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1

Mechanism of length determination in bacteriophage lambda tails.  

PubMed

The mechanism of length determination in bacteriophage lambda tails is discussed as a model for regulation in protein assembly systems. The lambda tail is a long flexible tube ending in a conical part and a single tail fiber. Its length is exactly determined in the sense that the number of major tail protein (gpV) molecules, which comprise more than 80% of the mass of the tail, is exactly the same in all tails. Assembly of gpV is regulated by the initiator complex, which contains the tail fiber and the conical part, and by the terminator protein gpU. There are two key points in the assembly of gpV with respect to length determination. (1) Assembly of gpV on the initiator pauses at the correct tail length. Binding of gpU to the tail only fixes the pause firmly. (2) When the tail length is too short, binding of gpU to tails is inhibited. Deletions and a duplication (both in frame) in gene H, which codes for one of the proteins in the initiator, result in production of phage particles with altered tail length. Moreover, the tail length is roughly proportional to the length of the mutated versions of gene H. This shows that the tail length is measured by the length of gene H protein (gpH), which seems to be approximately as long as the tail tube, if extended like a thread, according to secondary structure prediction (alpha-helices connected by other structures). Various pieces of evidence show that about six molecules of gpH are attached to the remaining portion of the initiator by the C-terminal part and folded into a somewhat compact form, while they are elongated as they are enclosed in the tail tube during assembly of gpV. Unlike interaction between the length-measuring genome RNA and the coat protein of tobacco mosaic virus, the major tail protein gpV does not bind specifically to the ruler protein gpH. Rather, gpH determines the tail length by inhibiting the binding of gpU to short tails and by signalling the pause when the correct tail length is attained. PMID:2150582

Katsura, I

1990-01-01

2

DETERMINATION OF UNSATURATED FLOW CHARACTERISTICS IN MINE TAILINGS  

Microsoft Academic Search

The design details of a modified permeameter for determining the unsaturated flow characteristics of tailings are presented in this paper. The key modifications in comparison to a conventional permeameter include the provision of adjustable sensors that move along with the slurry tailings as it settles due to desaturation during the testing period. The Instantaneous Profile Method (IPM) is proposed to

Patrick Brisson; Vinod K. Garga; Sai K. Vanapalli

3

Experimental determination of the distribution of tail states of hydrogenated amorphous silicon: A transient photocurrent analysis  

SciTech Connect

Recent experimental developments have cast doubt on the validity of the common assumption that the distribution of tail states of hydrogenated amorphous silicon exhibits a single exponential functional form. The authors employ transient photocurrent decay measurements to determine this distribution of tail states. In their approach, however, they determine the distribution of tail states directly from the experimental data, without assuming, a priori, a specific functional form. It is found that these experimental results are consistent with other more recent experimental determinations of the distribution of tail states, suggesting the possibility of deviations from a single exponential distribution of tail states in hydrogenated amorphous silicon.

Webb, D.P.; Chan, F.Y.M.; Zou, X.C.; Chan, Y.C.; Lam, Y.W.; Lin, S.H.; O'Leary, S.K.; Lim, P.K.

1997-07-01

4

Microbial communities involved in methane production from hydrocarbons in oil sands tailings.  

PubMed

Microbial metabolism of residual hydrocarbons, primarily short-chain n-alkanes and certain monoaromatic hydrocarbons, in oil sands tailings ponds produces large volumes of CH(4) in situ. We characterized the microbial communities involved in methanogenic biodegradation of whole naphtha (a bitumen extraction solvent) and its short-chain n-alkane (C(6)-C(10)) and BTEX (benzene, toluene, ethylbenzene, and xylenes) components using primary enrichment cultures derived from oil sands tailings. Clone libraries of bacterial 16S rRNA genes amplified from these enrichments showed increased proportions of two orders of Bacteria: Clostridiales and Syntrophobacterales, with Desulfotomaculum and Syntrophus/Smithella as the closest named relatives, respectively. In parallel archaeal clone libraries, sequences affiliated with cultivated acetoclastic methanogens (Methanosaetaceae) were enriched in cultures amended with n-alkanes, whereas hydrogenotrophic methanogens (Methanomicrobiales) were enriched with BTEX. Naphtha-amended cultures harbored a blend of these two archaeal communities. The results imply syntrophic oxidation of hydrocarbons in oil sands tailings, with the activities of different carbon flow pathways to CH(4) being influenced by the primary hydrocarbon substrate. These results have implications for predicting greenhouse gas emissions from oil sands tailings repositories. PMID:22894132

Siddique, Tariq; Penner, Tara; Klassen, Jonathan; Nesbø, Camilla; Foght, Julia M

2012-08-23

5

Involvement of single-stranded tails in homologous recombination of DNA injected into Xenopus laevis oocyte nuclei.  

PubMed Central

Homologous recombination of DNA molecules injected into Xenopus laevis oocyte nuclei is extremely efficient when those molecules are linear and have overlapping homologous ends. It was previously shown that a 5'----3' exonuclease activity in oocytes attacks injected linear DNAs and leaves them with single-stranded 3' tails. We tested the hypothesis that such tailed molecules are early intermediates on the pathway to recombination products. Substrates with 3' tails were made in vitro and injected into oocytes, where they recombined rapidly and efficiently. In experiments with mixed substrates, molecules with 3' tails entered recombination intermediates and products more rapidly than did molecules with flush ends. Molecules endowed in vitro with 5' tails also recombined efficiently in oocytes, but their rate was not faster than for flush-ended substrates. In most cases, the 5' tails served as templates for resynthesis of the 3' strands, regenerating duplex ends which then entered the normal recombination pathway. In oocytes from one animal, some of the 5' tails were removed, and this was exacerbated when resynthesis was partially blocked. Analysis by two-dimensional gel electrophoresis of recombination intermediates from 5'-tailed substrates confirmed that they had acquired 3' tails as a result of the action of the 5'----3' exonuclease. These results demonstrate that homologous recombination in oocytes proceeds via a pathway that involves single-stranded 3' tails. Molecular models incorporating this feature are discussed. Images

Maryon, E; Carroll, D

1991-01-01

6

Determination of the reaction rate coefficient of sulphide mine tailings deposited under water.  

PubMed

The efficiency of a water cover to limit dissolved oxygen (DO) availability to underlying acid-generating mine tailings can be assessed by calculating the DO flux at the tailings-water interface. Fick's equations, which are generally used to calculate this flux, require knowing the effective DO diffusion coefficient (Dw) and the reaction (consumption) rate coefficient (Kr) of the tailings, or the DO concentration profile. Whereas Dw can be accurately estimated, few studies have measured the parameter Kr for submerged sulphide tailings. The objective of this study was to determine Kr for underwater sulphide tailings in a laboratory experiment. Samples of sulphide mine tailings (an approximately 6 cm layer) were placed in a cell under a water cover (approximately 2 cm) maintained at constant DO concentration. Two tailings were studied: TA1 with high sulphide content (83% pyrite) and TA2 with low sulphide content (2.8% pyrite). DO concentration was measured with a microelectrode at various depths above and below the tailings-water interface at 1 mm intervals. Results indicate that steady-state condition was rapidly attained. As expected, a diffusive boundary layer (DBL) was observed in all cases. An iterative back-calculation process using the numerical code POLLUTEv6 and taking the DBL into account provided the Kr values used to match calculated and experimental concentration profiles. Kr obtained for tailings TA1 and TA2 was about 80 d(-1) and 6.5 d(-1), respectively. For comparison purposes, Kr obtained from cell tests on tailings TA1 was lower than Kr calculated from the sulphate production rate obtained from shake-flask tests. Steady-state DO flux at the water-tailings interface was then calculated with POLLUTEv6 using tailings characteristics Dw and Kr. For the tested conditions, DO flux ranged from 608 to 758 mg O2/m(2)/d for tailings TA1 and from 177 to 221 mg O2/m(2)/d for tailings TA2. The impact of placing a protective layer of inert material over the tailings was also investigated for tailings TA1 (with high sulphide content). A protective layer of only 5 cm reduced the DO flux into the tailings at about 5 mg/m(2)/d, compared to 608 mg O2/m(2)/d without a protective layer, or an approximately 99% reduction in flux. PMID:23906653

Awoh, Akué Sylvette; Mbonimpa, Mamert; Bussière, Bruno

2013-07-29

7

Age and sex determination of juvenile band-tailed pigeons  

USGS Publications Warehouse

Captive band-tailed pigeons (Columbafasciata) were studied to document progression of molts and plumages from juvenal to adult age. Immature pigeons began the post-juvenal molt at 35 days which continued up to 340 days. The only 3 plumage characters useful for identification and estimation of age were presence of juvenal lesser, middle, and greater secondary coverts, juvenal secondaries, and juvenal primaries. While juvenal primaries were still present, hatching dates could be estimated up to 252 days (N = 84). Secondary feather presence and molt stage could be used to identify juvenile pigeons for more than 340 days (N = 24). Using coloration of the crown and breast feathers, 96 percent of the immature pigeons examined (106 of 110) at 80 days of age were classified accurately as to sex.

White, J.A.; Braun, C.E.

1978-01-01

8

Mass distribution of a probable tail-length-determining protein in bacteriophage T4  

SciTech Connect

Analysis of dark-field scanning transmission electron micrographs of unstained freeze-dried specimens established that the interior of the intact bacteriophage T4 tail tube contains extra density that is missing in tubes artificially emptied by treatment with 3 M guanidine hydrochloride. The mass of the tail tube is 3.1 x 10W daltons, and the central channel is 3.2 nm in diameter. Quantitative analysis of the density data is consistent with the presence of up to six strands of a protein molecule in the central channel that could serve as the template or ruler structure that determines the length of the bacteriophage tail and that could be injected into the cell with the phage DNA.

Duda, R.L.; Wall, J.S.; Hainfeld, J.F.; Sweet, R.M.; Eiserling, F.A.

1985-08-01

9

Mass distribution of a probable tail-length-determining protein in bacteriophage T4.  

PubMed Central

Analysis of dark-field scanning transmission electron micrographs of unstained freeze-dried specimens established that the interior of the intact bacteriophage T4 tail tube contains extra density that is missing in tubes artificially emptied by treatment with 3 M guanidine hydrochloride. The mass of the tail tube is 3.1 X 10(6) daltons, and the central channel is 3.2 nm in diameter. Quantitative analysis of the density data is consistent with the presence of up to six strands of a protein molecule in the central channel that could serve as the template or ruler structure that determines the length of the bacteriophage tail and that could be injected into the cell with the phage DNA. Images

Duda, R L; Wall, J S; Hainfeld, J F; Sweet, R M; Eiserling, F A

1985-01-01

10

Alpha-1D adrenoceptors are involved in reserpine-induced supersensitivity of rat tail artery  

PubMed Central

We examined reserpine-induced chemical denervation supersensitivity with special reference to alpha-1 adrenoceptor (AR) subtypes. Chronic treatment with reserpine for 2 weeks depleted noradrenaline in the tail artery and spleen of rats. Noradrenaline in the thoracic aorta was negligible before and after reserpine treatment. The treatment with reserpine produced supersensitivity in the contractile responses of the rat tail artery to phenylephrine, 5-HT and KCl, resulting in leftward shift of concentration–response curves (11.6-, 2.5- and 1.1-fold at EC50 value, respectively). These results suggest a predominant sensitization of the alpha-1 AR-mediated response by reserpine treatment. BMY 7378 at a concentration (30 nM) specific for blocking the alpha-1D AR subtype, but not KMD-3213 at a concentration (10 nM) selective for blocking the alpha-1A AR subtype, inhibited the supersensitivity of the phenylephrine-induced response in the reserpine-treated artery. On the other hand, the response to phenylephrine in reserpine-untreated artery was selectively inhibited by the same concentration of KMD-3213, but not by BMY 7378. Prazosin, a subtype-nonselective antagonist, blocked the responses to phenylephrine with the same potency, regardless of reserpine treatment. In the thoracic aorta and spleen, no supersensitivity was produced in the responses to phenylephrine by reserpine treatment. In a tissue segment-binding study using [3H]-prazosin, the total density and affinity of alpha-1 ARs in the rat tail artery were not changed by treatment with reserpine. However, alpha-1D AR with high affinity for BMY 7378 was significantly detected in reserpine-treated tail artery, in contrast to untreated artery. Decreases in alpha-1A AR with high affinity for KMD-3213 and alpha-1B AR with low affinities for KMD-3213 and BMY 7378 were also estimated in reserpine-treated tail artery. Alpha-1D AR mRNA in rat tail artery increased to three-folds by reserpine treatment, whereas the levels of alpha-1A and 1B mRNAs were not significantly changed. The present results suggest that chronic treatment with reserpine affects the expression of alpha-1 AR subtypes of rat tail artery and that the induction of alpha-1D ARs with high affinity for catecholamines is in part associated with reserpine-induced supersensitivity.

Taki, Naoyuki; Tanaka, Takashi; Zhang, Li; Suzuki, Fumiko; Israilova, Malika; Taniguchi, Takanobu; Hiraizumi-Hiraoka, Yasuko; Shinozuka, Kazumasa; Kunitomo, Masaru; Muramatsu, Ikunobu

2004-01-01

11

Conspicuous involvement of desmin tail mutations in diverse cardiac and skeletal myopathies.  

PubMed

Myofibrillar myopathy (MFM) encompasses a genetically heterogeneous group of human diseases caused by mutations in genes coding for structural proteins of muscle. Mutations in the intermediate filament (IF) protein desmin (DES), a major cytoskeletal component of myocytes, lead to severe forms of "desminopathy," which affects cardiac, skeletal, and smooth muscle. Most mutations described reside in the central alpha-helical rod domain of desmin. Here we report three novel mutations--c.1325C>T (p.T442I), c.1360C>T (p.R454W), and c.1379G>T (p.S460I)--located in desmin's non-alpha-helical carboxy-terminal "tail" domain. We have investigated the impact of these and four--c.1237G>A (p.E413K), c.1346A>C (p.K449T), c.1353C>G (p.I451M), and c.1405G>A (p.V469M)--previously described "tail" mutations on in vitro filament formation and on the generation of ordered cytoskeletal arrays in transfected myoblasts. Although all but two mutants (p.E413K, p.R454W) assembled into IFs in vitro and all except p.E413K were incorporated into IF arrays in transfected C2C12 cells, filament properties differed significantly from wild-type desmin as revealed by viscometric assembly assays. Most notably, when coassembled with wild-type desmin, these mutants revealed a severe disturbance of filament-formation competence and filament-filament interactions, indicating an inherent incompatibility of mutant and wild-type protein to form mixed filaments. The various clinical phenotypes observed may reflect altered interactions of desmin's tail domain with different components of the myoblast cytoskeleton leading to diminished biomechanical properties and/or altered metabolism of the individual myocyte. Our in vitro assembly regimen proved to be a very sensible tool to detect if a particular desmin mutation is able to cause filament abnormalities. PMID:17221859

Bär, Harald; Goudeau, Bertrand; Wälde, Sarah; Casteras-Simon, Monique; Mücke, Norbert; Shatunov, Alexey; Goldberg, Y Paul; Clarke, Charles; Holton, Janice L; Eymard, Bruno; Katus, Hugo A; Fardeau, Michel; Goldfarb, Lev; Vicart, Patrick; Herrmann, Harald

2007-04-01

12

C-terminal Tail of FGF19 Determines Its Specificity toward Klotho Co-receptors*  

PubMed Central

FGF19 subfamily proteins (FGF19, FGF21, and FGF23) are unique members of fibroblast growth factors (FGFs) that regulate energy, bile acid, glucose, lipid, phosphate, and vitamin D homeostasis in an endocrine fashion. Their activities require the presence of ? or ?Klotho, two related single-pass transmembrane proteins, as co-receptors in relevant target tissues. We previously showed that FGF19 can bind to both ? and ?Klotho, whereas FGF21 and FGF23 can bind only to either ?Klotho or ?Klotho, respectively in vitro. To determine the mechanism regulating the binding and specificity among FGF19 subfamily members to Klotho family proteins, chimeric proteins between FGF19 subfamily members or chimeric proteins between Klotho family members were constructed to probe the interaction between those two families. Our results showed that a chimera of FGF19 with the FGF21 C-terminal tail interacts only with ?Klotho and a chimera with the FGF23 C-terminal tail interacts only with ?Klotho. FGF signaling assays also reflected the change of specificity we observed for the chimeras. These results identified the C-terminal tail of FGF19 as a region necessary for its recognition of Klotho family proteins. In addition, chimeras between ? and ?Klotho were also generated to probe the regions in Klotho proteins that are important for signaling by this FGF subfamily. Both FGF23 and FGF21 require intact ? or ?Klotho for signaling, respectively, whereas FGF19 can signal through a Klotho chimera consisting of the N terminus of ?Klotho and the C terminus of ?Klotho. Our results provide the first glimpse of the regions that regulate the binding specificity between this unique family of FGFs and their co-receptors.

Wu, Xinle; Lemon, Bryan; Li, XiaoFan; Gupte, Jamila; Weiszmann, Jennifer; Stevens, Jennitte; Hawkins, Nessa; Shen, Wenyan; Lindberg, Richard; Chen, Jin-Long; Tian, Hui; Li, Yang

2008-01-01

13

C-terminal tail of FGF19 determines its specificity toward Klotho co-receptors.  

PubMed

FGF19 subfamily proteins (FGF19, FGF21, and FGF23) are unique members of fibroblast growth factors (FGFs) that regulate energy, bile acid, glucose, lipid, phosphate, and vitamin D homeostasis in an endocrine fashion. Their activities require the presence of alpha or betaKlotho, two related single-pass transmembrane proteins, as co-receptors in relevant target tissues. We previously showed that FGF19 can bind to both alpha and betaKlotho, whereas FGF21 and FGF23 can bind only to either betaKlotho or alphaKlotho, respectively in vitro. To determine the mechanism regulating the binding and specificity among FGF19 subfamily members to Klotho family proteins, chimeric proteins between FGF19 subfamily members or chimeric proteins between Klotho family members were constructed to probe the interaction between those two families. Our results showed that a chimera of FGF19 with the FGF21 C-terminal tail interacts only with betaKlotho and a chimera with the FGF23 C-terminal tail interacts only with alphaKlotho. FGF signaling assays also reflected the change of specificity we observed for the chimeras. These results identified the C-terminal tail of FGF19 as a region necessary for its recognition of Klotho family proteins. In addition, chimeras between alpha and betaKlotho were also generated to probe the regions in Klotho proteins that are important for signaling by this FGF subfamily. Both FGF23 and FGF21 require intact alpha or betaKlotho for signaling, respectively, whereas FGF19 can signal through a Klotho chimera consisting of the N terminus of alphaKlotho and the C terminus of betaKlotho. Our results provide the first glimpse of the regions that regulate the binding specificity between this unique family of FGFs and their co-receptors. PMID:18829467

Wu, Xinle; Lemon, Bryan; Li, XiaoFan; Gupte, Jamila; Weiszmann, Jennifer; Stevens, Jennitte; Hawkins, Nessa; Shen, Wenyan; Lindberg, Richard; Chen, Jin-Long; Tian, Hui; Li, Yang

2008-10-01

14

On determining a 1-tailed upper limit for future sample HorRat values.  

PubMed

Two formulas were developed for use in computing 1-tailed upper limits for future HorRat values obtained from the collaborative study of materials. One formula is applicable when a future sample HorRat value H [formula: see text] is computed based on a known concentration (e.g., C = spike level and RSD(R) is the sample relative reproducibility standard deviation) and the other formula is applicable when the true concentration (C) is unknown and a future sample HorRat value [formula: see text] is computed using the sample mean (e.g., y, the collaborative study overall mean for an analyte). A Monte Carlo simulation procedure was developed using the Statistical Analysis System (SAS) software to assess the accuracy of the 2 developed formulas. Based on the degree of closeness between the simulated and calculated limits, the formulas for computing upper limits for future sample HorRat values will prove to be useful to Study Directors in determining worst case scenarios concerning a method's reproducibility precision relative to that predicted using the "Horwitz equation". We also define the current empirical HorRat limits as 1-tailed 100p% upper limits to assess the statistical consequence, in a probability sense, of their application as an analytical methods screening tool. PMID:17233107

McClure, Foster D; Lee, Jung K

15

Determinants of lifetime fitness in a cooperative breeder, the long-tailed tit Aegithalos caudatus  

Microsoft Academic Search

Summary 1. Long-tailed tits ( Aegithalos caudatus ) are a cooperatively breeding species in which helpers often invest effort in the provisioning of young that are not their own. 2. We quantified the lifetime reproductive success (LRS) and the individual fitness, lambda, of 228 long-tailed tits using 8 years of field data. Calculation of lambda took account of the effect

ANDREW D. C. MACCOLL; BEN J. HATCHWELL

2004-01-01

16

Distribution of black-tailed jackrabbit habitat determined by GIS in southwestern Idaho  

USGS Publications Warehouse

We developed a multivariate description of black-tailed jackrabbit (Lepus californicus) habitat associations from Geographical Information Systems (GIS) signatures surrounding known jackrabbit locations in the Snake River Birds of Prey National Conservation Area (NCA), in southwestern Idaho. Habitat associations were determined for characteristics within a 1-km radius (approx home range size) of jackrabbits sighted on night spotlight surveys conducted from 1987 through 1995. Predictive habitat variables were number of shrub, agriculture, and hydrography cells, mean and standard deviation of shrub patch size, habitat richness, and a measure of spatial heterogeneity. In winter, jackrabbits used smaller and less variable sizes of shrub patches and areas of higher spatial heterogeneity when compared to summer observations (P 0.05), differed significantly between high and low population phase. We used the Mahalanobis distance statistic to rank all 50-m cells in a 440,000-ha region relative to the multivariate mean habitat vector. On verification surveys to test predicted models, we sighted jackrabbits in areas ranked close to the mean habitat vector. Areas burned by large-scale fires between 1980 and 1992 or in an area repeatedly burned by military training activities had greater Mahalanobis distances from the mean habitat vector than unburned areas and were less likely to contain habitats used by jackrabbits.

Knick, Steven T.; Dyer, D. L.

1997-01-01

17

Evaluation of the Factors Involved in Bioaccumulation of gamma-Emmitting Radionuclides in White-Tailed Deer (Odocoileus Virginanus). Final Report.  

National Technical Information Service (NTIS)

The objectives of the work were to: determine the amounts and kinds of fallout gamma emitting radionuclides in an important food and sport animal, the white-tailed deer (Odocoileus virginianus) in the southeastern U.S.A.; elucidate some of the food chain ...

J. H. Jenkins

1977-01-01

18

Bacteriophage T4 Self-Assembly: Localization of gp3 and Its Role in Determining Tail Length  

PubMed Central

Gene 3 of bacteriophage T4 participates at a late stage in the T4 tail assembly pathway, but the hypothetical protein product, gp3, has never been identified in extracts of infected cells or in any tail assembly intermediate. In order to overcome this difficulty, we expressed gp3 in a high-efficiency plasmid expression vector and subsequently purified it for further analysis. The N-terminal sequence of the purified protein showed that the initial methionine had been removed. Variant C-terminal amino acid sequences were resolved by determining the cysteine content of the protein. The molecular mass of 20.6 kDa for the pure protein was confirmed by Western blotting, using a specific anti-gp3 serum for which the purified protein was the immunogen. We also demonstrated, for the first time, the physical presence of gp3 in the mature T4 phage particle and localized it to the tail tube. By finding a nonleaky, nonpermissive host for a gene 3 mutant, we could clearly demonstrate a new phenotype: the slow, aberrant elongation of the tail tube in the absence of gp3.

Vianelli, A.; Wang, G. R.; Gingery, M.; Duda, R. L.; Eiserling, F. A.; Goldberg, E. B.

2000-01-01

19

Structures and Interaction Analyses of Integrin ?M?2 Cytoplasmic Tails*  

PubMed Central

Integrins are heterodimeric (? and ? subunits) signal transducer proteins involved in cell adhesions and migrations. The cytosolic tails of integrins are essential for transmitting bidirectional signaling and also implicated in maintaining the resting states of the receptors. In addition, cytosolic tails of integrins often undergo post-translation modifications like phosphorylation. However, the consequences of phosphorylation on the structures and interactions are not clear. The leukocyte-specific integrin ?M?2 is essential for myeloid cell adhesion, phagocytosis, and degranulation. In this work, we determined solution structures of the myristoylated cytosolic tail of ?M and a Ser phosphorylated variant in dodecylphosphocholine micelles by NMR spectroscopy. Furthermore, the interactions between non-phosphorylated and phosphorylated ?M tails with ?2 tail were investigated by NMR and fluorescence resonance energy transfer (FRET). The three-dimensional structures of the 24-residue cytosolic tail of ?M or phosphorylated ?M are characterized by an N-terminal amphipathic helix and a loop at the C terminus. The residues at the loop are involved in packing interactions with the hydrophobic face of the helix. 15N-1H heteronuclear single quantum coherence experiments identified residues of ?M and ?2 tails that may be involved in the formation of a tail-tail heterocomplex. We further examined interactions between myristoylated ?2 tail in dodecylphosphocholine micelles with dansylated ?M tail peptides by FRET. These studies revealed enhanced interactions between ?M or phosphorylated ?M tails with ?2 tail with Kd values ?5.2 ± 0.6 and ?4.4 ± 0.7 ?m, respectively. Docked structures of tail-tail complexes delineated that the ?M/?2 interface at the cytosolic region could be sustained by a network of polar interactions, ionic interactions, and/or hydrogen bonds.

Chua, Geok-Lin; Tang, Xiao-Yan; Amalraj, Monalisa; Tan, Suet-Mien; Bhattacharjya, Surajit

2011-01-01

20

Properties of the type B histone acetyltransferase Hat1: H4 tail interaction, site preference, and involvement in DNA repair.  

