than with an aluminum fork. Logistic regression revealed that the probability of a negative Rinne reached 50% at a 19 dB air-bone gap for stainless steel versus 27 dB with aluminum. Bench top testing revealed that steel forks demonstrate, in effect, more comparable air and bone conduction efficiencies while aluminum forks have relatively lower bone conduction efficiency. We have found that steel tuning forks can detect a lesser air-bone gap compared to aluminum tuning forks. This is substantiated by observations of clear differences in the relative acoustic versus mechanical outputs of steel and aluminum forks, reflecting underlying inevitable differences in acoustic versus mechanical impedances of these devices, and thus efficiency of coupling sound/vibratory energy to the auditory system. These findings have clinical implications for using tuning forks to determine candidacy for stapes surgery.

  10. Simulation model of an active stall wind turbine controller

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, C.; Hansen, A.D.; Soerensen, P. [Risoe National Lab., Wind Energy Dept., Rosilde (Denmark); Blaabjerg, F. [Aalborg Univ., Inst. of Energy Technology (Denmark)

    2004-07-01

    This paper describes an active stall wind turbine controller. The objective is to develop a general model of an active stall controller in order to simulate the operation of grid connected active stall wind turbines. The active stall turbine concept and its control strategies are presented and evaluated on the basis of simulations. The presented controller is described for continuous operation under all wind speeds from start-up wind speed to shut doven wind speed. Due to its parametric implementation it is general i.e. it can represent different active stall wind turbine controllers and can be implemented in different simulation tools. (au)

  11. Identification of phlebovirus and arenavirus RNA sequences that stall and repress the exoribonuclease XRN1.

    Science.gov (United States)

    Charley, Phillida A; Wilusz, Carol J; Wilusz, Jeffrey

    2018-01-05

    Regulated mRNA decay plays a vital role in determining both the level and quality of cellular gene expression. Viral RNAs must successfully evade this host RNA decay machinery to establish a productive infection. One way for RNA viruses to accomplish this is to target the cellular exoribonuclease XRN1, because this enzyme is accessible in the cytoplasm and plays a major role in mRNA decay. Members of the Flaviviridae use RNA structures in their 5'- or 3'-untranslated regions to stall and repress XRN1, effectively stabilizing viral RNAs while also causing significant dysregulation of host cell mRNA stability. Here, we use a series of biochemical assays to demonstrate that the 3'-terminal portion of the nucleocapsid (N) mRNA of Rift Valley fever virus, a phlebovirus of the Bunyaviridae family, also can effectively stall and repress XRN1. The region responsible for impeding XRN1 includes a G-rich portion that likely forms a G-quadruplex structure. The 3'-terminal portions of ambisense-derived transcripts of multiple arenaviruses also stalled XRN1. Therefore, we conclude that RNAs from two additional families of mammalian RNA viruses stall and repress XRN1. This observation. emphasizes the importance and commonality of this viral strategy to interfere with the 5'-to-3'-exoribonuclease component of the cytoplasmic RNA decay machinery. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Tunisia: high fertility stalls development.

    Science.gov (United States)

    Barberis, M

    1985-01-01

    Despite government policy enacted in 1964 to reduce fertility in order to hasten socioeconomic progress, population pressures continue to impair development in Tunisia. The birth rate fell 20% over the last 2 decades, but this accomplishment has been outweighed by a 50% decline in mortality rates. As a result, the rate of natural population increase has remained relatively constant at 2.5%/year. The initial decline in fertility that followed introduction of the national family planning program appears to have reached a plateau, explained in part by the resurgence of conservatism and religious fundamentalism and the consequent emphasis on women's childbearing roles. Unemployment in rural areas has led to widespread migration and unemployment is as high as 20% in the nonagricultural sector. Many young Tunisians lack adequate educational preparation to enter the labor force; in 1982, 27% of new job entrants could not read or write. The government's plan to decentralize development to stabilize population and achieve equilibrium between regions has been thwarted by the pace of population growth and limited resources. The rural regions where population is increasing the fastest are also the most difficult to reach with family planning programs. On the other hand, there have been some successes in this area when services have been adapted to the lifestyle and traditions of those in these isolated rural villages.

  13. Numerical Investigations of Dynamic Stall Control

    Directory of Open Access Journals (Sweden)

    Florin FRUNZULICA

    2014-04-01

    Full Text Available In this paper we investigated numerically the dynamic stall phenomenon and the possibilities to control it, with application to vertical axis wind turbines (for urban users. The Phenomenon appear at low tip speed ratio (TSR<4 and it has a great impact on structural integrity of the wind turbine and power performances. For this reason we performed a computational study of dynamic stall around NACA 0012 airfoil in pitching motion at relative low Reynolds number (105. Also, we performed the same analysis for four flow control methods: two passive (Gurney flap and slot and two active (blowing jet on the rounded trailing edge and synthetic jet periodically activated. The Results are compared to those of an existing experimental case test.

  14. Dynamic Stall Control Using Plasma Actuators

    Science.gov (United States)

    Webb, Nathan; Singhal, Achal; Castaneda, David; Samimy, Mo

    2017-11-01

    Dynamic stall occurs in many applications, including sharp maneuvers of fixed wing aircraft, wind turbines, and rotorcraft and produces large unsteady aerodynamic loads that can lead to flutter and mechanical failure. This work uses flow control to reduce the unsteady loads by excitation of instabilities in the shear layer over the separated region using nanosecond pulse driven dielectric barrier discharge (NS-DBD) plasma actuators. These actuators have been shown to effectively delay or mitigate static stall. A wide range of flow parameters were explored in the current work: Reynolds number (Re = 167,000 to 500,000), reduced frequency (k = 0.025 to 0.075), and excitation Strouhal number (Ste = 0 to 10). Based on the results, three major conclusions were drawn: (a) Low Strouhal number excitation (Ste eliminated the dynamic stall vortex (DSV), thereby dramatically reducing the unsteady loading. The decrease in the strength of the DSV is achieved by the formation of shear layer coherent structures that bleed the leading-edge vorticity prior to the ejection of the DSV.

  15. Separase prevents genomic instability by controlling replication fork speed.

    Science.gov (United States)

    Cucco, Francesco; Palumbo, Elisa; Camerini, Serena; D'Alessio, Barbara; Quarantotti, Valentina; Casella, Maria Luisa; Rizzo, Ilaria Maria; Cukrov, Dubravka; Delia, Domenico; Russo, Antonella; Crescenzi, Marco; Musio, Antonio

    2018-01-09

    Proper chromosome segregation is crucial for preserving genomic integrity, and errors in this process cause chromosome mis-segregation, which may contribute to cancer development. Sister chromatid separation is triggered by Separase, an evolutionary conserved protease that cleaves the cohesin complex, allowing the dissolution of sister chromatid cohesion. Here we provide evidence that Separase participates in genomic stability maintenance by controlling replication fork speed. We found that Separase interacted with the replication licensing factors MCM2-7, and genome-wide data showed that Separase co-localized with MCM complex and cohesin. Unexpectedly, the depletion of Separase increased the fork velocity about 1.5-fold and caused a strong acetylation of cohesin's SMC3 subunit and altered checkpoint response. Notably, Separase silencing triggered genomic instability in both HeLa and human primary fibroblast cells. Our results show a novel mechanism for fork progression mediated by Separase and thus the basis for genomic instability associated with tumorigenesis. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  16. Mechanically stable tuning fork sensor with high quality factor for the atomic force microscope.

    Science.gov (United States)

    Kim, Kwangyoon; Park, Jun-Young; Kim, K B; Lee, Naesung; Seo, Yongho

    2014-01-01

    A quartz tuning fork was used instead of cantilever as a force sensor for the atomic force microscope. A tungsten tip was made by electrochemical etching from a wire of 50 µm diameter. In order to have mechanical stability of the tuning fork, it was attached on an alumina plate. The tungsten tip was attached on the inside end of a prong of a tuning fork. The phase shift was used as a feedback signal to control the distance between the tip and sample, and the amplitude was kept constant using a lock-in amplifier and a homemade automatic gain controller. Due to the mechanical stability, the sensor shows a high quality factor (∼10(3)), and the image quality obtained with this sensor was equivalent to that of the cantilever-based AFM. © 2014 Wiley Periodicals, Inc.

  17. South Fork Holston River basin 1988 biomonitoring

    Energy Technology Data Exchange (ETDEWEB)

    Saylor, C.F.; Ahlstedt, S.A.

    1990-06-01

    There is concern over the effects of shifts in land use use practices on the aquatic fauna of streams in the South Fork Holston River basin in northwestern North Carolina and southwestern Virginia. Trout reproduction has noticeably declined in the Watauga River subbasin. The Watauga River and Elk River subbasins have been subjected to commercial and resort development. The Middle fork Holston River and the upper South Fork Holston River subbasins have been affected by agricultural and mining activities, respectively (Cox, 1986). To aid reclamation and management of the South Fork Holston basin, Tennessee Valley Authority (TVA) biologists conducted biomonitoring--including index of biotic integrity and macroinvertebrate sampling--on the Middle Fork Holston, South Fork Holston, Watauga, and Elk Rivers to assess cumulative impairment related to changes in habitat and pollutant loading in these subbasins. Biomonitoring can detect environmental degradation, help document problem areas, and assist in development of strategies for managing water quality. This report discusses the methods and materials and results of the biomonitoring of South Fork Holston River Basin. 13 refs., 5 figs., 12 tabs.

  18. Henrys Fork near Ashton, ID (YHEN)

    Data.gov (United States)

    Department of the Interior — Henrys Fork near Ashton, Idaho (YHEN) Sample Collection: Samples were collected near the USGS stream gage 13046000 (Latitude 44°04'11", Longitude 111°30'38" NAD83)....

  19. 14 CFR 23.201 - Wings level stall.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Wings level stall. 23.201 Section 23.201 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS.... Starting from a speed at least 10 knots above the stall speed, the elevator control must be pulled back so...

  20. 14 CFR 33.65 - Surge and stall characteristics.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Surge and stall characteristics. 33.65 Section 33.65 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... stall characteristics. When the engine is operated in accordance with operating instructions required by...

  1. Compressible dynamic stall vorticity flux control using a dynamic ...

    Indian Academy of Sciences (India)

    management of its unsteady vorticity using a variable droop leading edge (VDLE) airfoil. Through ... the pressure gradient term for the dynamic stall conditions encountered by a helicopter-rotor retreating blade. Thus ... This paper discusses control of compressible dynamic stall using the novel idea of variable droop leading ...

  2. Theoretical analysis of transcription process with polymerase stalling

    Science.gov (United States)

    Li, Jingwei; Zhang, Yunxin

    2015-05-01

    Experimental evidence shows that in gene transcription RNA polymerase has the possibility to be stalled at a certain position of the transcription template. This may be due to the template damage or protein barriers. Once stalled, polymerase may backtrack along the template to the previous nucleotide to wait for the repair of the damaged site, simply bypass the barrier or damaged site and consequently synthesize an incorrect messenger RNA, or degrade and detach from the template. Thus, the effective transcription rate (the rate to synthesize correct product mRNA) and the transcription effectiveness (the ratio of the effective transcription rate to the effective transcription initiation rate) are both influenced by polymerase stalling events. So far, no theoretical model has been given to discuss the gene transcription process including polymerase stalling. In this study, based on the totally asymmetric simple exclusion process, the transcription process including polymerase stalling is analyzed theoretically. The dependence of the effective transcription rate, effective transcription initiation rate, and transcription effectiveness on the transcription initiation rate, termination rate, as well as the backtracking rate, bypass rate, and detachment (degradation) rate when stalling, are discussed in detail. The results showed that backtracking restart after polymerase stalling is an ideal mechanism to increase both the effective transcription rate and the transcription effectiveness. Without backtracking, detachment of stalled polymerase can also help to increase the effective transcription rate and transcription effectiveness. Generally, the increase of the bypass rate of the stalled polymerase will lead to the decrease of the effective transcription rate and transcription effectiveness. However, when both detachment rate and backtracking rate of the stalled polymerase vanish, the effective transcription rate may also be increased by the bypass mechanism.

  3. Dynamic Stall in Pitching Airfoils: Aerodynamic Damping and Compressibility Effects

    Science.gov (United States)

    Corke, Thomas C.; Thomas, Flint O.

    2015-01-01

    Dynamic stall is an incredibly rich fluid dynamics problem that manifests itself on an airfoil during rapid, transient motion in which the angle of incidence surpasses the static stall limit. It is an important element of many manmade and natural flyers, including helicopters and supermaneuverable aircraft, and low-Reynolds number flapping-wing birds and insects. The fluid dynamic attributes that accompany dynamic stall include an eruption of vorticity that organizes into a well-defined dynamic stall vortex and massive excursions in aerodynamic loads that can couple with the airfoil structural dynamics. The dynamic stall process is highly sensitive to surface roughness that can influence turbulent transition and to local compressibility effects that occur at free-stream Mach numbers that are otherwise incompressible. Under some conditions, dynamic stall can result in negative aerodynamic damping that leads to limit-cycle growth of structural vibrations and rapid mechanical failure. The mechanisms leading to negative damping have been a principal interest of recent experiments and analysis. Computational fluid dynamic simulations and low-order models have not been good predictors so far. Large-eddy simulation could be a viable approach although it remains computationally intensive. The topic is technologically important owing to the desire to develop next-generation rotorcraft that employ adaptive rotor dynamic stall control.

  4. DNA fork displacement rates in human cells

    International Nuclear Information System (INIS)

    Kapp, L.N.; Painter, R.B.

    1981-01-01

    DNA fork displacement rates were measured in 20 human cell lines by a bromodeoxyuridine-313 nm photolysis technique. Cell lines included representatives of normal diploid, Fanconi's anemia, ataxia telangiectasia, xeroderma pigmentosum, trisomy-21 and several transformed lines. The average value for all the cell lines was 0.53 +- 0.08 μm/min. The average value for individual cell lines, however, displayed a 30% variation. Less than 10% of variation in the fork displacement rate appears to be due to the experimental technique; the remainder is probably due to true variation among the cell types and to culture conditions. (Auth.)

  5. Development of the Pintle Release Fork Mechanism

    International Nuclear Information System (INIS)

    BOGER, R.M.; DALE, R.

    1999-01-01

    An improved method of attachment of the pintle to the piston in the universal sampler is being developed. The mechanism utilizes a forked release disk which captures two balls in a cavity formed by a hole in the piston and a groove in the pintle rod

  6. Flap motion of helicopter rotors with novel, dynamic stall model

    Directory of Open Access Journals (Sweden)

    Han Wei

    2016-01-01

    Full Text Available In this paper, a nonlinear flapping equation for large inflow angles and flap angles is established by analyzing the aerodynamics of helicopter blade elements. In order to obtain a generalized flap equation, the Snel stall model was first applied to determine the lift coefficient of the helicopter rotor. A simulation experiment for specific airfoils was then conducted to verify the effectiveness of the Snel stall model as it applies to helicopters. Results show that the model requires no extraneous parameters compared to the traditional stall model and is highly accurate and practically applicable. Based on the model, the relationship between the flapping angle and the angle of attack was analyzed, as well as the advance ratio under the dynamic stall state.

  7. HAWT dynamic stall response asymmetries under yawed flow conditions

    Energy Technology Data Exchange (ETDEWEB)

    Schreck, S.; Robinson, M.; Hand, M.; Simms, D.

    2000-02-28

    Horizontal axis wind turbines can experience significant time varying aerodynamic loads, potentially causing adverse effects on structures, mechanical components, and power production. As designers attempt lighter and more flexible wind energy machines, greater accuracy and robustness will become even more critical in future aerodynamics models. Aerodynamics modeling advances, in turn, will rely on more thorough comprehension of the three-dimensional, unsteady, vortical flows that dominate wind turbine blade aerodynamics under high load conditions. To experimentally characterize these flows, turbine blade surface pressures were acquired at multiple span locations via the NREL Phase IV Unsteady Aerodynamics Experiment. Surface pressures and associated normal force histories were used to characterize dynamic stall vortex kinematics and normal force amplification. Dynamic stall vortices and normal force amplification were confirmed to occur in response to angle of attack excursions above the static stall threshold. Stall vortices occupied approximately one-half of the blade span and persisted for nearly one-fourth of the blade rotation cycle. Stall vortex convection varied along the blade, resulting in dramatic deformation of the vortex. Presence and deformation of the dynamic stall vortex produced corresponding amplification of normal forces. Analyses revealed consistent alterations to vortex kinematics in response to changes in reduced frequency, span location, and yaw error. Finally, vortex structures and kinematics not previously documented for wind turbine blades were isolated.

  8. RECQ5 Helicase Cooperates with MUS81 Endonuclease in Processing Stalled Replication Forks at Common Fragile Sites during Mitosis

    DEFF Research Database (Denmark)

    Di Marco, Stefano; Hasanova, Zdenka; Kanagaraj, Radhakrishnan

    2017-01-01

    The MUS81-EME1 endonuclease cleaves late replication intermediates at common fragile sites (CFSs) during early mitosis to trigger DNA-repair synthesis that ensures faithful chromosome segregation. Here, we show that these DNA transactions are promoted by RECQ5 DNA helicase in a manner dependent...

  9. Is Social Licence A Licence To Stall?

    Directory of Open Access Journals (Sweden)

    Mark Lowey

    2016-03-01

    Full Text Available The School of Public Policy at the University of Calgary organized a one-day symposium on Oct. 8, 2014 in Calgary, as part of the School’s TransCanada Corporation Energy Policy and Regulatory Frameworks Program. The symposium was titled “Is Social License a License to Stall?” Held at the Hotel Arts, the event attracted a full-capacity audience of about 110 people, including representatives from industry, government and environmental non-government organizations. The symposium included four moderated panel sessions and a keynote speaker at lunch. The School of Public Policy set the framework for discussion at the Calgary symposium with the following description: Canada’s regulators act in the public interest to review energy and infrastructure project applications. Regulators are guided by procedural fairness and follow a transparent application, review and hearing process with data filings and sworn testimony. But that’s changing. “Social license” is a relatively new term, which some interests are using to create a different standard for the approval of projects — especially energy projects. According to social license advocates, projects must meet often ill-defined requirements set up by non-governmental organizations, local residents or other interests — a new hurdle for project approval, but without the rigour and rule of law of a regulator. Is social license a meaningful addition to the regulatory process, or is it being used as a constantly moving goal-post designed to slow down regulatory processes, delay project implementation, frustrate energy infrastructure expansion and even enrich those advocates who promote it as a new model? This paper summarises the discussion and the themes that emerged throughout the day. Most notably, panellists concluded that “social licence” is a real and significant issue that presents both an opportunity and a problem, not only for regulators but for all parties involved in the

  10. Code Forking, Governance, and Sustainability in Open Source Software

    Directory of Open Access Journals (Sweden)

    Juho Lindman

    2013-01-01

    Full Text Available The right to fork open source code is at the core of open source licensing. All open source licenses grant the right to fork their code, that is to start a new development effort using an existing code as its base. Thus, code forking represents the single greatest tool available for guaranteeing sustainability in open source software. In addition to bolstering program sustainability, code forking directly affects the governance of open source initiatives. Forking, and even the mere possibility of forking code, affects the governance and sustainability of open source initiatives on three distinct levels: software, community, and ecosystem. On the software level, the right to fork makes planned obsolescence, versioning, vendor lock-in, end-of-support issues, and similar initiatives all but impossible to implement. On the community level, forking impacts both sustainability and governance through the power it grants the community to safeguard against unfavourable actions by corporations or project leaders. On the business-ecosystem level forking can serve as a catalyst for innovation while simultaneously promoting better quality software through natural selection. Thus, forking helps keep open source initiatives relevant and presents opportunities for the development and commercialization of current and abandoned programs.

  11. Dynamic Stall Characteristics of Drooped Leading Edge Airfoils

    Science.gov (United States)

    Sankar, Lakshmi N.; Sahin, Mehmet; Gopal, Naveen

    2000-01-01

    Helicopters in high-speed forward flight usually experience large regions of dynamic stall over the retreating side of the rotor disk. The rapid variations in the lift and pitching moments associated with the stall process can result in vibratory loads, and can cause fatigue and failure of pitch links. In some instances, the large time lag between the aerodynamic forces and the blade motion can trigger stall flutter. A number of techniques for the alleviation of dynamic stall have been proposed and studied by researchers. Passive and active control techniques have both been explored. Passive techniques include the use of high solidity rotors that reduce the lift coefficients of individual blades, leading edge slots and leading edge slats. Active control techniques include steady and unsteady blowing, and dynamically deformable leading edge (DDLE) airfoils. Considerable amount of experimental and numerical data has been collected on the effectiveness of these concepts. One concept that has not received as much attention is the drooped-leading edge airfoil idea. It has been observed in wind tunnel studies and flight tests that drooped leading edge airfoils can have a milder dynamic stall, with a significantly milder load hysteresis. Drooped leading edge airfoils may not, however, be suitable at other conditions, e.g. in hover, or in transonic flow. Work needs to be done on the analysis and design of drooped leading edge airfoils for efficient operation in a variety of flight regimes (hover, dynamic stall, and transonic flow). One concept that is worthy of investigation is the dynamically drooping airfoil, where the leading edge shape is changed roughly once-per-rev to mitigate the dynamic stall.

  12. Dynamics and Control of Three-Dimensional Perching Maneuver under Dynamic Stall Influence

    Science.gov (United States)

    Feroskhan, Mir Alikhan Bin Mohammad

    initial altitude range. Contraction analysis is shown to be a useful technique in identifying the state variables that are required to be tracked for attaining stability of optimal perching trajectories. Based on the selected tracking variables, two sliding control strategies are proposed and comparatively examined to close the control loop and provide the required robustness and convergence to the optimal perching trajectory in the presence of perturbations and dynamic stall model inaccuracies. This dissertation concludes that the sliding controller with the adaptive gain feature is more effective and essential in providing better tracking performance through illustrations of the corresponding convergence area and at higher intensity of perturbations.

  13. The forked flap repair for hypospadias

    Directory of Open Access Journals (Sweden)

    Anil Chadha

    2012-01-01

    Full Text Available Context: Despite the abundance of techniques for the repair of Hypospadias, its problems still persist and a satisfactory design to correct the penile curvature with the formation of neourethra from the native urethral tissue or genital or extragenital tissues, with minimal postoperative complications has yet to evolve. Aim: Persisting with such an endeavor, a new technique for the repair of distal and midpenile hypospadias is described. Materials and Methods: The study has been done in 70 cases over the past 11 years. The "Forked-Flap" repair is a single stage method for the repair of such Hypospadias with chordee. It takes advantage of the rich vascular communication at the corona and capitalizes on the established reliability of the meatal based flip-flap. The repair achieves straightening of the curvature of the penis by complete excision of chordee tissue from the ventral surface of the penis beneath the urethral plate. The urethra is reconstructed using the native plate with forked flap extensions and genital tissue relying on the concept of meatal based flaps. Water proofing by dartos tissue and reinforcement by Nesbit′s prepucial tissue transfer completes the one stage procedure. Statistical Analysis: An analysis of 70 cases of this single stage technique of repair of penile hypospadias with chordee, operated at 3 to 5 years of age over the past 11 years is presented. Results and Conclusion: The Forked Flap gives comparable and replicable results; except for a urethrocutaneous fistula rate of 4% no other complications were observed.

  14. The Dynamics of SecM-Induced Translational Stalling

    Directory of Open Access Journals (Sweden)

    Albert Tsai

    2014-06-01

    Full Text Available SecM is an E. coli secretion monitor capable of stalling translation on the prokaryotic ribosome without cofactors. Biochemical and structural studies have demonstrated that the SecM nascent chain interacts with the 50S subunit exit tunnel to inhibit peptide bond formation. However, the timescales and pathways of stalling on an mRNA remain undefined. To provide a dynamic mechanism for stalling, we directly tracked the dynamics of elongation on ribosomes translating the SecM stall sequence (FSTPVWISQAQGIRAGP using single-molecule fluorescence techniques. Within 1 min, three peptide-ribosome interactions work cooperatively over the last five codons of the SecM sequence, leading to severely impaired elongation rates beginning from the terminal proline and lasting four codons. Our results suggest that stalling is tightly linked to the dynamics of elongation and underscore the roles that the exit tunnel and nascent chain play in controlling fundamental steps in translation.

  15. The dynamics of SecM-induced translational stalling.

    Science.gov (United States)

    Tsai, Albert; Kornberg, Guy; Johansson, Magnus; Chen, Jin; Puglisi, Joseph D

    2014-06-12

    SecM is an E. coli secretion monitor capable of stalling translation on the prokaryotic ribosome without cofactors. Biochemical and structural studies have demonstrated that the SecM nascent chain interacts with the 50S subunit exit tunnel to inhibit peptide bond formation. However, the timescales and pathways of stalling on an mRNA remain undefined. To provide a dynamic mechanism for stalling, we directly tracked the dynamics of elongation on ribosomes translating the SecM stall sequence (FSTPVWISQAQGIRAGP) using single-molecule fluorescence techniques. Within 1 min, three peptide-ribosome interactions work cooperatively over the last five codons of the SecM sequence, leading to severely impaired elongation rates beginning from the terminal proline and lasting four codons. Our results suggest that stalling is tightly linked to the dynamics of elongation and underscore the roles that the exit tunnel and nascent chain play in controlling fundamental steps in translation. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  16. A Comparative Study of Three Methodologies for Modeling Dynamic Stall

    Science.gov (United States)

    Sankar, L.; Rhee, M.; Tung, C.; ZibiBailly, J.; LeBalleur, J. C.; Blaise, D.; Rouzaud, O.

    2002-01-01

    During the past two decades, there has been an increased reliance on the use of computational fluid dynamics methods for modeling rotors in high speed forward flight. Computational methods are being developed for modeling the shock induced loads on the advancing side, first-principles based modeling of the trailing wake evolution, and for retreating blade stall. The retreating blade dynamic stall problem has received particular attention, because the large variations in lift and pitching moments encountered in dynamic stall can lead to blade vibrations and pitch link fatigue. Restricting to aerodynamics, the numerical prediction of dynamic stall is still a complex and challenging CFD problem, that, even in two dimensions at low speed, gathers the major difficulties of aerodynamics, such as the grid resolution requirements for the viscous phenomena at leading-edge bubbles or in mixing-layers, the bias of the numerical viscosity, and the major difficulties of the physical modeling, such as the turbulence models, the transition models, whose both determinant influences, already present in static maximal-lift or stall computations, are emphasized by the dynamic aspect of the phenomena.

  17. Human ribonuclease H1 resolves R-loops and thereby enables progression of the DNA replication fork.

    Science.gov (United States)

    Parajuli, Shankar; Teasley, Daniel C; Murali, Bhavna; Jackson, Jessica; Vindigni, Alessandro; Stewart, Sheila A

    2017-09-15

    Faithful DNA replication is essential for genome stability. To ensure accurate replication, numerous complex and redundant replication and repair mechanisms function in tandem with the core replication proteins to ensure DNA replication continues even when replication challenges are present that could impede progression of the replication fork. A unique topological challenge to the replication machinery is posed by RNA-DNA hybrids, commonly referred to as R-loops. Although R-loops play important roles in gene expression and recombination at immunoglobulin sites, their persistence is thought to interfere with DNA replication by slowing or impeding replication fork progression. Therefore, it is of interest to identify DNA-associated enzymes that help resolve replication-impeding R-loops. Here, using DNA fiber analysis, we demonstrate that human ribonuclease H1 (RNH1) plays an important role in replication fork movement in the mammalian nucleus by resolving R-loops. We found that RNH1 depletion results in accumulation of RNA-DNA hybrids, slowing of replication forks, and increased DNA damage. Our data uncovered a role for RNH1 in global DNA replication in the mammalian nucleus. Because accumulation of RNA-DNA hybrids is linked to various human cancers and neurodegenerative disorders, our study raises the possibility that replication fork progression might be impeded, adding to increased genomic instability and contributing to disease. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Time Accurate Unsteady Simulation of the Stall Inception Process in the Compression System of a US Army Helicopter Gas Turbine Engine

    National Research Council Canada - National Science Library

    Hathaway, Michael D; Herrick, Greg; Chen, Jenping; Webster, Robert

    2004-01-01

    .... Improved understanding of the stall inception process and how stall control technologies mitigate such will provide compressors with increased tolerance to stall, thereby expanding the operational...

  19. Needs assessment for the Greenway Grand Forks-East Grand Forks development and public education

    Science.gov (United States)

    Munski, Laura

    Following the flood of 1997, the U.S. Army Corps of Engineers included the Greenway Grand Forks---East Grand Forks (the Greenway) as a flood control measure for Grand Forks, North Dakota and East Grand Forks, Minnesota. It extends along both the Red River of the North and the Red Lake River, encompassing 2200 acres of land. The cities of Grand Forks and East Grand Forks hired consultants to assist with the postflood planning process. The planning process culminated with the Red River of the North Greenway Final Report (Flink, 1998). The purpose of this study was to determine if the development of the Greenway addressed the objectives of the planning report. The history of the land adjacent to the rivers was reviewed to document the progression of riverfront development. Anecdotal evidence was collected, field observations were made, city council minutes were reviewed, Greenway Technical Committee members were interviewed, Greenway Technical Committee minutes were reviewed, and the Greenway Grand Forks---East Grand Forks survey results were reviewed to determine if the objectives of the Red River of the North Greenway Final Report were addressed. A cross section survey was designed by Laura Munski for this dissertation research. The survey was approved by the Greenway Technical Committee. The survey collected both quantitative and qualitative data from the community. The purpose of the survey portion of the research project was to ascertain how residents were kept informed of activities on the Greenway and what amenities residents were using on the Greenway and to solicit their comments regarding the Greenway. The results of the survey research were used in both marketing and event planning for the Greenway. The singular qualitative survey question gave respondents an opportunity to share their comments regarding the Greenway. The qualitative data analysis provided insight to the amenities and educational programs desired by respondents, their concerns regarding the

  20. Active Suppression of Rotating Stall Inception with Distributed Jet Actuation

    Directory of Open Access Journals (Sweden)

    Huu Duc Vo

    2007-01-01

    Full Text Available An analytical and experimental investigation of the effectiveness of full-span distributed jet actuation for active suppression of long length-scale rotating stall inception is carried out. Detailed modeling and experimental verification highlight the important effects of mass addition, discrete injectors, and feedback dynamics, which may be overlooked in preliminary theoretical studies of active control with jet injection. A model of the compression system incorporating nonideal injection and feedback dynamics is verified with forced response measurements to predict the right trends in the movement of the critical pole associated with the stall precursor. Active control experiments with proportional feedback control show that the predicted stall precursors are suppressed to give a 5.5% range extension in compressor flow coefficient. In addition, results suggest that the proposed model could be used to design a more sophisticated controller to further improve performance while reducing actuator bandwidth requirements.

  1. Stall Recovery Guidance Algorithms Based on Constrained Control Approaches

    Science.gov (United States)

    Stepanyan, Vahram; Krishnakumar, Kalmanje; Kaneshige, John; Acosta, Diana

    2016-01-01

    Aircraft loss-of-control, in particular approach to stall or fully developed stall, is a major factor contributing to aircraft safety risks, which emphasizes the need to develop algorithms that are capable of assisting the pilots to identify the problem and providing guidance to recover the aircraft. In this paper we present several stall recovery guidance algorithms, which are implemented in the background without interfering with flight control system and altering the pilot's actions. They are using input and state constrained control methods to generate guidance signals, which are provided to the pilot in the form of visual cues. It is the pilot's decision to follow these signals. The algorithms are validated in the pilot-in-the loop medium fidelity simulation experiment.

  2. Exploratory study of the effects of wing-leading-edge modifications on the stall/spin behavior of a light general aviation airplane

    Science.gov (United States)

    1979-01-01

    Configurations with full-span and segmented leading-edge flaps and full-span and segmented leading-edge droop were tested. Studies were conducted with wind-tunnel models, with an outdoor radio-controlled model, and with a full-scale airplane. Results show that wing-leading-edge modifications can produce large effects on stall/spin characteristics, particularly on spin resistance. One outboard wing-leading-edge modification tested significantly improved lateral stability at stall, spin resistance, and developed spin characteristics.

  3. EQUINE THERMOREGULATORY RESPONSES DURING SUMMERTIME ROAD TRANSPORT AND STALL CONFINEMENT

    Directory of Open Access Journals (Sweden)

    ANGELA R. GREEN

    2007-04-01

    Full Text Available Thermoregulatory responses of horses subjected to summer-time road transport and stall confinement were investigated in this study. Six mature geldings were transported 168 km in a 4-horse trailer and were monitored while tethered in their stalls, on alternate days. Core body temperature (GT demonstrated negligible response during transport, but GT following transport was higher than GT for non-transport. GT tended to increase with increased temperature humidity index (THI. THI within the trailer was greatest for positions near the front, and was influenced by daily weather which varied over experiment days from heat stress conditions to moderate discomfort.

  4. A dynamic stall model for airfoils with deformable trailing edges

    DEFF Research Database (Denmark)

    Andersen, Peter Bjørn; Gaunaa, Mac; Bak, Christian

    2009-01-01

    The present work contains an extension of the Beddoes-Leishman-type dynamic stall model. In this work, a deformable trailing-edge flap has been added to the dynamic stall model. The model predicts the unsteady aerodynamic forces and moments on an airfoil section undergoing arbitrary motion in hea...... for the attached flow region and Hansen et al. The model is compared qualitatively to wind tunnel measurements of a Riso/ B1-18 blade section equipped with deformable trailing-edge flap devices in the form of piezoelectric devices. Copyright © 2009 John Wiley & Sons, Ltd....

  5. Regulation of bacterial gene expression by ribosome stalling and rescuing.

    Science.gov (United States)

    Jin, Yongxin; Jin, Shouguang; Wu, Weihui

    2016-05-01

    Ribosome is responsible for protein synthesis and is able to monitor the sequence and structure of the nascent peptide. Such ability plays an important role in determining overall gene expression profile of the bacteria through ribosome stalling and rescuing. In this review, we briefly summarize our current understanding of the regulation of gene expression through ribosome stalling and rescuing in bacteria, as well as mechanisms that modulate ribosome activity. Understanding the mechanisms of how bacteria modulate ribosome activity will provide not only fundamental insights into bacterial gene regulation, but also new candidate targets for the development of novel antimicrobial agents.

  6. A dynamic stall model for airfoils with deformable trailing edges

    DEFF Research Database (Denmark)

    Andersen, Peter Bjørn; Gaunaa, Mac; Bak, Dan Christian

    2007-01-01

    on an airfoil section undergoing arbitrary motion in heave, lead-lag, pitch, Trailing Edge (TE) flapping. In the linear region, the model reduces to the inviscid model of Gaunaa [4], which includes the aerodynamic effect of a thin airfoil with a deformable camberline in inviscid flow. Therefore, the proposed......The present work contains an extension of the Beddoes-Leishman (B-L) type dynamic stall model, as described by Hansen et al. [7]. In this work a Deformable Trailing Edge Geometry (DTEG) has been added to the dynamic stall model. The model predicts the unsteady aerodynamic forces and moments...

  7. Measurement of viscosity in small volumes of fluids by tuning fork oscillators

    Directory of Open Access Journals (Sweden)

    Rotter Miloš

    2012-04-01

    Full Text Available We report on the construction and performance of a home-built viscometer employing a quartz tuning fork resonator as the sensing element. The resulting device allows measuring the viscosity of fluids in volumes as low as 300 μl, while controlling the temperature between -120 °C and 150 °C. For non-conducting fluids, bare tuning forks can be used, reaching the accuracy of 1% or better in the whole temperature range. For weakly conducting fluids such as aqueous solutions, an insulating coating of paint is applied, resulting in reduced sensitivity and accuracy. The capabilities and limitations of the viscometer are illustrated on the viscosity measurements of n-hexane (between -90 °C and +50 °C and water (between 10 °C and 90 °C. Improvements regarding performance in conducting liquids and temperature stabilization are discussed.

  8. Dynamic Stall Flow Control Through the Use of a Novel Plasma Based Actuator Technology, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Lynntech proposes a novel flow control methodology for airfoils undergoing dynamic stall. Dynamic stall refers to an aerodynamic phenomenon that is experienced by...

  9. Unsteady Double Wake Model for the Simulation of Stalled Airfoils

    DEFF Research Database (Denmark)

    Ramos García, Néstor; Cayron, Antoine; Sørensen, Jens Nørkær

    2015-01-01

    separation and its dynamics. In this paper, the calculated integral forces have been successfully validated against wind tunnel measurements for the FFA-W3-211 airfoil. Furthermore, the computed highly unsteady flow field is analyzed in detail for a set of angles of attack ranging from light to deep stall...

  10. Dynamic Characteristics of Rotating Stall in Mixed Flow Pump

    Directory of Open Access Journals (Sweden)

    Xiaojun Li

    2013-01-01

    Full Text Available Rotating stall, a phenomenon that causes flow instabilities and pressure hysteresis by propagating at some fraction of the impeller rotational speed, can occur in centrifugal impellers, mixed impellers, radial diffusers, or axial diffusers. Despite considerable efforts devoted to the study of rotating stall in pumps, the mechanics of this phenomenon are not sufficiently understood. The propagation mechanism and onset of rotating stall are not only affected by inlet flow but also by outlet flow as well as the pressure gradient in the flow passage. As such, the complexity of these concepts is not covered by the classical explanation. To bridge this research gap, the current study investigated prerotation generated at the upstream of the impeller, leakage flow at the tip clearance between the casing and the impeller, and strong reserve flow at the inlet of the diffuser. Understanding these areas will clarify the origin of the positive slope of the head-flow performance curve for a mixed flow pump. Nonuniform pressure distribution and adverse pressure gradient were also introduced to evaluate the onset and development of rotating stall within the diffuser.

  11. The Mechanical Impact of Aerodynamic Stall on Tunnel Ventilation Fans

    Directory of Open Access Journals (Sweden)

    A. G. Sheard

    2012-01-01

    Full Text Available This paper describes work aimed at establishing the ability of a tunnel ventilation fan to operate without risk of mechanical failure in the event of aerodynamic stall. The research establishes the aerodynamic characteristics of a typical tunnel ventilation fan when operated in both stable and stalled aerodynamic conditions, with and without an anti-stall stabilisation ring, with and without a “nonstalling” blade angle and at full, half, and one quarter design speed. It also measures the fan’s peak stress, thus facilitating an analysis of the implications of the experimental results for mechanical design methodology. The paper concludes by presenting three different strategies for tunnel ventilation fan selection in applications where the selected fan will most likely stall. The first strategy selects a fan with a low-blade angle that is nonstalling. The second strategy selects a fan with a high-pressure developing capability. The third strategy selects a fan with a fitted stabilisation ring. Tunnel ventilation system designers each have their favoured fan selection strategy. However, all three strategies can produce system designs within which a tunnel ventilation fan performs reliably in-service. The paper considers the advantages and disadvantages of each selection strategy and considered the strengths and weaknesses of each.

  12. A farm to fork approach to nutritious school meals: Tackling ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-04-26

    Apr 26, 2016 ... In St Kitts-Nevis and Trinidad and Tobago, partnerships between the agriculture, health, and education sectors have united in a "Farm to Fork" effort to tackle childhood obesity. The Farm to Fork model is built on three pillars: increased fruit and vegetables in school lunches; procurement from local farmers; ...

  13. THE IMPACT OF LOCALIZATION AND BARN TYPE ON INSOLATION OF SIDEWALL STALLS DURING SUMMER

    Directory of Open Access Journals (Sweden)

    Sabina Angrecka

    2017-07-01

    The obtained results allowed us to identify optimal orientation of barns and to suggest the simplest technical measures to protect sidewall stalls from solar heat gain deleterious to cows. The model analysis of stall shading demonstrated that extension of barn eaves to 1 m on the southern side reduced the insolation of stalls over even up to 90% of their area.

  14. A CFD Database for Airfoils and Wings at Post-Stall Angles of Attack

    Science.gov (United States)

    Petrilli, Justin; Paul, Ryan; Gopalarathnam, Ashok; Frink, Neal T.

    2013-01-01

    This paper presents selected results from an ongoing effort to develop an aerodynamic database from Reynolds-Averaged Navier-Stokes (RANS) computational analysis of airfoils and wings at stall and post-stall angles of attack. The data obtained from this effort will be used for validation and refinement of a low-order post-stall prediction method developed at NCSU, and to fill existing gaps in high angle of attack data in the literature. Such data could have potential applications in post-stall flight dynamics, helicopter aerodynamics and wind turbine aerodynamics. An overview of the NASA TetrUSS CFD package used for the RANS computational approach is presented. Detailed results for three airfoils are presented to compare their stall and post-stall behavior. The results for finite wings at stall and post-stall conditions focus on the effects of taper-ratio and sweep angle, with particular attention to whether the sectional flows can be approximated using two-dimensional flow over a stalled airfoil. While this approximation seems reasonable for unswept wings even at post-stall conditions, significant spanwise flow on stalled swept wings preclude the use of two-dimensional data to model sectional flows on swept wings. Thus, further effort is needed in low-order aerodynamic modeling of swept wings at stalled conditions.

  15. Simulation Model of an Active-stall Fixed-speed Wind Turbine Controller

    DEFF Research Database (Denmark)

    Jauch, Clemens; Hansen, Anca D.; Soerensen, Poul

    2004-01-01

    This paper describes an active-stall wind turbine controller. The objective is to develop a general model of an active stall controller in order to simulate the operation of grid connected active stall wind turbines. The active stall turbine concept and its control strategies are presented...... and evaluated by simulations. The presented controller is described for continuous operation under all wind speeds from start-up wind speed to shut down wind speed. Due to its parametric implementation it is general i.e. it can represent different active stall wind turbine controllers and can be implemented...

  16. Simulation model of an active-stall fixed-speed wind turbine controller

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, C.; Hansen, A.D.; Sorensen, P.; Blaabjerg, F.

    2004-07-01

    This paper describes an active-stall wind turbine controller. The objective is to develop a general model of an active stall controller in order to simulate the operation of grid connected active stall wind turbines. The active stall turbine concept and its control strategies are presented and evaluated by simulations. The presented controller is described for continuous operation under all wind speeds from start-up wind speed to shut down wind speed. Due to its parametric implementation it is general i. e. it can represent different active stall wind turbine controllers and can be implemented in different simulation tools. (author)

  17. Stabilization

    Directory of Open Access Journals (Sweden)

    Muhammad H. Al-Malack

    2016-07-01

    Full Text Available Fuel oil flyash (FFA produced in power and water desalination plants firing crude oils in the Kingdom of Saudi Arabia is being disposed in landfills, which increases the burden on the environment, therefore, FFA utilization must be encouraged. In the current research, the effect of adding FFA on the engineering properties of two indigenous soils, namely sand and marl, was investigated. FFA was added at concentrations of 5%, 10% and 15% to both soils with and without the addition of Portland cement. Mixtures of the stabilized soils were thoroughly evaluated using compaction, California Bearing Ratio (CBR, unconfined compressive strength (USC and durability tests. Results of these tests indicated that stabilized sand mixtures could not attain the ACI strength requirements. However, marl was found to satisfy the ACI strength requirement when only 5% of FFA was added together with 5% of cement. When the FFA was increased to 10% and 15%, the mixture’s strength was found to decrease to values below the ACI requirements. Results of the Toxicity Characteristics Leaching Procedure (TCLP, which was performed on samples that passed the ACI requirements, indicated that FFA must be cautiously used in soil stabilization.

  18. Flow and Noise Characteristics of Centrifugal Fan under Different Stall Conditions

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2014-01-01

    Full Text Available An implicit, time-accurate 3D Reynolds-averaged Navier-Stokes (RANS solver is used to simulate the rotating stall phenomenon in a centrifugal fan. The goal of the present work is to shed light on the flow field and particularly the aerodynamic noise at different stall conditions. Aerodynamic characteristics, frequency domain characteristics, and the contours of sound power level under two different stall conditions are discussed in this paper. The results show that, with the decrease of valve opening, the amplitude of full pressure and flow fluctuations tends to be larger and the stall frequency remains the same. The flow field analysis indicates that the area occupied by stall cells expands with the decrease of flow rate. The noise calculation based on the simulation underlines the role of vortex noise after the occurrence of rotating stall, showing that the high noise area rotates along with the stall cell in the circumferential direction.

  19. DYNSTALL: Subroutine package with a dynamic stall model

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerck, Anders [Aeronautical Research Inst. of Sweden, Bromma (Sweden)

    2001-03-01

    A subroutine package, called DYNSTALL, for the calculation of 2D unsteady airfoil aerodynamics is described. The subroutines are written in FORTRAN. DYNSTALL is basically an implementation of the Beddoes-Leishman dynamic stall model. This model is a semi-empirical model for dynamic stall. It includes, however, also models for attached flow unsteady aerodynamics. It is complete in the sense that it treats attached flow as well as separated flow. Semi-empirical means that the model relies on empirically determined constants. Semi because the constants are constants in equations with some physical interpretation. It requires the input of 2D airfoil aerodynamic data via tables as function of angle of attack. The method is intended for use in an aeroelastic code with the aerodynamics solved by blade/element method. DYNSTALL was written to work for any 2D angles of attack relative to the airfoil, e.g. flow from the rear of an airfoil.

  20. Chemical and biological sensing using tuning forks

    Science.gov (United States)

    Tao, Nongjian; Boussaad, Salah

    2012-07-10

    A device for sensing a chemical analyte is disclosed. The device is comprised of a vibrating structure having first and second surfaces and having an associated resonant frequency and a wire coupled between the first and second surfaces of the vibrating structure, wherein the analyte interacts with the wire and causes a change in the resonant frequency of the vibrating structure. The vibrating structure can include a tuning fork. The vibrating structure can be comprised of quartz. The wire can be comprised of polymer. A plurality of vibrating structures are arranged in an array to increase confidence by promoting a redundancy of measurement or to detect a plurality of chemical analytes. A method of making a device for sensing a chemical analyte is also disclosed.

  1. Fork gratings based on ferroelectric liquid crystals.

    Science.gov (United States)

    Ma, Y; Wei, B Y; Shi, L Y; Srivastava, A K; Chigrinov, V G; Kwok, H-S; Hu, W; Lu, Y Q

    2016-03-21

    In this article, we disclose a fork grating (FG) based on the photo-aligned ferroelectric liquid crystal (FLC). The Digital Micro-mirror Device based system is used as a dynamic photomask to generated different holograms. Because of controlled anchoring energy, the photo alignment process offers optimal conditions for the multi-domain FLC alignment. Two different electro-optical modes namely DIFF/TRANS and DIFF/OFF switchable modes have been proposed where the diffraction can be switched either to no diffraction or to a completely black state, respectively. The FLC FG shows high diffraction efficiency and fast response time of 50µs that is relatively faster than existing technologies. Thus, the FLC FG may pave a good foundation toward optical vertices generation and manipulation that could find applications in a variety of devices.

  2. Fixed-speed active-stall wind turbines in offshore applications

    DEFF Research Database (Denmark)

    Akhmatov, Vladislav; Nielsen, Arne Hejde

    2005-01-01

    A large offshore wind farm in the East Danish power system was commissioned in 2003 at Rodsand. The power capacity of the wind farm is 165 MW divided between 72 wind turbines. For this large offshore application, robust and well-known wind technology has been chosen in the form of fixed-speed, ac......, active-stall wind turbines equipped with induction generators. In this paper, maintaining and improving the short-term voltage stability is discussed and systematized in terms of this wind technology. Copyright (C) 2004 John Wiley Sons, Ltd.......A large offshore wind farm in the East Danish power system was commissioned in 2003 at Rodsand. The power capacity of the wind farm is 165 MW divided between 72 wind turbines. For this large offshore application, robust and well-known wind technology has been chosen in the form of fixed-speed...

  3. Study and Control of a Radial Vaned Diffuser Stall

    Directory of Open Access Journals (Sweden)

    Aurélien Marsan

    2012-01-01

    Full Text Available The aim of the present study is to evaluate the efficiency of a boundary layer suction technique in case of a centrifugal compressor stage in order to extend its stable operating range. First, an analysis of the flow pattern within the radial vaned diffuser is presented. It highlights the stall of the diffuser vanes when reaching a low massflow. A boundary layer separation in the hub-suction side corner grows when decreasing the massflow from the nominal operating point to the surge and finally leads to a massive stall. An aspiration strategy is investigated in order to control the stall. The suction slot is put in the vicinity of the saddle that originates the main separating skin-friction line, identified thanks to the analysis of the skin-friction pattern. Several aspiration massflow rates are tested, and two different modelings of the aspiration are evaluated. Finally, an efficient control is reached with a removal of only 0,1% of the global massflow and leads—from a steady-state calculations point of view—to an increase by 40% of the compressor operating range extent.

  4. Vorticity Transport on a Flexible Wing in Stall Flutter

    Science.gov (United States)

    Akkala, James; Buchholz, James; Farnsworth, John; McLaughlin, Thomas

    2014-11-01

    The circulation budget within dynamic stall vortices was investigated on a flexible NACA 0018 wing model of aspect ratio 6 undergoing stall flutter. The wing had an initial angle of attack of 6 degrees, Reynolds number of 1 . 5 ×105 and large-amplitude, primarily torsional, limit cycle oscillations were observed at a reduced frequency of k = πfc / U = 0 . 1 . Phase-locked stereo PIV measurements were obtained at multiple chordwise planes around the 62.5% and 75% spanwise locations to characterize the flow field within thin volumetric regions over the suction surface. Transient surface pressure measurements were used to estimate boundary vorticity flux. Recent analyses on plunging and rotating wings indicates that the magnitude of the pressure-gradient-driven boundary flux of secondary vorticity is a significant fraction of the magnitude of the convective flux from the separated leading-edge shear layer, suggesting that the secondary vorticity plays a significant role in regulating the strength of the primary vortex. This phenomenon is examined in the present case, and the physical mechanisms governing the growth and evolution of the dynamic stall vortices are explored. This work was supported by the Air Force Office of Scientific Research through the Flow Interactions and Control Program monitored by Dr. Douglas Smith, and through the 2014 AFOSR/ASEE Summer Faculty Fellowship Program (JA and JB).

  5. Simulasi Numerik Dynamic Stall Pada Airfoil Yang Berosilasi

    Directory of Open Access Journals (Sweden)

    Galih S.T.A. Bangga

    2012-09-01

    Full Text Available Kebutuhan analisa pada sudu helikopter, kompresor, kincir angin dan struktur streamline lainya yang beroperasi pada angle of attack yang tinggi dan melibatkan instationary effects yang disebut dynamic stall menjadi semakin penting. Fenomena ini ditandai dengan naiknya dynamic lift melewati static lift maksimum pada critical static stall angle, vortex yang terbentuk pada leading edge mengakibatkan naiknya suction contribution yang kemudian terkonveksi sepanjang permukaan hingga mencapai trailling edge diikuti terbentuknya trailling edge vortex yang menunjukkan terjadinya lift stall. Fenomena ini sangat berbahaya terhadap struktur airfoil itu sendiri. Secara umum, beban fatique yang ditimbulkan oleh adanya efek histerisis karena fluktuasi gaya lift akibat induksi vibrasi lebih besar dibandingkan kondisi statis. Simulasi numerik dilakukan secara 2D dengan menggunakan profil Boeing-Vertol V23010-1.58 pada α0 = 14.92°. Standard-kω dan SST-kω digunakan sebagai URANS turbulence modelling. Model osilasi dari airfoil disusun dalam suatu user defined function (UDF. Gerakan meshing beserta airfoil diakomodasi dengan menggunakan dynamic mesh approach. Simulasi numerik menunjukkan bahwa, model SST-kω menunjukkan performa yang lebih baik dibandingkan dengan Standard-kω. Fenomena travelling vortex yang terjadi mampu ditangkap dengan baik, meski pada angle of attack yang tinggi URANS turbulence model gagal memprediksikan fenomena yang terjadi karena dominasi efek 3D.

  6. Prediction of dynamic loads and induced vibrations in stall

    Energy Technology Data Exchange (ETDEWEB)

    Thirstrup Petersen, J.; Aagaard Madsen, H. [Risoe National Lab. (Denmark); Bjoerck, A. [Aeronautical Research Inst. of Sweden (Sweden); Enevoldsen, P. [Bonus Energy A/S (Denmark); Oeye, S. [The Technical Univ. of Denmark (Denmark); Ganander, H. [Teknikgruppen AB (Sweden); Winkelaar, D. [Netherlands Energy Research Foundation (Netherlands)

    1998-05-01

    Results from research in an EC Joule-III project and from national projects are presented. The objectives are improvement of design methods for stall regulated wind turbines with emphasis on stall induced vibrations and dynamic stall. The primary concern is limitation of the edgewise vibrations in the fundamental blade natural mode shape, which have caused trouble on modern wind turbines of approximate size 500 kW nominal power and 40 m rotor diameter. A theoretical study of quasi-steady aerodynamics confirms that the vibrations are driven basically by energy supplied from the aerodynamic forces during stalled operation. This energy exchange is equivalent to negative aerodynamic damping. The theoretical approach identifies the main parameters controlling the phenomenon. These parameters describe the steady and the dynamic airfoil characteristics, the overall aerodynamic layout of the blade, e.g. chord length and twist, the structural properties of the blade, e.g. structural damping and properties controlling the resulting vibration direction. Furthermore, full aeroelastic calculations and comparison with measurements show that the properties of the supporting structure, i.e. the main shaft, the nacelle and the tower, are important, as the global vibration of the rotor on its support may exchange energy with the blade vibration, when the blade natural frequency is close to one of the frequencies of the coupled rotor tilt-yaw mode shapes, usually denoted the global rotor whirl frequencies. It is confirmed that the influence of changing the primary design parameters can be determined by use of qualified aeroelastic calculations. Presented design guidelines therefore build on both the simple quasi-steady models, which can be used for the preliminary choice of the design variables mentioned above, and on full aeroelastic calculations. The aeroelastic calculations refine the design basis and should be used for choosing the final design variables and for final

  7. Wider stall space affects behavior, lesion scores, and productivity of gestating sows.

    Science.gov (United States)

    Salak-Johnson, J L; DeDecker, A E; Levitin, H A; McGarry, B M

    2015-10-01

    Limited space allowance within the standard gestation stall is an important welfare concern because it restricts the ability of the sow to make postural adjustments and hinders her ability to perform natural behaviors. Therefore, we evaluated the impacts of increasing stall space and/or providing sows the freedom to access a small pen area on sow well-being using multiple welfare metrics. A total of 96 primi- and multiparous crossbred sows were randomly assigned in groups of 4 sows/treatment across 8 replicates to 1 of 3 stall treatments (TRT): standard stall (CTL; dimensions: 61 by 216 cm), width-adjustable stall (flex stall [FLX]; dimensions: adjustable width of 56 to 79 cm by 216 cm), or an individual walk-in/lock-in stall with access to a small communal open-pen area at the rear of the stall (free-access stall [FAS]; dimensions: 69 by 226 cm). Lesion scores, behavior, and immune and productivity traits were measured at various gestational days throughout the study. Total lesion scores were greatest for sows in FAS and least for sows in FLX ( pregnancy progressed, lesion scores increased among sows in CTL ( postural behaviors and sham chew behavior were affected by TRT ( changes in postural behaviors, lesion severity scores, and other sow traits. Moreover, compromised welfare measures found among sows in various stall environments may be partly attributed to the specific constraints of each stall system such as restricted stall space in CTL, insufficient floor space in the open-pen area of the FAS system, and gate design of the FLX (e.g., direction of bars and feeder space). These results also indicate that parity and gestational day are additional factors that may exacerbate the effects of restricted stall space or insufficient pen space, further compromising sow well-being.

  8. Precautions against axial fan stall in reactor building to Tianwan NPP

    International Nuclear Information System (INIS)

    Liu Chunlong; Pei Junmin

    2011-01-01

    The paper introduces the mechanism and harm of rotating stall of axial fans, analyzes the necessity for prevention against axial fan stall in reactor building of Tianwan NPP, introduces the precautions, and then makes an assessment on anti-stall effect of flow separators. It can provide reference for model-selection or reconstruction of similar fans in power stations, and for operation and maintenance of axial fans. (authors)

  9. Comparison of Different Stall Conditions in Axial Flow Compressor Using Analytic Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Arshad Ali

    2017-12-01

    Full Text Available The rotating stall inception data analysis using Analytic Wavelet Transform (AWT in a low-speed axial compressor was presented in the authors’ previous studies [1], [2]. These studies focused on the detection of instability inception in an axial flow compressor when it enters into the instability regime due to the modal type of stall perturbation. In this paper, the effectiveness of AWT is further studied by applying it under different testing conditions. In order to examine the results of AWT on highly sampled data, at first, the stall data were acquired at a high sampling frequency and the results were compared with the conventional filtered signals. Secondly, the AWT analysis of stall data was carried out for the condition when compressor experienced a spike type rotating stall disturbance. The stall inception information obtained from the AWT analysis was then compared with the commonly used stall detection techniques. The results show that AWT is equally beneficial for the diagnostic of compressor instability regardless of the data sampling rate and represents an outstanding ability to detect stall disturbance irrespective of the type of stall precursor, i.e. the modal wave or spike.

  10. Enhancing BEM simulations of a stalled wind turbine using a 3D correction model

    Science.gov (United States)

    Bangga, Galih; Hutomo, Go; Syawitri, Taurista; Kusumadewi, Tri; Oktavia, Winda; Sabila, Ahmad; Setiadi, Herlambang; Faisal, Muhamad; Hendranata, Yongki; Lastomo, Dwi; Putra, Louis; Kristiadi, Stefanus; Bumi, Ilmi

    2018-03-01

    Nowadays wind turbine rotors are usually employed with pitch control mechanisms to avoid deep stall conditions. Despite that, wind turbines often operate under pitch fault situation causing massive flow separation to occur. Pure Blade Element Momentum (BEM) approaches are not designed for this situation and inaccurate load predictions are already expected. In the present studies, BEM predictions are improved through the inclusion of a stall delay model for a wind turbine rotor operating under pitch fault situation of -2.3° towards stall. The accuracy of the stall delay model is assessed by comparing the results with available Computational Fluid Dynamics (CFD) simulations data.

  11. Numerical simulation of the RISOe1-airfoil dynamic stall

    Energy Technology Data Exchange (ETDEWEB)

    Bertagnolio, F.; Soerensen, N. [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark)

    1997-12-31

    In this paper we are concerned with the numerical computation of the dynamic stall that occur in the viscous flowfield over an airfoil. These results are compared to experimental data that were obtained with the new designed RISOe1-airfoil, both for a motionless airfoil and for a pitching motion. Moreover, we present some numerical computations of the plunging and lead-lag motions. We also investigate the possibility of using the pitching motion to simulate the plunging and lead-lag situations. (au)

  12. El departamento musical Disney : las Silly Symphonies y Carl Stalling

    OpenAIRE

    Duarte del Moral, Marina

    2014-01-01

    La historia de la animación tiene un nombre propio: Walt Disney. Gracias a su experimentación en diversos campos de esta materia, Disney consigue desarrollar la animación y su universo de una forma perseverante y continua, adaptándose a los diversos cambios producidos desde el nacimiento de ésta, reinventando una y otra vez el sector y añadiendo su toque mágico a la personalidad de cada personaje y cada obra. En este camino no está solo gracias al trabajo de genios como Carl Stalling, que apo...