PubMed

The Hat1 histone acetyltransferase catalyzes the acetylation of H4 at lysines 5 and 12, the same sites that are acetylated in newly synthesized histone H4. By performing histone acetyltransferase (HAT) assays on various synthetic H4 N-terminal peptides, we have examined the interactions between Hat1 and the H4 tail domain. It was found that acetylation requires the presence of positively charged amino acids at positions 8 and 16 of H4, positions that are normally occupied by lysine; however, lysine per se is not essential and can be replaced by arginine. In contrast, replacing Lys-8 and -16 of H4 with glutamines reduces acetylation to background levels. Similarly, phosphorylation of Ser-1 of the H4 tail depresses acetylation by both yeast Hat1p and the human HAT-B complex. These results strongly support the model proposed by Ramakrishnan and colleagues for the interaction between Hat1 and the H4 tail (Dutnall, R. N., Tafrov, S. T., Sternglanz, R., and Ramakrishnan, V. (1998) Cell 94, 427-438) and may have implications for the genetic analysis of histone acetylation. It was also found that Lys-12 of H4 is preferentially acetylated by human HAT-B, in further agreement with the proposed model of H4 tail binding. Finally, we have demonstrated that deletion of the hat1 gene from the fission yeast Schizosaccharomyces pombe causes increased sensitivity to the DNA-damaging agent methyl methanesulfonate in the absence of any additional mutations. This is in contrast to results obtained with a Saccharomyces cerevisiae hat1Delta strain, which must also carry mutations of the acetylatable lysines of H3 for heightened methyl methanesulfonate sensitivity to be observed. Thus, although the role of Hat1 in DNA damage repair is evolutionarily conserved, the ability of H3 acetylation to compensate for Hat1 deletion appears to be more variable. PMID:17052979

Benson, Laura J; Phillips, Jane A; Gu, Yongli; Parthun, Mark R; Hoffman, Charles S; Annunziato, Anthony T

2006-10-19

21

Evaluation of the factors involved in bioaccumulation of gamma-emmitting radionuclides in white-tailed deer (Odocoileus virginanus). Final report  

Microsoft Academic Search

The objectives of the work were to: determine the amounts and kinds of fallout gamma emitting radionuclides in an important food and sport animal, the white-tailed deer (Odocoileus virginianus) in the southeastern U.S.A.; elucidate some of the food chain interrelationships around the year; and see if a relationship exists between bioaccumulation in deer, the soils, the deer foods available, the

1977-01-01

22

Determination of serum haptoglobin reference value in clinically healthy Iranian fat-tailed sheep  

Microsoft Academic Search

Summary Blood samples were collected from the jugular vein of 101 clinically healthy Iranian fat-tailed sheep according to their age (<1, 1-3, 3-5 and >5 years) and sex. Serum haptoglobin (Hp) was measured based upon the preservation of the peroxidase activity of haemoglobin, which is directly proportional to the amount of Hp. The reference value for serum Hp of apparently

S. Nazifi

23

Hydrophobic Tail Length, Degree of Fluorination and Headgroup Stereochemistry are Determinants of the Biocompatibility of (Fluorinated) Carbohydrate Surfactants  

PubMed Central

A series of hydrocarbon and fluorocarbon carbohydrate surfactants with different headgroups (i.e., gluco-, galacto- and maltopyranoside) and (fluorinated) alkyl tails (i.e., C7 and C14 to C19) was synthesized to investigate trends in their cytotoxicity and haemolytic activity, and how surfactant-lipid interactions of selected surfactants contribute to these two measures of biocompatibility. All surfactants displayed low cytotoxicity (EC50 = 25 to > 250 ?M) and low haemolytic activity (EC50 = 0.2 to > 3.3 mM), with headgroup structure, tail length and degree of fluorination being important structural determinants for both endpoints. The EC50 values of hydrocarbon and fluorocarbon glucopyranoside surfactants displayed a “cut-off” effect (i.e., a maximum with respect to the chain length). According to steady-state fluorescence anisotropy studies, short chain (C7) surfactants partitioned less readily into model membranes, which explains their low cytotoxicity and haemolytic activity. Interestingly, galactopyranosides were less toxic compared to glucopyranosides with the same hydrophobic tail. Although both surfactant types only differ in the stereochemistry of the 4-OH group, hexadecyl gluco- and galactopyranoside surfactants had similar apparent membrane partition coefficients, but differed in their overall effect on the phase behaviour of DPPC model membranes, as assessed using steady-state fluorescence anisotropy studies. These observations suggest that highly selective surfactant-lipid interactions may be responsible for the differential cytotoxicity and, possible, haemolytic activity of hydrocarbon and fluorocarbon carbohydrate surfactants intended for a variety of pharmaceutical and biomedical applications.

Li, Xueshu; Turanek, Jaroslav; Knotigova, Pavlina; Kudlackova, Hana; Masek, Josef; Parkin, Sean; Rankin, Stephen E; Knutson, Barbara L; Lehmler, Hans-Joachim

2009-01-01

24

A "Tail" Of Two Mines: Determining The Sources Of Lead In Mine Waters Using Pb Isotopes  

NASA Astrophysics Data System (ADS)

Acid mine drainage can be a significant environmental problem in regions where mine tailings are exposed to surface water and shallow groundwater flow. Whereas high metal concentrations in surface waters and groundwaters indicate that metals are being mobilized, these data do not uniquely identify the source of the contamination. The isotopic composition of Pb in mine waters is a superb tracer of Pb sources, because the isotopic composition of ore Pb is usually significantly different from that of host rocks, other surficial deposits, and aerosols. We have investigated metal mobility at two abandoned Pb-Zn mines in different geological settings: the sediment-hosted Sullivan Mine in southeastern British Columbia, and the New Calumet Mine of western Quebec that is hosted in metamorphic rocks of the Grenville Province. Ores from both mines have homogeneous Pb isotopic compositions that are much less radiogenic than surrounding host rocks. At Sullivan, the Pb isotopic compositions of water samples define a mixing line between Sullivan ore and at least one other more radiogenic end-member. Water samples with high Pb concentrations (0.002 to 0.3 mg/L) generally are acidic and have Pb isotope ratios equal to Sullivan ore, whereas waters with low Pb contents have near-neutral pH and have variably more radiogenic Pb isotope ratios. Thus not all the waters collected in the study area originate from Sullivan ore or mining operations, as previously thought. The dominant source of ore Pb in mine waters are the waste rock dumps. Based on their isotopic compositions, host shales or aerosols from the local Pb smelter are potential sources of non-Sullivan ore Pb; local glacial tills are an unlikely source due to their heterogeneous Pb isotopic composition. Similarly, at the New Calumet mine, water samples collected in direct contact with either ore at the surface or tailings have high Pb concentrations (up to 0.02 mg/L) and Pb isotope ratios equal to New Calumet Pb-Zn ore. However, all water samples collected downstream from the mine site have low Pb concentrations and variably more radiogenic Pb isotope ratios. Water samples from a well on the mine site and a pipe discharging water from below the tailings dam also have non-ore Pb isotope ratios. The isotopic compositions of low-Pb samples do not lie on a mixing line between ore and local host rocks, but rather lie on a mixing line between agricultural ditch and stream waters upstream of the mine and New Calumet ore. These waters may form a groundwater system flowing under the mine site that is virtually uncontaminated by the overlying ores and tailings. Compared to the Sullivan case, metals from the New Calumet ore and tailings are only weakly mobilized into local waters, probably due to buffering of waters by carbonate-bearing host rocks. We are impressed with the fingerprinting ability of Pb isotopes to track the sources of heavy metals in water systems, and suggest that other radiogenic isotopes (Sr, Nd) may also be useful in environmental studies.

Cousens, B. L.; Allen, D. M.; Lepitre, M. E.; Mortensen, J. K.; Gabites, J. E.; Nugent, M.; Fortin, D.

2004-12-01

25

Sorting signals in the MHC class II invariant chain cytoplasmic tail and transmembrane region determine trafficking to an endocytic processing compartment  

Microsoft Academic Search

Targeting of MHC class II molecules to the endocytic compartment where they encounter processed antigen is determined by the invariant chain 0i). By analysis of Ii-transferrin receptor (TR) chi- mera trafficking, we have identified sorting signals in the Ii cytoplasmic tail and transmembrane region that mediate this process. Two non-tyrosine-based sorting signals in the Ii cytoplasmic tail were identified that

C. Greg Odorizzi; Ian S. Trowbridge; Luzheng Xue; Colin R. Hopkins; Cynthia D. Davis; James E Collawnt

1994-01-01

26

Tail toy  

US Patent & Trademark Office Database

A toy having a tail attached to a flap which is tucked into clothing worn by a child at the rear so the tail appears to be part of the child. The flap is thin and has a large surface area for frictional engagement with the clothing. Both the flap and tail are soft and flexible, and the flap can detach from the clothing when the tail is pulled. In one embodiment, the flap can detach from the tail when pulled with a predetermined amount of force. Self expression, independence, knowledge and empathy for wildlife are promoted in the child by the toy. The flap can also house a story or picture relating to the animal represented by the tail, further interesting and enlightening the child.

Steiger; Vivian E. Y. (Manhattan Beach, CA)

1995-05-23

27

Animal Tails  

NSDL National Science Digital Library

Call it tail envy. With only a vestigial nub to show for ourselves, perhaps it's no wonder that animal tails capture our attention. The following Web sites present some of the more interesting tails to be found in the animal kingdom. The first Web site contains a recent article from Discovery News describing new findings that at least one species of scorpion produces two distinct types of tail venom, which have completely different effects on their victims (1). The next site from Singapore Zoological Gardens introduces the cebids (our New World monkey cousins), some of which have amazing prehensile tails that are used like a fifth limb (2). The rattlesnake is another famously-tailed creature, highlighted in the following site from the Arizona-Sonora Desert Museum (3). The site covers the main aspects of rattlesnake natural history, including a section on how the rattle forms. The Great Plains Nature Center in Wichita, Kansas, offers a Web page devoted to the beaver, including tail trivia and an audio clip of a resident beaver surprised in his den at the Kansas Wildlife Exhibit (4). Anyone who has witnessed the freakishly fascinating spectacle of a gecko leaving its tail behind to distract a would-be predator will appreciate this brief bio of the Tokay gecko, presented by ReptileCenter.com, the Herpetologist's Portal (5). Stacy's Wag'N'Train -- offering dog-training classes in San Jose, California -- provides this online guide to dog body language, which would have a very limited vocabulary without the tail (6). So, how did the peacock get its tail? It's a simple question that has driven zoologists crazy for over a century. The next Web site (7) contains an in-depth article on the subject from the Independent (London), offered through National Geographic News. And finally, the bizarre gulper eel -- able to tie its tail in several knots -- gets is own Web page on Pangea, the Web server for the Department of Educational Leadership and Technology at Southeastern Louisiana University (8). This deep-sea curiosity uses its bioluminescent tail tip to lure hapless prey into its impossibly gigantic mouth.

Sohmer, Rachel.

2003-01-01

28

MARCH7 E3 ubiquitin ligase is highly expressed in developing spermatids of rats and its possible involvement in head and tail formation.  

PubMed

Spermatogenesis is a highly complicated metamorphosis process of male germ cells. Recent studies have provided evidence that the ubiquitin-proteasome system plays an important role in sperm head shaping, but the underlying mechanism is less understood. In this study, we localized membrane-associated RING-CH (MARCH)7, an E3 ubiquitin ligase, in rat testis. Northern blot analysis showed that March7 mRNA is expressed ubiquitously but highly in the testis and ovary. In situ hybridization of rat testis demonstrated that March7 mRNA is expressed weakly in spermatogonia and its level is gradually increased as they develop. Immunohistochemical analysis detected MARCH7 protein expression in spermiogenic cells from late round spermatids to elongated spermatids and in epididymal spermatozoa. Moreover, MARCH7 was found to be localized to the caudal end of the developing acrosome of late round and elongating spermatids, colocalizing with ?-actin, a component of the acroplaxome. In addition, MARCH7 was also detected in the developing flagella and its expression levels were prominent in elongated spermatids. We also showed that MARCH7 catalyzes lysine 48 (K48)-linked ubiquitination. Immunolocalization studies revealed that K48-linked ubiquitin chains were detected in the heads of elongating spermatids and in the acrosome/acroplaxome, neck, midpiece and cytoplasmic lobes of elongated spermatids. These results suggest that MARCH7 is involved in spermiogenesis by regulating the structural and functional integrity of the head and tail of developing spermatids. PMID:23104140

Zhao, Boqiang; Ito, Kunitoshi; Iyengar, Prasanna Vasudevan; Hirose, Shigehisa; Nakamura, Nobuhiro

2012-10-27

29

Sorting signals in the MHC class II invariant chain cytoplasmic tail and transmembrane region determine trafficking to an endocytic processing compartment  

PubMed Central

Targeting of MHC class II molecules to the endocytic compartment where they encounter processed antigen is determined by the invariant chain (Ii). By analysis of Ii-transferrin receptor (TR) chimera trafficking, we have identified sorting signals in the Ii cytoplasmic tail and transmembrane region that mediate this process. Two non-tyrosine-based sorting signals in the Ii cytoplasmic tail were identified that mediate localization to plasma membrane clathrin-coated pits and promote rapid endocytosis. Leu7 and Ile8 were required for the activity of the signal most distal to the cell membrane whereas Pro15 Met16 Leu17 were important for the membrane-proximal signal. The same or overlapping non- tyrosine-based sorting signals are essential for delivery of Ii-TR chimeras, either by an intracellular route or via the plasma membrane, to an endocytic compartment where they are rapidly degraded. The Ii transmembrane region is also required for efficient delivery to this endocytic processing compartment and contains a signal distinct from the Ii cytoplasmic tail. More than 80% of the Ii-TR chimera containing the Ii cytoplasmic tail and transmembrane region is delivered directly to the endocytic pathway by an intracellular route, implying that the Ii sorting signals are efficiently recognized by sorting machinery located in the trans-Golgi.

1994-01-01

30

Determination and evaluation of an optimal dosage of carfentanil and xylazine for the immobilization of white-tailed deer (Odocoileus virginianus)  

Microsoft Academic Search

Using an iteration method, optimal hand-injected immobilization dosages of carfentanil\\/xylazine (CAR\\/XYL) were determined for 13 adult white-tailed deer (Odocoileus virginianus). Deer were temporarily restrained in a squeeze chute and were repeatedly immobilized one to four times at 2–5-wk intervals from December 2002 to March 2003. A fixed ratio of 1 mg CAR:10 mg XYL intramuscularly was used, increasing or decreasing

Timothy N. Storms; Juergen Schumacher; Nancy Zagaya; David A. Osborn; Karl V. Miller; Edward C. Ramsay

2005-01-01

31

Involvement and communication discrepancy as determinants of opinion conformity  

Microsoft Academic Search

This research studied the relationship between conformity and (a) the extent of the discrepancy between the opinions of a communicator and a recipient and (b) the degree of involvement of the recipient. These variables are central to a dissonance theory analysis of the social influence process, as well as to many previous investigations of attitude change. It can be derived

Philip G. Zimbardo

1960-01-01

32

Severe neural tube defects in the loop-tail mouse result from mutation of Lpp1, a novel gene involved in floor plate specification  

Microsoft Academic Search

Neural tube defects (NTD) are clinically important congenital malformations whose molecular mecha- nisms are poorly understood. The loop-tail ( Lp) mutant mouse provides a model for the most severe NTD, craniorachischisis, in which the brain and spinal cord remain open. During a positional cloning approach, we have identified a mutation in a novel gene, Lpp1, in the Lp mouse, providing

Jennifer N. Murdoch; Kit Doudney; Caroline Paternotte; Andrew J. Copp; Philip Stanier

2001-01-01

33

Safety of Tailings Dams  

NSDL National Science Digital Library

Contains information on different aspects of tailings dams; tailings dam properties, disasters, failure modes, slurry waves, stability analysis, and safe tailings disposal. Also includes a slope stability calculator and a tailings flow slide calculator.

2008-08-25

34

Developmental study on reduction and kinks of the tail in a new mutant knotty-tail mouse  

Microsoft Academic Search

The knotty-tail (knt\\/knt) mouse has a short and knotty tail. The tail deformity is caused by a decrease in the number of caudal vertebrae and a deformity of them in the distal part of the tail. The objective of the study was to determine how reduction and kinks of the tail region were formed during secondary body formation. By day

T. Matsuura; Isao Narama; Kiyokazu Ozaki; Masahiko Nishimura; Tomohiro Imagawa; Hiroshi Kitagawa; Masato Uehara

1998-01-01

35

Determination of thermodynamic and transport parameters of naphthenic acids and organic process chemicals in oil sand tailings pond water.  

PubMed

Oil sand tailings pond water contains naphthenic acids and process chemicals (e.g., alkyl sulphates, quaternary ammonium compounds, and alkylphenol ethoxylates). These chemicals are toxic and can seep through the foundation of the tailings pond to the subsurface, potentially affecting the quality of groundwater. As a result, it is important to measure the thermodynamic and transport parameters of these chemicals in order to study the transport behavior of contaminants through the foundation as well as underground. In this study, batch adsorption studies and column experiments were performed. It was found that the transport parameters of these chemicals are related to their molecular structures and other properties. The computer program (CXTFIT) was used to further evaluate the transport process in the column experiments. The results from this study show that the transport of naphthenic acids in a glass column is an equilibrium process while the transport of process chemicals seems to be a non-equilibrium process. At the end of this paper we present a real-world case study in which the transport of the contaminants through the foundation of an external tailings pond is calculated using the lab-measured data. The results show that long-term groundwater monitoring of contaminant transport at the oil sand mining site may be necessary to avoid chemicals from reaching any nearby receptors. PMID:23736740

Wang, Xiaomeng; Robinson, Lisa; Wen, Qing; Kasperski, Kim L

2013-07-01

36

COMET C/2011 W3 (LOVEJOY): ORBIT DETERMINATION, OUTBURSTS, DISINTEGRATION OF NUCLEUS, DUST-TAIL MORPHOLOGY, AND RELATIONSHIP TO NEW CLUSTER OF BRIGHT SUNGRAZERS  

SciTech Connect

We describe the physical and orbital properties of C/2011 W3. After surviving perihelion passage, the comet was observed to undergo major physical changes. The permanent loss of the nuclear condensation and the formation of a narrow spine tail were observed first at Malargue, Argentina, on December 20 and then systematically at Siding Spring, Australia. The process of disintegration culminated with a terminal fragmentation event on December 17.6 UT. The postperihelion dust tail, observed for {approx}3 months, was the product of activity over <2 days. The nucleus' breakup and crumbling were probably caused by thermal stress due to the penetration of the intense heat pulse deep into the nucleus' interior after perihelion. The same mechanism may be responsible for cascading fragmentation of sungrazers at large heliocentric distances. The delayed response to the hostile environment in the solar corona is at odds with the rubble-pile model, since the residual mass of the nucleus, estimated at {approx}10{sup 12} g (equivalent to a sphere 150-200 m across) just before the terminal event, still possessed nontrivial cohesive strength. The high production rates of atomic oxygen, observed shortly after perihelion, are compatible with a subkilometer-sized nucleus. The spine tail-the product of the terminal fragmentation-was a synchronic feature, whose brightest part contained submillimeter-sized dust grains, released at velocities of up to 30 m s{sup -1}. The loss of the nuclear condensation prevented an accurate orbital-period determination by traditional techniques. Since the missing nucleus must have been located on the synchrone, whose orientation and sunward tip have been measured, we compute the astrometric positions of this missing nucleus as the coordinates of the points of intersection of the spine tail's axis with the lines of forced orbital-period variation, derived from the orbital solutions based on high-quality preperihelion astrometry from the ground. The resulting orbit gives 698 {+-} 2 yr for the osculating orbital period, showing that C/2011 W3 is the first member of the expected new, 21st-century cluster of bright Kreutz-system sungrazers, whose existence was predicted by these authors in 2007. From the spine tail's evolution, we determine that its measured tip, populated by dust particles 1-2 mm in diameter, receded antisunward from the computed position of the missing nucleus. The bizarre appearance of the comet's dust tail in images taken only hours after perihelion with the coronagraphs on board the SOHO and STEREO spacecraft is readily understood. The disconnection of the comet's head from the tail released before perihelion and an apparent activity attenuation near perihelion have a common cause-sublimation of all dust at heliocentric distances smaller than about 1.8 solar radii. The tail's brightness is strongly affected by forward scattering of sunlight by dust. From an initially broad range of particle sizes, the grains that were imaged the longest had a radiation-pressure parameter {beta} {approx_equal} 0.6, diagnostic of submicron-sized silicate grains and consistent with the existence of the dust-free zone around the Sun. The role and place of C/2011 W3 in the hierarchy of the Kreutz system and its genealogy via a 14th-century parent suggest that it is indirectly related to the celebrated sungrazer X/1106 C1, which, just as the first-generation parent of C/2011 W3, split from a common predecessor during the previous return to perihelion.

Sekanina, Zdenek; Chodas, Paul W., E-mail: Zdenek.Sekanina@jpl.nasa.gov, E-mail: Paul.W.Chodas@jpl.nasa.gov [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

2012-10-01

37

Comet C/2011 W3 (Lovejoy): Orbit Determination, Outbursts, Disintegration of Nucleus, Dust-tail Morphology, and Relationship to New Cluster of Bright Sungrazers  

NASA Astrophysics Data System (ADS)

We describe the physical and orbital properties of C/2011 W3. After surviving perihelion passage, the comet was observed to undergo major physical changes. The permanent loss of the nuclear condensation and the formation of a narrow spine tail were observed first at Malargue, Argentina, on December 20 and then systematically at Siding Spring, Australia. The process of disintegration culminated with a terminal fragmentation event on December 17.6 UT. The postperihelion dust tail, observed for ~3 months, was the product of activity over <2 days. The nucleus' breakup and crumbling were probably caused by thermal stress due to the penetration of the intense heat pulse deep into the nucleus' interior after perihelion. The same mechanism may be responsible for cascading fragmentation of sungrazers at large heliocentric distances. The delayed response to the hostile environment in the solar corona is at odds with the rubble-pile model, since the residual mass of the nucleus, estimated at ~1012 g (equivalent to a sphere 150-200 m across) just before the terminal event, still possessed nontrivial cohesive strength. The high production rates of atomic oxygen, observed shortly after perihelion, are compatible with a subkilometer-sized nucleus. The spine tail—the product of the terminal fragmentation—was a synchronic feature, whose brightest part contained submillimeter-sized dust grains, released at velocities of up to 30 m s-1. The loss of the nuclear condensation prevented an accurate orbital-period determination by traditional techniques. Since the missing nucleus must have been located on the synchrone, whose orientation and sunward tip have been measured, we compute the astrometric positions of this missing nucleus as the coordinates of the points of intersection of the spine tail's axis with the lines of forced orbital-period variation, derived from the orbital solutions based on high-quality preperihelion astrometry from the ground. The resulting orbit gives 698 ± 2 yr for the osculating orbital period, showing that C/2011 W3 is the first member of the expected new, 21st-century cluster of bright Kreutz-system sungrazers, whose existence was predicted by these authors in 2007. From the spine tail's evolution, we determine that its measured tip, populated by dust particles 1-2 mm in diameter, receded antisunward from the computed position of the missing nucleus. The bizarre appearance of the comet's dust tail in images taken only hours after perihelion with the coronagraphs on board the SOHO and STEREO spacecraft is readily understood. The disconnection of the comet's head from the tail released before perihelion and an apparent activity attenuation near perihelion have a common cause—sublimation of all dust at heliocentric distances smaller than about 1.8 solar radii. The tail's brightness is strongly affected by forward scattering of sunlight by dust. From an initially broad range of particle sizes, the grains that were imaged the longest had a radiation-pressure parameter ? ~= 0.6, diagnostic of submicron-sized silicate grains and consistent with the existence of the dust-free zone around the Sun. The role and place of C/2011 W3 in the hierarchy of the Kreutz system and its genealogy via a 14th-century parent suggest that it is indirectly related to the celebrated sungrazer X/1106 C1, which, just as the first-generation parent of C/2011 W3, split from a common predecessor during the previous return to perihelion.

Sekanina, Zdenek; Chodas, Paul W.

2012-10-01

38

CCK B receptors in the periaqueductal grey are involved in electroacupuncture antinociception in the rat cold water tail-flick test  

Microsoft Academic Search

Cholecystokinin octapeptide (CCK-8) (0.25–2.0 ng), the CCKA receptor antagonist L-364,718 (60–100 ng) or the CCKB receptor antagonist L-365,260 (0.3125–1.25 ng) was administered into the periaqueductal grey (PAG) of male SD rats. The antinociceptive effect induced by electroacupuncture (EA) stimulation of different frequencies was then measured by the cold water tail-flick (CWT) test. The results showed that (1) microinjection of CCK-8

Xiao-Hong Chen; Ellen B Geller; Martin W Adler

1998-01-01

39

Using behavior theory to investigate individual-level determinants of employee involvement in TQM  

Microsoft Academic Search

Although much has been written about total quality management and employee involvement, little attention has been paid to individual-level determinants of employee's involvement in total quality management. The use of behaviour theory to formulate propositions regarding the determinants is especially scare in the total quality management and employee involvement literature. The major objective of the present research was to isolate

Zhongjun Tang; Xiaohong Chen; Zhengwen Wu

2010-01-01

40

Neurophysiological determinants of theoretical concepts and mechanisms involved in pacing.  

PubMed

Fatigue during prolonged exercise is often described as an acute impairment of exercise performance that leads to an inability to produce or maintain a desired power output. In the past few decades, interest in how athletes experience fatigue during competition has grown enormously. Research has evolved from a dominant focus on peripheral causes of fatigue towards a complex interplay between peripheral and central limitations of performance. Apparently, both feedforward and feedback mechanisms, based on the principle of teleoanticipation, regulate power output (e.g., speed) during a performance. This concept is called 'pacing' and represents the use of energetic resources during exercise, in a way such that all energy stores are used before finishing a race, but not so far from the end of a race that a meaningful slowdown can occur.It is believed that the pacing selected by athletes is largely dependent on the anticipated exercise duration and on the presence of an experientially developed performance template. Most studies investigating pacing during prolonged exercise in ambient temperatures, have observed a fast start, followed by an even pace strategy in the middle of the event with an end sprint in the final minutes of the race. A reduction in pace observed at commencement of the event is often more evident during exercise in hot environmental conditions. Further, reductions in power output and muscle activation occur before critical core temperatures are reached, indicating that subjects can anticipate the exercise intensity and heat stress they will be exposed to, resulting in a tactical adjustment of the power output. Recent research has shown that not only climatic stress but also pharmacological manipulation of the central nervous system has the ability to cause changes in endurance performance. Subjects seem to adapt their strategy specifically in the early phases of an exercise task. In high-ambient temperatures, dopaminergic manipulations clearly improve performance. The distribution of the power output reveals that after dopamine reuptake inhibition, subjects are able to maintain a higher power output compared with placebo. Manipulations of serotonin and, especially, noradrenaline, have the opposite effect and force subjects to decrease power output early in the time trial. Interestingly, after manipulation of brain serotonin, subjects are often unable to perform an end sprint, indicating an absence of a reserve capacity or motivation to increase power output. Taken together, it appears that many factors, such as ambient conditions and manipulation of brain neurotransmitters, have the potential to influence power output during exercise, and might thus be involved as regulatory mechanisms in the complex skill of pacing. PMID:23456493

Roelands, Bart; de Koning, Jos; Foster, Carl; Hettinga, Floor; Meeusen, Romain

2013-05-01

41

Environmentally safe design of tailing dams for the management of iron ore tailings in Indian context.  

PubMed

The need for the disposal of iron ore tailings in an enviornmentally firiendly manner is of great concern. This paper investigates the soil engineering properties for the construction of iron ore tailing dam, its foundation, construction materials and design data used for the construction analysis of the tailing dam. Geophysical investigations were carried out to establish the bedrock below the spillway. A computer programme taking into account the Swedish Slip Circle Method of analysis was used in the stability analysis of dam. It also focuses on the charactierstics of the tailings reponsible for the determination of optimum size of tailing pond for the containment of the tailings. The studies on the settling characteristics of tailings indicate much less area in comparison to the area provided in the existing tailing ponds in India. In the proposed scheme, it is suggested to provide an additional unit of sedimentation tank before the disposal of tailings to the tailing pond. PMID:17051916

Ghose, Mrinal K; Sen, P K

2005-10-01

42

THE MALE FASHION CONSUMER: AN ANALYSIS OF FASHION INVOLVEMENT AND RETAIL PATRONAGE DETERMINANTS  

Microsoft Academic Search

The objective of the dissertation research was to profile adult male fashion involvement; to measure determinants of patronage for a major metropolitan marketplace; and to relate adult male fashion involvement to retail shopping behavior.^ The research methodology involved the development and administration of an eight-page questionnaire to 1,025 adult male heads of households in the Toronto, Ontario, Canada Census Metropolitan

LAWRENCE JEAN RING

1977-01-01

43

Pattern and Determinants of Paternal Involvement in Childcare: An Empirical Investigation in a Metropolis of India  

Microsoft Academic Search

An analysis of various aspects of paternal involvement among Indian fathers is presented in this article. The pattern of involvement\\u000a in terms of the activities participated in, and their frequency of participation have been examined. Overall level of involvement\\u000a of fathers in childcare has also been determined. A number of hypotheses regarding predictors of paternal involvement have\\u000a been formulated and

Anjula Saraff; Harish C. Srivastava

2010-01-01

44

Interaction surface and topology of Get3-Get4-Get5 protein complex, involved in targeting tail-anchored proteins to endoplasmic reticulum.  

PubMed

Recent work has uncovered the "GET system," which is responsible for endoplasmic reticulum targeting of tail-anchored proteins. Although structural information and the individual roles of most components of this system have been defined, the interactions and interplay between them remain to be elucidated. Here, we investigated the interactions between Get3 and the Get4-Get5 complex from Saccharomyces cerevisiae. We show that Get3 interacts with Get4-Get5 via an interface dominated by electrostatic forces. Using isothermal titration calorimetry and small-angle x-ray scattering, we further demonstrate that the Get3 homodimer interacts with two copies of the Get4-Get5 complex to form an extended conformation in solution. PMID:22190685

Chang, Yi-Wei; Lin, Tai-Wen; Li, Yi-Chuan; Huang, Yu-Shan; Sun, Yuh-Ju; Hsiao, Chwan-Deng

2011-12-21

45

Structure of the Sgt2 dimerization domain complexed with the Get5 UBL domain involved in the targeting of tail-anchored membrane proteins to the endoplasmic reticulum.  

PubMed

The insertion of tail-anchored membrane (TA) proteins into the appropriate membrane is a post-translational event that requires stabilization of the transmembrane domain and targeting to the proper destination. Sgt2, a small glutamine-rich tetratricopeptide-repeat protein, is a heat-shock protein cognate (HSC) co-chaperone that preferentially binds endoplasmic reticulum-destined TA proteins and directs them to the GET pathway via Get4 and Get5. The N-terminal domain of Sgt2 seems to exert dual functions. It mediates Get5 interaction and allows substrate delivery to Get3. Following the N-terminus of Get5 is a ubiquitin-like (Ubl) domain that interacts with the N-terminus of Sgt2. Here, the crystal structure of the Sgt2 dimerization domain complexed with the Get5 Ubl domain (Sgt2N-Get5Ubl) is reported. This complex reveals an intimate interaction between one Sgt2 dimer and one Get5 monomer. This research further demonstrates that hydrophobic residues from both Sgt2 and Get5 play an important role in cell survival under heat stress. This study provides detailed molecular insights into the specific binding of this GET-pathway complex. PMID:24100326

Tung, Jung Yu; Li, Yi Chuan; Lin, Tai Wen; Hsiao, Chwan Deng

2013-09-20

46

A disorder-to-order structural transition in the COOH-tail of Fz4 determines misfolding of the L501fsX533-Fz4 mutant.  

PubMed

Frizzled 4 belongs to the superfamily of G protein coupled receptors. The unstructured cytosolic tail of the receptor is essential for its activity. The mutation L501fsX533 in the fz4 gene results in a new COOH-tail of the receptor and causes a form of Familial exudative vitreoretinopathy. Here we show that the mutated tail is structured. Two amphipathic helices, displaying affinity for membranes and resembling the structure of Influenza Hemagglutinin fusion peptide, constitute the new fold. This tail induces the aggregation of the receptor in the Endoplasmic Reticulum and it is sufficient to block the export to the Golgi of a chimeric VSVG protein containing the mutated tail. Affecting the tail's structure, net charge or amphipathicity relocates the mutated Fz4 receptor to the Plasma Membrane. Such disorder-to-order structural transition was never described in GPCRs and opens a new scenario on the possible effect of mutations on unstructured regions of proteins. PMID:24036468

Lemma, Valentina; D'Agostino, Massimo; Caporaso, Maria Gabriella; Mallardo, Massimo; Oliviero, Giorgia; Stornaiuolo, Mariano; Bonatti, Stefano

2013-09-16

47

Tail position affects the body temperature of rats during cold exposure in a low-energy state.  

PubMed

Rats place their tails underneath their body trunks when cold (tail-hiding behavior). The aim of the present study was to determine whether this behavior is necessary to maintain body temperature. Male Wistar rats were divided into 'fed' and '42-h fasting' groups. A one-piece tail holder (8.4 cm in length) that prevented the tail-hiding behavior or a three-piece tail holder (2.8 cm in length) that allowed for the tail-hiding behavior was attached to the tails of the rats. The rats were exposed to 27°C for 180 min or to 20°C for 90 min followed by 15°C for 90 min with continuous body temperature and oxygen consumption measurements. Body temperature decreased by -1.0 ± 0.1°C at 15°C only in the rats that prevented tail-hiding behavior of the 42-h fasting group, and oxygen consumption increased at 15°C in all animals. Oxygen consumption was not different between the rats that prevented tail-hiding behavior and the rats that allowed the behavior in the fed and 42-h fasting groups under ambient conditions. These results show that the tail-hiding behavior is involved in thermoregulation in the cold in fasting rats. PMID:22037912

Uchida, Yuki; Tokizawa, Ken; Nakamura, Mayumi; Lin, Cheng-Hsien; Nagashima, Kei

2011-10-29

48

Innovativeness and Involvement as Determinants of Website Loyalty: III. Theoretical and managerial contributions  

Microsoft Academic Search

This paper is the third of the series of studies entitled “Innovativeness and Involvement as Determinants of Website Loyalty”, which was designed to test Foxall's [1995. Cognitive styles of consumer initiators. Technovation 15(5), 269–288] style\\/involvement model in the context of Internet buyer behaviours. This paper aims to demonstrate the theoretical and managerial contributions of Foxall's (1995) style\\/involvement by reviewing the

Hui-Chih Wang; John G. Pallister; Gordon R. Foxall

2006-01-01

49

Multiple cholesterol recognition/interaction amino acid consensus (CRAC) motifs in cytosolic C tail of Slo1 subunit determine cholesterol sensitivity of Ca2+- and voltage-gated K+ (BK) channels.  

PubMed

Large conductance, Ca(2+)- and voltage-gated K(+) (BK) channel proteins are ubiquitously expressed in cell membranes and control a wide variety of biological processes. Membrane cholesterol regulates the activity of membrane-associated proteins, including BK channels. Cholesterol modulation of BK channels alters action potential firing, colonic ion transport, smooth muscle contractility, endothelial function, and the channel alcohol response. The structural bases underlying cholesterol-BK channel interaction are unknown. Such interaction is determined by strict chemical requirements for the sterol molecule, suggesting cholesterol recognition by a protein surface. Here, we demonstrate that cholesterol action on BK channel-forming Cbv1 proteins is mediated by their cytosolic C tail domain, where we identified seven cholesterol recognition/interaction amino acid consensus motifs (CRAC4 to 10), a distinct feature of BK proteins. Cholesterol sensitivity is provided by the membrane-adjacent CRAC4, where Val-444, Tyr-450, and Lys-453 are required for cholesterol sensing, with hydrogen bonding and hydrophobic interactions participating in cholesterol location and recognition. However, cumulative truncations or Tyr-to-Phe substitutions in CRAC5 to 10 progressively blunt cholesterol sensitivity, documenting involvement of multiple CRACs in cholesterol-BK channel interaction. In conclusion, our study provides for the first time the structural bases of BK channel cholesterol sensitivity; the presence of membrane-adjacent CRAC4 and the long cytosolic C tail domain with several other CRAC motifs, which are not found in other members of the TM6 superfamily of ion channels, very likely explains the unique cholesterol sensitivity of BK channels. PMID:22474334

Singh, Aditya K; McMillan, Jacob; Bukiya, Anna N; Burton, Brittany; Parrill, Abby L; Dopico, Alex M

2012-04-03

50

Paraprofessional Involvement in Self-Determination Instruction for Students with High-Incidence Disabilities  

ERIC Educational Resources Information Center

|Although enhancing students' self-determination is advocated as a central element of high-quality special education and transition services, little is known about the ways in which paraprofessionals are involved in promoting self-determination or the extent to which they share teachers' views regarding its importance. The authors surveyed 223…

Lane, Kathleen Lynne; Carter, Erik W.; Sisco, Lynn

2012-01-01

51

Hysteresis-Induced Long-Time Tails  

NASA Astrophysics Data System (ADS)

It is shown analytically that the output of the standard model for complex, nonlocal hysteresis, the Preisach model, exhibits long-time tails under quite general conditions. For uncorrelated input signals the exponent of the algebraic output correlation decay is determined solely by the tails of the input and the Preisach density. Correspondingly we identify universality classes leading to identical algebraic tails. These results predict the occurrence of 1/f noise for a large class of hysteretic systems.

Radons, Günter

2008-06-01

52

Heads for learning, tails for memory: reward, reinforcement and a role of dopamine in determining behavioral relevance across multiple timescales  

PubMed Central

Dopamine has long been tightly associated with aspects of reinforcement learning and motivation in simple situations where there are a limited number of stimuli to guide behavior and constrained range of outcomes. In naturalistic situations, however, there are many potential cues and foraging strategies that could be adopted, and it is critical that animals determine what might be behaviorally relevant in such complex environments. This requires not only detecting discrepancies with what they have recently experienced, but also identifying similarities with past experiences stored in memory. Here, we review what role dopamine might play in determining how and when to learn about the world, and how to develop choice policies appropriate to the situation faced. We discuss evidence that dopamine is shaped by motivation and memory and in turn shapes reward-based memory formation. In particular, we suggest that hippocampal-striatal-dopamine networks may interact to determine how surprising the world is and to either inhibit or promote actions at time of behavioral uncertainty.

Baudonnat, Mathieu; Huber, Anna; David, Vincent; Walton, Mark E.

2013-01-01

53

Magnetohydrodynamics of Mira's cometary tail  

NASA Astrophysics Data System (ADS)

Aims: The asymptotic giant-branch, long-period variable star Mira exhibits a 4 parsec long cometary tail in the far-ultraviolet. We address the issue of the origin of this structure and its emission process by simulating the transition of this star from the interstellar medium to the Local Bubble, which is a tenuous, high-pressure medium. Methods: We use the hydrodynamic and the magnetohydrodynamic modules of the PLUTO astrophysical code to carry out our simulations. We study the system without a cooling function, with a simplified exponential cooling function, and with a simplified nonequilibrium cooling function. Results: We find evidence that magnetohydrodynamics constrain the shape of the cometary tail and explain features of its far-ultraviolet emission. We suggest an emission process that involves C0 excitation through inelastic electron collisions and a two-photon continuum to explain the luminosity of Mira's tail.

Gómez, E. A.

2013-10-01

54

Remediation of Tailings Dams  

Microsoft Academic Search

\\u000a Tailings are a waste product of mining activities. The ore is crushed in processing to a size less than 0.1 to 1.0 mm, the\\u000a metal content is removed, and the remaining product is called tailings. Normally, the tailings will be pumped as slurry to\\u000a a sedimentation pond that is surrounded by dams and, sometimes, natural heights that form a tailings

A. G. Benckert

55

Molecular determinants involved in the allosteric control of agonist affinity in the GABAB receptor by the GABAB2 subunit.  

PubMed

The gamma-aminobutyric acid type B (GABAB) receptor is an allosteric complex made of two subunits, GABAB1 (GB1) and GABAB2 (GB2). Both subunits are composed of an extracellular Venus flytrap domain (VFT) and a heptahelical domain (HD). GB1 binds GABA, and GB2 plays a major role in G-protein activation as well as in the high agonist affinity state of GB1. How agonist affinity in GB1 is regulated in the receptor remains unknown. Here, we demonstrate that GB2 VFT is a major molecular determinant involved in this control. We show that isolated versions of GB1 and GB2 VFTs in the absence of the HD and C-terminal tail can form hetero-oligomers as shown by time-resolved fluorescence resonance energy transfer (based on HTRF technology). GB2 VFT and its association with GB1 VFT controlled agonist affinity in GB1 in two ways. First, GB2 VFT exerted a direct action on GB1 VFT, as it slightly increased agonist affinity in isolated GB1 VFT. Second and most importantly, GB2 VFT prevented inhibitory interaction between the two main domains (VFT and HD) of GB1. According to this model, we propose that GB1 HD prevents the possible natural closure of GB1 VFT. In contrast, GB2 VFT facilitates this closure. Finally, such inhibitory contacts between HD and VFT in GB1 could be similar to those important to maintain the inactive state of the receptor. PMID:14736871

Liu, Jianfeng; Maurel, Damien; Etzol, Sébastien; Brabet, Isabelle; Ansanay, Hervé; Pin, Jean-Philippe; Rondard, Philippe

2004-01-21

56

Specific Histone Tail Modification and Not DNA Methylation Is a Determinant of Herpes Simplex Virus Type 1 Latent Gene Expression  

PubMed Central

During herpes simplex virus type 1 (HSV-1) latency, gene expression is tightly repressed except for the latency-associated transcript (LAT). The mechanistic basis for this repression is unknown, but its global nature suggests regulation by an epigenetic mechanism such as DNA methylation. Previous work demonstrated that latent HSV-1 genomes are not extensively methylated, but these studies lacked the resolution to examine methylation of individual CpGs that could repress transcription from individual promoters during latency. To address this point, we employed established models to predict genomic regions with the highest probability of being methylated and, using bisulfite sequencing, analyzed the methylation profiles of these regions. We found no significant methylation of latent DNA isolated from mouse dorsal root ganglia in any of the regions examined, including the ICP4 and LAT promoters. This analysis indicates that methylation is unlikely to play a major role in regulating HSV-1 latent gene expression. Subsequently we focused on differential histone modification as another epigenetic mechanism that could regulate latent transcription. Chromatin immunoprecipitation analysis of the latent HSV-1 DNA repeat regions demonstrated that a portion of the LAT region is associated with histone H3 acetylated at lysines 9 and 14, consistent with a euchromatic and nonrepressed structure. In contrast, the chromatin associated with the HSV-1 DNA polymerase gene located in the unique long segment was not enriched in H3 acetylated at lysines 9 and 14, suggesting a transcriptionally inactive structure. These data suggest that histone composition may be a major regulatory determinant of HSV latency.

Kubat, Nicole J.; Tran, Robert K.; McAnany, Peterjon; Bloom, David C.

2004-01-01

57

Length of Magnetospheric Tail  

Microsoft Academic Search

It is shown that hydromagnetic waves, through the action of radiation pressure, can prevent the tail of the magnetosphere from closing near the earth. It is argued that the tail of the magnetosphere may be 20 to 50 AU long. The tail can close at such heliocentric distances in the charge-exchange boundary shell where the solar wind is terminated and

A. J. Dessler

1964-01-01

58

Human Tail and Myelomeningocele  

Microsoft Academic Search

The human tail is rarely reported and is usually associated with underlying spina bifida occulta. A male newborn presenting a caudal appendage (human tail) with skin-covered myelomeningocele and tethered cord is described. Surgical excision of the human tail and repair of the myelomeningocele were performed 3 days after birth. After the operation, the patient had an uneventful convalescence and received

Pei-Jung Lin; Yu-Tang Chang; Hsing-I Tseng; Jan-You Lin; Yu-Sheng Huang

2007-01-01

59

8 CFR 208.31 - Reasonable fear of persecution or torture determinations involving aliens ordered removed under...  

Code of Federal Regulations, 2010 CFR

...false Reasonable fear of persecution or torture determinations involving aliens ordered...31 Reasonable fear of persecution or torture determinations involving aliens ordered...relevant to the possibility of persecution or torture. The alien's...

2009-01-01

60

8 CFR 208.31 - Reasonable fear of persecution or torture determinations involving aliens ordered removed under...  

Code of Federal Regulations, 2010 CFR

...false Reasonable fear of persecution or torture determinations involving aliens ordered...31 Reasonable fear of persecution or torture determinations involving aliens ordered...relevant to the possibility of persecution or torture. The alien's...

2010-01-01

61

Study of decays involving kaons, spectral functions and determination of the strange quark mass  

Microsoft Academic Search

.   All ALEPH measurements of branching ratios of decays involving kaons are summarized including a combination of results obtained with and detection. The decay dynamics are studied, leading to the determination of contributions from vector and , and axial-vector and resonances. Agreement with isospin symmetry is observed among the different final states. Under the hypothesis of the conserved\\u000a vector current,

D. Decamp; P. Ghez; C. Goy; J P Lees; E Merle; M N Minard; B Pietrzyk; R Alemany; M P Casado; M Chmeissani; J M Crespo; E Fernández; M Fernández-Bosman; L Garrido; E Graugès-Pous; A Juste; M Martínez; G Merino; R Miquel; L M Mir; A Pacheco; I C Park; I Riu; A Colaleo; D Creanza; M De Palma; G Gelao; Giuseppe Iaselli; G Maggi; M Maggi; S Nuzzo; A Ranieri; G Raso; F Ruggieri; G Selvaggi; L Silvestris; P Tempesta; A Tricomi; G Zito; X Huang; J Lin; Q Ouyang; T Wang; Y Xie; R Xu; S Xue; J Zhang; L Zhang; W Zhao; D Abbaneo; U Becker; G Boix; M Cattaneo; V Ciulli; G Dissertori; H Drevermann; Roger W Forty; M Frank; A W Halley; J B Hansen; J Harvey; P Janot; B Jost; Ivan Lehraus; O Leroy; P Mato; Adolf G Minten; A Moutoussi; F Ranjard; Luigi Rolandi; D Rousseau; W D Schlatter; M Schmitt; O Schneider; W Tejessy; F Teubert; I R Tomalin; E Tournefier; Ziad J Ajaltouni; F Badaud; G Chazelle; O Deschamps; A Falvard; C Ferdi; P Gay; C Guicheney; P Henrard; J Jousset; B Michel; S Monteil; J C Montret; D Pallin; P Perret; F Podlyski; J D Hansen; P H Hansen; B S Nilsson; B Rensch; A Wäänänen; G Daskalakis; A Kyriakis; C Markou; Errietta Simopoulou; I Siotis; Anna Vayaki; A Blondel; G R Bonneaud; J C Brient; A Rougé; M Rumpf; M Swynghedauw; M Verderi; H L Videau; E Focardi; G Parrini; K Zachariadou; R J Cavanaugh; M Corden; C H Georgiopoulos; A Antonelli; G Bencivenni; G Bologna; F Bossi; P Campana; G Capon; F Cerutti; V Chiarella; P Laurelli; G Mannocchi; F Murtas; G P Murtas; L Passalacqua; M Pepé-Altarelli; L Curtis; J G Lynch; P Negus; V O'Shea; C Raine; P Teixeira-Dias; A S Thompson; O L Buchmüller; S Dhamotharan; C Geweniger; P Hanke; G Hansper; V Hepp; E E Kluge; A Putzer; J Sommer; K Tittel; S Werner; M Wunsch; R Beuselinck; David M Binnie; W Cameron; Peter J Dornan; M Girone; S M Goodsir; E B Martin; N Marinelli; J K Sedgbeer; P Spagnolo; E Thomson; M D Williams; V M Ghete; P Girtler; E Kneringer; D Kuhn; G Rudolph; A P Betteridge; C K Bowdery; P G Buck; P Colrain; G Crawford; A J Finch; F Foster; G Hughes; R W L Jones; N A Robertson; I Giehl; C Hoffmann; K Jakobs; K Kleinknecht; G Quast; B Renk; E Rohne; H G Sander; P Van Gemmeren; H W Wachsmuth; C Zeitnitz; Jean-Jacques Aubert; C Benchouk; A Bonissent; J Carr; P Coyle; F Etienne; A Ealet; F Motsch; P Payre; M Talby; M Thulasidas; M Aleppo; M Antonelli; F Ragusa; R Berlich; V Büscher; H Dietl; G Ganis; K Hüttmann; G Lütjens; C Mannert; W Männer; H G Moser; S Schael; Ronald Settles; H C J Seywerd; H Stenzel; W Wiedenmann; G Wolf; J Boucrot; O Callot; S Chen; A Cordier; M Davier; L Duflot; J F Grivaz; P Heusse; A Höcker; A Jacholkowska; D W Kim; F R Le Diberder; J Lefrançois; A M Lutz; M H Schune; J J Veillet; I Videau; D Zerwas; P Azzurri; G Bagliesi; S Bettarini; T Boccali; C Bozzi; G Calderini; R Dell'Orso; R Fantechi; I Ferrante; L Foà; A Giassi; A Gregorio; F Ligabue; A Lusiani; P S Marrocchesi; A Messineo; Fabrizio Palla; G Rizzo; G Sanguinetti; A Sciabà; G Sguazzoni; Roberto Tenchini; C Vannini; A Venturi; P G Verdini; G A Blair; J T Chambers; G D Cowan; M G Green; T Medcalf; J A Strong; J H Von Wimmersperg-Töller; David R Botterill; R W Clifft; T R Edgecock; P R Norton; J C Thompson; A E Wright; B Bloch-Devaux; P Colas; S Emery; Witold Kozanecki; E Lançon; M C Lemaire; E Locci; P Pérez; J Rander; J F Renardy; A Roussarie; J P Schuller; J Schwindling; A Trabelsi; B Vallage; S N Black; J H Dann; R P Johnson; H Y Kim; N P Konstantinidis; A M Litke; M A McNeil; G Taylor; C N Booth; S L Cartwright; F Combley; M S Kelly; M H Lehto; L F Thompson; K Affholderbach; A Böhrer; S Brandt; J Foss; Claus Grupen; G Prange; L Smolik; F Stephan; G Giannini; B Gobbo; J E Rothberg; S R Wasserbaech; S R Armstrong; E Charles; P Elmer; D P S Ferguson; Y Gao; S González; T C Greening; O J Hayes; H Hu; S Jin; G Mamier; P A McNamara; J M Nachtman; J Nielsen; W Orejudos; Y B Pan; Y Saadi; I J Scott; M Vogt; J Walsh; Wu Sau Lan; X Wu; G Zobernig

1999-01-01

62

Identification of the C/EBP? C-terminal tail residues involved in the protein interaction with GABP and their potency in myeloid differentiation of K562 cells.  