  13. The FFA dynamic stall model. The Beddoes-Leishman dynamic stall model modified for lead-lag oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerck, A. [FFA, The Aeronautical Research Institute of Sweden, Bromma (Sweden)

    1997-08-01

    For calculations of the dynamics of wind turbines the inclusion of a dynamic stall model is necessary in order to obtain reliable results at high winds. For blade vibrations in the lead-lag motion the velocity relative to the blade will vary in time. In the present paper modifications to the Beddoes-Leishman model is presented in order to improve the model for calculations of cases with a varying relative velocity. Comparisons with measurement are also shown and the influence on the calculated aerodynamic damping by the modifications are investigated. (au)

  14. Ingestive behavior of lambs confined in individual and group stalls.

    Science.gov (United States)

    Filho, A Eustáquio; Carvalho, G G P; Pires, A J V; Silva, R R; Santos, P E F; Murta, R M; Pereira, F M

    2014-02-01

    The experiment was conducted to evaluate the ingestive behavior of lambs confined in individual and group stalls. We used thirty-four lambs in their growing phase, aged an average of three months, with mean initial live weight of 17.8±5.2 kg. They were allotted in a completely randomized design with 24 animals kept in individual stalls and 10 animals confined as a group. The experiment lasted for a total of 74 days, and the first 14 days were dedicated to the animals' adaption to the management, facilities and diets. The data collection period lasted 60 days, divided into three 20-d periods for the behavior evaluation. The animals were subjected to five days of visual observation during the experiment period, by the quantification of 24 h a day, with evaluations on the 15th day of each period and an interim evaluation consisting of two consecutive days on the 30th and 31st day of the experiment. The animals confined as a group consumed less (pbehavior.

  15. A.C. Plasma Anemometer for Axial Compressor Stall Warning

    Science.gov (United States)

    Matlis, Eric; Cameron, Joshua; Morris, Scott; Corke, Thomas

    2007-11-01

    Compressor sections of turbo jet engines are subject to stall and surge as a result of flow instabilities that occur upstream of the compressor rotor. One of the instability modes that contributes to compressor surge is the so-called `spike' mode of stall inception. It has been shown that this mode of instability can be predicted before onset by performing real-time statistical auto-correlation measurements of the blade-passing pressure characteristic at the mid-chord location of the rotor. These measurements are performed with pressure sensors or hot-wires that are too fragile for a full-scale compressor. We have developed a sensor that can survive the vibration and temperatures of a full-scale rig while providing the bandwidth necessary to resolve the blade passage signature required by this coherence technique. This sensor, called the Plasma Anemometer, provides high-bandwith point measurements of velocity or pressure fluctuations with unparalleled mechanical robustness and resistance to vibration and thermal effects.

  16. A Multi-Fork Z-Axis Quartz Micromachined Gyroscope

    Science.gov (United States)

    Feng, Lihui; Zhao, Ke; Sun, Yunan; Cui, Jianmin; Cui, Fang; Yang, Aiying

    2013-01-01

    A novel multi-fork z-axis gyroscope is presented in this paper. Different from traditional quartz gyroscopes, the lateral electrodes of the sense beam can be arranged in simple patterns; as a result, the fabrication is simplified. High sensitivity is achieved by the multi-fork design. The working principles are introduced, while the finite element method (FEM) is used to simulate the modal and sensitivity. A quartz fork is fabricated, and a prototype is assembled. Impedance testing shows that the drive frequency and sense frequency are similar to the simulations, and the quality factor is approximately 10,000 in air. The scale factor is measured to be 18.134 mV/(°/s) and the nonlinearity is 0.40% in a full-scale input range of ±250 °/s. PMID:24048339

  17. Evaluating Classroom Interaction with the iPad®: An Updated Stalling's Tool

    Science.gov (United States)

    MacKinnon, Gregory; Schep, Lourens; Borden, Lisa Lunney; Murray-Orr, Anne; Orr, Jeff; MacKinnon, Paula

    2016-01-01

    A large study of classrooms in the Caribbean context necessitated the use of a validated classroom observation tool. In practice, the paper-version Stalling's instrument (Stallings & Kaskowitz 1974) presented specific challenges with respect to (a) facile data collection and (b) qualitative observations of classrooms. In response to these…

  18. Simulation of Entropy Generation under Stall Conditions in a Centrifugal Fan

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2014-06-01

    Full Text Available Rotating stalls are generally the first instability met in turbomachinery, before surges. This 3D phenomenon is characterized by one or more stalled flow cells which rotate at a fraction of the impeller speed. The goal of the present work is to shed some light on the entropy generation in a centrifugal fan under rotating stall conditions. A numerical simulation of entropy generation is carried out with the ANSYS Fluent software which solves the Navier-Stokes equations and user defined function (UDF. The entropy generation characteristics in the centrifugal fan for five typical conditions are presented and discussed, involving the design condition, conditions on occurrence and development of stall inception, the rotating stall conditions with two throttle coefficients. The results show that the entropy generation increases after the occurrence of stall inception. The high entropy generation areas move along the circumferential and axial directions, and finally merge into one stall cell. The entropy generation rate during circumferential propagation of the stall cell is also discussed, showing that the entropy generation history is similar to sine curves in impeller and volute, and the volute tongue has a great influence on entropy generation in the centrifugal fan.

  19. Hydraulic, geomorphic, and trout habitat conditions of the Lake Fork of the Gunnison River in Hinsdale County, Lake City, Colorado, Water Years 2010-2011

    Science.gov (United States)

    Williams, Cory A.; Richards, Rodney J.; Schaffrath, Keelin R.

    2015-01-01

    Channel rehabilitation, or reconfiguration, to mitigate a variety of riverine problems has become a common practice in the western United States. However, additional work to monitor and assess the channel response to, and the effectiveness of, these modifications over longer periods of time (decadal or longer) is still needed. The Lake Fork of the Gunnison River has been an area of active channel modification to accommodate the needs of the Lake City community since the 1950s. The Lake Fork Valley Conservancy District began a planning process to assess restoration options for a reach of the Lake Fork in Lake City to enhance hydraulic and ecologic characteristics of the reach. Geomorphic channel form is affected by land-use changes within the basin and geologic controls within the reach. The historic channel was defined as a dynamic, braided channel with an active flood plain. This can result in a natural tendency for the channel to braid. A braided channel can affect channel stability of reconfigured reaches when a single-thread meandering channel is imposed on the stream. The U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board and Colorado River Water Conservation District, began a study in 2010 to quantify existing hydraulic and habitat conditions for a reach of the Lake Fork of the Gunnison River in Lake City, Colorado. The purpose of this report is to quantify existing Lake Fork hydraulic and habitat conditions and establish a baseline against which post-reconfiguration conditions can be compared. This report (1) quantifies the existing hydraulic and geomorphic conditions in a 1.1-kilometer section of the Lake Fork at Lake City that has been proposed as a location for future channel-rehabilitation efforts, (2) characterizes the habitat suitability of the reach for two trout species based on physical conditions within the stream, and (3) characterizes the current riparian canopy density.

  20. Forked and Integrated Variants In An Open-Source Firmware Project

    DEFF Research Database (Denmark)

    Stanciulescu, Stefan; Schulze, Sandro; Wasowski, Andrzej

    2015-01-01

    and interactive source management platforms such as Github. We study advantages and disadvantages of forking using the case of Marlin, an open source firmware for 3D printers. We find that many problems and advantages of cloning do translate to forking. Interestingly, the Marlin community uses both forking...

  1. 77 FR 71611 - Land Acquisitions; North Fork Rancheria of Mono Indians of California

    Science.gov (United States)

    2012-12-03

    ... Bureau of Indian Affairs Land Acquisitions; North Fork Rancheria of Mono Indians of California AGENCY... trust for gaming purposes for the North Fork Rancheria of Mono Indians of California on November 26... land in trust for the North Fork Rancheria of Mono Indians of California under the authority of the...

  2. 77 FR 39675 - Wallowa-Whitman National Forest, Baker County, OR; North Fork Burnt River Mining

    Science.gov (United States)

    2012-07-05

    ...-Whitman National Forest, Baker County, OR; North Fork Burnt River Mining AGENCY: Forest Service, USDA... North Fork Burnt River Mining Record of Decision will replace and supercede the 2004 North Fork Burnt River Mining Record of Decision only where necessary to address the inadequacies identified by the court...

  3. Regulation of sister chromosome cohesion by the replication fork tracking protein SeqA.

    Science.gov (United States)

    Joshi, Mohan C; Magnan, David; Montminy, Timothy P; Lies, Mark; Stepankiw, Nicholas; Bates, David

    2013-01-01

    Analogously to chromosome cohesion in eukaryotes, newly replicated DNA in E. coli is held together by inter-sister linkages before partitioning into daughter nucleoids. In both cases, initial joining is apparently mediated by DNA catenation, in which replication-induced positive supercoils diffuse behind the fork, causing newly replicated duplexes to twist around each other. Type-II topoisomerase-catalyzed sister separation is delayed by the well-characterized cohesin complex in eukaryotes, but cohesion control in E. coli is not currently understood. We report that the abundant fork tracking protein SeqA is a strong positive regulator of cohesion, and is responsible for markedly prolonged cohesion observed at "snap" loci. Epistasis analysis suggests that SeqA stabilizes cohesion by antagonizing Topo IV-mediated sister resolution, and possibly also by a direct bridging mechanism. We show that variable cohesion observed along the E. coli chromosome is caused by differential SeqA binding, with oriC and snap loci binding disproportionally more SeqA. We propose that SeqA binding results in loose inter-duplex junctions that are resistant to Topo IV cleavage. Lastly, reducing cohesion by genetic manipulation of Topo IV or SeqA resulted in dramatically slowed sister locus separation and poor nucleoid partitioning, indicating that cohesion has a prominent role in chromosome segregation.

  4. Optimal parameters for the FFA-Beddoes dynamic stall model

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerck, A.; Mert, M. [FFA, The Aeronautical Research Institute of Sweden, Bromma (Sweden); Madsen, H.A. [Risoe National Lab., Roskilde (Denmark)

    1999-03-01

    Unsteady aerodynamic effects, like dynamic stall, must be considered in calculation of dynamic forces for wind turbines. Models incorporated in aero-elastic programs are of semi-empirical nature. Resulting aerodynamic forces therefore depend on values used for the semi-empiricial parameters. In this paper a study of finding appropriate parameters to use with the Beddoes-Leishman model is discussed. Minimisation of the `tracking error` between results from 2D wind tunnel tests and simulation with the model is used to find optimum values for the parameters. The resulting optimum parameters show a large variation from case to case. Using these different sets of optimum parameters in the calculation of blade vibrations, give rise to quite different predictions of aerodynamic damping which is discussed. (au)

  5. Proposed Chevron Tengiz venture stalls amid Soviet political squabble

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This paper reports on the status of foreign investment in Soviet oil and gas joint ventures which has reached a critical juncture. Just as the U.S. is considering granting most favored nation trade status to the U.S.S.R., the joint venture petroleum deal seen as the litmus test for such deals-Chevron Corp.'s proposed addition of supergiant Tengiz oil field to its Caspian Sea joint venture-has stalled amid controversy. Unconfirmed reports from Soviet officials and other foreign joint venture participants in the U.S.S.R. have Chevron pulling out of the long negotiated, multibillion dollar project after the Soviets rejected the company's terms. Chevron, however, insists the project is still alive

  6. Resonance Experiments Using AFO Instead of Tuning Fork

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 11. Resonance Experiments Using AFO Instead of Tuning Fork. Deepak H Gadani. Classroom Volume 16 Issue 11 November 2011 pp 1053-1060. Fulltext. Click here to view fulltext PDF. Permanent link:

  7. Shrub-steppe vegetation trend, Middle Fork Salmon River, Idaho

    Science.gov (United States)

    James M. Peek

    2000-01-01

    The Middle Fork Salmon River drainage of the Frank Church River-Of-No-Return Wilderness has a history of livetock grazing from 1890 to 1950, and changes in grazing pressure from native ungulates. High mule deer (Odocoileus hemionus) populations occurred between 1940 and 1960, and high elk (Cervus elaphus) populations occurred in...

  8. Comparative Study of Transcriptome Profiles of Mouse Livers and Skins Infected by Fork-Tailed or Non-Fork-Tailed Schistosoma japonicum

    Directory of Open Access Journals (Sweden)

    Yan Yang

    2017-08-01

    Full Text Available Schistosoma japonicum (S. japonicum is a worldwide spread pathogen which penetrates host skin and then induces several diseases in infected host, such as fibrosis, formation of granulomas, hepatocirrhosis, and hepatomegaly. In present study, for the first time, transcriptomic profiles of mouse livers and skins infected by fork-tailed S. japonicum cercaria or non-fork-tailed S. japonicum cercaria were analyzed by using RNA-seq. The present findings demonstrated that transcriptomic landscapes of livers and skins infected by fork-tailed S. japonicum cercaria or non-fork-tailed S. japonicum cercaria were different. S. japonicum has great influence on hepatic metabolic processes. Fork-tailed S. japonicum cercaria upregulated hepatic metabolic processes, while non-fork-tailed S. japonicum cercaria downregulated hepatic metabolic processes. For the metabolism process or the metabolism enzyme expressional change, the pharmacokinetics of host could be changed during S. japonicum infection, regardless the biotypes of S. japonicum cercariae. The changes of infected skins focused on upregulation of immune response. During the S. japonicum skin infection period, fork-tailed S. japonicum cercaria infection induced stronger immune response comparing with that immune response triggered by non-fork-tailed S. japonicum cercaria. The transcription factor enrichment analysis showed that Irf7, Stat1 and Stat2 could play important roles in gene regulation during fork-tailed S. japonicum cercaria infection.

  9. Analysis of Low Speed Stall Aerodynamics of a Swept Wing with Laminar Flow Glove

    Science.gov (United States)

    Bui, Trong T.

    2014-01-01

    Reynolds-Averaged Navier-Stokes (RANS) computational fluid dynamics (CFD) analysis was conducted to study the low-speed stall aerodynamics of a GIII aircraft's swept wing modified with a laminar-flow wing glove. The stall aerodynamics of the gloved wing were analyzed and compared with the unmodified wing for the flight speed of 120 knots and altitude of 2300 ft above mean sea level (MSL). The Star-CCM+ polyhedral unstructured CFD code was first validated for wing stall predictions using the wing-body geometry from the First American Institute of Aeronautics and Astronautics (AIAA) CFD High-Lift Prediction Workshop. It was found that the Star-CCM+ CFD code can produce results that are within the scattering of other CFD codes considered at the workshop. In particular, the Star-CCM+ CFD code was able to predict wing stall for the AIAA wing-body geometry to within 1 degree of angle of attack as compared to benchmark wind-tunnel test data. Current results show that the addition of the laminar-flow wing glove causes the gloved wing to stall much earlier than the unmodified wing. Furthermore, the gloved wing has a different stall characteristic than the clean wing, with no sharp lift drop-off at stall for the gloved wing.

  10. Analysis of Low-Speed Stall Aerodynamics of a Swept Wing with Laminar-Flow Glove

    Science.gov (United States)

    Bui, Trong T.

    2014-01-01

    Reynolds-Averaged Navier-Stokes (RANS) computational fluid dynamics (CFD) analysis was conducted to study the low-speed stall aerodynamics of a GIII aircraft's swept wing modified with a laminar-flow wing glove. The stall aerodynamics of the gloved wing were analyzed and compared with the unmodified wing for the flight speed of 120 knots and altitude of 2300 ft above mean sea level (MSL). The Star-CCM+ polyhedral unstructured CFD code was first validated for wing stall predictions using the wing-body geometry from the First American Institute of Aeronautics and Astronautics (AIAA) CFD High-Lift Prediction Workshop. It was found that the Star-CCM+ CFD code can produce results that are within the scattering of other CFD codes considered at the workshop. In particular, the Star-CCM+ CFD code was able to predict wing stall for the AIAA wing-body geometry to within 1 degree of angle of attack as compared to benchmark wind-tunnel test data. Current results show that the addition of the laminar-flow wing glove causes the gloved wing to stall much earlier than the unmodified wing. Furthermore, the gloved wing has a different stall characteristic than the clean wing, with no sharp lift drop-off at stall for the gloved wing.

  11. Watershed characterization for precipitation-runoff modeling system, north fork, American River and east fork, Carson River watersheds, California

    Science.gov (United States)

    Smith, J. LaRue; Reece, Brian D.

    1995-01-01

    As part of its Global Change Hydrology Program, the U.S. Geological Survey (USGS) is investigating the potential effects of climate change on the water resources of several river basins in the United States. The American River Basin in California represents the windward slope of the north-central Sierra Nevada, and the California part of the Carson River Basin, most of which is in Nevada, represents the leeward slope. Parts of the American River and Carson River Basins—the North Fork American River and East Fork Carson River watersheds, both in California—were studied to determine the sensitivity of water resources to potential climate change. The water resources of both basins are derived primarily from snowmelt. A geographic information system (GIS) data base has been created to facilitate paired-basin analysis. The GIS data base incorporates (1) land-surface data, which include elevation, land use and land cover, soil type, and geology; (2) hydrologic data, such as stream networks and streamflow-gaging stations; and (3) climatic data, such as snow-course, snow-telemetry, radiosonde, and meteorological data. Precipitation-runoff models were developed and calibrated for the North Fork watershed within the American River Basin and for the East Fork watershed within the Carson River Basin. (These watersheds were selected to represent the climatic and physiographic variability of the two larger basins.) Synthesized climate scenarios then were used in the model to predict potential effects of climate change.

  12. Analysis of Low-Speed Stall Aerodynamics of a Business Jets Wing Using STAR-CCM+

    Science.gov (United States)

    Bui, Trong

    2016-01-01

    Reynolds-Averaged Navier-Stokes (RANS) computational fluid dynamics (CFD) analysis was conducted: to study the low-speed stall aerodynamics of a GIII aircrafts swept wing modified with (1) a laminar-flow wing glove, or (2) a seamless flap. The stall aerodynamics of these two different wing configurations were analyzed and compared with the unmodified baseline wing for low-speed flight. The Star-CCM+ polyhedral unstructured CFD code was first validated for wing stall predictions using the wing-body geometry from the First AIAA CFD High-Lift Prediction Workshop.

  13. 2'-O-methyl-modified anti-MDR1 fork-siRNA duplexes exhibiting high nuclease resistance and prolonged silencing activity.

    Science.gov (United States)

    Petrova Kruglova, Natalya S; Meschaninova, Mariya I; Venyaminova, Alya G; Zenkova, Marina A; Vlassov, Valentin V; Chernolovskaya, Elena L

    2010-12-01

    The thermodynamic asymmetry of siRNA duplexes determines their silencing activity. Favorable asymmetry can be achieved by incorporation of mismatches into the 3' part of the sense strand, providing fork-siRNAs, which exhibit higher silencing activity and higher sensitivity to nucleases. Recently, we found that selective 2'-O-methyl modifications of the nuclease-sensitive sites of siRNA significantly improve its nuclease resistance without substantial loss of silencing activity. Here, we examined the impact of nucleotide mismatches and the number and location of 2'-O-methyl modifications on the silencing activity and nuclease resistance of anti-MDR1 siRNAs. We found that both nonmodified and selectively modified fork-siRNAs with 4 mismatches at the 3' end of the sense strand suppress the expression of target gene at lower effective concentrations than the parent siRNAs with classical duplex design. The selective modification of nuclease-sensitive sites significantly improved the stability of fork-siRNAs in the presence of serum. The selectively modified fork-siRNA duplexes provided inhibitory effect over a period of 12 days posttransfection, whereas the gene silencing activity of the nonmodified analogs expired within 6 days. Thus, selective chemical modifications and structural alteration of siRNA duplexes improve their silencing properties and significantly prolong the duration of their silencing effect.

  14. DNA Polymerase III, but Not Polymerase IV, Must Be Bound to a τ-Containing DnaX Complex to Enable Exchange into Replication Forks.

    Science.gov (United States)

    Yuan, Quan; Dohrmann, Paul R; Sutton, Mark D; McHenry, Charles S

    2016-05-27

    Examples of dynamic polymerase exchange have been previously characterized in model systems provided by coliphages T4 and T7. Using a dominant negative D403E polymerase (Pol) III α that can form initiation complexes and sequester primer termini but not elongate, we investigated the possibility of exchange at the Escherichia coli replication fork on a rolling circle template. Unlike other systems, addition of polymerase alone did not lead to exchange. Only when D403E Pol III was bound to a τ-containing DnaX complex did exchange occur. In contrast, addition of Pol IV led to rapid exchange in the absence of bound DnaX complex. Examination of Pol III* with varying composition of τ or the alternative shorter dnaX translation product γ showed that τ-, τ2-, or τ3-DnaX complexes supported equivalent levels of synthesis, identical Okazaki fragment size, and gaps between fragments, possessed the ability to challenge pre-established replication forks, and displayed equivalent susceptibility to challenge by exogenous D403E Pol III*. These findings reveal that redundant interactions at the replication fork must stabilize complexes containing only one τ. Previously, it was thought that at least two τs in the trimeric DnaX complex were required to couple the leading and lagging strand polymerases at the replication fork. Possible mechanisms of exchange are discussed. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Stalling HIV through social marketing: prospects in Pakistan.

    Science.gov (United States)

    Husain, Sara; Shaikh, Babar T

    2005-07-01

    Over the last two decades HIV/AIDS has evolved from a series of interesting case-reports to a growing epidemic that threatens the entire world. It is feared to cause devastation among large pockets of populations and may roll back more than thirty years of public health achievements. This killer disease has been more amenable to behavioral change than by provision of curative services and attempts are being made to educate the public about this threat. Various techniques of promotion have been tried through out the world including television dramas/soaps, mass media and school curricula. Social marketing is an evolving strategy used to influence human behavior and choices. By using the principles of marketing and promoting behavior as a product, social marketers attempt to understand the dynamics of human behaviour and devise messages and products to change, modify, accept or reject unsafe behaviors or practices. Thus, social marketers provide an effective force to combat the spread of HIV and may serve to be invaluable allies in health promotion efforts. In a complex and diversified cultural milieu of Pakistan, social marketing can have a significant impact on health determinants and the conditions that will facilitate the adoption of health-oriented behaviors and practices. This paper gives an account of the elements needed for the success of a health promotion strategy adopted in a developing country and makes a case for social marketing to be adopted as the lead strategy for stalling HIV/AIDS in Pakistan.

  16. Initial design of a stall-controlled wind turbine rotor

    Energy Technology Data Exchange (ETDEWEB)

    Nygaard, T.A. [Inst. for Energiteknikk, Kjeller (Norway)

    1997-08-01

    A model intended for initial design of stall-controlled wind turbine rotors is described. The user specifies relative radial position of an arbitrary number of airfoil sections, referring to a data file containing lift-and drag curves. The data file is on the same format as used in the commercial blade-element code BLADES-/2/, where lift- and drag coefficients are interpolated from tables as function of Reynolds number, relative thickness and angle of attack. The user can set constraints on a selection of the following: Maximum power; Maximum thrust in operation; Maximum root bending moment in operation; Extreme root bending moment, parked rotor; Tip speed; Upper and lower bounds on optimisation variables. The optimisation variables can be selected from: Blade radius; Rotational speed; Chord and twist at an arbitrary number of radial positions. The user can chose linear chord distribution and a hyperbola-like twist distribution to ensure smooth planform and twist, or cubic spline interpolation for one or both. The aerodynamic model is based on classical strip theory with Prandtl tip loss correction, supplemented by empirical data for high induction factors. (EG)

  17. Cow preference and usage of free stalls compared with an open pack area.

    Science.gov (United States)

    Fregonesi, J A; von Keyserlingk, M A G; Weary, D M

    2009-11-01

    Free-stall housing systems are designed to provide a comfortable and hygienic lying area, but some aspects of stall design may restrict usage by cows. The aim of this study was to compare free-stall housing with a comparable lying area (open pack) without stall partitions. We predicted that cows would spend more time lying down and standing in the bedded area when provided access to an open pack than when in free stalls. We also predicted that cows would spend less time standing outside of the lying area and less time perching with the front 2 hooves in the lying area when using the open pack. Groups (n = 8) of 12 cows each were provided access to either the open pack or stalls. After a 7-d adaptation period, each group was tested sequentially in the 2 treatments for 3 d each. This no-choice phase was followed by an 8-d choice phase during which cows had simultaneous access to both treatments. During the no-choice phase, cows spent more time lying down (13.03 +/- 0.24 vs. 12.48 +/- 0.24 h/d) and standing with all 4 hooves in the bedded area (0.96 +/- 0.12 vs. 0.41 +/- 0.12 h/d) of the open pack than in the stalls. During the choice phase, cows spent more time lying down (7.20 +/- 0.29 vs. 5.86 +/- 0.29 h/d) and standing with all 4 hooves in the bedded area (0.58 +/- 0.07 vs. 0.12 +/- 0.07 h/d) of the open pack than in the stalls. In both the no-choice (1.66 +/- 0.24 vs. 0.55 +/- 0.24 h/d) and choice (0.55 +/- 0.07 vs. 0.29 +/- 0.07 h/d) phases, cows spent more time standing with just 2 hooves in the stalls than in the open pack. In conclusion, cows spent more time lying and standing with all 4 hooves in the bedded open pack than in the stalls. Additionally, cows spent more time standing in the alley and standing with just the front 2 hooves on the bedding in the stalls than in the bedded open pack; increased standing time on wet concrete is a known risk factor for lameness.

  18. Dynamic stall characterization using modal analysis of phase-averaged pressure distributions

    Science.gov (United States)

    Harms, Tanner; Nikoueeyan, Pourya; Naughton, Jonathan

    2017-11-01

    Dynamic stall characterization by means of surface pressure measurements can simplify the time and cost associated with experimental investigation of unsteady airfoil aerodynamics. A unique test capability has been developed at University of Wyoming over the past few years that allows for time and cost efficient measurement of dynamic stall. A variety of rotorcraft and wind turbine airfoils have been tested under a variety of pitch oscillation conditions resulting in a range of dynamic stall behavior. Formation, development and separation of different flow structures are responsible for the complex aerodynamic loading behavior experienced during dynamic stall. These structures have unique signatures on the pressure distribution over the airfoil. This work investigates the statistical behavior of phase-averaged pressure distribution for different types of dynamic stall by means of modal analysis. The use of different modes to identify specific flow structures is being investigated. The use of these modes for different types of dynamic stall can provide a new approach for understanding and categorizing these flows. This work uses airfoil data acquired under Army contract W911W60160C-0021, DOE Grant DE-SC0001261, and a gift from BP Alternative Energy North America, Inc.

  19. High-Speed Experiments on Combustion-Powered Actuation for Dynamic Stall Suppression

    Science.gov (United States)

    Matalanis, Claude; Bowles, Patrick; Lorber, Peter; Crittenden, Thomas; Glezer, Ari; Schaeffler, Norman; Min, Byung-Young; Jee, Solkeun; Kuczek, Andrzej; Wake, Brian

    2016-01-01

    This work documents high-speed wind tunnel experiments conducted on a pitching airfoil equipped with an array of combustion-powered actuators (COMPACT). The main objective of these experiments was to demonstrate the stall-suppression capability of COMPACT on a high-lift rotorcraft airfoil, the VR-12, at relevant Mach numbers. Through dynamic pressure measurements at the airfoil surface it was shown that COMPACT can positively affect the stall behavior of the VR-12 at Mach numbers up to 0.4. Static airfoil results demonstrated 25% and 50% increases in post-stall lift at Mach numbers of 0.4 and 0.3, respectively. Deep dynamic stall results showed cycle-averaged lift coefficient increases up to 11% at Mach 0.4. Furthermore, it was shown that these benefits could be achieved with relatively few pulses during down-stroke and with no need to pre-anticipate the stall event. The flow mechanisms responsible for stall suppression were investigated using particle image velocimetry.

  20. Experimental Investigation of Stall Inception Mechanisms of Low Speed Contra Rotating Axial Flow Fan Stage

    Directory of Open Access Journals (Sweden)

    Tegegn Dejene Toge

    2015-01-01

    Full Text Available The present paper is an attempt in understanding the stall inception mechanism in a low speed, contra rotating axial flow fan stage, using wavelet transforms. The rotors used in this study have relatively large tip gap (about 3% of the blade span and aspect ratio of 3. The study was carried out near stall and at stall mass flow conditions for different speed ratios of rotor-2 to rotor-1. Unsteady pressure data from the casing wall mounted sensors are used to understand the stall inception mechanism. The wavelet transform clearly indicates that stall inception occurs mainly through long length scale disturbances for both rotors. It also reveals that short length disturbances occur simultaneously or intermittently in the case of rotor-1. The analysis shows the presence of a strong modal disturbance with 25–80% of the rotor frequency in the case of rotor-1 at the stall mass flow for all the speed combinations studied. The most interesting thing observed in the present study is that the frequency amplitude of the disturbance level is very small for both rotors.

  1. Capitalizing on disaster: Establishing chromatin specificity behind the replication fork.

    Science.gov (United States)

    Ramachandran, Srinivas; Ahmad, Kami; Henikoff, Steven

    2017-04-01

    Eukaryotic genomes are packaged into nucleosomal chromatin, and genomic activity requires the precise localization of transcription factors, histone modifications and nucleosomes. Classic work described the progressive reassembly and maturation of bulk chromatin behind replication forks. More recent proteomics has detailed the molecular machines that accompany the replicative polymerase to promote rapid histone deposition onto the newly replicated DNA. However, localized chromatin features are transiently obliterated by DNA replication every S phase of the cell cycle. Genomic strategies now observe the rebuilding of locus-specific chromatin features, and reveal surprising delays in transcription factor binding behind replication forks. This implies that transient chromatin disorganization during replication is a central juncture for targeted transcription factor binding within genomes. We propose that transient occlusion of regulatory elements by disorganized nucleosomes during chromatin maturation enforces specificity of factor binding. © 2017 WILEY Periodicals, Inc.

  2. A vibrating quartz fork - a tool for cryogenic helium research

    Czech Academy of Sciences Publication Activity Database

    Blažková, Michaela; Člověčko, M.; Eltsov, V. B.; Gažo, E.; de Graaf, R.; Hosio, J.J.; Krusius, M.; Schmoranzer, D.; Schoepe, W.; Skrbek, Ladislav; Skyba, P.; Solntsev, R.E.; Vinen, W. F.

    2008-01-01

    Roč. 150, - (2008), s. 525-535 ISSN 0022-2291 R&D Projects: GA ČR GA202/05/0218 Grant - others:GAUK(CZ) 7953/2007; Transnational Access Programme(XE) RITA-CT-2003-505313 Institutional research plan: CEZ:AV0Z10100520 Keywords : normal 3He * superfluid 3He * superfluid 4He * turbulence, * cavitation * quartz tuning fork Subject RIV: BK - Fluid Dynamics Impact factor: 1.034, year: 2008

  3. Pitch Fork: A Novel tactile Digital Musical Instrument

    OpenAIRE

    Williams, Peter; Overholt, Daniel

    2017-01-01

    Pitch Fork is a prototype of an alternate, actuated digital musical instrument (DMI). It uses 5 infra-red and 4 piezoelectric sensors to control an additive synthesis engine. Iron bars are used as the physical point of contact in interaction with the aim of using material computation to control aspects of the digitally produced sound. This choice of material was also chosen to affect player experience. Sensor readings are relayed to a Macbook via an Arduino Mega. Mappings and audio output sig...

  4. East Fork Watershed Cooperative: Toward better system-scale ...

    Science.gov (United States)

    The East Fork Watershed Cooperative is a group intent on understanding how to best manage water quality in a large mixed-use Midwestern watershed system. The system contains a reservoir that serves as a source of drinking water and is popular for water recreation. The reservoir is experience harmful algal blooms. The system including the reservoir has become a significant case study for EPA ORD research and development. The Cooperative includes affiliates from the USACE, the OHIO EPA, the USGS, the USDA, and local Soil and Water Conservation districts as well as utility operators and water quality protection offices. The presentation includes a description of the water quality monitoring and modeling program in the watershed, followed by the results of using the watershed model to estimate the costs associated with nutrient reduction to Harsha Lake, and then ends with an explanation of temporal changes observed for important factors controlling harmful algae in Harsha Lake and how this lake relates to other reservoirs in the Ohio River Basin. This presentation is an invited contribution to the Ohio River Basin Water Quality Workshop sponsored by the US ACE and the US EPA. The presentation describes the activities of the East Fork Watershed Cooperative and the knowledge it has gained to help better manage a case study watershed system over the last few years. The East Fork of the Little Miami River is the focal watershed. It is a significant tributary to the Lit

  5. Timing, coordination, and rhythm: Acrobatics at the DNA replication fork

    KAUST Repository

    Hamdan, Samir

    2010-04-09

    In DNA replication, the antiparallel nature of the parental duplex imposes certain constraints on the activity of the DNA polymerases that synthesize new DNA. The leading-strand polymerase advances in a continuous fashion, but the lagging-strand polymerase is forced to restart at short intervals. In several prokaryotic systems studied so far, this problem is solved by the formation of a loop in the lagging strand of the replication fork to reorient the lagging-strand DNA polymerase so that it advances in parallel with the leading-strand polymerase. The replication loop grows and shrinks during each cycle of Okazaki fragment synthesis. The timing of Okazaki fragment synthesis and loop formation is determined by a subtle interplay of enzymatic activities at the fork. Recent developments in single-molecule techniques have enabled the direct observation of these processes and have greatly contributed to a better understanding of the dynamic nature of the replication fork. Here, we will review recent experimental advances, present the current models, and discuss some of the exciting developments in the field. 2010 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Environmental Assessment: Construct Mass/Mobility Parking Lot at Grand Forks AFB, North Dakota

    Science.gov (United States)

    2004-02-13

    land used for pasture and hay, urban development, recreation, and wildlife habitat. Principal crops are spring wheat , barley , sunflowers, potatoes...Dakota Aquifer has produced more water than any other aquifer in Grand Forks County, the water is very saline and generally unsatisfactory for domestic...flow periods, the rivers are generally too saline for domestic use. Grand Forks AFB receives water from Grand Forks and Lake Agassiz Water. The city

  7. Environmental Assessment: Construct New Pavilion Playground at Grand Forks AFB, North Dakota

    Science.gov (United States)

    2003-07-12

    pasture and hay, urban development, recreation, and wildlife habitat. Principal crops are spring wheat , barley , sunflowers, potatoes, and sugar...more water than any other aquifer in Grand Forks County, the water is very saline and generally unsatisfactory for domestic and most industrial uses...too saline for domestic use. Grand Forks AFB receives water from Grand Forks and Lake Agassiz Water. The city recovers its water from the Red River

  8. Environmental Assessment: Extend Parking Lot Building 807 at Grand Forks AFB, North Dakota

    Science.gov (United States)

    2003-07-17

    com, barley , and oats. The valley ranks first in the nation in the production of potatoes, spring wheat , sunflowers, and durum wheat . Grand Forks...crops are spring wheat , barley , sunflowers, potatoes, and sugar beets. Turtle River State Park, developed as a recreation area in Grand Forks County...surface. Even though the Dakota Aquifer has produced more water than any other aquifer in Grand Forks County, the water is very saline and

  9. Oriented Onion Sowing by a Forked-Roller Sowing Unit

    Directory of Open Access Journals (Sweden)

    Aleksandr G.

    2018-03-01

    Full Text Available Introduction: The existing sowing machines do not provide a single feeding of the bulbs with a planting (sowing unit that leads to a violation of the agrotechnical requirements of planting bulbs. It is necessary to search new solutions to preserve the position of the bulbs in the furrow with the bottom down and their regularly spaced distribution. Materials and Methods: The article presents the design for a prototype for a planting machine equipped with a forked-roller sowing unit for orienting the onion-sowing into a furrow. Testing the forked-roller sowing unit were carried out on a flat area where the physical and mechanical properties of the soil were determined on the days of sowing, and the indices of the quality of the onion-sowing were determined. The study of the effect of the sowing machine speed on the quality of the onion-seed bulb landing was determined by the change in the translational speed of the sowing unit in the range of 0.8 m/s to 1.2 m/s with a variation interval of 0.1 m/s. The indicators of the quality of the planting of the bulbs were determined by the opening of the closed furrow. The results of laboratory-field studies of the planting machine prototype are presented. Results: The results of laboratory-field studies of a planting machine equipped with a forked-roller sowing unit for planting onion bulbs are presented. The optimal technological parameters are determined experimentally. It was determined the number of bulbs that are for up is 51 % and the regularity of planting by the forked-roller sowing unit – 79 %. These figures are provided at the forward speed of the planting machine VM = 0.9–1.0 m/s, the height of the fall of the bulb HA = 0.12 m, and the rotation frequency of the landing drum nБ = 0.47 c-1. Discussion and Conclusions: The use of a forked-roller sowing unit makes it possible to increase the proportion of onions planted by bottom down by 200 %, and the uniformity of planting bulbs by 19 %, in

  10. Take It Slow: can feedback from a smart fork reduce eating speed?

    Directory of Open Access Journals (Sweden)

    Sander Hermsen

    2015-09-01

    The present study examines the efficacy of a smart fork that helps people to eat more slowly. This adapted fork records eating speed and delivers vibrotactile feedback if users eat too quickly. In two studies, we tested the acceptability and user experience of the fork (Study 1, and its effect on eating rate and satiety levels in a controlled lab-setting (Study 2. Method: In study 1, 11 participants (all self-reported fast eaters ate a meal using the fork in our laboratory and used the fork for three consecutive days in their home setting. Participants took part in semi-structured interviews after the first meal and upon returning the fork, covering perceived effect on eating rate, comfort of use, accuracy, and motivational and social aspects of fork use. Interviews were coded and a thematic classification analysis was performed. In study 2, 128 participants (all self-reported fast eaters ate a standardized meal using the fork in our laboratory. We used a between-participants design with 2 conditions; participants ate their meal either with vibrotactile feedback from the fork (experimental condition or ate their meal without vibrotactile feedback (control condition. Eating rate, meal duration, error rate (number of bites taken faster than 10 seconds after previous bite, total food intake, and satiety were recorded for every participant. Results: Study 1: All participants felt that the feedback was generally accurate and consistent. Fork size, weight, and intensity of the feedback were seen as comfortable and acceptable. All participants reported a heightened awareness of eating rate and all but one participant reported eating more slowly with the fork. Study 2: Participants in the experimental condition ate significantly slower, and with a lower error rate than those in the control condition. Feedback did not significantly affect the amount of food eaten. Conclusions: Our findings suggest that this smart fork is an acceptable and effective tool to disrupt and

  11. A Method to Predict Compressor Stall in the TF34-100 Turbofan Engine Utilizing Real-Time Performance Data

    Science.gov (United States)

    2015-06-01

    pass turbo –fan engine sensor data to seek its deterioration modelling and prognostics capability. In futurity this will allow for achievement of...preventive maintenance for the TF34-100 jet engine to prevent engine compressor stalls for the A-10 aircraft. Due to their destructive nature, compressor...stalls are a significant concern in axial flow compressor jet engines. A compressor stall is caused by air approaching the compressor blades at an

  12. An archival analysis of stall warning system effectiveness during airborne icing encounters

    Science.gov (United States)

    Maris, John Michael

    An archival study was conducted to determine the influence of stall warning system performance on aircrew decision-making outcomes during airborne icing encounters. A Conservative Icing Response Bias (CIRB) model was developed to explain the historical variability in aircrew performance in the face of airframe icing. The model combined Bayes' Theorem with Signal Detection Theory (SDT) concepts to yield testable predictions that were evaluated using a Binary Logistic Regression (BLR) multivariate technique applied to two archives: the NASA Aviation Safety Reporting System (ASRS) incident database, and the National Transportation Safety Board (NTSB) accident databases, both covering the period January 1, 1988 to October 2, 2015. The CIRB model predicted that aircrew would experience more incorrect response outcomes in the face of missed stall warnings than with stall warning False Alarms. These predicted outcomes were observed at high significance levels in the final sample of 132 NASA/NTSB cases. The CIRB model had high sensitivity and specificity, and explained 71.5% (Nagelkerke R2) of the variance of aircrew decision-making outcomes during the icing encounters. The reliability and validity metrics derived from this study suggest indicate that the findings are generalizable to the population of U.S. registered turbine-powered aircraft. These findings suggest that icing-related stall events could be reduced if the incidence of stall warning Misses could be minimized. Observed stall warning Misses stemmed from three principal causes: aerodynamic icing effects, which reduced the stall angle-of-attack (AoA) to below the stall warning calibration threshold; tail stalls, which are not monitored by contemporary protection systems; and icing-induced system issues (such as frozen pitot tubes), which compromised stall warning system effectiveness and airframe envelope protections. Each of these sources of missed stall warnings could be addressed by Aerodynamic Performance

  13. Stall Margin Improvement in a Centrifugal Compressor through Inducer Casing Treatment

    Directory of Open Access Journals (Sweden)

    V. V. N. K. Satish Koyyalamudi

    2016-01-01

    Full Text Available The increasing trend of high stage pressure ratio with increased aerodynamic loading has led to reduction in stable operating range of centrifugal compressors with stall and surge initiating at relatively higher mass flow rates. The casing treatment technique of stall control is found to be effective in axial compressors, but very limited research work is published on the application of this technique in centrifugal compressors. Present research was aimed to investigate the effect of casing treatment on the performance and stall margin of a high speed, 4 : 1 pressure ratio centrifugal compressor through numerical simulations using ANSYS CFX software. Three casing treatment configurations were developed and incorporated in the shroud over the inducer of the impeller. The predicted performance of baseline compressor (without casing treatment was in good agreement with published experimental data. The compressor with different inducer casing treatment geometries showed varying levels of stall margin improvement, up to a maximum of 18%. While the peak efficiency of the compressor with casing treatment dropped by 0.8%–1% compared to the baseline compressor, the choke mass flow rate was improved by 9.5%, thus enhancing the total stable operating range. The inlet configuration of the casing treatment was found to play an important role in stall margin improvement.

  14. An airloads theory for morphing airfoils in dynamic stall with experimental correlation

    Science.gov (United States)

    Ahaus, Loren A.

    Helicopter rotor blades frequently encounter dynamic stall during normal flight conditions, limiting the applicability of classical thin-airfoil theory at large angles of attack. Also, it is evident that because of the largely different conditions on the advancing and retreating sides of the rotor, future rotorcraft may incorporate dynamically morphing airfoils (trailing-edge aps, dynamic camber, dynamic droop, etc.). Reduced-order aerodynamic models are needed for preliminary design and ight simulation. A unified model for predicting the airloads on a morphing airfoil in dynamic stall is presented, consisting of three components. First, a linear airloads theory allows for arbitrary airfoil deformations consistent with a morphing airfoil. Second, to capture the effects of the wake, the airloads theory is coupled to an induced ow model. Third, the overshoot and time delay associated with dynamic stall are modeled by a second-order dynamic filter, along the lines of the ONERA dynamic stall model. This paper presents a unified airloads model that allows arbitrary airfoil morphing with dynamic stall. Correlations with experimental data validate the theory.

  15. A time-varying subjective quality model for mobile streaming videos with stalling events

    Science.gov (United States)

    Ghadiyaram, Deepti; Pan, Janice; Bovik, Alan C.

    2015-09-01

    Over-the-top mobile video streaming is invariably influenced by volatile network conditions which cause playback interruptions (stalling events), thereby impairing users' quality of experience (QoE). Developing models that can accurately predict users' QoE could enable the more efficient design of quality-control protocols for video streaming networks that reduce network operational costs while still delivering high-quality video content to the customers. Existing objective models that predict QoE are based on global video features, such as the number of stall events and their lengths, and are trained and validated on a small pool of ad hoc video datasets, most of which are not publicly available. The model we propose in this work goes beyond previous models as it also accounts for the fundamental effect that a viewer's recent level of satisfaction or dissatisfaction has on their overall viewing experience. In other words, the proposed model accounts for and adapts to the recency, or hysteresis effect caused by a stall event in addition to accounting for the lengths, frequency of occurrence, and the positions of stall events - factors that interact in a complex way to affect a user's QoE. On the recently introduced LIVE-Avvasi Mobile Video Database, which consists of 180 distorted videos of varied content that are afflicted solely with over 25 unique realistic stalling events, we trained and validated our model to accurately predict the QoE, attaining standout QoE prediction performance.

  16. Adsorption Thermodynamic Analysis of a Quartz Tuning Fork Based Sensor for Volatile Organic Compounds Detection.

    Science.gov (United States)

    Deng, Yue; Liu, Nai-Yuan; Tsow, Francis; Xian, Xiaojun; Forzani, Erica S

    2017-11-22

    A volatile organic compounds (VOC) sensor based on molecularly imprinted polymer (MIP) modified quartz tuning fork (QTF) has been developed. In this paper, the stability of the modified sensor as a function of the MIP composition, and the temperature effect of the analyte adsorption on the sensing transduction mechanism are evaluated. By mixing MIP and PS together, the stability was improved. A target analyte, o-xylene, was chosen as the VOC model to study the sensor response in a temperature range of 6-40 °C. Langmuir model fitted adsorption isotherms were used for thermodynamic analysis. The changes in the sensitivity of the QTF sensor to temperature rendered different behaviors. For a freshly modified QTF sensor, the adsorption response increased with increasing temperature, while for an aged QTF sensor, the adsorption response decreased with increasing temperature. The results indicated that the enthalpy change of the MIP and PS composition sensing material changes from positive to negative over the course of aging. The characterization of the reaction enabled the definition of sensor calibration conditions and stable sensor performance in field testing conditions.

  17. Design of a Tuning Fork type UWB Patch Antenna

    OpenAIRE

    A. H. M. Zahirul Alam; Rafiqul Islam; Sheroz Khan

    2007-01-01

    In this paper a tuning fork type structure of Ultra Wideband (UWB) antenna is proposed. The antenna offers excellent performance for UWB system, ranging from 3.7 GHz to 13.8 GHz. The antenna exhibits a 10 dB return loss bandwidth over the entire frequency band. The rectangular patch antenna is designed on FR4 substrate and fed with 50 ohms microstrip line by optimizing the width of partial ground, the width and position of the feedline to operate in UWB. The rectangular p...

  18. Burnup measurements with the Los Alamos fork detector

    International Nuclear Information System (INIS)

    Bosler, G.E.; Rinard, P.M.

    1991-01-01

    The fork detector system can determine the burnup of spent-fuel assemblies. It is a transportable instrument that can be mounted permanently in a spent-fuel pond near a loading area for shipping casks, or be attached to the storage pond bridge for measurements on partially raised spent-fuel assemblies. The accuracy of the predicted burnup has been demonstrated to be as good as 2% from measurements on assemblies in the United States and other countries. Instruments have also been developed at other facilities throughout the world using the same or different techniques, but with similar accuracies. 14 refs., 2 figs., 2 tabs

  19. The role of tip clearance in high-speed fan stall

    Energy Technology Data Exchange (ETDEWEB)

    Adamczyk, J.J. (NASA Lewis Research Center, Cleveland, OH (United States)); Celestina, M.L. (Sverdrup Tech., Inc., Cleveland, OH (United States)); Greitzer, E.M. (Massachusetts Institute of Technology, Cambridge, MA (United States))

    1993-01-01

    A numerical experiment has been carried out to define the near-stall casing endwall flow field of a high-speed fan rotor. The experiment used a simulation code incorporating a simple clearance model, whose calibration is presented. The results of the simulation show that the interaction of the tip leakage vortex and the in-passage shock plays a major role in determining the fan flow range. More specifically, the computations imply that it is the area increase of this vortex as it passes through the in-passage shock that is the source of the blockage associated with stall. In addition, for fans of this type, it is the clearance over the forward portion of the fan blade that controls the flow processes leading to stall.

  20. The role of tip clearance in high-speed fan stall

    Science.gov (United States)

    Adamczyk, J. J.; Celestina, M. L.; Greitzer, E. M.

    1991-01-01

    A numerical experiment has been carried out to define the near-stall casing endwall flowfield of a high-speed fan rotor. The experiment used a simulation code incorporating a simple clearance model, whose calibration is presented. The results of the simulation show that the interaction of the tip leakage vortex and the in-pasage shock plays a major role in determining the fan flow range. More specifically, the computations imply that it is the area increase of this vortex as it passes through the in-passage shock, which is the source of the blockage associated with stall. In addition, for fans of this type, it is the clearance over the forward portion of the fan blade which controls the flow processes leading to stall.

  1. The computation of the post-stall behavior of a circulation controlled airfoil

    Science.gov (United States)

    Linton, Samuel W.

    1993-01-01

    The physics of the circulation controlled airfoil is complex and poorly understood, particularly with regards to jet stall, which is the eventual breakdown of lift augmentation by the jet at some sufficiently high blowing rate. The present paper describes the numerical simulation of stalled and unstalled flows over a two-dimensional circulation controlled airfoil using a fully implicit Navier-Stokes code, and the comparison with experimental results. Mach numbers of 0.3 and 0.5 and jet total to freestream pressure ratios of 1.4 and 1.8 are investigated. The Baldwin-Lomax and k-epsilon turbulence models are used, each modified to include the effect of strong streamline curvature. The numerical solutions of the post-stall circulation controlled airfoil show a highly regular unsteady periodic flowfield. This is the result of an alternation between adverse pressure gradient and shock induced separation of the boundary layer on the airfoil trailing edge.

  2. A watershed's response to logging and roads: South Fork of Caspar Creek, California, 1967-1976

    Science.gov (United States)

    Raymond M. Rice; Forest B. Tilley; Patricia A. Datzman

    1979-01-01

    The effect of logging and roadbuilding on erosion and sedimentation are analyzed by comparing the North Fork and South Fork of Caspar Creek, in northern California. Increased sediment production during the 4 years after road construction, was 326 cu yd/sq mi/yr—80 percent greater than that predicted by the predisturbance regression analysis. The average...

  3. Effect of summer grazing on welfare of dairy cows reared in mountain tie-stall barns

    Directory of Open Access Journals (Sweden)

    Simonetta Dovier

    2010-09-01

    Full Text Available Traditional mountain farms have an important economic, social and environmental role. The Alps management system for dairy cows consists of animals kept indoors from autumn to spring, mostly in tie-stalls, and moved to mountain pasture in summer. The aim of our study was to assess the effect of mountain summer grazing on the welfare of dairy cows housed in tie-stall barns. Twenty-four farms were considered. In twelve of them, animals were reared in tie-stalls and moved to mountain pasture for three months in summer; they were visited three times: (i four weeks before grazing during the indoor period in the stall; (ii about three weeks after the start of grazing; and (iii in the stall, in autumn, at least three weeks after returning from grazing. The other twelve farms kept the animals in tie-stalls all year; they were visited once in autumn. Data were collected following a protocol that considers animal-based measures and structure information on the basis of Quality Welfare Consortium® indications. Data allowed the calculation of both the Animal Needs Index score (ANI 35L and an overall assessment of the cows’ welfare obtained from three general aspects: housing, animal’s physical condition, and animal’s behaviour. Summer grazing had a significant positive effect on injuries, lameness and animal’s rising duration but a negative effect on faeces consistency. Moreover, a reduction of tongue playing was observed. The ANI 35L and the overall assessment did not show significant differences linked to summer grazing, which tended to have a positive but temporary effect on animal behaviour.

  4. Improve performance of scanning probe microscopy by balancing tuning fork prongs

    International Nuclear Information System (INIS)

    Ng, Boon Ping; Zhang Ying; Wei Kok, Shaw; Chai Soh, Yeng

    2009-01-01

    This paper presents an approach for improving the Q-factor of tuning fork probe used in scanning probe microscopes. The improvement is achieved by balancing the fork prongs with extra mass attachment. An analytical model is proposed to characterize the Q-factor of a tuning fork probe with respect to the attachment of extra mass on the tuning fork prongs, and based on the model, the Q-factors of the unbalanced and balanced tuning fork probes are derived and compared. Experimental results showed that the model fits well the experimental data and the approach can improve the Q-factor by more than a factor of three. The effectiveness of the approach is further demonstrated by applying the balanced probe on an atomic force microscope to obtain improved topographic images.

  5. Prediction of RNA Polymerase II recruitment, elongation and stalling from histone modification data

    DEFF Research Database (Denmark)

    Chen, Yun; Jørgensen, Mette; Kolde, Raivo

    2011-01-01

    strategies are needed to progress from descriptive annotation of data to quantitative, predictive models. RESULTS: Here, we describe a computational framework which with high accuracy can predict the locations of core promoters, the amount of recruited RNAPII at the promoter, the amount of elongating RNAPII...... of RNAPII stalling. CONCLUSIONS: In this study we introduce a general framework to accurately predict the level of RNAPII recruitment, elongation, stalling and mRNA expression from chromatin signals. The versatility of the method also makes it ideally suited to investigate other genomic data....

  6. Analysis of compressible light dynamic stall flow at transitional Reynolds numbers

    DEFF Research Database (Denmark)

    Dyken, R.D. Van; Ekaterinaris, John A.; Chandrasekhara, M.S.

    1996-01-01

    Numerical and experimental results of steady and light dynamic stall flow over an oscillating NACA 0012 airfoil at a freestream Mach number of 0.3 and Reynolds number of 0.54 x 10(6) are compared, The experimental observation that dynamic stall is induced from the bursting of a laminar separation...... point is specified suitably and a simple transition length model is incorporated to determine the extent of the laminar separation bubble. The thin-layer approximations of compressible, Reynolds-averaged, Navier-Stokes equations are used for the numerical solution, with an implicit, upwind-biased, third...

  7. The influence of elevated feed stalls on feeding behaviour of lactating dairy cows

    Directory of Open Access Journals (Sweden)

    Barbara Benz

    2014-10-01

    Full Text Available The performance level of high yielding cows can only be guaranteed by high quality forage and high feed intake. An about 15–20 cm elevated and 160 cm long feed stall with rubber flooring doesn’t only offer undisturbed meals but also a yielding and dry standing surface. In a pilot stable with 130 dairy cows (German Simmental the feeding alley was subsequently equipped with elevated feed stalls. The results show that animals frequented the feeding barn less often while the duration of single meals prolonged. The specific behavioural changes differed depending on milk yield and number of lactation.

  8. Diagnosis of voltage collapse due to induction motor stalling using static analysis

    International Nuclear Information System (INIS)

    Karbalaei, F.; Kalantar, M.; Kazemi, A.

    2008-01-01

    Induction motor stalling is one of the important reasons for voltage collapse. This paper presents that, for induction motor stalling diagnosis, it is not necessary to use a third or first order dynamic model of induction motors. Instead, a method is presented based on algebraic calculations for which the steady state model of the induction motor considering different kinds of mechanical loads (constant and variable torque) is added to the power flow equations. Simulation results for a simple system confirm the correctness of the proposed method as compared to dynamic simulation results

  9. Power control of a wind farm with active stall wind turbines and AC grid connection

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Sørensen, Poul; Iov, Florin

    This paper describes the design of a centralised wind farm controller for a wind farm made-up exclusively of active stall wind turbines with AC grid connection. The overall aim of such controller is to enable the wind farms to provide the best grid support. The designed wind farm control involves...... both the control on wind turbine level as well as the central control on the wind farm level. The ability of active stall wind farms with AC grid connection to regulate the power production to the reference power ordered by the operators is assessed and discussed by means of simulations....

  10. Validation of the Beddoes-Leishman Dynamic Stall Model for Horizontal Axis Wind Turbines using MEXICO data

    NARCIS (Netherlands)

    Pereira, R.; Schepers, G.; Pavel, M.D.

    2011-01-01

    The aim of this study is to assess the load predicting capability of a classical Beddoes-Leishman dynamic stall model in a horizontal axis wind turbine (HAWT) environment, in the presence of yaw-misalignment. The dynamic stall model was tailored to the HAWT environment, and validated against

  11. Building up and breaking down: mechanisms controlling recombination during replication.

    Science.gov (United States)

    Branzei, Dana; Szakal, Barnabas

    2017-08-01

    The complete and faithful duplication of the genome is an essential prerequisite for proliferating cells to maintain genome integrity. This objective is greatly challenged by DNA damage encountered during replication, which causes fork stalling and in certain cases, fork breakage. DNA damage tolerance (DDT) pathways mitigate the effects on fork stability induced by replication fork stalling by mediating damage-bypass and replication fork restart. These DDT mechanisms, largely relying on homologous recombination (HR) and specialized polymerases, can however contribute to genome rearrangements and mutagenesis. There is a profound connection between replication and recombination: recombination proteins protect replication forks from nuclease-mediated degradation of the nascent DNA strands and facilitate replication completion in cells challenged by DNA damage. Moreover, in case of fork collapse and formation of double strand breaks (DSBs), the recombination factors present or recruited to the fork facilitate HR-mediated DSB repair, which is primarily error-free. Disruption of HR is inexorably linked to genome instability, but the premature activation of HR during replication often leads to genome rearrangements. Faithful replication necessitates the downregulation of HR and disruption of active RAD51 filaments at replication forks, but upon persistent fork stalling, building up of HR is critical for the reorganization of the replication fork and for filling-in of the gaps associated with discontinuous replication induced by DNA lesions. Here we summarize and reflect on our understanding of the mechanisms that either suppress recombination or locally enhance it during replication, and the principles that underlie this regulation.

  12. A stochastic model for the simulation of wind turbine blades in static stall

    DEFF Research Database (Denmark)

    Bertagnolio, Franck; Rasmussen, Flemming; Sørensen, Niels N.

    2010-01-01

    The aim of this work is to improve aeroelastic simulation codes by accounting for the unsteady aerodynamic forces that a blade experiences in static stall. A model based on a spectral representation of the aerodynamic lift force is defined. The drag and pitching moment are derived using...

  13. Physics of Prestall Propagating Disturbances in Axial Compressors and Their Potential as a Stall Warning Indicator

    Directory of Open Access Journals (Sweden)

    Mario Eck

    2017-03-01

    Full Text Available Axial compressors in aero engines are prone to suffering a breakdown of orderly flow when operating at the peak of the pressure rise characteristic. The damaging potential of separated flows is why a safe distance has to be left between every possible operating point and an operating point at which stall occurs. During earlier investigations of stall inception mechanisms, a new type of prestall instability has been found. In this study, it could be demonstrated that the prestall instability characterised by discrete flow disturbances can be clearly assigned to the subject of “Rotating Instabilities”. Propagating disturbances are responsible for the rise in blade passing irregularity. If the mass flow is reduced successively, the level of irregularity increases until the prestall condition devolves into rotating stall. The primary objective of the current work is to highlight the basic physics behind these prestall disturbances by complementary experimental and numerical investigations. Before reaching the peak of the pressure rise characteristic flow, disturbances appear as small vortex tubes with one end attached to the casing and the other attached to the suction surface of the rotor blade. These vortex structures arise when the entire tip region is affected by blockage and at the same time the critical rotor incidence is not exceeded in this flow regime. Furthermore, a new stall indicator was developed by applying statistical methods to the unsteady pressure signal measured over the rotor blade tips, thus granting a better control of the safety margin.

  14. Numerical Study on the Acoustic Characteristics of an Axial Fan under Rotating Stall Condition

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2017-11-01

    Full Text Available Axial fan is an important piece of equipment in the thermal power plant that provides enough air for combustion of coal. This paper focuses on the aerodynamic noise characteristics of an axial fan in the development from stall inception to stall cells. The aerodynamic noise characteristic of monitoring region in time and frequency domains was simulated employing the large-eddy simulation (LES, with the addition of throttle setting and the Ffowcs Williams-Hawkings (FW-H noise model. The numerical results show that, under the design condition, the acoustic pressure presents regular periodicity along with the time. The noise energy is concentrated with high energy of the fundamental frequency and high order harmonics. During the stall inception stage, the acoustic pressure amplitude starts fluctuating and discrete frequencies are increased significantly in the low frequency; among them, there are three obvious discrete frequencies: 27.66 Hz, 46.10 Hz and 64.55 Hz. On the rotating stall condition, the fluctuation of the acoustic pressure level and amplitude are more serious than that mentioned above. During the whole evolution process, the acoustic pressure peak is difficult to keep stable all the time, and a sudden increase of the peak value at the 34.5th revolution corresponds to the relative velocity’s first sudden increase at the time when the valve coefficient is 0.780.