PubMed

The CCAAT/enhancer-binding protein ? (C/EBP?) is the member of a family of related basic leucine zipper (bZIP) transcription factors and is critical for granulopoiesis. We previously demonstrated that C/EBP? interacts with the ETS domain of widely expressed GABP?, which leads to cooperative transcriptional activation of the myeloid-specific promoter for human FCAR encoding the Fc receptor for IgA (Fc?R, CD89) in part by facilitating recruitment of C/EBP? to the promoter. The C/EBP? molecule contains transactivation domains (TADs) at its N-terminus and a DNA-binding and dimerization bZIP structure at its C-terminus. We demonstrate here that GABP? interacts with the last 18 residues of the C/EBP? C-terminus beyond the bZIP DNA-binding and dimerizing region. Deletion of this C-terminus resulted in loss of GABP? interaction but not affecting its DNA binding ability, indicating that it is not required for homodimer formation. Moreover, the C-terminus confers the ability to functionally synergize with GABP on a heterologous TAD when fused to the C-terminus of the VP16 TAD. We identified a three-amino acid stretch (amino acids 341-343) that is important for both functional and protein interactions with GABP. Ectopic expression in K562 cells of C/EBP? mutant incapable of interacting with GABP? does not induce expression of granulocytic differentiation markers including CD15, CD11b, GCSF-R and C/EBP?, and does not inhibit proliferation, whereas wild type does. These results demonstrate the functional importance of the C/EBP? C-terminus beyond the bZIP DNA-binding and dimerization region, which may mediate cooperative activation by C/EBP? and GABP of myeloid-specific genes involved in C/EBP?-dependent granulopoiesis. PMID:24076158

Shimokawa, Toshibumi; Nunomura, Satoshi; Fujisawa, Daisuke; Ra, Chisei

2013-09-27

63

Receptor specificity of the short tail fibres (gp12) of T-even type Escherichia coli phages  

Microsoft Academic Search

Short tail fibres of T-even like phages are involved in host recognition. To determine the specificity of the fibres, the region containing gene 12 of phages T2, K3, and K3hx was cloned. The genes 11, 12, wac, and 13, coding for the baseplate outer wedge, short tail fibres, collar wishes, and a head completion component, respectively, were localized on the

Isolde Riede

1987-01-01

64

Characterization of the Distal Tail Fiber Locus and Determination of the Receptor for Phage AR1, Which Specifically Infects Escherichia coli O157:H7  

PubMed Central

Phage AR1 is similar to phage T4 in several essential genes but differs in host range. AR1 infects various isolates of Escherichia coli O157:H7 but does not infect K-12 strains that are commonly infected by T4. We report here the determinants that confer this infection specificity. In T-even phages, gp37 and gp38 are components of the tail fiber that are critical for phage-host interaction. The counterparts in AR1 may be similarly important and, therefore, were characterized. The AR1 gp37 has a sequence that differs totally from those of T2 and T4, except for a short stretch at the N terminus. The gp38 sequence, however, has some conservation between AR1 and T2 but not between AR1 and T4. The sequences that are most closely related to the AR1 gp37 and gp38 are those of phage Ac3 in the T2 family. To identify the AR1-specific receptor, E. coli O157:H7 was mutated by Tn10 insertion and selected for an AR1-resistant phenotype. A mutant so obtained has an insertion occurring at ompC that encodes an outer membrane porin. To confirm the role of OmpC in the AR1 infection, homologous replacement was used to create an ompC disruption mutant (RM). When RM was complemented with OmpC originated from an O157:H7 strain, but not from K-12, its AR1 susceptibility was fully restored. Our results suggest that the host specificity of AR1 is mediated at least in part through the OmpC molecule.

Yu, Sung-Liang; Ko, Kai-Liang; Chen, Chang-Shi; Chang, Yu-Chung; Syu, Wan-Jr

2000-01-01

65

Organization and Nucleotide Sequence Determination of a Gene Cluster Involved in 3-chlorocatechol Degradation  

Microsoft Academic Search

Three critical enzymes, catechol oxygenase II (chlorocatechol dioxygenase), muconate cycloisomerase II, and dienelactone hydrolase, are involved in the degradation of chlorocatechols, which are obligatory intermediates in the catabolism of chlorinated aromatic compounds. The organization and complete nucleotide sequence of the genes for these enzymes have been determined on a 4.2-kilobase-pair (kbp) Bgl II fragment cloned from the plasmid pAC27, based

B. Frantz; A. M. Chakrabarty

1987-01-01

66

Mass Transport of Proform of a Kdel-Tailed Cysteine Proteinase (Sh-EP) to Protein Storage Vacuoles by Endoplasmic Reticulum-Derived Vesicle Is Involved in Protein Mobilization in Germinating Seeds  

PubMed Central

A vacuolar cysteine proteinase, designated SH-EP, is expressed in the cotyledon of germinated Vigna mungo seeds and is responsible for the degradation of storage proteins. SH-EP is a characteristic vacuolar proteinase possessing a COOH-terminal endoplasmic reticulum (ER) retention sequence, KDEL. In this work, immunocytochemical analysis of the cotyledon cells of germinated V. mungo seeds was performed using seven kinds of antibodies to identify the intracellular transport pathway of SH-EP from ER to protein storage vacuoles. A proform of SH-EP synthesized in ER accumulated at the edge or middle region of ER where the transport vesicle was formed. The vesicle containing a large amount of proSH-EP, termed KV, budded off from ER, bypassed the Golgi complex, and was sorted to protein storage vacuoles. This massive transport of SH-EP via KV was thought to mediate dynamic protein mobilization in the cotyledon cells of germinated seeds. We discuss the possibilities that the KDEL sequence of KDEL-tailed vacuolar cysteine proteinases function as an accumulation signal at ER, and that the mass transport of the proteinases by ER-derived KV-like vesicle is involved in the protein mobilization of plants.

Toyooka, Kiminori; Okamoto, Takashi; Minamikawa, Takao

2000-01-01

67

Tails of Bacterial Motility  

NASA Astrophysics Data System (ADS)

The cytoplasm of living cells provides a complex fluid environment in which intracellular bacteria live and move. By analyzing the easily visible curved actin ``comet-tail'' of polymerization-based-motility bacteria such as Listeria monocytogenes, we can learn about sub-micron structure and dynamics of the tail and of the bacterial surface enzyme that catalyzes tail formation. By characterizing the motility, we can transform such motile systems into probes of the cytoplasmic environment.

Rutenberg, Andrew; Grant, Martin

2001-03-01

68

Investigation Of The Use Of Mine Tailings For Unpaved Road Base  

Microsoft Academic Search

Tailings have been traditionally stored in ponds surrounded by tailings dams for many years but since many accidents, including fatal ones, took place that involved tailings dams, a new approach has become necessary for their storage. An approach devised by Robinsky in the early seventies for the storage and disposal of mine tailings suggests that it is more advantageous environmentally

Ali A. Mahmood; Catherine N. Mulligan

2010-01-01

69

Floods from tailings dam failures  

Microsoft Academic Search

This paper compiles the available information on historic tailings dam failures with the purpose to establish simple correlations between tailings ponds geometric parameters (e.g., dam height, tailings volume) and the hydraulic characteristics of floods resulting from released tailings. Following the collapse of a mining waste dam, only a part of tailings and polluted water stored at the dam is released,

M. Rico; G. Benito; A. Díez-Herrero

2008-01-01

70

Determination of Sites Involved, HIV Co-Infection & Utility of Diagnostic Modalities in EPTB  

PubMed Central

Background: Tuberculosis remains a major global public health problem and an on-going epidemic. Though the chief objectives of the Revised National Tuberculosis Control Programme (RNTCP) in detecting and curing the infectious pulmonary cases is well taken, there has been a steady rise in the number of Extra Pulmonary Tuberculosis (EPTB) cases as documented in several studies. EPTB which usually constitutes around 15%-20% of the total TB cases is now being increasingly reported due to a combination of better diagnostic facilities, and the HIV pandemic. Though several studies have shown increasing prevalence of EPTB, only few studies are available, especially in the Indian scenario, that study the pattern and risk factors. Hence, this retrospective observational study was undertaken to determine the sites of the involvement, HIV co-infection and usefulness of various diagnostic modalities in EPTB affecting patients attending a medical college DOTS clinic. Material and Methods: One hundred ten EPTB patients referred to the DOTS clinics of the TB & Chest department from the period Dec 2010– Mar 2012 were included in the study. The diagnosis of EPTB was established by combined clinical, microbiological, histopathological &/or imaging modalities. Their medical records were assessed to determine the age distribution, gender and anatomical sites of involvement. The presence of co-morbid conditions like smoking history, alcoholism, diabetic and HIV status were noted. BCG status and Mantoux test readings were recorded. The different diagnostic tests used in confirming EPTB at different sites were recorded. Chest x-ray was analysed for all patients to assess coexisting pulmonary involvement. All patients were followed to assess the outcome of treatment. Results: The mean age of patients was 34.4. The male to female ratio was 58:52 showing a slight male predominance. The most common site of involvement was lymph node followed by pleural effusion and abdominal TB. The prevalence of lymph node TB was noted to be higher in female patients as compared to other sites of EPTB. Mantoux test was positive in 57 (51.8%) patients. HIV co-infection was noted in only 3 (2.7%) patients. Concomitant pulmonary involvement was seen in 19 (17.3%) patients. Conclusions: Lymph node was the most common site involvement showing a significant female preponderance followed by pleural effusion and abdominal TB. The rates of HIV co-infection and diabetes mellitus were 2.7% and 20% respectively. The most useful diagnostic modality was tissue sampling followed by imaging. Mantoux test is not unequivocal for the diagnosis of EPTB.

Shanmuganathan, Aruna; R, Srinivasan; G, Thilagavathy; D, Satishkumar; C, Sidduraj; James, Bonny

2013-01-01

71

Determination of Sites Involved, HIV Co-Infection & Utility of Diagnostic Modalities in EPTB.  

PubMed

Background: Tuberculosis remains a major global public health problem and an on-going epidemic. Though the chief objectives of the Revised National Tuberculosis Control Programme (RNTCP) in detecting and curing the infectious pulmonary cases is well taken, there has been a steady rise in the number of Extra Pulmonary Tuberculosis (EPTB) cases as documented in several studies. EPTB which usually constitutes around 15%-20% of the total TB cases is now being increasingly reported due to a combination of better diagnostic facilities, and the HIV pandemic. Though several studies have shown increasing prevalence of EPTB, only few studies are available, especially in the Indian scenario, that study the pattern and risk factors. Hence, this retrospective observational study was undertaken to determine the sites of the involvement, HIV co-infection and usefulness of various diagnostic modalities in EPTB affecting patients attending a medical college DOTS clinic. Material and Methods: One hundred ten EPTB patients referred to the DOTS clinics of the TB & Chest department from the period Dec 2010- Mar 2012 were included in the study. The diagnosis of EPTB was established by combined clinical, microbiological, histopathological &/or imaging modalities. Their medical records were assessed to determine the age distribution, gender and anatomical sites of involvement. The presence of co-morbid conditions like smoking history, alcoholism, diabetic and HIV status were noted. BCG status and Mantoux test readings were recorded. The different diagnostic tests used in confirming EPTB at different sites were recorded. Chest x-ray was analysed for all patients to assess coexisting pulmonary involvement. All patients were followed to assess the outcome of treatment. Results: The mean age of patients was 34.4. The male to female ratio was 58:52 showing a slight male predominance. The most common site of involvement was lymph node followed by pleural effusion and abdominal TB. The prevalence of lymph node TB was noted to be higher in female patients as compared to other sites of EPTB. Mantoux test was positive in 57 (51.8%) patients. HIV co-infection was noted in only 3 (2.7%) patients. Concomitant pulmonary involvement was seen in 19 (17.3%) patients. Conclusions: Lymph node was the most common site involvement showing a significant female preponderance followed by pleural effusion and abdominal TB. The rates of HIV co-infection and diabetes mellitus were 2.7% and 20% respectively. The most useful diagnostic modality was tissue sampling followed by imaging. Mantoux test is not unequivocal for the diagnosis of EPTB. PMID:24086863

Shanmuganathan, Aruna; R, Srinivasan; G, Thilagavathy; D, Satishkumar; C, Sidduraj; James, Bonny

2013-08-01

72

Knowledge Long Tail  

Microsoft Academic Search

This paper proposes an approach to visualize the benefits of applying contemporary technology in explicit knowledge management processes. The “Knowledge Long Tail” is a novel way of categorizing individual and organizational knowledge, and of modeling knowledge in organizations in terms of its type and frequency of use. The concept is inspired by the market long tail phenomenon raised by Chris

I. Lin; R. H. A. Seidel; D. Howell; D. Walker

2010-01-01

73

The human tail  

Microsoft Academic Search

The human tail is a congenital anomaly with a protruding lesion from the lumbosacrococcygeal region. A newborn with a tail-like structure over the coccygeal area observed since birth is presented. Lipoma accompanied by tethered spinal cord were found. In reviewing the literature from 1960 to 1997, 59 cases were described. Higher incidences of spinal dysraphism (49.15%) and tethered spinal cord

Frank L Lu; Pen-Jung Wang; Ru-Jeng Teng; Kuo-Inn Tsou Yau

1998-01-01

74

Reported tailings dam failures  

Microsoft Academic Search

A detailed search and re-evaluation of the known historical cases of tailings dam failure was carried out. A corpus of 147 cases of worldwide tailings dam disasters, from which 26 located in Europe, was compiled in a database. This contains six sections, including dam location, its physical and constructive characteristics, actual and putative failure cause, sludge hydrodynamics, socio-economical consequences and

M. Rico; G. Benito; A. R. Salgueiro; A. D ´ õez-Herrero; H. G. Pereira

2008-01-01

75

Novel non-Mendelian determinant involved in the control of translation accuracy in Saccharomyces cerevisiae.  

PubMed Central

Two cytoplasmically inherited determinants related by their manifestation to the control of translation accuracy were previously described in yeast. Cells carrying one of them, [PSI(+)], display a nonsense suppressor phenotype and contain a prion form of the Sup35 protein. Another element, [PIN(+)], determines the probability of de novo generation of [PSI(+)] and results from a prion form of several proteins, which can be functionally unrelated to Sup35p. Here we describe a novel nonchromosomal determinant related to the SUP35 gene. This determinant, designated [ISP(+)], was identified as an antisuppressor of certain sup35 mutations. We observed its loss upon growth on guanidine hydrochloride and subsequent spontaneous reappearance with high frequency. The reversible curability of [ISP(+)] resembles the behavior of yeast prions. However, in contrast to known prions, [ISP(+)] does not depend on the chaperone protein Hsp104. Though manifestation of both [ISP(+)] and [PSI(+)] is related to the SUP35 gene, the maintenance of [ISP(+)] does not depend on the prionogenic N-terminal domain of Sup35p and Sup35p is not aggregated in [ISP(+)] cells, thus ruling out the possibility that [ISP(+)] is a specific form of [PSI(+)]. We hypothesize that [ISP(+)] is a novel prion involved in the control of translation accuracy in yeast.

Volkov, Kirill V; Aksenova, Anna Yu; Soom, Malle J; Osipov, Kirill V; Svitin, Anton V; Kurischko, Cornelia; Shkundina, Irina S; Ter-Avanesyan, Michael D; Inge-Vechtomov, Sergey G; Mironova, Ludmila N

2002-01-01

76

Human tails and pseudotails.  

PubMed

A case of a tail in a 2-week-old infant is reported, and findings from a review of 33 previously reported cases of true tails and pseudotails are summarized. The true, or persistent, vestigial tail of humans arises from the most distal remnant of the embryonic tail. It contains adipose and connective tissue, central bundles of striated muscle, blood vessels, and nerves and is covered by skin. Bone, cartilage, notochord, and spinal cord are lacking. The true tail arises by retention of structures found normally in fetal development. It may be as long as 13 cm, can move and contract, and occurs twice as often in males as in females. A true tail is easily removed surgically, without residual effects. It is rarely familial. Pseudotails are varied lesions having in common a lumbosacral protrusion and a superficial resemblance to persistent vestigial tails. The most frequent cause of a pseudotail in a series of ten cases obtained from the literature was an anomalous prolongation of the coccygeal vertebrae. Additional lesions included two lipomas, and one each of teratoma, chondromegaly , glioma, and a thin, elongated parasitic fetus. PMID:6373560

Dao, A H; Netsky, M G

1984-05-01

77

The Tail of BPM  

NASA Astrophysics Data System (ADS)

Business process management suites (BPMS's) represent one of the fastest growing segments in the software industry as organizations automate their key business processes. As this market matures, it is interesting to compare it to Chris Anderson's 'Long Tail.' Although the 2004 "Long Tail" article in Wired magazine was primarily about the media and entertainment industries, it has since been applied (and perhaps misapplied) to other markets. Analysts describe a "Tail of BPM" market that is, perhaps, several times larger than the traditional BPMS product market. This paper will draw comparisons between the concepts in Anderson's article (and subsequent book) and the BPM solutions market.

Kruba, Steve; Meyer, Jim

78

Genetic Evidence That the Ovo Locus Is Involved in Drosophila Germ Line Sex Determination  

PubMed Central

Zygotically contributed ovo gene product is required for the survival of female germ cells in Drosophila melanogaster. Trans-allelic combinations of weak and dominant ovo mutations (ovo(D)) result in viable germ cells that appear to be partially transformed from female to male sexual identity. The ovo(D2) mutation is partially suppressed by many Sex-lethal alleles that affect the soma, while those that affect only the germ line fail to interact with ovo(D2). One of two loss-of-function ovo alleles is suppressed by a loss-of-function Sex-lethal allele. Because ovo mutations are germ line dependent, it is likely that ovo is suppressed by way of communication between the somatic and germ lines. A loss-of-function allele of ovo is epistatic to germ line dependent mutations in Sex-lethal. The germ line dependent sex determination mutation, sans fille, and ovo(D) mutations show a dominant synergistic interaction resulting in partial transformation of germ line sexual identity. The ovo locus appears to be involved in germ line sex determination and is linked in some manner to sex determination in the soma.

Oliver, B.; Pauli, D.; Mahowald, A. P.

1990-01-01

79

Active and Accurate trans-Translation Requires Distinct Determinants in the C-terminal Tail of SmpB Protein and the mRNA-like Domain of Transfer Messenger RNA (tmRNA).  

PubMed

Unproductive ribosome stalling in eubacteria is resolved by the actions of SmpB protein and transfer messenger (tm) RNA. We examined the functional significance of conserved regions of SmpB and tmRNA to the trans-translation process. Our investigations reveal that the N-terminal 20 residues of SmpB, which are located near the ribosomal decoding center, are dispensable for all known SmpB activities. In contrast, a set of conserved residues that reside at the junction between the tmRNA-binding core and the C-terminal tail of SmpB play an important role in tmRNA accommodation. Our data suggest that the highly conserved glycine 132 acts as a flexible hinge that enables movement of the C-terminal tail, thus permitting proper positioning and establishment of the tmRNA open reading frame (ORF) as the surrogate template. To gain further insights into the function of the SmpB C-terminal tail, we examined the tagging activity of hybrid variants of tmRNA and the SmpB protein, in which the tmRNA ORF or the SmpB C-terminal tail was substituted with the equivalent but highly divergent sequences from Francisella tularensis. We observed that the hybrid tmRNA was active but resulted in less accurate selection of the resume codon. Cognate hybrid SmpB was necessary to restore activity. Furthermore, accurate tagging was observed when the identity of the resume codon was reverted from GGC to GCA. Taken together, these data suggest that the engagement of the tmRNA ORF and the selection of the correct translation resumption point are distinct activities that are influenced by independent tmRNA and SmpB determinants. PMID:23986442

Camenares, Devin; Dulebohn, Daniel P; Svetlanov, Anton; Karzai, A Wali

2013-08-28

80

Characteristics of live animal allometric measurements associated with body fat in fat-tailed sheep  

Microsoft Academic Search

Body weight (LW), condition score (BCS), tail length on inner side of tail (TL), tail volume measured by water displacement (TV) and tail circumference (TC), width (TW) as well as thickness at the base (TT) were measured in live Menz (n=303) and Horro (n=151) sheep to determine their possible use in breeding programmes aimed at improving ability to deposit fat

Ewnetu Ermias; J. E. O. Rege

2003-01-01

81

Selective tryptophan determination using tryptophan oxidases involved in bis-indole antibiotic biosynthesis.  

PubMed

A novel tryptophan assay was developed using tryptophan oxidases. Although many l-amino acid oxidases (LAAOs) have been reported to catalyze tryptophan oxidation, most of them have broad substrate specificity and oxidize multiple amino acids besides tryptophan. To obtain a tryptophan-specific LAAO, we focused on bis-indole antibiotic biosynthesis, a bacterial secondary metabolic pathway. A putative LAAO from Streptomyces sp. TP-A0274, StaO involved in staurosporine biosynthesis, was heterologously expressed, biochemically characterized, and shown to serve as a selective tryptophan oxidase for the first time. In addition, another LAAO, VioA involved in violacein biosynthesis in Chromobacterium violaceum, was characterized for comparison with StaO. Interestingly, StaO and VioA share similar properties, namely narrow substrate specificity and high affinity for l-tryptophan, despite the phylogenetic distance between these enzymes. Owing to these features, uncommon among known LAAOs, StaO and VioA assays can be used for selective and accurate quantification of l-tryptophan via a coupled colorimetric reaction. Indeed, StaO and VioA assays provided tryptophan concentrations in human plasma as accurately as those obtained by high-performance liquid chromatography. Therefore, these enzymes were clearly shown to offer an effective method for determining tryptophan in biological samples rapidly, inexpensively, and accurately. The results shown here also suggest the possibility of metabolism-oriented screening as a strategy to obtain enzymes highly selective for individual biomolecules. PMID:23545192

Kameya, Masafumi; Onaka, Hiroyasu; Asano, Yasuhisa

2013-03-29

82

A mass spectrometric method to determine activities of enzymes involved in polyamine catabolism.  

PubMed

An analytical method for the determination of three polyamines (putrescine, spermidine, and spermine) and five acetylpolyamines [N(1)-acetylspermidine (N(1)AcSpd), N(8)-acetylspermidine (N(8)AcSpd), N(1)-acetylspermine, N(1),N(8)-diacetylspermidine, and N(1),N(12)-diacetylspermine] involved in the polyamine catabolic pathway has been developed using a hybrid tandem mass spectrometer. Heptafluorobutyryl (HFB) derivatives of these compounds and respective internal standards labeled with stable isotopes were analyzed simultaneously by TOF MS, based on peak areas appearing at appropriate m/z values. The isomers, N(1)AcSpd and N(8)AcSpd were determined from their fragment ions, the acetylamidopropyl and acetylamidobutyl groups, respectively, using MS/MS with (13)C(2)-N(1)AcSpd and (13)C(2)-N(8)AcSpd which have the (13)C(2)-acetyl group as an internal standard. The TOF MS method was successfully applied to measure the activity of enzymes involved in polyamine catabolic pathways, namely N(1)-acetylpolyamine oxidase (APAO), spermine oxidase (SMO), and spermidine/spermine N(1)-acetyltransferase (SSAT). The following natural substrates and products labeled with stable isotopes considering the application to biological samples were identified; for APAO, [4,9,12-(15)N(3)]-N(1)-acetylspermine and [1,4,8-(15)N(3)]spermidine ((15)N(3)-Spd), respectively; for SMO, [1,4,8,12-(15)N(4)]spermine and (15)N(3)-Spd, respectively; and for SSAT, (15)N(3)-Spd and [1,4,8-(15)N(3)]-N(1)-acetylspermidine, respectively. PMID:23021806

Moriya, Shunsuke; Iwasaki, Kaori; Samejima, Keijiro; Takao, Koichi; Kohda, Kohfuku; Hiramatsu, Kyoko; Kawakita, Masao

2012-08-28

83

Phytoremediation of mine tailings in temperate and arid environments  

Microsoft Academic Search

Phytoremediation is an emerging technology for the remediation of mine tailings, a global problem for which conventional remediation\\u000a technologies are costly. There are two approaches to phytoremediation of mine tailings, phytoextraction and phytostabilization.\\u000a Phytoextraction involves translocation of heavy metals from mine tailings to the plant shoot biomass followed by plant harvest,\\u000a while phytostabilization focuses on establishing a vegetative cap that

Monica O. Mendez; Raina M. Maier

2008-01-01

84

An alternative method to determine the 5' extremities of non-segmented, negative sense RNA viral genomes using positive replication intermediate 3' tailing: application to two members of the Paramyxoviridae family.  

PubMed

Determining the sequence of non-segmented, negative sense RNA viral genomes is far from routine and often requires the application of several techniques. In this study, an existing method used currently just for determination of the genomic 3' extremity was used to determine both the 3' and 5' sequence extremities of a Newcastle disease virus and an avian metapneumovirus. This was achieved with a single 3' nucleotide tailing reaction of both the genomic RNA and the full length, positive sense, antigenomic RNA, followed by a single reverse transcription reaction targeted to the common polynucleotide tails, and then individual PCRs specific for each extremity using PCR primers derived from the sequence of the RT primer or from neighbouring virus sequences known previously. For each virus the method was employed separately. Sequences from both viruses were in agreement with those reported previously for other paramyxoviruses, yet one extra base at the 3' and one extra base at the 5' were identified for the avian metapneumovirus. In this study, importantly, the newly determined extremities maintained the complementarity known to exist between the extremities of these viruses. The method was equally successful with both viruses and can be tailored easily to function with other non-segmented, negative sense viruses through minor modification of only the primer sequences. PMID:23707921

Brown, Paul A; Briand, Francois-Xavier; Guionie, Olivier; Lemaitre, Evelyne; Courtillon, Celine; Henry, Aurelie; Jestin, Véronique; Eterradossi, Nicolas

2013-05-23

85

The amino-terminal tails of the core histones and the translational position of the TATA box determine TBP/TFIIA association with nucleosomal DNA.  