  15. Accounting for biases in riboprofiling data indicates a major role for proline in stalling translation.

    Science.gov (United States)

    Artieri, Carlo G; Fraser, Hunter B

    2014-12-01

    The recent advent of ribosome profiling-sequencing of short ribosome-bound fragments of mRNA-has offered an unprecedented opportunity to interrogate the sequence features responsible for modulating translational rates. Nevertheless, numerous analyses of the first riboprofiling data set have produced equivocal and often incompatible results. Here we analyze three independent yeast riboprofiling data sets, including two with much higher coverage than previously available, and find that all three show substantial technical sequence biases that confound interpretations of ribosomal occupancy. After accounting for these biases, we find no effect of previously implicated factors on ribosomal pausing. Rather, we find that incorporation of proline, whose unique side-chain stalls peptide synthesis in vitro, also slows the ribosome in vivo. We also reanalyze a method that implicated positively charged amino acids as the major determinant of ribosomal stalling and demonstrate that it produces false signals of stalling in low-coverage data. Our results suggest that any analysis of riboprofiling data should account for sequencing biases and sparse coverage. To this end, we establish a robust methodology that enables analysis of ribosome profiling data without prior assumptions regarding which positions spanned by the ribosome cause stalling. © 2014 Artieri and Fraser; Published by Cold Spring Harbor Laboratory Press.

  16. EVALUATION OF STYRENE EMISSIONS FROM A SHOWER STALL/BATHTUB MANUFACTURING FACILITY

    Science.gov (United States)

    The report gives results of emissions measurements carried out at a representative facility (Eljer Plumbingware in Wilson, NC) that manufactures polyester-resin-reinforced shower stalls and bathtubs by spraying styrene-based resins onto molds in vented, open, spray booths. Styren...

  17. 14 CFR 23.203 - Turning flight and accelerated turning stalls.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turning flight and accelerated turning stalls. 23.203 Section 23.203 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... a 30 degree bank. Reduce speed by steadily and progressively tightening the turn with the elevator...

  18. Power reduction and the radial limit of stall delay in revolving wings of different aspect ratio

    NARCIS (Netherlands)

    Kruyt, J.W.; Heijst, Van G.F.; Altshuler, D.L.; Lentink, David

    2015-01-01

    Airplanes and helicopters use high aspect ratio wings to reduce the power required to fly, but must operate at low angle of attack to prevent flow separation and stall. Animals capable of slow sustained flight, such as hummingbirds, have low aspect ratio wings and flap their wings at high angle

  19. Vortical structures responsible for delayed stall in an idealized humpback whale flipper model

    Science.gov (United States)

    Kim, Heesu; Kim, Jooha; Choi, Haecheon

    2016-11-01

    In this study, we investigate how the tubercles on the leading edge of an idealized humpback whale flipper model delay the stall. Oil-surface visualization is performed to see the surface flow pattern on the suction surface, and PIV is conducted in several streamwise and crossflow planes at different attack angles (α). Without tubercles, leading edge separation first occurs near the tip region and progresses inboard with increasing α. With tubercles, however, two types of vortical motions are observed at the mid-span. The first is streamwise vortex arrays which are dominant at α 9° , and these structures appear near the trailing edge. These two types of vortical motions delay flow separation at the peak regions of the mid-span, eliminating the spanwise stall progression and resulting in delayed stall. At α = 16° at which the tubercle model stalls, a large-scale streamwise vortex is originated from flow separation near the root region. This structure delays flow separation at the mid-span, leading to higher lift coefficient. Supported by NRF-2014M3C1B1033848.

  20. Theory/test correlation of helicopter rotor blade element airloads in the blade stall regime

    Science.gov (United States)

    Bobo, C. J.

    1972-01-01

    The effects of stall on a rotor blade element in a three-dimensional rotating environment was investigated. The model rotor test provided blade element airloads and local boundary layer flow characteristics at the three-quarter blade radius position for a wide range of rotor operating conditions. A description of the test program and the test results are presented.

  1. Field rotor measurements. Data sets prepared for analysis of stall hysteresis

    Energy Technology Data Exchange (ETDEWEB)

    Aagaard Madsen, H.; Thirstrup Petersen, J. [Risoe National Lab. (Denmark); Bruining, A. [Delft Univ. of Technology (Netherlands); Brand, A. [ECN (Netherlands); Graham, M. [Imperical College (United Kingdom)

    1998-05-01

    As part of the JOULE-3 project `STALLVIB` an analysis and synthesis of the data from the field rotor experiments at ECN, Delft University, Imperial College, NREL and Risoe has been carried out. This has been done in order to see to what extent the data could be used for further development and validation of engineering dynamic stall models. A detailed investigation of the influence of the post-processing of the different data sets has been performed. Further, important statistical functions such as PSD spectra, coherence and transfer functions have been derived for the data sets which can be used as basis for evaluation of the quality of the data seen relative to actual application of the data. The importance of using an appropriate low-pass filtering to remove high frequency noise has been demonstrated when the relation between instantaneous values of e.g. {alpha} and C{sub N} is considered. In general, the complicated measurement on a rotor of {alpha} and w and the interpretation of these parameters combined with the strongly three-dimensional, turbulent flow field around the rotating blade has the consequence that it seems difficult to derive systematic information from the different data sets about stall hysteresis. In particular, the measurement of {alpha}, which determination of the stagnation point gives reasonable data below stall but fails in stall. On the other hand, measurements of {alpha} with a five hole pitot tube can be used also in the stall region. Another main problem is the non-dimensionalization of the coefficients C{sub N} and C{sub r}. If the dynamic pressure used for the non-dimensionalization is not fully correlated with the aerodynamic pressure over the considered airfoil section due to e.g. influence of the gravity on the pressure pipes, the hysteresis loops will be distorted. However, using the data with caution and applying a suitable post-processing as described by the different participants, it will probably be possible to obtain some

  2. Modeling dynamic stall on wind turbine blades under rotationally augmented flow fields

    Energy Technology Data Exchange (ETDEWEB)

    Guntur, S. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Schreck, S. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sorensen, N. N. [Technical Univ. of Denmark, Lyngby (Denmark); Bergami, L. [Technical Univ. of Denmark, Lyngby (Denmark)

    2015-04-22

    It is well known that airfoils under unsteady flow conditions with a periodically varying angle of attack exhibit aerodynamic characteristics different from those under steady flow conditions, a phenomenon commonly known as dynamic stall. It is also well known that the steady aerodynamic characteristics of airfoils in the inboard region of a rotating blade differ from those under steady two-dimensional (2D) flow conditions, a phenomenon commonly known as rotational augmentation. This paper presents an investigation of these two phenomena together in the inboard parts of wind turbine blades. This analysis is carried out using data from three sources: (1) the National Renewable Energy Laboratory’s Unsteady Aerodynamics Experiment Phase VI experimental data, including constant as well as continuously pitching blade conditions during axial operation, (2) data from unsteady Delayed Detached Eddy Simulations (DDES) carried out using the Technical University of Denmark’s in-house flow solver Ellipsys3D, and (3) data from a simplified model based on the blade element momentum method with a dynamic stall subroutine that uses rotationally augmented steady-state polars obtained from steady Phase VI experimental sequences, instead of the traditional 2D nonrotating data. The aim of this work is twofold. First, the blade loads estimated by the DDES simulations are compared to three select cases of the N sequence experimental data, which serves as a validation of the DDES method. Results show reasonable agreement between the two data in two out of three cases studied. Second, the dynamic time series of the lift and the moment polars obtained from the experiments are compared to those from the dynamic stall subroutine that uses the rotationally augmented steady polars. This allowed the differences between the stall phenomenon on the inboard parts of harmonically pitching blades on a rotating wind turbine and the classic dynamic stall representation in 2D flow to be

  3. Parametric analyses on dynamic stall control of rotor airfoil via synthetic jet

    Directory of Open Access Journals (Sweden)

    Qijun ZHAO

    2017-12-01

    Full Text Available The effects of synthetic jet control on unsteady dynamic stall over rotor airfoil are investigated numerically. A moving-embedded grid method and an Unsteady Reynolds Averaged Navier-Stokes (URANS solver coupled with k-ω Shear Stress Transport (SST turbulence model are established for predicting the complex flowfields of oscillatory airfoil under jet control. Additionally, a velocity boundary condition modeled by sinusoidal function has been developed to fulfill the perturbation effect of periodic jet. The validity of present CFD method is evaluated by comparisons of the calculated results of baseline dynamic stall case for rotor airfoil and jet control case for VR-7B airfoil with experimental data. Then, parametric analyses are conducted emphatically for an OA212 rotor airfoil to investigate the effects of jet control parameters (jet location, dimensionless frequency, momentum coefficient, jet angle, jet type and dual-jet on dynamic stall characteristics of rotor airfoil. It is demonstrated by the calculated results that efficiency of jet control could be improved with specific momentum coefficient and jet angle when the jet is located near separation point of rotor airfoil. Furthermore, the dual-jet could improve control efficiency more obviously on dynamic stall of rotor airfoil with respect to the unique jet, and the influence laws of dual-jet’s angles and momentum coefficients on control effects are similar to those of the unique jet. Finally, unsteady aerodynamic characteristics of rotor via synthetic jet which is located on the upper surface of rotor blade in forward flight are calculated, and as a result, the aerodynamic characteristics of rotor are improved compared with the baseline. The results indicate that synthetic jet has the capability in improving aerodynamic characteristics of rotor. Keywords: Airfoil, Dynamic stall characteristics, Flow control, Moving-embedded grid methodology, Navier-Stokes equations, Parametric

  4. Power reduction and the radial limit of stall delay in revolving wings of different aspect ratio.

    Science.gov (United States)

    Kruyt, Jan W; van Heijst, GertJan F; Altshuler, Douglas L; Lentink, David

    2015-04-06

    Airplanes and helicopters use high aspect ratio wings to reduce the power required to fly, but must operate at low angle of attack to prevent flow separation and stall. Animals capable of slow sustained flight, such as hummingbirds, have low aspect ratio wings and flap their wings at high angle of attack without stalling. Instead, they generate an attached vortex along the leading edge of the wing that elevates lift. Previous studies have demonstrated that this vortex and high lift can be reproduced by revolving the animal wing at the same angle of attack. How do flapping and revolving animal wings delay stall and reduce power? It has been hypothesized that stall delay derives from having a short radial distance between the shoulder joint and wing tip, measured in chord lengths. This non-dimensional measure of wing length represents the relative magnitude of inertial forces versus rotational accelerations operating in the boundary layer of revolving and flapping wings. Here we show for a suite of aspect ratios, which represent both animal and aircraft wings, that the attachment of the leading edge vortex on a revolving wing is determined by wing aspect ratio, defined with respect to the centre of revolution. At high angle of attack, the vortex remains attached when the local radius is shorter than four chord lengths and separates outboard on higher aspect ratio wings. This radial stall limit explains why revolving high aspect ratio wings (of helicopters) require less power compared with low aspect ratio wings (of hummingbirds) at low angle of attack and vice versa at high angle of attack. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  5. The ribosome quality control pathway can access nascent polypeptides stalled at the Sec61 translocon.

    Science.gov (United States)

    von der Malsburg, Karina; Shao, Sichen; Hegde, Ramanujan S

    2015-06-15

    Cytosolic ribosomes that stall during translation are split into subunits, and nascent polypeptides trapped in the 60S subunit are ubiquitinated by the ribosome quality control (RQC) pathway. Whether the RQC pathway can also target stalls during cotranslational translocation into the ER is not known. Here we report that listerin and NEMF, core RQC components, are bound to translocon-engaged 60S subunits on native ER membranes. RQC recruitment to the ER in cultured cells is stimulated by translation stalling. Biochemical analyses demonstrated that translocon-targeted nascent polypeptides that subsequently stall are polyubiquitinated in 60S complexes. Ubiquitination at the translocon requires cytosolic exposure of the polypeptide at the ribosome-Sec61 junction. This exposure can result from either failed insertion into the Sec61 channel or partial backsliding of translocating nascent chains. Only Sec61-engaged nascent chains early in their biogenesis were relatively refractory to ubiquitination. Modeling based on recent 60S-RQC and 80S-Sec61 structures suggests that the E3 ligase listerin accesses nascent polypeptides via a gap in the ribosome-translocon junction near the Sec61 lateral gate. Thus the RQC pathway can target stalled translocation intermediates for degradation from the Sec61 channel. © 2015 von der Malsburg et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  6. Experimental and numerical investigation on the motorcycle front frame flexibility and its effect on stability

    Science.gov (United States)

    Cossalter, V.; Doria, A.; Massaro, M.; Taraborrelli, L.

    2015-08-01

    It is well known that front fork flexibility may have a significant effect on motorcycle stability. This work addresses the problem of developing lumped element models of the front fork from experimental results. The front forks of an enduro motorcycle and of a super sport motorcycle are characterized performing static, dynamic and modal tests by means of specific testing equipment. The concept of wheel twisting axis is proposed to characterize static and dynamic deformability of the front fork. Modal analysis results show the presence of two important modes of vibration of the front assembly in the low frequency range: the lateral mode and the longitudinal mode. Different lumped models are discussed and a new model that takes into account information obtained from static and dynamic tests is proposed. Simulations are carried out by means of a multibody code and show the effect of the front assembly deformability on the weave and wobble vibration modes.

  7. Oxbow Conservation Area; Middle Fork John Day River, Annual Report 2003-2004.

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, Brian

    2004-02-01

    In early 2001, the Confederated Tribes of Warm Springs, through their John Day Basin Office, concluded the acquisition of the Oxbow Ranch, now know as the Oxbow Conservation Area (OCA). Under a memorandum of agreement with the Bonneville Power Administration (BPA), the Tribes are required to provided BPA an 'annual written report generally describing the real property interests in the Project, HEP analyses undertaken or in progress, and management activities undertaken or in progress'. The project during 2003 was crippled due to the aftermath of the BPA budget crisis. Some objectives were not completed during the first half of this contract because of limited funds in the 2003 fiscal year. The success of this property purchase can be seen on a daily basis. Water rights were utilized only in the early, high water season and only from diversion points with functional fish screens. After July 1, all of the OCA water rights were put instream. Riparian fences on the river, Ruby and Granite Boulder creeks continued to promote important vegetation to provide shade and bank stabilization. Hundreds of willow, dogwood, Douglas-fir, and cottonwood were planted along the Middle Fork John Day River. Livestock grazing on the property was carefully managed to ensure the protection of fish and wildlife habitat, while promoting meadow vigor and producing revenue for property taxes. Monitoring of property populations, resources, and management activities continued in 2003 to build a database for future management of this and other properties in the region.

  8. Structure design of AlN double-ended tuning fork resonators

    Science.gov (United States)

    Lei, Qiang; Gao, Yang; Han, Chao

    2017-11-01

    The resonant sensors based on aluminum nitride double-ended tuning fork (AlN DETF) have the characteristics of small size, good stability and reliability, fast response. In order to improve the sensitivity and resolution, it is necessary to analyze the influence of the structure parameters of vibrating beam on the sensitivity and signal power of AlN resonator. The multi-physics model of AlN DETF resonator was established to verify effect of single parameter on the sensitivity by pre-stressed eigenfrequency analysis. The relationships between signal power and length, width of vibrating beam were obtained by post-processing data of simulation results when the thickness remained constant. The results show that relative sensitivity and signal power are growing with opposite direction with the width or the length of the beam. Therefore, there is a design tradeoff between signal power and relative sensitivity of AlN resonator according to the process and structure strength. The optimized AlN DETF resonator was simulated, its sensitivity, signal power and Q are 56 Hz/μN, 6.8e-4 nW and 958, respectively.

  9. The analyst's body as tuning fork: embodied resonance in countertransference.

    Science.gov (United States)

    Stone, Martin

    2006-02-01

    This paper examines the phenomenon of embodied countertransference: where the analyst experiences a somatic reaction rather than the more common countertransference responses of thoughts, feelings, images, fantasies and dreams. Discussion of clinical material considers neurotic and syntonic aspects. The analogy is made of resonance with a tuning fork. Several questions are posed: Why does countertransference resonate in the bodies of some analysts but not all? Why do those analysts who are sensitive to this, experience it with some patients but not with others? And what are the conditions which are conducive to producing somatic responses? It proposes that somatic reactions are more likely to occur when a number of conditions come together: when working with patients exhibiting borderline, psychotic or severe narcissistic elements; where there has been early severe childhood trauma; and where there is fear of expressing strong emotions directly. In addition another theoretical factor is proposed, namely the typology of the analyst.

  10. Finite Element Analysis of Electrically Excited Quartz Tuning Fork Devices

    Science.gov (United States)

    Oria, Roger; Otero, Jorge; González, Laura; Botaya, Luis; Carmona, Manuel; Puig-Vidal, Manel

    2013-01-01

    Quartz Tuning Fork (QTF)-based Scanning Probe Microscopy (SPM) is an important field of research. A suitable model for the QTF is important to obtain quantitative measurements with these devices. Analytical models have the limitation of being based on the double cantilever configuration. In this paper, we present an electromechanical finite element model of the QTF electrically excited with two free prongs. The model goes beyond the state-of-the-art of numerical simulations currently found in the literature for this QTF configuration. We present the first numerical analysis of both the electrical and mechanical behavior of QTF devices. Experimental measurements obtained with 10 units of the same model of QTF validate the finite element model with a good agreement. PMID:23722828

  11. Finite Element Analysis of Electrically Excited Quartz Tuning Fork Devices

    Directory of Open Access Journals (Sweden)

    Manel Puig-Vidal

    2013-05-01

    Full Text Available Quartz Tuning Fork (QTF-based Scanning Probe Microscopy (SPM is an important field of research. A suitable model for the QTF is important to obtain quantitative measurements with these devices. Analytical models have the limitation of being based on the double cantilever configuration. In this paper, we present an electromechanical finite element model of the QTF electrically excited with two free prongs. The model goes beyond the state-of-the-art of numerical simulations currently found in the literature for this QTF configuration. We present the first numerical analysis of both the electrical and mechanical behavior of QTF devices. Experimental measurements obtained with 10 units of the same model of QTF validate the finite element model with a good agreement.

  12. Internal Flow of a High Specific-Speed Diagonal-Flow Fan (Rotor Outlet Flow Fields with Rotating Stall

    Directory of Open Access Journals (Sweden)

    Norimasa Shiomi

    2003-01-01

    Full Text Available We carried out investigations for the purpose of clarifying the rotor outlet flow fields with rotating stall cell in a diagonal-flow fan. The test fan was a high–specific-speed (ns=1620 type of diagonal-flow fan that had 6 rotor blades and 11 stator blades. It has been shown that the number of the stall cell is 1, and its propagating speed is approximately 80% of its rotor speed, although little has been known about the behavior of the stall cell because a flow field with a rotating stall cell is essentially unsteady. In order to capture the behavior of the stall cell at the rotor outlet flow fields, hot-wire surveys were performed using a single-slant hotwire probe. The data obtained by these surveys were processed by means of a double phase-locked averaging technique, which enabled us to capture the flow field with the rotating stall cell in the reference coordinate system fixed to the rotor. As a result, time-dependent ensemble averages of the three-dimensional velocity components at the rotor outlet flow fields were obtained. The behavior of the stall cell was shown for each velocity component, and the flow patterns on the meridional planes were illustrated.

  13. Theoretical model and optimization of a novel temperature sensor based on quartz tuning fork resonators

    International Nuclear Information System (INIS)

    Xu Jun; You Bo; Li Xin; Cui Juan

    2007-01-01

    To accurately measure temperatures, a novel temperature sensor based on a quartz tuning fork resonator has been designed. The principle of the quartz tuning fork temperature sensor is that the resonant frequency of the quartz resonator changes with the variation in temperature. This type of tuning fork resonator has been designed with a new doubly rotated cut work at flexural vibration mode as temperature sensor. The characteristics of the temperature sensor were evaluated and the results sufficiently met the target of development for temperature sensor. The theoretical model for temperature sensing has been developed and built. The sensor structure was analysed by finite element method (FEM) and optimized, including tuning fork geometry, tine electrode pattern and the sensor's elements size. The performance curve of output versus measured temperature is given. The results from theoretical analysis and experiments indicate that the sensor's sensitivity can reach 60 ppm 0 C -1 with the measured temperature range varying from 0 to 100 0 C

  14. Environmental Assessment: Demolish CASS Switch Stations Buildings 644, 645, 646 at Grand Forks Air Force Base

    Science.gov (United States)

    2006-06-01

    barley , and oats. The valley ranks first in the nation in the production of potatoes, spring wheat , sunflowers, and durum wheat . Grand Forks...remaining land used for pasture and hay, urban development, recreation, and wildlife habitat. Principal crops are spring wheat , barley , sunflowers...though the Dakota Aquifer has produced more water than any other aquifer in Grand Forks County, the water is very saline and generally unsatisfactory

  15. The Sound Field around a Tuning Fork and the Role of a Resonance Box

    Science.gov (United States)

    Bogacz, Bogdan F.; Pedziwiatr, Antoni T.

    2015-01-01

    Atypical two-tine tuning fork is barely audible when held vibrating at an arm's length. It is enough, however, to touch its base to a table or, better, to a resonance box and the emitted sound becomes much louder. An inquiring student may pose questions: (1) Why is a bare tuning fork such a weak emitter of sound? (2) What is the role of the…

  16. Investigation of the wind climate in connection with double-stall on wind turbines in Tarifa[Spain]; Undersoegelse af vindklima i forbindelse med dobbelt-stall paa vindmoeller i Tarifa

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, T. [ELSAMPROJEKT A/S, Fredericia, (Denmark); Jensen, L.E. [LM Glasfiber A/S, Lunderskov (Denmark)

    2000-08-01

    This project has compiled data to allow the Danish manufacturers of wind turbines and blades to improve their knowledge of double stall. On the basis of the double stall difficulties different types of turbines using different makes of blades have encountered in the Tarifa area in Southern Spain, meteorological parameters and production data from two turbines have been measured for a local site. Part of the acquired data have been analysed to reach an understanding of why double stall occurs. The analysis strongly suggests that a change in power level due to double stall can be a result of several external factors: (1) Rain cleaning the blades. (2) A more or less random change in the wind speed components uv, or w, which in some cases can affect a - probably - fairly thick boundary layer. (3) A change in the high frequency turbulence where the vortex impact is too insignificant to affect an - almost - randomly - thick boundary layer. (au)

  17. Why Do Promising Therapies Stall in Development and How Can We Move Them Forward?

    Science.gov (United States)

    Wegner, Craig D; Goodwin, Andrew; Cook, Jon C; Allamneni, Krishna; Sohn, Jane; McVean, Maralee

    There are many reasons that molecules fail to progress to market and various principles of risk-benefit decisions that can help drive the molecule through development. This symposium included discussions on global strategies involved in pushing promising molecules to market, what to do when a molecule stalls in its progress to market, and options for rescuing the molecule and pushing it forward again. Innovative partnerships that bring stalled drugs back into clinical development were also addressed. A regulatory perspective on common reasons for a molecule to fail in its forward progress was presented. In addition, situations arise when a third-party advisory committee can provide input to help overcome issues identified by a regulatory agency. Using examples from the private and public domain, presentations centered on how to repurpose a molecule and when more science is needed.

  18. A Beddoes-Leishman type dynamic stall model in state-space and indicial formulations

    DEFF Research Database (Denmark)

    Hansen, M.H.; Gaunaa, Mac; Aagaard Madsen, Helge

    2004-01-01

    This report contains a description of a Beddoes-Leishman type dynamic stall model in both a state-space and an indicial function formulation. The model predicts the unsteady aerodynamic forces and moment on an airfoil section undergoing arbitrary motionin heave, lead-lag, and pitch. The model...... features, such as overshoot of the lift, in the stall region. The linearized model is shown to give identicalresults to the full model for small amplitude oscillations. Furthermore, it is shown that the response of finite thichkness airfoils can be reproduced to a high accuracy by the use of specific...... is carried out by comparing the response of the model with inviscid solutions and observing the general behavior of the model using known airfoil data as input. Theproposed dynamic model gives results identical to inviscid solutions within the attached-flow region; and it exhibits the expected dynamic...

  19. Grid support of a wind farm with active stall wind turbines and AC grid connection

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Sørensen, Poul Ejnar; Iov, F.

    2006-01-01

    grid connection. The designed control system has the task of enabling such a wind farm to provide the best grid support. It is based on two control levels: a supervisory control level, which controls the power production of the whole farm by sending out reference signals to each individual wind turbine......, and a local control level, which ensures that the reference power signals at the wind turbine level are reached. The ability of active stall wind farms with AC grid connection to control the power production to the reference power ordered by the operators is assessed and discussed by means of simulations.......One of the main concerns in the grid integration of large wind farms is their ability to behave as active controllable components in the power system. This article presents the design of a new integrated power control system for a wind farm made up exclusively of active stall wind turbines with AC...

  20. Simulation model of a transient fault controller for an active-stall wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, C.; Soerensen, P.; Bak Jensen, B.

    2005-01-01

    This paper describes the simulation model of a controller that enables an active-stall wind turbine to ride through transient faults. The simulated wind turbine is connected to a simple model of a power system. Certain fault scenarios are specified and the turbine shall be able to sustain operation in case of such faults. The design of the controller is described and its performance assessed by simulations. The control strategies are explained and the behaviour of the turbine discussed. (author)

  1. Ultrasonic superlensing jets and acoustic-fork sheets

    Energy Technology Data Exchange (ETDEWEB)

    Mitri, F.G., E-mail: F.G.Mitri@ieee.org

    2017-05-18

    Focusing acoustical (and optical) beams beyond the diffraction limit has remained a major challenge in imaging instruments and systems, until recent advances on “hyper” or “super” lensing and higher-resolution imaging techniques have shown the counterintuitive violation of this rule under certain circumstances. Nonetheless, the proposed technologies of super-resolution acoustical focusing beyond the diffraction barrier require complex tools such as artificially engineered metamaterials, and other hardware equipment that may not be easily synthesized or manufactured. The present contribution therefore suggests a simple and reliable method of using a sound-penetrable circular cylinder lens illuminated by a nonparaxial Gaussian acoustical sheet (i.e. finite beam in 2D) to produce non-evanescent ultrasonic superlensing jets (or bullets) and acoustical ‘snail-fork’ shaped wavefronts with limited diffraction. The generalized (near-field) scattering theory for acoustical sheets of arbitrary wavefronts and incidence is utilized to synthesize the incident beam based upon the angular spectrum decomposition method and the multipole expansion method in cylindrical wave functions to compute the scattered pressure around the cylinder with particular emphasis on its physical properties. The results show that depending on the beam and lens parameters, a tight focusing (with dimensions much smaller than the beam waist) can be achieved. Subwavelength resolution can be also achieved by selecting a lens material with a speed of sound exceeding that of the host fluid medium. The ultrasonic superlensing jets provide the impetus to develop improved subwavelength microscopy and acoustical image-slicing systems, cell lysis and surgery, and photoacoustic imaging to name a few examples. Moreover, an acoustical fork-sheet generation may open innovative avenues in reconfigurable on-chip micro/nanoparticle tweezers and surface acoustic waves devices. - Highlights: • Ultrasonic

  2. DksA guards elongating RNA polymerase against ribosome-stalling-induced arrest.

    Science.gov (United States)

    Zhang, Yan; Mooney, Rachel A; Grass, Jeffrey A; Sivaramakrishnan, Priya; Herman, Christophe; Landick, Robert; Wang, Jue D

    2014-03-06

    In bacteria, translation-transcription coupling inhibits RNA polymerase (RNAP) stalling. We present evidence suggesting that, upon amino acid starvation, inactive ribosomes promote rather than inhibit RNAP stalling. We developed an algorithm to evaluate genome-wide polymerase progression independently of local noise and used it to reveal that the transcription factor DksA inhibits promoter-proximal pausing and increases RNAP elongation when uncoupled from translation by depletion of charged tRNAs. DksA has minimal effect on RNAP elongation in vitro and on untranslated RNAs in vivo. In these cases, transcripts can form RNA structures that prevent backtracking. Thus, the effect of DksA on transcript elongation may occur primarily upon ribosome slowing/stalling or at promoter-proximal locations that limit the potential for RNA structure. We propose that inactive ribosomes prevent formation of backtrack-blocking mRNA structures and that, in this circumstance, DksA acts as a transcription elongation factor in vivo. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. An automatic system for the detection of dairy cows lying behaviour in free-stall barns

    Directory of Open Access Journals (Sweden)

    Simona M.C. Porto

    2013-09-01

    Full Text Available In this paper, a method for the automatic detection of dairy cow lying behaviour in free-stall barns is proposed. A computer visionbased system (CVBS composed of a video-recording system and a cow lying behaviour detector based on the Viola Jones algorithm was developed. The CVBS performance was tested in a head-to-head free stall barn. Two classifiers were implemented in the software component of the CVBS to obtain the cow lying behaviour detector. The CVBS was validated by comparing its detection results with those generated from visual recognition. This comparison allowed the following accuracy indices to be calculated: the branching factor (BF, the miss factor (MF, the sensitivity, and the quality percentage (QP. The MF value of approximately 0.09 showed that the CVBS missed one cow every 11 well detected cows. Conversely, the BF value of approximately 0.08 indicated that one false positive was detected every 13 well detected cows. The high value of approximately 0.92 obtained for the sensitivity index and that obtained for QP of about 0.85 revealed the ability of the proposed system to detect cows lying in the stalls.

  4. Piloted Simulator Evaluation Results of Flight Physics Based Stall Recovery Guidance

    Science.gov (United States)

    Lombaerts, Thomas; Schuet, Stefan; Stepanyan, Vahram; Kaneshige, John; Hardy, Gordon; Shish, Kimberlee; Robinson, Peter

    2018-01-01

    In recent studies, it has been observed that loss of control in flight is the most frequent primary cause of accidents. A significant share of accidents in this category can be remedied by upset prevention if possible, and by upset recovery if necessary, in this order of priorities. One of the most important upsets to be recovered from is stall. Recent accidents have shown that a correct stall recovery maneuver remains a big challenge in civil aviation, partly due to a lack of pilot training. A possible strategy to support the flight crew in this demanding context is calculating a recovery guidance signal, and showing this signal in an intuitive way on one of the cockpit displays, for example by means of the flight director. Different methods for calculating the recovery signal, one based on fast model predictive control and another using an energy based approach, have been evaluated in four relevant operational scenarios by experienced commercial as well as test pilots in the Vertical Motion Simulator at NASA Ames Research Center. Evaluation results show that this approach could be able to assist the pilots in executing a correct stall recovery maneuver.

  5. The Relationships between Selection and Processing Food with Escherichia coli Contaminant on Food Stall Serving

    Directory of Open Access Journals (Sweden)

    Tris Eryando

    2014-04-01

    Full Text Available Escherichia coli in food stalls surrounding the X Campuss in Depok, year 2012. The research conducted to examine food safety, which were served in surrounding the campus X in Depok. Escherichia coli (E. coli existence was used to indicate the quality of hygiene and sanitation of the food that was served. Using the cross sectional method, the research examined the persons who served the food to be sold in the food stalls in the campus. There were 173 food servers chosen as the respondents from 10 different food stalls around the university. The existence of E. coli examined in the microbiology laboratory in the Faculty of Public Health. Using the most probable number (MPN method found that 59.54% of the food served in the campus were contaminated E. coli. Factors affecting the existence of E. coli were the raw materials (vegetables treated and the length of cooking of the materials (rice/beens. The improper treatment such as washing with no running water or even unwashed vegetables had 5 times risk of the E. coli contamination. Cooking less than 15 minutes was also more risky than cooking more than 15 minutes. As a result, this is very important to find a method to improve knowledge and to increase practical skills in food safety. Furthermore, in this research area may give contribution to avoid E. coli contamination which will prevent unnecessary illness among students in the campus.

  6. Near Stall Flow Analysis in the Transonic Fan of the RTA Propulsion System

    Science.gov (United States)

    Hah, Chunill

    2010-01-01

    Turbine-based propulsion systems for access to space have been investigated at NASA Glenn Research center. A ground demonstrator engine for validation testing has been developed as a part of the program. The demonstrator, the Revolutionary Turbine Accelerator (RTA-1), is a variable cycle turbofan ramjet designed to transition from an augmented turbofan to a ramjet that produces the thrust required to accelerate the vehicle to Mach 4. The RTA-1 is designed to accommodate a large variation in bypass ratio from sea level static to Mach 4 flight condition. A key component of this engine is a new fan stage that accommodates these large variations in bypass ratio and flow ranges. In the present study, unsteady flow behavior in the fan of the RTA-1 is studied in detail with large eddy simulation (LES) and the numerical results are compared with measured data. During the experimental study of the fan stage, humming sound was detected at 100 % speed near stall operation. The main purpose of the study is to investigate details of the unsteady flow behavior at near stall operation and to identify a possible cause of the hum. The large eddy simulation of the current flow field reproduces main features of the measured flow very well. The LES simulation indicates that non-synchronous flow instability develops as the fan operates toward the stall limit. The FFT analysis of the calculated wall pressure shows that the rotating flow instability has the characteristic frequency that is about 50% of the blade passing frequency.

  7. Aire unleashes stalled RNA polymerase to induce ectopic gene expression in thymic epithelial cells.

    Science.gov (United States)

    Giraud, Matthieu; Yoshida, Hideyuki; Abramson, Jakub; Rahl, Peter B; Young, Richard A; Mathis, Diane; Benoist, Christophe

    2012-01-10

    Aire is a transcriptional regulator that induces expression of peripheral tissue antigens (PTA) in thymic medullary epithelial cells (MECs), driving immunological self-tolerance in differentiating T cells. To elucidate its mechanistic pathways, we examined its transcriptional impact in MECs in vivo by microarray analysis with mRNA-spanning probes. This analysis revealed initiation of Aire-activated genes to be comparable in Aire-deficient and wild-type MECs, but with a block to elongation after 50-100 bp in the absence of Aire, suggesting activation by release of stalled polymerases by Aire. In contrast, patterns of activation by transcription factors such as Klf4 were consistent with regulation of initiation. Mapping of Aire and RNA polymerase-II (Pol-II) by ChIP and high-throughput sequencing (ChIP-seq) revealed that Aire bound all Pol-II-rich transcriptional start sites (TSS), irrespective of its eventual effect. However, the genes it preferentially activated were characterized by a relative surfeit of stalled polymerases at the TSS, which resolved once Aire was introduced into cells. Thus, transcript mapping and ChIP-seq data indicate that Aire activates ectopic transcription not through specific recognition of PTA gene promoters but by releasing stalled polymerases.

  8. Short revolving wings enable hovering animals to avoid stall and reduce drag

    Science.gov (United States)

    Lentink, David; Kruyt, Jan W.; Heijst, Gertjan F.; Altshuler, Douglas L.

    2014-11-01

    Long and slender wings reduce the drag of airplanes, helicopters, and gliding animals, which operate at low angle of attack (incidence). Remarkably, there is no evidence for such influence of wing aspect ratio on the energetics of hovering animals that operate their wings at much higher incidence. High incidence causes aircraft wings to stall, hovering animals avoid stall by generating an attached vortex along the leading edge of their wings that elevates lift. Hypotheses that explain this capability include the necessity for a short radial distance between the shoulder joint and wing tip, measured in chord lengths, instead of the long tip-to-tip distance that elevates aircraft performance. This stems from how hovering animals revolve their wings around a joint, a condition for which the precise effect of aspect ratio on stall performance is unknown. Here we show that the attachment of the leading edge vortex is determined by wing aspect ratio with respect to the center of rotation-for a suite of aspect ratios that represent both animal and aircraft wings. The vortex remains attached when the local radius is shorter than 4 chord lengths, and separates outboard on more slender wings. Like most other hovering animals, hummingbirds have wing aspect ratios between 3 and 4, much stubbier than helicopters. Our results show this makes their wings robust against flow separation, which reduces drag below values obtained with more slender wings. This revises our understanding of how aspect ratio improves performance at low Reynolds numbers.

  9. Note: Enhanced energy harvesting from low-frequency magnetic fields utilizing magneto-mechano-electric composite tuning-fork.

    Science.gov (United States)

    Yang, Aichao; Li, Ping; Wen, Yumei; Yang, Chao; Wang, Decai; Zhang, Feng; Zhang, Jiajia

    2015-06-01

    A magnetic-field energy harvester using a low-frequency magneto-mechano-electric (MME) composite tuning-fork is proposed. This MME composite tuning-fork consists of a copper tuning fork with piezoelectric Pb(Zr(1-x)Ti(x))O3 (PZT) plates bonded near its fixed end and with NdFeB magnets attached at its free ends. Due to the resonance coupling between fork prongs, the MME composite tuning-fork owns strong vibration and high Q value. Experimental results show that the proposed magnetic-field energy harvester using the MME composite tuning-fork exhibits approximately 4 times larger maximum output voltage and 7.2 times higher maximum power than the conventional magnetic-field energy harvester using the MME composite cantilever.

  10. Stalled eruption or dike intrusion at Harrat Lunayyir, Saudi Arabia?

    Science.gov (United States)

    Zahran, H. M.; McCausland, W. A.; Pallister, J. S.; Lu, Z.; El-Hadidy, S.; Aburukba, A.; Schawali, J.; Kadi, K.; Youssef, A.; Ewert, J. W.; White, R. A.; Lundgren, P.; Mufti, M.; Stewart, I. C.

    2009-12-01

    ) Finally seismic data showed features similar to other volcanic swarms, including high rates of occurrence of small events, shallow event locations that clustered beneath the lava field and were coincident with the area of maximum deformation, RSAM values that peaked during periods of increased InSAR inflation, and a mixture of event types- high frequency, low frequency, possible very low frequency, and tremor. Based on our analysis of similar active volcanic systems worldwide and associated earthquakes in rift settings, we determined that for the three month period following 19 May 2009 there was a moderate probability that the activity could culminate in an eruption, and a very low probability of additional large earthquakes of M6 or greater. Subsequent to this hazard assessment and once the stability of structures in Al Ays was adequately addressed, the evacuees were allowed to return to their homes and daily lives.

  11. Biological monitoring program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Adams, S.M.; Ashwood, T.L.; Beaty, T.W.; Brandt, C.C.; Christensen, S.W.; Cicerone, D.S.; Greeley, M.S. Jr.; Hill, W.R.; Kszos, L.S.

    1997-04-18

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities.

  12. Soil Investigation of Lower East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Dickson, Johnbull O [ORNL; Mayes, Melanie [ORNL; Earles, Jennifer E [ORNL; Mehlhorn, Tonia L [ORNL; Lowe, Kenneth Alan [ORNL; Peterson, Mark J [ORNL; Pierce, Eric M [ORNL

    2017-03-01

    Mercury is regarded by the US Department of Energy (DOE) Oak Ridge Office of Environmental Management as a priority contaminant on the Oak Ridge Reservation because of the environmental risks associated with substantial losses from buildings, soils, and surface waters at the Y-12 National Security Complex (Y-12). As a result of historical releases of mercury from Y-12 primarily in the 1950s and early 1960s, the lower East Fork Poplar Creek (LEFPC) stream channel and bank soil margins are contaminated with mercury (Brooks and Southworth 2011; Tennessee Valley Authority 1985b, a). A Mercury Remediation Technology Development project is underway to evaluate the nature of downstream mercury contamination and to develop targeted site-specific remedial technologies that can mitigate mercury release and biological uptake. It is known that mercury concentration varies longitudinally and with depth in LEFPC bank soils; however, soil types and soil physical properties are not well known, especially relative to the zones of mercury contamination. Moreover, there are no soil maps for the downstream reaches of LEFPC in Roane County (i.e. from the Chestnut Hill Road downstream) and this work represents the first ever soil mapping along this section of LEFPC.

  13. Intestinal Fork Head Regulates Nutrient Absorption and Promotes Longevity

    Directory of Open Access Journals (Sweden)

    Ekin Bolukbasi

    2017-10-01

    Full Text Available Reduced activity of nutrient-sensing signaling networks can extend organismal lifespan, yet the underlying biology remains unclear. We show that the anti-aging effects of rapamycin and reduced intestinal insulin/insulin growth factor (IGF signaling (IIS require the Drosophila FoxA transcription factor homolog Fork Head (FKH. Intestinal FKH induction extends lifespan, highlighting a role for the gut. FKH binds to and is phosphorylated by AKT and Target of Rapamycin. Gut-specific FKH upregulation improves gut barrier function in aged flies. Additionally, it increases the expression of nutrient transporters, as does lowered IIS. Evolutionary conservation of this effect of lowered IIS is suggested by the upregulation of related nutrient transporters in insulin receptor substrate 1 knockout mouse intestine. Our study highlights a critical role played by FKH in the gut in mediating anti-aging effects of reduced IIS. Malnutrition caused by poor intestinal absorption is a major problem in the elderly, and a better understanding of the mechanisms involved will have important therapeutic implications for human aging.

  14. Failure analysis of axle shaft of a fork lift

    Directory of Open Access Journals (Sweden)

    Souvik Das

    2015-04-01

    Full Text Available An axle shaft of fork lift failed at operation within 296 h of service. The shaft transmits torque from discrepancy to wheel through planetary gear arrangement. A section of fractured axle shaft made of induction-hardened steel was analyzed to determine the root cause of the failure. Optical microscopies as well as field emission gun scanning electron microscopy (FEG-SEM along with energy dispersive spectroscopy (EDS were carried out to characterize the microstructure. Hardness profile throughout the cross-section was evaluated by micro-hardness measurements. Chemical analysis indicated that the shaft was made of 42CrMo4 steel grade as per specification. Microstructural analysis and micro-hardness profile revealed that the shaft was improperly heat treated resulting in a brittle case, where crack was found to initiate from the case in a brittle mode in contrast to ductile mode within the core. This behaviour was related to differences in microstructure, which was observed to be martensitic within the case with a micro-hardness equivalent to 735 HV, and a mixture of non-homogeneous structure of pearlite and ferrite within the core with a hardness of 210 HV. The analysis suggests that the fracture initiated from the martensitic case as brittle mode due to improper heat treatment process (high hardness. Moreover the inclusions along the hot working direction i.e. in the longitudinal axis made the component more susceptible to failure.

  15. BIOLOGICAL MONITORING PROGRAM FOR EAST FORK POPLAR CREEK

    Energy Technology Data Exchange (ETDEWEB)

    ADAMS, S.M.; ASHWOOD, T.L.; BEATY, T.W.; BRANDT, C.C.

    1997-10-24

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y- 12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities.

  16. The effect of alphacypermethrin-treated mesh protection against African horse sickness virus vectors on jet stall microclimate, clinical variables and faecal glucocorticoid metabolites of horses.

    Science.gov (United States)

    Page, Patrick; Ganswindt, Andre; Schoeman, Johan; Venter, Gert; Guthrie, Alan

    2017-09-09

    African horse sickness (AHS) is of importance to health and international trade in horses worldwide. During export from and transit through AHS endemic countries or zones, physical and chemical measures to protect horses from the vectors of AHS virus (AHSV) are recommended by the World Organization for Animal Health. Protection of containerized air transport systems for horses (jet stalls) with alphacypermethrin insecticide-treated high density polyethylene mesh is effective in reducing the Culicoides midge vector attack rate. In order to determine the effect of this mesh on jet stall ventilation and horse welfare under temperate climatic conditions, jet stall microclimate, clinical variables and faecal glucocorticoid metabolite (FGM) levels of 12 horses were monitored during overnight housing in either a treated or untreated stall in two blocks of a 2 × 3 randomized crossover design. Temperature difference between the treated stall and outside was significantly higher than the difference between the untreated stall and outside at 1/15 time points only (P = 0.045, r = 0.70). Relative humidity (RH) difference between the treated stall and outside did not differ from the untreated stall and outside. Temperature and RH in the treated stall were highly and significantly correlated with outside temperature (r = 0.96, P < 0.001) and RH (r = 0.95, P < 0.001), respectively. No significant differences were detected between rectal temperatures, pulse and respiratory rates of horses in the treated stall compared to the untreated stall. Mean FGM concentrations for horses housed in the treated stall peaked earlier (24 h) and at a higher concentration than horses housed in the untreated stall (48 h), but were not significantly different from baseline. No significant difference was detected in FGM concentrations when the treated and untreated stall groups were compared at individual time points up to 72 h after exiting the jet stall. Alphacypermethrin

  17. South Fork Snake River/Palisades Wildlife Mitigation Project: Environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    BPA proposes to fund the implementation of the South Fork Snake River Programmatic Management Plan to compensate for losses of wildlife and wildlife habitat due to hydroelectric development at Palisades Dam. The Idaho Department of Fish and Game drafted the plan, which was completed in May 1993. This plan recommends land and conservation easement acquisition and wildlife habitat enhancement measures. These measures would be implemented on selected lands along the South Fork of the Snake River between Palisades Dam and the confluence with the Henry`s Fork, and on portions of the Henry`s Fork located in Bonneville, Madison, and Jefferson Counties, Idaho. BPA has prepared an Environmental Assessment evaluating the proposed project. The EA also incorporates by reference the analyses in the South Fork Snake River Activity/Operations Plan and EA prepared jointly in 1991 by the Bureau of Land Management and the Forest Service. Based on the analysis in the EA, BPA has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an Environmental Impact Statement (EIS) is not required and BPA is issuing this FONSI.

  18. Final Environmental Assessment Addressing Riparian Restoration and Stabilization at Grand Forks Air Force Base, North Dakota

    Science.gov (United States)

    2012-09-01

    would include scotch pine ( Pinus sylvestris), blue spruce (Picea pungens), eastern red cedar (Juniperus virginiana), and rocky mountain juniper...reduces the germination of weed seeds, maintains soil moisture, and minimizes erosion. Wildlife. The project area provides diversity in habitat to...with native species. Soil should be covered to reduce the germination of weed seeds, maintain soil moisture, and minimize erosion.  4. Project

  19. Animal hygiene assessment of microclimate in semi open free-stall barns for dairy cows

    Directory of Open Access Journals (Sweden)

    D. Dimov

    2017-03-01

    Full Text Available Abstract. The study was conducted in three semi open free-stall barns (B1, B2, and B3 for dairy cows with capacities for 120, 120 and 500 cows, respectively, from three different dairy farms (F-1, F-2 and F-3, situated in Central Southern Bulgaria. The investigated farms had the same production system – loose housing in semi open free-stall dairy barn. For each of the farms the main microclimatic parameters – air temperature, relative humidity and speed of airflow were recorded twice a month at 10.00 h 12.00 h, 14.00 h, 16.00 h and 18.00 h of the day inside the barns in three main technological zones - above the stalls, above manure and feed alleys and outside the buildings. It was found that: a Microclimatic parameters (air temperature, air relative humidity and speed of airflow in technological zones (above the stalls, the manure and feed alleys of three semi open free-stall dairy barns meet the animal hygienic requirements for all seasons according to Regulation No. 44 (2006. Exceptions are some values of relative humidity in B1 and B2 in the spring, and in B1 in winter and summer, which are lower than the minimum humidity (50% according to the standard. b The investigated barns are characterized with poor insulation and do not provide enough isolation from the external ambient temperatures. With the exception of winter, the temperature of the air inside the buildings was lower than that outside, with minor differences for all seasons. The fans in the barns have no effect on the inside air temperature, especially in summer. There was a risk of higher temperatures mainly during the summer period. c There is no significant difference between the average temperatures, air humidity and speed of airflow in all technological zones of the investigated barns. d The largest and statistically significant is the difference between the relative air humidity outside and inside the building in Farm 3, followed by buildings in Farm 1 and 2, where the

  20. [History of the tuning fork. I: Invention of the tuning fork, its course in music and natural sciences. Pictures from the history of otorhinolaryngology, presented by instruments from the collection of the Ingolstadt German Medical History Museum].

    Science.gov (United States)

    Feldmann, H

    1997-02-01

    G. Cardano, physician, mathematician, and astrologer in Pavia, Italy, in 1550 described how sound may be perceived through the skull. A few years later H. Capivacci, also a physician in Padua, realized that this phenomenon might be used as a diagnostic tool for differentiating between hearing disorders located either in the middle ear or in the acoustic nerve. The German physician G. C. Schelhammer in 1684 was the first to use a common cutlery fork in further developing the experiments initiated by Cardano and Capivacci. For a long time to come, however, there was no demand for this in practical otology. The tuning fork was invented in 1711 by John Shore, trumpeter and lutenist to H. Purcell and G.F. Händel in London. A picture of Händel's own tuning fork, probably the oldest tuning fork in existence, is presented here for the first time. There are a number of anecdotes connected with the inventor of the tuning fork, using plays on words involving the name Shore, and mixing up pitch-pipe and pitchfork. Some of these are related here. The tuning fork as a musical instrument soon became a success throughout Europe. The German physicist E. F. F. Chladni in Wittenberg around 1800 was the first to systematically investigate the mode of vibration of the tuning fork with its nodal points. Besides this, he and others tried to construct a complete musical instrument based on sets of tuning forks, which, however, were not widely accepted. J. H. Scheibler in Germany in 1834 presented a set of 54 tuning forks covering the range from 220 Hz to 440 Hz, at intervals of 4 Hz. J. Lissajous in Paris constructed a very elaborate tuning fork with a resonance box, which was intended to represent the international standard of the musical note A with 435 vibrations per second, but this remained controversial. K. R. Koenig, a German physicist living in Paris, invented a tuning fork which was kept in continuous vibration by a clockwork. H. Helmholtz, physiologist in Heidelberg, in 1863

  1. Prediction of RNA Polymerase II recruitment, elongation and stalling from histone modification data

    Science.gov (United States)

    2011-01-01

    Background Initiation and elongation of RNA polymerase II (RNAPII) transcription is regulated by both DNA sequence and chromatin signals. Recent breakthroughs make it possible to measure the chromatin state and activity of core promoters genome-wide, but dedicated computational strategies are needed to progress from descriptive annotation of data to quantitative, predictive models. Results Here, we describe a computational framework which with high accuracy can predict the locations of core promoters, the amount of recruited RNAPII at the promoter, the amount of elongating RNAPII in the gene body, the mRNA production originating from the promoter and finally also the stalling characteristics of RNAPII by considering both quantitative and spatial features of histone modifications around the transcription start site (TSS). As the model framework can also pinpoint the signals that are the most influential for prediction, it can be used to infer underlying regulatory biology. For example, we show that the H3K4 di- and tri- methylation signals are strongly predictive for promoter location while the acetylation marks H3K9 and H3K27 are highly important in estimating the promoter usage. All of these four marks are found to be necessary for recruitment of RNAPII but not sufficient for the elongation. We also show that the spatial distributions of histone marks are almost as predictive as the signal strength and that a set of histone marks immediately downstream of the TSS is highly predictive of RNAPII stalling. Conclusions In this study we introduce a general framework to accurately predict the level of RNAPII recruitment, elongation, stalling and mRNA expression from chromatin signals. The versatility of the method also makes it ideally suited to investigate other genomic data. PMID:22047616

  2. Prediction of RNA Polymerase II recruitment, elongation and stalling from histone modification data

    Directory of Open Access Journals (Sweden)

    Chen Yun

    2011-11-01

    Full Text Available Abstract Background Initiation and elongation of RNA polymerase II (RNAPII transcription is regulated by both DNA sequence and chromatin signals. Recent breakthroughs make it possible to measure the chromatin state and activity of core promoters genome-wide, but dedicated computational strategies are needed to progress from descriptive annotation of data to quantitative, predictive models. Results Here, we describe a computational framework which with high accuracy can predict the locations of core promoters, the amount of recruited RNAPII at the promoter, the amount of elongating RNAPII in the gene body, the mRNA production originating from the promoter and finally also the stalling characteristics of RNAPII by considering both quantitative and spatial features of histone modifications around the transcription start site (TSS. As the model framework can also pinpoint the signals that are the most influential for prediction, it can be used to infer underlying regulatory biology. For example, we show that the H3K4 di- and tri- methylation signals are strongly predictive for promoter location while the acetylation marks H3K9 and H3K27 are highly important in estimating the promoter usage. All of these four marks are found to be necessary for recruitment of RNAPII but not sufficient for the elongation. We also show that the spatial distributions of histone marks are almost as predictive as the signal strength and that a set of histone marks immediately downstream of the TSS is highly predictive of RNAPII stalling. Conclusions In this study we introduce a general framework to accurately predict the level of RNAPII recruitment, elongation, stalling and mRNA expression from chromatin signals. The versatility of the method also makes it ideally suited to investigate other genomic data.

  3. Study on vacuum packaging reliability of micromachined quartz tuning fork gyroscopes

    Science.gov (United States)

    Fan, Maoyan; Zhang, Lifang

    2017-09-01

    Packaging technology of the micromachined quartz tuning fork gyroscopes by vacuum welding has been experimentally studied. The performance of quartz tuning fork is influenced by the encapsulation shell, encapsulation method and fixation of forks. Alloy solder thick film is widely used in the package to avoid the damage of the chip structure by the heat resistance and hot temperature, and this can improve the device performance and welding reliability. The results show that the bases and the lids plated with gold and nickel can significantly improve the airtightness and reliability of the vacuum package. Vacuum packaging is an effective method to reduce the vibration damping, improve the quality factor and further enhance the performance. The threshold can be improved nearly by 10 times.

  4. Stall, Spiculate, or Run Away: The Fate of Fibers Growing towards Fluctuating Membranes

    Science.gov (United States)

    Daniels, D. R.; Marenduzzo, D.; Turner, M. S.

    2006-09-01

    We study the dynamics of a growing semiflexible fiber approaching a membrane at an angle. At late times we find three regimes: fiber stalling, when growth stops, runaway, in which the fiber bends away from the membrane, and another regime in which spicules form. We discuss which regions of the resulting “phase diagram” are explored by (i) single and bundled actin fibers in living cells, (ii) sickle hemoglobin fibers, and (iii) microtubules inside vesicles. We complement our analysis with 3D stochastic simulations.

  5. Prediction of H.A.W.T. blade stall and performance

    Energy Technology Data Exchange (ETDEWEB)

    Giannakidis, G.; Graham, J.M.R. [Imperial College, Dept. of Aeronautics, London (United Kingdom)

    1996-09-01

    A model is being developed for the prediction of Horizontal Axis Wind Turbine blade stall and performance coupled with a simple aeroelastic analysis model. For the aerodynamic calculation a two dimensional unsteady Navier-Stokes solver on a sectional basis on the blade is coupled with a three dimensional vortex lattice wake. Pressure coefficient distributions are calculated from the two dimensional viscous flow in each blade section. The aerodynamic computations are coupled with a vibrating beam model in order to incorporate flapwise deformations of the blade. (au) 17 refs.

  6. Modeling dynamic stall on wind turbine blades under rotationally augmented flow fields

    DEFF Research Database (Denmark)

    Guntur, Srinivas; Sørensen, Niels N.; Schreck, Scott

    2016-01-01

    Experiment Phase VI experimental data, including constant as well as continuously pitching blade conditions during axial operation; (2) data from unsteady delayed detached eddy simulations (DDES) carried out using the Technical University of Denmark’s in-house flow solver Ellipsys3D; and (3) data from...... agreement between the model and the experimental data in many cases, which suggests that the current two-dimensional dynamic stall model as used in blade element momentum-based aeroelastic codes may provide a reasonably accurate representation of three-dimensional rotor aerodynamics when used in combination...

  7. 77 FR 64125 - Notice of Proposed Withdrawal Extension and Notification of a Public Meeting for the East Fork...

    Science.gov (United States)

    2012-10-18

    ... States mining laws, to protect the East Fork Elk Winter Range and elk natural feeding grounds in Fremont... and announces the date, time, and location of a public meeting. ] DATES: We must receive comments on... mineral estate from location or entry under the United States mining laws, to protect the East Fork Elk...

  8. Burnup verification tests with the FORK measurement system-implementation for burnup credit

    International Nuclear Information System (INIS)

    Ewing, R.I.

    1994-01-01

    Verification measurements may be used to help ensure nuclear criticality safety when burnup credit is applied to spent fuel transport and storage systems. The FORK system measures the passive neutron and gamma-ray emission from spent fuel assemblies while in the storage pool. It was designed at Los Alamos National Laboratory for the International Atomic Energy Agency safeguards program and is well suited to verify burnup and cooling time records at commercial Pressurized Water Reactor (PWR) sites. This report deals with the application of the FORK system to burnup credit operations

  9. Reconnaissance for radioactive deposits in the Nixon Fork mining district, Medfra Quadrangle, central Alaska, 1949

    Science.gov (United States)

    White, Max G.; Stevens, John M.

    1953-01-01

    Reconnaissance for radioactive deposits in the Nixon Fork mining district, Medfra quadrangle, central Alaska, in 1949 disclosed the occurrence of allanite in sampled containing as much as 0.05 percent equivalent uranium from the dump of the Whalen mine; the presence of radioactive parisite (a rare-earth fluocarbonate) in a highly altered limestone containing about 0.025 percent equivalent uranium near the Whalen shaft; and radioactive idocrase in samples of altered garnet rock with about 0.025 percent equivalent uranium, form the Crystal shaft of the Nixon Fork mine. This radioactivity is due mostly to thorium rather than uranium. Placer concentrates

  10. Characterization of RACK7 as a Novel Factor Involved in BRCA1 Mutation Mediated Breast Cancer

    Science.gov (United States)

    2012-10-01

    purify a ZMYND8 fragment encompassing the phosphorylation site from bacteria for the use in immune-complex kinase assays, in order to show that ATM is...completed by the firing of dormant origins20,21. Altogether, neither the mechanism of fork stabilization nor the events occurring during stalling are well...P. Replication fork reversal and the maintenance of genome stability. Nucleic Acids Res 37, 3475-3492 (2009). 7. Petermann, E. & Helleday, T

  11. Modelling of multiple short-length-scale stall cells in an axial compressor using evolved GMDH neural networks

    International Nuclear Information System (INIS)

    Amanifard, N.; Nariman-Zadeh, N.; Farahani, M.H.; Khalkhali, A.

    2008-01-01

    Over the past 15 years there have been several research efforts to capture the stall inception nature in axial flow compressors. However previous analytical models could not explain the formation of short-length-scale stall cells. This paper provides a new model based on evolved GMDH neural network for transient evolution of multiple short-length-scale stall cells in an axial compressor. Genetic Algorithms (GAs) are also employed for optimal design of connectivity configuration of such GMDH-type neural networks. In this way, low-pass filter (LPF) pressure trace near the rotor leading edge is modelled with respect to the variation of pressure coefficient, flow rate coefficient, and number of rotor rotations which are defined as inputs

  12. DAILY TIME BUDGET OF DAIRY COWS HOUSED IN TIE STALL BARNS, DURING TOTAL CONFINEMENT

    Directory of Open Access Journals (Sweden)

    D. GAVOJDIAN

    2009-10-01

    Full Text Available Although individual and social behavior of cattle has been studied extensively under pasture and loose housing conditions, similar behavioral data for partial or total confinement housing are limited. Essentially, the 24- h time budget represents the net response of a cow to her environment (Grant, 2003. Daily time budget was first introduced by Grant and Albright (in 2000 for cows housed in free-stall environment. Choices in stabling and management affect the behavior, health, longevity and performance of cows. Behavior while resting, eating, ruminating, urinating or defecating provides additional information about comfort. In the current study were used ten Romanian Black and White multiparous cows, housed in a tie stall barn 24 hours per day. Experiments were carried out during the cold season, in February 2008. Cows monitored were in their first hundred days of lactation. In our study cows spent resting on average 379.9 minutes (6.33 hours, value that represents 26.38 % from the days interval. Time devoted to feeding was on average 341.9 minutes (5.69 hours, in 17.5 periods. Rumination had place on average in 17.3 periods and a total time of 517.5 minutes (8.62 hours. Cows adopted lying position on average 581.2 minutes (40.36% from 24-h and standing position on average in 858.7 minutes (59.63% from 24-h.