PubMed Central

We establish that the TATA binding protein (TBP) in the presence of TFIIA recognizes the TATA box in nucleosomal DNA dependent on the dissociation of the amino-terminal tails of the core histones from the nucleosome and the position of the TATA box within the nucleosome. We examine TBP/TFIIA access to the TATA box with this sequence placed in four distinct rotational frames with reference to the histone surface and at three distinct translational positions at the edge, side and dyad axis of the nucleosome. Under our experimental conditions, we find that the preferential translational position at which TBP/TFIIA can bind the TATA box is within linker DNA at the edge of the nucleosome and that binding is facilitated if contacts made by the amino-terminal tails of the histones with nucleosomal DNA are eliminated. TBP/TFIIA binding to DNA at the edge of the nucleosome occurs with the TATA box in all four rotational positions. This is indicative of TBP/TFIIA association directing the dissociation of the TATA box from the surface of the histone octamer. Images

Godde, J S; Nakatani, Y; Wolffe, A P

1995-01-01

86

Survey of Parents in a Predominately Latino Elementary School to Determine Factors that Affect Parental Involvement  

ERIC Educational Resources Information Center

Present research has shown that parental involvement has a large effect on student achievement. The current study utilized both casual-comparative and correlation methodology and identified variables that influence parental involvement. A review of literature with respect to parental involvement was presented. The study utilized survey data from…

Bodenstab, Tracy

2012-01-01

87

Uranium mill tailings stabilization  

SciTech Connect

Uranium mill tailings pose a potential radiation health hazard to the public. Therefore, stabilization or disposal of these tailings in a safe and environmentally sound way is needed to minimize radon exhalation and other environmental hazards. One of the most promising concepts for stabilizing U tailings is the use of asphalt emulsion to contain radon and other hazardous materials within uranium tailings. This approach is being investigated at the Pacific Northwest Laboratory. Results of these studies indicate that a radon flux reduction of greater than 99% can be obtained using either a poured-on/sprayed-on seal (3.0 to 7.0 mm thick) or an admixture seal (2.5 to 12.7 cm thick) containing about 18 wt % residual asphalt. A field test was carried out in June 1979 at the Grand Junction tailings pile in order to demonstrate the sealing process. A reduction in radon flux ranging from 4.5 to greater than 99% (76% average) was achieved using a 15.2-cm (6-in.) admix seal with a sprayed-on top coat. A hydrostatic stabilizer was used to apply the admix. Following compaction, a spray coat seal was applied over the admix as the final step in construction of a radon seal. Overburden was applied to provide a protective soil layer over the seal. Included in part of the overburden was a herbicide to prevent root penetration.

Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

1980-02-01

88

Evidence that apoptotic signalling in hypertrophic cardiomyocytes is determined by mitochondrial pathways involving protein kinase C?.  

PubMed

1. Cardiomyocyte apoptosis plays an important role in the transition from cardiac hypertrophy to heart failure. Hyper-trophic cardiomyocytes show an increased susceptibility to apoptotic stimuli, but the mechanisms remain unclear. 2. We hypothesized that activated protein kinase C? (PKC?) associated with cardiomyocyte hypertrophy could move from the cytoplasm to mitochondria, and subsequently trigger the apoptotic signalling pathway. 3. Hypertrophy was induced in cultured neonatal rat cardiomyocytes using endothelin-1 (ET-1), insulin-like growth factor-1 (IGF-1), thyroid hormone (T(3) ) or angiotensin-II (AngII). AngII at high concentrations (1 and 10 nmol/L) also induced apoptosis. Hypertrophic cells were then treated with AngII with or without specific inhibitors of the angiotensin receptors AT(1) and AT(2) (losartan and PD123319, respectively), endothelin receptor A (BQ-123) and PKC? (rottlerin). ET-1 plus AngII had a threefold and significant increase in apoptosis in the hypertrophic cultures compared with AngII alone. In association with the increase in apoptosis, this treatment also promoted mitochondrial translocation of PKC?, and increased expression of cleaved caspase 9 and activity of caspase 3. All of these increases were modulated by concurrent use of the PKC? inhibitor, rottlerin. 4. The results suggest that apoptotic signalling in hypertrophic cardiomyocytes is determined by mitochondrial pathways involving PKC?. PMID:20880184

Xie, Man-Jiang; Chang, Hui; Wang, Yun-Ying; Zhang, Lin; Song, Zhen; Guo, Wan-Gang; Wang, Tao; Che, Hong-Lei; Yu, Zhi-Bin

2010-12-01

89

Data driven rank tests for classes of tail alternatives  

Microsoft Academic Search

Tail alternatives describe the frequent occurrence of a non-constant shift in the two-sample problem with a shift function increasing in the tail. The classes of shift functions can be built up using Legendre polynomials. It is important to rightly choose the number of polynomials involved. Here this choice is based on the data, using a modification of Schwarz's selection rule.

Willem Albers; Wilbert C. M. Kallenberg; Felix Martini

1999-01-01

90

Neon-20, oxygen-16, and helium-4 densities, temperatures, and suprathermal tails in the solar wind determined with WIND/MASS  

NASA Astrophysics Data System (ADS)

Measurements from the MASS instrument on the WIND spacecraft from late Dec. 94 through Aug. 95 are reported for 20Ne, 16O, and 4He. The average 4He/20Ne density ratio is 566±87 with considerable variability. The average 16O/20Ne density ratio is 8.0±0.6 and is independent, within experimental uncertainty, of solar wind speed. The 20Ne/4He and 16O/4He temperature ratios at the lowest solar wind speeds are consistent with unity, increasing with increasing speed to values exceeding that expected from mass proportionality. 20Ne, 16O, and 4He distribution functions exhibit high energy tails which are well-fit by a kappa function.

Collier, Michael R.; Hamilton, D. C.; Gloeckler, G.; Bochsler, P.; Sheldon, R. B.

91

Responses to Tail Docking in Calves and Heifers  

Microsoft Academic Search

The primary objective of this study was to determine the behavioral and physiological effects of tail banding and atrophy using rubber rings 2 to 4 mo before first parturition in dairy heifers either with or without the use of epidural anesthesia. The secondary objective was to determine behavioral responses to tail banding using rubber rings in calves 7 to 42

D. A. Schreiner; P. L. Ruegg

2002-01-01

92

Myosin5a Tail Associates Directly with Rab3A-containing Compartments in Neurons*  

PubMed Central

Myosin-Va (Myo5a) is a motor protein associated with synaptic vesicles (SVs) but the mechanism by which it interacts has not yet been identified. A potential class of binding partners are Rab GTPases and Rab3A is known to associate with SVs and is involved in SV trafficking. We performed experiments to determine whether Rab3A interacts with Myo5a and whether it is required for transport of neuronal vesicles. In vitro motility assays performed with axoplasm from the squid giant axon showed a requirement for a Rab GTPase in Myo5a-dependent vesicle transport. Furthermore, mouse recombinant Myo5a tail revealed that it associated with Rab3A in rat brain synaptosomal preparations in vitro and the association was confirmed by immunofluorescence imaging of primary neurons isolated from the frontal cortex of mouse brains. Synaptosomal Rab3A was retained on recombinant GST-tagged Myo5a tail affinity columns in a GTP-dependent manner. Finally, the direct interaction of Myo5a and Rab3A was determined by sedimentation velocity analytical ultracentrifugation using recombinant mouse Myo5a tail and human Rab3A. When both proteins were incubated in the presence of 1 mm GTP?S, Myo5a tail and Rab3A formed a complex and a direct interaction was observed. Further analysis revealed that GTP-bound Rab3A interacts with both the monomeric and dimeric species of the Myo5a tail. However, the interaction between Myo5a tail and nucleotide-free Rab3A did not occur. Thus, our results show that Myo5a and Rab3A are direct binding partners and interact on SVs and that the Myo5a/Rab3A complex is involved in transport of neuronal vesicles.

Wollert, Torsten; Patel, Anamika; Lee, Ying-Lung; Provance, D. William; Vought, Valarie E.; Cosgrove, Michael S.; Mercer, John A.; Langford, George M.

2011-01-01

93

Happy Tailings to You  

NSDL National Science Digital Library

In this activity, students prepare a sample of "mine tailings", then separate out desirable materials using whatever method they choose, and quantify the results. They will discover that sometimes it's hard to separate desirable minerals from undesirable ones, especially if they look alike or the crystals are of similar sizes. Students learn that old, worked-out mines contain some desirable minerals (in small quantities) mixed in with unwanted minerals, but that doesn't stop some people from trying to squeeze out the last drop. Once considered tailings (or trash), the mix may now be profitable for mining. Desirable minerals can be separated physically and chemically.

94

Human tail: nature's aberration.  

PubMed

Human tail refers to a congenital cutaneous appendix protruding from the lumbosacral region. It is usually associated with an underlying spina bifida occulta, a form of spinal dysraphism. A contiguous fibrolipoma can sometimes be seen extending from the subcutaneous portion of the tail into the inferior spinal cord, resulting in tethered cord syndrome. Management of such lesions includes complete neurologic examination and magnetic resonance imaging. Early diagnosis and microsurgical intervention can prevent development or progression of severe neurologic defects in later life. PMID:22241711

Kumar, Dipti; Kapoor, Akshay

2012-01-12

95

Determinants of muscle metaboreflex and involvement of baroreflex in boys and young men.  

PubMed

This study aimed to assess the arterial pressure (AP) determinants during the muscle metaboreflex in boys and men and to investigate the contribution of baroreflex and sympathovagal function to the metaboreflex-induced responses. Fourteen pre-adolescent boys and 13 men performed a protocol involving: baseline, isometric handgrip exercise, circulatory occlusion, and recovery. The same protocol was repeated without occlusion. During baseline, boys had lower beat-to-beat AP, higher heart rate (HR), and lower low/high frequency HR variability. During exercise, a parasympathetic withdrawal was evident in both groups. In adults, HR was the key contributor to the pressure response, with no changes in stroke volume, whereas in boys, the lower HR increase was counterbalanced by an increase in stroke volume, resulting in similar relative increases in AP in both groups. In recovery, boys exhibited a faster rate of HR-decay, rapid vagal reactivation, and greater decrease in TPR than men. An overshoot in baroreceptor sensitivity was observed in men. The isolated metaboreflex resulted in a similar AP elevation in both age groups (by ~15 mmHg), and attenuated spontaneous baroreceptor sensitivity. However, during the metaboreflex, pre-adolescent males exhibited a lower increase in peripheral resistance and a greater bradycardic response than adults, and a fast restoration of vagal activity to non-occlusion levels. During metaboreflex, boys were capable of eliciting a pressure response similar to the one elicited by men; however, the interplay of the mechanisms underlying the rise in AP differed between the two groups with the vagal contribution being greater in the younger participants. PMID:22983569

Dipla, Konstantina; Papadopoulos, Stavros; Zafeiridis, Andreas; Kyparos, Antonios; Nikolaidis, Michalis G; Vrabas, Ioannis S

2012-09-15

96

Containment systems for uranium-mill tailings  

SciTech Connect

Cover and liner systems for uranium mill tailings in the United States must satisfy stringent requirements regarding long-term stability, radon control, and radionuclide and hazardous chemical migration. The cover and liner technology discussed in this paper involves: (1) single and multilayer earthen cover systems; (2) asphalt emulsion radon barrier systems; and (3) asphalt, clay, and synthetic liner systems. These systems have been field tested at the Grand Junction, Colorado, tailings pile, where they have been shown to effectively reduce radon releases and radionuclide and chemical migration.

Hartley, J.N.; Buelt, J.L.

1982-11-01

97

Student separateness–connectedness as a determinant of acceptable faculty involvement in students' social networks  

Microsoft Academic Search

A number of digital platforms have been in use for educational purposes in universities, but studies have shown little use of social networking platforms for educational purposes, despite indications of heavy student involvement in them (Roblyer, McDaniel, Webb, Herman, & Witty, 2010). This study examines the views of students towards social networking in general, and towards professors' involvement in social

Patricia Nemetz; Kirk Damon Aiken; Vance Cooney; Vince Pascal

98

Acetyl-L-carnitine suppresses thyroid hormone-induced and spontaneous anuran tadpole tail shortening.  

PubMed

Mitochondrial membrane permeability transition (MPT) plays a crucial role in apoptotic tail shortening during anuran metamorphosis. L-carnitine is known to shuttle free fatty acids (FFAs) from the cytosol into mitochondria matrix for ?-oxidation and energy production, and in a previous study we found that treatment with L-carnitine suppresses 3, 3', 5-triiodothyronine (T3 ) and FFA-induced MPT by reducing the level of FFAs. In the present study we focus on acetyl-L-carnitine, which is also involved in fatty acid oxidation, to determine its effect on T3 -induced tail regression in Rana rugosa tadpoles and spontaneous tail regression in Xenopus laevis tadpoles. The ladder-like DNA profile and increases in caspase-3 and caspase-9 indicative of apoptosis in the tails of T3 -treated tadpoles were found to be suppressed by the addition of acetyl-L-carnitine. Likewise, acetyl-L-carnitine was found to inhibit thyroid hormone regulated spontaneous metamorphosis in X. laevis tadpoles, accompanied by decreases in caspase and phospholipase A2 activity, as well as non-ladder-like DNA profiles. These findings support our previous conclusion that elevated levels of FFAs initiate MPT and activate the signaling pathway controlling apoptotic cell death in tadpole tails during anuran metamorphosis. PMID:23489246

Hanada, Hideki; Kobuchi, Hirotsugu; Yamamoto, Masanao; Kashiwagi, Keiko; Katsu, Kenjiro; Utsumi, Toshihiko; Kashiwagi, Akihiko; Sasaki, Junzo; Inoue, Masayasu; Utsumi, Kozo

2013-02-20

99

"Tails" of Linguistic Survival  

ERIC Educational Resources Information Center

|Given the relatively short history of computerized corpora of spoken language, it is not surprising that few diachronic studies have been done on the grammatical features recently highlighted by the analysis of such corpora. This article, however, does take a diachronic perspective on one such feature: the syntactic feature of "tails" (Dik 1978).…

Timmis, Ivor

2010-01-01

100

Dolphin Skeleton - Tail  

NSDL National Science Digital Library

The dolphin is built to be sleek. Its body is made of almost entirely backbone (a gliding joint) which makes it very flexible under water. The ribs protect the inner organs of the dolphin and the tail beats from side to side, thrusting the animal forward.

Ketan Patel (California State University, Fullerton;Student, Biological Sciences)

2007-07-14

101

Crocodile Skeleton - Tail  

NSDL National Science Digital Library

The crocodile is a reptile that has a long and narrow skeleton. The backbone (a gliding joint) of this animal extends into a powerful tail, allowing it to swim through water. The ribs of the crocodile are small and serve to protect its inner organs.

Ketan Patel (California State University, Fullerton;Student, Biological Science)

2007-07-14

102

Internal Lifschitz tails  

NASA Astrophysics Data System (ADS)

We consider an Anderson model in v dimensions with a potential distribution supported in ( a, b)?( c, d), where c- b>4v. We prove the existence of Lifschitz tails at the edges of the internal gap at b+2v and c- 2v. This reproves results of Mezincescu.

Simon, Barry

1987-03-01

103

REAR PROFILE OF TAIL FROM SECOND LEVEL OF TAIL DOCK ...  

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

REAR PROFILE OF TAIL FROM SECOND LEVEL OF TAIL DOCK STAND, SHOWING AIRCRAFT NUMBER (319), HORIZONTAL STABILIZER, TAIL CONE AND COOLING CTS FOR THE AUXILIARY POWER UNIT (APU), MECHANIC PAUL RIDEOUT IS LOWERING THE BALANCE PANELS ON THE STABILIZERS FOR LUBRICATION AND INSPECTION. - Greater Buffalo International Airport, Maintenance Hangar, Buffalo, Erie County, NY

104

Tissue-Specific Expression of Head-to-Tail Cyclized Miniproteins in Violaceae and Structure Determination of the Root Cyclotide Viola hederacea root cyclotide1W?  

PubMed Central

The plant cyclotides are a family of 28 to 37 amino acid miniproteins characterized by their head-to-tail cyclized peptide backbone and six absolutely conserved Cys residues arranged in a cystine knot motif: two disulfide bonds and the connecting backbone segments form a loop that is penetrated by the third disulfide bond. This knotted disulfide arrangement, together with the cyclic peptide backbone, renders the cyclotides extremely stable against enzymatic digest as well as thermal degradation, making them interesting targets for both pharmaceutical and agrochemical applications. We have examined the expression patterns of these fascinating peptides in various Viola species (Violaceae). All tissue types examined contained complex mixtures of cyclotides, with individual profiles differing significantly. We provide evidence for at least 57 novel cyclotides present in a single Viola species (Viola hederacea). Furthermore, we have isolated one cyclotide expressed only in underground parts of V. hederacea and characterized its primary and three-dimensional structure. We propose that cyclotides constitute a new family of plant defense peptides, which might constitute an even larger and, in their biological function, more diverse family than the well-known plant defensins.

Trabi, Manuela; Craik, David J.

2004-01-01

105

Critical Parameters for Tailings Embankments.  

National Technical Information Service (NTIS)

Geotechnical data on copper, uranium, and phosphate tailings from 41 mines were collected and analyzed to empirically establish the variability in strength properties for tailings embankments. These data were analyzed both from geotechnical and statistica...

G. B. Baecher J. S. Lin J. A. Consla W. A. Marr

1983-01-01

106

Long distance seed dispersal by wind: measuring and modelling the tail of the curve  

Microsoft Academic Search

The size and shape of the tail of the seed dispersal curve is important in determining the spatial dynamics of plants, but\\u000a is difficult to quantify. We devised an experimental protocol to measure long-distance dispersal which involved measuring\\u000a dispersal by wind from isolated individuals at a range of distances from the source, but maintaining a large and constant\\u000a sampling intensity

James M. Bullock; Ralph T. Clarke

2000-01-01

107

Heavy tails and currency crises  

Microsoft Academic Search

In affine models of foreign exchange rate returns, the nature of cross sectional interdependence in crisis periods hinges on the tail properties of the fundamentals' distribution. If the fundamentals exhibit thin tails like the normal distribution, the dependence vanishes asymptotically; while the dependence remains in the case of heavy tailed fundamentals as in case of the Student-t distribution. The linearity

P. Hartmann; S. Straetmans; C. G. de Vries

2010-01-01

108

Genetic and molecular analysis of fox-1, a numerator element involved in Caenorhabditis elegans primary sex determination.  

PubMed Central

fox-1 was previously identified as a candidate numerator element based on its overexpression phenotype. FOX-1 is an RRM-type RNA-binding protein, which can bind RNAs in vitro. Western analysis detects FOX-1 throughout development. fox-1::lacZ comes on ubiquitously early during embryogenesis. Postembryonically, fox-1::lacZ is expressed sex specifically in a subset of cells in the head and tail. We describe a Tc1-derived deletion allele [fox-1(Delta)] that removes the RRM domain. fox-1(Delta) confers no phenotype in XXs, but can rescue XO-specific lethality and feminization caused by duplications of the left end of the X. fox-1(Delta) synergizes with putative numerators, resulting in abnormal XX development. Genetic analysis indicated that fox-1(Delta) leads to a slight increase in xol-1 activity, while fox-1(gf) leads to partial loss of xol-1 activity, and xol-1 is epistatic to fox-1. RNase protection experiments revealed increased levels of the 2.2-kb xol-1 message in fox-1(Delta) animals, and reduced levels in fox-1(gf) animals. Additionally, fox-1(Delta) impairs male mating efficiency, which, we propose, represents another function of fox-1, independent of xol-1 and its role in sex determination.

Skipper, M; Milne, C A; Hodgkin, J

1999-01-01

109

Ectoderm to Mesoderm Lineage Switching During Axolotl Tail Regeneration  

Microsoft Academic Search

Foreign environments may induce adult stem cells to switch lineages and populate multiple tissue types, but whether this mechanism is used for tissue repair remains uncertain. Urodele amphibians can regenerate fully functional, multitissue structures including the limb and tail. To determine whether lineage switching is an integral feature of this regeneration, we followed individual spinal cord cells live during tail

Karen Echeverri; Elly M. Tanaka

2002-01-01

110

8 CFR 1208.30 - Credible fear determinations involving stowaways and applicants for admission found inadmissible...  

Code of Federal Regulations, 2013 CFR

...and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEDURES FOR ASYLUM AND...credible fear determinations, and the immigration judges have exclusive...

2013-01-01

111

RhoA activation and actin reorganization involved in endothelial CAM-mediated endocytosis of anti-PECAM carriers: critical role for tyrosine 686 in the cytoplasmic tail of PECAM-1  

PubMed Central

Platelet-endothelial cell adhesion molecule-1 (PECAM-1), a transmembrane glycoprotein involved in leukocyte transmigration, represents a good target for endothelial drug delivery (eg, using antibody-directed nanocarriers, anti-PECAM/NCs). Although endothelial cells do not internalize PECAM antibodies, PECAM-1 engagement by multivalent anti-PECAM conjugates and nanocarriers causes endocytosis via a nonclassic CAM-mediated pathway. We found that endothelial uptake of multivalent anti-PECAM complexes is associated with PECAM-1 phosphorylation. Using model REN cells expressing a series of PECAM-1 deletion and point mutants, we found that the PECAM-1 cytoplasmic domain and, more precisely, PECAM-1 tyrosine 686, is critical in mediating RhoA activation and recruitment of EGFP-RhoA to anti-PECAM/NC binding sites at the plasmalemma, actin polymerization into phalloidin-positive stress fibers, and finally CAM endocytosis of anti-PECAM/NCs. Endothelial targeting and endocytosis of anti-PECAM/NCs were markedly efficient and did not compromise endothelial barrier function in vitro (determined by immunostaining of VE-cadherin and 125I-albumin transport across endothelial monolayers) or in vivo (determined by electron microscopy imaging of pulmonary capillaries and 125I-albumin transport from the blood into the lung tissue after intravenous injection of anti-PECAM/NCs in mice). These results reveal PECAM-1 signaling and interactions with the cytoskeleton, which are required for CAM-endocytosis, and may provide safe intra-endothelial drug delivery by anti-PECAM/NCs.

Garnacho, Carmen; Shuvaev, Vladimir; Thomas, Anu; McKenna, Lindsay; Sun, Jing; Koval, Michael; Albelda, Steven

2008-01-01

112

An Active Self-Determination Technique: Involving Students in Effective Career Planning.  

ERIC Educational Resources Information Center

|This paper discusses creating story boards to help students with disabilities to develop effective career plans. It describes storyboarding as a technique for project planning which requires active involvement of both hemispheres of the brain. A group of 6-8 people, including students, teachers, counselors, and vocational rehabilitation…

Denison, Grace L.

113

Mode of onset of psychosis and family involvement in help-seeking as determinants of duration of untreated psychosis  

Microsoft Academic Search

Background  The duration of untreated psychosis (DUP) is a potentially modifiable determinant of the early course of nonaffective psychotic\\u000a disorders, though a paucity of research has addressed determinants of DUP. Recent data from London and Nottingham, UK indicated\\u000a that a shorter DUP was predicted by: (1) an acute mode of onset, (2) employment, and (3) active involvement of at least one

Michael T. Compton; Victoria H. Chien; Amy S. Leiner; Sandra M. Goulding; Paul S. Weiss

2008-01-01

114

Determinants of male partner involvement in promoting deliveries by skilled attendants in Busia, Kenya.  

PubMed

A cross-sectional study covering 380 male partners and their spouses was conducted in Busia district in Western Kenya to establish demographic, socio-economic and cultural factors that affect male partner participation in promoting deliveries by skilled attendants. The study showed a significant relationship between level of education (P=0.0000) and level of income (P=0.0004) of the male partner and his support for skilled delivery. Lack of knowledge by male partners of complications associated with delivery, cultural beliefs, high fees charged for deliveries at health facilities and "un-cooperative" health workers are major contributing factors to low male partner involvement in child birth activities. Improving the levels of education and income of male partners, addressing the cultural beliefs and practices, improving health care provider-client relationship and sensitizing men on complications associated with pregnancy and child birth can contribute significantly in enhancing male partner involvement in promoting deliveries by skilled attendants. PMID:22980152

Nanjala, Mildred; Wamalwa, David

2012-02-29

115

Functional characterization of MADS box genes involved in the determination of oil palm flower structure  

Microsoft Academic Search

In order to study the molecular regulation of flower development in the monoecious species oil palm (Elaeis guineensis), cDNAs of 12 MADS box genes from this plant belonging to seven distinct subfamil- ies were previously isolated and characterized. Here studies carried out on five of these genes, each likely to be involved in floral morphogenesis: EgSQUA1 (SQUAMOSA subfamily); EgAGL2-1 (AGL2

Helene Adam; Stefan Jouannic; Yves Orieux; Fabienne Morcillo; Frederique Richaud; Yves Duval; James W. Tregear

2007-01-01

116

8 CFR 208.30 - Credible fear determinations involving stowaways and applicants for admission found inadmissible...  

Code of Federal Regulations, 2013 CFR

...procedures applicable to credible fear interviews, determinations, and reviews...officers conducting credible fear interviews shall have the authorities described in § 208.9(c). (d) Interview. The asylum officer, as...

2013-01-01

117

Student Perceptions of School Efforts to Facilitate Student Involvement, School Commitment, Self-Determination, and High School Graduation  

ERIC Educational Resources Information Center

This study examined the relationship between student perceptions of school efforts to facilitate student involvement, school commitment, self-determination skills, and on track indicators for graduation in 10th grade and actual graduation outcomes two years later. The participants were 154 primarily minority students in a large, urban school…

Cavendish, Wendy

2013-01-01

118

A rapid sensitive method for determining phospholipid phosphorus involving digestion with magnesium nitrate  

Microsoft Academic Search

A method is described for the rapid determination of phospholipid phosphorus in samples containing less than 0.5 ?g phosphorus.\\u000a Phospholipid phosphorus is first converted to inorganic phosphate by heating a dried lipid extract briefly over a Bunsen flame\\u000a in the presence of magnesium nitrate, then dissolving the resulting residue in dilute hydrochloric acid at 95 C. The determination\\u000a of the

Coral G. Duck-Chong

1979-01-01

119

Structural insight into recognition of methylated histone tails by retinoblastoma-binding protein 1.  