  13. Numerical study on a single bladed vertical axis wind turbine under dynamic stall

    Energy Technology Data Exchange (ETDEWEB)

    Bangga, Galih [Institute of Aerodynamics and Gas Dynamics, University of Stuttgart, Stuttgart (Germany); Hutomo, Go; Sasongko, Herman [Dept. of Mechanical Engineering, Institut Teknologi Sepuluh Nopember, Surabaya (Indonesia); Wiranegara, Raditya [School of Mechanical Aerospace and Civil Engineering, University of Manchester, Manchester (United Kingdom)

    2017-01-15

    The aim of this study is to investigate the flow development of a single bladed vertical axis wind turbine using Computational fluid dynamics (CFD) methods. The blade is constructed using the NACA 0012 profile and is operating under stalled conditions at tip speed ratio of 2. Two dimensional simulations are performed using a commercial CFD package, ANSYS Fluent 15.0, employing the Menter-SST turbulence model. For the preliminary study, simulations of the NACA 0012 airfoil under static conditions are carried out and compared with available measurement data and calculations using the boundary layer code XFOIL. The CFD results under the dynamic case are presented and the resulting aerodynamic forces are evaluated. The turbine is observed to generate negative power at certain azimuth angles which can be divided into three main zones. The blade vortex interaction is observed to strongly influence the flow behavior near the blade and contributes to the power production loss. However, the impact is considered small since it covers only 6.4 % of the azimuth angle range where the power is negative compared to the dynamic stall impact which covers almost 22 % of the azimuth angle range.

  14. Wind-up of a spanwise vortex in deepening transition and stall

    Energy Technology Data Exchange (ETDEWEB)

    Smith, F.T.; Bowles, R.I. [University Coll., London (United Kingdom). Dept. of Mathematics; Walker, J.D.A. [Mechanical Engineering Department, Packard Laboratory No. 19, Lehigh University, Bethlehem, PA 18015 (United States)

    2000-09-01

    A fundamental flow problem of unsteady wind-up of a spanwise vortex is studied in this theoretical work on deepening dynamic stall and transition in a boundary layer, internal layer or related unsteady motion. It examines the nonlinear evolution of the spanwise vortex produced when the local wall pressure develops a maximum or minimum, subsequent to the finite-time break-up of an interacting layer and the impact of normal pressure gradients. The evolution is controlled by an inner-outer interaction between the effects of the normal pressure gradient and the momentum jumps across and outside the vortex, which is situated near the strong inflexion point induced in the mean flow. Although the work concentrates on a particular internal-flow context, many of the flow properties found are generic and in particular apply for a more general case including external flows. Analysis and associated computations point to two main distinct trends in the vortex response, depending to a large extent on a parameter gauging the relative strengths of the above effects. The response is either an explosive one, provoking enhanced wind-up, growth and pressure in the vortex, or it is implosive, causing the vortex to shrink and virtually empty itself through unwinding, leaving little local pressure variation. A further discussion includes the after-effects of this vortex response and some of the connections with experiments and direct computations on deepening stall and transition. (orig.)

  15. Experimental Methods Applied in a Study of Stall Flutter in an Axial Flow Fan

    Directory of Open Access Journals (Sweden)

    John D. Gill

    2004-01-01

    Full Text Available Flutter testing is an integral part of aircraft gas turbine engine development. In typical flutter testing blade mounted sensors in the form of strain gages and casing mounted sensors in the form of light probes (NSMS are used. Casing mounted sensors have the advantage of being non-intrusive and can detect the vibratory response of each rotating blade. Other types of casing mounted sensors can also be used to detect flutter of rotating blades. In this investigation casing mounted high frequency response pressure transducers are used to characterize the part-speed stall flutter response of a single stage unshrouded axial-flow fan. These dynamic pressure transducers are evenly spaced around the circumference at a constant axial location upstream of the fan blade leading edge plane. The pre-recorded experimental data at 70% corrected speed is analyzed for the case where the fan is back-pressured into the stall flutter zone. The experimental data is analyzed using two probe and multi-probe techniques. The analysis techniques for each method are presented. Results from these two analysis methods indicate that flutter occurred at a frequency of 411 Hz with a dominant nodal diameter of 2. The multi-probe analysis technique is a valuable method that can be used to investigate the initiation of flutter in turbomachines.

  16. Active flow control of the laminar separation bubble on a plunging airfoil near stall

    Science.gov (United States)

    Pande, Arth; Agate, Mark; Little, Jesse; Fasel, Hermann

    2017-11-01

    The effects of small amplitude (A/c = 0.048) high frequency (πfc/U∞ = 0.70) plunging motion on the X-56A airfoil are examined experimentally at Re = 200,000 for 12° angle of attack (CL,MAX = 12.25°) . The purpose of this research is to study the aerodynamic influence of structural motion when the wing is vibrating close to its eigenfrequency near static stall. Specific focus is placed on the laminar separation bubble (LSB) near the leading edge and its control via plasma actuation. In the baseline case, the leading edge bubble bursts during the oscillation cycle causing moment stall. A collaborative computational effort has shown that small amplitude forcing at a frequency that is most amplified by the primary instability of the LSB (FLSB+= 1, Fc+= 52) generates coherent spanwise vortices that entrain freestream momentum, thus reducing separation all while maintaining a laminar flow state. Results (PIV and surface pressure) indicate that a similar control mechanism is effective in the experiments. This is significant given the existence of freestream turbulence in the wind tunnel which has been shown to limit the efficacy of this active flow control technique in a model problem using Direct Numerical Simulation. The implications of these results are discussed.

  17. Compliance with NAGCAT work practices recommendations for youth cleaning service alleys in stall barns.

    Science.gov (United States)

    Canan, B D; Asti, L; Heaney, C; Ashida, S; Renick, K; Xiang, H; Stallones, L; Jepsen, S D; Crawford, J M; Wilkins, J R

    2011-04-01

    Unintentional injury is the leading cause of death in the U.S. among persons 1 to 44 years of age. Over one million children and adolescents in the U.S. live, work, and/or play on farms, where injury risk is relatively high compared to other settings. In an attempt to reduce the number of childhood agricultural injuries occurring on farms, the North American Guidelines for Children's Agricultural Tasks (NAGCAT) was developed to assist parents or other caregivers in assigning developmentally appropriate chores to youth exposed to agricultural hazards. The results presented here are from a longitudinal study in which we obtained (self-reported) daily chore, injury, and safety behavior data from children and adolescents. We focused on one NAGCAT chore, cleaning a service alley in a stall barn, in order to estimate the extent of compliance with specific work practice recommendations contained in the NAGCAT. Our results indicated that among the four NAGCAT-recommended safety practices for cleaning service alleys in stall barns (wearing nonskid shoes, leather gloves, a respirator, and eye protection), wearing non-skid shoes was the only safety practice reported with any degree of regularity. Overall, boys were more likely to wear non-skid shoes compared to girls. In addition, older youth were generally more likely to report higher work practice compliance compared to younger youth.

  18. Ethnic Dimensions of Guatemala's Stalled Transition: A Parity-Specific Analysis of Ladino and Indigenous Fertility Regimes.

    Science.gov (United States)

    Grace, Kathryn; Sweeney, Stuart

    2016-02-01

    In some contemporary populations, fertility levels appear to plateau, with women maintaining a consistently high level of fertility for a relatively extended period. Because this plateau does not reflect the historical patterns observed in Europe, the focus of most studies on fertility patterns, mechanisms underlying the plateau and the reinstatement of a decline have not been fully explored and are not fully understood. Through the construction of fertility histories of 25,000 women using multiple years of health survey data, we analyze some of the components of stalled fertility as they pertain to Guatemala, the only Central American country to have experienced a stalled fertility decline.

  19. Storm water control plan for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-04-01

    This document provides the Environmental Restoration Program with information about the erosion and sediment control, storm water management, maintenance, and reporting and record keeping practices to be employed during Phase II of the remediation project for the Lower East Fork Poplar Creek (LEFPC) Operable Unit

  20. Dynamic DNA Helicase-DNA Polymerase Interactions Assure Processive Replication Fork Movement

    NARCIS (Netherlands)

    Hamdan, Samir M.; Johnson, Donald E.; Tanner, Nathan A.; Lee, Jong-Bong; Qimron, Udi; Tabor, Stanley; Oijen, Antoine M. van; Richardson, Charles C.

    2007-01-01

    A single copy of bacteriophage T7 DNA polymerase and DNA helicase advance the replication fork with a processivity greater than 17,000 nucleotides. Nonetheless, the polymerase transiently dissociates from the DNA without leaving the replisome. Ensemble and single-molecule techniques demonstrate that

  1. Stream bank and sediment movement associated with 2008 flooding, South Fork Iowa River

    Science.gov (United States)

    Stream bank erosion can cause substantial damage to riparian systems and impact the use of water downstream. Risks of bank erosion increase during extreme flood events, and frequencies of extreme events may be increasing under changing climate. We assessed bank erosion within the South Fork Iowa Riv...

  2. From farm to fork and further. Research tackling the grand challenge of food safety in Europe

    NARCIS (Netherlands)

    Ridder, M. de; Polchar, J.; Gehem, M.

    2012-01-01

    The study From Farm to Fork and Further shows how, as traditional causes of food safety problems such as basic hygiene are successfully dealt with, future food safety risks become ever harder to manage. European countries may have the highest food safety standards, however the trends that go hand in

  3. Noncontact atomic force microscopy in liquid environment with quartz tuning fork and carbon nanotube probe

    DEFF Research Database (Denmark)

    Kageshima, M.; Jensenius, Henriette; Dienwiebel, M.

    2002-01-01

    A force sensor for noncontact atomic force microscopy in liquid environment was developed by combining a multiwalled carbon nanotube (MWNT) probe with a quartz tuning fork. Solvation shells of octamethylcyclotetrasiloxane surface were detected both in the frequency shift and dissipation. Due...

  4. 77 FR 47058 - Middle Fork American River Hydroelectric Project Placer County Water Agency; Notice of Draft...

    Science.gov (United States)

    2012-08-07

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [P-2079-069--CA] Middle Fork American River Hydroelectric Project Placer County Water Agency; Notice of Draft Environmental Impact Statement; Public Meetings a. Date and Time of Meetings: Tuesday, August 28, 2012, from 9:00 a.m. to 11:00 a.m. and...

  5. The progression of replication forks at natural replication barriers in live bacteria

    NARCIS (Netherlands)

    Moolman, M.C.; Tiruvadi Krishnan, S; Kerssemakers, J.W.J.; de Leeuw, R.; Lorent, V.J.F.; Sherratt, David J.; Dekker, N.H.

    2016-01-01

    Protein-DNA complexes are one of the principal barriers the replisome encounters during replication. One such barrier is the Tus-ter complex, which is a direction dependent barrier for replication fork progression. The details concerning the dynamics of the replisome when encountering these

  6. 76 FR 6114 - Lincoln National Forest, New Mexico, North Fork Eagle Creek Wells Special Use Authorization

    Science.gov (United States)

    2011-02-03

    ... before the wells began pumping in 1988. When groundwater is pumped from the North Fork wells, it causes a temporary decline in groundwater which lowers the water table and creates an expanding cone of depression around the wells. If the cone of depression continues to expand, it can impact water dependent resources...

  7. Dual parasitism of Fork-tailed Drongos by African and Jacobin ...

    African Journals Online (AJOL)

    Different species of brood parasitic birds, which lay their eggs in the nests of host foster-parents, rarely target the same host species population. We report brood parasitism of Fork-tailed Drongos Dicrurus adsimilis in the southern Kalahari Desert by both African Cuckoo Cuculus gularis and Jacobin Cuckoo Clamator ...

  8. 76 FR 35909 - Temporary Concession Contract for Big South Fork National Recreation Area, TN/KY

    Science.gov (United States)

    2011-06-20

    ... years. The visitor services include providing backcountry lodging accommodations, food and beverage, and... DEPARTMENT OF THE INTERIOR National Park Service [[NPS-WASO-CONC-0511-7144; 2410-OYC] Temporary Concession Contract for Big South Fork National Recreation Area, TN/KY AGENCY: National Park Service...

  9. Casimir force experiments with quartz tuning forks and an atomic force microscope (AFM)

    International Nuclear Information System (INIS)

    Ludwig, T

    2008-01-01

    The aim of the measurement series is to study the Casimir force, specifically the effects of different materials and geometries. The art of measuring sub-nano Newton forces has been engineered to a great extent in the material sciences, especially for the atomic force microscope. In today's scanning microscope technologies there are several common methods used to measure sub-nano Newton forces. While the commercial atomic force microscopes (AFM) mostly work with soft silicon cantilevers, there are a large number of reports from university groups on the use of quartz tuning forks to get high resolution AFM pictures, to measure shear forces or to create new force sensors. The quartz tuning fork based force sensor has a number of advantages over the silicon cantilever, but also has some disadvantages. In this report the method based on quartz tuning forks is described with respect to their usability for Casimir force measurements and compared with other successful techniques. Furthermore, a design for Casimir force measurements that was set up in Berlin will be described and practical experimental aspects will be discussed. A status report on the Casimir experiments in Berlin will be given, including the experimental setup. In order to study the details of the Casimir effect the apparatus and active surfaces have to be improved further. The surfaces have to be flatter and cleaner. For better resolution, cantilevers and tuning forks with a low spring constant have to be employed

  10. Mammalian RAD52 Functions in Break-Induced Replication Repair of Collapsed DNA Replication Forks

    DEFF Research Database (Denmark)

    Sotiriou, Sotirios K; Kamileri, Irene; Lugli, Natalia

    2016-01-01

    RNA or knockout of the gene by CRISPR/Cas9 compromised restart of collapsed forks and led to DNA damage in cells experiencing DRS. Furthermore, in cancer-prone, heterozygous APC mutant mice, homozygous deletion of the Rad52 gene suppressed tumor growth and prolonged lifespan. We therefore propose that mammalian...

  11. New aspects of protein stability and turnover in the regulation of genome integrity

    DEFF Research Database (Denmark)

    Gallina, Irene

    -scale studies investigating factors involved in DNA metabolism, but no specific function has been assigned to Cmr1. Taking advantage of a series of high-throughput screens we characterize Cmr1 as a chromatinassociated protein, involved in the regulation of fork progression in the presence of replication stress....... Moreover, we dissect the association of Cmr1 and other nuclear and cytoplasmic proteins to the JUNQ compartment in response to replication stress, and propose a model where relocalization of replication-associated factors to the nuclear periphery is important for promoting fork stability and recovery after...... replication stress...

  12. Spins, Stalls, and Shutdowns: Pitfalls of Qualitative Policing and Security Research

    Directory of Open Access Journals (Sweden)

    Randy K. Lippert

    2015-11-01

    Full Text Available This article explores key elements of qualitative research on policing and security agencies, including barriers encountered and strategies to prevent them. While it is oft-assumed that policing/security agencies are difficult to access due to their clandestine or bureaucratic nature, this article demonstrates this is not necessarily the case, as access was gained for three distinct qualitative research projects. Yet, access and subsequent research were not without pitfalls, which we term security spins, security stalls, and security shutdowns. We illustrate how each was encountered and argue these pitfalls are akin to researchers falling into risk categories, not unlike those used by policing/security agents in their work. Before concluding we discuss methodological strategies for scholars to avoid these pitfalls and to advance research that critically interrogates the immense policing/security realm. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1601108

  13. URANS simulations of separated flow with stall cells over an NREL S826 airfoil

    Science.gov (United States)

    Sarlak, H.; Nishino, T.; Sørensen, J. N.

    2016-06-01

    A series of wind tunnel measurements and oil flow visualization was recently carried out at the Technical University of Denmark in order to investigate flow characteristics over a 14% thick NREL S826 airfoil at low Reynolds numbers. This paper aims at presenting numerical simulations of the same airfoil using unsteady Reynolds-averaged Navier-Stokes (URANS) approach. Results of the simulations are demonstrated in terms of mean flow velocity, lift and drag, as well as pressure distribution, and validated against available experimental data. The simulations are carried out with a wide computational domain (with a span-to-chord ratio of 5) and it is illustrated that the URANS approach is capable of predicting 3D spanwise structures, known as stall cells.

  14. Performance augmentation with vortex generators: Design and testing for stall-regulated AWT-26 turbine

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, D.A. [Advanced Wind Turbines Inc., Seattle, WA (United States)

    1996-12-31

    A study investigated the use of vortex generators (VGs) for performance augmentation of the stall-regulated AWT-26 wind turbine. Based on wind-tunnel results and analysis, a VG array was designed for and tested on the AWT-26 prototype, designated Pt. Performance and loads data were measured for P1, both with and without VGs installed. The turbine performance with VGs met most of the design requirements; power output was increased at moderate wind speeds with a minimal effect on peak power. However, VG drag penalties caused a loss in power output for low wind speeds, such that performance with VGs resulted in a net decrease in AEP for wind speed sites up to 8.5 m/s. 8 refs., 8 figs., 3 tabs.

  15. Listeria phospholipases subvert host autophagic defenses by stalling pre-autophagosomal structures

    Science.gov (United States)

    Tattoli, Ivan; Sorbara, Matthew T; Yang, Chloe; Tooze, Sharon A; Philpott, Dana J; Girardin, Stephen E

    2013-01-01

    Listeria can escape host autophagy defense pathways through mechanisms that remain poorly understood. We show here that in epithelial cells, Listeriolysin (LLO)-dependent cytosolic escape of Listeria triggered a transient amino-acid starvation host response characterized by GCN2 phosphorylation, ATF3 induction and mTOR inhibition, the latter favouring a pro-autophagic cellular environment. Surprisingly, rapid recovery of mTOR signalling was neither sufficient nor necessary for Listeria avoidance of autophagic targeting. Instead, we observed that Listeria phospholipases PlcA and PlcB reduced autophagic flux and phosphatidylinositol 3-phosphate (PI3P) levels, causing pre-autophagosomal structure stalling and preventing efficient targeting of cytosolic bacteria. In co-infection experiments, wild-type Listeria protected PlcA/B-deficient bacteria from autophagy-mediated clearance. Thus, our results uncover a critical role for Listeria phospholipases C in the inhibition of autophagic flux, favouring bacterial escape from host autophagic defense. PMID:24162724

  16. Damage-induced DNA replication stalling relies on MAPK-activated protein kinase 2 activity

    DEFF Research Database (Denmark)

    Köpper, Frederik; Bierwirth, Cathrin; Schön, Margarete

    2013-01-01

    DNA damage can obstruct replication forks, resulting in replicative stress. By siRNA screening, we identified kinases involved in the accumulation of phosphohistone 2AX (γH2AX) upon UV irradiation-induced replication stress. Surprisingly, the strongest reduction of phosphohistone 2AX followed...... knockdown of the MAP kinase-activated protein kinase 2 (MK2), a kinase currently implicated in p38 stress signaling and G2 arrest. Depletion or inhibition of MK2 also protected cells from DNA damage-induced cell death, and mice deficient for MK2 displayed decreased apoptosis in the skin upon UV irradiation...... replication impaired by gemcitabine or by Chk1 inhibition. This rescue strictly depended on translesion DNA polymerases. In conclusion, instead of being an unavoidable consequence of DNA damage, alterations of replication speed and origin firing depend on MK2-mediated signaling....

  17. Study of Near-Stall Flow Behavior in a Modern Transonic Fan with Composite Sweep

    Science.gov (United States)

    Hah, Chunill; Shin, Hyoun-Woo

    2011-01-01

    Detailed flow behavior in a modern transonic fan with a composite sweep is investigated in this paper. Both unsteady Reynolds-averaged Navier-Stokes (URANS) and Large Eddy Simulation (LES) methods are applied to investigate the flow field over a wide operating range. The calculated flow fields are compared with the data from an array of high-frequency response pressure transducers embedded in the fan casing. The current study shows that a relatively fine computational grid is required to resolve the flow field adequately and to calculate the pressure rise across the fan correctly. The calculated flow field shows detailed flow structure near the fan rotor tip region. Due to the introduction of composite sweep toward the rotor tip, the flow structure at the rotor tip is much more stable compared to that of the conventional blade design. The passage shock stays very close to the leading edge at the rotor tip even at the throttle limit. On the other hand, the passage shock becomes stronger and detaches earlier from the blade passage at the radius where the blade sweep is in the opposite direction. The interaction between the tip clearance vortex and the passage shock becomes intense as the fan operates toward the stall limit, and tip clearance vortex breakdown occurs at near-stall operation. URANS calculates the time-averaged flow field fairly well. Details of measured RMS static pressure are not calculated with sufficient accuracy with URANS. On the other hand, LES calculates details of the measured unsteady flow features in the current transonic fan with composite sweep fairly well and reveals the flow mechanism behind the measured unsteady flow field.

  18. Benchmarking welfare indicators in 73 free-stall dairy farms in north-western Spain

    Science.gov (United States)

    Trillo, Yolanda; Quintela, Luis Angel; Barrio, Mónica; Becerra, Juan José; Peña, Ana Isabel; Vigo, Marcos; Garcia Herradon, Pedro

    2017-01-01

    The aim of this study was to describe the status of body condition score (BCS), hock injuries prevalence, locomotion and body hygiene score as animal welfare measures in 73 free-stall dairy cattle farms in Lugo (Spain). A benchmarking process was established across farms: (1) the animal-based indicators were ordered from low to high values; (2) The farms were classified into three categories based on the number of indicators within less than the 25th percentile, 25th to 75th percentile and above the 75th percentile. The median prevalence of unsuitable BCS, hock injuries and clinical lameness was (median (range)) 51.7 per cent (13.3 to 89.5 per cent), 40.0 per cent (7.0per cent to 100 per cent) and 9.0 per cent (0per cent to 60.0 per cent) respectively. The dirtiness of the cow’s coat had a high prevalence (73.0 per cent (37.5per cent to 100 per cent)). Most farms did not display consistently good or poor animal-based indicators and each farm had its own set of strong and weak points. Moreover, facilities design and management practices were described to understand source of the observations made of the cows. The incidence of overstocking was 31.5 per cent for stalls and 26.0 per cent for headlocks. The front lunge space was reduced (farms and they could benefit from others by changing management practices related to facilities and herds. PMID:29018530

  19. Reducing Respiratory Health Risks to Horses and Workers: A Comparison of Two Stall Bedding Materials

    Directory of Open Access Journals (Sweden)

    Markku Saastamoinen

    2015-10-01

    Full Text Available Stable air quality and the choice of bedding material are an important health issue both in horses and people working or visiting horse stables. Risks of impaired respiratory health are those that can especially be avoided by improving air quality in the stable. The choice of bedding material is particularly important in cold climate conditions; where horses are kept most of the day and year indoors throughout their life. This study examined the effect of two bedding materials; wood shavings and peat; on stable air quality and health of horses. Ammonia and dust levels were also measured to assess conditions in the stable. Ammonia was not detected or was at very low levels (<0.25 ppm in the boxes in which peat was used as bedding; but its concentration was clearly higher (1.5–7.0 ppm in stalls with wood shavings as bedding. Personal measurements of workers revealed quite high ammonia exposure (5.9 ppm8h in the boxes in which wood shavings were used; but no exposure was Animals 2015, 5 966 observed in stalls bedded with peat. The respiratory symptoms in horses increased regardless of the bedding material at the beginning of the study. The health status of the horses in the peat bedding group returned to the initial level in the end of the trial but horses bedded with wood shavings continued to be symptomatic. The hooves of the horses with peat bedding had a better moisture content than those of the horses bedded with wood shavings. The results suggest that peat is a better bedding material for horses than wood shavings regarding the health of both horses and stable workers.

  20. Climate trends account for stalled wheat yields in Australia since 1990.

    Science.gov (United States)

    Hochman, Zvi; Gobbett, David L; Horan, Heidi

    2017-05-01

    Global food security requires that grain yields continue to increase to 2050, yet yields have stalled in many developed countries. This disturbing trend has so far been only partially explained. Here, we show that wheat yields in Australia have stalled since 1990 and investigate the extent to which climate trends account for this observation. Based on simulation of 50 sites with quality weather data, that are representative of the agro-ecological zones and of soil types in the grain zone, we show that water-limited yield potential declined by 27% over a 26 year period from 1990 to 2015. We attribute this decline to reduced rainfall and to rising temperatures while the positive effect of elevated atmospheric CO 2 concentrations prevented a further 4% loss relative to 1990 yields. Closer investigation of three sites revealed the nature of the simulated response of water-limited yield to water availability, water stress and maximum temperatures. At all three sites, maximum temperature hastened time from sowing to flowering and to maturity and reduced grain number per m 2 and average weight per grain. This 27% climate-driven decline in water-limited yield is not fully expressed in actual national yields. This is due to an unprecedented rate of technology-driven gains closing the gap between actual and water-limited potential yields by 25 kg ha -1  yr -1 enabling relative yields to increase from 39% in 1990 to 55% in 2015. It remains to be seen whether technology can continue to maintain current yields, let alone increase them to those required by 2050. © 2017 John Wiley & Sons Ltd.

  1. Low-Order Modeling of Dynamic Stall on Airfoils in Incompressible Flow

    Science.gov (United States)

    Narsipur, Shreyas

    Unsteady aerodynamics has been a topic of research since the late 1930's and has increased in popularity among researchers studying dynamic stall in helicopters, insect/bird flight, micro air vehicles, wind-turbine aerodynamics, and ow-energy harvesting devices. Several experimental and computational studies have helped researchers gain a good understanding of the unsteady ow phenomena, but have proved to be expensive and time-intensive for rapid design and analysis purposes. Since the early 1970's, the push to develop low-order models to solve unsteady ow problems has resulted in several semi-empirical models capable of effectively analyzing unsteady aerodynamics in a fraction of the time required by high-order methods. However, due to the various complexities associated with time-dependent flows, several empirical constants and curve fits derived from existing experimental and computational results are required by the semi-empirical models to be an effective analysis tool. The aim of the current work is to develop a low-order model capable of simulating incompressible dynamic-stall type ow problems with a focus on accurately modeling the unsteady ow physics with the aim of reducing empirical dependencies. The lumped-vortex-element (LVE) algorithm is used as the baseline unsteady inviscid model to which augmentations are applied to model unsteady viscous effects. The current research is divided into two phases. The first phase focused on augmentations aimed at modeling pure unsteady trailing-edge boundary-layer separation and stall without leading-edge vortex (LEV) formation. The second phase is targeted at including LEV shedding capabilities to the LVE algorithm and combining with the trailing-edge separation model from phase one to realize a holistic, optimized, and robust low-order dynamic stall model. In phase one, initial augmentations to theory were focused on modeling the effects of steady trailing-edge separation by implementing a non-linear decambering

  2. Effect of stall design on dairy calf transition to voluntary feeding on an automatic milk feeder after introduction to group housing.

    Science.gov (United States)

    Wilson, Tanya R; LeBlanc, Stephen J; DeVries, Trevor J; Haley, Derek B

    2018-03-14

    Automatic milk feeders (AMF) for young dairy calves are widely used in the dairy industry. These feeders are thought to have benefits for calf health and welfare and may reduce labor required for feeding; however, little is known about how calves adapt to feeding with AMF. The objective of this study was to observe the effects of feeding stall design on calves learning to use the AMF. The hypothesis was that solid side stalls, compared with steel bar stalls, would result in a longer latency to approach and feed from the AMF without assistance. A total of 147 Holstein calves (80 male and 67 female) were enrolled at 4 d of age, introduced to a group pen, and, at the same time, trained on an AMF. For training, calves were allowed to suck on the trainer's fingers and guided to the teat. Calves were allocated to 1 of 2 stall designs at the pen level, depending on which treatment cohort they were born into, either with steel bar stall walls (n = 46 male, 34 female calves) or with solid side stall walls (n = 34 male, 33 female calves). For 72 h after introductory training on the AMF, data from the feeders were collected and calf behavior was monitored by video. Outcomes measured included latency to first voluntary visit to the feeder and to first feeding, time spent in the feeder, amount of milk consumed over 72 h, number of retraining sessions required (retrained if linear regression models or a Poisson model for the outcome of retraining. For certain outcomes the effects of stall design interacted with difficulty of training (willingness to enter feeder and drink); for the 38% of calves that were scored as moderately difficult to train on a scale of easy, moderate, or difficult, treatment (stall design) differences were detected. These calves took 2× longer to lick or bite toward the nipple, 2× longer to first voluntarily feeding, and consumed less milk over 72 h following training when trained on the steel bar stall design. These results suggest simple features of a

  3. Evaluation of Lower East Fork Poplar Creek Mercury Sources

    Energy Technology Data Exchange (ETDEWEB)

    Watson, David B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brooks, Scott C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mathews, Teresa J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevelhimer, Mark S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeRolph, Chris [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brandt, Craig C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peterson, Mark J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ketelle, Richard [East Tennessee Technology Park (ETTP), Oak Ridge, TN (United States)

    2016-06-01

    This report summarizes a 3-year research project undertaken to better understand the nature and magnitude of mercury (Hg) fluxes in East Fork Poplar Creek (EFPC). This project addresses the requirements of Action Plan 1 in the 2011 Oak Ridge Reservation-wide Comprehensive Environmental Response, Compensation, and Liability Act Five Year Review (FYR). The Action Plan is designed to address a twofold 2011 FYR issue: (1) new information suggests mobilization of mercury from the upper and lower EFPC streambeds and stream banks is the primary source of mercury export during high-flow conditions, and (2) the current Record of Decision did not address the entire hydrologic system and creek bank or creek bed sediments. To obtain a more robust watershed-scale understanding of mercury sources and processes in lower EFPC (LEFPC), new field and laboratory studies were coupled with existing data from multiple US Department of Energy programs to develop a dynamic watershed and bioaccumulation model. LEFPC field studies for the project focused primarily on quantification of streambank erosion and an evaluation of mercury dynamics in shallow groundwater adjacent to LEFPC and potential connection to the surface water. The approach to the stream bank study was innovative in using imagery from kayak floats’ surveys from the headwaters to the mouth of EFPC to estimate erosion, coupled with detailed bank soil mercury analyses. The goal of new field assessments and modeling was to generate a more holistic and quantitative understanding of the watershed and the sources, flux, concentration, transformation, and bioaccumulation of inorganic mercury (IHg) and methylmercury (MeHg). Model development used a hybrid approach that dynamically linked a spreadsheet-based physical and chemical watershed model to a systems dynamics, mercury bioaccumulation model for key fish species. The watershed model tracks total Hg and MeHg fluxes and concentrations by examining upstream inputs, floodplain

  4. Environmental Assessment - Construct a Ground-to-Air Transmitter and Receiver (GATR) Facility at Grand Forks Air Force Base

    National Research Council Canada - National Science Library

    2006-01-01

    ...) facility on Grand Forks Air Force Base (AFB), North Dakota. The Communication Squadron is preparing to install new GATR communication antennas and systems, for tactical aircraft control and commercial air traffic control...

  5. Environmental Assessment - Construct a Ground-to-Air Transmitter and Receiver (GATR) Facility at Grand Forks Air Force Base

    Science.gov (United States)

    2006-06-06

    crops include sugar beets, beans, corn, barley , and oats. The valley ranks first in the nation in the production of potatoes, spring wheat ...crops are spring wheat , barley , sunflowers, potatoes, and sugar beets. Turtle River State Park, developed as a recreation area in Grand Forks County...below the surface. Even though the Dakota Aquifer has produced more water than any other aquifer in Grand Forks County, the water is very saline and

  6. Mercury Content of Sediments in East Fork Poplar Creek: Current Assessment and Past Trends

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Scott C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Eller, Virginia A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dickson, Johnbull O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Earles, Jennifer E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lowe, Kenneth Alan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mehlhorn, Tonia L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Olsen, Todd A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeRolph, Christopher R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Watson, David J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Phillips, Debra H. [Queen' s Univ., Belfast (United Kingdom); Peterson, Mark J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-01-01

    This study provided new information on sediment mercury (Hg) and monomethylmercury (MMHg) content and chemistry. The current inventory of Hg in East Fork Poplar Creek (EFPC) bed sediments was estimated to be 334 kg, which represents a ~67% decrease relative to the initial investigations in 1984. MMHg sediment inventory was estimated to be 44.1 g, lower but roughly similar to past estimates. The results support the relevance and potential impacts of other active and planned investigations within the Mercury Remediation Technology Development for Lower East Fork Poplar Creek project (e.g., assessment and control of bank soil inputs, sorbents for Hg and MMHg removal, re-introduction of freshwater clams to EFPC), and identify gaps in current understanding that represent opportunities to understand controlling variables that may inform future technology development studies.

  7. Applications of the quartz tuning fork in classical and superfluid hydrodynamics

    Directory of Open Access Journals (Sweden)

    La Mantia Marco

    2012-04-01

    Full Text Available We present a short review of the multitude of applications of the commercially produced quartz tuning fork in cryogenic fluid dynamics, using cold gaseous, normal liquid and superfluid 4He as working fluids with extraordinary, but well-known and tunable physical properties. While the central focus of this work is the use of the tuning fork as a detector of classical and quantum turbulence, we also report other studies and applications, mainly on cavitation, pressure-, thermo- and viscosimetry. Finally, we mention briefly our recent studies of the acoustic emission due to these high-Q oscillators and its effect on the characteristics of their resonance.

  8. Turbo Charge CPU Utilization in Fork/Join Using the ManagedBlocker

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Fork/Join is a framework for parallelizing calculations using recursive decomposition, also called divide and conquer. These algorithms occasionally end up duplicating work, especially at the beginning of the run. We can reduce wasted CPU cycles by implementing a reserved caching scheme. Before a task starts its calculation, it tries to reserve an entry in the shared map. If it is successful, it immediately begins. If not, it blocks until the other thread has finished its calculation. Unfortunately this might result in a significant number of blocked threads, decreasing CPU utilization. In this talk we will demonstrate this issue and offer a solution in the form of the ManagedBlocker. Combined with the Fork/Join, it can keep parallelism at the desired level.

  9. An Archeological Survey in the Gypsum Breaks on the Elm Fork of the Red River,

    Science.gov (United States)

    1979-01-01

    respectively). Further south running along the Red River and the Brazos River in northern Texas is the Henrietta Focus. The Harrell site near the con...fluence of the Brazos and the Clear Fork rivers is the type site for this association. The Henrietta Focus occurred about the same time as *the...De Soto expedition in 1541 suffered from a lack of salt supplies and persuaded Indians to lead them to some natural salt deposits in northeastern

  10. Environmental Assessment: Demolish Buildings 212, 218, 819, 820 at Grand Forks Air Force Base

    Science.gov (United States)

    2007-01-31

    land used for pasture and hay, urban development, recreation, and wildlife habitat. Principal crops are spring wheat , barley , sunflowers, potatoes...though the Dakota Aquifer has produced more water than any other aquifer in Grand Forks County, the water is very saline and generally unsatisfactory for...can contribute to violations of water quality standards. During low flow periods, the rivers are generally too saline for domestic use. Grand

  11. Environmental Assessment: Construct a CDC Main Entry Addition at Grand Forks Air Force Base

    Science.gov (United States)

    2006-03-01

    beans, corn, barley , and oats. The valley ranks first in the nation in the production of potatoes, spring wheat , sunflowers, and durum wheat ...recreation, and wildlife habitat. Principal crops are spring wheat , barley , sunflowers, potatoes, and sugar beets. Turtle River State Park...though the Dakota Aquifer has produced more water than any other aquifer in Grand Forks County, the water is very saline and generally

  12. Environmental Assessment: Construct Airfield Lighting Vault and Demolish Building 531 at Grand Forks Air Force Base

    Science.gov (United States)

    2007-08-01

    beans, corn, barley , and oats. The valley ranks first in the nation in the production of potatoes, spring wheat , sunflowers, and durum wheat . Grand...with remaining land used for pasture and hay, urban development, recreation, and wildlife habitat. Principal crops are spring wheat , barley ...surface. Even though the Dakota Aquifer has produced more water than any other aquifer in Grand Forks County, the water is very saline and generally

  13. Environmental Assessment, Demolition of Alpha Ramp Grand Forks Air Force Base, North Dakota

    Science.gov (United States)

    2007-01-01

    January 2004). 3.10 Land Use Land use in Grand Forks County consists primarily of cultivated crops, including spring wheat , barley , sunflowers...surveyed acres fully support swimming. Conversely, groundwater quality surrounding GFAFB is variable. Due to generally high salinity , groundwater from the...Dakota Aquifer is unusable for domestic or industrial purposes. Portions of the Dakota and Pierre aquifers with lower salinity are used for

  14. On cavitation in liquid helium in a flow due to a vibrating quartz fork

    Czech Academy of Sciences Publication Activity Database

    Blažková, Michaela; Schmoranzer, D.; Skrbek, Ladislav

    2008-01-01

    Roč. 34, 4/5 (2008), s. 298-307 ISSN 1063-777X R&D Projects: GA ČR GA202/05/0218 Grant - others:GAUK(CZ) 7953/2007 Institutional research plan: CEZ:AV0Z10100520 Keywords : cavitation * He I * He II * quartz tuning fork Subject RIV: BK - Fluid Dynamics Impact factor: 0.780, year: 2008

  15. Cavitation in liquid helium observed in a flow due to a vibrating quartz fork

    Czech Academy of Sciences Publication Activity Database

    Blažková, Michaela; Chagovets, Tymofiy; Rotter, M.; Schmoranzer, D.; Skrbek, L.

    2008-01-01

    Roč. 150, 3-4 (2008), s. 194-199 ISSN 0022-2291 R&D Projects: GA ČR GA202/05/0218 Grant - others:GAUK(CZ) 7953/2007 Institutional research plan: CEZ:AV0Z10100520 Keywords : cavitation * He I * He II * quartz tuning fork Subject RIV: BK - Fluid Dynamics Impact factor: 1.034, year: 2008

  16. NDA measurements on spent fuel assemblies at Tihange 1 by means of the ION 1/FORK

    International Nuclear Information System (INIS)

    Carchon, R.; Smaers, G.; Verrecchia, G.P.D.; Arlt, R.; Stoyanova, I.; Satinet, J.

    1986-06-01

    This report describes field tests performed at Tihange 1 Nuclear Power Station on PWR spent fuel by means of the ION 1-FORK detector. Two detector systems and three electronics systems were used to investigate the same fuel assemblies with various burn-ups and cooling times. The purpose of the exercise was to test the performance of the instrument for as well inspection purposes as for fuel management. The results are presented and discussed. (Author)

  17. Temperature, Frequency, and Young’s Modulus of an Aluminum Tuning Fork

    Directory of Open Access Journals (Sweden)

    Zachery L. Greer

    2011-01-01

    Full Text Available The frequency produced by a standard C (523.3 Hz aluminum alloy tuning fork when struck at temperatures ranging from 29 ̊C to 300 ̊C was studied. It was found that frequency decreased with increasing temperature with an inverse exponential relationship. The frequency was used to calculate Young’s Modulus for aluminum, with the results being in close agreement with published values.

  18. Testování knihovny fork/join v jazyce Java 7

    OpenAIRE

    MAXA, Karel

    2012-01-01

    In release Java 7 comes new library fork/join from package java.util.concurrent, which help to better usage of parralel architecture and thus bring more time effective applications. The bachelor is aimed at describe and make recommendation for usage of this library. Main part of bachelor is aimed at implementation tests and their evalution for showing time efficiency. For the test was written program in Java, which was executed on different system platforms and different hardware architectures.

  19. Slow Replication Fork Velocity of Homologous Recombination-Defective Cells Results from Endogenous Oxidative Stress

    Science.gov (United States)

    Magdalou, Indiana; Machon, Christelle; Dardillac, Elodie; Técher, Hervé; Guitton, Jérôme; Debatisse, Michelle; Lopez, Bernard S.

    2016-01-01

    Replications forks are routinely hindered by different endogenous stresses. Because homologous recombination plays a pivotal role in the reactivation of arrested replication forks, defects in homologous recombination reveal the initial endogenous stress(es). Homologous recombination-defective cells consistently exhibit a spontaneously reduced replication speed, leading to mitotic extra centrosomes. Here, we identify oxidative stress as a major endogenous source of replication speed deceleration in homologous recombination-defective cells. The treatment of homologous recombination-defective cells with the antioxidant N-acetyl-cysteine or the maintenance of the cells at low O2 levels (3%) rescues both the replication fork speed, as monitored by single-molecule analysis (molecular combing), and the associated mitotic extra centrosome frequency. Reciprocally, the exposure of wild-type cells to H2O2 reduces the replication fork speed and generates mitotic extra centrosomes. Supplying deoxynucleotide precursors to H2O2-exposed cells rescued the replication speed. Remarkably, treatment with N-acetyl-cysteine strongly expanded the nucleotide pool, accounting for the replication speed rescue. Remarkably, homologous recombination-defective cells exhibit a high level of endogenous reactive oxygen species. Consistently, homologous recombination-defective cells accumulate spontaneous γH2AX or XRCC1 foci that are abolished by treatment with N-acetyl-cysteine or maintenance at 3% O2. Finally, oxidative stress stimulated homologous recombination, which is suppressed by supplying deoxynucleotide precursors. Therefore, the cellular redox status strongly impacts genome duplication and transmission. Oxidative stress should generate replication stress through different mechanisms, including DNA damage and nucleotide pool imbalance. These data highlight the intricacy of endogenous replication and oxidative stresses, which are both evoked during tumorigenesis and senescence initiation

  20. On Bandwidth Characteristics of Tuning Fork Micro-Gyroscope with Mechanically Coupled Sense Mode

    Directory of Open Access Journals (Sweden)

    Yunfang Ni

    2014-07-01

    Full Text Available The bandwidth characteristics of a tuning fork micro-gyroscope with mechanically coupled sense mode were investigated in this paper to provide some references for mechanical bandwidth design. The concept of sense mode mechanical coupling is introduced first. Theoretical frequency response analyses were then carried out on the mechanical part of the gyroscope. Equations representing the relationships between the differential output signal and the frequency of the input angular rate were deduced in full frequency range and further simplified in low frequency range. Based on these equations, bandwidth characteristics under ideal and non-ideal conditions are discussed. Analytical results show that under ideal conditions, the bandwidth characteristics of a tuning fork micro-gyroscope are similar to those of a single mass micro-gyroscope, but under non-ideal conditions, especially when sense mass and/or stiffness are asymmetric, the bandwidth characteristics would be quite different because the in-phase mode would participate in the anti-phase vibration response. Experimental verifications were carried out on two micro-gyroscope prototypes designed in our laboratory. The deduced equations and analytical results can be used in guiding the mechanical bandwidth design of tuning fork micro-gyroscopes with mechanically coupled sense mode.

  1. Vibration Study of Fork-lift Truck Based on the Virtual Prototype Technology

    Directory of Open Access Journals (Sweden)

    YANG Mingliang

    2014-05-01

    Full Text Available The forklift truck is one of important equipments of the modern logistics system. As the forklift truck is running, the driver seat and steering wheel of a certain type of fork-lift truck vibrate strongly, virtual prototyping technology and multi-body dynamics are used to make simulation of dynamic performance of fork-lift truck in this paper, and then the test result is compared with time course load that obtained from frame junction with the annex. We should repeatedly modify the simulation model based on test results, which is consistent with the actual results. Based on this model, so we put forward measures for improving design: Firstly, the axis of rotation of oval steering axle is implied; Secondly, the overhead guard is connected with the frame by the rubber cushion blocks at four different locations; Thirdly, the engine is fixed on the frame by the rubber cushion blocks (shock mount in two different position. The improved simulation and experimental verification are carried out under the same conditions, and the results show that the fundamental frequency of seat of the improved fork-lift truck and vibration energy are lower. The result proves the practical value of this method in the research of the vibration characteristics of complete engineering machine.

  2. A tip-attached tuning fork sensor for the control of DNA translocation through a nanopore.

    Science.gov (United States)

    Hyun, Changbae; Kaur, Harpreet; Huang, Tao; Li, Jiali

    2017-02-01

    In this work, we demonstrate that a tuning fork can be used as a force detecting sensor for manipulating DNA molecules and for controlling the DNA translocation rate through a nanopore. One prong of a tuning fork is glued with a probe tip which DNA molecules can be attached to. To control the motion and position of the tip, the tuning fork is fixed to a nanopositioning system which has sub-nanometer position control. A fluidic chamber is designed to fulfill many requirements for the experiment: for the access of a DNA-attached tip approaching to a nanopore, for housing a nanopore chip, and for measuring ionic current through a solid-state nanopore with a pair of electrodes. The location of a nanopore is first observed by transmission electron microscopy, and then is determined inside the liquid chambers with an optical microscope combined with local scanning the probe tip on the nanopore surface. When a DNA-immobilized tip approaches a membrane surface near a nanopore, free ends of the immobilized DNA strings can be pulled and trapped into the pore by an applied voltage across the nanopore chip, resulting in an ionic current reduction through the nanopore. The trapped DNA molecules can be lifted up from the nanopore at a user controlled speed. This integrated apparatus allows manipulation of biomolecules (DNA, RNA, and proteins) attached to a probe tip with sub-nanometer precision, and simultaneously allows measurement of the biomolecules by a nanopore device.

  3. The progression of replication forks at natural replication barriers in live bacteria.

    Science.gov (United States)

    Moolman, M Charl; Tiruvadi Krishnan, Sriram; Kerssemakers, Jacob W J; de Leeuw, Roy; Lorent, Vincent; Sherratt, David J; Dekker, Nynke H

    2016-07-27

    Protein-DNA complexes are one of the principal barriers the replisome encounters during replication. One such barrier is the Tus-ter complex, which is a direction dependent barrier for replication fork progression. The details concerning the dynamics of the replisome when encountering these Tus-ter barriers in the cell are poorly understood. By performing quantitative fluorescence microscopy with microfuidics, we investigate the effect on the replisome when encountering these barriers in live Escherichia coli cells. We make use of an E. coli variant that includes only an ectopic origin of replication that is positioned such that one of the two replisomes encounters a Tus-ter barrier before the other replisome. This enables us to single out the effect of encountering a Tus-ter roadblock on an individual replisome. We demonstrate that the replisome remains stably bound after encountering a Tus-ter complex from the non-permissive direction. Furthermore, the replisome is only transiently blocked, and continues replication beyond the barrier. Additionally, we demonstrate that these barriers affect sister chromosome segregation by visualizing specific chromosomal loci in the presence and absence of the Tus protein. These observations demonstrate the resilience of the replication fork to natural barriers and the sensitivity of chromosome alignment to fork progression. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. Has Uganda experienced any stalled fertility transitions? Reflecting on the last four decades (1973-2011).

    Science.gov (United States)

    Kabagenyi, Allen; Reid, Alice; Rutaremwa, Gideon; Atuyambe, Lynn M; Ntozi, James P M

    2015-09-23

    Persistent high fertility is associated with mother and child mortality. While most regions in the world have experienced declines in fertility rates, there are conflicting views as to whether Uganda has entered a period of fertility transition. There are limited data available that explicitly detail the fertility trends and patterns in Uganda over the last four decades, from 1973 to 2011. Total fertility rate (TFR) is number of live births that a woman would have throughout her reproductive years if she were subject to the prevailing age specific fertility patterns. The current TFR for Uganda stands at 6.2 children born per woman, which is one of the highest in the region. This study therefore sought to examine whether there has been a fertility stall in Uganda using all existing Demographic Health Survey data, to provide estimates for the current fertility levels and trends in Uganda, and finally to examine the demographic and socioeconomic factors responsible for fertility levels in Uganda. This is a secondary analysis of data from five consecutive Ugandan Demographic Health Surveys (UDHS); 1988/1989, 1995, 2000/2001, 2006 and 2011. Using pooled data to estimate for fertility levels, patterns and trends, we applied a recently developed fertility estimation approach. A Poisson regression model was also used to analyze fertility differentials over the study period. Over the studied period, fertility trends and levels fluctuated from highs of 8.8 to lows of 5.7, with no specific lag over the study period. These findings suggest Uganda is at the pre-transitional stage, with indications of imminent fertility rate reductions in forthcoming years. Marital status remained a strong predictor for number of children born, even after controlling for other variables. This study suggests there is no evidence of a fertility stall in Uganda, but demonstrates an onset of fertility transition in the country. If this trend continues, Uganda will experience a low fertility rate in

  5. Design of a 21 m blade with Risø-A1 airfoils for active stall controlled wind turbines

    DEFF Research Database (Denmark)

    Fuglsang, Peter; Sangill, O.; Hansen, P.

    2002-01-01

    This is the final report, from the project, "Design of a Rotor/Airfoil Family for Active Stall-regulated Wind Turbines by Use of Multi-point Optimization". It describes the full scale testing of a 21 m wind turbine blade specially designed for active stallregulation. Design objectives were...... increased ratio of produced energy to turbine loads and more stable power control characteristics. Both were taken directly into account during the design of the blade using numerical optimization. The blade used theRisø-A1 airfoil family, which was specially designed for operation on wind turbine blades...... be concluded that the new LM 21.0 ASR blade could replace the LM 21.0P leading to improved cost efficiency and that the Risø-A1 airfoils were well suited for active stall control. With the newestablished knowledge of the actual airfoil characteristics, a possible future blade design could be made also...

  6. Experimental investigation of flow-induced vibration of a pitch-plunge NACA 0015 airfoil under deep dynamic stall

    Czech Academy of Sciences Publication Activity Database

    Šidlof, Petr; Vlček, Václav; Štěpán, M.

    2016-01-01

    Roč. 67, November (2016), s. 48-59 ISSN 0889-9746 R&D Projects: GA ČR GA13-10527S Institutional support: RVO:61388998 Keywords : NACA 0015 airfoil * aeroelasticity * stall flutter * dynamic stall * limit cycle oscillation * schlieren Subject RIV: BI - Acoustics Impact factor: 2.021, year: 2016 http://ac.els-cdn.com/S0889974615300724/1-s2.0-S0889974615300724-main.pdf?_tid=31f9fa5a-d1c0-11e6-a705-00000aab0f26&acdnat=1483453588_64a6e8b2119c9afad3639cdec32a4569

  7. Advance Ratio Effects on the Dynamic-stall Vortex of a Rotating Blade in Steady Forward Flight

    Science.gov (United States)

    2014-08-06

    of the wind tunnel and is illustrated in Fig. 1. In order to simplify the operations, a two-bladed rotor design was preferred. The setup had manually...to wind turbines, compressors, helicopter rotors , and even insect wing aerodynamics. Dynamic stall occurs on rotating blades of a helicopter in forward...between the flow structure on helicopter rotor blades, wind turbine blades, and insect wings. Due to these wide engineering implications there has

  8. Parametric analyses for synthetic jet control on separation and stall over rotor airfoil

    Directory of Open Access Journals (Sweden)

    Zhao Guoqing

    2014-10-01

    Full Text Available Numerical simulations are performed to investigate the effects of synthetic jet control on separation and stall over rotor airfoils. The preconditioned and unsteady Reynolds-averaged Navier–Stokes equations coupled with a k − ω shear stream transport turbulence model are employed to accomplish the flowfield simulation of rotor airfoils under jet control. Additionally, a velocity boundary condition modeled by a sinusoidal function is developed to fulfill the perturbation effect of periodic jets. The validity of the present CFD procedure is evaluated by the simulated results of an isolated synthetic jet and the jet control case for airfoil NACA0015. Then, parametric analyses are conducted specifically for an OA213 rotor airfoil to investigate the effects of jet parameters (forcing frequency, jet location and momentum coefficient, jet direction, and distribution of jet arrays on the control effect of the aerodynamic characteristics of a rotor airfoil. Preliminary results indicate that the efficiency of jet control can be improved with specific frequencies (the best lift-drag ratio at F+ = 2.0 and jet angles (40° or 75° when the jets are located near the separation point of the rotor airfoil. Furthermore, as a result of a suitable combination of jet arrays, the lift coefficient of the airfoil can be improved by nearly 100%, and the corresponding drag coefficient decreased by 26.5% in comparison with the single point control case.

  9. Analysis of the grid connection sequence of stall- and pitch-controlled wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Quinonez-Varela, G.; Cruden, A.; Anaya-Lara, O.; Tumilty, R.; McDonald, J.R. [Univ. of Strathclyde, Inst. for Energy and Environment (United Kingdom)

    2007-11-15

    The realistic modelling of wind turbines and wind farms is crucial in any form of power system analysis, and consequently, knowledge about their electrical characteristics and performance is also vital. One of the operating conditions producing major transient interaction between a wind turbine generator and the local grid is the grid connection sequence itself, which is particularly significant in fixed-speed turbines. This paper presents experimental measurements of the grid connection sequence of both types of fixed speed wind turbines, i.e. stall- and pitch-controlled via a soft-start device performed at two existing wind farms. Some of the results evidenced significant discrepancies between the actual soft-start operating intervals and those stated/suggested by open literature. The discussion of the paper focuses on highlighting the importance of accurate modelling of the grid connection sequence in order to avoid erroneous estimations of the interaction between the turbine and the grid during this operating state, or inappropriate design of the grid connection. (au)

  10. Why commercialization of gene therapy stalled; examining the life cycles of gene therapy technologies.

    Science.gov (United States)

    Ledley, F D; McNamee, L M; Uzdil, V; Morgan, I W

    2014-02-01

    This report examines the commercialization of gene therapy in the context of innovation theories that posit a relationship between the maturation of a technology through its life cycle and prospects for successful product development. We show that the field of gene therapy has matured steadily since the 1980s, with the congruent accumulation of >35 000 papers, >16 000 US patents, >1800 clinical trials and >$4.3 billion in capital investment in gene therapy companies. Gene therapy technologies comprise a series of dissimilar approaches for gene delivery, each of which has introduced a distinct product architecture. Using bibliometric methods, we quantify the maturation of each technology through a characteristic life cycle S-curve, from a Nascent stage, through a Growing stage of exponential advance, toward an Established stage and projected limit. Capital investment in gene therapy is shown to have occurred predominantly in Nascent stage technologies and to be negatively correlated with maturity. Gene therapy technologies are now achieving the level of maturity that innovation research and biotechnology experience suggest may be requisite for efficient product development. Asynchrony between the maturation of gene therapy technologies and capital investment in development-focused business models may have stalled the commercialization of gene therapy.

  11. Flow-around modes for a rhomboid wing with a stall vortex in the shock layer

    Science.gov (United States)

    Zubin, M. A.; Maximov, F. A.; Ostapenko, N. A.

    2017-12-01

    The results of theoretical and experimental investigation of an asymmetrical hypersonic flow around a V-shaped wing with the opening angle larger than π on the modes with attached shockwaves on forward edges, when the stall flow is implemented on the leeward wing cantilever behind the kink point of the cross contour. In this case, a vortex of nonviscous nature is formed in which the velocities on the sphere exceeding the speed of sound and resulting in the occurrence of pressure shocks with an intensity sufficient for the separation of the turbulent boundary layer take place in the reverse flow according to the calculations within the framework of the ideal gas. It is experimentally established that a separation boundary layer can exist in the reverse flow, and its structure is subject to the laws inherent to the reverse flow in the separation region of the turbulent boundary layer arising in the supersonic conic flow under the action of a shockwave incident to the boundary layer.

  12. Exploring farmers’ seasonal and full year adoption of stall feeding of livestock in Tigrai region, Ethiopia

    Directory of Open Access Journals (Sweden)

    Hadush Muuz

    2017-01-01

    Full Text Available Adoption of stall feeding (SF of livestock was assessed in northern Ethiopia based on a household survey conducted in 2015. The study covered 21 communities in Tigrai to account for differences in agroecology. The purpose of this study was to understand the driving factors of full or seasonal SF adoption and its intensity. A Heckman selection model was used to estimate adoption and extent of adoption based on a model of technology adoption within an agricultural household framework, and Poisson Model for explaining the number of SF adopting seasons. The descriptive results indicate that 36% of the farmers were actually practicing SF in a full year whereas 55.6% were seasonal adopters in the study area. Empirical results of this study showed that our result is in favor of the Boserupian hypothesis indicating that small grazing land and large exclosure are associated with a higher probability of use of SF and with a higher number of SF adopting seasons. In a similar vein, small average village farm size stimulated SF adoption and adopting seasons, Availability of labor and a number of breed cows significantly increased the probability of using SF by 0.01% and 66% respectively. While animal shock had a marginal effect of 14%, factors such as access to information and early exposure increased SF adoption by about 18% and 6%. Similarly, the positive marginal effect of real milk price is 15%. However, SF appears to be less attractive to those farmers with more herd size and less crop residue.

  13. Transonic Wind Tunnel Modernization for Experimental Investigation of Dynamic Stall in a Wide Range of Mach Numbers by Plasma Actuators with Combined Energy/Momentum Action

    Science.gov (United States)

    2015-01-02

    wind tunnel for the study of plasma based methods for the control of dynamic stall for helicopter rotor blades. The tunnel has a 3D positioning...SECURITY CLASSIFICATION OF: This equipment grant supported the design and construction of a subsonic variable speed wind tunnel for the study of...plasma based methods for the control of dynamic stall for helicopter rotor blades. The tunnel has a 3D positioning system and servomotor mounted below

  14. Hydrology of the North Fork of the Right Fork of Miller Creek, Carbon County, Utah, before, during, and after underground coal mining

    Science.gov (United States)

    Slaughter, C.B.; Freethey, G.W.; Spangler, L.E.

    1995-01-01

    From 1988-92 the U.S. Geological Survey, in cooperation with the Utah Division of Oil, Gas, and Mining, studied the effects of underground coal mining and the resulting subsidence on the hydrologic system near the North Fork of the Right Fork of Miller Creek, Carbon County, Utah. The subsidence caused open fractures at land surface, debris slides, and rockfalls in the canyon above the mined area. Land surface subsided and moved several feet horizontally. The perennial stream and a tributary upstream from the mined area were diverted below the ground by surface fractures where the overburden thickness above the Wattis coal seam is 300 to 500 feet. The reach downstream was dry but flow resumed where the channel traversed the Star Point Sandstone, which forms the aquifer below the coal seams where ground-water discharge provides new base flow. Concentrations of dissolved constituents in the stream water sampled just downstream from the mined area increased from about 300 mg/L (milligrams per liter) to more than 1,500 mg/L, and the water changed from primarily a magnesium calcium bicarbonate to primarily a magnesium sulfate type. Monitored water levels in two wells completed in the perched aquifer(s) above the mine indicate that fractures from subsidence- related deformation drained the perched aquifer in the Blackhawk Formation. The deformation also could have contributed to the decrease in discharge of three springs above the mined area, but discharge from other springs in the area did not change ubstantially; thus, the relation between subsidence and spring discharge, if any, is not clear. No significant changes in the chemical character of water discharging from springs were detected, but the dissolved-solids concentration in water collected from a perched sandstone aquifer overlying the mined coal seams increased during mining activity.

  15. Evaluation of free-stall mattress bedding treatments to reduce mastitis bacterial growth

    Energy Technology Data Exchange (ETDEWEB)

    Kristula, M.A.; Dou, Z.; Toth, J.D.; Smith, B.I.; Harvey, N.; Sabo, M. [University of Penn, Kennett Square, PA (United States)

    2008-05-15

    Bacterial counts were compared in free-stall mattresses and teat ends exposed to 5 treatments in a factorial study design on 1 dairy farm. Mattresses in five 30-cow groups were subjected to 1 of 5 bedding treatments every other day: 0.5 kg of hydrated limestone, 120 mL of commercial acidic conditioner, 1 kg of coal fly ash, 1 kg of kiln-dried wood shavings, and control (no bedding). Counts of coliforms, Klebsiella spp., Escherichia coli, and Streptococcus spp. were lowest on mattresses bedded with lime. Mattresses bedded with the commercial acidic conditioner had the next lowest counts for coliforms, Klebsiella spp., and Streptococcus spp. Wood shavings and the no-bedding control had the highest counts for coliform and Klebsiella spp. Compared with wood shavings or control, fly ash reduced the counts of coliforms, whereas for the other 3 bacterial groups, the reduction was not always significant. Streptococcus spp. counts were greatest in the control group and did not differ among the shavings and fly ash groups. Teat swab results indicated that hydrated lime was the only bedding treatment that significantly decreased the counts of both coliforms and Klebsiella spp. There were no differences in Streptococcus spp. numbers on the teats between any of the bedding treatments. Bacterial populations grew steadily on mattresses and were generally higher at 36 to 48 h than at 12 to 24 h, whereas bacterial populations on teats grew rapidly by 12 h and then remained constant. Hydrated lime was the only treatment that significantly reduced bacterial counts on both mattresses and teat ends, but it caused some skin irritation.

  16. Evaluation of rice mutant lines for resistance to brown planthopper, nilaparvata lugens stall

    International Nuclear Information System (INIS)

    Mugiono

    1985-01-01

    The most important and common insect in rice cultivation in South East Asia is brown planthopper, nilaparvata lugens stall. Seven rice mutant lines produced by the National Atomic Energy Agency, Indonesia, were tested at IRRI, the Philippines for resistance to brown planthopper. Those mutant lines were Atomita 1, 627/10-3/PsJ, Atomita 2 and 627/4-E/PsJ originated from Pelita 1/1 which was irradiated with 0.2 kGy of gamma rays and A227/2/PsJ, A227/3/PsJ and A227/5/PsJ, originated from early maturing mutant A23/PsJ/72K from irradiated Pelita 1/1 which was irradiated with 0.1 kGy of gamma rays. Evaluation of resistance was carried out by seedling bulk screening, honeydew excretion, survival and population build up tests by using brown planthopper biotype 1, 2 and 3. Results of these tests showed that the seven tested mutant lines were resistant to biotype 1 but susceptible to biotype 2. Reaction to biotype 3 showed that six mutant lines tested were moderately resistant and only one mutant of 627/4-E/PsJ was susceptible. Reactions of the mutant lines to biotype 1, 2 and 3 were different from the resistant varieties, Mudgo or ASD-7. This indicated that mutant lines might have gene(s) for resistance which differed from those of resistant varieties. The results showed that resistance to brown planthopper is possible to be introduced in Indonesian rice varieties by means of mutations. (author)

  17. Stalled repair of lesions when present within a clustered DNA damage site

    International Nuclear Information System (INIS)

    Lomax, M.E.; Cunniffe, S.; O'Neill, P.

    2003-01-01

    Ionising radiation produces clustered DNA damages (two or more lesions within one or two helical turns of the DNA) which could challenge the repair mechanism(s) of the cell. Using purified base excision repair (BER) enzymes and synthetic oligonucleotides a number of recent studies have established the excision of a lesion within clustered damage sites is compromised. Evidence will be presented that the efficiency of repair of lesions within a clustered DNA damage site is reduced, relative to that of the isolated lesions, since the lifetime of both lesions is extended by up to four fold. Simple clustered damage sites, comprised of single-strand breaks, abasic sites and base damages, one or five bases 3' or 5' to each other, were synthesised in oligonucleotides and repair carried out in mammalian cell nuclear extracts. The rate of repair of the single-strand break/abasic site within these clustered damage sites is reduced, mainly due to inhibition of the DNA ligase. The mechanism of repair of the single-strand break/abasic site shows some asymmetry. Repair appears to be by the short-patch BER pathway when the lesions are 5' to each other. In contrast, when the lesions are 3' to each other repair appears to proceed along the long-patch BER pathway. The lesions within the cluster are processed sequentially, the single-strand break/abasic site being repaired before excision of 8-oxoG, limiting the formation of double-strand breaks to <2%. Stalled processing of clustered DNA damage extends the lifetime of the lesions to an extent that could have biological consequences, e.g. if the lesions are still present during transcription and/or at replication mutations could arise

  18. Mercury and other Mining-Related Contaminants in Ospreys along the Upper Clark Fork River, MT

    Science.gov (United States)

    Langner, H.; Domenech, R.; Greene, E.; Staats, M. F.

    2010-12-01

    Osprey (Pandion haliaetus) are widely recognized as bio-indicators of the health of aquatic ecosystems. Until the time of fledging, nestlings feed exclusively on fish caught within a few kilometers of the nest. Therefore, tissues of these young birds may reflect the level of contamination of local fish and more generally, the contamination status of the aquatic ecosystem they inhabit. Nests can often be accessed with a boom truck and obtaining small blood samples from the flightless chicks is fairly noninvasive. Ospreys are nesting along the Upper Clark Fork River, Montana, which is heavily contaminated with wastes left from a century of copper and precious metals mining. We have been monitoring the levels of priority pollutants (arsenic, cadmium, lead, copper, zinc, mercury and selenium) in Osprey chicks along a 250 km section of the river for four years. Objectives are to establish current contaminant status, pinpoint pollution hotspots, and assess the success of restoration efforts. Our results suggest that of highest concern may be the bioaccumulation of mercury with blood levels of up to 0.7 mg/L in the growing chicks. These concentrations are expected to increase many fold upon fledging as feather growth stops, which acts as the major sink for mercury. Interestingly, we found mercury levels increased in downstream direction, in contrast to concentrations of other pollutants. Reasons may be the different origin of mercury versus other contaminants and the distribution of wetlands where mercury can be transformed into highly bioavailable methylmercury. Blood levels of selenium are also elevated throughout the Upper Clark Fork River drainage. We discuss the implications for restoration and remediation of the Clark Fork River.

  19. In-Field Performance Testing of the Fork Detector for Quantitative Spent Fuel Verification

    Energy Technology Data Exchange (ETDEWEB)

    Gauld, Ian C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hu, Jianwei [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); De Baere, P. [European Commission (Luxembourg). DG Energy, Directorate Nuclear Safeguards; Vaccaro, S. [European Commission (Luxembourg). DG Energy, Directorate Nuclear Safeguards; Schwalbach, P. [European Commission (Luxembourg). DG Energy, Directorate Nuclear Safeguards; Liljenfeldt, Henrik [Swedish Nuclear Fuel and Waste Management Company (Sweden); Tobin, Stephen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-01-01

    Expanding spent fuel dry storage activities worldwide are increasing demands on safeguards authorities that perform inspections. The European Atomic Energy Community (EURATOM) and the International Atomic Energy Agency (IAEA) require measurements to verify declarations when spent fuel is transferred to difficult-to-access locations, such as dry storage casks and the repositories planned in Finland and Sweden. EURATOM makes routine use of the Fork detector to obtain gross gamma and total neutron measurements during spent fuel inspections. Data analysis is performed by modules in the integrated Review and Analysis Program (iRAP) software, developed jointly by EURATOM and the IAEA. Under the framework of the US Department of Energy–EURATOM cooperation agreement, a module for automated Fork detector data analysis has been developed by Oak Ridge National Laboratory (ORNL) using the ORIGEN code from the SCALE code system and implemented in iRAP. EURATOM and ORNL recently performed measurements on 30 spent fuel assemblies at the Swedish Central Interim Storage Facility for Spent Nuclear Fuel (Clab), operated by the Swedish Nuclear Fuel and Waste Management Company (SKB). The measured assemblies represent a broad range of fuel characteristics. Neutron count rates for 15 measured pressurized water reactor assemblies are predicted with an average relative standard deviation of 4.6%, and gamma signals are predicted on average within 2.6% of the measurement. The 15 measured boiling water reactor assemblies exhibit slightly larger deviations of 5.2% for the gamma signals and 5.7% for the neutron count rates, compared to measurements. These findings suggest that with improved analysis of the measurement data, existing instruments can provide increased verification of operator declarations of the spent fuel and thereby also provide greater ability to confirm integrity of an assembly. These results support the application of the Fork detector as a fully quantitative spent fuel

  20. Geomorphic Change Induced by 100 years of Flow Alteration on the Diamond Fork River, Central Utah

    Science.gov (United States)

    Jones, J.; Belmont, P.; Wilcock, P. R.

    2017-12-01

    Changes in hydrology and sediment supply affect the form of rivers. The rate of change of fluvial form is controlled by a variety of factors, including valley confinement, sediment size, and antecedent condition. The Diamond Fork River in central Utah has been altered by trans-basin flows delivered from the Colorado River system for over a century. Beginning in 1915, water used for irrigation was delivered through a tributary, Sixth Water Creek, with daily summer flows regularly exceeding the 50 - 100 year flood. Elevated flows caused drastic geomorphic change - resulting in incision and widening of the channel, and the destruction of riparian vegetation. Beginning in 1997, the outlet for the trans-basin diversion was moved downstream on Sixth Water, bypassing a large landslide, and flows were drastically reduced in 2004 through management actions. We delineated eight distinct process domains for the Sixth Water-Diamond Fork system and examined the response of each process domain to the altered flow and sediment regimes through the analysis of aerial photographs and repeat cross-sections. We measured a variety of channel metrics, including channel width, areal extent of bars and islands, and sinuosity in ArcGIS. Results indicate that unconfined reaches that were wide and braided during the period of elevated flows have narrowed to become single threaded and meandering in response to the reduced flows. Confined reaches have experienced minor changes since the reduction in flows, suggesting that confinement is a primary control on the degree of channel response. These findings and complimentary studies will provide managers of Sixth Water and Diamond Fork with a greater understanding of the physical response of the streams, and the resulting effects on ecological communities.

  1. Best management practices plan for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-04-01

    This plan was prepared in support of the Phase II Remedial Design Report (DOE/OR/01-1449 ampersand D1) and in accordance with requirements under CERCLA to present the plan for best management practices to be followed during the remediation. This document provides the Environmental Restoration Program with information about spill prevention and control, water quality monitoring, good housekeeping practices, sediment and erosion control measures, and inspections and environmental compliance practices to be used during Phase II of the remediation project for the Lower East Fork Poplar Creek Operable Unit

  2. Best management practices plan for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    This plan was prepared in support of the Phase II Remedial Design Report (DOE/OR/01-1449&D1) and in accordance with requirements under CERCLA to present the plan for best management practices to be followed during the remediation. This document provides the Environmental Restoration Program with information about spill prevention and control, water quality monitoring, good housekeeping practices, sediment and erosion control measures, and inspections and environmental compliance practices to be used during Phase II of the remediation project for the Lower East Fork Poplar Creek Operable Unit.

  3. Mercury Remediation Technology Development for Lower East Fork Poplar Creek - FY 2016 Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Dickson, Johnbull O. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Smith, John G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Mehlhorn, Tonia L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Peterson, Mark J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Lowe, Kenneth Alan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Watson, David B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Brooks, Scott C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Morris, Jesse G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Mayes, Melanie [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Johs, Alexander [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Mathews, Teresa J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); McManamay, Ryan A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); DeRolph, Christopher R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Poteat, Monica D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Olsen, Todd A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Eller, Virginia A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC); Gonez Rodriguez, Leroy [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC)

    2017-07-01

    Mercury remediation is a high priority for the US Department of Energy (DOE) Oak Ridge Office of Environmental Management (OREM), especially at and near the Y-12 National Security Complex (Y-12) where historical mercury use has resulted in contaminated buildings, soils, and downstream surface waters. To address mercury contamination of East Fork Poplar Creek (EFPC), the DOE has adopted a phased, adaptive management approach to remediation, which includes mercury treatment actions at Y-12 in the short-term and research and technology development (TD) to evaluate longer-term solutions in the downstream environment (US Department of Energy 2014).

  4. Evaluation of Lower East Fork Poplar Creek Mercury Sources - Model Update

    Energy Technology Data Exchange (ETDEWEB)

    Ketelle, Richard [East Tennessee Technology Park (ETTP), Oak Ridge, TN (United States); Brandt, Craig C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peterson, Mark J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevelhimer, Mark S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Watson, David B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brooks, Scott C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mayes, Melanie [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeRolph, Christopher R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dickson, Johnbull O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Olsen, Todd A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    The purpose of this report is to assess new data that has become available and provide an update to the evaluations and modeling presented in the Oak Ridge National Laboratory (ORNL) Technical Manuscript Evaluation of lower East Fork Poplar Creek (LEFPC) Mercury Sources (Watson et al., 2016). Primary sources of field and laboratory data for this update include multiple US Department of Energy (DOE) programs including Environmental Management (EM; e.g., Biological Monitoring and Abatement Program, Mercury Remediation Technology Development [TD], and Applied Field Research Initiative), Office of Science (Mercury Science Focus Areas [SFA] project), and the Y-12 National Security Complex (Y-12) Compliance Department.

  5. Oxbow Conservation Area; Middle Fork John Day River, Annual Report 2001-2002.

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Shaun; Smith, Brent; Cochran, Brian

    2003-04-01

    In early 2001, the Confederated Tribes of Warm Springs, through their John Day Basin Office, concluded the acquisition of the Middle Fork Oxbow Ranch. Under a memorandum of agreement with the Bonneville Power Administration (BPA), the Tribes are required to provided BPA an 'annual written report generally describing the real property interests in the Project, HEP analyses undertaken or in progress, and management activities undertaken or in progress'. This report is to be provided to the BPA by 30 April of each year. This is the first annual report filed for the Oxbow Ranch property.

  6. Note: Wide band amplifier for quartz tuning fork sensors with digitally controlled stray capacitance compensation.

    Science.gov (United States)

    Peng, Ping; Hao, Lifeng; Ding, Ning; Jiao, Weicheng; Wang, Qi; Zhang, Jian; Wang, Rongguo

    2015-11-01

    We presented a preamplifier design for quartz tuning fork (QTF) sensors in which the stray capacitance is digitally compensated. In this design, the manually controlled variable capacitor is replaced by a pair of varicap diodes, whose capacitance could be accurately tuned by a bias voltage. A tuning circuit including a single side low power operational amplifier, a digital-to-analog converter, and a microprocessor is also described, and the tuning process can be conveniently carried out on a personal computer. For the design, the noise level was investigated experimentally.

  7. The effectiveness of front fork systems at damping accelerations during isolated aspects specific to cross-country mountain biking.

    Science.gov (United States)

    Macdermid, Paul W; Miller, Matthew C; Fink, Philip W; Stannard, Stephen R

    2017-11-01

    Cross-country mountain bike suspension reportedly enhances comfort and performance through reduced vibration and impact exposure. This study analysed the effectiveness of three different front fork systems at damping accelerations during the crossing of three isolated obstacles (stairs, drop, and root). One participant completed three trials on six separate occasions in a randomised order using rigid, air-sprung, and carbon leaf-sprung forks. Performance was determined by time to cross obstacles, while triaxial accelerometers quantified impact exposure and damping response. Results identified significant main effect of fork type for performance time (p aspects of cross-country terrain features which may be influenced to a larger extent by rider technique.

  8. Qualitative Assessment: Evaluating the Impacts of Climate Change on Endangered Species Act Recovery Actions for the South Fork Nooksack River, WA

    Science.gov (United States)

    The South Fork Nooksack River (South Fork) is located in northwest Washington State and is home to nine species of Pacific salmon, including Nooksack early Chinook (aka, spring Chinook salmon), an iconic species for the Nooksack Indian Tribe. The quantity of salmon in the South F...

  9. The Model Analysis of a Complex Tuning Fork Probe and Its Application in Bimodal Atomic Force Microscopy

    Directory of Open Access Journals (Sweden)

    Zhichao Wu

    2017-01-01

    Full Text Available A new electromechanical coupling model was built to quantitatively analyze the tuning fork probes, especially the complex ones. A special feature of a novel, soft tuning fork probe, that the second eigenfrequency of the probe was insensitive to the effective force gradient, was found and used in a homemade bimodal atomic force microscopy to measure power dissipation quantitatively. By transforming the mechanical parameters to the electrical parameters, a monotonous and concise method without using phase to calculate the power dissipation was proposed.

  10. Effect of paddock vs. stall housing on 24 hour gastric pH within the proximal and ventral equine stomach.

    Science.gov (United States)

    Husted, L; Sanchez, L C; Olsen, S N; Baptiste, K E; Merritt, A M

    2008-06-01

    Stall housing has been suggested as a risk factor for ulcer development in the equine stomach; however, the exact pathogenesis for this has not been established. To investigate the effect of 3 environmental situations (grass paddock, stall alone or stall with adjacent companion) on pH in the proximal and the ventral stomach. Six horses with permanently implanted gastric cannulae were used in a randomised, cross-over, block design. Each horse rotated through each of three 24 h environmental situations. Horses remained on their normal diet (grass hay ad libitum and grain b.i.d.) throughout the study. Intragastric pH was measured continuously for 72 h just inside the lower oesophageal sphincter (proximal stomach) and via a pH probe in the gastric cannula (ventral stomach). Neither proximal nor ventral 24 h gastric pH changed significantly between the 3 environmental situations. Mean hourly proximal gastric pH decreased significantly in the interval from 01.00-09.00 h compared to the interval from 13.00-20.00 h, regardless of environmental situation. Median hourly proximal pH only differed in the interval from 06.00-07.00 h compared to the interval 14.00-19.00 h. Neither mean nor median hourly ventral gastric pH varied significantly with the time of day. The change in housing status used in the current study did not affect acid exposure within either region of the equine stomach. The pH in the ventral stomach was uniformly stable throughout the study, while the proximal pH demonstrated a 24 h circadian pattern.

  11. The ammonoids from the Three Forks Shale (Late Devonian of Montana

    Directory of Open Access Journals (Sweden)

    D. Korn

    2006-08-01

    Full Text Available The ammonoid fauna from the Late Devonian Three Forks Shale of Montana is revised. Six taxa were recognised, which belong to the genera Tornoceras, Pernoceras, Raymondiceras, Platyclymenia, Pleuroclymenia, and Carinoclymenia. The ammonoid assemblage suggests a stratigraphic position within the middle Famennian, most probably the Platyclymenia annulata Zone. The ammonoids display extreme septal crowding in intermediate as well as adult growth stages, which can be regarded as evidence for instable palaeoecological conditions during lifetime of the animals. Die Ammonoideenfauna aus dem oberdevonischen Three Forks Shale von Montana wird revidiert. Sechs Taxa werden unterschieden; sie gehören zu den Gattungen Tornoceras, Pernoceras, Raymondiceras, Platyclymenia, Pleuroclymenia und Carinoclymenia. Die Ammonoideen-Vergesellschaftung spricht für eine stratigraphische Position im mittleren Famennium, wahrscheinlich in der Platyclymenia annulata Zone. Die Ammonoideen zeigen auffällige Drängung der Septen in intermediären und adulten Wachstumsstadien, die als Hinweis auf instabile Lebensbedingungen für die Tiere gewertet werden kann. doi:10.1002/mmng.200600008

  12. Correlates of mercury in fish from lakes near Clyde Forks, Ontario, Canada

    International Nuclear Information System (INIS)

    Ethier, A.L.M.; Scheuhammer, A.M.; Bond, D.E.

    2008-01-01

    Subsurface soils near Clyde Forks, Ontario, Canada, can have naturally high concentrations of mercury (Hg) from local geological sources. To investigate Hg in local aquatic food webs, Hg was measured in fish dorsal muscle (mainly yellow perch [YP] and pumpkinseed sunfish [PS]) and surface sediments from 10 regional lakes. Water chemistry, along with fork length, weight, and stable isotopes (δ 15 N, δ 13 C, δ 34 S) in fish were also measured. No lake sediments had elevated (>0.3 μg/g dw) Hg, and average Hg concentrations in fish were not sufficiently high ( 13 C), and certain lake variables (e.g., pH for YP). PS with more pelagic feeding habits had higher δ 34 S and Hg than those with more littoral feeding habits. Potential biological linkages between fish Hg and δ 34 S, a parameter that may be related to the lake sulphate-reducing bacteria activity, requires further investigation. - Fish from lakes near a localized geological Hg source do not have elevated Hg concentrations

  13. Chromatin Controls DNA Replication Origin Selection, Lagging-Strand Synthesis, and Replication Fork Rates.

    Science.gov (United States)

    Kurat, Christoph F; Yeeles, Joseph T P; Patel, Harshil; Early, Anne; Diffley, John F X

    2017-01-05

    The integrity of eukaryotic genomes requires rapid and regulated chromatin replication. How this is accomplished is still poorly understood. Using purified yeast replication proteins and fully chromatinized templates, we have reconstituted this process in vitro. We show that chromatin enforces DNA replication origin specificity by preventing non-specific MCM helicase loading. Helicase activation occurs efficiently in the context of chromatin, but subsequent replisome progression requires the histone chaperone FACT (facilitates chromatin transcription). The FACT-associated Nhp6 protein, the nucleosome remodelers INO80 or ISW1A, and the lysine acetyltransferases Gcn5 and Esa1 each contribute separately to maximum DNA synthesis rates. Chromatin promotes the regular priming of lagging-strand DNA synthesis by facilitating DNA polymerase α function at replication forks. Finally, nucleosomes disrupted during replication are efficiently re-assembled into regular arrays on nascent DNA. Our work defines the minimum requirements for chromatin replication in vitro and shows how multiple chromatin factors might modulate replication fork rates in vivo. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  14. The conventional tuning fork as a quantitative tool for vibration threshold.

    Science.gov (United States)

    Alanazy, Mohammed H; Alfurayh, Nuha A; Almweisheer, Shaza N; Aljafen, Bandar N; Muayqil, Taim

    2018-01-01

    This study was undertaken to describe a method for quantifying vibration when using a conventional tuning fork (CTF) in comparison to a Rydel-Seiffer tuning fork (RSTF) and to provide reference values. Vibration thresholds at index finger and big toe were obtained in 281 participants. Spearman's correlations were performed. Age, weight, and height were analyzed for their covariate effects on vibration threshold. Reference values at the fifth percentile were obtained by quantile regression. The correlation coefficients between CTF and RSTF values at finger/toe were 0.59/0.64 (P = 0.001 for both). Among covariates, only age had a significant effect on vibration threshold. Reference values for CTF at finger/toe for the age groups 20-39 and 40-60 years were 7.4/4.9 and 5.8/4.6 s, respectively. Reference values for RSTF at finger/toe for the age groups 20-39 and 40-60 years were 6.9/5.5 and 6.2/4.7, respectively. CTF provides quantitative values that are as good as those provided by RSTF. Age-stratified reference data are provided. Muscle Nerve 57: 49-53, 2018. © 2017 Wiley Periodicals, Inc.

  15. The Oak Ridge Y-12 Plant biological monitoring and abatement program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J.M.; Adams, S.M.; Allison, L.J.; Giddings, J.M.; McCarthy, J.F.; Southworth, G.R.; Smith, J.G.; Stewart, A.J. (Oak Ridge National Lab., TN (USA); Springborn Bionomics, Inc., Wareham, MA (USA); Oak Ridge National Lab., TN (USA))

    1989-10-01

    In May 1985, a National Pollutant Discharge Elimination System permit was issued for the Oak Ridge Y-12 Plant, a nuclear weapons components production facility located in Oak Ridge, Tennessee, and operated by Martin Marietta Energy Systems, Inc., for the US Department of Energy. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Oak Ridge Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek), in particular, the growth and propagation of fish and aquatic life, as designated by the Tennessee Department of Health and Environment. A second purpose for the BMAP is to document the ecological effects resulting from implementation of a water pollution control program that will include construction of nine new wastewater treatment facilities over the next 4 years. Because of the complex nature of the effluent discharged to East Fork Poplar Creek and the temporal and spatial variability in the composition of the effluent (i.e., temporal variability related to various pollution abatement measures that will be implemented over the next several years and spatial variability caused by pollutant inputs downstream of the Oak Ridge Y-12 Plant), a comprehensive, integrated approach to biological monitoring was developed for the BMAP. 39 refs., 5 figs., 8 tabs.

  16. Investigation of shallow groundwater contamination near East Fork Poplar Creek, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Carmichael, J.K.

    1989-01-01

    Alluvial soils of the flood plain of East Fork Poplar Creek in Oak Ridge, Tennessee, are contaminated with mercury and other metals, organic compounds, and radionuclides originating from the Y-12 Plant, a nuclear-processing facility located within the US Department of Energy's Oak Ridge Reservation. Observation wells were installed in the shallow aquifer of the flood plain, and water quality samples were collected to determine if contaminants are present in the shallow groundwater. Groundwater in the shallow aquifer occurs under water-table conditions. Recharge is primarily from precipitation and discharge is to East Fork Poplar Creek. Groundwater levels fluctuate seasonally in response to variations in recharge and evapotranspiration. During extremely dry periods, the water table drops below the base of the shallow aquifer in some flood-plain areas. Contaminants were found in water samples from several of the wells in concentrations which equaled or exceeded drinking-water standards established by the US Environmental Protection Agency are antimony, chromium, lead, mercury, selenium, phenols, and strontium-90. Total and dissolved uranium concentrations exceeded the analytical detection limit in nearly 70% of the wells in the flood plain. The results of water quality determinations demonstrate that elevated concentrations of most trace metals (and possibly organic compounds and radionuclides) were caused by contaminated sediments in the samples. The presence of contaminated sediment in samples is suspected to be the result of borehole contamination during well installation. 21 refs., 20 figs., 6 tabs

  17. Aero-elastic stability of airfoil flow using 2-D CFD

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, J. [Risoe National Lab., Roskilde (Denmark)

    1999-03-01

    A three degrees-of-freedom structural dynamics model has been coupled to a two-dimensional incompressible CFD code. The numerical investigation considers aero-elastic stability for two different airfoils; the NACA0012 and the LM 2 18 % airfoils. Stable and unstable configurations and limit cycle oscillations are predicted in accordance with literature for the first airfoil. An attempt to predict stall induced edge-wise vibrations on a wind turbine airfoil fails using this two-dimensional approach. (au)

  18. The Effects of Gilts Housed Either in Group with the Electronic Sow Feeding System or Conventional Stall.

    Science.gov (United States)

    Jang, J C; Jung, S W; Jin, S S; Ohh, S J; Kim, J E; Kim, Y Y

    2015-10-01

    This experiment was conducted to assess the welfare and productivity of gestating gilts in groups with the electronic sow feeding (ESF) system compared to conventional stalls. A total of 83 gilts (Yorkshire×Landrace) were housed into individual stalls to be artificially inseminated. Gilts confirmed pregnant were introduced to their treatment, conventional stalls (ST) or groups with the ESF system. All gilts were taken to the farrowing crates one week prior to their expected farrowing date. In the gestation period, there were no significant differences between gilts allocated to ST and ESF on growth performance. However, backfat thickness gain (p = 0.08) and body condition score (BCS) at 110 days of gestation (p = 0.10) tended to be higher in ESF gilts than ST. Likewise, gilts housed in group showed significantly higher estimated body muscle contents at 110 days of gestation (p = 0.02) and body muscle change during gestation (p = 0.01). There was a trend for a shorter parturition time in ESF gilts (p = 0.07). In the lactation period, group housed gilts showed a tendency to increased BCS changes (p = 0.06). Reproductive performance did not differ with the exception of piglet mortality (ST = 0.2 no. of piglets vs ESF = 0.4 no. of piglets; p = 0.01). In blood profiles, ST gilts showed a higher cortisol level at 110 days of gestation (p = 0.01). Weaning to estrus interval was shorter in gilts housed in ESF than ST (p = 0.01). In locomotory behaviors, ESF gilts recorded a tendency to elevate locomotion score at 36, 70, and 110 days of gestation (p = 0.07, p = 0.06, and p = 0.06, respectively). Similarly, ESF gilts showed significantly higher incidence of scratches at 36, 70, and 110 days of gestation (p = 0.01). Moreover, farrowing rates were higher in stall treatment (97.6%) compare to group housing treatment (95.2%). In conclusion, while group housed gilts with ESF system positively affected welfare status in combination with less physiologically stressful

  19. Water Quality and Biological Characteristics of the Middle Fork of the Saline River, Arkansas, 2003-06

    Science.gov (United States)

    Galloway, Joel M.; Petersen, James C.; Shelby, Erica L.; Wise, Jim A.

    2008-01-01

    The Middle Fork of the Saline River has many qualities that have been recognized by State and Federal agencies. The Middle Fork provides habitat for several rare aquatic species and is part of a larger stream system (the Upper Saline River) that is known for relatively high levels of species richness and relatively high numbers of species of concern. Water-quality samples were collected and streamflow was measured by the U.S. Geological Survey at three sites in the Middle Fork Basin between October 2003 and October 2006. The Arkansas Department of Environmental Quality collected discrete synoptic water-quality samples from eight sites between January 2004 and October 2006. The Arkansas Department of Environmental Quality also sampled fish (September-October 2003) and benthic macroinvertebrate communities (September 2003-December 2005) at five sites. Streamflow varied annually among the three streamflow sites from October 2003 to October 2006. The mean annual streamflow for Brushy Creek near Jessieville (MFS06) was 0.72 cubic meters per second for water years 2004-2006. The Middle Fork below Jessieville (MFS05) had a mean annual streamflow of 1.11 cubic meters per second for water years 2004-2006. The Middle Fork near Owensville (MFS02), the most downstream site, had a mean annual streamflow of 3.01 cubic meters per second. The greatest streamflows at the three sites generally occurred in the winter and spring and the least in the summer. Nutrient dynamics in the Middle Fork are controlled by activities in the basin and processes that occur in the stream. Point sources and nonpoint sources of nutrients occur in the Middle Fork Basin that could affect the water-quality. Nitrogen and phosphorus concentrations generally were greatest in Mill Creek (MFS04E) and in the Middle Fork immediately downstream from the confluence with Mill Creek (MFS04) with decreasing concentrations at sites farther downstream in Middle Fork. The site in Mill Creek is located downstream from a

  20. Hydrologic modeling of flood conveyance and impacts of historic overbank sedimentation on West Fork Black's Fork, Uinta Mountains, northeastern Utah, USA

    Science.gov (United States)

    Carson, Eric C.

    2006-05-01

    This study assesses historic overbank alluvial sedimentation along a low-gradient reach of West Fork Black's Fork in the northern Uinta Mountains, Utah. In this previously glaciated setting, an alluvial floodplain that is approximately 400 m wide by 1500 m long has been modified by the combined effects of valley morphometry and the recent history of clear-cut logging during the late 19th and early 20th Centuries. To quantify the effects on sedimentation and flow conveyance, three natural streambank exposures were sampled and analyzed for nuclear bomb fallout 137Cs. The distribution of 137Cs within the three profiles suggests that a remnant outwash terrace exerts a first-order control over the deposition of overbank alluvium. Upstream from a constriction in the floodplain caused by the terrace remnant, as much as 40 cm of overbank alluvium has been deposited since the beginning of clear-cut logging. Immediately downstream of that constriction, no evidence exists for any overbank sedimentation during that same period. Vibracore samples and Oakfield soil probe sampling throughout the study reach quantified the geographic extent and thicknesses of the historic alluvial package. Flood conveyance through the study area was modeled using the U.S. Army Corps of Engineers HEC-RAS modeling program. Model simulations were run for modern conditions (using surveyed topography) and for prehistoric conditions (using the modern topography less the historic alluvial package determined by 137Cs analyses). Model results indicate that the floodplain constriction caused a significant impediment to flood conveyance at even modest discharges during prehistoric conditions. This promoted ponding of floodwaters upstream of the constriction and deposition of alluvium. This has increased bank heights upstream of the constriction, to the point that under modern conditions 1- to 5-year recurrence interval floods are largely confined within the channel. These results confirm the validity of this

  1. Cable Stability

    CERN Document Server

    Bottura, L

    2014-01-01

    Superconductor stability is at the core of the design of any successful cable and magnet application. This chapter reviews the initial understanding of the stability mechanism, and reviews matters of importance for stability such as the nature and magnitude of the perturbation spectrum and the cooling mechanisms. Various stability strategies are studied, providing criteria that depend on the desired design and operating conditions.

  2. The effect of real-time vibrotactile feedback delivered through an augmented fork on eating rate, satiation, and food intake

    NARCIS (Netherlands)

    Roel C. J. Hermans; Sander Hermsen; Eric Robinson; Suzanne Higgs; Jeana H. Frost; Monica Mars

    2017-01-01

    Eating rate is a basic determinant of appetite regulation, as people who eat more slowly feel sated earlier and eat less. Without assistance, eating rate is difficult to modify due to its automatic nature. In the current study, participants used an augmented fork that aimed to decelerate their rate

  3. Mapping Prehistoric, Historic, and Channel Sediment Distribution, South Fork Noyo River: A Tool For Understanding Sources, Storage, and Transport

    Science.gov (United States)

    Rich D. Koehler; Keith I. Kelson; Graham Matthews; K.H. Kang; Andrew D. Barron

    2007-01-01

    The South Fork Noyo River (SFNR) watershed in coastal northern California contains large volumes of historic sediment that were delivered to channels in response to past logging operations. This sediment presently is stored beneath historic terraces and in present-day channels. We conducted geomorphic mapping on the SFNR valley floor to assess the volume and location...

  4. Spatio-temporal patterns of the decline of fresh water mussels in the Little South Fork Cumberland River,USA

    Science.gov (United States)

    Melvin L. Warren; Wendell R. Haag

    2005-01-01

    The Little South Fork Cumberland River, Kentucky and Tennessee, USA, was a globally important conservation refugium for freshwater mussels (Mollusca:Unionidae) because it supported an intact example (26 species) of the unique Cumberland River mussel fauna including imperiled species. We used previous surveys and our 1997–1998 survey to reconstruct the historical fauna...

  5. The Escherichia coli Tus-Ter replication fork barrier causes site-specific DNA replication perturbation in yeast

    DEFF Research Database (Denmark)

    Larsen, Nicolai B; Sass, Ehud; Suski, Catherine

    2014-01-01

    Replication fork (RF) pausing occurs at both 'programmed' sites and non-physiological barriers (for example, DNA adducts). Programmed RF pausing is required for site-specific DNA replication termination in Escherichia coli, and this process requires the binding of the polar terminator protein, Tu...

  6. Fork2Farmer: Enabling Success of Small Farms through Partnerships with Well-Known Chefs and the Tourism Sector

    Science.gov (United States)

    Morais, Duarte; Jakes, Susan; Bowen, Becky; Lelekacs, Joanna Massey

    2017-01-01

    A team of economic development, local foods, and tourism specialists from North Carolina Cooperative Extension is pursuing an initiative titled Fork2Farmer. The goal is to increase visits to local farms and diversify farm income by leveraging the high visibility of well-known farm-to-table chefs who support local small farms. To do this, those…

  7. Demonstration of Advanced Geophysics and Classification Methods on Munitions Response Sites - East Fork Valley Range Complex, Former Camp Hale

    Science.gov (United States)

    2016-04-01

    Technical Report Demonstration of Advanced Geophysics and Classification Methods on Munitions Response Sites - East Fork Valley...AECOM Distribution Statement A FINAL REPORT Demonstration of Advanced Geophysics and Classification Methods on Munitions Response Sites East...NUMBER (Include area code) 12-06-2013 Final Report May - November 2014 Demonstration of Advanced Geophysics and Classification Methods on Munitions

  8. 75 FR 41237 - Public Land Order No. 7746; Withdrawal of Public Lands, South Fork of the American River; California

    Science.gov (United States)

    2010-07-15

    ... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLCAC08000-L1430000-ET0000; CACA 41334] Public Land Order No. 7746; Withdrawal of Public Lands, South Fork of the American River; California AGENCY: Bureau of Land Management, Interior. ACTION: Public Land Order. SUMMARY: This order withdraws 2...

  9. Theory of single-molecule controlled rotation experiments, predictions, tests, and comparison with stalling experiments in F1-ATPase.

    Science.gov (United States)

    Volkán-Kacsó, Sándor; Marcus, Rudolph A

    2016-10-25

    A recently proposed chemomechanical group transfer theory of rotary biomolecular motors is applied to treat single-molecule controlled rotation experiments. In these experiments, single-molecule fluorescence is used to measure the binding and release rate constants of nucleotides by monitoring the occupancy of binding sites. It is shown how missed events of nucleotide binding and release in these experiments can be corrected using theory, with F 1 -ATP synthase as an example. The missed events are significant when the reverse rate is very fast. Using the theory the actual rate constants in the controlled rotation experiments and the corrections are predicted from independent data, including other single-molecule rotation and ensemble biochemical experiments. The effective torsional elastic constant is found to depend on the binding/releasing nucleotide, and it is smaller for ADP than for ATP. There is a good agreement, with no adjustable parameters, between the theoretical and experimental results of controlled rotation experiments and stalling experiments, for the range of angles where the data overlap. This agreement is perhaps all the more surprising because it occurs even though the binding and release of fluorescent nucleotides is monitored at single-site occupancy concentrations, whereas the stalling and free rotation experiments have multiple-site occupancy.

  10. Flood-inundation maps for North Fork Salt Creek at Nashville, Indiana

    Science.gov (United States)

    Martin, Zachary W.

    2017-11-13

    Digital flood-inundation maps for a 3.2-mile reach of North Fork Salt Creek at Nashville, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science website at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding that correspond to selected water levels (stages) at the North Fork Salt Creek at Nashville, Ind., streamgage (USGS station number 03371650). Real-time stages at this streamgage may be obtained from the USGS National Water Information System at http://waterdata.usgs.gov/nwis or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also shows observed USGS stages at the same site as the USGS streamgage (NWS site NFSI3).Flood profiles were computed for the stream reach by means of a one-dimensional, step-backwater hydraulic modeling software developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated using the current (2015) stage-discharge rating at the USGS streamgage 03371650, North Fork Salt Creek at Nashville, Ind. The hydraulic model was then used to compute 12 water-surface profiles for flood stages at 1-foot (ft) intervals, except for the highest profile of 22.9 ft, referenced to the streamgage datum ranging from 12.0 ft (the NWS “action stage”) to 22.9 ft, which is the highest stage of the current (2015) USGS stage-discharge rating curve and 1.9 ft higher than the NWS “major flood stage.” The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging data having a 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) to delineate the area flooded at each stage.The availability of these maps, along with information regarding current stage from the USGS

  11. Current mercury distribution and bioavailability in floodplain soils of Lower East Fork Poplar Creek, Oak Ridge, Tennessee, USA

    International Nuclear Information System (INIS)

    Han, Fengxiang X.; Su, Yi; Monts, David L.

    2011-01-01

    The objectives of this study were to investigate the current status of mercury distribution, speciation and bioavailability in the floodplain soils of Lower East Fork Poplar Creek (LEFPC) after decades of US Department of Energy's remediation. Historically as part of its national security mission, the U.S. Department of Energy's Y-12 National Security Facility in Oak Ridge, TN, USA acquired a significant fraction of the world's supply of elemental mercury. During the 1950s and 1960s, a large amount of elemental mercury escaped confinement and is still present in the watershed surrounding the Y-12 facility. A series of remediation efforts have been deployed in the watersheds around the Oak Ridge site during the following years. The sampling fields were located in a floodplain of LEFPC of Oak Ridge, TN, USA. A series of surface soils (10-20 cm) were sampled from both wooded areas and wetland/grass land. Two 8x8 m fields were selected in the woodland. Five profiles each consisting of three layers were randomly taken from each field. The three layers were the surface layer at 0-10cm, subsurface layer at 50-60 cm, and bottom layer at 100-110 cm. Soil in both wood and wetland areas was well developed with a clear B horizon. The present study clearly shows that the total mercury in floodplain soils of LEFPC significantly decreased after the series of remediation. This study confirmed the long-term effectiveness of these remediation actions, especially after excavation of highly contaminated floodplain soils. However, the average total mercury level of all soil samples collected are in the range of 50-80 mg/kg, still significantly above toxic level (> 5mg/kg). Furthermore, contrary to conventional believing, the major mercury form in current soils of this particular area of floodplain of LEFPC is mainly in non-cinnabar mercury bound in clay minerals (after decades of remediation). The floodplains can act both as a medium-term sink and as long-term sources. Native North

  12. Water-quality, bed-sediment, and biological data (October 2012 through September 2013) and statistical summaries of data for streams in the Clark Fork Basin, Montana

    Science.gov (United States)

    Dodge, Kent A.; Hornberger, Michelle I.; Dyke, Jessica

    2014-01-01

    Water, bed sediment, and biota were sampled in streams from Butte to near Missoula, Montana, as part of a monitoring program in the upper Clark Fork Basin of western Montana. The sampling program was led by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency to characterize aquatic resources in the Clark Fork Basin, with emphasis on trace elements associated with historic mining and smelting activities. Sampling sites were located on the Clark Fork and selected tributaries. Water samples were collected periodically at 20 sites from October 2012 through September 2013. Bed-sediment and biota samples were collected once at 13 sites during August 2013.

  13. Water-quality, bed-sediment, and biological data (October 2013 through September 2014) and statistical summaries of data for streams in the Clark Fork Basin, Montana

    Science.gov (United States)

    Dodge, Kent A.; Hornberger, Michelle I.

    2015-12-24

    Water, bed sediment, and biota were sampled in streams from Butte to near Missoula, Montana, as part of a monitoring program in the upper Clark Fork Basin of western Montana. The sampling program was led by the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, to characterize aquatic resources in the Clark Fork Basin, with emphasis on trace elements associated with historic mining and smelting activities. Sampling sites were located on the Clark Fork and selected tributaries. Water samples were collected periodically at 20 sites from October 2013 through September 2014. Bed-sediment and biota samples were collected once at 14 sites during August 2014.

  14. A time-gated fluorescence detector using a tuning fork chopper.

    Science.gov (United States)

    Li, Qingyang; Dasgupta, Purnendu K; Temkin, Henryk

    2008-05-26

    We describe an affordable gated fluorescence detection system to measure fluorescent compounds with long-lifetimes that uses a tuning fork chopper to block the intense excitation pulse from a flash lamp or short-lived fluorescence. A conventional non-gated inexpensive photosensor module is used to collect the luminescence signal. Using the long-lived luminescence from the terbium(III)-dipicolinic acid (DPA) chelate, we demonstrate a limit of detection (LOD) of 120pM for DPA. This system is not only an order of magnitude less expensive than an electronically gateable phototomultiplier tube (GPMT), it exhibits no evidence of gradual loss of sensitivity, due likely to photocathode fatigue and deterioration, observed with a GPMT.

  15. The phase interrogation method for optical fiber sensor by analyzing the fork interference pattern

    Science.gov (United States)

    Lv, Riqing; Qiu, Liqiang; Hu, Haifeng; Meng, Lu; Zhang, Yong

    2018-02-01

    The phase interrogation method for optical fiber sensor is proposed based on the fork interference pattern between the orbital angular momentum beam and plane wave. The variation of interference pattern with phase difference between the two light beams is investigated to realize the phase interrogation. By employing principal component analysis method, the features of the interference pattern can be extracted. Moreover, the experimental system is designed to verify the theoretical analysis, as well as feasibility of phase interrogation. In this work, the Mach-Zehnder interferometer was employed to convert the strain applied on sensing fiber to the phase difference between the reference and measuring paths. This interrogation method is also applicable for the measurements of other physical parameters, which can produce the phase delay in optical fiber. The performance of the system can be further improved by employing highlysensitive materials and fiber structures.

  16. Chronology of Deformation Near the Iditarod-Nixon Fork Fault, West-Central Alaska

    Science.gov (United States)

    Perttu, B. K.; Wallace, W. K.; Newberry, R. J.; Layer, P. W.

    2010-12-01

    The Nixon Fork Mine is a Cu-Au deposit located 7 km south of the Iditarod-Nixon Fork (I-NF) fault. This fault strikes at ~060°, and can be traced for ~400 km, with a minimum dextral displacement of ~90 km. Proximity to the I-NF fault suggests it would be a dominant influence on deformation of the deposit, but the extent and timing of disruption are unknown. In order to reconstruct strain history and eventually understand structural evolution, we analyzed the orientations of geologic structures and dated representative K-bearing minerals and rocks. Felsic dikes, with 40Ar/39Ar ages of 69.6 ± 0.5 Ma and arc-type signatures, are cut by faults apparently related to the I-NF fault, but do not obviously cut such faults. Since no dikes are seen to cut faults, we know of no local fault motion prior to their intrusion. The northeast strike of the felsic dikes (n = 102; mean = 034° ± 10° ) requires σ3 oriented ~124°, at odds with the ~0° orientation inferred from the strike of the I-NF fault (~60°). The Nixon Fork pluton has approximately the same age and an overall elongation compatible with the felsic dikes. Mafic dikes, with 40Ar/39Ar ages of 62.8 ± 0.6 Ma, have within-plate signatures (average TiO2 = 2.48 wt%, Zr = 172 ppm, Nb = 58 ppm, Y = 25 ppm) and require a change in overall tectonic regime. Additionally, their north strike (n = 44; mean = 013° ± 10°) requires σ3 oriented ~103°, which is not compatible with σ3 (~0°) inferred from the right-lateral I-NF fault, and requires a different extension direction from the felsic dikes. We observed mafic dikes cut by faults with orientations compatible with right-lateral motion on the I-NF fault, and we propose that right-lateral motion on the I-NF fault began after mafic dike emplacement. Outcrop-scale fold axes trend north (n = 136; mean = 355° ± 10°). They are preferentially aligned perpendicular to the σ1 inferred for right-lateral motion on the I-NF fault and so are plausibly related to the I-NF fault

  17. Modulation of mutagenesis in eukaryotes by DNA replication fork dynamics and quality of nucleotide pools

    Science.gov (United States)

    Waisertreiger, Irina S.-R.; Liston, Victoria G.; Menezes, Miriam R.; Kim, Hyun-Min; Lobachev, Kirill S.; Stepchenkova, Elena I.; Tahirov, Tahir H.; Rogozin, Igor B.; Pavlov, Youri. I.

    2014-01-01

    The rate of mutations in eukaryotes depends on a plethora of factors and is not immediately derived from the fidelity of DNA polymerases (Pols). Replication of chromosomes containing the anti-parallel strands of duplex DNA occurs through the copying of leading and lagging strand templates by a trio of Pols α, δ and ε, with the assistance of Pol ζ and Y-family Pols at difficult DNA template structures or sites of DNA damage. The parameters of the synthesis at a given location are dictated by the quality and quantity of nucleotides in the pools, replication fork architecture, transcription status, regulation of Pol switches, and structure of chromatin. The result of these transactions is a subject of survey and editing by DNA repair. PMID:23055184

  18. Mercury Remediation Technology Development for Lower East Fork Poplar Creek - FY 2015 Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Mark J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Brooks, Scott C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Mathews, Teresa J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Mayes, Melanie [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Johs, Alexander [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Watson, David B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Poteat, Monica D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Smith, John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Mehlhorn, Tonia [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Lester, Brian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Morris, Jesse [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Lowe, Kenneth [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division; Dickson, Johnbull O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Eller, Virginia [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeRolph, Christopher R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division

    2016-04-01

    Mercury remediation is a high priority for the US Department of Energy (DOE) Oak Ridge Office of Environmental Management (OREM) because of large historical losses of mercury within buildings and to soils and surface waters at the Y-12 National Security Complex (Y-12). Because of the extent of mercury losses and the complexities of mercury transport and fate in the downstream environment, the success of conventional options for mercury remediation in lower East Fork Poplar Creek (EFPC) is uncertain. A phased, adaptive management approach to remediation of surface water includes mercury treatment actions at Y-12 in the short-term and research and technology development (TD) to evaluate longer-term solutions in the downstream environment (US Department of Energy 2014b).

  19. Mercury Remediation Technology Development for Lower East Fork Poplar Creek - FY 2015 Progress Report

    International Nuclear Information System (INIS)

    Peterson, Mark J.; Smith, John; Eller, Virginia; DeRolph, Christopher R.

    2016-01-01

    Mercury remediation is a high priority for the US Department of Energy (DOE) Oak Ridge Office of Environmental Management (OREM) because of large historical losses of mercury within buildings and to soils and surface waters at the Y-12 National Security Complex (Y-12). Because of the extent of mercury losses and the complexities of mercury transport and fate in the downstream environment, the success of conventional options for mercury remediation in lower East Fork Poplar Creek (EFPC) is uncertain. A phased, adaptive management approach to remediation of surface water includes mercury treatment actions at Y-12 in the short-term and research and technology development (TD) to evaluate longer-term solutions in the downstream environment (US Department of Energy 2014b).

  20. South Fork Salmon River Watershed Restoration, 2008-2009 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Reaney, Mark D. [Nez Perce Tribe Department of Fisheries Resource Management

    2009-04-15

    The watershed restoration work elements within the project area, the South Fork Salmon River Watershed, follow the watershed restoration approach adopted by the Nez Perce Tribe Department of Fisheries Resource Management (DFRM) - Watershed Division. The vision of the Nez Perce Tribe DFRM-Watershed Division focuses on protecting, restoring, and enhancing watersheds and treaty resources within the ceded territory of the Nez Perce Tribe under the Treaty of 1855 with the United States Federal Government. The program uses a holistic approach, which encompasses entire watersheds, ridge top to ridge top, emphasizing all cultural aspects and strategies that rely on natural fish production and healthy river ecosystems. The Nez Perce Tribe DFRM-Watershed Division strives towards maximizing historic ecosystem productivity and health for the restoration of anadromous and resident fish populations and the habitat on which all depend on for future generations Originally, this project was funded to create a step/pool stream channel that was appropriate to restore fish passage where the 'Glory Hole Cascade' is currently located at the Stibnite Mine. Due to unforeseen circumstances at the time, the project is unable to move forward as planned and a request for a change in scope of the project and an expansion of the geographic area in which to complete project work was submitted. No additional funds were being requested. The ultimate goal of this project is to work with the holistic, ridge top to ridge top approach to protect and restore the ecological and biological functions of the South Fork Salmon River Watershed to assist in the recovery of threatened and endangered anadromous and resident fish species. FY 2008 Work Elements included two aquatic organism passage (AOP) projects to restore habitat connectivity to two fish-bearing tributaries to the East Fork South Fork Salmon River, Salt and Profile Creeks. The Work Elements also included road survey and assessment

  1. Waste management plan for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    The Lower East Fork Poplar Creek (LEFPC) Remedial Action project will remove mercury-contaminated soils from the floodplain of LEFPC, dispose of these soils at the Y-12 Plant Landfill V, and restore the affected floodplain. The waste management plan addresses management and disposition of all wastes generated during the LEFPC remedial action. Most of the solid wastes will be sanitary or construction/demolition wastes and will be disposed of at existing Y- 12 facilities. Some small amounts of hazardous waste are anticipated, along with possible low-level or mixed wastes (> 35 pCi/g). Liquid wastes will be generated which will be sanitary and capable of being disposed of at the Oak Ridge Sewage Treatment Plant, except sanitary sewage.

  2. Waste management plan for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-04-01

    The Lower East Fork Poplar Creek (LEFPC) Remedial Action project will remove mercury-contaminated soils from the floodplain of LEFPC, dispose of these soils at the Y-12 Plant Landfill V, and restore the affected floodplain. The waste management plan addresses management and disposition of all wastes generated during the LEFPC remedial action. Most of the solid wastes will be sanitary or construction/demolition wastes and will be disposed of at existing Y- 12 facilities. Some small amounts of hazardous waste are anticipated, along with possible low-level or mixed wastes (> 35 pCi/g). Liquid wastes will be generated which will be sanitary and capable of being disposed of at the Oak Ridge Sewage Treatment Plant, except sanitary sewage

  3. Quartz enhanced photoacoustic spectroscopy based trace gas sensors using different quartz tuning forks.

    Science.gov (United States)

    Ma, Yufei; Yu, Guang; Zhang, Jingbo; Yu, Xin; Sun, Rui; Tittel, Frank K

    2015-03-27

    A sensitive trace gas sensor platform based on quartz-enhanced photoacoustic spectroscopy (QEPAS) is reported. A 1.395 μm continuous wave (CW), distributed feedback pigtailed diode laser was used as the excitation source and H2O was selected as the target analyte. Two kinds of quartz tuning forks (QTFs) with a resonant frequency (f0) of 30.72 kHz and 38 kHz were employed for the first time as an acoustic wave transducer, respectively for QEPAS instead of a standard QTF with a f0 of 32.768 kHz. The QEPAS sensor performance using the three different QTFs was experimentally investigated and theoretically analyzed. A minimum detection limit of 5.9 ppmv and 4.3 ppmv was achieved for f0 of 32.768 kHz and 30.72 kHz, respectively.

  4. Tennessee's East Fork Poplar Creek: A biological monitoring and abatement program

    International Nuclear Information System (INIS)

    Halbrook, R.S.; Loar, J.M.; Adams, S.M.; Black, M.C.; Boston, H.L.; Greeley, M.S. Jr.; Hill, W.R.; Hinzman, R.L.; McCarthy, J.F.; Peterson, M.J.; Ryon, M.G.; Schilling, E.M.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.; Gatz, A.J.

    1991-01-01

    On May 1985, a Biological Monitoring Program was developed for East Fork Poplar Creek (EFPC) in eastern Tennessee, United States. This stream originates within the Oak Ridge Y-12 Plant that produces nuclear weapons components for the Department of Energy. Water and sediment in the stream contain metals, organic chemicals, and radionuclides from releases that have occurred over the past 45 years. The creek also receives urban and some agricultural runoff and effluent from the City of Oak Ridge's Wastewater Treatment Facility (WTF). The biological monitoring program includes four major tasks: (1) ambient toxicity testing: (2) bioaccumulation studies; (3) biological indicator studies; and (4) ecological monitoring of stream communities, including periphyton, benthic macroinvertebrates, and fish. Biological conditions are monitored at six sites on EFPC ranging from kilometer 24.4 near the headwaters to kilometer 6.3 near the month. A site on Brushy Fork, A stream just north of Oak Ridge, is used as reference. Ambient (instream) toxicity was monitored through the use of 7-day static-renewal tests that measured the survival and growth of fathead minnow (Pimephales promelas) larvae and the survival and reproduction of a microstrustacean (Ceriodaphnia dubia). Full-strength water from EFPC within the Y-12 Plant boundary was frequently toxic to Ceriodaphnia, but less frequently toxic to the minnow larvae. Chlorine has been identified as an important toxicant in upper EFPC. Water samples from six sites in EFPC downstream from the Y-12 Plant boundary were tested eight times with both species during a 2-year period (October, 1986 through October, 1988). These sites were ranked by the number of times they were ''best'' or ''worst'' for each species. Water samples collected for use in the ambient toxicity tests were routinely analyzed for conductivity, pH, alkalinity, hardness, total residual and free chlorine, and temperature

  5. Following an imaginary Campylobacter population from farm to fork and beyond: a bacterial perspective.

    Science.gov (United States)

    Wassenaar, T M

    2011-09-01

    It has been known for decades that poultry meat is the most common single source for campylobacteriosis, yet the problem has not been solved. This review identifies some of the reasons why our attempts to reduce the incidence of this pathogen have largely failed. Based on the literature, the events a virtual population of Campylobacter may encounter, from growing in the gut of a broiler to eventually infecting humans and causing disease, are reviewed. Most steps in the farm-to-fork process are well studied, though there are gaps in our knowledge about survival and spread of Campylobacter populations before they enter the farm. Key events in the farm-to-fork chain that are suitable targets for prevention and control, to reduce food-borne campylobacteriosis, are indicated. Novel insights into the pathogenic mechanism responsible for disease in humans are summarized, which hypothesize that an overactive immune response is the reason for the typical inflammatory diarrhoea. A role of genetic microheterogeneity within a clonal population in this chain of events is being proposed here. The human host is not necessary for the survival of the bacterial species, nor have these bacteria specifically evolved to cause disease in that host. More likely, the species evolved for a commensal life in birds, and human disease can be considered as collateral damage owing to an unfortunate host-microbe interaction. The indirect environmental burden that results from poultry production should not be ignored as it may pose a diffuse, but possibly significant risk factor for disease. © 2011 The Author. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

  6. Water-quality trends for selected sampling sites in the upper Clark Fork Basin, Montana, water years 1996-2010

    Science.gov (United States)

    Sando, Steven K.; Vecchia, Aldo V.; Lorenz, David L.; Barnhart, Elliott P.

    2014-01-01

    A large-scale trend analysis was done on specific conductance, selected trace elements (arsenic, cadmium, copper, iron, lead, manganese, and zinc), and suspended-sediment data for 22 sites in the upper Clark Fork Basin for water years 1996–2010. Trend analysis was conducted by using two parametric methods: a time-series model (TSM) and multiple linear regression on time, streamflow, and season (MLR). Trend results for 1996–2010 indicate moderate to large decreases in flow-adjusted concentrations (FACs) and loads of copper (and other metallic elements) and suspended sediment in Silver Bow Creek upstream from Warm Springs. Deposition of metallic elements and suspended sediment within Warm Springs Ponds substantially reduces the downstream transport of those constituents. However, mobilization of copper and suspended sediment from floodplain tailings and stream banks in the Clark Fork reach from Galen to Deer Lodge is a large source of metallic elements and suspended sediment, which also affects downstream transport of those constituents. Copper and suspended-sediment loads mobilized from within this reach accounted for about 40 and 20 percent, respectively, of the loads for Clark Fork at Turah Bridge (site 20); whereas, streamflow contributed from within this reach only accounted for about 8 percent of the streamflow at Turah Bridge. Minor changes in FACs and loads of copper and suspended sediment are indicated for this reach during 1996–2010. Clark Fork reaches downstream from Deer Lodge are relatively smaller sources of metallic elements than the reach from Galen to Deer Lodge. In general, small decreases in loads and FACs of copper and suspended sediment are indicated for Clark Fork sites downstream from Deer Lodge during 1996–2010. Thus, although large decreases in FACs and loads of copper and suspended sediment are indicated for Silver Bow Creek upstream from Warm Springs, those large decreases are not translated to the more downstream reaches largely

  7. Mass loading of selected major and trace elements in Lake Fork Creek near Leadville, Colorado, September-October 2001

    Science.gov (United States)

    Walton-Day, Katherine; Flynn, Jennifer L.; Kimball, Briant A.; Runkel, Robert L.

    2005-01-01

    A mass-loading study of Lake Fork Creek of the Arkansas River between Sugarloaf Dam and the mouth was completed in September-October 2001 to help ascertain the following: (1) variation of pH and aqueous constituent concentrations (calcium, sulfate, alkalinity, aluminum, cadmium, copper, iron, manganese, lead, and zinc) and their relation to toxicity standards along the study reach; (2) location and magnitude of sources of metal loading to Lake Fork Creek; (3) amount and locations of metal attenuation; (4) the effect of streamside wetlands on metal transport from contributing mine tunnels; and (5) the effect of organic-rich inflow from the Leadville National Fish Hatchery on water quality in Lake Fork Creek. The study was done in cooperation with the Bureau of Land Management, U.S. Department of Agriculture Forest Service, and U.S. Fish and Wildlife Service. Constituent concentrations and pH showed variable patterns over the study reach. Hardness-based acute and chronic toxicity standards were exceeded for some inflows and some constituents. However, stream concentrations did not exceed standards except for zinc starting in the upper parts of the study reach and extending to just downstream from the inflow from the Leadville National Fish Hatchery. Dilution from that inflow lowered stream zinc concentrations to less than acute and chronic toxicity standards. The uppermost 800 meters of the study reach that contained inflow from the Bartlett, Dinero, and Nelson mine tunnels and the Dinero wetland was the greatest source of loading for manganese and zinc. A middle section of the study reach that extended approximately 2 kilometers upstream from the National Fish Hatchery inflow to just downstream from that inflow was the largest source of aluminum, copper, iron, and lead loading. The loading was partially from the National Fish Hatchery inflow but also from unknown sources upstream from that inflow, possibly ground water. The largest sources for calcium and sulfate

  8. Grid connection of active stall wind farms using a VSC based DC transmission system

    DEFF Research Database (Denmark)

    Iov, F.; Sørensen, Poul Ejnar; Hansen, A.D.

    2005-01-01

    Currently, there is an increasing trend to connect large MW wind farms to the transmission system. Requirements that focus on the influence of the farms on the grid stability and power quality, and on the control capabilities of wind farms have already been established. The main trends of modern...... wind turbines/farms are clearly the variable speed operation and a grid connection through a power electronic interface, especially using doubly fed induction generators. Using power electronics the control capabilities of these wind turbines/farms are extended and thus the grid requirements...... are fulfilled. However, the traditional squirrel-cage generators based wind turbines/wind farms directly connected to the grid have less control capabilities. These wind turbines/farms cannot regulate their production and contribute to power system stability. A DC transmission system for connection...

  9. Variable frequency operation of active stall wind farms using a dc connection to grid

    DEFF Research Database (Denmark)

    Iov, Florin; Blaabjerg, Frede; Sorensen, Poul

    2005-01-01

    Currently, there is an increasing trend to connect large MW wind farms to the transmISSIon system. Requirements that focus on the influence of the farms on the grid stability and power quality, and on the control capabilities of wind farms have already been established. The main trends of modern...... wind turbines/farms are clearly the variable speed operation and a grid connection through a power electronic interface, especially using doubly-fed induction generators. Using power electronics the control capabilities of these wind turbines/farms are extended and thus the grid requirements...... are fulfilled. However, the traditional squirrel-cage generators based wind turbines/wind farms directly connected to the grid have less control capabilities. These wind turbines/farms cannot regulate their production and contribute to power system stability. A DC transmission system for connection...