PubMed

Retinoblastoma-binding protein 1 (RBBP1), also named AT-rich interaction domain containing 4A (ARID4A), is a tumor and leukemia suppressor involved in epigenetic regulation in leukemia and Prader-Willi/Angelman syndromes. Although the involvement in epigenetic regulation is proposed to involve its chromobarrel and/or Tudor domains because of their potential binding to methylated histone tails, the structures of these domains and their interactions with methylated histone tails are still uncharacterized. In this work, we first found that RBBP1 contains five domains by bioinformatics analysis. Three of the five domains, i.e. chromobarrel, Tudor, and PWWP domains, are Royal Family domains, which potentially bind to methylated histone tails. We further purified these domains and characterized their interaction with methylated histone tails by NMR titration experiments. Among the three Royal Family domains, only the chromobarrel domain could recognize trimethylated H4K20 (with an affinity of ?3 mm), as well as recognizing trimethylated H3K9, H3K27, and H3K36 (with lower affinities). The affinity could be further enhanced up to 15-fold by the presence of DNA. The structure of the chromobarrel domain of RBBP1 determined by NMR spectroscopy has an aromatic cage. Mutagenesis analysis identified four aromatic residues of the cage as the key residues for methylated lysine recognition. Our studies indicate that the chromobarrel domain of RBBP1 is responsible for recognizing methylated histone tails in chromatin remodeling and epigenetic regulation, which presents a significant advance in our understanding of the mechanism and relationship between RBBP1-related gene suppression and epigenetic regulation. PMID:22247551

Gong, Weibin; Zhou, Tao; Mo, Jinjin; Perrett, Sarah; Wang, Jinfeng; Feng, Yingang

2012-01-12

120

Simulations of Instabilities in Tidal Tails  

NASA Astrophysics Data System (ADS)

We use graphics cards to run a hybrid test particle/N-body simulation to integrate 4 million massless particle trajectories within fully self-consistent N-body simulations of 128,000 - 256,000 particles. The number of massless particles allows us to resolve fine structure in the spatial distribution and phase space of a dwarf galaxy that is disrupted in the tidal field of a Milky Way type galaxy. The tidal tails exhibit clumping or a smoke-like appearance. By running simulations with different satellite particle mass, number of massive vs massless particles and with and without a galaxy disk, we have determined that the instabilities are not due to numerical noise or shocking as the satellite passes through the disk of the Galaxy. The instability is possibly a result of self-gravity which indicates it may be due to Jeans instabilities. Simulations involving different halo particle mass may suggest limitations on dark matter halo substructure. We find that the instabilities are visible in velocity space as well as real space and thus could be identified from velocity surveys as well as number counts.

Comparetta, Justin N.; Quillen, A. C.

2010-05-01

121

Determinants of Parental Authorization for Involvement of Newborn Infants in Clinical Trials  

Microsoft Academic Search

Objective. Parents have the right to de- cide on behalf of their infants whether to enroll them in controlled clinical trials. We determined the degree to which such parental decisions are influenced by risk and benefit considerations compared with other factors. Design. Cross-sectional survey. Participants. Parents who had recently given or de- clined consent to one of three controlled trials

John A. F. Zupancic; Pat Gillie; David L. Streiner; John L. Watts; Barbara Schmidt

2010-01-01

122

Structural Conservation of the Myoviridae Phage Tail Sheath Protein Fold  

SciTech Connect

Bacteriophage phiKZ is a giant phage that infects Pseudomonas aeruginosa, a human pathogen. The phiKZ virion consists of a 1450 {angstrom} diameter icosahedral head and a 2000 {angstrom}-long contractile tail. The structure of the whole virus was previously reported, showing that its tail organization in the extended state is similar to the well-studied Myovirus bacteriophage T4 tail. The crystal structure of a tail sheath protein fragment of phiKZ was determined to 2.4 {angstrom} resolution. Furthermore, crystal structures of two prophage tail sheath proteins were determined to 1.9 and 3.3 {angstrom} resolution. Despite low sequence identity between these proteins, all of these structures have a similar fold. The crystal structure of the phiKZ tail sheath protein has been fitted into cryo-electron-microscopy reconstructions of the extended tail sheath and of a polysheath. The structural rearrangement of the phiKZ tail sheath contraction was found to be similar to that of phage T4.

Aksyuk, Anastasia A.; Kurochkina, Lidia P.; Fokine, Andrei; Forouhar, Farhad; Mesyanzhinov, Vadim V.; Tong, Liang; Rossmann, Michael G. (SOIBC); (Purdue); (Columbia)

2012-02-21

123

The geomagnetic tail  

SciTech Connect

A review is presented of the plasma sheet and lobe regions of the magnetotail, focusing principally on large-scale processes or microprocesses with some large-scale effects. Consideration is given to quiet and average structures, not necessarily related to activity phases, with quasi-steady convection aspects, and with the characteristics of dynamic phases including acceleration mechanisms and single particle aspects. Attention is given to various activity models, average and quiet time properties, properties and effects of magnetospheric convection, dynamics of the magnetotail, and the near tail, substorm current wedge.

Birn, J. (USAF, Geophysics Laboratory, Hanscom AFB, MA (United States))

1991-01-01

124

Genetic Determinants Involved in the Susceptibility of Pseudomonas aeruginosa to ?-Lactam Antibiotics?  

PubMed Central

The resistome of P. aeruginosa for three ?-lactam antibiotics, namely, ceftazidime, imipenem, and meropenem, was deciphered by screening a comprehensive PA14 mutant library for mutants with increased or reduced susceptibility to these antimicrobials. Confirmation of the phenotypes of all selected mutants was performed by Etest. Of the total of 78 confirmed mutants, 41 demonstrated a reduced susceptibility phenotype and 37 a supersusceptibility (i.e., altered intrinsic resistance) phenotype, with 6 mutants demonstrating a mixed phenotype, depending on the antibiotic. Only three mutants demonstrated reduced (PA0908) or increased (glnK and ftsK) susceptibility to all three antibiotics. Overall, the mutant profiles of susceptibility suggested distinct mechanisms of action and resistance for the three antibiotics despite their similar structures. More detailed analysis indicated important roles for novel and known ?-lactamase regulatory genes, for genes with likely involvement in barrier function, and for a range of regulators of alginate biosynthesis.

Alvarez-Ortega, Carolina; Wiegand, Irith; Olivares, Jorge; Hancock, Robert E. W.; Martinez, Jose Luis

2010-01-01

125

Uranium mill tailings and radon  

SciTech Connect

The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the US may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action Program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

Hanchey, L.A.

1981-01-01

126

Uranium mill tailings and radon  

SciTech Connect

The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the United States may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

Hanchey, L.A.

1981-04-01

127

Two Gene Determinants Are Differentially Involved in the Biogenesis of Fap1 Precursors in Streptococcus parasanguis?  

PubMed Central

Mature Fap1, a 200-kDa fimbria-associated adhesin, is required for fimbrial biogenesis and biofilm formation in Streptococcus parasanguis. Fap1-like proteins are found in the genomes of many streptococcal and staphylococcal species. Fap1 is a serine-rich glycoprotein modified by O-linked glycan moieties. In this study, we identified a seven-gene cluster including secY2, orf1, orf2, orf3, secA2, gtf1, and gtf2 that is localized immediately downstream of fap1. The lower G+C contents and the presence of a putative transposase element suggest that this gene cluster was horizontally transferred from other bacteria and represents a genomic island. At least two genes in this island mediated Fap1 biogenesis. Mutation of a glucosyltransferase (Gtf1) gene led to accumulation of a Fap1 precursor, which had no detectable glycan moieties. Inactivation of a gene coding for an accessory Sec protein (SecY2) resulted in expression of a distinct Fap1 precursor, which reacted with one glycan-specific Fap1 antibody but not with another glycan-specific antibody. Furthermore, partially glycosylated Fap1 was detected on the cell surface and in the culture supernatant. These data suggest that SecY2 has a role in complete glycosylation of Fap1 and imply that SecY2 is not the only translocation channel for the Fap1 precursor and that alternative secretion machinery exists. Together, Gtf1 and SecY2 are involved in biogenesis of two distinct Fap1 precursors in S. parasanguis. Discovery of the effect of an accessory Sec protein on Fap1 glycosylation suggests that Fap1 secretion and glycosylation are coupled during Fap1 biogenesis.

Wu, Hui; Bu, Su; Newell, Peter; Chen, Qiang; Fives-Taylor, Paula

2007-01-01

128

Isoelectric points of some sulfonamides: determination by microelectrophoresis and by calculations involving acid-base strength.  

PubMed

The isoelectric points of four very slightly soluble sulfonamides were measured by microelectrophoresis of dilute suspensions as a function of pH. Ionic strength and pH were adjusted with KCl, KOH, and HCl only. The isoelectric points were also calculated from published values of acid and basic ionization constants which had been determined by potentiometric titration, and from changes in ultraviolet absorption spectra and in solubility as a function of pH. Including one sulfonamide whose isoelectric point as measured by microelectrophoresis was published, rather good agreement between the two methods was observed for all but one compound. All values were between 3.5 and 4.6, indicating that the sulfonamides function as weak acids rather than as amphoteric compounds at physiological pH. PMID:3225749

Schott, H; Astigarrabia, E

1988-11-01

129

Left-Right Determination: Involvement of Molecular Motor KIF3, Cilia, and Nodal Flow  

PubMed Central

Mammalian left–right determination is a good example for how multiple cell biological processes coordinate in the formation of a basic body plan. The leftward movement of fluid at the ventral node, called nodal flow, is the central process in symmetry breaking on the left–right axis. Nodal flow is autonomously generated by the rotation of posteriorly tilted cilia that are built by transport via KIF3 motor on cells of the ventral node. How nodal flow is interpreted to create left–right asymmetry has been a matter of debate. Recent evidence suggests that the leftward movement of sheathed lipidic particles, called nodal vesicular parcels (NVPs), may result in the activation of the noncanonical hedgehog signaling pathway, an asymmetric elevation in intracellular Ca2+ and changes in gene expression.

Hirokawa, Nobutaka; Tanaka, Yosuke; Okada, Yasushi

2009-01-01

130

Heavy-Tailed and Long-Tailed Distributions  

Microsoft Academic Search

\\u000a In this chapter we are interested in (right-) tail properties of distributions, i.e. in properties of a distribution which, for any x, depend only on the restriction of the distribution to (x,??). More generally it is helpful to consider tail properties of functions.

Sergey Foss; Dmitry Korshunov; Stan Zachary

131

3. VIEW OF WEST TAILING DAM, LARGE TANK, AND TAILING, ...  

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

3. VIEW OF WEST TAILING DAM, LARGE TANK, AND TAILING, LOOKING NORTHEAST. A SIX-FOOT SCALE IS LOCATED AGAINST WALL ON LEFT. PURPOSE OF TANK IS UNKNOWN, BUT APPEARS TO HAVE FALLEN FROM ITS ORIGINAL LOCATION AT THE MILL SITE, UP AND TO THE RIGHT OF THIS VIEW. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA

132

Risk factors for canine tail chasing behaviour in Japan.  

PubMed

The aim of this study was to investigate the risk factors for tail chasing behaviour that occurs when a dog spins in tight circles to chase its tail, sometimes biting it. The behaviour is a sign of canine compulsive disorder (CD). A questionnaire about tail chasing behaviour and general information about the animals was used to collect data on seven breeds of pet dogs. The data were gathered at a dog event and at veterinary practices. To determine which variables were associated with tail chasing behaviour, stepwise multiple regression analyses were performed. Regardless of cohort, 'breed' and 'source of acquisition' were significantly associated with tail chasing behaviour. Using a chi-square test, the association between 'source of acquisition' and the behaviour was examined separately in two breeds (Shiba inu and Dachshund) that had the largest number of individuals chasing their tails accompanied by biting and/or growling at them. This factor showed a significant and consistent association across the two breeds. With respect to the risk factors of 'breed' and 'source of acquisition', high percentages of Shiba inu and dogs originating from pet stores were included in the group chasing their tails with biting and/or growling. The results suggest that distinct risk factors exist for tail chasing behaviour and such factors appear to be regulated by both genetics and the environment. PMID:21993593

Goto, Akiko; Arata, Sayaka; Kiyokawa, Yasushi; Takeuchi, Yukari; Mori, Yuji

2011-10-10

133

Use of gold mill tailings in making bricks: a feasibility study.  

PubMed

Mill tailings dumps at Kolar Gold Fields, Karnataka, are creating environmental problems. One of the solutions to these problems is to use the mill tailings for some useful purpose. This study examined the possibility of making bricks from the mill tailings with some additives in laboratory experiments. Samples of the mill tailings and the additives were analysed for particle size distribution, Atterberg limits and specific gravity. The plasticity index of the mill tailings being zero, they could not be used directly for making bricks. Therefore some additives that had plasticity or binding properties were mixed with the mill tailings. Ordinary Portland cement, black cotton soils and red soils were selected as additives. Each of the additives was mixed separately with the mill tailings in different proportions by weight and a large number of bricks were prepared using metallic moulds. The bricks were termed as cement-tailings bricks or soil-tailings bricks, depending on the additives used. The cement-tailings bricks were cured for different periods and their corresponding compressive strengths were determined. The bricks with 20% of cement and 14 days of curing were found to be suitable. The soil-tailings bricks were sun-dried and then fired in a furnace at different temperatures. The quality of bricks was assessed in terms of linear shrinkage, water absorption and compressive strength. The cost analysis revealed that cement-tailings bricks would be uneconomical whereas the soil-tailings bricks would be very economical. PMID:17985673

Roy, Surendra; Adhikari, Govind R; Gupta, Rama N

2007-10-01

134

Migration of arsenic from old tailings ponds-A case study on the King Edward Mine, Cornwall, UK  

SciTech Connect

A methodology is presented to study the physico-chemical processes in old tailings ponds using an array of analytical-physical chemistry approaches. A case study was conducted on the sorption/desorption behaviour of arsenic in tailings pond 2406, at the King Edward Mine (KEM) in Cornwall, UK. The tailings pond was in operation from approximately 1907 to 1921. The methodology involves two principal stages: (1) sequential extraction followed by subsequent arsenic species determination to characterise the material with regards to the association of arsenic with soil phases and identification of As (III/V) in the easily accessible soil phase; (2) batch contacting/equilibrating the tailings pond material with As(III/V), followed by a similar procedure as in stage 1 to establish the material's As(III/V) phase distribution kinetics/thermodynamics. By extrapolating the data from present day samples we infer past and future elemental mobility. From this study it is concluded that adsorption and desorption from tailings material is a rapid process for the most unstable soil phases (non-specific and specific) and a slow process for the more stable phases (poorly crystalline and well crystalline). The hypothetical application of this conclusion to the tailings from dam 2406 is that, during the initial phases of the dam's creation (ca. 100 years ago), when arsenic was both in solution and bound to mineralogical components, arsenic must have dispersed into the environment as a result of slow As(V) adsorption/phase distribution processes. Aging of the tailings material sees the movement of the arsenic to the more stable soil phases, producing a situation that is seen at present day.

Beeston, Michael Philip [National Institute of Chemistry (Kiribati), Hajdrihova 19, SI-1001 Ljubljana (Slovenia); University of Exeter in Cornwall (UEC), Tremough Campus, TR10 9EZ Penryn, Cornwall (United Kingdom)], E-mail: Michael.Beeston@ki.si; Tuen van Elteren, Johannes [National Institute of Chemistry (Kiribati), Hajdrihova 19, SI-1001 Ljubljana (Slovenia); Slejkovec, Zdenka [Jozef Stefan Institute (JSI), Jamova 39, SI-1000 Ljubljana (Slovenia); Glass, Hylke Jan [University of Exeter in Cornwall (UEC), Tremough Campus, TR10 9EZ Penryn, Cornwall (United Kingdom)

2008-09-15

135

Economic evaluation of inactive uranium mill tailings, Old Rifle Site, Rifle, Colorado  

SciTech Connect

Mountain States Research and Development was contracted on March 1, 1981 to make an economic evaluation study at each of 12 abandoned uranium mill tailings sites in the western states. The objective of this work was to obtain the data necessary at each site to determine the possible revenue that could be derived from reprocessing the tailings. To accomplish this objective a drilling and sampling program was established for each site to determine the total amount of tailings and subbase material available for treatment and the amount of recoverable uranium, vanadium and molybdenum. These three metals were selected due to their common occurrence in uranium ores and common extractability in the leaching process. Laboratory leaching was then conducted on the samples obtained to determine the extractability of each of these metals and the optimum plant process to be applied. As the metal contents were generally low and represented mineral that had not been leached during previous processing, the economic evaluation is limited to consideration of the direct capital and operating costs required in connection with processing of each respective site material. Excavating, transportation and disposal of the material from each site in an environmentally acceptable location and manner was not within the scope of this project. It will be necessary to complete a separate study of these areas in order to determine the total costs involved. This report contains the results of the investigations of the Old Rifle Site.

Teel, J.H. [Mountain States Research and Development, Tucson, AZ (United States)

1982-12-01

136

Teratoma in Human Tail Lipoma  

Microsoft Academic Search

We report a case of a rare congenital teratoma that developed in a lipoma attached to a remnant human tail. A male newborn baby presented with a large, 3-cm mass with an open margin, which pedunculated from a tail attached to the midline skin of the coccygeal area. Magnetic resonance images demonstrated multiple sacral spinal bifida without cord tethering, and

Se-Hyuck Park; Jee Soon Huh; Ki Hong Cho; Yong Sam Shin; Se Hyck Kim; Young Hwan Ahn; Kyung Gi Cho; Soo Han Yoon

2005-01-01

137

Human tail with spina bifida.  

PubMed

A true human tail is a rare occurrence and is defined as a caudal, vestigial, midline protrusion with skin covering connective tissue, muscle, vessels and nerves. We report a case of true human tail in a child, which is a very rare happening in humans. PMID:19922280

Chauhan, S P S; Gopal, N N; Jain, Mohit; Gupta, Anurag

2009-12-01

138

Trends in Tailing Dam Safety  

Microsoft Academic Search

Recent releases of tailing effluents and solids from containment facilities around the world, including Mary Spruitt (1994), Omai (1995) and Marcopper (1996), have heightened awareness that risks associated with tailing containment must be fully addressed during all phases of a facility life. Recent studies by independent international organizations (United Nations Environment Programme (UNEP), 1996; United Stated Committee on Large Dams

Iain G. Bruce; Clint Logue; Lori-Ann Wilchek

139

Determination of a two-tailed 100(1-alpha)% upper limit on the relative error in the laboratory-to-laboratory standard deviation obtained from an interlaboratory study.  

PubMed

For some classes of analytical methods, it is assumed that the error in the laboratory-to-laboratory standard deviation (S(L)) is appreciable. To demonstrate the magnitude of this error in S(L) for such methods, formulas were derived to obtain a two-tailed 100(1-alpha)% upper limit on the relative error in S(L) obtained from an interlaboratory study, assuming that the laboratory-to-laboratory variance (S(L)2) obtained in the validation of an analytical method is approximately normal and/or Chi-square distributed. This 100(1-alpha)% upper limit (delta(1-alpha/2)) is referred to as a margin of relative error in S(L) (MRE(S(L. Monte Carlo simulations were performed, and the results compared satisfactorily with the formula calculations. To aid in designing future interlaboratory studies in which concern is focused on the magnitude of the uncertainty in S(L), expressed as a proportion of the true value (sigma L), a formula was derived to determine the number of laboratories needed to attain a given MRE in S(L) for a stated number of replicates per laboratory. PMID:19916398

McClure, Foster D; Lee, Jung K

140

Cluster Size Distribution and Relaxation Long Time Tails  

NASA Astrophysics Data System (ADS)

Relaxation phenomena such as the dielectric, magnetic and mechanical relaxation of many disordered physical systems exhibit universal features in particular for long time one often observes an exponential behavior known as long time tail relaxation. We show that if individual clusters in these materials have a relaxation time proportional to the cluster size, the existence of a stable probability size distribution with a long tail power law changes dramatically the relaxation rate, from an initial exponential relaxation to a long time tail t-?. In this case it is the morphology of the system which determines its kinetics.

Vasquez, Alexis; Sotolongo, Oscar; Brouers, Francois

1997-08-01

141

Congenital Sensorineural Deafness in Australian Stumpy-Tail Cattle Dogs Is an Autosomal Recessive Trait That Maps to CFA10  

Microsoft Academic Search

BackgroundCongenital sensorineural deafness is an inherited condition found in many dog breeds, including Australian Stumpy-tail Cattle Dogs (ASCD). This deafness is evident in young pups and may affect one ear (unilateral) or both ears (bilateral). The genetic locus\\/loci involved is unknown for all dog breeds. The aims of this study were to determine incidence, inheritance mechanism, and possible association of

Susan Sommerlad; Allan F. McRae; Brenda McDonald; Isobel Johnstone; Leigh Cuttell; Jennifer M. Seddon; Caroline A. OLeary

2010-01-01

142

[A case of human tail].  

PubMed

A human tail is a rare anatomical curiosity. A case of a human tail associated with lipomyelomeningocele is reported. The made subject was born, by breech delivery, at the 39th-week with a 3,008 g body weight. He was admitted to our hospital because of the presence of a human tail and subcutaneous mass in the midline lumbosacral region. The tail was about 7.5 cm in length and 2 cm in diameter. It was elastic and covered by normal skin. No systemic anomaly was found. Spina bifida below L5 was revealed, and no bony shadow was found on the plain X-ray film. CT scan showed a low density area in the spinal canal between L3 and lower sacral region that extended into the tail through the spina bifida. MRI also revealed intraspinal long T2 mass which was attached to the spinal cord and extended into the tail. Myelogram indicated intradural extramedullary mass below the L3 level. Surgical treatment was performed on the 3rd month of life with a diagnosis of a human tail with lipomyelomeningocele. At surgery, the tail was found to consist mainly of lipomatous tissue which extended subcutaneously and entered the spinal canal through the spina bifida. The tail and subcutaneous lipomatous tissue were totally excised. The capsule of subcutaneous lipomatous tissue was followed circumferentially down into the spinal canal, and found to be transformed to arachnoid membrane. Intradural lipomatous tissue was excised piece by piece, leaving only a small remnant attached to the conus medullaris to preserve sacral nerve root function.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2000165

Yamatani, K; Saitoh, T; Oi, M; Oka, N; Endoh, T; Takaku, A

1991-01-01

143

Interactions of tailings leachate with local liner materials found at Canonsburg, Pennsylvania.  

SciTech Connect

The mill tailings site at Canonsburg, Pennsylvania is the first mill site to receive remedial action under the Department of Energy's Uranium Mill Tailings Remedial Action Program. Part of this remedial action will require excavating the 53,500 m/sup 3/ (70,000 yd/sup 3/) of tailings on the site having a specific activity exceeding 100 pCi/g, and encapsulating these contaminated tailings in a clay-lined cell. As part of the remedial action effort, Pacific Northwest Laboratory has been studying the interactions of tailings and tailings leachate with locally occurring clays proposed for liner materials. These studies include physical and chemical characterization of amended and unamended local clays, chemical characterization of the tailings, column studies of tailings leached with deionized water, and column studies of clays contacted with tailings solutions to determine the attenuation properties of the proposed liner materials. Column studies of tailings leached with deionized water indicated that the Canonsburg tailings could represent a source of soluble radium-226 and uranium-238, several trace metals, cations, and the anions SO/sub 4/, NO/sub 3/, and Cl. Of these soluble contaminants, uranium-238, radium-226, the trace metals As and Mo, and the anions F and SO/sub 4/ were present at levels exceeding maximum concentration levels in the tailings leaching column effluents. However, local clays, both in amended and unamended form were effective in attenuating contaminant migration. The soil amendments tested failed to increase radium attenuation. The tailings leaching studies indicated that the tailings will produce leachates of neutral pH and relatively low contaminant levels for at least 200 years. We believe that compacting the tailings within the encapsulation cell will help to reduce leaching of contaminants from the liner system, since very low permeabilities (<10/sup -8/ cm/s) were observed for even slightly compacted tailings materials.

Dodson, M.E.; Gee, G.W.; Serne, R.J.

1984-04-01

144

Dust tail of the distant comet C/1999 J2 (Skiff)  

NASA Astrophysics Data System (ADS)

CCD observations of comet C/1999 J2 (Skiff) were made at the Pik Terskol Observatory on September 15, 1999. The 2-m telescope equipped with the two-channel focal reducer of the Max-Plank-Institute for Aeronomy was used to study the cometary environment. In spite of the large heliocentric distance, 7.24 AU, a straight dust tail with fairly well defined boundaries was recorded. These data provide an opportunity to study the peculiarity of dust, that is not driven by water vapor. To fit the dust tail, a Monte Carlo model was developed. We trace the trajectories of about 107 sample grains to construct the detailed brightness distribution in the comet tail. The simulated isophote field and the observed one agree very well. In our model we also take into account the heliocentric dependence of the dust production rate and ejection velocity, and the dust ejection anisotropy. To transform the particle population to brightness in the modelled tail we calculate the scattering cross section of a separate particle using Mie theory. The age, ejection velocity, dust size distribution, minimum and maximum size of the involved dust particles have been derived from the model giving the best fit. The intensity map is in agreement with a flow of the slowly travelling icy grains. It has been determined that the age of the dust tail of comet C/1999 J2 (Skiff) was, at the moment of the observations, about 540 days and that the main reason for its appearance is likely phase transition from amorphous to crystalline water ice activated at the heliocentric distance of 8.6 AU.

Korsun, P. P.; Chörny, G. F.

2003-11-01

145

Bearing capacity of desiccated tailings  

SciTech Connect

The development of matric suctions in soils contributes to their shear strength, resulting in an enhanced factor of safety against bearing-capacity failure. In this paper, matric suction profiles of desiccated mine tailings are predicted from a steady-state solution for evaporative conditions, and from an isothermal mathematical model that simulates liquid and vapor water flow through soils. The shear-strength envelope with respect to matric suction is established by testing reconstituted tailings samples in a modified triaxial cell, in which matric suction can be controlled. The contribution of matric suction to the shear strength is interpreted as an additional apparent cohesion for use in bearing-capacity calculations. Because of the nonlinearity of the shear-strength profile, a numerical method of analysis is adopted to predict the ultimate bearing capacity of the desiccated tailings. A subsequent decrease in bearing capacity following 2D water infiltration into a partially capped tailings deposit and accompanying suction loss is investigated.