  10. Effects of the inlet boundary layer thickness on the flow in an axial compressor (I) : hub corner stall and tip leakage flow

    International Nuclear Information System (INIS)

    Choi, Min Suk; Baek, Je Hyun; Park, Jun Young

    2005-01-01

    A three-dimensional computation was conducted to understand effects of the inlet boundary layer thickness on the internal flow in a low-speed axial compressor operating at the design condition(φ=85%) and near stall condition(φ=65%). At the design condition, the flows in the axial compressor show, independent of the inlet boundary layer thickness, similar characteristics such as the pressure distribution, size of the hub corner-stall, tip leakage flow trajectory, limiting streamlines on the blade suction surface, etc. However, as the load is increased, the hub corner-stall grows to make a large separation region at the junction of the hub and suction surface for the inlet condition with thick boundary layers at the hub and casing. Moreover, the tip leakage flow is more vortical than that observed in case of the thin inlet boundary layer and has the critical point where the trajectory of the tip leakage flow is abruptly turned into the downstream. For the inlet condition with thin boundary layers, the hub corner-stall is diminished so it is indistinguishable from the wake. The tip leakage flow leans to the leading edge more than at the design condition but has no critical point. In addition to these, the severe reverse flow, induced by both boundary layer on the blade surface and the tip leakage flow, can be found to act as the blockage of flows near the casing, resulting in heavy loss

  11. Stall/surge dynamics of a multi-stage air compressor in response to a load transient of a hybrid solid oxide fuel cell-gas turbine system

    Science.gov (United States)

    Azizi, Mohammad Ali; Brouwer, Jacob

    2017-10-01

    A better understanding of turbulent unsteady flows in gas turbine systems is necessary to design and control compressors for hybrid fuel cell-gas turbine systems. Compressor stall/surge analysis for a 4 MW hybrid solid oxide fuel cell-gas turbine system for locomotive applications is performed based upon a 1.7 MW multi-stage air compressor. Control strategies are applied to prevent operation of the hybrid SOFC-GT beyond the stall/surge lines of the compressor. Computational fluid dynamics tools are used to simulate the flow distribution and instabilities near the stall/surge line. The results show that a 1.7 MW system compressor like that of a Kawasaki gas turbine is an appropriate choice among the industrial compressors to be used in a 4 MW locomotive SOFC-GT with topping cycle design. The multi-stage radial design of the compressor enhances the ability of the compressor to maintain air flow rate during transient step-load changes. These transient step-load changes are exhibited in many potential applications for SOFC/GT systems. The compressor provides sustained air flow rate during the mild stall/surge event that occurs due to the transient step-load change that is applied, indicating that this type of compressor is well-suited for this hybrid application.

  12. Analysis of the Unsteady Flow Field in a Centrifugal Compressor from Peak Efficiency to Near Stall with Full-Annulus Simulations

    Directory of Open Access Journals (Sweden)

    Yannick Bousquet

    2014-01-01

    Full Text Available This study concerns a 2.5 pressure ratio centrifugal compressor stage consisting of a splittered unshrouded impeller and a vaned diffuser. The aim of this paper is to investigate the modifications of the flow structure when the operating point moves from peak efficiency to near stall. The investigations are based on the results of unsteady three-dimensional simulations, in a calculation domain comprising all the blade. A detailed analysis is given in the impeller inducer and in the vaned diffuser entry region through time-averaged and unsteady flow field. In the impeller inducer, this study demonstrates that the mass flow reduction from peak efficiency to near stall leads to intensification of the secondary flow effects. The low momentum fluid accumulated near the shroud interacts with the main flow through a shear layer zone. At near stall condition, the interface between the two flow structures becomes unstable leading to vortices development. In the diffuser entry region, by reducing the mass flow, the high incidence angle from the impeller exit induces a separation on the diffuser vane suction side. At near stall operating point, vorticity from the separation is shed into vortex cores which are periodically formed and convected downstream along the suction side.

  13. Final report from VFL technologies for the pilot-scale thermal treatment of Lower East Fork Poplar Creek floodplain soils: LEFPC appendices, volume 1, appendix I-IV

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-09-01

    This document contains Appendix I-IV for the pilot-scale thermal treatment of lower East Fork Poplar Creek floodplain soils. Included are calibration records; quality assurance; soils characterization; pilot scale trial runs.

  14. Final report from VFL technologies for the pilot-scale thermal treatment of Lower East Fork Poplar Creek floodplain soils: LEFPC appendices, volume 1, appendix I-IV

    International Nuclear Information System (INIS)

    1994-09-01

    This document contains Appendix I-IV for the pilot-scale thermal treatment of lower East Fork Poplar Creek floodplain soils. Included are calibration records; quality assurance; soils characterization; pilot scale trial runs

  15. Vacuum properties of high quality value tuning fork in high magnetic field up to 8 Tesla and at mK temperatures

    Science.gov (United States)

    Človečko, M.; Kupka, M.; Skyba, P.; Vavrek, F.

    2014-12-01

    Tuning forks are very popular experimental tools widely applied in low and ultra low temperature physics as mechanical resonators and cantilevers in the study of quantum liquids, STM and AFM techniques, etc. As an added benefit, these forks being cooled, have very high Q-value, typically 106 and their properties seems to be magnetic field independent. We present preliminary vacuum measurements of a commercial tuning fork oscillating at frequency 32 kHz conducted in magnetic fields up to 8 T and at temperature ~ 10 mK. We found an additional weak damping of the tuning fork motion depending on magnetic field magnitude and we discuss physical nature of the observed phenomena.

  16. Global increase in replication fork speed during a p57KIP2-regulated erythroid cell fate switch.

    Science.gov (United States)

    Hwang, Yung; Futran, Melinda; Hidalgo, Daniel; Pop, Ramona; Iyer, Divya Ramalingam; Scully, Ralph; Rhind, Nicholas; Socolovsky, Merav

    2017-05-01

    Cell cycle regulators are increasingly implicated in cell fate decisions, such as the acquisition or loss of pluripotency and self-renewal potential. The cell cycle mechanisms that regulate these cell fate decisions are largely unknown. We studied an S phase-dependent cell fate switch, in which murine early erythroid progenitors transition in vivo from a self-renewal state into a phase of active erythroid gene transcription and concurrent maturational cell divisions. We found that progenitors are dependent on p57 KIP2 -mediated slowing of replication forks for self-renewal, a novel function for cyclin-dependent kinase inhibitors. The switch to differentiation entails rapid down-regulation of p57 KIP2 with a consequent global increase in replication fork speed and an abruptly shorter S phase. Our work suggests that cell cycles with specialized global DNA replication dynamics are integral to the maintenance of specific cell states and to cell fate decisions.

  17. Hydrogeology and simulated groundwater flow and availability in the North Fork Red River aquifer, southwest Oklahoma, 1980–2013

    Science.gov (United States)

    Smith, S. Jerrod; Ellis, John H.; Wagner, Derrick L.; Peterson, Steven M.

    2017-09-28

    On September 8, 1981, the Oklahoma Water Resources Board established regulatory limits on the maximum annual yield of groundwater (343,042 acre-feet per year) and equal-proportionate-share (EPS) pumping rate (1.0 acre-foot per acre per year) for the North Fork Red River aquifer. The maximum annual yield and EPS were based on a hydrologic investigation that used a numerical groundwater-flow model to evaluate the effects of potential groundwater withdrawals on groundwater availability in the North Fork Red River aquifer. The Oklahoma Water Resources Board is statutorily required (every 20 years) to update the hydrologic investigation on which the maximum annual yield and EPS were based. Because 20 years have elapsed since the final order was issued, the U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board, conducted an updated hydrologic investigation and evaluated the effects of potential groundwater withdrawals on groundwater flow and availability in the North Fork Red River aquifer in Oklahoma. This report describes a hydrologic investigation of the North Fork Red River aquifer that includes an updated summary of the aquifer hydrogeology. As part of this investigation, groundwater flow and availability were simulated by using a numerical groundwater-flow model.The North Fork Red River aquifer in Beckham, Greer, Jackson, Kiowa, and Roger Mills Counties in Oklahoma is composed of about 777 square miles (497,582 acres) of alluvium and terrace deposits along the North Fork Red River and tributaries, including Sweetwater Creek, Elk Creek, Otter Creek, and Elm Fork Red River. The North Fork Red River is the primary source of surface-water inflow to Lake Altus, which overlies the North Fork Red River aquifer. Lake Altus is a U.S. Bureau of Reclamation reservoir with the primary purpose of supplying irrigation water to the Lugert-Altus Irrigation District.A hydrogeologic framework was developed for the North Fork Red River aquifer and included a

  18. Controlling the quality factor of a tuning-fork resonance between 9 and 300 K for scanning-probe microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ctistis, G; Frater, E H; Huisman, S R; Korterik, J P; Herek, J L; Vos, W L; Pinkse, P W H, E-mail: g.ctistis@utwente.nl, E-mail: P.W.H.Pinkse@utwente.nl [MESA Institute for Nanotechnology, University of Twente, 7500 AE Enschede (Netherlands)

    2011-09-21

    We study the dynamic response of a mechanical quartz tuning fork in the temperature range from 9 to 300 K. Since the quality factor Q of the resonance strongly depends on temperature, we implement a procedure to control the quality factor of the resonance. We show that we are able to dynamically change the quality factor and keep it constant over the whole temperature range. This procedure is suitable for applications in scanning-probe microscopy.

  19. Assessing the potential for rainbow trout reproduction in tributaries of the Mountain Fork River below Broken Bow Dam, southeastern Oklahoma

    Science.gov (United States)

    Long, James M.; Starks, Trevor A.; Farling, Tyler; Bastarache, Robert

    2016-01-01

    Stocked trout (Salmonidae) in reservoir tailwater systems in the Southern United States have been shown to use tributary streams for spawning and rearing. The lower Mountain Fork of the Little River below Broken Bow Dam is one of two year-round tailwater trout fisheries in Oklahoma, and the only one with evidence of reproduction by stocked rainbow trout (Oncorhynchus mykiss). Whether stocked trout use tributaries in this system for spawning is unknown. Furthermore, an

  20. Spatially detailed quantification of metal loading for decision making: Metal mass loading to American fork and Mary Ellen Gulch, Utah

    Science.gov (United States)

    Kimball, B.A.; Runkel, R.L.

    2009-01-01

    Effective remediation requires an understanding of the relative contributions of metals from all sources in a catchment, and that understanding must be based on a spatially detailed quantification of metal loading. A traditional approach to quantifying metal loading has been to measure discharge and chemistry at a catchment outlet. This approach can quantify annual loading and the temporal changes in load, but does not provide the needed spatial detail to evaluate specific sources, which is needed to support remediation decisions. A catchment or massloading approach provides spatial detail by combining tracer-injection and synoptic-sampling methods to quantify loading. Examples of studies in American Fork, Utah, and its tributary Mary Ellen Gulch illustrate this different approach. The mass-loading study in American Fork treated Mary Ellen Gulch as a single inflow. From that point of view, Mary Ellen Gulch was one of the greatest sources of Fe, Mn, Zn, and colloidal Pb loads to American Fork. But when Mary Ellen Gulch was evaluated in a separate catchment study, the detailed locations of metal loading were identified, and the extent of metal attenuation upstream from the mouth of Mary Ellen Gulch was quantified. The net, instantaneous load measured at the mouth of Mary Ellen Gulch for remediation planning would greatly underestimate the contributions of principal sources within the catchment. Extending the detailed sampling downstream from Mary Ellen Gulch indicated the possibility of diffuse groundwater inflow from Mary Ellen Gulch to American Fork. Comparing loads for Mary Ellen Gulch in the two studies indicates that metal loads could be substantially underestimated for planning purposes without the detailed catchment approach for the low-flow conditions in these studies. A mass-loading approach provides both the needed quantification of metal loading and the spatial detail to guide remediation decisions that would be the most effective in the catchments

  1. Confirmatory Sampling and Analysis Plan for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-12-01

    This document describes the organization, strategy, and procedures to be used to confirm that mercury concentrations in soils in the remediated areas are statistically less than, or equal to, the cleanup standard of 400 ppm. It focuses on confirming the cleanup of the stretch of the Lower East Fork Popular Creed flowing from Lake Reality at the Y-12 Plant, through the City of Oak Ridge, to Poplar Creek on the Oak Ridge Reservation and its associated flood plain

  2. Aerial gamma ray and magnetic survey: Minnesota Project, Grand Forks quadrangle of Minnesota/North Dakota. Final report

    International Nuclear Information System (INIS)

    1979-12-01

    The Grand Forks 1:250,000 scale quadrangle of Minnesota and North Dakota is almost everywhere covered with Wisconsin age glacial deposits (drift, lake sediments, etc.) of variable thickness. Where exposed, bedrock is Late Cretaceous age marine deposits. There are no uranium deposits (or occurrences) known within the quadrangle. Seventy-eight (78) groups of uranium samples were defined as anomalies and are discussed briefly in this report. None of them are considered significant

  3. Confirmatory Sampling and Analysis Plan for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    This document describes the organization, strategy, and procedures to be used to confirm that mercury concentrations in soils in the remediated areas are statistically less than, or equal to, the cleanup standard of 400 ppm. It focuses on confirming the cleanup of the stretch of the Lower East Fork Popular Creed flowing from Lake Reality at the Y-12 Plant, through the City of Oak Ridge, to Poplar Creek on the Oak Ridge Reservation and its associated flood plain.

  4. Suppression of inducer stall based on inlet recirculation in a centrifugal impeller. 1st Report. Improvement in stall limit by ring groove arrangement; Enshin haneguruma iriguchi junkanryu ni yoru inducer shissoku no yokusei. 1. kanjoko ni yoru shissoku genkai no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Ueki, H.; Ishida, M.; Sakaguchi, D.; Sun, Z. [Nagasaki University, Nagasaki (Japan). Faculty of Engineering

    2000-07-25

    A ring groove arrangement is proposed to suppress unstable flow or surge in a centrifugal blower. The ring groove arrangement connects the upstream position of impeller inlet and the inducer throat tip through a bypass. The recirculation flow 'vas formed by the pressure difference between the two positions, and the recirculation flow rate was changed by increasing the ring groove widths. The inlet recirculation results in a decrease in the flow rate of unstable flow inception, and an up to 800 improvement in stall limit was obtained by the ring groove arrangement at a small expense of the delivery pressure drop. The improvement of stall limit in the present experiment seems to be mainly due to decrease in flow incidence based on the inlet recirculation flow. Tre flow incidence decreases more as the recirculation flow rate increases, thus resulting in a larger improvement in stall limit. (author)

  5. Hypermutagenesis in mutA cells is mediated by mistranslational corruption of polymerase, and is accompanied by replication fork collapse.

    Science.gov (United States)

    Al Mamun, Abu Amar M; Gautam, Satyendra; Humayun, M Zafri

    2006-12-01

    Elevated mistranslation induces a mutator response termed translational stress-induced mutagenesis (TSM) that is mediated by an unidentified modification of DNA polymerase III. Here we address two questions: (i) does TSM result from direct polymerase corruption, or from an indirect pathway triggered by increased protein turnover? (ii) Why are homologous recombination functions required for the expression of TSM under certain conditions, but not others? We show that replication of bacteriophage T4 in cells expressing the mutA allele of the glyVtRNA gene (Asp-Gly mistranslation), leads to both increased mutagenesis, and to an altered mutational specificity, results that strongly support mistranslational corruption of DNA polymerase. We also show that expression of mutA, which confers a recA-dependent mutator phenotype, leads to increased lambdoid prophage induction (selectable in vivo expression technology assay), suggesting that replication fork collapse occurs more frequently in mutA cells relative to control cells. No such increase in prophage induction is seen in cells expressing alaVGlu tRNA (Glu-->Ala mistranslation), in which the mutator phenotype is recA-independent. We propose that replication fork collapse accompanies episodic hypermutagenic replication cycles in mutA cells, requiring homologous recombination functions for fork recovery, and therefore, for mutation recovery. These findings highlight hitherto under-appreciated links among translation, replication and recombination, and suggest that translational fidelity, which is affected by genetic and environmental signals, is a key modulator of replication fidelity.

  6. Fork-join and data-driven execution models on multi-core architectures: Case study of the FMM

    KAUST Repository

    Amer, Abdelhalim

    2013-01-01

    Extracting maximum performance of multi-core architectures is a difficult task primarily due to bandwidth limitations of the memory subsystem and its complex hierarchy. In this work, we study the implications of fork-join and data-driven execution models on this type of architecture at the level of task parallelism. For this purpose, we use a highly optimized fork-join based implementation of the FMM and extend it to a data-driven implementation using a distributed task scheduling approach. This study exposes some limitations of the conventional fork-join implementation in terms of synchronization overheads. We find that these are not negligible and their elimination by the data-driven method, with a careful data locality strategy, was beneficial. Experimental evaluation of both methods on state-of-the-art multi-socket multi-core architectures showed up to 22% speed-ups of the data-driven approach compared to the original method. We demonstrate that a data-driven execution of FMM not only improves performance by avoiding global synchronization overheads but also reduces the memory-bandwidth pressure caused by memory-intensive computations. © 2013 Springer-Verlag.

  7. South Fork Flathead Watershed Westslope Cutthroat Trout Conservation Program, Annual Report 2002.

    Energy Technology Data Exchange (ETDEWEB)

    Grisak, Grant; Marotz, Brian

    2003-06-01

    In 1999, Montana Fish, Wildlife & Parks (MFWP) began a program aimed at conserving the genetically pure populations of westslope cutthroat trout in the South Fork Flathead River drainage. The objective of this program is to eliminate all of the exotic and hybrid trout that threaten the genetically pure westslope cutthroat populations in the South Fork Flathead. The exotic and hybrid trout populations occur in several headwater lakes and their outflow streams. In 2001 MFWP released a draft environmental assessment, pursuant to the Montana Environmental Policy Act (MEPA), that addressed the use of motorized equipment to deliver personnel and materials to some of these lakes in the Bob Marshall and Great Bear Wildernesses (Grisak 2001). After a 30-day public comment period, MFWP determined that the complexity of issues was too great and warranted a more detailed analysis. These issues included transportation options for personnel, equipment and materials, the use of motorized equipment in wilderness, fish removal methods, fish stocking, and the status and distribution of amphibian populations in the project area. Because the program also involves the U.S. Forest Service (USFS) and Bonneville Power Administration (BPA), the environmental analysis needs to comply with the National Environmental Policy Act (NEPA). In October 2001, pursuant to NEPA, MFWP, along with the USFS and BPA initiated an environmental assessment to address these issues. In June 2002, the three agencies determined that the scope of these issues warranted an Environmental Impact Statement. This specialist report describes the logistical, technical and biological issues associated with this project and provides an analysis of options for fish removal, transportation and fish stocking. It further analyzes issues and concerns associated with amphibian populations and creating new domesticated stocks of westslope cutthroat trout. Finally, this document provides a description of each lake, the best

  8. Quarterly Progress Report - Biological Monitoring Program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Adams, S.M.; Christensen, S.W.; Greeley, M.S. jr; Hill, W.R.; McCarthy, J.F.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.

    2000-07-18

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Loar et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities. Monitoring is currently being conducted at five primary EFPC sites, although sites may be excluded or added depending upon the specific objectives of the various tasks. Criteria used in selecting the sites include: (1) location of sampling sites used in other studies, (2) known or suspected sources of downstream impacts, (3) proximity to U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR) boundaries, (4) concentration of mercury in the adjacent floodplain, (5) appropriate habitat distribution, and

  9. Quarterly Progress Report - Biological Monitoring Program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Adams, S.M.; Christensen, S.W.; Greeley, M.S.jr; Hill, W.R.; McCarthy, J.F.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.

    2000-04-18

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Loar et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities. Monitoring is currently being conducted at five primary EFPC sites, although sites may be excluded or added depending upon the specific objectives of the various tasks. Criteria used in selecting the sites include: (1) location of sampling sites used in other studies, (2) known or suspected sources of downstream impacts, (3) proximity to U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR) boundaries, (4) concentration of mercury in the adjacent floodplain, (5) appropriate habitat distribution, and

  10. Quarterly Progress Report - Biological Monitoring Program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Adams, S.M.; Christensen, S.W.; Greeley, M.S.jr; Hill, W.R.; McCarthy, J.F.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.

    2000-10-18

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Loar et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities. Monitoring is currently being conducted at five primary EFPC sites, although sites may be excluded or added depending upon the specific objectives of the various tasks. Criteria used in selecting the sites include: (1) location of sampling sites used in other studies, (2) known or suspected sources of downstream impacts, (3) proximity to U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR) boundaries, (4) concentration of mercury in the adjacent floodplain, (5) appropriate habitat distribution, and

  11. Modelling and Control of VSC based DC Connection for Active Stall Wind Farms to Grid

    DEFF Research Database (Denmark)

    Iov, Florin; Sørensen, Poul; Hansen, Anca Daniela

    2006-01-01

    Currently, there is an increasing trend to connect large MW wind farms to the transmission system. Therefore the power system becomes more vulnerable and dependent on the wind energy production. At the same time requirements that focus on the influence of the farms on the grid stability and power...... quality, and on the control capabilities of wind farms have already been established. The main trends of modern wind turbines/farms are clearly the variable speed operation and a grid connection through a power electronic interface, especially using doubly-fed induction generators. Using power electronics...... the control capabilities of these wind turbines/farms are extended and thus the grid requirements are fulfilled.  However, the traditional squirrel-cage generators based wind turbines/wind farms directly connected to the grid does not have such control capabilities. They produce maximum possible power...

  12. Modeling and Control of VSC based DC Connection for Active Stall Wind Farms to Grid

    DEFF Research Database (Denmark)

    Iov, Florin; Sorensen, Poul; Hansen, Anca-Daniela

    2005-01-01

    Currently, there is an increasing trend to connect large MW wind farms to the transmission system. Therefore the power system becomes more vulnerable and dependent on the wind energy production. At the same time requirements that focus on the influence of the farms on the grid stability and power...... quality, and on the control capabilities of wind farms have already been established. The main trends of modem wind turbines/farms are clearly the variable speed operation and a grid connection through a power electronic interface, especially using doubly-fed induction generators. Using power electronics...... the control capabilities of these wind turbines/farms are extended and thus the grid requirements are fulfilled. However, the traditional squirrel-cage generators based wind turbines/wind farms directly connected to the grid does not have such control capabilities. They produce maximum possible power...

  13. Understanding DNA Repair in Hyperthermophilic Archaea: Persistent Gaps and Other Reasons to Focus on the Fork

    Directory of Open Access Journals (Sweden)

    Dennis W. Grogan

    2015-01-01

    Full Text Available Although hyperthermophilic archaea arguably have a great need for efficient DNA repair, they lack members of several DNA repair protein families broadly conserved among bacteria and eukaryotes. Conversely, the putative DNA repair genes that do occur in these archaea often do not generate the expected phenotype when deleted. The prospect that hyperthermophilic archaea have some unique strategies for coping with DNA damage and replication errors has intellectual and technological appeal, but resolving this question will require alternative coping mechanisms to be proposed and tested experimentally. This review evaluates a combination of four enigmatic properties that distinguishes the hyperthermophilic archaea from all other organisms: DNA polymerase stalling at dU, apparent lack of conventional NER, lack of MutSL homologs, and apparent essentiality of homologous recombination proteins. Hypothetical damage-coping strategies that could explain this set of properties may provide new starting points for efforts to define how archaea differ from conventional models of DNA repair and replication fidelity.

  14. Remedial design work plan for Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1995-10-01

    The Remedial Design Work Plan (RDWP) for Lower East Fork Poplar Creek (EFPC) Operable Unit (OU) in Oak Ridge, Tennessee. This remedial action fits into the overall Oak Ridge Reservation (ORR) cleanup strategy by addressing contaminated floodplain soil. The objective of this remedial action is to minimize the risk to human health and the environment from contaminated soil in the Lower EFPC floodplain pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Federal Facility Agreement (FFA) (1992). In accordance with the FFA, a remedial investigation (RI) (DOE 1994a) and a feasibility study (DOE 1994b) were conducted to assess contamination of the Lower EFPC and propose remediation alternatives. The remedial investigation determined that the principal contaminant is mercury, which originated from releases during Y-12 Plant operations, primarily between 1953 and 1963. The recommended alternative by the feasibility study was to excavate and dispose of floodplain soils contaminated with mercury above the remedial goal option. Following the remedial investigation/feasibility study, and also in accordance with the FFA, a proposed plan was prepared to more fully describe the proposed remedy.

  15. Lessons learned at Lower East Fork Poplar Creek, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Burch, K.L.; Page, D.G.

    1996-01-01

    The US Department of Energy (DOE) used several innovative strategies and technologies in conducting the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) activities for the Lower East Fork Poplar Creek (EFPC) Operable Unit (OU) in Oak Ridge, Tennessee. These innovations helped to cost-effectively characterize the 270-ha (670-acre), 23.3-km (14.5-mile) floodplain and to obtain a 400-parts per million (ppm) cleanup level for mercury in soil. Lessons learned during the project involve management, investigation, and risk assessment strategies and techniques. Management lessons learned include (a) how to handle the large OU, (b) how to effectively involve the community in decisions, and (c) how to select a remedy that incorporates the needs of many involved agencies. Investigation lessons learned include (a) how to design an effective sampling strategy for the site, (b) how to cost-effectively analyze a large number of samples, and (c) which of several treatment technologies is best-suited to the site. Risk assessment lessons learned include (a) how to determine an appropriate cleanup level for human health and the environment, (b) how to quantify uncertainty in the human health risk assessment, (c) how to reconcile different solubilities of different mercury species, and (d) how to best conduct the ecological risk assessment. Other CERCLA sites can benefit from lessons learned during this project whether still in the investigative stage or further along in the process. Applying these lessons can substantially reduce costs and make more efficient use of Superfund resources

  16. CRITICAL CONTROL POINT IDENTIFICATION THROUGH TROPHOLOGICAL MEAT PRODUCTION CHAINFROM FIELD TO FORK

    Directory of Open Access Journals (Sweden)

    A. V. Borodin

    2017-01-01

    Full Text Available  Competitive production management is impossible without comprehensive hazard monitoring and critical parameters control at every stage of food production from raw material and auxiliary materials delivery to ready product realization, which is difficult without modern IT-support. The HACCP (Hazard Analysis and Critical Control Points approach to product safety differs from ready product testing for compliance with NaTD requirements (Normative and Technical Documentation and emphasizes the importance of the process approach to monitoring at every stage of food production. Critical control points (CCP identification is a stage, where the presence of a risk of manufacturing products that are unsafe for human health is recognized and it is possible to take action to its elimination, prevention or reduction to an acceptable level. The use of soſtware package significantly increases the enterprise HACCP system efficiency. The article describes methodological bases for IT-approach to the CCP identification in the trophological meat production chain from field to fork. The algorithmic support and soſtware for the «Decision tree», which allows detecting existing hazards, identifying risks, determining CCPs and describing them, has been developed.

  17. Design of a compact tuning fork-shaped notched ultrawideband antenna for wireless communication application.

    Science.gov (United States)

    Shakib, M N; Moghavvemi, M; Mahadi, W N L

    2014-01-01

    A new compact planar notched ultrawideband (UWB) antenna is designed for wireless communication application. The proposed antenna has a compact size of 0.182λ × 0.228λ × 0.018λ where λ is the wavelength of the lowest operating frequency. The antenna is comprised of rectangular radiating patch, ground plane, and an arc-shaped strip in between radiating patch and feed line. By introducing a new Tuning Fork-shaped notch in the radiating plane, a stopband is obtained. The antenna is tested and measured. The measured result indicated that fabricated antenna has achieved a wide bandwidth of 4.33-13.8 GHz (at -10 dB return loss) with a rejection frequency band of 5.28-6.97 GHz (WiMAX, WLAN, and C-band). The effects of the parameters of the antenna are discussed. The experiment results demonstrate that the proposed antenna can well meet the requirement for the UWB communication in spite of its compactness and small size.

  18. Design of a Compact Tuning Fork-Shaped Notched Ultrawideband Antenna for Wireless Communication Application

    Directory of Open Access Journals (Sweden)

    M. N. Shakib

    2014-01-01

    Full Text Available A new compact planar notched ultrawideband (UWB antenna is designed for wireless communication application. The proposed antenna has a compact size of 0.182λ × 0.228λ × 0.018λ where λ is the wavelength of the lowest operating frequency. The antenna is comprised of rectangular radiating patch, ground plane, and an arc-shaped strip in between radiating patch and feed line. By introducing a new Tuning Fork-shaped notch in the radiating plane, a stopband is obtained. The antenna is tested and measured. The measured result indicated that fabricated antenna has achieved a wide bandwidth of 4.33–13.8 GHz (at −10 dB return loss with a rejection frequency band of 5.28–6.97 GHz (WiMAX, WLAN, and C-band. The effects of the parameters of the antenna are discussed. The experiment results demonstrate that the proposed antenna can well meet the requirement for the UWB communication in spite of its compactness and small size.

  19. An inventory of wetlands in the East Fork Poplar Creek floodplain, Anderson and Roane Counties, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-12-01

    An inventory of wetlands within the floodplain of East Fork Poplar Creek (EFPC) in Anderson and Roane Counties, Tennessee was conducted during October, 1991 through May, 1992 for the US Department of Energy (DOE) by the US Army Corps of Engineers, Nashville District. About 15 miles of EFPC channel and 500 acres of its floodplain are contaminated with mercury and other contaminants released from the Y-12 Plant on the DOE Oak Ridge Reservation. The wetland inventory will serve as baseline information for DOE`s remedial action planning and National Environmental Policy Act compliance efforts related to the contamination. In order to provide broad wetland determinations beyond which future wetland definitions are unlikely to expand, the 1989 Federal Manual for Identifying And Delineating Jurisdictional Wetlands was utilized. Using the manual`s methodology in a contaminated system under the approved health and safety plan presented some unique problems, resulting in intrusive sampling for field indicators of hydric soils being accomplished separately from observation of other criteria. Beginning with wetland areas identified on National Wetland Inventory Maps, the entire floodplain was examined for presence of wetland criteria, and 17 wetlands were identified ranging from 0.01 to 2.81 acres in size. The majority of wetlands identified were sized under 1 acre. Some of the wetlands identified were not delineated on the National Wetland Inventory Maps, and much of the wetland area delineated on the maps did not meet the criteria under the 1989 manual.

  20. Waste Management Plan for the Lower East Fork Poplar Creek Remedial Action Project Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-08-01

    The Lower East Fork Poplar Creek (LEFPC) Remedial Action project will remove mercury-contaminated soils from the floodplain of LEFPC, dispose of these soils at the Y-12 Landfill V, and restore the affected floodplain upon completion of remediation activities. This effort will be conducted in accordance with the Record of Decision (ROD) for LEFPC as a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) action. The Waste Management Plan addresses management and disposition of all wastes generated during the remedial action for the LEFPC Project Most of the solid wastes will be considered to be sanitary or construction/demolition wastes and will be disposed of at existing Y-12 facilities for those types of waste. Some small amounts of hazardous waste are anticipated, and the possibility of low- level or mixed waste exists (greater than 35 pCi/g), although these are not expected. Liquid wastes will be generated which will be sanitary in nature and which will be capable of being disposed 0214 of at the Oak Ridge Sewage Treatment Plant

  1. Waste Management Plan for the Lower East Fork Poplar Creek Remedial Action Project Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The Lower East Fork Poplar Creek (LEFPC) Remedial Action project will remove mercury-contaminated soils from the floodplain of LEFPC, dispose of these soils at the Y-12 Landfill V, and restore the affected floodplain upon completion of remediation activities. This effort will be conducted in accordance with the Record of Decision (ROD) for LEFPC as a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) action. The Waste Management Plan addresses management and disposition of all wastes generated during the remedial action for the LEFPC Project Most of the solid wastes will be considered to be sanitary or construction/demolition wastes and will be disposed of at existing Y-12 facilities for those types of waste. Some small amounts of hazardous waste are anticipated, and the possibility of low- level or mixed waste exists (greater than 35 pCi/g), although these are not expected. Liquid wastes will be generated which will be sanitary in nature and which will be capable of being disposed 0214 of at the Oak Ridge Sewage Treatment Plant.

  2. Salmonella and Campylobacter biofilm formation: a comparative assessment from farm to fork.

    Science.gov (United States)

    Lamas, Alexandre; Regal, Patricia; Vázquez, Beatriz; Miranda, José M; Cepeda, Alberto; Franco, Carlos M

    2018-02-09

    It takes several steps to bring food from the farm to the fork (dining table), and contamination with food-borne pathogens can occur at any point in the process. Campylobacter spp. and Salmonella spp. are the main microorganisms responsible for foodborne disease in the EU. These two pathogens are able to persist throughout the food supply chain thanks to their ability to form biofilms. Owing to the high prevalence of Salmonella and especially of Campylobacter in the food supply chain and the huge efforts of food authorities to reduce these levels, it is of great importance to fully understand their mechanisms of persistence. Diverse studies have evaluated the biofilm-forming capacity of foodborne pathogens isolated at different steps of food production. Nonetheless, the principal obstacle of these studies is to reproduce the real conditions that microorganisms encounter in the food supply chain. While there are a wide number of Salmonella biofilm studies, information on Campylobacter biofilms is still limited. A comparison between the two microorganisms could help to develop new research in the field of Campylobacter biofilms. Therefore, this review evaluates relevant work in the field of Salmonella and Campylobacter biofilms and the applicability of the data obtained from these studies to real working conditions. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  3. Post construction report for Lower East Fork Poplar Creek Project, Phase 1, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-11-01

    This Phase 1 Remedial Action (RA) effort was conducted in accordance with the Record of Decision (ROD) for Lower East Fork Poplar Creek (LEFPC) as a Comprehensive Environmental Response, Compensation, and Liability Act action. The LEFPC, Phase 1 RA removed approximately 5,560 yd 3 of mercury-contaminated soils, ≥ 400 ppm, from selected portions of the National Oceanographic and Atmospheric Administration (NOAA) site LEFPC floodplain from July 8, 1996--September 14, 1996. During excavation activities, pockets of elevated radiologically contaminated soils (greater than 35 pCi/g) were located by the continuous monitoring of the excavation areas and contaminated soils with radiological monitoring instruments. Through characterization sampling it has been determined that ∼ 90 yd 3 are less than 35 pCi/g uranium contaminated and will be transported to the Y-12 Landfill V for disposal and the remaining ∼40 yd 3 do not meet the WAC for radiological constituents included in the Special Waste Permit for Landfill V. The radiologically contaminated soil will be placed in 21st Century containers for storage at the K-25 site

  4. Post construction report for Lower East Fork Poplar Creek Project, Phase 1, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    This Phase 1 Remedial Action (RA) effort was conducted in accordance with the Record of Decision (ROD) for Lower East Fork Poplar Creek (LEFPC) as a Comprehensive Environmental Response, Compensation, and Liability Act action. The LEFPC, Phase 1 RA removed approximately 5,560 yd{sup 3} of mercury-contaminated soils, {ge} 400 ppm, from selected portions of the National Oceanographic and Atmospheric Administration (NOAA) site LEFPC floodplain from July 8, 1996--September 14, 1996. During excavation activities, pockets of elevated radiologically contaminated soils (greater than 35 pCi/g) were located by the continuous monitoring of the excavation areas and contaminated soils with radiological monitoring instruments. Through characterization sampling it has been determined that {approximately} 90 yd{sup 3} are less than 35 pCi/g uranium contaminated and will be transported to the Y-12 Landfill V for disposal and the remaining {approximately}40 yd{sup 3} do not meet the WAC for radiological constituents included in the Special Waste Permit for Landfill V. The radiologically contaminated soil will be placed in 21st Century containers for storage at the K-25 site.

  5. A Z-Axis Quartz Cross-Fork Micromachined Gyroscope Based on Shear Stress Detection

    Science.gov (United States)

    Xie, Liqiang; Wu, Xuezhong; Li, Shengyi; Wang, Haoxu; Su, Jianbin; Dong, Peitao

    2010-01-01

    Here we propose a novel quartz micromachined gyroscope. The sensor has a simple cross-fork structure in the x-y plane of quartz crystal. Shear stress rather than normal stress is utilized to sense Coriolis’ force generated by the input angular rate signal. Compared to traditional quartz gyroscopes, which have two separate sense electrodes on each sidewall, there is only one electrode on each sidewall of the sense beam. As a result, the fabrication of the electrodes is simplified and the structure can be easily miniaturized. In order to increase sensitivity, a pair of proof masses is attached to the ends of the drive beam, and the sense beam has a tapered design. The structure is etched from a z-cut quartz wafer and the electrodes are realized by direct evaporation using the aperture mask method. The drive mode frequency of the prototype is 13.38 kHz, and the quality factor is approximately 1,000 in air. Therefore, the gyroscope can work properly without a vacuum package. The measurement ability of the shear stress detection design scheme is validated by the Coriolis’ force test. The performance of the sensor is characterized on a precision rate table using a specially designed readout circuit. The experimentally obtained scale factor is 1.45 mV/°/s and the nonlinearity is 3.6% in range of ±200 °/s. PMID:22294887

  6. Kinetic energy dissipation of a tuning fork immersed in superfluid helium at different frequencies of oscillations

    International Nuclear Information System (INIS)

    Gritsenko, I.A.; Klokol, K.A.; Sokolov, S.S.; Sheshin, G.A.

    2016-01-01

    An experimental study is made of the drag coefficient, which is the characteristics of energy dissipation during oscillations of the tuning forks, immersed in liquid helium. The experiments were performed in the temperature range from 0.1 to 3.5 K covering both the range of a hydrodynamic flow, and the ballistic regime of transfer of thermal excitations of superfluid helium below 0.6 K. It is found that there is the frequency dependence of the drag coefficient in the hydrodynamic limit, when the main dissipation mechanism is the viscous friction of the fluid against the walls of the oscillating body at temperatures above 0.7 K. In this case, the drag coefficient is proportional to the square root of the frequency of oscillation, and its temperature dependence in He II is determined by the respective dependence of the normal component density of the normal component and the viscosity of the fluid. At lower temperatures, the dependence of drag coefficient on the frequency is not available, and the magnitude of the dissipative losses is determined only by the temperature dependence of the density of the normal component. At the same time in the entire range of temperatures value of dissipative losses depends on the geometry of the oscillating body.

  7. Aeroelastic research programme EFP-2001[YAW;STALL]; Forskning i aeroelasticitet EFP-2001

    Energy Technology Data Exchange (ETDEWEB)

    Aagaard Madsen, H. (ed.)

    2002-12-01

    The project covers the one year period from mid 2001 to mid 2002 and is the last part of a 5 years research programme on aeroelasticity. The overall objectives of the project are to improve the load and design basis for wind turbines and to ensure in collaboration with industry a continu-ously running process on development of new designs and solution of actual problems. Specifi-cally the main objectives for the present period are the following: a) development of a design tool for analysis of dynamic stability b) investigations of blade tip aerodynamics and blade tip design on basis of 3D CFD computa-tions c) publication of an airfoil catalogue d) load reduction using new control strategies e) aeroacoustic modelling of noise propagation During the present project period the computer code HAWCModal has been finished. The code computes the modal characteristics for a turbine as function of rotational speed. It is based on the structural modelling in the aeroelastic code HAWC and uses the same input files. The computed eigen frequencies are shown in a Campbell diagram and the corresponding modal forms can be shown graphically for an operating turbine. Finally, the structural damping is also computed by the code. HAWCModal is the basis for the stability analysis tool HAWCStab which is now under devel-opment. With HAWCStab the aeroelastic stability of a turbine can be analysed. The complex aerodynamics at three different blade tip shapes have been analysed with the three-dimensional CFD code EllipSys3D. The tip vortex was visualised and the lift and drag coef-ficients in the tip region were analysed in order to study the influence of the tip geometry on the performance and aerodynamic damping. An airfoil catalogue containing computations on 28 different airfoils for wind turbine applica-tion in comparison with experimental data has been developed and is available via the internet. Besides the main themes of the project as mentioned above there have been research

  8. Operating systems: Internals and design principles, 5th ed. William Stallings : Prentice Hall, 2005. ISBN: 0-13-147954-7

    OpenAIRE

    Molinari, Lía Hebe

    2007-01-01

    As a professor of the Operating Systems subject, I can say that for many years the book “Operating Systems Concepts” by Avi Silberschatz et al. was considered as the unquestionable number one in the subject’s bibliography. The book we are talking about now, the new edition of “Operating Systems” by William Stallings, is thought to be the possible replacement of the first one.

  9. The elastic transfer model of angular rate modulation in F1-ATPase stalling and controlled rotation experiments

    Science.gov (United States)

    Volkán-Kacsó, S.

    2017-06-01

    The recent experimental, theoretical and computational advances in the field of F1-ATPase single-molecule microscopy are briefly surveyed. The role of theory is revealed in the statistical analysis, interpretation and prediction of single-molecule experimental trajectories, and in linking them with atomistic simulations. In particular, a theoretical model of elastically coupled molecular group transfer is reviewed and a detailed method for its application in stalling and controlled rotation experiments is provided. It is shown how the model can predict, using previous experiments, the rates of ligand binding/release processes (steps) and their exponential dependence on rotor angle in these experiments. The concept of Brønsted slopes is reviewed in the context of the single-molecule experiments, and the rate versus rotor angle relations are explained using the elastic model. These experimental data are treated in terms of the effect of thermodynamic driving forces on the rates assuming that the rotor shaft is elastically coupled to stator ring subunits in which the steps occur. In the application of the group transfer model on an extended angular range processes leading up to the transfer are discussed. Implications for large-scale atomistic simulation are suggested for the treatment of torque-generating steps.

  10. Exploiting translational stalling peptides in an effort to extend azithromycin interaction within the prokaryotic ribosome nascent peptide exit tunnel.

    Science.gov (United States)

    Washington, Arren Z; Tapadar, Subhasish; George, Alex; Oyelere, Adegboyega K

    2015-08-15

    The ribosome is the primary protein synthesis machine in the cell and is a target for treatment of a variety of diseases including bacterial infection and cancer. The ribosomal peptide exit tunnel, the route of egress for the nascent peptide, is an inviting site for drug design. Toward a rational engagement of the nascent peptide components for the design of small molecule inhibitors of ribosome function, we designed and disclosed herein a set of N-10 indole functionalized azithromycin analogs. The indole moiety of these compounds is designed to mimic the translation stalling interaction of SecM W155 side-chain with the prokaryotic (Escherichia coli) ribosome A751 residue. Many of these N-10 functionalized compounds have enhanced translation inhibition activities against E. coli ribosome relative to azithromycin while a subset inhibited the growth of representative susceptible bacteria strains to about the same extent as azithromycin. Moreover, the inclusion of bovine serum in the bacterial growth media enhanced the anti-bacterial potency of the N-10 functionalized azithromycin analogs by as high as 10-fold. Published by Elsevier Ltd.

  11. A study of the drooped leading edge airfoil. [on wind tunnel models to reduce spin entry after stall

    Science.gov (United States)

    Anderson, J. D., Jr.; Barlow, J. B.

    1979-01-01

    Wind tunnel tests were conducted to examine various aspects of the drooped-leading edge airfoil which reduces the tendency for an airplane to enter a spin after stall occurs. Three baseline models were used for tests of two dimensional models: NACA 0015, 0014.6, and 0014.2. The 14.6% and 14.2% models were derived from NACA 0015 sections by increasing the chord and matching the profiles aft section. Force, balance data (lift, drag, pitching moment) were obtained for each model at a free-steam Reynold's number of 2.66 x 10 to the 6th power/m. In addition, oil flow visualization tests were performed at various angles of attack. An existing NACA 64 sub 1 A211 airfoil was used in a second series of tests. The leading edge flap was segmented in three parts which allowed various baseline/drooped leading edge configurations to be tested. Force balance and flow visualization tests were completer at chord Renolds numbers of 0.44 x 10 to the 6th power, 1.4 x 10 to the 6th power, and 2.11 x 10 to the 6th power. Test results are included.

  12. Using Nature-Based Rehabilitation to Restart a Stalled Process of Rehabilitation in Individuals with Stress-Related Mental Illness

    Directory of Open Access Journals (Sweden)

    Eva Sahlin

    2015-02-01

    Full Text Available After a period of decrease, sick leave in Sweden due to psychiatric diagnoses is on the increase. The lack of established rehabilitation programmes for patients with stress-related mental disorders (SRMD has opened up for the use of garden/nature in a multimodal rehabilitation context (Nature-Based Rehabilitation, NBR. Region Västra Götaland (VGR started an NBR to offer additional rehabilitation for its employees on long-term sick leave due to SRMD, where initial care had not been sufficient. The aim was to explore whether the mental health and well-being of NBR participants had improved at the end of the NBR and at three follow-ups, and to explore the development of sick leave and health care utilization according to the NBR model (n = 57 and an occupational health service (OHS model (n = 45. Self-assessment instruments for measuring burnout, depression, anxiety and wellbeing, and data from regional and national registers were used. Results showed decreased scores on burnout, depression and anxiety, and increased well-being scores and significantly reduced health care utilization in the NBR group. A large movement from ordinary sickness benefit to rehabilitation benefit was observed, which was not observed in the OHS group. The two groups were in different rehabilitation phases, which limited comparisons. The results point to beneficial effects of using NBR for this patient group and for enhancing a stalled rehabilitation process.

  13. Investigating dynamic stall, 3-D and rotational effects on wind turbine blades by means of an unsteady quasi-3D Navier-Stokes solver

    Energy Technology Data Exchange (ETDEWEB)

    Chaviaropoulos, P.K. [CRES-Center for Renewable Energy Sources, Pikermi Attiki (Greece)

    1997-08-01

    The blade element codes provide surprisingly accurate predictions of the aerodynamic loads provided that they are `fed` with proper lift and drag - incidence curves for the profiles mounted on the rotor blades. The evident question is how one can obtain such data. It is common experience that the use of the mostly available steady two-dimensional profile data may lead to serious discrepancies between measured and simulated loads. Although several correction techniques have been proposed as a remedy during the last years, from simplified dynamic stall models suitably tuned for wind turbines to 3-D correction schemes for profile data, the problem is by no means over-passed. Especially for the three-dimensional effects it seems that part of the difficulty is due to our limited understanding of the physical mechanism which is responsible for the extra loading of the inner part of the blades. Recognizing the importance of the above aspects two relevant Joule projects have been launched, the concluded `Dynamic Stall and 3-D Effects` JOU2-CT93-0345 and the ongoing `VISCWIND` JOR3-CT95-0007 project. Part of the activities in the first and all the activities in the second project are devoted to the identification and quantification of the dynamic stall and three-dimensional effects experienced by the wind turbine blades using Navier-Stokes computations. The contribution of CRES in these two projects is briefly presented in this paper. (EG)

  14. Quarterly Progress Report - Biological Monitoring Program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Adams, S. M.; Christensen, S. W.; Greeley, M.S. jr; McCracken, M.K.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth G. R.; Stewart, A. J.

    2001-01-19

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 National Security Complex (formerly the Oak Ridge Y-12 Plant). As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Complex protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Loar et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Complex on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Complex discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities. Monitoring is currently being conducted at five primary EFPC sites, although sites may be excluded or added depending upon the specific objectives of the various tasks. Criteria used in selecting the sites include: (1) location of sampling sites used in other studies, (2) known or suspected sources of downstream impacts, (3) proximity to U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR) boundaries, (4) concentration of mercury in the

  15. Caracterização do microambiente em secção transversal de um galpão do tipo "free-stall" orientado na direção norte-sul Environment characterization in transversal direction in a free-stall housing oriented to north-south direction

    Directory of Open Access Journals (Sweden)

    Alessandro T. Campos

    2004-04-01

    Full Text Available O trabalho teve o objetivo de caracterizar o microambiente climático das baias de um galpão de confinamento para gado leiteiro, modelo "free-stall", no sentido transversal da instalação. O "free-stall" é orientado na direção norte-sul, localizado em Marechal Cândido Rondon, região Oeste do Paraná, com capacidade para abrigar 40 vacas em lactação (40 baias. Visando à determinação do Índice de Temperatura do Globo e Umidade (ITGU e da Carga Térmica de Radiação (CTR, foram instalados quatro globos negros, no centro de baias dispostas no sent ido transversal, dispondo dois globos no lado oeste e dois globos no lado leste (separados pelo corredor de alimentação. Lateralmente ao galpão, no lado leste, havia vegetação a 4 m da instalação, que promovia sombreamento nas primeiras horas do dia. Pode-se concluir que, nas primeiras horas do dia, não há diferença significativa entre os valores de ITGU e CTR encontrados, indicando que o sombreamento, devido à vegetação, foi capaz de amenizar os efeitos da radiação solar. Às 17 h 30 min, verificou-se que há ocorrência de maiores valores, tanto de ITGU quanto de CTR, nas baias localizadas no lado oeste do "free-stall".This work aimed to characterize the microclimatic conditions of the stalls of a free-stall model confinement building for dairy cattle in the transversal direction of the installation. Free-stall building was oriented to north-south direction, located in Marechal Cândido Rondon, west of Paraná State -Brazil, with a capacity of 40 dairy cows (40 stalls. In order to determine the Black-Globe-Humidity Index (BGHI and Radiant Heat Load (RHL, four black globes were installed in the center of stalls disposed in the transversal direction, disposing two globes in the west side and two globes in the east side (separated by the feed alley. At the building sidelong, east side, there was a four meter distant vegetation, that promoted shading in the first hours of the day

  16. Floodplain Vegetation Productivity and Carbon Cycle Dynamics of the Middle Fork Flathead River of Northwest Montana

    Science.gov (United States)

    Oakins, A. J.; Kimball, J. S.; Relyea, S.; Stanford, J. A.

    2005-05-01

    River floodplains are vital natural features that store floodwaters, improve water quality, provide habitat, and create recreational opportunities. Recent studies have shown that strong interactions among flooding, channel and sediment movement, vegetation, and groundwater create a dynamic shifting habitat mosaic that promotes biodiversity and complex food webs. Multiple physical and environmental processes interact within these systems to influence forest productivity, including water availability, nutrient supply, soil texture, and disturbance history. This study is designed to quantify the role of groundwater depth and meteorology in determining spatial and temporal patterns of net primary productivity (NPP) within the Nyack floodplain of the Middle Fork Flathead River, Northwestern Montana. We examine three intensive field sites composed of mature, mixed deciduous and evergreen conifer forest with varying hydrologic and vegetative characteristics. We use a modified Biome-BGC ecosystem process model with field-collected data (LAI, increment growth cores, groundwater depth, vegetation sap-flow, and local meteorology) to describe the effects of floodplain groundwater dynamics on vegetation community structure, and carbon/nitrogen cycling. Initial results indicate that conifers are more sensitive than deeper-rooted deciduous species to variability in groundwater depth and meteorological conditions. Forest productivity also shows a non-linear response to groundwater depth. Sites with intermediate groundwater depths (0.2-0.5m) allow vegetation to maintain connectivity to groundwater over longer periods during the growing season, are effectively uncoupled from atmospheric constraints on photosynthesis, and generally have greater productivity. Shallow groundwater sites (<0.2m) are less productive due to the indirect effects of reduced soil aerobic decomposition and reduced plant available nitrogen.

  17. Human and ecological remediation goals for soil mercury at East Fork Poplar Creek, Oak Ridge, TN

    International Nuclear Information System (INIS)

    Zafran, F.A.; Cornaby, B.W.; Hadden, C.T.

    1995-01-01

    Mercury, used in the past production of enriched lithium by the Department of Energy, is the principal chemical of concern in the 14-mile floodplain of East Fork Poplar Creek (EFPC). SAIC has developed risk-based remediation goal options (RGOS) for mercury in EFPC soils to protect the most sensitive human receptors. The existing chronic oral RfD for mercury is based on exposure of laboratory species to mercuric chloride. However, speciation and leaching/availability studies (conducted by EPA EMSL and Oak Ridge National Laboratory) indicated less soluble and less toxic mercury species, principally mercuric sulfide, with measurable quantities of metallic mercury also present, predominate in EFPC floodplain soils. SAIC derived human health RGOs using deterministic and probabilistic methods and incorporated the probability density function for bioavailability of mercury species from leaching/availability data generated by ORNL. Monte Carlo simulation was used in uncertainty analysis and supported the derivation of a protective, but realistic risk-based remediation goal of 400 mg mercury/kg soil. For ecological risk assessment, RGOs were based on risks through food chains from contaminants in soil. The authors describe a terrestrial food-chain model of contaminant transfer to primary producers, first-order consumers, mid-level predators, and top-level predators. The model uses published toxicity data, site-specific contaminant concentrations, and bioaccumulation factors calculated from measured body burdens of floodplain organisms to compute RGOs for various combinations of exposure parameters. Model calculations show that under reasonably conservative conditions, mid-level predators have the highest exposures relative to dietary limits and, therefore, require the lowest soil-mercury RGOs. Mercury concentrations of ∼500 mg/kg are protective of the receptor populations exposed through food chains at this site

  18. New observations on the Middle Fork Eel River coal-bearing beds, Mendocino County, California, USA

    Energy Technology Data Exchange (ETDEWEB)

    Bartley, Russell H. [Mendocino County Museum, 400 East Commercial Street, Willits, CA 95490 (United States); Bartley, Sylvia E. [Noyo Hill House, 28953 Highway 20, Fort Bragg, CA 95437 (United States); Springer, David J. [College of the Redwoods-Mendocino Coast, 1211 Del Mar Drive, Fort Bragg, CA 95437 (United States); Erwin, Diane M. [Museum of Paleontology, 1101 Valley Life Sciences Building, University of California, Berkeley, CA 94720 (United States)

    2010-08-01

    Mid-19th century reports of ''immense'' coal outcrops in the Middle Fork Eel River (MFER) drainage near Round Valley in California's northern Coast Ranges fueled the early geological interest in this area, with mine development the primary focus of many studies. It was not until Samuel G. Clark's 1940 ''Geology of the Covelo District, Mendocino County, California,'' that the coal was placed in its regional geologic context and assigned to the Miocene, a determination that relied primarily on a Desmostylus hesperus molar found in shale overlying the coal and an associated equivocal, though Miocene-compatible, marine molluscan fauna. Our investigation of the MFER coal-bearing beds has provided new data from foraminifera, marine mollusks, fish remains, and the first reported fossil plants, which as a whole support Clark's Miocene age assignment. We also present an updated stratigraphy proposing under modern-day stratigraphic protocols that the informal name Sand Bank beds (SBb) be used in place of the Temblor Formation to refer to the SBb coal-bearing fluvial-marine unit. Analysis of the SBb stratigraphy and sedimentology reveals the presence of a fluvial system that flowed from a distal upland region southward toward the paleocoast of California. An abundant diverse palynoflora containing lycophytes, ferns, conifers, and mesic, thermophillic herbaceous and woody angiosperms indicates the drainage flowed through a coastal swampy forested bottomland and estuarine environment before emptying into a coastal basin. Presence of Taxodium-like wood, foliage, pollen, and other ''hydrophiles'' suggests the MFER coal was a local mire buried by the progradation of the SBb fluvial system during a regressive phase, an interpretation to be tested with future field work and detailed compositional analysis of the coal. (author)

  19. Speaking with forked tongues - Swedish public administration and the European employment strategy

    Directory of Open Access Journals (Sweden)

    Åsa Casula Vifell

    2009-07-01

    Full Text Available The aim of this paper is to understand how decision making processes within the EU comes to affect the structures for national policy making within the employment field. The paper addresses the question of how the process of writing new employment guidelines for the EES – European employment strategy, has affected the work of the Swedish public administration. Through applying a neo-institutionalist perspective, it contributes to the understanding of effects that the increased embededness of states, often characterized as Europeanization, invoke on national administrations. I argue that the way the process has been managed can be analyzed from an organizational perspective where conflicting demands on the Swedish state has led to a certain organization of the work activities. On the one hand, Swedish representatives have to act according to the norms of the European cooperation in order to be seen as a legitimate actor. On the other hand, EU and European influence on Swedish employment policy is not a legitimate concept at national level. In order to satisfy these two seemingly incompatible demands the organizing principle of decoupling is being used to create space for maneuvering for the administration. However, through participation at EU-level organizational identities are partly transformed which in time leads to a situation where changed practices are not met by changes in formal structures. As a consequence the Swedish representatives are in a manner ‘speaking with forked tongue’ and obscuring the new way in which policy making is conducted thus introducing democratic shortcomings in terms of transparency and accountability.

  20. Geomorphic Effects of Engineered Log Jams in River Restoration, Middle Fork John Day River

    Science.gov (United States)

    Duffin, J.; McDowell, P. F.

    2014-12-01

    The Middle Fork of the John Day River (MFJD) Intensively Monitored Watershed in eastern Oregon is a multi-phase restoration implementation and monitoring project. MFJD is a tributary to the Colombia and is part of one of the longest free flowing rivers systems in the continental United States. It is a gravel and cobble bed river with a drainage area of 2,100 km2. The river has endured extensive channel and floodplain degradation from years of channel alteration and straightening due to human influences including dredge mining, ranching, and farming. As part of the river restoration project on the MFJD, engineered log jams have been constructed to address many of the restoration goals including creating scour pools, inhibiting bank erosion, creating and maintaining a sinuous river planform, and increasing complexity of fish habitat. There is a need for more detailed understanding on ELJ channel morphologic effects and how site-specific characteristics and differences in log jam infrastructure interact to create the in-channel features over timescales longer than a few years. This study uses detailed channel bed topographic surveys collected either with a total station or RTK-GPS technology. Geomorphic change detection techniques are utilized to monitor topographic change under and around the 26 log structures in two different river reaches over a six to seven year period The log structures are often associated with deepening of pools as desired, but also some structures show sedimentation under the structure. Differences in the patterns will be assessed based on the design, location, and specific characteristics of the log structures; variables include number and placement of logs, volume of structure, location on meander bend, and sediment sizes.

  1. Groundwater and climate change: a sensitivity analysis for the Grand Forks aquifer, southern British Columbia, Canada

    Science.gov (United States)

    Allen, D. M.; Mackie, D. C.; Wei, M.

    The Grand Forks aquifer, located in south-central British Columbia, Canada was used as a case study area for modeling the sensitivity of an aquifer to changes in recharge and river stage consistent with projected climate-change scenarios for the region. Results suggest that variations in recharge to the aquifer under the different climate-change scenarios, modeled under steady-state conditions, have a much smaller impact on the groundwater system than changes in river-stage elevation of the Kettle and Granby Rivers, which flow through the valley. All simulations showed relatively small changes in the overall configuration of the water table and general direction of groundwater flow. High-recharge and low-recharge simulations resulted in approximately a +0.05 m increase and a -0.025 m decrease, respectively, in water-table elevations throughout the aquifer. Simulated changes in river-stage elevation, to reflect higher-than-peak-flow levels (by 20 and 50%), resulted in average changes in the water-table elevation of 2.72 and 3.45 m, respectively. Simulated changes in river-stage elevation, to reflect lower-than-baseflow levels (by 20 and 50%), resulted in average changes in the water-table elevation of -0.48 and -2.10 m, respectively. Current observed water-table elevations in the valley are consistent with an average river-stage elevation (between current baseflow and peak-flow stages). L'aquifère de Grand Forks, situé en Colombie britannique (Canada), a été utilisé comme zone d'étude pour modéliser la sensibilité d'un aquifère à des modifications de la recharge et du niveau de la rivière, correspondant à des scénarios envisagés de changement climatique dans cette région. Les résultats font apparaître que les variations de recharge de l'aquifère pour différents scénarios de changement climatique, modélisées pour des conditions de régime permanent, ont un impact sur le système aquifère beaucoup plus faible que les changements du niveau des

  2. A fuzzy logic pitch angle controller for power system stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, Clemens; Cronin, Tom; Sorensen, Poul [Wind Energy Department, Riso National Laboratory, PO Box 49, DK-4000 Roskilde, (Denmark); Jensen, Birgitte Bak [Institute of Energy Technology, Aalborg University, Pontoppidanstraede 101, DK-9220 Aalborg East, (Denmark)

    2006-07-12

    In this article the design of a fuzzy logic pitch angle controller for a fixed speed, active-stall wind turbine, which is used for power system stabilization, is presented. The system to be controlled, which is the wind turbine and the power system to which the turbine is connected, is described. The advantages of fuzzy logic control when applied to large-signal control of active-stall wind turbines are outlined. The general steps of the design process for a fuzzy logic controller, including definition of the controller inputs, set-up of the fuzzy rules and the method of defuzzification, are described. The performance of the controller is assessed by simulation, where the wind turbine's task is to dampen power system oscillations. In the scenario simulated for this work, the wind turbine has to ride through a transient short-circuit fault and subsequently contribute to the damping of the grid frequency oscillations that are caused by the transient fault. It is concluded that the fuzzy logic controller enables the wind turbine to dampen power system oscillations. It is also concluded that, owing to the inherent non-linearities in a wind turbine and the unpredictability of the whole system, the fuzzy logic controller is very suitable for this application. (Author).

  3. The effect of real-time vibrotactile feedback delivered through an augmented fork on eating rate, satiation, and food intake.

    Science.gov (United States)

    Hermans, Roel C J; Hermsen, Sander; Robinson, Eric; Higgs, Suzanne; Mars, Monica; Frost, Jeana H

    2017-06-01

    Eating rate is a basic determinant of appetite regulation, as people who eat more slowly feel sated earlier and eat less. Without assistance, eating rate is difficult to modify due to its automatic nature. In the current study, participants used an augmented fork that aimed to decelerate their rate of eating. A total of 114 participants were randomly assigned to the Feedback Condition (FC), in which they received vibrotactile feedback from their fork when eating too fast (i.e., taking more than one bite per 10 s), or a Non-Feedback Condition (NFC). Participants in the FC took fewer bites per minute than did those in the NFC. Participants in the FC also had a higher success ratio, indicating that they had significantly more bites outside the designated time interval of 10 s than did participants in the NFC. A slower eating rate, however, did not lead to a significant reduction in the amount of food consumed or level of satiation. These findings indicate that real-time vibrotactile feedback delivered through an augmented fork is capable of reducing eating rate, but there is no evidence from this study that this reduction in eating rate is translated into an increase in satiation or reduction in food consumption. Overall, this study shows that real-time vibrotactile feedback may be a viable tool in interventions that aim to reduce eating rate. The long-term effectiveness of this form of feedback on satiation and food consumption, however, awaits further investigation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Perdas econômicas ocasionadas pelas enfermidades podais em vacas leiteiras confinadas em sistema free stall Economic losses caused by sequels of lameness in free-stall-housed dairy cows

    Directory of Open Access Journals (Sweden)

    R.C. Souza

    2006-12-01

    Full Text Available Avaliaram-se 55 casos clínicos de manqueira em um rebanho de 100 vacas em lactação confinadas em sistema de free stall, durante um ano. As afecções mais observadas foram abscessos de sola e talão, úlcera de sola e dermatite digital que representaram 87,3% (48/55 das ocorrências. O tratamento empregado mostrou-se satisfatório com recuperação de todos os animais tratados com 24,5 dias, em média, sem ocorrência de descarte. O custo com tratamento e redução na produção de leite foi de US$95.80/vaca, o que representou US$52.69 por vaca alojada/ano. Quando se computaram as perdas reprodutivas e com mastite, obtiveram-se US$227.94 adicionais em vaca com problema de manqueira. O custo adicional anual total no rebanho decorrente de seqüelas de manqueira foi de US$12,536.70, que representou US$125.36 por vaca alojada/ano. O período de serviço e o número de serviços por concepção em vacas com problemas de manqueira e normais foram 266 e 200,5 dias e 4,3 e 3,3 serviços, respectivamente. As incidências de mastite e metrite na mesma ordem de citação anterior foram 60% e 25% e 29% e 12,5%.Fifty-five clinical cases of lameness were evaluated in 100 lactating cows housed in a free-stall system during one year. The most observed affections were sole and heel abscesses, sole ulcers and digital dermatitis that accounted for 87.3% (48/55 of the occurrences. The treated cows showed satisfactory recovery (24.5 average days without culling. The total individual cost including treatment and reduction of milk production was US$95.80/cow or US$52.69 per housed cow/year. When reproductive losses and mastitis were considered an additional cost of US$227.94 per lameness cow was estimated. The total additional annual cost from sequels of lameness was US$12.536.70 or US$152.36 per housed cow/year. The number of days open and the number of services per conception in lameness and normal cows were, respectively, 266 and 200.5 days and 4.3 and 3

  5. Environmental compliance plan for the Lower East Fork Poplar Creek Remedial Action Project at Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-07-01

    Remedial action for Lower East Fork Poplar Creek, as defined by the Record of Decision, requires that soil contaminated with >400 ppM mercury be excavated and disposed. Based on the remediation goal, soil will be excavated from areas located at the NOAA site and the Bruner site and disposed at the Industrial Landfill V at the Y-12 Plant. Objective is to minimize the risk to human health and the environment from contaminated soil in the lower EFPC floodplain pursuant to CERCLA and the Federal Facility Agreement (DOE 1992)

  6. Environmental compliance plan for the Lower East Fork Poplar Creek Remedial Action Project at Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    Remedial action for Lower East Fork Poplar Creek, as defined by the Record of Decision, requires that soil contaminated with >400 ppM mercury be excavated and disposed. Based on the remediation goal, soil will be excavated from areas located at the NOAA site and the Bruner site and disposed at the Industrial Landfill V at the Y-12 Plant. Objective is to minimize the risk to human health and the environment from contaminated soil in the lower EFPC floodplain pursuant to CERCLA and the Federal Facility Agreement (DOE 1992).

  7. Flood-inundation maps for an 8.9-mile reach of the South Fork Little River at Hopkinsville, Kentucky

    Science.gov (United States)

    Lant, Jeremiah G.

    2013-01-01

    Digital flood-inundation maps for an 8.9-mile reach of South Fork Little River at Hopkinsville, Kentucky, were created by the U.S. Geological Survey (USGS) in cooperation with the City of Hopkinsville Community Development Services. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at South Fork Little River at Highway 68 By-Pass at Hopkinsville, Kentucky (station no. 03437495). Current conditions for the USGS streamgage may be obtained online at the USGS National Water Information System site (http://waterdata.usgs.gov/nwis/inventory?agency_code=USGS&site_no=03437495). In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often co-located at USGS streamgages. The forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the South Fork Little River reach by using HEC-RAS, a one-dimensional step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the most current (2012) stage-discharge relation at the South Fork Little River at Highway 68 By-Pass at Hopkinsville, Kentucky, streamgage and measurements collected during recent flood events. The calibrated model was then used to calculate 13 water-surface profiles for a sequence of flood stages, most at 1-foot intervals, referenced to the streamgage datum and ranging from a stage near bank full to the estimated elevation of the 1.0-percent annual exceedance

  8. Scanning thermal microscopy based on a quartz tuning fork and a micro-thermocouple in active mode (2ω method)

    Energy Technology Data Exchange (ETDEWEB)

    Bontempi, Alexia; Nguyen, Tran Phong; Salut, Roland; Thiery, Laurent; Teyssieux, Damien; Vairac, Pascal [FEMTO-ST Institute UMR 6174, Université de Franche-Comté, CNRS, ENSMM, UTBM, 15B Avenue des Montboucons, F-25030 Besançon (France)

    2016-06-15

    A novel probe for scanning thermal microscope using a micro-thermocouple probe placed on a Quartz Tuning Fork (QTF) is presented. Instead of using an external deflection with a cantilever beam for contact detection, an original combination of piezoelectric resonator and thermal probe is employed. Due to a non-contact photothermal excitation principle, the high quality factor of the QTF allows the probe-to-surface contact detection. Topographic and thermal scanning images obtained on a specific sample points out the interest of our system as an alternative to cantilevered resistive probe systems which are the most spread.

  9. Baseline and Postremediation Monitoring Program Plan for the Lower East Fork Poplar Creek operable unit, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    This report was prepared in accordance with CERCLA requirements to present the plan for baseline and postremediation monitoring as part of the selected remedy. It provides the Environmental Restoration Program with information about the requirements to monitor for soil and terrestrial biota in the Lower East Fork Poplar Creek (LEFPC) floodplain; sediment, surface water, and aquatic biota in LEFPC; wetland restoration in the LEFPC floodplain; and human use of shallow groundwater wells in the LEFPC floodplain for drinking water. This document describes the monitoring program that will ensure that actions taken under Phases I and II of the LEFPC remedial action are protective of human health and the environment.

  10. Characterization and 3D reservoir modelling of fluvial sandstones of the Williams Fork Formation, Rulison Field, Piceance Basin, Colorado, USA

    International Nuclear Information System (INIS)

    Pranter, Matthew J; Vargas, Marielis F; Davis, Thomas L

    2008-01-01

    This study describes the stratigraphic characteristics and distribution of fluvial deposits of the Upper Cretaceous Williams Fork Formation in a portion of Rulison Field and addresses 3D geologic modelling of reservoir sand bodies and their associated connectivity. Fluvial deposits include isolated and stacked point-bar deposits, crevasse splays and overbank (floodplain) mudrock. Within the Williams Fork Formation, the distribution and connectivity of fluvial sandstones significantly impact reservoir productivity and ultimate recovery. The reservoir sandstones are primarily fluvial point-bar deposits interbedded with shales and coals. Because of the lenticular geometry and limited lateral extent of the reservoir sandstones (common apparent widths of ∼500–1000 ft; ∼150–300 m), relatively high well densities (e.g. 10 acre (660 ft; 200 m) spacing) are often required to deplete the reservoir. Heterogeneity of these fluvial deposits includes larger scale stratigraphic variability associated with vertical stacking patterns and structural heterogeneities associated with faults that exhibit lateral and reverse offsets. The discontinuous character of the fluvial sandstones and lack of distinct marker beds in the middle and upper parts of the Williams Fork Formation make correlation between wells tenuous, even at a 10 acre well spacing. Some intervals of thicker and amalgamated sandstones within the middle and upper Williams Fork Formation can be correlated across greater distances. To aid correlation and for 3D reservoir modelling, vertical lithology proportion curves were used to estimate stratigraphic trends and define the stratigraphic zonation within the reservoir interval. Object-based and indicator-based modelling methods have been applied to the same data and results from the models were compared. Results from the 3D modelling indicate that sandstone connectivity increases with net-to-gross ratio and, at lower net-to-gross ratios (<30%), differences exist in

  11. Scanning thermal microscopy based on a quartz tuning fork and a micro-thermocouple in active mode (2ω method)

    International Nuclear Information System (INIS)

    Bontempi, Alexia; Nguyen, Tran Phong; Salut, Roland; Thiery, Laurent; Teyssieux, Damien; Vairac, Pascal

    2016-01-01

    A novel probe for scanning thermal microscope using a micro-thermocouple probe placed on a Quartz Tuning Fork (QTF) is presented. Instead of using an external deflection with a cantilever beam for contact detection, an original combination of piezoelectric resonator and thermal probe is employed. Due to a non-contact photothermal excitation principle, the high quality factor of the QTF allows the probe-to-surface contact detection. Topographic and thermal scanning images obtained on a specific sample points out the interest of our system as an alternative to cantilevered resistive probe systems which are the most spread.

  12. Scanning thermal microscopy based on a quartz tuning fork and a micro-thermocouple in active mode (2ω method).

    Science.gov (United States)

    Bontempi, Alexia; Nguyen, Tran Phong; Salut, Roland; Thiery, Laurent; Teyssieux, Damien; Vairac, Pascal

    2016-06-01

    A novel probe for scanning thermal microscope using a micro-thermocouple probe placed on a Quartz Tuning Fork (QTF) is presented. Instead of using an external deflection with a cantilever beam for contact detection, an original combination of piezoelectric resonator and thermal probe is employed. Due to a non-contact photothermal excitation principle, the high quality factor of the QTF allows the probe-to-surface contact detection. Topographic and thermal scanning images obtained on a specific sample points out the interest of our system as an alternative to cantilevered resistive probe systems which are the most spread.

  13. Baseline and Postremediation Monitoring Program Plan for the Lower East Fork Poplar Creek operable unit, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-04-01

    This report was prepared in accordance with CERCLA requirements to present the plan for baseline and postremediation monitoring as part of the selected remedy. It provides the Environmental Restoration Program with information about the requirements to monitor for soil and terrestrial biota in the Lower East Fork Poplar Creek (LEFPC) floodplain; sediment, surface water, and aquatic biota in LEFPC; wetland restoration in the LEFPC floodplain; and human use of shallow groundwater wells in the LEFPC floodplain for drinking water. This document describes the monitoring program that will ensure that actions taken under Phases I and II of the LEFPC remedial action are protective of human health and the environment

  14. Twelve Years of Monitoring Phosphorus and Suspended-Solids Concentrations and Yields in the North Fork Ninnescah River above Cheney Reservoir, South-Central Kansas 1997-2008

    Science.gov (United States)

    Stone, Mandy L.; Graham, Jennifer L.; Ziegler, Andrew C.

    2009-01-01

    Cheney Reservoir, located on the North Fork Ninnescah River in south-central Kansas, is the primary water supply for the city of Wichita and an important recreational resource. Concerns about taste-and-odor occurrences in Cheney Reservoir have drawn attention to potential pollutants, including total phosphorus (TP) and total suspended solids (TSS). July 2009 was the 15th anniversary of the establishment of the Cheney Reservoir Watershed pollution management plan. The U.S. Geological Survey (USGS), in cooperation with the city of Wichita, has collected water-quality data in the basin since 1996, and has monitored water quality continuously on the North Fork Ninnescah River since 1998. This fact sheet describes 12 years (1997-2008) of computed TP and TSS data and compares these data with water-quality goals for the North Fork Ninnescah River, the main tributary to Cheney Reservoir.

  15. Integrated Outcrop and Subsurface Studies of the Interwell Environment of Carbonate Reservoirs: Clear Fork (Leonaradian Age) Reservoirs, West Texas and New Mexico

    International Nuclear Information System (INIS)

    Lucia, F.J.; Ruppel, S.C.

    2001-01-01

    Characterization of cycle and facies architecture on lower Clear Fork and lowermost upper Clear Fork equivalent outcrops in Apache Canyon of Sierra Diablo was complete. The focus of detailed study in Apache Canyon has been the upper Clear Fork section because this interval contains the productive interval in South Wasson field, the preliminary subsurface study area. Parts of three high-frequency sequences (HFS), each 60 to 100 ft thick, are present on the south wall of Apache Canyon. HFS's display an upper-deepening or backstepping pattern associated with longer-term sea level rise. Each HFS is composed of upward-shallowing cycles whose thickness, facies composition, and continuity vary within and between HFS's

  16. Isolation of the mouse (MFH-1) and human (FKHL14) mesenchyme fork head-1 genes reveals conservation of their gene and protein structures

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Naoyuki; Iida, Kiyoshi; Yang, Xiao-Li [Akita Univ. School of Medicine (Japan)] [and others

    1997-05-01

    The very recently found evolutionarily conserved DNA-binding domain of 100 amino acids, termed the fork head domain, emerged from a sequence comparison of the rat hepatocyte transcription factor HNF-3{alpha} and the homeotic gene fork head of Drosophila. We previously isolated a new member of this family, the mesenchyme fork head-1 (MFH-1) gene, which is expressed in developing mesenchyme. Here we describe the isolation of the mouse (MFH-1) and human (FKHL14) chromosomal MFH-1 genes and the determination of the gene and protein structures of MFH-1. We found that the MFH-1 gene has no introns and that the identity of the amino acid sequences of mouse and human MFH-1 proteins is 94%. We also investigated the transcriptional activity of the mouse and human MFH-1 proteins and found that both proteins act as positive transactivators. 31 refs., 3 figs.

  17. South Fork Tolt River Hydroelectric Project : Adopted Portions of a 1987 Federal Energy Regulatory Commission`s Final Environmental Impact Statement.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1992-07-01

    The South Fork Tolt River Hydroelectric Project that world produce 6.55 average megawatts of firm energy per year and would be sited in the Snohomish River Basin, Washington, was evaluated by the Federal Energy Regulatory commission (FERC) along with six other proposed projects for environmental effects and economic feasibility Based on its economic analysis and environmental evaluation of the project, the FERC staff found that the South Fork Tolt River Project would be economically feasible and would result in insignificant Impacts if sedimentation issues could be resolved. Upon review, the BPA is adopting portions of the 1987 FERC FEIS that concern the South Fork Tolt River Hydroelectric Project and updating specific sections in an Attachment.

  18. Macroeconomic stability

    DEFF Research Database (Denmark)

    Jespersen, Jesper

    2004-01-01

    It is demonstrated that full employment and sustainable development not necessarily are conflicting goals. On the other hand macroeconomic stability cannot be obtained without a deliberate labour sharing policy and a shift in the composition of private consumption away from traditional material...

  19. Impact of Load Behavior on Transient Stability and Power Transfer Limitations

    DEFF Research Database (Denmark)

    Gordon, Mark

    2009-01-01

    This paper presents utility based load modeling practices and explores the interaction between loads and the power system and the effect of the interaction on transient stability and power transfer limitations. The effect of load composition is investigated at major load centers together...... power systems are presented. A series of examples illustrate the results for which stable and unstable system responses are obtained....... with the impact on rotor angle excursions of large scale generators during the transient and post-transient period. Responses of multi-induction motor stalling are also considered for different fault clearances in the system. Findings of the investigations carried out on the Eastern Australian interconnected...

  20. Evaluating the effectiveness of floodplain restoration on the North Fork John Day River, Northeast Oregon, USA

    Science.gov (United States)

    Clifton, C. F.; Blanton, P.; Long, W.; Walterman, M. T.; McDowell, P. F.; Maus, P.

    2007-12-01

    Over the last decade hundreds of river restoration projects intended to maintain, protect, and restore watersheds, rivers, and habitat for native species in the Pacific Northwest have been implemented. By some counts, investment in watershed restoration exceeds hundreds of millions of dollars annually yet the effectiveness of these efforts remains an elusive question (Roni, 2005). Remote sensing and GIS technologies show great promise for large-scale river monitoring, however most natural resource organizations who implement these projects have limited budget and staff and would benefit from simple, low cost monitoring techniques that use readily available imagery. We used 1:24000 digitized orthorectified resource imagery from 1995, and National Agriculture Imagery Program (NAIP) digital orthophotography from 2005 to assess the effectiveness of floodplain restoration on a 16 km reach of the North Fork John Day River. Between 1993 and 1997 this section was restored by mechanically removing, reshaping, and revegetating cobble-boulder tailings piles left from dredge mining. The project was intended to directly improve floodplain function (i.e. inundation, riparian habitat) and indirectly improve instream habitat (pools, spawning) by reconnecting the active river channel with a reconstructed floodplain surface. Project effectiveness was not well documented initially in terms of quantifying floodplain functional area improvement or channel condition and response at the river-reach scale. Our objectives were to field-verify remote sensing measurements of response variables to test the applicability of available remote sensing imagery for project effectiveness monitoring, and to quantify adjustment in river response variables, using a "before-after" case study approach. Bracketing restoration activities with 1995 and 2000 imagery, we developed and tested methods for acquisition and processing of digital imagery and identified a core set of response variables to sample

  1. A transcription fork model for Pol IV and Pol V-dependent RNA-directed DNA methylation.

    Science.gov (United States)

    Pikaard, C S; Haag, J R; Pontes, O M F; Blevins, T; Cocklin, R

    2012-01-01

    In Arabidopsis thaliana, nuclear multisubunit RNA polymerase IV (Pol IV) and RNA-DEPENDENT RNA POLYMERASE 2 (RDR2) are required for the biogenesis of 24-nucleotide small interfering RNAs (siRNAs) that direct DNA methylation and transcriptional silencing at target loci transcribed by nuclear multisubunit RNA polymerase V (Pol V). Pol IV and RDR2 physically associate and RDR2's polymerase activity in vitro is dependent on Pol IV. RDR2 transcription of nascent Pol IV transcripts might result in discontinuous second strands, analogous to lagging-strand Okazaki fragments generated during DNA replication. In vitro, Pol V is unable to displace nontemplate DNA during transcriptional elongation. This suggests a need for DNA duplex unwinding by helper proteins, perhaps analogous to the helicase-mediated duplex unwinding that occurs at replication forks to enable leading strand synthesis by DNA polymerase ε. A multiprotein complex (DRD1, DMS3, DMS11, RDM1) known to enable Pol V transcription might facilitate duplex unwinding via ATP-dependent DNA translocase, single-stranded DNA binding, and cohesin-like strand capture activities. These considerations are discussed and incorporated into a "transcription fork" model for Pol IV and Pol V-dependent RNA-directed DNA methylation.

  2. Best management practices plan for the Lower East Fork Poplar Creek remedial action project, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-08-01

    The U.S. Department of Energy (DOE) has three major operating facilities on the DOE Oak Ridge Reservation (ORR) in Oak Ridge, Tennessee: the Oak Ridge Y-12 Plant, the K-25 Site, and the Oak Ridge National Laboratory (ORNL) managed by Lockheed Martin Environmental Research Corporation. All facilities are managed by Lockheed Martin Energy Systems, Incorporated (Energy Systems) for the DOE. The Y-12 Plant is adjacent to the city of Oak Ridge and is also upstream from Oak Ridge along East Fork Poplar Creek. The portion of the creek downstream from the Y-12 Plant is Lower East Fork Poplar Creek (LEFPC). This project will remove mercury-contaminated soils from the LEFPC floodplain, transport the soils to Industrial Landfill V (ILF-V), and restore any affected areas. This project contains areas that were designated in 1989 as a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) site. The site includes DOE property and portions of commercial, residential, agricultural, and miscellaneous areas within the city of Oak Ridge

  3. Helicase and polymerase move together close to the fork junction and copy DNA in one-nucleotide steps

    Science.gov (United States)

    Pandey, Manjula; Patel, Smita S.

    2014-01-01

    SUMMARY By simultaneously measuring DNA synthesis and dNTP hydrolysis, we show that T7 DNA polymerase and T7 gp4 helicase move in sync during leading strand synthesis taking one-nucleotide steps and hydrolyzing one dNTP per base-pair unwound-copied. The cooperative catalysis enables the helicase and polymerase to move at a uniformly fast rate without GC-dependency or idling with futile NTP hydrolysis. We show that the helicase and polymerase are located close to the replication fork junction. This architecture enables the polymerase to use its strand-displacement synthesis to increase the unwinding rate while the helicase aids this process by translocating along single-stranded DNA and trapping the unwound bases. Thus, in contrast to the helicase-only unwinding model, our results suggest a new model where the helicase and polymerase are moving in one-nucleotide steps and DNA synthesis drives fork unwinding and a role of the helicase is to trap the unwound bases and prevent DNA reannealing. PMID:24630996

  4. Quality Assurance Plan for the Upper East Fork Poplar Creek Characterization Area, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-12-01

    This quality assurance plan summarizes requirements for conducting work on the Upper East 9 Fork Poplar Creek (UEFPC) Characterization Area (CA). The reader is referred to the Expanded Task Work Agreement for Upper East Fork Poplar Creek Characterization Area, Remedial Investigation/Feasibility Study (RI/FS) for details regarding the activities, roles, and responsibilities summarized here. UEFPC is designated a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) site and thus requires a remedial investigation (RI) and a feasibility study (FS). The RI objectives are to evaluate the nature and extent of known and suspected contaminates, to provide data to perform baseline ecological and human health risk assessments, and to support development and evaluation of remedial alternatives for the FS,. Existing data will be used as much as possible. Additional sampling may be required to fill data gaps. The goal of the RI is to prioritize the major sources of contaminants to exit pathways and to understand their characteristics for risk characterization and development of remedial alternatives. The FS objectives are to investigate technologies and develop and evaluate alternatives based on 2031 CERCLA guidance

  5. DNA polymerase η modulates replication fork progression and DNA damage responses in platinum-treated human cells

    Science.gov (United States)

    Sokol, Anna M.; Cruet-Hennequart, Séverine; Pasero, Philippe; Carty, Michael P.

    2013-11-01

    Human cells lacking DNA polymerase η (polη) are sensitive to platinum-based cancer chemotherapeutic agents. Using DNA combing to directly investigate the role of polη in bypass of platinum-induced DNA lesions in vivo, we demonstrate that nascent DNA strands are up to 39% shorter in human cells lacking polη than in cells expressing polη. This provides the first direct evidence that polη modulates replication fork progression in vivo following cisplatin and carboplatin treatment. Severe replication inhibition in individual platinum-treated polη-deficient cells correlates with enhanced phosphorylation of the RPA2 subunit of replication protein A on serines 4 and 8, as determined using EdU labelling and immunofluorescence, consistent with formation of DNA strand breaks at arrested forks in the absence of polη. Polη-mediated bypass of platinum-induced DNA lesions may therefore represent one mechanism by which cancer cells can tolerate platinum-based chemotherapy.

  6. Fatigue strength of a fork-pin equivalent coupling in terms of the local strain energy density

    International Nuclear Information System (INIS)

    Berto, F.; Croccolo, D.; Cuppini, R.

    2008-01-01

    The fork-pin coupling of the front suspension of a motorbike is very important for the reliability and the safety of the entire vehicle. One of the more important causes of failure of the component is fatigue under fully reversed bending load. In this work, the fatigue behaviour of fork-pin equivalent couplings made of 39NiCrMo3 steel is analysed by means of simplified specimens obtained by the interference of a cylindrical pin in a hollow cylinder reproducing the same static stresses present on the contact surfaces of the real component. The contact of the two bodies is modelled by means of Ansys 9.0 and the stress field due to the interference is analysed and compared with that obtained by a strain gauge located on the external surface of the equivalent hub during the press-fit operation. By means of the same three-dimensional model, the local strain energy density (SED) averaged in a control volume, defined under mode I loading and surrounding the critical zone of the pin, is evaluated to summarize all fatigue strength data. The data, expressed in terms of the local energy, fall in the same scatter band with some other new data from plain and V-notched specimens made of the same material subjected to tension loading. Altogether about 60 new fatigue results are now available and presented in the paper

  7. Best management practices plan for the Lower East Fork Poplar Creek remedial action project, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The U.S. Department of Energy (DOE) has three major operating facilities on the DOE Oak Ridge Reservation (ORR) in Oak Ridge, Tennessee: the Oak Ridge Y-12 Plant, the K-25 Site, and the Oak Ridge National Laboratory (ORNL) managed by Lockheed Martin Environmental Research Corporation. All facilities are managed by Lockheed Martin Energy Systems, Incorporated (Energy Systems) for the DOE. The Y-12 Plant is adjacent to the city of Oak Ridge and is also upstream from Oak Ridge along East Fork Poplar Creek. The portion of the creek downstream from the Y-12 Plant is Lower East Fork Poplar Creek (LEFPC). This project will remove mercury-contaminated soils from the LEFPC floodplain, transport the soils to Industrial Landfill V (ILF-V), and restore any affected areas. This project contains areas that were designated in 1989 as a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) site. The site includes DOE property and portions of commercial, residential, agricultural, and miscellaneous areas within the city of Oak Ridge.

  8. Growth discordance of monoamniotic twin because of difference of cords diameter in forked umbilical cord: Case report.

    Science.gov (United States)

    Guo, Yongbing; Sun, Yu; Yang, Huixia

    2017-09-01

    A case of monochorionic-monoamniotic (MCMA) twin pregnancy with growth discordance because of difference of cord diameter in forked umbilical cord is reported.MCMA twins were diagnosed at 12 weeks of gestation and twin growth discordance was considered during the follow-up twice-weekly visits to the ultrasound and prenatal care units. The pregnancy was terminated at 34 weeks. Two live female babies weighing 2510 g and 1940 g were delivered. Examination of placenta and umbilical cords after birth showed that the 2 cords merged into a conjoint cord 1 cm from insertion to the placenta (forked umbilical cord). Placental color injection showed that the 2 fetuses shared the same placenta area. The diameters of the 2 cords were significantly different (1.5 vs 0.8 cm). This caused an unequal distribution of blood and nutrients, which is the real reason of twin growth discordance in this case.This case reveals that the diameter discordance of cords can be an important factor for twin growth discordance. Few relevant cases have previously been reported. Cords diameter measurement is suggested for ultrasound surveillance of twin growth discordance.

  9. The role of psychological determinants and demographic factors in consumer demand for farm-to-fork traceability systems.

    Science.gov (United States)

    Myae, Aye Chan; Goddard, Ellen; Aubeeluck, Ashwina

    2011-01-01

    Traceability systems are an important tool (1) for tracking, monitoring, and managing product flows through the supply chain for better efficiency and profitability of suppliers, and (2) to improve consumer confidence in the face of serious food safety incidents. After the global bovine spongiform encephalopathy (BSE) crisis affected producers, consumers, trade, and the health status of animals and humans, new systems to help confirm the status of cattle products along the supply chain from farm to fork were implemented in many countries (Trautman et al. 2008 ). In this study, people's overall food safety beliefs are explored with the main objective of measuring the link between their food safety beliefs and their attitudes toward traceability. A comparison is made among English-speaking Canadians, French-speaking Canadians, and Japanese consumers. In the study, an Internet-based survey was used to collect data from nationally representative samples of the population in Canada-English (1275), Canada-French (343), and Japanese (1940) in the summer of 2009. Respondents' interests in traceability systems are clearly linked to their sense that the industry is primarily responsible for any food safety outbreaks. Moreover, it is clear that certain segments of the population in all samples feel strongly about the importance of farm to fork traceability in beef; thus, policymakers may wish to consider extending traceability beyond the point of slaughter as a way of encouraging beef sales in Canada.

  10. Helicase and Polymerase Move Together Close to the Fork Junction and Copy DNA in One-Nucleotide Steps

    Directory of Open Access Journals (Sweden)

    Manjula Pandey

    2014-03-01

    Full Text Available By simultaneously measuring DNA synthesis and dNTP hydrolysis, we show that T7 DNA polymerase and T7 gp4 helicase move in sync during leading-strand synthesis, taking one-nucleotide steps and hydrolyzing one dNTP per base-pair unwound/copied. The cooperative catalysis enables the helicase and polymerase to move at a uniformly fast rate without guanine:cytosine (GC dependency or idling with futile NTP hydrolysis. We show that the helicase and polymerase are located close to the replication fork junction. This architecture enables the polymerase to use its strand-displacement synthesis to increase the unwinding rate, whereas the helicase aids this process by translocating along single-stranded DNA and trapping the unwound bases. Thus, in contrast to the helicase-only unwinding model, our results suggest a model in which the helicase and polymerase are moving in one-nucleotide steps, DNA synthesis drives fork unwinding, and a role of the helicase is to trap the unwound bases and prevent DNA reannealing.

  11. [Management of the dry and transition periods of dairy cattle in free stall housing systems in Lower Saxony. Part 1: Farm management. Teil 1: Betriebsmanagement].

    Science.gov (United States)

    Oetting-Neumann, Pamela; Hoedemaker, Martina

    2017-10-17

    Describing husbandry and management of dairy cows during the dry and transition periods on farms of different sizes in Lower Saxony, Germany. A total of 51 dairy farms were visited and asked via questionnaire about the husbandry and management in the following categories: general operating data, stable and husbandry of milking cows, dry cows, transition cows and the youngstock, pasture management, feeding, health data and prophylactic treatments. In addition, during a farm inspection, data on cow comfort were collected. German Holstein was the predominant breed on the dairy farms. Most cattle were kept in three-rowed free-stall housing systems (74%) with straw bedding (47%) without division in productivity groups (59%). The dry cows were most frequently separated in two groups (68%) in free-stall housing systems (68%). The heifers were similarly mainly kept in free-stall housing systems (67%) and were mostly separated according to their reproductive status (74%). On 29% of the farms, pasture grazing was not practiced at any time. On 80% of the farms, cows were fed a mixed ration with computerized concentrate supplementation and on 68% of the farms biphasic dry cow diets were used. The most frequently stated health problems were of the limb and claw (61%). Prophylaxis of ketosis was practiced on 21% of the farms and milk-fever prophylaxis on 12% of the farms, both for each individual cow around calving. Husbandry and management on farms differ widely and are still in need of optimization with respect to barn concepts, implementation of production groups and feeding, as well as veterinary consultation with respect to health problems and prophylactic measures.

  12. Jordan's 2002 to 2012 Fertility Stall and Parallel USAID Investments in Family Planning: Lessons From an Assessment to Guide Future Programming.

    Science.gov (United States)

    Spindler, Esther; Bitar, Nisreen; Solo, Julie; Menstell, Elizabeth; Shattuck, Dominick

    2017-12-28

    Health practitioners, researchers, and donors are stumped about Jordan's stalled fertility rate, which has stagnated between 3.7 and 3.5 children per woman from 2002 to 2012, above the national replacement level of 2.1. This stall paralleled United States Agency for International Development (USAID) funding investments in family planning in Jordan, triggering an assessment of USAID family planning programming in Jordan. This article describes the methods, results, and implications of the programmatic assessment. Methods included an extensive desk review of USAID programs in Jordan and 69 interviews with reproductive health stakeholders. We explored reasons for fertility stagnation in Jordan's total fertility rate (TFR) and assessed the effects of USAID programming on family planning outcomes over the same time period. The assessment results suggest that the increased use of less effective methods, in particular withdrawal and condoms, are contributing to Jordan's TFR stall. Jordan's limited method mix, combined with strong sociocultural determinants around reproduction and fertility desires, have contributed to low contraceptive effectiveness in Jordan. Over the same time period, USAID contributions toward increasing family planning access and use, largely focused on service delivery programs, were extensive. Examples of effective initiatives, among others, include task shifting of IUD insertion services to midwives due to a shortage of female physicians. However, key challenges to improved use of family planning services include limited government investments in family planning programs, influential service provider behaviors and biases that limit informed counseling and choice, pervasive strong social norms of family size and fertility, and limited availability of different contraceptive methods. In contexts where sociocultural norms and a limited method mix are the dominant barriers toward improved family planning use, increased national government investments

  13. Faunal assemblages and multi-scale habitat patterns in headwater tributaries of the South Fork Trinity River - an unregulated river embedded within a multiple-use landscape

    Science.gov (United States)

    H. H. Jr. Welsh; J. J. G. R. Hodgson; J. M. Emlen. Duda

    2010-01-01

    Headwaters can represent 80% of stream kilometers in a watershed, and they also have unique physical and biological properties that have only recently been recognized for their importance in sustaining healthy functioning stream networks and their ecological services. We sampled 60 headwater tributaries in the South Fork Trinity River, a 2,430 km2...

  14. Water-quality, bed-sediment, and biological data (October 2009 through September 2010) and statistical summaries of data for streams in the Clark Fork basin, Montana

    Science.gov (United States)

    Dodge, Kent A.; Hornberger, Michelle I.; Dyke, Jessica

    2012-01-01

    Water, bed sediment, and biota were sampled in streams from Butte to near Missoula, Montana, as part of a monitoring program in the upper Clark Fork basin. The sampling program was conducted by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency to characterize aquatic resources in the Clark Fork basin of western Montana, with emphasis on trace elements associated with historic mining and smelting activities. Sampling sites were located on the Clark Fork and selected tributaries. Water samples were collected periodically at 20 sites from October 2009 through September 2010. Bed-sediment and biota samples were collected once at 13 sites during August 2010. This report presents the analytical results and quality-assurance data for water-quality, bed-sediment, and biota samples collected at sites from October 2009 through September 2010. Water-quality data include concentrations of selected major ions, trace elements, and suspended sediment. Turbidity was analyzed for water samples collected at the four sites where seasonal daily values of turbidity were being determined. Daily values of suspended-sediment concentration and suspended-sediment discharge were determined for four sites. Bed-sediment data include trace-element concentrations in the fine-grained fraction. Biological data include trace-element concentrations in whole-body tissue of aquatic benthic insects. Statistical summaries of water-quality, bed-sediment, and biological data for sites in the upper Clark Fork basin are provided for the period of record since 1985.

  15. Water-quality, bed-sediment, and biological data (October 2011 through September 2012) and statistical summaries of data for streams in the Clark Fork Basin, Montana

    Science.gov (United States)

    Dodge, Kent A.; Hornberger, Michelle I.; Dyke, Jessica

    2014-01-01

    Water, bed sediment, and biota were sampled in streams from Butte to near Missoula, Montana, as part of a monitoring program in the upper Clark Fork Basin of western Montana. The sampling program was conducted by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency to characterize aquatic resources in the Clark Fork Basin, with emphasis on trace elements associated with historic mining and smelting activities. Sampling sites were located on the Clark Fork and selected tributaries. Water samples were collected periodically at 20 sites from October 2011 through September 2012. Bed-sediment and biota samples were collected once at 13 sites during August 2012. This report presents the analytical results and quality-assurance data for water-quality, bed-sediment, and biota samples collected at sites from October 2011 through September 2012. Water-quality data include concentrations of selected major ions, trace elements, and suspended sediment. Turbidity was analyzed for water samples collected at the four sites where seasonal daily values of turbidity were being determined. Daily values of suspended-sediment concentration and suspended-sediment discharge were determined for four sites. Bed-sediment data include trace-element concentrations in the fine-grained fraction. Biological data include trace-element concentrations in whole-body tissue of aquatic benthic insects. Statistical summaries of water-quality, bed-sediment, and biological data for sites in the upper Clark Fork Basin are provided for the period of record since 1985.

  16. Habitat selection influences sex distribution, morphology, tissue biochemistry, and parasite load of juvenile coho salmon in the West Fork Smith River, Oregon

    Science.gov (United States)

    Given the strong influence of water temperature on salmonid physiology and behavior, in the summers of 2004 and 2005 we studied juvenile male and female coho salmon Oncorhynchus kisutch in two reaches of Oregon’s West Fork Smith River with different thermal profiles. Our goals we...

  17. Sampling and analysis plan for treatment water and creek water for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    This document provides the Environmental Restoration Program with information about the methodology, organizational structure, quality assurance and health and safety practices to be employed during the water sampling and analysis activities associated with the remediation of the Lower East Fork Poplar Creek Operable Unit during remediation of the National Oceanic and Atmospheric Administration and Bruner sites.

  18. Replication-Coupled Recruitment of Viral and Cellular Factors to Herpes Simplex Virus Type 1 Replication Forks for the Maintenance and Expression of Viral Genomes

    Science.gov (United States)

    Dembowski, Jill A.

    2017-01-01

    Herpes simplex virus type 1 (HSV-1) infects over half the human population. Much of the infectious cycle occurs in the nucleus of cells where the virus has evolved mechanisms to manipulate host processes for the production of virus. The genome of HSV-1 is coordinately expressed, maintained, and replicated such that progeny virions are produced within 4–6 hours post infection. In this study, we selectively purify HSV-1 replication forks and associated proteins from virus-infected cells and identify select viral and cellular replication, repair, and transcription factors that associate with viral replication forks. Pulse chase analyses and imaging studies reveal temporal and spatial dynamics between viral replication forks and associated proteins and demonstrate that several DNA repair complexes and key transcription factors are recruited to or near replication forks. Consistent with these observations we show that the initiation of viral DNA replication is sufficient to license late gene transcription. These data provide insight into mechanisms that couple HSV-1 DNA replication with transcription and repair for the coordinated expression and maintenance of the viral genome. PMID:28095497

  19. Sampling and analysis plan for treatment water and creek water for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-04-01

    This document provides the Environmental Restoration Program with information about the methodology, organizational structure, quality assurance and health and safety practices to be employed during the water sampling and analysis activities associated with the remediation of the Lower East Fork Poplar Creek Operable Unit during remediation of the National Oceanic and Atmospheric Administration and Bruner sites

  20. High-speed PIV applied to the wake of the NASA CRM model in ETW at high Re-number stall conditions for sub- and transonic speeds

    OpenAIRE

    Konrath, Robert; Geisler, Reinhard; Otter, Dirk; Philipp, Florian; Ehlers, Hauke; Agocs, Janos; Quest, Jürgen

    2015-01-01

    Within the framework of the EU project ESWIRP the Particle Image Velocimetry (PIV) using high-speed camera and laser has been used to measure the turbulent flow in the wake of a stalled aircraft wing. The measurements took place on the Common Research Model (CRM) provided by NASA in the pressurized cryogenic European Transonic Wind tunnel (ETW). A specific cryo-PIV system has been used and adapted for using high-speed PIV components under the cryogenic conditions of the wind tunnel faci...

  1. Orchestral Stalls, Honore Daumier

    Science.gov (United States)

    Lucero-Criswell, Amber

    2004-01-01

    Honore Daumier is probably best known as a politically motivated artist. Born in Marseilles in 1808, the French artist lived through one of the most turbulent eras of his country's history. With his artistic prowess and biting wit, he recorded the 1848 revolution, the rise and fall of the Second Empire, the Crimean and Franco-Prussian Wars, and…

  2. Historical perspectives on channel pattern in the Clark Fork River, Montana and implications for post-dam removal restoration

    Science.gov (United States)

    Woelfle-Erskine, C. A.; Wilcox, A. C.

    2009-12-01

    Active restoration approaches such as channel reconstruction have moved beyond the realm of small streams and are being applied to larger rivers. Uncertainties arising from limited knowledge, fluvial and ecosystem variability, and contaminants are especially significant in restoration of large rivers, where project costs and the social, infrastructural, and ecological costs of failure are high. We use the case of Milltown Dam removal on the Clark Fork River, Montana and subsequent channel reconstruction in the former reservoir to examine the use of historical research and uncertainty analysis in river restoration. At a cost of approximately $120 million, the Milltown Dam removal involves the mechanical removal of approximately 2 million cubic meters of sediments contaminated by upstream mining, followed by restoration of the former reservoir reach in which a single-thread meandering channel is being constructed. Historical maps, surveys, photographs, and accounts suggest a conceptual model of a multi-thread, anastomosing river in the reach targeted for channel reconstruction, upstream of the confluence of the Clark Fork and Blackfoot Rivers. We supplemented historical research with analysis of aerial photographs, topographic data, and USGS stage-discharge measurements in a lotic but reservoir-influenced reach of the Clark Fork River within our study area to estimate avulsion frequency (0.8 avulsions/year over a 70-year period) and average rates of lateral migration and aggradation. These were used to calculate the mobility number, a dimensionless relationship between channel filling and lateral migration timescales that can be used to predict whether a river’s planform is single or multi-threaded. The mobility number within our study reach ranged from 0.6 (multi-thread channel) to 1.7 (transitional channel). We predict that, in the absence of active channel reconstruction, the post-dam channel pattern would evolve to one that alternates between single and multi

  3. The tuning fork test—a useful tool for improving specificity in “Ottawa positive” patients after ankle inversion injury

    Science.gov (United States)

    Dissmann, P D; Han, K H

    2006-01-01

    The Ottawa ankle rules are a clinical instrument calibrated towards a high sensitivity in order not to miss any fractures of the ankle or mid‐foot. This is at the cost of a mean specificity of around only 32%. The aim of this study was to determine the suitability of tuning fork testing in combination with existing Ottawa guidance for increasing the specificity in detecting fractures of the lateral malleolus. A prospective pilot study was carried out, in which a single trained investigator examined all patients with already “Ottawa positive” findings for possible lateral malleolus injury by applying a tuning fork (C° 128 Hz). The tuning fork test findings were compared with formal reports of plain ankle radiographs using simple cross‐table analysis. The observed prevalence of ankle fractures was 5 of 49 (10%). Sensitivity and specificity were calculated as 100% and 61%, respectively, for tuning fork testing on the tip of the lateral malleolus (TLM), and as 100% and 95%, respectively, for testing on the distal fibula shaft (DFS). The associated positive and negative likelihood ratios were 2.59 and 0 (TLM), and 22 and 0 (DFS), respectively. The data were significant, with p = 0.014 (TLM) and p<0.001 (DFS). This study suggests that additional tuning fork testing of “Ottawa positive” patients may lead to a marked reduction in ankle radiographs, with consequently reduced radiation exposure and journey time. This may be particularly relevant in situations where radiological facilities are not readily available (expedition medicine) or where access to these has to be prioritised (major incidents, natural catastrophes). PMID:16988308

  4. Recent Approaches to Modeling Transport of Mercury in Surface Water and Groundwater - Case Study in Upper East Fork Poplar Creek, Oak Ridge, TN - 13349

    International Nuclear Information System (INIS)

    Bostick, Kent; Daniel, Anamary; Tachiev, Georgio; Malek-Mohammadi, Siamak

    2013-01-01

    In this case study, groundwater/surface water modeling was used to determine efficacy of stabilization in place with hydrologic isolation for remediation of mercury contaminated areas in the Upper East Fork Poplar Creek (UEFPC) Watershed in Oak Ridge, TN. The modeling simulates the potential for mercury in soil to contaminate groundwater above industrial use risk standards and to contribute to surface water contamination. The modeling approach is unique in that it couples watershed hydrology with the total mercury transport and provides a tool for analysis of changes in mercury load related to daily precipitation, evaporation, and runoff from storms. The model also allows for simulation of colloidal transport of total mercury in surface water. Previous models for the watershed only simulated average yearly conditions and dissolved concentrations that are not sufficient for predicting mercury flux under variable flow conditions that control colloidal transport of mercury in the watershed. The transport of mercury from groundwater to surface water from mercury sources identified from information in the Oak Ridge Environmental Information System was simulated using a watershed scale model calibrated to match observed daily creek flow, total suspended solids and mercury fluxes. Mercury sources at the former Building 81-10 area, where mercury was previously retorted, were modeled using a telescopic refined mesh with boundary conditions extracted from the watershed model. Modeling on a watershed scale indicated that only source excavation for soils/sediment in the vicinity of UEFPC had any effect on mercury flux in surface water. The simulations showed that colloidal transport contributed 85 percent of the total mercury flux leaving the UEFPC watershed under high flow conditions. Simulation of dissolved mercury transport from liquid elemental mercury and adsorbed sources in soil at former Building 81-10 indicated that dissolved concentrations are orders of magnitude

  5. Differences in defensive volatiles of the forked fungus beetle, Bolitotherus cornutus, living on two species of fungus.

    Science.gov (United States)

    Holliday, Alison E; Walker, Faye M; Brodie, Edmund D; Formica, Vincent A

    2009-11-01

    Forked fungus beetles, Bolitotherus cornutus, feed, mate, and live on the brackets of several species of shelf fungus that grow on decaying logs. In response to the specific threat stimulus of mammalian breath, B. cornutus beetles produce a volatile defensive secretion. We tested beetles collected from different host fungi to determine whether defensive secretion blends varied with host type. Using solid phase microextraction and gas chromatography-mass spectrometry, we detected large amounts of the alkylated benzoquinones, methyl-p-benzoquinone (toluquinone) and ethyl-p-benzoquinone, and smaller quantities of p-benzoquinone, 3-methylphenol (m-cresol), 3-ethylphenol, 2-methylhydroquinone, and 2-ethylhydroquinone in secretions. Volatile composition did not differ between male and female beetles. Secretions did differ between beetles collected from two species of fungus, Ganoderma applanatum and Fomes fomentarius, with the relative amount of p-benzoquinone secreted being the most important factor. Other relationships among the volatile components are discussed.

  6. Postwildfire debris-flow hazard assessment of the area burned by the 2013 West Fork Fire Complex, southwestern Colorado

    Science.gov (United States)

    Verdin, Kristine L.; Dupree, Jean A.; Stevens, Michael R.

    2013-01-01

    This report presents a preliminary emergency assessment of the debris-flow hazards from drainage basins burned by the 2013 West Fork Fire Complex near South Fork in southwestern Colorado. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence, potential volume of debris flows, and the combined debris-flow hazard ranking along the drainage network within and just downstream from the burned area, and to estimate the same for 54 drainage basins of interest within the perimeter of the burned area. Input data for the debris-flow models included topographic variables, soil characteristics, burn severity, and rainfall totals and intensities for a (1) 2-year-recurrence, 1-hour-duration rainfall, referred to as a 2-year storm; (2) 10-year-recurrence, 1-hour-duration rainfall, referred to as a 10-year storm; and (3) 25-year-recurrence, 1-hour-duration rainfall, referred to as a 25-year storm. Estimated debris-flow probabilities at the pour points of the 54 drainage basins of interest ranged from less than 1 to 65 percent in response to the 2-year storm; from 1 to 77 percent in response to the 10-year storm; and from 1 to 83 percent in response to the 25-year storm. Twelve of the 54 drainage basins of interest have a 30-percent probability or greater of producing a debris flow in response to the 25-year storm. Estimated debris-flow volumes for all rainfalls modeled range from a low of 2,400 cubic meters to a high of greater than 100,000 cubic meters. Estimated debris-flow volumes increase with basin size and distance along the drainage network, but some smaller drainages also were predicted to produce substantial debris flows. One of the 54 drainage basins of interest had the highest combined hazard ranking, while 9 other basins had the second highest combined hazard ranking. Of these 10 basins with the 2 highest

  7. Final report from VFL technologies for the pilot-scale thermal treatment of Lower East Fork Poplar Creek floodplain soils

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-09-01

    The Lower East Fork Poplar Creek (LEFPC) extends fourteen (14) miles through Oak Ridge, TN. The Creek sediments and surrounding floodplain soils are contaminated with mercury compounds. This project involved a comprehensive pilot demonstration on thermal desorption of these soils to validate the feasibility of the remedial technology which had been identified in previous studies. Thermal desorption is a technology that utilizes heating or drying of soils to induce volatilization of contaminants. These contaminants are then vaporized and either incinerated or condensed in the second stage of desorption. Mercury (Hg), which was the principal contaminate of concern, was collected by condensers in a vapor collection system. This type of system insured that the toxic mercury vapors did not escape to the atmosphere.

  8. Determination of the static spring constant of electrically-driven quartz tuning forks with two freely oscillating prongs

    International Nuclear Information System (INIS)

    González, Laura; Oria, Roger; Botaya, Luis; Puig-Vidal, Manel; Otero, Jorge

    2015-01-01

    Quartz tuning forks have become popular in nanotechnology applications, especially as sensors for scanning probe microscopy. The sensor’s spring constant and the oscillation amplitude are required parameters to evaluate the tip-sample forces; however, there is certain controversy within the research community as to how to arrive at a value for the static spring constant of the device when working in shear mode. Here, we present two different methods based on finite element simulations, to determine the value of the spring constant of the sensors: the amplitude and Cleveland methods. The results obtained using these methods are compared to those using the geometrical method, and show that the latter overestimates the spring constant of the device. (paper)

  9. ATR-Chk1-APC/C-dependent stabilization of Cdc7-ASK (Dbf4) kinase is required for DNA lesion bypass under replication stress

    DEFF Research Database (Denmark)

    Yamada, M.; Watanabe, K.; Mistrik, M.

    2013-01-01

    replication. Stalled DNA replication evoked stabilization of the Cdc7-ASK (Dbf4) complex in a manner dependent on ATR-Chk1-mediated checkpoint signaling and its interplay with the anaphase-promoting complex/cyclosomeCdh1 (APC/C) ubiquitin ligase. Mechanistically, Chk1 kinase inactivates APC/C through...... degradation of Cdh1 upon replication block, thereby stabilizing APC/C substrates, including Cdc7-ASK (Dbf4). Furthermore, motif C of ASK (Dbf4) interacts with the N-terminal region of RAD18 ubiquitin ligase, and this interaction is required for chromatin binding of RAD18. Impaired interaction of ASK (Dbf4...

  10. The Effect of Different Types of Physical Exercise on the Behavioural and Physiological Parameters of Standardbred Horses Housed in Single Stalls

    Directory of Open Access Journals (Sweden)

    Barbara Padalino

    2014-01-01

    Full Text Available The aim of this study was to investigate the impacts of three different physical exercises on the physiological and behavioural patterns of Standardbred trotters housed in single stalls. Twelve racing mares were observed twice during each different exercise: daily training (DT consisted of forty minutes at slow trot (4-5 m/s in a small track; maximal exercise (ME consisted of 1600 m run at maximal velocity; race (R was a real race of 1600 m. The mares were examined at rest in their stall (Time I, soon after the completion of the exercise (Time II, one hour (Time III, and two hours (Time IV after the exercise. Their heart rate, respiratory rate, and rectal temperature were recorded and they were videotaped in order to complete a focal animal sampling ethogram. All physiological parameters increased after exercise, in accordance with its intensity. After R and ME horses spent more time drinking, eating, and standing. The incidence of abnormal behaviours was very low and it was not affected by the different types of exercise. Overall, the assessment of horse behaviour after physical exercise by means of a focal animal sampling ethogram represents a useful tool to monitor equine welfare.

  11. Avaliação de diferentes materiais para recobrimento de camas em baias de galpão modelo free-stall

    Directory of Open Access Journals (Sweden)

    Daiane Cecchin

    2014-01-01

    Full Text Available Objetivou-se, com o presente trabalho, comparar o uso de cama de colchão de borracha e de areia no recobrimento da superfície de baias para confinamento tipo free-stall. Foram monitoradas 18 vacas holandesas confinadas em galpão modelo free-stall cujas baias foram recobertas com camas de areia e colchão de borracha (tratamentos. O delineamento experimental foi em blocos casualizados. Os parâmetros comportamentais estudados foram os tempos despendidos nas atividades: deitada em ócio e deitada ruminando, em pé em ócio sobre a cama, em pé ruminando sobre a cama, registrados a cada 10 min. As variáveis ambientais e temperatura da superfície das camas foram registradas a cada hora. Houve maior preferência dos animais pela cama de areia para os comportamentos deitada em ócio e deitada ruminando. As vacas permaneceram mais tempo deitadas em cama de borracha somente nos períodos mais frescos (noite e madrugada, devido à temperatura da cama. A temperatura da borracha foi maior que areia nos horários mais quentes do dia (notadamente durante o período da tarde, enquanto à noite se apresentou mais fria.

  12. Linking habitat quality with trophic performance of steelhead along forest gradients in the South Fork Trinity River Watershed, California

    Science.gov (United States)

    McCarthy, Sarah G.; Duda, Jeffrey J.; Emlen, John M.; Hodgson, Garth R.; Beauchamp, David A.

    2009-01-01

    We examined invertebrate prey, fish diet, and energy assimilation in relation to habitat variation for steelhead Oncorhynchus mykiss (anadromous rainbow trout) and rainbow trout in nine low-order tributaries of the South Fork Trinity River, northern California. These streams spanned a range of environmental conditions, which allowed us to use bioenergetics modeling to determine the relative effects of forest cover, stream temperature, season, and fish age on food consumption and growth efficiency. Evidence of seasonal shifts in reliance on aquatic versus terrestrial food sources was detected among forest cover categories and fish ages, although these categories were not robust indicators of O. mykiss condition and growth efficiency. Consumption estimates were generally less than 20% of maximum consumption, and fish lost weight in some streams during summer low-flow conditions when stream temperatures exceeded 15°C. Current 100-year climate change projections for California threaten to exacerbate negative growth patterns and may undermine the productivity of this steelhead population, which is currently not listed as endangered or threatened. To demonstrate the potential effect of global warming on fish growth, we ran three climate change scenarios in two representative streams. Simulated temperature increases ranging from 1.4°C to 5.5°C during the summer and from 1.5°C to 2.9C during the winter amplified the weight loss; estimated average growth for age-1 fish was 0.4–4.5 times lower than normal (low to high estimated temperature increase) in the warm stream and 0.05–0.8 times lower in the cool stream. We conclude that feeding rate and temperature during the summer currently limit the growth and productivity of steelhead and rainbow trout in low-order streams in the South Fork Trinity River basin and predict that climate change will have detrimental effects on steelhead growth as well as on macroinvertebrate communities and stream ecosystems in general.

  13. An evaluation of surgical outcome of bilateral cleft lip surgery using a modified Millard′s (Fork Flap technique

    Directory of Open Access Journals (Sweden)

    W L Adeyemo

    2013-01-01

    Full Text Available Background: The central third of the face is distorted by the bilateral cleft of the lip and palate and restoring the normal facial form is one of the primary goals for the reconstructive surgeons. The history of bilateral cleft lip repair has evolved from discarding the premaxilla and prolabium and approximating the lateral lip elements to a definitive lip and primary cleft nasal repair utilising the underlying musculature. The aim of this study was to review surgical outcome of bilateral cleft lip surgery (BCLS done at the Lagos University Teaching Hospital. Materials and Methods: A review of all cases of BCLS done between January 2007 and December 2012 at the Lagos University Teaching Hospital was done. Data analysis included age and sex of patients, type of cleft deformity and type of surgery (primary or secondary and whether the cleft deformity was syndromic and non-syndromic. Techniques of repair, surgical outcome and complications were also recorded. Results: A total of 39 cases of BCLS involving 21 males and 18 females were done during the period. This constituted 10% (39/390 of all cases of cleft surgery done during the period. There were 5 syndromic and 34 non-syndromic cases. Age of patients at time of surgery ranged between 3 months and 32 years. There were 24 bilateral cleft lip and palate deformities and 15 bilateral cleft lip deformities. Thirty-one of the cases were primary surgery, while 8 were secondary (revision surgery. The most common surgical technique employed was modified Fork flap (Millard technique, which was employed in 37 (95% cases. Conclusion: Bilateral cleft lip deformity is a common cleft deformity seen in clinical practice, surgical repair of which can be a challenge to an experienced surgeon. A modified Fork flap technique for repair of bilateral cleft lip is a reliable and versatile technique associated with excellent surgical outcome.

  14. Structure of eukaryotic CMG helicase at a replication fork and implications to replisome architecture and origin initiation.

    Science.gov (United States)

    Georgescu, Roxana; Yuan, Zuanning; Bai, Lin; de Luna Almeida Santos, Ruda; Sun, Jingchuan; Zhang, Dan; Yurieva, Olga; Li, Huilin; O'Donnell, Michael E

    2017-01-31

    The eukaryotic CMG (Cdc45, Mcm2-7, GINS) helicase consists of the Mcm2-7 hexameric ring along with five accessory factors. The Mcm2-7 heterohexamer, like other hexameric helicases, is shaped like a ring with two tiers, an N-tier ring composed of the N-terminal domains, and a C-tier of C-terminal domains; the C-tier contains the motor. In principle, either tier could translocate ahead of the other during movement on DNA. We have used cryo-EM single-particle 3D reconstruction to solve the structure of CMG in complex with a DNA fork. The duplex stem penetrates into the central channel of the N-tier and the unwound leading single-strand DNA traverses the channel through the N-tier into the C-tier motor, 5'-3' through CMG. Therefore, the N-tier ring is pushed ahead by the C-tier ring during CMG translocation, opposite the currently accepted polarity. The polarity of the N-tier ahead of the C-tier places the leading Pol ε below CMG and Pol α-primase at the top of CMG at the replication fork. Surprisingly, the new N-tier to C-tier polarity of translocation reveals an unforeseen quality-control mechanism at the origin. Thus, upon assembly of head-to-head CMGs that encircle double-stranded DNA at the origin, the two CMGs must pass one another to leave the origin and both must remodel onto opposite strands of single-stranded DNA to do so. We propose that head-to-head motors may generate energy that underlies initial melting at the origin.