Rassam, D.W.; Williams, D.J. [Univ. of Queensland, Brisbane, Queensland (Australia). Dept. of Civil Engineering

1999-07-01

146

Measles Viruses with Altered Envelope Protein Cytoplasmic Tails Gain Cell Fusion Competence  

PubMed Central

The cytoplasmic tail of the measles virus (MV) fusion (F) protein is often altered in viruses which spread through the brain of patients suffering from subacute sclerosing panencephalitis (SSPE). We transferred the coding regions of F tails from SSPE viruses in an MV genomic cDNA. Similarly, we constructed and transferred mutated tail-encoding regions of the other viral glycoprotein hemagglutinin (H) gene. From the mutated genomic cDNAs, we achieved rescue of viruses that harbor different alterations of the F tail, deletions in the membrane-distal half of the H tail, and combinations of these mutations. Viruses with alterations in any of the tails spread rapidly through the monolayer via enhanced cell-cell fusion. Double-tail mutants had even higher fusion competence but slightly decreased infectivity. Analysis of the protein composition of released mutant viral particles indicated that the tails are necessary for accurate virus envelope assembly and suggested a direct F tail-matrix (M) protein interaction. Since even tail-altered glycoproteins colocalized with M protein in intracellular patches, additional interactions may exist. We conclude that in MV infections, including SSPE, the glycoprotein tails are involved not only in virus envelope assembly but also in the control of virus-induced cell fusion.

Cathomen, Toni; Naim, Hussein Y.; Cattaneo, Roberto

1998-01-01

147

heterogeneous long-tailed sources  

Microsoft Academic Search

In this paper we consider a generalization of the so-called model where types of long-tailed sessions enter a buffer . The instantaneous rates of the sessions are functions of the occupancy of an system with long-tailed distributions. In particular we assume that a session of type transmits cells per unit time and lasts for a ran- dom time with long

Nikolay Likhanov; Ravi R. Mazumdar

148

Simulation of pyrite oxidation in fresh mine tailings under near-neutral conditions.  

PubMed

Sulphidic residual products from ore processing may produce acid rock drainage, when exposed to oxygen and water. Predictions of the magnitude of ARD and sulphide oxidation rates are of great importance in mine planning because they can be used to minimize or eliminate ARD and the associated economic and environmental costs. To address the lack of field data of sulphide oxidation rate in fresh sulphide-rich tailings under near-neutral conditions, determination and simulation of the rate was performed in pilot-scale at Kristineberg, northern Sweden. The quality of the drainage water was monitored, along with oxygen and carbon dioxide concentrations. The chemical composition of the solid tailings was also determined. The field data were compared to predictions from simulations of pyrite oxidation using a 1-D numerical model. The simulations' estimates of the amount of Fe and S released over a seven year period (52 kg and 178 kg, respectively) were in reasonably good agreement with those obtained by analysing the tailings (34 kg and 155 kg, respectively). The discrepancy is probably due to the formation of secondary precipitates such as iron hydroxides and gypsum; which are not accounted for in the model. The observed mass transport of Fe and S (0.05 and 1.0 kg per year, respectively) was much lower than expected on the basis of the simulations and the core data. Neutralization reactions involving carbonates in the tailings result in a near-neutral pH at all depths except at the oxidation front (pH < 5), indicating that the dissolution of carbonates was too slow for the acid to be neutralized, which instead neutralized deeper down in the tailings. This was also indicated by the reduced abundance of solid Ca at greater depths and the high levels of carbon dioxide both of which are consistent with the dissolution of carbonates. It could be concluded that the near-neutral pH in the tailings has no decreasing effect on the rate of sulphide oxidation, but does reduce the concentrations of dissolved elements in the drainage water due to the formation of secondary minerals. This means that sulphide oxidation rates may be underestimated if determined from drainage alone. PMID:22777533

Alakangas, Lena; Lundberg, Angela; Nason, Peter

2012-07-10

149

Genes involved in protein glycosylation determine the activity and cell internalization of the antifungal peptide PAF26 in Saccharomyces cerevisiae.  

PubMed

We have previously characterized the synthetic hexapeptide PAF26 as a cell-penetrating and non-lytic antifungal peptide that is active against Saccharomyces cerevisiae and filamentous fungi. Numerous cell wall (CW) proteins are glycosylated in fungi and many of these play important roles in fungal pathogenesis. In this study, we screened a collection of S. cerevisiae deletion mutants for protein glycosylation genes whose deletion altered the sensitivity to PAF26. Increased tolerance to PAF26 was observed in mutants with the following disrupted genes: PMT1-6, EOS1, ALG5, MNN1, MNN4 and MNN5. Significantly, genes coding for protein O-mannosyltransferase 2 (Pmt2p), which is responsible for the addition of the first mannosyl residue of O-linked carbohydrates, and for Eos1p, an enzyme involved in N-linked glycosylation of proteins, showed resistance to PAF26 and defects in CW integrity. Microscopic studies on the S. cerevisiae ?eos1 deletion mutant demonstrated a blockage of peptide internalization by cells. Protoplasts lacking CWs interacted with the peptide, but were more resistant to peptide killing than cells possessing CWs due to a blockage in PAF26 internalization. Interestingly, protoplasts obtained from ?eos1 behaved similarly to those of the parental strain. Collectively, these observations demonstrate that the CW is a positive factor that determines the internalization of the PAF26, and that Eos1p exerts its activity through the glycosylation of specific protein(s) involved in peptide internalization. PMID:23942187

Harries, Eleonora; Carmona, Lourdes; Muñoz, Alberto; Ibeas, José I; Read, Nick D; Gandía, Mónica; Marcos, Jose F

2013-08-11

150

Brain gene expression differences are associated with abnormal tail biting behavior in pigs.  

PubMed

Knowledge about gene expression in animals involved in abnormal behaviors can contribute to the understanding of underlying biological mechanisms. This study aimed to explore the motivational background to tail biting, an abnormal injurious behavior and severe welfare problem in pig production. Affymetrix microarrays were used to investigate gene expression differences in the hypothalamus and prefrontal cortex of pigs performing tail biting, pigs receiving bites to the tail and neutral pigs who were not involved in the behavior. In the hypothalamus, 32 transcripts were differentially expressed (P < 0.05) when tail biters were compared with neutral pigs, 130 when comparing receiver pigs with neutrals, and two when tail biters were compared with receivers. In the prefrontal cortex, seven transcripts were differently expressed in tail biters when compared with neutrals, seven in receivers vs. neutrals and none in the tail biters vs. receivers. In total, 19 genes showed a different expression pattern in neutral pigs when compared with both performers and receivers. This implies that the functions of these may provide knowledge about why the neutral pigs are not involved in tail biting behavior as performers or receivers. Among these 19 transcripts were genes associated with production traits in pigs (PDK4), sociality in humans and mice (GTF2I) and novelty seeking in humans (EGF). These are in line with hypotheses linking tail biting with reduced back fat thickness and explorative behavior. PMID:23146156

Brunberg, E; Jensen, P; Isaksson, A; Keeling, L J

2012-12-07

151

Source modification special study. [Uranium Mill Tailings Remedial Action Project  

SciTech Connect

One of the major issues that must be addressed during the evaluation of the efficiency of tailings embankment designs for compliance with groundwater standards is the estimation of source concentrations and the change in these concentrations with time. Because any effort to predict concentrations of contaminants in the uppermost aquifer requires a source concentration, data from these analyses are essential. Thetechnical approach of this study was twofold. The first approach was to investigate the rates of natural flushing of contaminants. Two sets of tailings samples were collected at two sites on the Old Rifle tailings pile at the Rifle UMTRA Project site in Colorado. One set of samples was collected at a site where the lower portion of the profile is continuously inundated with water and the other set was collected in anarea that only receives water from precipitation. The tailings samples were refluxed in strong acid (nitric acid) and the leachate was analyzed for hazardous constituents. The results of this investigation indicate that many of the hazardous constituents have been leached from the tailings at the wet site and that there has been little redistribution of elemental hazardous constituents at the dry site. The second approach involved a laboratory investigation of contaminant removal from tailings by doubly distilled water and two lixiviants. Tailings samples from the Gunnison, Colorado, UMTRA Project site were subjected to leaching by doubly distilled water, and by the lixiviants sodium bicarbonate and disodium ethylenediaminetetraacetic acid. The resulting data were tabulated and plotted with concentration as a function of pore volume. Evaluation of the data indicates that pore fluids should show a decrease in concentration after very few pore volumes of liquid have eluted through the tailings. It is also demonstrated that lixiviants significantly increase the solubility and rate of elution of all of the hazardous constituents.

Not Available

1989-04-01

152

Stand Still, a Drosophila Gene Involved in the Female Germline for Proper Survival, Sex Determination and Differentiation  

PubMed Central

We identified a new gene, stand still (stil), required in the female germline for proper survival, sex determination and differentiation. Three strong loss-of-function alleles were isolated. The strongest phenotype exhibited by ovaries dissected from adult females is the complete absence of germ cells. In other ovaries, the few surviving germ cells frequently show a morphology typical of primary spermatocytes. still is not required either for fly viability or for male germline development. The gene was cloned and found to encode a novel protein. still is strongly expressed in the female germ cells. Using P[stil(+)] transgenes, we show that stil and a closely localized gene are involved in the modification of the ovarian phenotypes of the dominant alleles of ovo caused by heterozygosity of region 49 A-D. The similarity of the mutant phenotypes of stil to that of otu and ovo suggests that the three genes function in a common or in parallel pathways necessary in the female germline for its survival, sex determination and differentiation.

Pennetta, G.; Pauli, D.

1997-01-01

153

Engaging Students through Web 2.0 Technologies: Capturing the Long Tail of Student Participation  

Microsoft Academic Search

This paper applies the relatively new concept of the Long Tail to classroom environments thereby offering a new way of viewing student participation and engagement. We suggest that Web 2.0 technologies such as forums and wikis will appeal to the Long Tail of low-involvement students to increase their interactions within learning environments in the same way that Internet search and

Nitin Aggarwal; Leslie Jordan Albert; Eric A. Walden; Shruti Kumthekar

2012-01-01

154

A multi-instrument view of tail reconnection at Saturn  

Microsoft Academic Search

Three instances of tail reconnection events at Saturn involving the ejection of plasmoids downtail have been reported by Jackman et al. (2007) using data from Cassini's magnetometer (MAG). Here we show two newly discovered events, as identified in the MAG data by northward\\/southward turnings and intensifications of the field. We discuss these events along with the original three, with the

C. M. Jackman; C. S. Arridge; N. Krupp; E. J. Bunce; D. G. Mitchell; H. J. McAndrews; M. K. Dougherty; C. T. Russell; N. Achilleos; G. H. Jones; A. J. Coates

2008-01-01

155

Flip, flop and fly: modulated motor control and highly variable movement patterns of autotomized gecko tails.  

PubMed

Many animals lose and regenerate appendages, and tail autotomy in lizards is an extremely well-studied example of this. Whereas the energetic, ecological and functional ramifications of tail loss for many lizards have been extensively documented, little is known about the behaviour and neuromuscular control of the autotomized tail. We used electromyography and high-speed video to quantify the motor control and movement patterns of autotomized tails of leopard geckos (Eublepharis macularius). In addition to rhythmic swinging, we show that they exhibit extremely complex movement patterns for up to 30 min following autotomy, including acrobatic flips up to 3 cm in height. Unlike the output of most central pattern generators (CPGs), muscular control of the tail is variable and can be arrhythmic. We suggest that the gecko tail is well suited for studies involving CPGs, given that this spinal preparation is naturally occurring, requires no surgery and exhibits complex modulation. PMID:19740891

Higham, Timothy E; Russell, Anthony P

2009-09-09

156

Flip, flop and fly: modulated motor control and highly variable movement patterns of autotomized gecko tails  

PubMed Central

Many animals lose and regenerate appendages, and tail autotomy in lizards is an extremely well-studied example of this. Whereas the energetic, ecological and functional ramifications of tail loss for many lizards have been extensively documented, little is known about the behaviour and neuromuscular control of the autotomized tail. We used electromyography and high-speed video to quantify the motor control and movement patterns of autotomized tails of leopard geckos (Eublepharis macularius). In addition to rhythmic swinging, we show that they exhibit extremely complex movement patterns for up to 30 min following autotomy, including acrobatic flips up to 3 cm in height. Unlike the output of most central pattern generators (CPGs), muscular control of the tail is variable and can be arrhythmic. We suggest that the gecko tail is well suited for studies involving CPGs, given that this spinal preparation is naturally occurring, requires no surgery and exhibits complex modulation.

Higham, Timothy E.; Russell, Anthony P.

2010-01-01

157

Fragility versus excessive crash involvement as determinants of high death rates per vehicle-mile of travel among older drivers  

Microsoft Academic Search

Using multiple national data systems, the roles of fragility (susceptibility to injury) versus excessive crash involvement in the increased fatality risk of older drivers per vehicle-mile of travel (VMT) were estimated. For each age and gender group, deaths per driver involved in a crash (a marker of fragility) and drivers involved in crashes per VMT (a marker of excessive crash

Guohua Li; Elisa R. Braver; Li-Hui Chen

2003-01-01

158

From light tails to heavy tails through multiplier  

Microsoft Academic Search

Let X and Y be two independent nonnegative random variables, of which X has a distribution belonging to the class or for some ????0 and Y is unbounded. We study how their product XY inherits the tail behavior of X. Under some mild technical assumptions we prove that the distribution of XY belongs to the class or accordingly. Hence, the

Qihe Tang

2008-01-01

159

Simultaneous Determination of Two Antibiotics in Tablets by Spectrophotometry and Principal Component Regression (PCR) Analysis. An Advanced Undergraduate Experiment Involving Chemometrics  

Microsoft Academic Search

An advanced analytical chemistry laboratory experiment involving the simultaneous determination of the antibiotics sulfamethoxazole and trimethoprime in commercial tablets is described. It involves the following steps: (1) preparation of nine calibration mixtures and the recording of their absorption spectra in the region 200–320 nm, (2) dissolution of the tablet contents and the recording of spectrophotometrics data, and (3) processing the

María E. Ribone; Ariana P. Pagani; Héctor C. Goicoechea; Alejandro C. Olivieri

2000-01-01

160

Myosin-II Tails Confer Unique Functions in Schizosaccharomyces pombe: Characterization of a Novel Myosin-II Tail  

PubMed Central

Schizosaccharomyces pombe has two myosin-IIs, Myo2p and Myp2p, which both concentrate in the cleavage furrow during cytokinesis. We studied the phenotype of mutant myosin-II strains to examine whether these myosins have overlapping functions in the cell. myo2+ is essential. myp2+ cannot rescue loss of myo2+ even at elevated levels of expression. myp2+ is required under specific nutritional conditions; thus myo2+ cannot rescue under these conditions. Studies with chimeras show that the tails rather than the structurally similar heads determine the gene-specific functions of myp2+ and myo2+. The Myo2p tail is a rod-shaped coiled-coil dimer that aggregates in low salt like other myosin-II tails. The Myp2p tail is monomeric in high salt and is insoluble in low salt. Biophysical properties of the full-length Myp2p tail and smaller subdomains indicate that two predicted coiled-coil regions fold back on themselves to form a rod-shaped antiparallel coiled coil. This suggests that Myp2p is the first type II myosin with only one head. The C-terminal two-thirds of Myp2p tail are essential for function in vivo and may interact with components of the salt response pathway.

Bezanilla, Magdalena; Pollard, Thomas D.

2000-01-01

161

Seasonal movements and home ranges of white-tailed deer in north-central South Dakota  

Microsoft Academic Search

Knowledge of movement patterns of white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) inhabiting landscapes intensively modified by agricultural systems is important to the present and future understanding of deer ecol- ogy. Little information exists regarding daily and seasonal movements of white-tailed deer in north-central South Dakota. Therefore, our goal was to determine movement patterns and home-range use of female white-tailed deer

T. W. Grovenburg; J. A. Jenks; R. W. Klaver; C. C. Swanson; C. N. Jacques; D. Todey

2009-01-01

162

An unbiased approach to identify genes involved in development in a turtle with temperature-dependent sex determination  

PubMed Central

Background Many reptiles exhibit temperature-dependent sex determination (TSD). The initial cue in TSD is incubation temperature, unlike genotypic sex determination (GSD) where it is determined by the presence of specific alleles (or genetic loci). We used patterns of gene expression to identify candidates for genes with a role in TSD and other developmental processes without making a priori assumptions about the identity of these genes (ortholog-based approach). We identified genes with sexually dimorphic mRNA accumulation during the temperature sensitive period of development in the Red-eared slider turtle (Trachemys scripta), a turtle with TSD. Genes with differential mRNA accumulation in response to estrogen (estradiol-17?; E2) exposure and developmental stages were also identified. Results Sequencing 767 clones from three suppression-subtractive hybridization libraries yielded a total of 581 unique sequences. Screening a macroarray with a subset of those sequences revealed a total of 26 genes that exhibited differential mRNA accumulation: 16 female biased and 10 male biased. Additional analyses revealed that C16ORF62 (an unknown gene) and MALAT1 (a long noncoding RNA) exhibited increased mRNA accumulation at the male producing temperature relative to the female producing temperature during embryonic sexual development. Finally, we identified four genes (C16ORF62, CCT3, MMP2, and NFIB) that exhibited a stage effect and five genes (C16ORF62, CCT3, MMP2, NFIB and NOTCH2) showed a response to E2 exposure. Conclusions Here we report a survey of genes identified using patterns of mRNA accumulation during embryonic development in a turtle with TSD. Many previous studies have focused on examining the turtle orthologs of genes involved in mammalian development. Although valuable, the limitations of this approach are exemplified by our identification of two genes (MALAT1 and C16ORF62) that are sexually dimorphic during embryonic development. MALAT1 is a noncoding RNA that has not been implicated in sexual differentiation in other vertebrates and C16ORF62 has an unknown function. Our results revealed genes that are candidates for having roles in turtle embryonic development, including TSD, and highlight the need to expand our search parameters beyond protein-coding genes.

2012-01-01

163

The cytoplasmic tail of lysosomal acid phosphatase contains overlapping but distinct signals for basolateral sorting and rapid internalization in polarized MDCK cells.  

PubMed Central

Lysosomal acid phosphatase (LAP) is synthesized as a type I membrane glycoprotein and targeted to lysosomes via the plasma membrane. Its cytoplasmic tail harbours a tyrosine-containing signal for rapid internalization. Expression in Madine-Darby canine kidney cells results in direct sorting to the basolateral cell surface, rapid endocytosis and delivery to lysosomes. In contrast, a deletion mutant lacking the cytoplasmic tail is delivered to the apical plasma membrane where it accumulates before it is slowly internalized. A chimeric protein, in which the cytoplasmic tail of LAP is fused to the extracytoplasmic and transmembrane domain of the apically sorted haemagglutinin, is sorted to the basolateral plasma membrane. A series of truncation and substitution mutants in the cytoplasmic tail was constructed and comparison of their polarized sorting and internalization revealed that the determinants for basolateral sorting and rapid internalization reside in the same segment of the cytoplasmic tail. The cytoplasmic factors decoding these signals, however, tolerate distinct mutations indicating that different receptors are involved in sorting at the trans-Golgi network and at the plasma membrane. Images

Prill, V; Lehmann, L; von Figura, K; Peters, C

1993-01-01

164

Recent radiochemistry observations at the Riverton and Maybell tailings piles  

SciTech Connect

Preliminary results are presented from the radiochemistry effort of the Lawrence Berkeley Laboratory integrated study of the inactive uranium mill tailings sites at Riverton, Wyoming and Maybell, Colorado. These results were obtained primarily by use of ..gamma..-ray spectrometric techniques, and included both field and laboratory application of NaI(Tl) crystal and Ge-semiconductor detector systems. Current interpretation of this evidence indicated there has been downward migration of uranium within the tailings column since its emplacement, and upward movement of several radionuclides from the tailings into the overlying cover material. The mechanisms responsible for these migrations are believed to involve fluid transport, and are further believed to be active at the present time.

Smith, A.R.; Moed, B.A.

1982-09-01

165

The Giacobini-Zinner magnetotail - Tail configuration and current sheet  

NASA Astrophysics Data System (ADS)

The high-resolution plasma electron and magnetic field data sets from the ICE tail traversal of comet Giacobini-Zinner have been combined to make a detailed study of the draped Giacobini-Zinner magnetotail in general, and its field-reversing current sheet in particular. The geometry of the magnetotail at the time of the ICE crossing is determined and is shown to be consistent with a circular tail cross section rotated 10°.5 in the normal sense of aberration and 9°.9 above the ecliptic plane, bisected by a cross-tail current sheet which is rotated 43° out of the ecliptic about the solar wind velocity vector. MHD continuity, momentum, and energy equations are combined with the plasma and field observations to determine unmeasured plasma properties at ICE and upstream at the average point along each streamline where the cometary ions are picked up.

McComas, D. J.; Gosling, J. T.; Bame, S. J.; Slavin, J. A.; Smith, E. J.; Steinberg, J. L.

1987-02-01

166

Risk analysis for seismic design of (tailings dams)  

SciTech Connect

Probabilistic seismic risk analysis is a promising method for evaluating design options and establishing seismic design parameters. However, there have been few examples in the literature to guide practitioners in its use. (This paper demonstrates the value of risk analysis for mine tailings dams and provides a case-history application for a seismically active portion of Nevada. Risk analysis provided the basis for selecting among design options having varying liquefaction resistance, and for establishing input parameters for dynamic analysis. Ranges are presented for the quantity and cleanup cost of tailings released in seismic failures to aid in determining expected failure consequences. It is shown that for many tailings dams, accepted lifetime failure probabilities of a few percent may provide a reasonable basis for probabilistic determination of seismic design criteria.)

Vick, S.G.; Atkinson, G.M.; Wilmot, C.I.

1985-07-01

167

Design of Dams for Mill Tailings.  

National Technical Information Service (NTIS)

The report describes tailings disposal problems at mines throughout the United States in order to identify design principles that can be applied to all types of dams for mill tailings. The circular reviews computer programs for stability analysis and phre...

C. D. Kealy R. L. Soderberg

1969-01-01

168

Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Naturita, Colorado  

SciTech Connect

The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (phase I), and the Ground Water Project (phase II). For the UMTRA Project site located near Naturita, Colorado (the Naturita site), phase I involves the removal of radioactively contaminated soils and materials and their transportation to a disposal site at Union Carbide Corporation`s Upper Burbank Repository at Uravan, Colorado, about 13 road miles (mi) (21 kilometers [km]) to the northwest. No uranium mill tailings are involved because the tailings were removed from the Naturita site and placed at Coke Oven, Colorado, during 1977 to 1979. Phase II of the project will evaluate the nature and extent of ground water contamination resulting from uranium processing and its effect on human health or the environment; and will determine site-specific ground water compliance strategies in accordance with the US Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. Human health risks could occur from drinking water pumped from a hypothetical well drilled in the contaminated ground water area. Environmental risks may result if plants or animals are exposed to contaminated ground water, or surface water that has received contaminated ground water. Therefore, a risk assessment is conducted for the Naturita site. This risk assessment report is the first site-specific document prepared for the Ground Water Project at the Naturita site. What follows is an evaluation of current and possible future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will be used to determine whether any action is needed to protect human health or the environment.

NONE

1995-08-01

169

Wave dynamics in the geomagnetic tail  

NASA Astrophysics Data System (ADS)

The Geomagnetic tail is the region of the earth's magnetosphere stretched by the solar wind away from the Sun. The stretched Geomagnetic tail acts as a huge magnetic energy reservoir powering a variety of processes, for instance the substorm and the aurora, which affect the entire magnetosphere. This thesis presents analyses of the wave dynamics of the geomagnetic tail at the spatial scale from the Magnetohydrodynamics (MHD) to the ion gyroradius and the temporal scale from the ion gyro-period to many gyro-periods. The results provide new insights into the energy flow process in the magnetotail reconnection. In addition, the implication of these results sheds light on the energy transport from the geomagnetic tail to the aurora zone. The bidirectional out owing ion jet is a diagnostic signal of magnetic reconnection. We present a Cluster spacecraft study of the intense surface waves in the earthward and tailward reconnection outflow jets in the geomagnetic tail. The four Cluster spacecraft are used to determine quantitatively the scale size and phase velocity of waves with spacecraft frequencies from 3 x 10-2 Hz to 1 Hz and spatial scales ranging from much larger (x50) than to comparable to the H+ gyroradius scale. The wave phase velocity relative to the spacecraft frame is directed mainly in the equatorial plane and it tracks the variation in the direction of the jet's velocity projection perpendicular to the magnetic field lying in the xy-gse plane. The surface waves are phase standing in the flow normal to the plasma sheet boundary, but partially or entirely convected by the flow in the plane of the plasma sheet (xy-gse). The surface wave is consistent with a Kelvin Helmholtz instability driven by the gradient in the normal direction of the component of the reconnection ion jet velocity perpendicular to magnetic field. E/B ratios provide evidence that dispersive Alfven waves are excited at small scales. Analysis of electric and magnetic field data shows that the wave perturbations are associated with strong Alfvenic Poynting flux radiated away from the reconnection region toward Earth along the geomagnetic field. The mapped values (to 100 km altitude) of Poynting flux (100ergs/cm2s) and longitudinal scales (10-100 km) of the waves suggest that the observed waves and their motions are an important boundary condition in determining both the energetics of the aurora and their complex motions in the night sky. The Harris current sheet is a good approximation of the Geomagnetic Tail configuration. We present a theoretical analysis of the linear Alfven eigenmode dynamics of a Harris current sheet. The implication of this theory in the context of magnetic reconnection is not presented. Alfven eigenmodes are confined by the Harris current sheet in the same way that quantum mechanical waves are confined by the tanh2 potential. Although the Alfven eigenmodes are confined in the current layer, their dynamics is interrelated with the global-scale information of the current sheet. The linear dynamics of the Harris current sheet is described as a eigenmode-source coupling process, during which magnetic energy can be converted into plasma energy and the first-order magnetic configuration of the Harris sheet alters.