  15. Phase II confirmatory sampling data report, Lower East Fork Poplar Creek, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1998-01-01

    A Remedial Investigation of East Fork Poplar Creek (EFPC) concluded that mercury is the principal contaminant of concern in the EFPC floodplain. The highest concentrations of mercury were found to be in a visually distinct black layer of soil that typically lies 15 to 30 cm (6 to 12 in.) below the surface. Mercury contamination was found to be situated in distinct areas along the floodplain, and generally at depths > 20 cm (8 in.) below the surface. In accordance with Comprehensive, Environmental Response, Compensation, and Liability Act (CERCLA), a feasibility study was prepared to assess alternatives for remediation, and a proposed plan was issued to the public in which a preferred alternative was identified. In response to public input, the plan was modified and US Department of Energy (DOE) issued a Record of Decision in 1995 committing to excavating all soil in the EFPC floodplain exceeding a concentration of 400 parts per million (ppm) of mercury. The Lower East Fork Poplar Creek (LEFPC) remedial action (RA) focuses on the stretch of EFPC flowing from Lake Reality at the Y-12 Plant, through the city of Oak Ridge, to Poplar Creek on the Oak Ridge Reservation (ORR) and its associated floodplain. Specific areas were identified that required remediation at the National Oceanographic and Atmospheric Administration (NOAA) Site along Illinois Avenue and at the Bruner Site along the Oak Ridge Turnpike. The RA was conducted in two separate phases. Phase 2, conducted from February to October 1997, completed the remediation efforts at the NOAA facility and fully remediated the Bruner Site. During both phases, data were collected to show that the remedial efforts performed at the NOAA and Bruner sites were successful in implementing the Record of Decision and had no adverse impact on the creek water quality or the city of Oak Ridge publicly owned treatment works

  16. Fork head transcription factor is required for ovarian mature in the brown planthopper, Nilaparvata lugens (Stål

    Directory of Open Access Journals (Sweden)

    Dong Xiaolin

    2011-12-01

    Full Text Available Abstract Background The brown planthopper (BPH, Nilaparvata lugens, is the most devastating rice pest in many areas throughout Asia. The reproductive system of female N. lugens consists of a pair of ovaries with 24-33 ovarioles per ovary in most individuals which determine its fecundity. The fork head (Fox is a transcriptional regulatory molecule, which regulates and controls many physiological processes in eukaryotes. The Fox family has several subclasses and members, and several Fox factors have been reported to be involved in regulating fecundity. Results We have cloned a fork head gene in N. lugens. The full-length cDNA of NlFoxA is 1789 bp and has an open reading frame of 1143 bp, encoding a protein of 380 amino acids. Quantitative real-time PCR (RT-qPCR and Reverse Transcription- PCR (RT-PCR analysis revealed that NlFoxA mRNA was mainly expressed in the fat body, midgut, cuticle and Malpighian tube, and was expressed continuously with little change during all the developmental stages. NlFoxA belongs to the FoxA subfamily of the Fox transcription factors. Knockdown of NlFoxA expression by RNAi using artificial diet containing double-stranded RNA (dsRNA significantly decreased the number of offspring and impacted the development of ovaries. ELISA and Western blot analyses showed that feeding-based RNAi of NlFoxA gene also resulted in decreased expression of vitellogenin (Vg protein. Conclusion NlFoxA plays an important role in regulation of fecundity and development of ovaries in the BPH via regulating vitellogenin expression.

  17. Flow field and oscillatory shear stress in a tuning-fork-shaped model of the average human carotid bifurcation.

    Science.gov (United States)

    Ding, Z; Wang, K; Li, J; Cong, X

    2001-12-01

    The oscillatory shear index (OSI) was developed based on the hypothesis that intimal hyperplasia was correlated with oscillatory shear stresses. However, the validity of the OSI was in question since the correlation between intimal thickness and the OSI at the side walls of the sinus in the Y-shaped model of the average human carotid bifurcation (Y-AHCB) was weak. The objectives of this paper are to examine whether the reason for the weak correlation lies in the deviation in geometry of Y-AHCB from real human carotid bifurcation, and whether this correlation is clearly improved in the tuning-fork-shaped model of the average human carotid bifurcation (TF-AHCB). The geometry of the TF-AHCB model was based on observation and statistical analysis of specimens from 74 cadavers. The flow fields in both models were studied and compared by using flow visualization methods under steady flow conditions and by using laser Doppler anemometer (LDA) under pulsatile flow conditions. The TF-shaped geometry leads to a more complex flow field than the Y-shaped geometry. This added complexity includes strengthened helical movements in the sinus, new flow separation zone, and directional changes in the secondary flow patterns. The results show that the OSI-values at the side walls of the sinus in the TF-shaped model were more than two times as large as those in the Y-shaped model. This study confirmed the stronger correlation between the OSI and intimal thickness in the tuning-fork geometry of human carotid bifurcation, and the TF-AHCB model is a significant improvement over the traditional Y-shaped model.

  18. Water-quality, bed-sediment, and biological data (October 2008 through September 2009) and statistical summaries of long-term data for streams in the Clark Fork basin, Montana

    Science.gov (United States)

    Dodge, Kent A.; Hornberger, Michelle I.; Dyke, Jessica

    2010-01-01

    Water, bed sediment, and biota were sampled in streams from Butte to near Missoula, Montana, as part of a long-term monitoring program in the upper Clark Fork basin; additional water samples were collected in the Clark Fork basin from sites near Missoula downstream to near the confluence of the Clark Fork and Flathead River as part of a supplemental sampling program. The sampling programs were conducted by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency to characterize aquatic resources in the Clark Fork basin of western Montana, with emphasis on trace elements associated with historic mining and smelting activities. Sampling sites were located on the Clark Fork and selected tributaries. Water samples were collected periodically at 24 sites from October 2008 through September 2009. Bed-sediment and biota samples were collected once at 13 sites during August 2009. This report presents the analytical results and quality-assurance data for water-quality, bed-sediment, and biota samples collected at all long-term and supplemental monitoring sites from October 2008 through September 2009. Water-quality data include concentrations of selected major ions, trace elements, and suspended sediment. Turbidity was analyzed for water samples collected at the four sites where seasonal daily values of turbidity were being determined as well as at Clark Fork above Missoula. Nutrients also were analyzed at all the supplemental water-quality sites, except for Clark Fork Bypass, near Bonner. Daily values of suspended-sediment concentration and suspended-sediment discharge were determined for four sites. Bed-sediment data include trace-element concentrations in the fine-grained fraction. Biological data include trace-element concentrations in whole-body tissue of aquatic benthic insects. Statistical summaries of long-term water-quality, bed-sediment, and biological data for sites in the upper Clark Fork basin are provided for the period of record

  19. Effect of timing of relocation of replacement gilts from group pens to individual stalls before breeding on fertility and well-being.

    Science.gov (United States)

    Knox, R V; Shen, J; Greiner, L L; Connor, J F

    2016-12-01

    Variation in gilt fertility is associated with increased replacement and reduced longevity. Stress before breeding is hypothesized to be involved in reduced fertility. This study tested the timing of gilt relocation from pens to individual stalls before breeding on fertility and well-being. The experiment was performed in replicates on a commercial research farm. After detection of first estrus, gilts ( = 563) were assigned to treatment for relocation into stalls 3 wk (REL3wk), 2 wk (REL2wk), or 1 wk (REL1wk) before breeding at second estrus. Subsets of gilts from each treatment ( = 60) were selected for assessment of follicles at second estrus. Data included interestrus interval, number of services, conception, farrowing, total born, and wean to service interval. Piglet birth weight was obtained on subsets of litters ( = 42/treatment). Measures of well-being included BW, backfat, BCS, lesions, and lameness from wk 1 after first estrus until wk 16. Gilt BW at wk 5 (158.4 kg) was not affected ( > 0.10) by treatment. Measures of BCS, lameness, and lesions at breeding and throughout gestation did not differ ( > 0.10). Treatment did not affect ( > 0.10) gilts expressing a normal interestrus interval of 18 to 24 d (83.4%) but did influence ( Gilts in REL3wk had a shorter ( Gilts with shorter intervals ( = 24) had fewer total born while gilts expressing longer cycles ( = 65) had reduced farrowing rates. The number of services (1.9) and number of follicles (19.7) at breeding were not affected ( > 0.10) by relocation. There was no effect of treatment on farrowing rate (85.2%), born alive (12.6), or any litter birth weight measures ( > 0.10). The percentage of sows bred within 7 d after weaning (94.4%) was also not affected by treatment ( > 0.10). These results suggest that the timing of relocation before breeding had no effect on well-being or on the majority of gilts with normal estrous cycles and their subsequent fertility. However, a smaller proportion of the gilts

  20. Characterization of beer flavour stability (EPR - spin trapping)

    International Nuclear Information System (INIS)

    Stasko, A.; Liptakova, M.; Malik, F.

    1999-01-01

    The beer flavour stability is coupled with free radical degradation processes. Probably, aldehydes produced during the brewery but also generated by stalling are responsible for beer flavour as well as for its breaking down. The storing beer at the lower temperatures and in the dark place inhibits, and otherwise the rising temperature and illumination accelerate the rate of such radical processes. Beers contain naturally occurring radical scavengers - antioxidants which inhibit such unwanted reactions. Then depleting of scavengers results in the breaking down of the beer stability. EPR spin trapping technique was used as monitor such processes and for characterising so the flavour stability of beer. The probe was temperated at 60 grad C in the cavity of EPR spectrometer in the presence of spin trapping agent, N-tert.-butyl-α-phenyl nitrone (PBN) and EPR spectra were recorded for few hours. After beer antioxidants become depleted, free radicals formed by the beer degradation are scavenged by PBN spin trap and this point is characterised with a dramatically increased concentration of the free radicals trapped

  1. Improving the lateral resolution of quartz tuning fork-based sensors in liquid by integrating commercial AFM tips into the fiber end.

    Science.gov (United States)

    Gonzalez, Laura; Martínez-Martín, David; Otero, Jorge; de Pablo, Pedro José; Puig-Vidal, Manel; Gómez-Herrero, Julio

    2015-01-14

    The use of quartz tuning fork sensors as probes for scanning probe microscopy is growing in popularity. Working in shear mode, some methods achieve a lateral resolution comparable with that obtained with standard cantilevered probes, but only in experiments conducted in air or vacuum. Here, we report a method to produce and use commercial AFM tips in electrically driven quartz tuning fork sensors operating in shear mode in a liquid environment. The process is based on attaching a standard AFM tip to the end of a fiber probe which has previously been sharpened. Only the end of the probe is immersed in the buffer solution during imaging. The lateral resolution achieved is about 6 times higher than that of the etched microfiber on its own.

  2. An experimental and numerical study of the atmospheric stability impact on wind turbine wakes

    DEFF Research Database (Denmark)

    Machefaux, Ewan; Larsen, Gunner Chr.; Koblitz, Tilman

    2016-01-01

    In this paper, the impact of atmospheric stability on a wind turbine wake is studied experimentally and numerically. The experimental approach is based on full-scale (nacelle based) pulsed lidar measurements of the wake flow field of a stall-regulated 500 kW turbine at the DTU Wind Energy, Risø...... campus test site. Wake measurements are averaged within a mean wind speed bin of 1 m s1 and classified according to atmospheric stability using three different metrics: the Obukhov length, the Bulk–Richardson number and the Froude number. Three test cases are subsequently defined covering various...... atmospheric conditions. Simulations are carried out using large eddy simulation and actuator disk rotor modeling. The turbulence properties of the incoming wind are adapted to the thermal stratification using a newly developed spectral tensor model that includes buoyancy effects. Discrepancies are discussed...

  3. Water-quality, bed-sediment, and biological data (October 2015 through September 2016) and statistical summaries of data for streams in the Clark Fork Basin, Montana

    Science.gov (United States)

    Dodge, Kent A.; Hornberger, Michelle I.; Turner, Matthew A.

    2018-03-30

    Water, bed sediment, and biota were sampled in selected streams from Butte to near Missoula, Montana, as part of a monitoring program in the upper Clark Fork Basin of western Montana. The sampling program was led by the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, to characterize aquatic resources in the Clark Fork Basin, with emphasis on trace elements associated with historic mining and smelting activities. Sampling sites were on the Clark Fork and selected tributaries. Water samples were collected periodically at 20 sites from October 2015 through September 2016. Bed-sediment and biota samples were collected once at 13 sites during August 2016.This report presents the analytical results and quality-assurance data for water-quality, bed-sediment, and biota samples collected at sites from October 2015 through September 2016. Water-quality data include concentrations of selected major ions, trace elements, and suspended sediment. Samples for analysis of turbidity were collected at 13 sites, whereas samples for analysis of dissolved organic carbon were collected at 10 sites. In addition, samples for analysis of nitrogen (nitrate plus nitrite) were collected at two sites. Daily values of mean suspended-sediment concentration and suspended-sediment discharge were determined for three sites. Seasonal daily values of turbidity were determined for five sites. Bed-sediment data include trace-element concentrations in the fine-grained (less than 0.063 millimeter) fraction. Biological data include trace-element concentrations in whole-body tissue of aquatic benthic insects. Statistical summaries of water-quality, bed-sediment, and biological data for sites in the upper Clark Fork Basin are provided for the period of record.

  4. Mercury and selenium concentrations in biofilm, macroinvertebrates, and fish collected in the Yankee Fork of the Salmon River, Idaho, USA, and their potential effects on fish health

    Science.gov (United States)

    Rhea, Darren T.; Farag, Aïda M.; Harper, David D.; McConnell, Elizabeth; Brumbaugh, William G.

    2013-01-01

    The Yankee Fork is a large tributary of the Salmon River located in central Idaho, USA, with an extensive history of placer and dredge-mining activities. Concentrations of selenium (Se) and mercury (Hg) in various aquatic trophic levels were measured in the Yankee Fork during 2001 and 2002. Various measurements of fish health were also performed. Sites included four on the mainstem of the Yankee Fork and two off-channel sites in partially reclaimed dredge pools used as rearing habitat for cultured salmonid eggs and fry. Hg concentrations in whole mountain whitefish and shorthead sculpin ranged from 0.28 to 0.56 μg/g dry weight (dw), concentrations that are generally less than those reported to have significant impacts on fish. Biofilm and invertebrates ranged from 0.05 to 0.43 μg Hg/g dw. Se concentrations measured in biota samples from the Yankee Fork were greater than many representative samples collected in the Snake and Columbia watersheds and often exceeded literature-based toxic thresholds. Biofilm and invertebrates ranged from 0.58 to 4.66 μg Se/g dw. Whole fish ranged from 3.92 to 7.10 μg Se/g dw, and gonads ranged from 6.91 to 31.84 μg Se/g dw. Whole-body Se concentrations exceeded reported toxicological thresholds at three of four sites and concentrations in liver samples were mostly greater than concentrations shown to have negative impacts on fish health. Histological examinations performed during this study noted liver abnormalities, especially in shorthead sculpin, a bottom-dwelling species.

  5. An Assessment of health risk associated with mercury in soil and sediment from East Fork Poplar Creek, Oak Ridge, Tennessee. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Revis, N.; Holdsworth, G.; Bingham, G.; King, A.; Elmore, J.

    1989-04-01

    This report presents results from a study conducted to determine the toxicity of Mercury in soils sediments samples. Mice were fed via diet, soils and sediment, from various locations along the East Fork Poplar creek. Tissue distribution of pollutants was determined at various intervals. The tissue level relative to toxicity was used to determine the effect of a complex matrix on the gastrointestinal absorption and tissue distribution of the pollutants (other pollutants included cadmium and selenium).

  6. Final Environmental Assessment for the Beddown and Flight Operations of Unmanned Aircraft Systems at Grand Forks Air Force Base, North Dakota

    Science.gov (United States)

    2008-08-01

    goose (Branta canadensis), great blue heron (Ardea herodias), mallard (Anas platyrhynchos), blue-winged teal (Anas discors), redhead duck (Aythya...decline of 0.9 percent for the state of North Dakota overall (USBC 2008). Additional information regarding demographic characteristics of the population...impacts of the Proposed Action, demographic and economics characteristics at GFAFB, and the City and County of Grand Forks were analyzed, as presented

  7. Water-quality, bed-sediment, and biological data (October 2010 through September 2011) and statistical summaries of data for streams in the Clark Fork basin, Montana

    Science.gov (United States)

    Dodge, Kent A.; Hornberger, Michelle I.; Dyke, Jessica

    2013-01-01

    Water, bed sediment, and biota were sampled in streams from Butte to near Missoula, Montana, as part of a monitoring program in the upper Clark Fork basin of western Montana; additional water samples were collected from near Galen to near Missoula at select sites as part of a supplemental sampling program. The sampling program was conducted by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency to characterize aquatic resources in the Clark Fork basin, with emphasis on trace elements associated with historic mining and smelting activities. Sampling sites were located on the Clark Fork and selected tributaries. Water samples were collected periodically at 20 sites from October 2010 through September 2011. Bed-sediment and biota samples were collected once at 14 sites during August 2011. This report presents the analytical results and quality-assurance data for water-quality, bed-sediment, and biota samples collected at sites from October 2010 through September 2011. Water-quality data include concentrations of selected major ions, trace elements, and suspended sediment. Turbidity was analyzed for water samples collected at the four sites where seasonal daily values of turbidity were being determined. Daily values of suspended-sediment concentration and suspended-sediment discharge were determined for four sites. Bed-sediment data include trace-element concentrations in the fine-grained fraction. Biological data include trace-element concentrations in whole-body tissue of aquatic benthic insects. Statistical summaries of water-quality, bed-sediment, and biological data for sites in the upper Clark Fork basin are provided for the period of record since 1985.

  8. Assessing the potential for rainbow trout reproduction in tributaries of the Mountain Fork River below Broken Bow Dam, southeastern Oklahoma

    Science.gov (United States)

    James M. Long; Trevor A. Starks; Tyler Farling; Robert. Bastarache

    2016-01-01

    Stocked trout (Salmonidae) in reservoir tailwater systems in the Southern United States have been shown to use tributary streams for spawning and rearing. The lower Mountain Fork of the Little River below Broken Bow Dam is one of two year-round tailwater trout fisheries in Oklahoma, and the only one with evidence of reproduction by stocked rainbow trout (Oncorhynchus...

  9. The C-terminal domain of the bacterial SSB protein acts as a DNA maintenance hub at active chromosome replication forks.

    Directory of Open Access Journals (Sweden)

    Audrey Costes

    2010-12-01

    Full Text Available We have investigated in vivo the role of the carboxy-terminal domain of the Bacillus subtilis Single-Stranded DNA Binding protein (SSB(Cter as a recruitment platform at active chromosomal forks for many proteins of the genome maintenance machineries. We probed this SSB(Cter interactome using GFP fusions and by Tap-tag and biochemical analysis. It includes at least 12 proteins. The interactome was previously shown to include PriA, RecG, and RecQ and extended in this study by addition of DnaE, SbcC, RarA, RecJ, RecO, XseA, Ung, YpbB, and YrrC. Targeting of YpbB to active forks appears to depend on RecS, a RecQ paralogue, with which it forms a stable complex. Most of these SSB partners are conserved in bacteria, while others, such as the essential DNA polymerase DnaE, YrrC, and the YpbB/RecS complex, appear to be specific to B. subtilis. SSB(Cter deletion has a moderate impact on B. subtilis cell growth. However, it markedly affects the efficiency of repair of damaged genomic DNA and arrested replication forks. ssbΔCter mutant cells appear deficient in RecA loading on ssDNA, explaining their inefficiency in triggering the SOS response upon exposure to genotoxic agents. Together, our findings show that the bacterial SSB(Cter acts as a DNA maintenance hub at active chromosomal forks that secures their propagation along the genome.

  10. Final report from VFL Technologies for the pilot-scale thermal treatment of Lower East Fork Poplar Creek floodplain soils. LEFPC appendices. Volume 6. Appendix VI-X

    International Nuclear Information System (INIS)

    1994-09-01

    This final report from VFL Technologies for the pilot-scale thermal treatment of lower East Fork Poplar Creek floodplain soils dated September 1994 contains LEFPC Appendices, Volume 6, Appendix VI - X. These appendices cover the following areas: chain of custody, miscellaneous process calculations (residence time and orifice plate calculations), waste management (mercury and radiation confirmatory testing before and after final verification run), health and safety (training, respirator fit test and radiation work permits), and transportation (soil receipt documentation)

  11. Experimental studies of flow separation and stalling on two-dimensional airfoils at low speeds. Phase 2: Studies with Fowler flap extended

    Science.gov (United States)

    Seetharam, H. C.; Wentz, W. H., Jr.

    1975-01-01

    Results were given on experimental studies of flow separation and stalling on a two-dimensional GA(W)-1 17 percent thick airfoil with an extended Fowler flap. Experimental velocity profiles obtained from a five tube probe survey with optimum flap gap and overlap setting (flap at 40 deg) are shown at various stations above, below, and behind the airfoil/flap combination for various angles of attack. The typical zones of steady flow, intermittent turbulence, and large scale turbulence were obtained from a hot wire anemometer survey and are depicted graphically for an angle of attack of 12.5 deg. Local skin friction distributions were obtained and are given for various angles of attack. Computer plots of the boundary layer profiles are shown for the case of the flap at 40 deg. Static pressure contours are also given. A GA(W)-2 section model was fabricated with 30 percent Fowler flaps and with pressure tabs.

  12. The efforts of a multidisciplinary approach in the rehabilitation institute for deaf children: A psychosocial intervention aimed at breaking the pattern of stalled productivity

    Directory of Open Access Journals (Sweden)

    Langher Viviana

    2012-01-01

    Full Text Available The multidisciplinary approach for the treatment of hearing impaired children presented the work group with several tasks: the group had to integrate different competences and techniques, to share common treatment goals, to manage relational dynamics with the children and their parents, and to explore the families' expectancies. These efforts may create stressful conditions for the work group and, consequently, might negatively affect the quality of the intervention to be carried out. Our aim was to illustrate a psychosocial analysis performed in a religious Institute for hearing impaired children, intended to break the pattern of the Institute's stalled productivity, to avoid inefficient and fragmented treatments, to prevent unelaborated relational dynamics among the staff members and between the staff and the children's families. By means of the Content Analysis of semi-structured interviews administered to staff-members and families we have analyzed the quality of the teamwork, the relational arrangements towards the families and local services (25 interviews with 5 staff members; the family-Institute relationship and the family's representation and satisfaction of the Institute (7 interviews with 13 hearing impaired parents and non-hearing impaired parents. The institute activity seemed to be more characterized by the maintenance of the relationship with the families per se, rather than oriented to productive goals. The non hearing impaired parents seemed to be more satisfied than the hearing-impaired parents, possibly because the former are more prepared to receive the Institute's help. The stalled productivity can only be overcome by the elaboration of those relational/emotional dynamics which prevent staff members and children's parents from focusing on productive goals. The staffmembers' training should be improved in order to develop specific competences, to perform an integrated, multidisciplinary approach in treatments, to negotiate

  13. Confederated Tribes of the Umatilla Indian Reservation North Fork John Day River Basin Anadromous Fish Enhancement Project, Annual Report for FY 2001.

    Energy Technology Data Exchange (ETDEWEB)

    Macy, Tom L.; James, Gary A.

    2003-03-01

    The CTUIR North Fork John Day River Basin Anadromous Enhancement Project (NFJDAFEP) identified and prioritized stream reaches in The North Fork John day River basin for habitat improvements during the 2000 project period. Public outreach was emphasized during this first year of the project. During the past year we concentrated on satisfying landowner needs, providing cost share alternatives, providing joint projects and starting implementation. We presented multiple funding and enhancement options to landowners. We concentrated on natural recovery methods, riparian fencing and offstream livestock water developments. Under this BPA contract four riparian easements have been signed protecting almost 5 miles of tributary streams. There are nine offstream water developments associated with these easements. Some landowners chose to participate in other programs based on Tribal outreach efforts. Some landowners chose NRCS programs for enhancement and others chose OWEB as a funding source. The exact amount of stream protection due to other funding sources probably exceeds that by BPA, however most would not have entered any program without initial Tribal outreach. Cooperation between the NRCS/FSA/SWCDs and the Tribe to create joint projects and develop alternative funding scenarios for riparian enhancement was a major effort. The Tribe also worked with the North Fork John Day Watershed Council, USFS and ODFW to coordinate projects and support similar projects throughout the John Day Basin.

  14. A one-dimensional, steady-state, dissolved-oxygen model and waste-load assimilation study for East Fork White River, Bartholomew County, Indiana

    Science.gov (United States)

    Wilber, William G.; Peters, James G.; Crawford, Charles G.

    1979-01-01

    A digital model calibrated to conditions in East Fork White River, Bartholomew County, IN, was used to develop alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. The model indicates that benthic-oxygen demand and the headwater concentrations of carbonaceous biochemical-oxygen demand, nitrogenous biochemical-oxygen demand, and dissolved oxygen are the most significant factors affecting the dissolved-oxygen concentration of East Fork White River downstream from the Columbus wastewater-treatment facility. The effect of effluent from the facility on the water quality of East Fork White River was minimal. The model also indicates that, with a benthic-oxygen demand of approximately 0.65 gram per square meter per day, the stream has no additional waste-load assimilative capacity during summer low flows. Regardless of the quality of the Columbus wastewater effluent, the minimum 24-hour average dissolved-oxygen concentration of at least 5 milligrams per liter, the State 's water-quality standard for streams, would not be met. Ammonia toxicity is not a limiting water-quality criterion during summer and winter low flows. During winter low flows, the current carbonaceous biochemical-oxygen demand limits for the Columbus wastewater-treatment facility will not result in violations of the in-stream dissolved-oxygen standard. (USGS)

  15. INTEGRATED OUTCROP AND SUBSURFACE STUDIES OF THE INTERWELL ENVIRONMENT OF CARBONATE RESERVOIRS: CLEAR FORK (LEONARDIAN-AGE) RESERVOIRS, WEST TEXAS AND NEW MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    F. Jerry Lucia

    2002-01-31

    This is the final report of the project ''Integrated Outcrop and Subsurface Studies of the Interwell Environment of Carbonate Reservoirs: Clear Fork (Leonardian-Age) Reservoirs, West Texas and New Mexico'', Department of Energy contract no. DE-AC26-98BC15105 and is the third in a series of similar projects funded jointly by the U.S. Department of Energy and The University of Texas at Austin, Bureau of Economic Geology, Reservoir Characterization Research Laboratory for Carbonates. All three projects focus on the integration of outcrop and subsurface data for the purpose of developing improved methods for modeling petrophysical properties in the interwell environment. The first project, funded by contract no. DE-AC22-89BC14470, was a study of San Andres outcrops in the Algerita Escarpment, Guadalupe Mountains, Texas and New Mexico, and the Seminole San Andres reservoir, Permian Basin. This study established the basic concepts for constructing a reservoir model using sequence-stratigraphic principles and rock-fabric, petrophysical relationships. The second project, funded by contract no. DE-AC22-93BC14895, was a study of Grayburg outcrops in the Brokeoff Mountains, New Mexico, and the South Cowden Grayburg reservoir, Permian Basin. This study developed a sequence-stratigraphic succession for the Grayburg and improved methods for locating remaining hydrocarbons in carbonate ramp reservoirs. The current study is of the Clear Fork Group in Apache Canyon, Sierra Diablo Mountains, West Texas, and the South Wasson Clear Fork reservoir, Permian Basin. The focus was on scales of heterogeneity, imaging high- and low-permeability layers, and the impact of fractures on reservoir performance. In this study (1) the Clear Fork cycle stratigraphy is defined, (2) important scales of petrophysical variability are confirmed, (3) a unique rock-fabric, petrophysical relationship is defined, (4) a porosity method for correlating high-frequency cycles and defining rock

  16. The use of computed neutron coincidence counting with time interval analysis for the analysis of Fork-measurements on a fresh MOX-LWR fuel assembly under water

    International Nuclear Information System (INIS)

    Baeten, P.; Bruggeman, M.; Carchon, R.

    1998-06-01

    The objective of this study was to investigate the influence of different important parameters on measurement results for various fork-detectors. Computed Neutron Coincidence Counting (CNCC) with Time Interval Analysis (TIA) was used for this study. The performance of the electronics for the different fork-detectors was studied by investigating the deadtime perturbed zone of the Rossi-alpha distribution in TIA. The measurement revealed anomalies in the performance of the electronics of the IAEA BWR and LANL fork-detector. The IAEA PWR fork-detector functioned well and the deadtime parameter was calculated. The optimal setting for the pre delay was investigated and it was found that a pre delay of 10 micro seconds should be considered as an optimum between excluding from analysis data in the deadtime perturbed zone and keeping a high signal-to-noise ratio. For the shift register electronics used with the fork-detectors, a pre delay of only 4.5 micro seconds was used. The study of the pre delay and the deadtime showed that the calculated triples-rate is strongly dependent on these parameters. An accurate determination of the triple-rate in this type of measurements has proven to be quite difficult and requires proper operation of the electronics, a correct pre delay and an accurate deadtime correction formalism. By varying the boron concentration in water, the change of the decay time of the Rossi-alpha distribution was clearly observed. This change is due to the variation of the thermal multiplication. The variation of this decay time with the boron concentration proves that Boehnel's model for fast neutron multiplication is not valid under these measurement conditions and that a model for fast and thermal multiplication should be used in order to obtain unbiased measurement results. CNCC with TIA has proved to be a valuable tool in which parameter settings can be varied a posterori and the optimal setting can be determined for each measurement. Moreover, the

  17. Design and Vibration Sensitivity Analysis of a MEMS Tuning Fork Gyroscope with an Anchored Diamond Coupling Mechanism

    Science.gov (United States)

    Guan, Yanwei; Gao, Shiqiao; Liu, Haipeng; Jin, Lei; Niu, Shaohua

    2016-01-01

    In this paper, a new micromachined tuning fork gyroscope (TFG) with an anchored diamond coupling mechanism is proposed while the mode ordering and the vibration sensitivity are also investigated. The sense-mode of the proposed TFG was optimized through use of an anchored diamond coupling spring, which enables the in-phase mode frequency to be 108.3% higher than the anti-phase one. The frequencies of the in- and anti-phase modes in the sense direction are 9799.6 Hz and 4705.3 Hz, respectively. The analytical solutions illustrate that the stiffness difference ratio of the in- and anti-phase modes is inversely proportional to the output induced by the vibration from the sense direction. Additionally, FEM simulations demonstrate that the stiffness difference ratio of the anchored diamond coupling TFG is 16.08 times larger than the direct coupling one while the vibration output is reduced by 94.1%. Consequently, the proposed new anchored diamond coupling TFG can structurally increase the stiffness difference ratio to improve the mode ordering and considerably reduce the vibration sensitivity without sacrificing the scale factor. PMID:27049385

  18. Postremediation monitoring program baseline assessment report, Lower East Fork Poplar Creek, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Greeley, M.S. Jr.; Ashwood, T.L.; Kszos, L.A.; Peterson, M.J.; Rash, C.D.; Southworth, G.R. [Oak Ridge National Lab., TN (United States); Phipps, T.L. [CKY, Inc. (United States)

    1998-04-01

    Lower East Fork Poplar Creek (LEFPC) and its floodplain are contaminated with mercury (Hg) from ongoing and historical releases from the US Department of Energy (DOE) Oak Ridge Y-12 Plant. A remedial investigation and feasibility study of LEFPC resulted in the signing of a Record of Decision (ROD) in August 1995. In response to the ROD, soil contaminated with mercury above 400 mg/kg was removed from two sites in LEFPC and the floodplain during a recently completed remedial action (RA). The Postremediation Monitoring Program (PMP) outlined in the LEFPC Monitoring Plan was envisioned to occur in two phases: (1) a baseline assessment prior to remediation and (2) postremediation monitoring. The current report summarizes the results of the baseline assessment of soil, water, biota, and groundwater usage in LEFPC and its floodplain conducted in 1995 and 1996 by personnel of the Oak Ridge National Laboratory Biological Monitoring and Abatement Program (BMAP). This report also includes some 1997 data from contaminated sites that did not undergo remediation during the RA (i.e., sites where mercury is greater than 200 mg/kg but less than 400 mg/kg). The baseline assessment described in this document is distinct and separate from both the remedial investigation/feasibility study the confirmatory sampling conducted by SAIC during the RA. The purpose of the current assessment was to provide preremediation baseline data for the LEFPC PMP outlined in the LEFPC Monitoring Plan, using common approaches and techniques, as specified in that plan.

  19. Postremediation monitoring program baseline assessment report, Lower East Fork Poplar Creek, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Greeley, M.S. Jr.; Ashwood, T.L.; Kszos, L.A.; Peterson, M.J.; Rash, C.D.; Southworth, G.R.; Phipps, T.L.

    1998-04-01

    Lower East Fork Poplar Creek (LEFPC) and its floodplain are contaminated with mercury (Hg) from ongoing and historical releases from the US Department of Energy (DOE) Oak Ridge Y-12 Plant. A remedial investigation and feasibility study of LEFPC resulted in the signing of a Record of Decision (ROD) in August 1995. In response to the ROD, soil contaminated with mercury above 400 mg/kg was removed from two sites in LEFPC and the floodplain during a recently completed remedial action (RA). The Postremediation Monitoring Program (PMP) outlined in the LEFPC Monitoring Plan was envisioned to occur in two phases: (1) a baseline assessment prior to remediation and (2) postremediation monitoring. The current report summarizes the results of the baseline assessment of soil, water, biota, and groundwater usage in LEFPC and its floodplain conducted in 1995 and 1996 by personnel of the Oak Ridge National Laboratory Biological Monitoring and Abatement Program (BMAP). This report also includes some 1997 data from contaminated sites that did not undergo remediation during the RA (i.e., sites where mercury is greater than 200 mg/kg but less than 400 mg/kg). The baseline assessment described in this document is distinct and separate from both the remedial investigation/feasibility study the confirmatory sampling conducted by SAIC during the RA. The purpose of the current assessment was to provide preremediation baseline data for the LEFPC PMP outlined in the LEFPC Monitoring Plan, using common approaches and techniques, as specified in that plan

  20. Investigation of Hyporheic Microbial Biofilms as Indicators of Heavy Metal Toxicity in the Clark Fork Basin, Montana

    Science.gov (United States)

    Barnhart, E. P.; Hwang, C.; Bouskill, N.; Hornberger, M.; Fields, M. W.

    2015-12-01

    Water-saturated sediments that underlie a stream channel contain microbial biofilms that are often responsible for the majority of the metabolic activity in river and stream ecosystems. Metal contamination from mining effluent can modify the biofilm community structure, diversity, and activity. Developing a mechanistic understanding of the biofilm response to metal contamination could provide a useful bioindicator of metal toxicity due to the ease of standard biofilm sampling, environmental ubiquity of biofilms and the rapid response of biofilms to environmental perturbation and metal toxicity. Here we present data on the structure of the biofilm community (e.g., microbial population composition and diversity) and trace metal concentrations in water, bed sediment and biota (benthic insects) across 15 sites in the Clark Fork Basin. Sample sites were selected across a historically-monitored metal pollution gradient at shallow riffles with bed sediment predominantly composed of pebbles, cobbles, and sand. Bed-sediment samples (for biofilm analysis) were obtained from the top 20 centimeters of the hyporheic zone and sieved using sterile sieves to obtain homogeneous sediment samples with particle sizes ranging from 1.70 to 2.36 millimeters. Linear discriminant analysis and effect size statistical methods were used to integrate the metals concentration data (for water and benthic-insects samples) with the microbial community analysis to identify microbial biomarkers of metal toxicity. The development of rapid microbial biomarker tools could provide reproducible and quantitative insights into the effectiveness of remediation activities on metal toxicity and advances in the field of environmental biomonitoring.

  1. Mercury and other mining-related contaminants in ospreys along the Upper Clark Fork River, Montana, USA.

    Science.gov (United States)

    Langner, Heiko W; Greene, Erick; Domenech, Robert; Staats, Molly F

    2012-05-01

    We investigated links between mining-related contaminants in river sediment and their occurrence in nestling ospreys (Pandion haliaetus) in the Clark Fork River Basin, Montana, USA. Blood and feather samples from 111 osprey chicks were collected during 4 years from nests along river sections with greatly different sediment concentrations of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), zinc (Zn), and mercury (Hg). No significant differences between river sections were found among Zn (3,150 ± 160 μg L(-1)) and Cd (ospreys (mean 548 μg L(-1)) were observed downstream from a contaminated tributary (1-4 mg kg(-1) in sediment). In river sections with lower Hg concentrations in sediment, there was a negative correlation between blood Hg concentration and chick mass, presumably due to high deposition rates into growing feathers. This relationship was absent in sections of high Hg exposure. Osprey blood and feathers are suitable for monitoring Hg in aquatic ecosystems; however, responses of As, Cd, Cu, Pb, and Zn are more subtle.

  2. Procedure for calculating estimated ultimate recoveries of Bakken and Three Forks Formations horizontal wells in the Williston Basin

    Science.gov (United States)

    Cook, Troy A.

    2013-01-01

    Estimated ultimate recoveries (EURs) are a key component in determining productivity of wells in continuous-type oil and gas reservoirs. EURs form the foundation of a well-performance-based assessment methodology initially developed by the U.S. Geological Survey (USGS; Schmoker, 1999). This methodology was formally reviewed by the American Association of Petroleum Geologists Committee on Resource Evaluation (Curtis and others, 2001). The EUR estimation methodology described in this paper was used in the 2013 USGS assessment of continuous oil resources in the Bakken and Three Forks Formations and incorporates uncertainties that would not normally be included in a basic decline-curve calculation. These uncertainties relate to (1) the mean time before failure of the entire well-production system (excluding economics), (2) the uncertainty of when (and if) a stable hyperbolic-decline profile is revealed in the production data, (3) the particular formation involved, (4) relations between initial production rates and a stable hyperbolic-decline profile, and (5) the final behavior of the decline extrapolation as production becomes more dependent on matrix storage.

  3. The Escherichia coli Tus-Ter replication fork barrier causes site-specific DNA replication perturbation in yeast.

    Science.gov (United States)

    Larsen, Nicolai B; Sass, Ehud; Suski, Catherine; Mankouri, Hocine W; Hickson, Ian D

    2014-04-07

    Replication fork (RF) pausing occurs at both 'programmed' sites and non-physiological barriers (for example, DNA adducts). Programmed RF pausing is required for site-specific DNA replication termination in Escherichia coli, and this process requires the binding of the polar terminator protein, Tus, to specific DNA sequences called Ter. Here, we demonstrate that Tus-Ter modules also induce polar RF pausing when engineered into the Saccharomyces cerevisiae genome. This heterologous RF barrier is distinct from a number of previously characterized, protein-mediated, RF pause sites in yeast, as it is neither Tof1-dependent nor counteracted by the Rrm3 helicase. Although the yeast replisome can overcome RF pausing at Tus-Ter modules, this event triggers site-specific homologous recombination that requires the RecQ helicase, Sgs1, for its timely resolution. We propose that Tus-Ter can be utilized as a versatile, site-specific, heterologous DNA replication-perturbing system, with a variety of potential applications.

  4. Second report on the Oak Ridge Y-12 Plant Biological Monitoring and Abatement Program for East Fork Poplar Creek

    International Nuclear Information System (INIS)

    Hinzman, R.L.; Black, M.C.

    1993-06-01

    As stipulated in the National Pollutant Discharge Elimination System (NDPES) permit issued to the Oak Ridge Y-12 Plant on May 24, 1986, a Biological Monitoring and Abatement Program (BMAP) was developed for the receiving stream, East Fork Poplar Creek (EFPC). The objectives of BMAP are (1) to demonstrate that the current effluent limitations established for the Y-12 Plant protect the classified uses of EFPC (e.g., the growth and propagation of fish and aquatic life), as designated by the Tennessee Department of Environment and Conservation (TDEC) and (2) to document the ecological effects resulting from implementation of a Water Pollution Control Program that includes construction of several large wastewater treatment facilities. BMAP consists of four major tasks: (1) ambient toxicity testing; (2) bioaccumulation studies; (3) biological indicator studies; and (4) ecological surveys of stream communities, including periphyton (attached algae), benthic (bottom-dwelling) macroinvertebrates, and fish. This document, the second in a series of reports on the results of the Y-12 Plant BMAP, describes studies that were conducted between July 1986 and July 1988, although additional data collected outside this time period are included, as appropriate

  5. Seasonal Alterations in Park Visitation, Amenity Use, and Physical Activity — Grand Forks, North Dakota, 2012–2013

    Science.gov (United States)

    Johnson, LuAnn

    2014-01-01

    Introduction Park amenities promote visitation and physical activity during summer. Physical activity declines during winter. Identifying park amenities that promote visitation during winter would increase year-round activity. The purpose of this study was to determine how park visitation, amenity choice, and physical activity intensity change across seasons. Methods Physical activity intensity of children and adults was assessed at 16 parks in Grand Forks, North Dakota, during summer and fall of 2012, and winter and spring of 2013. Results Park visitation was highest in spring and lowest in winter. Amenity use varied by season. Parks with water splash pads were visited more during summer, and playgrounds and open spaces were visited more during spring. Ice rinks were visited most in winter. Physical activity intensity was lowest in summer and highest in winter for each age group. The activity intensity observed for all young age groups ranged from 2.7 to 2.9 metabolic equivalents in summer and greater than 3 metabolic equivalents in all other seasons. Adults’ mean activity intensity was greater than 3 metabolic equivalents in winter. Conclusion Information on park visitation, amenity use, and activity intensity across seasons is valuable; it can be used when designing or redesigning parks in order to promote year-round physical activity. Redesigning parks in cold climates to include ice rinks, sledding hills, cross-country skiing, and indoor areas for physical activity would increase winter visitation and allow the park to serve as a year-round resource for physical activity. PMID:25211503

  6. Seasonal alterations in park visitation, amenity use, and physical activity--Grand Forks, North Dakota, 2012-2013.

    Science.gov (United States)

    Roemmich, James N; Johnson, LuAnn

    2014-09-11

    Park amenities promote visitation and physical activity during summer. Physical activity declines during winter. Identifying park amenities that promote visitation during winter would increase year-round activity. The purpose of this study was to determine how park visitation, amenity choice, and physical activity intensity change across seasons. Physical activity intensity of children and adults was assessed at 16 parks in Grand Forks, North Dakota, during summer and fall of 2012, and winter and spring of 2013. Park visitation was highest in spring and lowest in winter. Amenity use varied by season. Parks with water splash pads were visited more during summer, and playgrounds and open spaces were visited more during spring. Ice rinks were visited most in winter. Physical activity intensity was lowest in summer and highest in winter for each age group. The activity intensity observed for all young age groups ranged from 2.7 to 2.9 metabolic equivalents in summer and greater than 3 metabolic equivalents in all other seasons. Adults' mean activity intensity was greater than 3 metabolic equivalents in winter. Information on park visitation, amenity use, and activity intensity across seasons is valuable; it can be used when designing or redesigning parks in order to promote year-round physical activity. Redesigning parks in cold climates to include ice rinks, sledding hills, cross-country skiing, and indoor areas for physical activity would increase winter visitation and allow the park to serve as a year-round resource for physical activity.

  7. Design criteria applied for the Lower Pressure Tunnel of the North Fork Stanislaus River Hydroelectric Project in California

    Science.gov (United States)

    Schleiss, A.

    1988-07-01

    The application of various criteria and certain new approaches to design is illustrated by the example of the Lower Collierville Pressure Tunnel of the North Fork Stanislaus River Hydropower Project in California. With a maximum internal water pressure of 72 bar, Lower Collierville Tunnel will be, when commissioned in 1989, the highest stressed pressure tunnel in the world not situated in granitic rocks. The geological conditions and the results of the geotechnical investigations are described briefly. For the steel-lined portion of the tunnel, the approach for determining the bearing capacity of the rock mass and the load sharing between steel and rock is discussed. The required length of steel liner was determined on the basis of rock mechanical (hydraulic jacking) and rock hydraulic (seepage losses and extension of saturated zone due to seepage) criteria. The use of a new theory allows the effects of mechanical-hydraulic interaction to be taken into account. Finally the methods of estimating the expected water losses and the sealing effect of the consolidation grouting are described.

  8. Final report for the pilot-scale thermal treatment of Lower East Fork Poplar Creek floodplain soils

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-09-01

    IT Corporation (IT) was contracted by Martin Marietta Energy Systems, Inc. (Energy Systems) to perform a pilot-scale demonstration of the effectiveness of thermal desorption as a remedial technology for removing mercury from the Lower East Fork Poplar Creek (LEFPC) floodplain soil. Previous laboratory studies by Energy Systems suggested that this technology could reduce mercury to very low levels. This pilot-scale demonstration study was initiated to verify on an engineering scale the performance of thermal desorption. This report includes the details of the demonstration study, including descriptions of experimental equipment and procedures, test conditions, sampling and analysis, quality assurance (QA), detailed test results, and an engineering assessment of a conceptual full-scale treatment facility. The specific project tasks addressed in this report were performed between October 1993 and June 1994. These tasks include soil receipt, preparation, and characterization; prepilot (bench-scale) desorption tests; front-end materials handling tests; pilot tests; back-end materials handling tests; residuals treatment; and engineering scale-up assessment.

  9. Second report on the Oak Ridge Y-12 Plant Biological Monitoring and Abatement Program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Hinzman, R.L. [ed.; Adams, S.M. [Oak Ridge National Lab., TN (United States); Black, M.C. [Oklahoma State Univ., Stillwater, OK (United States)] [and others

    1993-06-01

    As stipulated in the National Pollutant Discharge Elimination System (NDPES) permit issued to the Oak Ridge Y-12 Plant on May 24, 1986, a Biological Monitoring and Abatement Program (BMAP) was developed for the receiving stream, East Fork Poplar Creek (EFPC). The objectives of BMAP are (1) to demonstrate that the current effluent limitations established for the Y-12 Plant protect the classified uses of EFPC (e.g., the growth and propagation of fish and aquatic life), as designated by the Tennessee Department of Environment and Conservation (TDEC) and (2) to document the ecological effects resulting from implementation of a Water Pollution Control Program that includes construction of several large wastewater treatment facilities. BMAP consists of four major tasks: (1) ambient toxicity testing; (2) bioaccumulation studies; (3) biological indicator studies; and (4) ecological surveys of stream communities, including periphyton (attached algae), benthic (bottom-dwelling) macroinvertebrates, and fish. This document, the second in a series of reports on the results of the Y-12 Plant BMAP, describes studies that were conducted between July 1986 and July 1988, although additional data collected outside this time period are included, as appropriate.

  10. First report on the Oak Ridge Y-12 Plant Biological Monitoring and Abatement Program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J.M.; Adams, S.M.; Allison, L.J.; Boston, H.L.; Huston, M.A.; McCarthy, J.F.; Smith, J.G.; Southworth, G.R.; Stewart, A.J. (Oak Ridge National Lab., TN (United States)); Black, M.C. (Oklahoma State Univ., Stillwater, OK (United States)); Gatz, A.J. Jr. (Ohio Wesleyan Univ., Delaware, OH (United States)); Hinzman, R.L. (Oak Ridge Research Inst., TN (United States)); Jimenez, B.D. (Puerto Rico Univ.,

    1992-07-01

    As stipulated in the National Pollutant Discharge Elimination System (NPDES) permit issued to the Oak Ridge Y-12 Plant on May 24, 1985, a Biological Monitoring and Abatement Program (BMAP) was developed for the receiving stream, East Fork Poplar Creek (EFPC). The objectives of the BMAP are (1) to demonstrate that the current effluent limitations established for the Oak Ridge Y-12 Plant protect the uses of EFPC (e.g., the growth and propagation of fish and aquatic life), as designated by the Tennessee Department of Environment and Conservation (TDEC) [formerly the Tennessee Department of Health and Environment (TDHE)], and (2) to document the ecological effects resulting from implementation of a water pollution control program that includes construction of several large wastewater treatment facilities. The BMAP consists of four major tasks: (1) ambient toxicity testing, (2) bioaccumulation studies, (3) biological indicator studies, and (4) ecological surveys of stream communities, including periphyton (attached algae), benthic macroinvertebrates, and fish. This document, the first in a series of reports on the results of the Y-12 Plant BMAP, describes studies that were conducted from May 1985 through September 1986.

  11. Groundwater quality assessment for the Upper East Fork Poplar Creek Hydrogeologic Regime at the Y-12 Plant

    International Nuclear Information System (INIS)

    1992-02-01

    This report contains groundwater quality data obtained during the 1991 calendar year at several waste management facilities and petroleum fuel underground storage tank (UST) sites associated with the Y-12 Plant. These sites are within the Upper East Fork Poplar Creek Hydrogeologic Regime (UEFPCHR), which is one of three regimes defined for the purposes of groundwater and surface-water quality monitoring and remediation. This report was prepared for informational purposes. Included are the analytical data for groundwater samples collected from selected monitoring wells during 1991 and the results for quality assurance/quality control (QA/QC) samples associated with each groundwater sample. This report also contains summaries of selected data, including ion-charge balances for each groundwater sample, a summary of analytical results for nitrate (a principle contaminant in the UEFPCHR), results of volatile organic compounds (VOCs) analyses validated using the associated QA/QC sample data, a summary of trace metal concentrations which exceeded drinking-water standards, and a summary of radiochemical analyses and associated counting errors

  12. Organic compounds in Elm Fork Trinity River water used for public supply near Carrollton, Texas, 2002-05

    Science.gov (United States)

    Ging, Patricia B.; Delzer, Gregory C.; Hamilton, Pixie A.

    2009-01-01

    Organic compounds studied in this U.S. Geological Survey (USGS) assessment generally are man-made, including pesticides, solvents, gasoline hydrocarbons, personal-care and domestic-use products, refrigerants, and propellants. A total of 103 of 277 compounds were detected at least once among the 30 samples of source water for a community water system on the Elm Fork Trinity River near Carrollton, Texas, collected approximately monthly during 2002-05. The diversity of compounds detected indicates a variety of different sources and uses (including wastewater discharge, industrial, agricultural, domestic, and others) and different pathways (including overland runoff and groundwater discharge) to drinking-water supplies. Nine compounds were detected year-round in source-water samples, including chloroform, methyl tert-butyl ether (MTBE), and selected herbicide compounds commonly used in the Trinity River Basin and in other urban areas across the United States. About 90 percent of the 42 compounds detected most frequently in source water (in at least 20 percent of the samples) also were detected most frequently in finished water (after treatment but before distribution). Concentrations for all detected compounds in source and finished water generally were less than 0.1 microgram per liter and always less than human-health benchmarks, which are available for about one-half of the detected compounds.

  13. A measurement of the hysteresis loop in force-spectroscopy curves using a tuning-fork atomic force microscope

    Directory of Open Access Journals (Sweden)

    Manfred Lange

    2012-03-01

    Full Text Available Measurements of the frequency shift versus distance in noncontact atomic force microscopy (NC-AFM allow measurements of the force gradient between the oscillating tip and a surface (force-spectroscopy measurements. When nonconservative forces act between the tip apex and the surface the oscillation amplitude is damped. The dissipation is caused by bistabilities in the potential energy surface of the tip–sample system, and the process can be understood as a hysteresis of forces between approach and retraction of the tip. In this paper, we present the direct measurement of the whole hysteresis loop in force-spectroscopy curves at 77 K on the PTCDA/Ag/Si(111 √3 × √3 surface by means of a tuning-fork-based NC-AFM with an oscillation amplitude smaller than the distance range of the hysteresis loop. The hysteresis effect is caused by the making and breaking of a bond between PTCDA molecules on the surface and a PTCDA molecule at the tip. The corresponding energy loss was determined to be 0.57 eV by evaluation of the force–distance curves upon approach and retraction. Furthermore, a second dissipation process was identified through the damping of the oscillation while the molecule on the tip is in contact with the surface. This dissipation process occurs mainly during the retraction of the tip. It reaches a maximum value of about 0.22 eV/cycle.

  14. Wear Analysis of Die Inserts in the Hot Forging Process of a Forked Type Forging Using Reverse Scanning Techniques

    Directory of Open Access Journals (Sweden)

    Łukasz Dworzak

    2017-12-01

    Full Text Available This article presents a wear analysis of die inserts used in the hot forging process of a forked forging (yoke, an element applied in steering systems of passenger vehicles. Studies involved the application of an original reverse scanning method intended for rapid and reliable wear analysis of forging tools (with complicated shape affording easy assessment without the need to dismount tools from the forging unit. The developed method involves analysis of progressive wear of forging tools based on measurements (scanning of forgings periodically collected from the process and constitutes a useful tool for measurement and testing. As the authors’ earlier works have demonstrated, the proposed new approach to analysis of tool wear with the application of reverse 3D scanning has proven successful in multiple instances in the case of axially symmetrical objects. The presented results of studies indicate that it is possible to utilize the expanded method to analyze the lifetime of forging tools, including tools with complex geometry. Application of the reverse scanning method allows for continuous and practical monitoring of the condition of forging tools over the course of the forging process and should have a positive impact on improving production output and reducing production costs.

  15. A resonant sensor composed of quartz double ended tuning fork and silicon substrate for digital acceleration measurement

    Energy Technology Data Exchange (ETDEWEB)

    Li, Cun; Zhao, Yulong, E-mail: zhaoyulong@mail.xjtu.edu.cn; Cheng, Rongjun; Yu, Zhongliang; Liu, Yan [State Key Laboratory for Manufacturing System Engineering, Xi' an Jiaotong University, Xi' an, Shannxi 710049 (China)

    2014-03-15

    Presented in this paper is a micro-resonant acceleration sensor based on the frequency shift of quartz double ended tuning fork (DETF). The structure is silicon substrate having a proof mass supported by two parallel flexure hinges as doubly sustained cantilever, with a resonating DETF located between the hinges. The acceleration normal to the chip plane induces an axial stress in the DETF beam and, in turn, a proportional shift in the beam resonant frequency. Substrate is manufactured by single-crystal silicon for stable mechanical properties and batch-fabrication processes. Electrodes on the four surfaces of DETF beam excite anti-phase vibration model, to balance inner stress and torque and imply a high quality factor. The sensor is simply packaged and operates unsealed in atmosphere for measurements. The tested natural frequency is 36.9 kHz and the sensitivity is 21 Hz/g on a nominally ±100 g device, which is in good agreement with analytical calculation and finite element simulation. The output frequency drifting is less than 0.5 Hz (0.0014% of steady output) within 1 h. The nonlinearity is 0.0019%FS and hysteresis is 0.0026%FS. The testing results confirm the feasibility of combining quartz DETF and silicon substrate to achieve a micro-resonant sensor based on simple processing for digital acceleration measurements.

  16. Measurements on spent-fuel assemblies at Arkansas Nuclear One using the Fork system. Final report, January 1995

    International Nuclear Information System (INIS)

    Ewing, R.I.; Bronowski, D.R.; Bosler, G.E.; Siebelist, R.; Priore, J.; Hansford, C.H.; Sullivan, S.

    1997-03-01

    The Fork measurement system has been used to examine spent-fuel assemblies at the two reactors of Arkansas Nuclear One, operated by Entergy Operations, Inc. The Unit 1 reactor is a Babcock and Wilcox (B and W) design, and the Unit 2 reactor is a Combustion Engineering (CE) design. The neutron and gamma-ray emissions from individual spent-fuel assemblies were measured in the storage pools by raising each assembly pathway out of the storage rack and performing a measurement near the center of the assembly. The overall accuracy of the measurements after corrections is about 2%. Thirty-four assemblies were examined at Unit 1, and forty-one assemblies at Unit 2. The average deviation of the burnup measurements from the calibration was 3.0% at Unit 1 and 3.5% at Unit 2, indicating 2 to 3% random variation among the reactor records. There was no indication of clearly anomalous assemblies. Axial Scans of the variation in neutron and gamma ray emission were obtained by collecting data at several locations along the length of three assemblies at Unit 2. Two of these assemblies were nonstandard in that each contained a small neutron source. The sources were detected by the axial scans. The test program was a cooperative effort involving Sandia National Laboratories, Los Alamos National Laboratory, Entergy Operations, Inc., the Electric Power Research Institute, and the Office of Civilian Radioactive Waste Management of the US Department of Energy

  17. Design and Analysis of a New Tuning Fork Structure for Resonant Pressure Sensor

    Directory of Open Access Journals (Sweden)

    Xiaodong Sun

    2016-08-01

    Full Text Available This paper presents a micromachined resonant pressure sensor. The sensor is designed to optimize the sensitivity and reduce the cross-talk between the driving electrodes and sensing electrodes. The relationship between the sensitivity of the sensor and the main design parameters is analyzed both theoretically and numerically. The sensing and driving electrodes are optimized to get both high sensing capacitance and low cross-talk. This sensor is fabricated using a micromachining process based on a silicon-on-insulator (SOI wafer. An open-loop measurement system and a closed-loop self-oscillation system is employed to measure the characteristics of the sensor. The experiment result shows that the sensor has a pressure sensitivity of about 29 Hz/kPa, a nonlinearity of 0.02%FS, a hysteresis error of 0.05%FS, and a repeatability error of 0.01%FS. The temperature coefficient is less than 2 Hz/°C in the range of −40 to 80 °C and the short-term stability of the sensor is better than 0.005%FS.

  18. Stability and control of wind farms in power systems

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, C.

    2006-10-15

    The Ph.D. project 'Stability and Control of Wind Farms in Power Systems' deals with some selected problems related to wind power in power systems. With increasing wind power penetration, wind turbines substitute the power production of conventional power plants. Therefore, wind turbines also have to take over the power system stabilisation and control tasks, that were traditionally carried out by conventional power plants. Out of the many aspects related to this problem, this project focuses on transient fault ride-through and power system stabilisation. The selection of turbine types considered in this project is limited to active-stall turbines and variable speed, variable pitch turbines with gearboxes and full-scale converter-connected synchronous generators. As a basis for the project, a study into the state of the art is conducted at the beginning of the project. Grid connection requirements that were in force, or published as drafts, at the time, and scientific literature related to the topic, are studied. The project is based on simulations of wind turbines in a power system simulations tool. Some of the models used in this project were readily available prior to the project; the development of others is part of the project. The most extensive modelling work deals with the design of the electrical part of the variable speed turbine and its controls. To simulate realistic grid operation the wind turbine models are connected to an aggregated model of the Nordic power system. For that purpose the Nordic power system model, which was available prior to the project, is extended with a realistic feeder configuration. It is commonly demanded from modern wind turbines, that they must not disconnect in case of transient faults. Therefore, controllers are designed that enable the two turbine types to ride through transient faults. With these transient fault controllers the wind turbines can stay connected to the grid, such that their generation capacity is

  19. p53 Maintains Genomic Stability by Preventing Interference between Transcription and Replication

    Directory of Open Access Journals (Sweden)

    Constance Qiao Xin Yeo

    2016-04-01

    Full Text Available p53 tumor suppressor maintains genomic stability, typically acting through cell-cycle arrest, senescence, and apoptosis. We discovered a function of p53 in preventing conflicts between transcription and replication, independent of its canonical roles. p53 deficiency sensitizes cells to Topoisomerase (Topo II inhibitors, resulting in DNA damage arising spontaneously during replication. Topoisomerase IIα (TOP2A-DNA complexes preferentially accumulate in isogenic p53 mutant or knockout cells, reflecting an increased recruitment of TOP2A to regulate DNA topology. We propose that p53 acts to prevent DNA topological stress originating from transcription during the S phase and, therefore, promotes normal replication fork progression. Consequently, replication fork progression is impaired in the absence of p53, which is reversed by transcription inhibition. Pharmacologic inhibition of transcription also attenuates DNA damage and decreases Topo-II-DNA complexes, restoring cell viability in p53-deficient cells. Together, our results demonstrate a function of p53 that may underlie its role in tumor suppression.

  20. Evaluation of Calendar Year 1996 groundwater and surface water quality data for the Upper East Fork Poplar Creek Hydrogeologic Regime at the US Department of Energy Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    This report presents an evaluation of the groundwater monitoring data obtained in the Upper East Fork Poplar Creek Hydrogeologic Regime (East Fork Regime) during calendar year (CY) 1996. The East Fork Regime encompasses several confirmed and suspected sources of groundwater contamination within industrialized areas of the US Department of Energy (DOE) Y-12 Plant in Bear Creek Valley (BCV) southeast of Oak Ridge, Tennessee. The CY 1996 groundwater and surface water monitoring data are presented in Calendar Year 1996 Annual Groundwater Monitoring Report for the Upper East Fork Poplar Creek Hydrogeologic Regime at the US Department of Energy Y-12 Plant, Oak Ridge, Tennessee, along with the required data evaluations specified in the Resource Conservation and Recovery Act (RCRA) post-closure permit for the East Fork Regime. This report provides additional evaluation of the CY 1996 groundwater and surface water monitoring data with an emphasis on regime-wide groundwater contamination and long-term concentration trends for regulated and non-regulated monitoring parameters.