Dai, Lei

170

Monitoring pool-tail fines  

NASA Astrophysics Data System (ADS)

Fine sediment < 2 and < 6 mm deposited in pool-tail areas of mountain streams is often measured to monitor changes in the supply of fines (e.g., by dam removal, bank erosion, or watershed effects including fires and road building) or to assess the status and trend of aquatic ecosystems. Grid counts, pebble counts, and volumetric bedmaterial samples are typically used to quantify pool-tail fines. Grid-count results exhibit a high degree of variability not only among streams and among operators, but also among crews performing a nearly identical procedure (Roper et al. 2010). Variability is even larger when diverse methods are employed, each of which quantifies fines in a different way: grid counts visually count surface fines on small patches within the pool-tail area, pebble counts pick up and tally surface particles along (riffle) transects, and volumetric samples sieve out fines from small-scale bulk samples; and even when delimited to pool-tail areas, individual methods focus on different sampling locales. Two main questions were analyzed: 1) Do pool-tail fines exhibit patterns of spatial variability and are some grid count schemes more likely to provide accurate results than others. 2) How and why does the percentage of fines vary among grid counts, pebble counts, and volumetric samples. In a field study, grids were placed at 7 locales in two rows across the wetted width of 10 pool tails in a 14-m wide 3rd order coarse gravel-bed mountain stream with <4% sand and <8% < 6 mm. Several pebble count transects were placed across each pool-tail area, and three volumetric samples were collected in each of three pool tails. Pebble and grid counts both indicated a fining trend towards one or both banks, sometimes interrupted by a secondary peak of fines within the central half of the wetted width. Among the five sampling schemes tested, grid counts covering the wetted width with 7 locales produced the highest accuracy and the least variability among the pools of the reach. Pebble counts between the two waterlines indicated 2-3 times more fines than grid counts, likely because grid counts did not extend exactly up to the waterline. However, when confined to the central 50% of the wetted width, grid counts indicated 1.2 and 1.6 times more fines < 2 and < 6 mm than pebble counts, likely because the plexiglass viewer used with grid counts improved the visibility of the bed. Volumetric armor layer samples (particles > 90 mm removed) indicated 1.4 and 1.2 times more fines < 2 and < 6 mm than grid counts at the same locales, while subarmor samples had 8-9 times more fines. In conclusion, methodological differences and the specific sampling locales selected by a method affect comparability of sampling results. Grid count accuracy and precision may be improved by extending both the width coverage and the sample size within a pool tail.

Bunte, K.; Potyondy, J. P.; Abt, S. R.; Swingle, K. W.

2010-12-01

171

Nature of axial tail instability and bubble-blob formation in near-Earth plasma sheet  

NASA Astrophysics Data System (ADS)

ABSTRACTPrevious global magnetohydrodynamic (MHD) simulations of substorm events have identified the dynamic presence of an axial tail instability that is uniform in the dawn-dusk direction in the near-Earth plasma sheet. The axial tail instability is found to be a major cause of the initial growing MHD force imbalance on closed field lines prior to the subsequent magnetic reconnection and substorm expansion onset processes. In this work, energy principle analysis indicates that a two-dimensional thin current sheet configuration in the magnetotail is typically stable to the axial mode within the framework of ideal MHD model. However, linear resistive MHD calculations find axial tail instabilities on closed field lines in the generalized Harris sheet configurations. The properties of these instabilities are similar to the axial tail modes observed in the global MHD simulations. The axial tail mode is unstable in regimes of low Lundquist number and regions with small normal component of magnetic field. Such resistive axial tail instability would by many researchers be considered as tearing instability in a two-dimensional tail configuration. Unlike the conventional tearing mode of Harris sheet, the linear axial tail instability does not involve any reconnection process. Instead, the nature of the mode is dominantly a slippage process among neighboring flux tubes as facilitated by resistive dissipation. A natural consequence of the axial tail instability is shown to be the formation of bubble-blob pairs in the pressure and entropy profiles in the near-Earth plasma sheet.

Zhu, P.; Raeder, J.; Hegna, C. C.; Sovinec, C. R.

2013-02-01

172

Transportation of the MOAB Uranium Mill Tailings to White Mesa Mill by Slurry Pipeline  

SciTech Connect

The Moab uranium mill tailings pile, located at the former Atlas Minerals Corporation site approximately three miles north of Moab, Utah, is now under the control of the US Department of Energy (''DOE''). The location of the tailings pile adjacent to the Colorado River, and the ongoing contamination of groundwater and seepage of pollutants into the river, have lead to the investigation, as part of the final site remediation program, of alternatives to relocate the tailings to a qualified permanent disposal site. This paper will describe the approach being taken by the team formed between International Uranium (USA) Corporation (''IUC'') and Washington Group International (''WGINT'') to develop an innovative technical proposal to relocate the Moab tailings to IUC's White Mesa Mill south of Blanding, Utah. The proposed approach for relocating the tailings involves using a slurry pipeline to transport the tailings to the White Mesa Mill. The White Mesa Mill is a fully licensed, active uranium mill site that is uniquely suited for permanent disposal of the Moab tailings. The tailings slurry would be dewatered at the White Mesa Mill, the slurry water would be recycled to the Moab site for reuse in slurry makeup, and the ''dry'' tailings would be permanently disposed of in an approved below grade cell at the mill site.

Hochstein, R. F.; Warner, R.; Wetz, T. V.

2003-02-26

173

RADEMACHER CHAOS: TAIL ESTIMATES VS LIMIT THEOREMS  

Microsoft Academic Search

We study Rademacher chaos indexed by a sparse set which has a fractional combinatorial dimension. We obtain tail estimates for finite sums and a normal limit theorem as the size tends to infinity. The tails for finite sums may be much larger that the tails of the limit.

RON BLEI; SVANTE JANSON

2003-01-01

174

Anaplasma phagocytophilum in White-tailed Deer  

Microsoft Academic Search

We examined the reservoir potential of white-tailed deer for Anaplasma phagocytophilum. Results suggest that white-tailed deer harbor a variant strain not associated with human infection, but contrary to published reports, white- tailed deer are not a reservoir for strains that cause human disease. These results will affect surveillance studies of vector and reservoir populations.

Robert F. Massung; Joshua W. Courtney; Shannon L. Hiratzka; Virginia E. Pitzer; Gary Smith; Richard L. Dryden

175

Atomic structure of bacteriophage Sf6 tail needle knob.  

PubMed

Podoviridae are double-stranded DNA bacteriophages that use short, non-contractile tails to adsorb to the host cell surface. Within the tail apparatus of P22-like phages, a dedicated fiber known as the "tail needle" likely functions as a cell envelope-penetrating device to promote ejection of viral DNA inside the host. In Sf6, a P22-like phage that infects Shigella flexneri, the tail needle presents a C-terminal globular knob. This knob, absent in phage P22 but shared in other members of the P22-like genus, represents the outermost exposed tip of the virion that contacts the host cell surface. Here, we report a crystal structure of the Sf6 tail needle knob determined at 1.0 ? resolution. The structure reveals a trimeric globular domain of the TNF fold structurally superimposable with that of the tail-less phage PRD1 spike protein P5 and the adenovirus knob, domains that in both viruses function in receptor binding. However, P22-like phages are not known to utilize a protein receptor and are thought to directly penetrate the host surface. At 1.0 ? resolution, we identified three equivalents of l-glutamic acid (l-Glu) bound to each subunit interface. Although intimately bound to the protein, l-Glu does not increase the structural stability of the trimer nor it affects its ability to self-trimerize in vitro. In analogy to P22 gp26, we suggest the tail needle of phage Sf6 is ejected through the bacterial cell envelope during infection and its C-terminal knob is threaded through peptidoglycan pores formed by glycan strands. PMID:21705802

Bhardwaj, Anshul; Molineux, Ian J; Casjens, Sherwood R; Cingolani, Gino

2011-06-25

176

Word of Mouth and Recommender Systems: A Theory of the Long Tail  

Microsoft Academic Search

I present a model to assess the extent to which recommender systems can account for the 'long tail', an increase in the tail of the sales distribution. Consumers face a search problem within a pool of horizontally dierentiated products supplied by a monopolist. They are endowed with a taste pro…le that determines their probability of matching with any given product,

Andres Hervas-Draney

177

EVALUATION OF IVERMECTIN FOR TREATMENT OF HAIR LOSS SYNDROME IN BLACK-TAILED DEER  

Microsoft Academic Search

Since 1997, numerous Columbian black-tailed deer (Odocoileus hemionus columbi- anus) in western Washington (USA) have developed a hair loss syndrome that often preceded emaciation, debilitation, pneumonia, and death. To study this syndrome, eight affected free- ranging Columbian black-tailed deer fawns were captured from western Washington in February 1999 to determine the effect of ivermectin treatment. Fecal examinations indicated that the

Louis Bender

2004-01-01

178

INTERSPECIFIC COMPETITION BETWEEN WHITE-TAILED, FALLOW , RED, AND ROE DEER  

Microsoft Academic Search

We conducted a series of studies in the Dobríš Forest, Czech Republic, to determine whether competitio n between white-tailed deer (Odocoileus virginianu s) and sympatric cervid species could limit expansion of the whit e - tail population. We used grazing time among species as an indication of potential interspecific competition an d predicted that grazing time on an open pasture

KARL V. MILLER; Daniel B. Warnell

179

Hydrochemistry at the Falls City Uranium Mine Tailings Remedial Action Project, Karnes County, Texas  

Microsoft Academic Search

Acidic tailings and tailings solutions, created by sulfuric acid processing of uranium ores, were disposed on the outcrop of the Whitsett Formation (Eocene). These solutions have recharged the sandstones of the Whitsett since the 1960s. Previous work found a large, complex, and unexplained pattern of contamination. The present study determined the extent and nature of contamination by (1) characterizing the

T. J. Jackson; C. W. Kreitler

1994-01-01

180

Physical modeling of marginally stable tailings dams using centrifuge simulation techniques  

Microsoft Academic Search

The stability of a marginally stable tailings dam is investigated using centrifuge simulations and flow and stability analyses. The centrifuge simulations are conducted on Sandia's large radius machine using tailings from a coal mine. Pore pressure measurements and photographic coverage of the phreatic surface permit the determination of the flow field developed in the dam. The simulations investigate the effects

H. J. Sutherland; R. P. Rechard; A. A. Heckes

1984-01-01

181

Extracting aluminum from dross tailings  

NASA Astrophysics Data System (ADS)

Aluminum dross tailings, an industrial waste, from the Egyptian Aluminium Company (Egyptalum) was used to produce two types of alums: aluminum-sulfate alum [itAl2(SO4)3.12H2O] and ammonium-aluminum alum [ (NH 4)2SO4AL2(SO4)3.24H2O]. This was carried out in two processes. The first process is leaching the impurities using diluted H2SO4 with different solid/liquid ratios at different temperatures to dissolve the impurities present in the starting material in the form of solute sulfates. The second process is the extraction of aluminum (as aluminum sulfate) from the purifi ed aluminum dross tailings thus produced. The effects of temperature, time of reaction, and acid concentration on leaching and extraction processes were studied. The product alums were analyzed using x-ray diffraction and thermal analysis techniques.

Amer, A. M.

2002-11-01

182

Aeroelastic Characteristics of the AH-64 Bearingless Tail Rotor.  

National Technical Information Service (NTIS)

The results of a wind tunnel test program to determine the performance loads and dynamic characteristics of the Composite Flexbeam Tail Rotor (CFTR) for the AH-64 Advanced Attack Helicopter are reported. The CFTR uses an elastomeric shear attachment of th...

D. Banerjee

1988-01-01

183

Selective Flotation of Minerals from North Carolina Mica Tailing.  

National Technical Information Service (NTIS)

Laboratory batch and small-scale continuous flotation tests were conducted on a mica waste tailing from Kings Mountain, N.C., to determine the feasibility of producing high-quality mica, feldspar, and glass sand. Mica was recovered by two methods; one was...

W. H. Eddy J. S. Browning J. E. Hardemon

1969-01-01

184

Application of tailings flow analyses to field conditions  

SciTech Connect

Catastrophic failures of tailings impoundments, in which liquefied tailings flow over substantial distances, pose severe hazards to the health and safety of people in downstream areas, and have a potential for economic and environmental devastation. The purpose of this study, an extension of prior investigations, was to develop procedures to measure Bingham flow parameters for mine tailings. In addition, the analytical procedures developed by Lucia (1981) and Jeyapalan (1980) for predicting the consequences of tailings flow failures were evaluated and applied to the Tenmile Tailings Pond at Climax, Colorado. Revisions in the simplified equilibrium procedure, developed by Lucia (1981), make it more compatible with infinite slope solutions. Jeyapalan's model was evaluated using a simple rheological analogy, and it appears there are some numerical difficulties with the operation of the computer program TFLOW used to model the displacements and velocities of flow slides. Comparable flow distances can be determined using either model if the flow volume used in the simplified equilibrium procedure is estimated properly. When both analytical procedures were applied to the Tenmile Pond, it was concluded there was no potential for a flow slide at the site.

Bryant, S.M.

1983-01-01

185

Curved tails in polymerization-based bacterial motility  

NASA Astrophysics Data System (ADS)

The curved actin ``comet-tail'' of the bacterium Listeria monocytogenes is a visually striking signature of actin polymerization-based motility. Similar actin tails are associated with Shigella flexneri, spotted-fever Rickettsiae, the Vaccinia virus, and vesicles and microspheres in related in vitro systems. We show that the torque required to produce the curvature in the tail can arise from randomly placed actin filaments pushing the bacterium or particle. We find that the curvature magnitude determines the number of actively pushing filaments, independent of viscosity and of the molecular details of force generation. The variation of the curvature with time can be used to infer the dynamics of actin filaments at the bacterial surface.

Rutenberg, Andrew D.; Grant, Martin

2001-08-01

186

[Leaching kinetics of josephinite tailings with sulfuric acid].  

PubMed

Leaching is the most important step of josephinite tailing recycle technology. This step can separate the valuable metal Mg from Si and other impure metal. Effects of sulfuric acid on leaching Mg efficiency from josephinite tailings were investigated. To obtain the leaching behavior, a modified unreacted shrinking core model that based on the experimental data was used to determine the dissolution kinetic parameters. The model was significant and showed that the dissolution of Mg2+ in josephinite tailing was controlled by the produce layer diffusion, apparent activation reaction energy E = 34.04 kJ x mol(-1). The produce layers obstruct the forward reaction of the dissolution of Mg2+. PMID:24028005

Chen, An-An; Zhou, Shao-Qi; Huang, Peng-Fei

2013-07-01

187

Testing the functional significance of tail streamers  

PubMed Central

Studies of the evolution of elaborate ornaments have concentrated on their role in increasing attractiveness to mates. The classic examples of such sexually selected structures are the elongated tails of some bird species. Elongated tails can be divided into three categories: graduated tails, pin tails and streamers. There seems to be little debate about whether graduated and pin tails are ornaments; i.e. costly signals used in mate choice. However, in the case of streamers there is considerable discussion about their function. It has been suggested that tail streamers could be (i) entirely naturally selected, (ii) entirely sexually selected, (iii) partly naturally and partly sexually selected. The prime example of a species with tail streamers is the swallow (Hirundo rustica) in which both sexes have tail streamers. In this paper we discuss the aerodynamic consequences of different types of manipulation of the streamer and/or outer tail feather. We make qualitative predictions about the aerodynamic performance of swallows with manipulated tail streamers; these predictions differ depending on whether streamers have a naturally or sexually selected function. We demonstrate that these hypotheses can only be separated if tail streamers are shortened and changes in aerodynamic performance measured during turning flight.

Evans, M. R.; Thomas, A. L. R.

1997-01-01

188

Spatial Coordination of Kindlin-2 with Talin Head Domain in Interaction with Integrin ? Cytoplasmic Tails*  

PubMed Central

Both talin head domain and kindlin-2 interact with integrin ? cytoplasmic tails, and they function in concert to induce integrin activation. Binding of talin head domain to ? cytoplasmic tails has been characterized extensively, but information on the interaction of kindin-2 with this integrin segment is limited. In this study, we systematically examine the interactions of kindlin-2 with integrin ? tails. Kindlin-2 interacted well with ?1 and ?3 tails but poorly with the ?2 cytoplasmic tail. This binding selectivity was determined by the non-conserved residues, primarily the three amino acids at the extreme C terminus of the ?3 tail, and the sequence in ?2 was non-permissive. The region at the C termini of integrin ?1 and ?3 tails recognized by kindlin-2 was a binding core of 12 amino acids. Kindlin-2 and talin head do not interact with one another but can bind simultaneously to the integrin ?3 tail without enhancing or inhibiting the interaction of the other binding partner. Kindlin-2 itself failed to directly unclasp integrin ?/? tail complex, indicating that kindlin-2 must cooperate with talin to support the integrin activation mechanism.

Bledzka, Kamila; Liu, Jianmin; Xu, Zhen; Perera, H. Dhanuja; Yadav, Satya P.; Bialkowska, Katarzyna; Qin, Jun; Ma, Yan-Qing; Plow, Edward F.

2012-01-01

189

Spatial coordination of kindlin-2 with talin head domain in interaction with integrin ? cytoplasmic tails.  

PubMed

Both talin head domain and kindlin-2 interact with integrin ? cytoplasmic tails, and they function in concert to induce integrin activation. Binding of talin head domain to ? cytoplasmic tails has been characterized extensively, but information on the interaction of kindin-2 with this integrin segment is limited. In this study, we systematically examine the interactions of kindlin-2 with integrin ? tails. Kindlin-2 interacted well with ?(1) and ?(3) tails but poorly with the ?(2) cytoplasmic tail. This binding selectivity was determined by the non-conserved residues, primarily the three amino acids at the extreme C terminus of the ?(3) tail, and the sequence in ?(2) was non-permissive. The region at the C termini of integrin ?(1) and ?(3) tails recognized by kindlin-2 was a binding core of 12 amino acids. Kindlin-2 and talin head do not interact with one another but can bind simultaneously to the integrin ?(3) tail without enhancing or inhibiting the interaction of the other binding partner. Kindlin-2 itself failed to directly unclasp integrin ?/? tail complex, indicating that kindlin-2 must cooperate with talin to support the integrin activation mechanism. PMID:22648415

Bledzka, Kamila; Liu, Jianmin; Xu, Zhen; Perera, H Dhanuja; Yadav, Satya P; Bialkowska, Katarzyna; Qin, Jun; Ma, Yan-Qing; Plow, Edward F

2012-05-30

190

The crystal structure of bacteriophage HK97 gp6: defining a large family of head-tail connector proteins.  

PubMed

The final step in the morphogenesis of long-tailed double-stranded DNA bacteriophages is the joining of the DNA-filled head to the tail. The connector is a specialized structure of the head that serves as the interface for tail attachment and the point of egress for DNA from the head during infection. Here, we report the determination of a 2.1 A crystal structure of gp6 of bacteriophage HK97. Through structural comparisons, functional studies, and bioinformatic analysis, gp6 has been determined to be a component of the connector of phage HK97 that is evolutionarily related to gp15, a well-characterized connector component of bacteriophage SPP1. Whereas the structure of gp15 was solved in a monomeric form, gp6 crystallized as an oligomeric ring with the dimensions expected for a connector protein. Although this ring is composed of 13 subunits, which does not match the symmetry of the connector within the phage, sequence conservation and modeling of this structure into the cryo-electron microscopy density of the SPP1 connector indicate that this oligomeric structure represents the arrangement of gp6 subunits within the mature phage particle. Through sequence searches and genomic position analysis, we determined that gp6 is a member of a large family of connector proteins that are present in long-tailed phages. We have also identified gp7 of HK97 as a homologue of gp16 of phage SPP1, which is the second component of the connector of this phage. These proteins are members of another large protein family involved in connector assembly. PMID:19895817

Cardarelli, Lia; Lam, Robert; Tuite, Ashleigh; Baker, Lindsay A; Sadowski, Paul D; Radford, Devon R; Rubinstein, John L; Battaile, Kevin P; Chirgadze, Nickolay; Maxwell, Karen L; Davidson, Alan R

2009-11-04

191

Determinants of Substance Abuse in a Population of Children and Adolescents Involved with the Child Welfare System  

ERIC Educational Resources Information Center

|Substance abuse is an important health issue facing children involved with child welfare, but little is known about the associated factors. The purpose of this study was to build on findings from the "Canadian Incidence Study of Reported Child Abuse and Neglect-2003" and use a national sample of 10-15 year old children to examine the factors…

Singh, Veeran-Anne S.; Thornton, Tiffany; Tonmyr, Lil

2011-01-01

192

Enhancing the safety of tailings management facilities  

SciTech Connect

Unsafe tailings management facilities (TMFs) have caused serious accidents in Europe threatening human health/life and the environment. While advanced design, construction and management procedures are available, their implementation requires greater emphasis. An integrated research project funded by the European Union was carried out between 2002 and 2005 with the overall goal of improving the safety of TMFs (Sustainable Improvement in Safety of Tailings Facilities - TAILSAFE, http://www.tailsafe.com/). The objective of TAILSAFE was to develop and apply methods of parameter evaluation and measurement for the assessment and improvement of the safety state of tailings facilities, with particular attention to the stability of tailings dams and slurries, the special risks inherent when such materials include toxic or hazardous wastes, and authorization and management procedures for tailings facilities. Aspects of tailings facilities design, water management and slurry transport, non-destructive and minimally intrusive testing methods, monitoring and the application of sensors, intervention and remediation options were considered in TAILSAFE. A risk reduction framework (the TAILSAFE Parameter Framework) was established to contribute to the avoidance of catastrophic accidents and hazards from tailings facilities. Tailings from the mining and primary processing of metals, minerals and coal were included within the scope of TAILSAFE. The project focused on the avoidance of hazards by developing procedures and methods for investigating and improving the stability of tailings dams and tailings bodies.

Meggyes, T.; Niederleithinger, E.; Witt, K.J.; Csovari, M.; Kreft-Burman, K.; Engels, J.; McDonald, C.; Roehl, K.E. [BAM, Berlin (Germany). Federal Institute for Material Research & Testing

2008-07-01

193

Involvement of autophagy and mitochondrial dynamics in determining the fate and effects of irreparable mitochondrial DNA damage.  

PubMed

Mitochondrial DNA (mtDNA) is different in many ways from nuclear DNA. A key difference is that certain types of DNA damage are not repaired in the mitochondrial genome. What, then, is the fate of such damage? What are the effects? Both questions are important from a health perspective because irreparable mtDNA damage is caused by many common environmental stressors including ultraviolet C radiation (UVC). We found that UVC-induced mtDNA damage is removed slowly in the nematode Caenorhabditis elegans via a mechanism dependent on mitochondrial fusion, fission, and autophagy. However, knockdown or knockout of genes involved in these processes—many of which have homologs involved in human mitochondrial diseases—had very different effects on the organismal response to UVC. Reduced mitochondrial fission and autophagy caused no or small effects, while reduced mitochondrial fusion had dramatic effects. PMID:22929123

Meyer, Joel N; Bess, Amanda S

2012-12-01

194

Uranium mill tailings neutralization: contaminant complexation and tailings leaching studies  

SciTech Connect

Laboratory experiments were performed to compare the effectiveness of limestone (CaCO/sub 3/) and hydrated lime (Ca(OH)/sub 2/) for improving waste water quality through the neutralization of acidic uranium mill tailings liquor. The experiments were designed to also assess the effects of three proposed mechanisms - carbonate complexation, elevated pH, and colloidal particle adsorption - on the solubility of toxic contaminants found in a typical uranium mill waste solution. Of special interest were the effects each of these possible mechanisms had on the solution concentrations of trace metals such as Cd, Co, Mo, Zn, and U after neutralization. Results indicated that the neutralization of acidic tailings to a pH of 7.3 using hydrated lime provided the highest overall waste water quality. Both the presence of a carbonate source or elevating solution pH beyond pH = 7.3 resulted in a lowering of previously achieved water quality, while adsorption of contaminants onto colloidal particles was not found to affect the solution concentration of any constituent investigated. 24 refs., 8 figs., 19 tabs.

Opitz, B.E.; Dodson, M.E.; Serne, R.J.

1985-05-01

195

The Pattern of Mutational Involvement of RAS Genes in Human Hematologic Malignancies Determined by DNA Amplification and Direct Sequencing  

Microsoft Academic Search

DNA from 161 patients with various forms of hematologic malignancies were investigated for mutations in exons 1 and 2 of the N-RAS. K-RAS and Ha-RAS gene by direct sequencing of DNA amplified in vitro by the polymerase chain reaction. Mutations involving either codons 11,12, or 13 of the N-RAS gene were identified in 18 of the 161 patients. The relative

H. G. Ahuja; A. Foti; M. Bar-Eli; M. J. Cline

1990-01-01

196

Determinants of Substance Abuse in a Population of Children and Adolescents Involved with the Child Welfare System  

Microsoft Academic Search

Substance abuse is an important health issue facing children involved with child welfare, but little is known about the associated\\u000a factors. The purpose of this study was to build on findings from the Canadian Incidence Study of Reported Child Abuse and Neglect-2003 and use a national sample of 10–15 year old children to examine the factors associated with substance abuse for

Veeran-Anne S. Singh; Tiffany Thornton; Lil Tonmyr

197

Mental health challenges and strengths of street-involved youth: the need for a multi-determined approach.  

PubMed

The social environments and activities of homeless youth frequently create a downward spiral, leading to drug abuse and survival sex as well as self-harm behaviours and suicidality. This study employed a mixed-methods approach to assess the mental health challenges and strengths of street-involved youth. A convenience sample of 70 homeless young people completed a series of standardized questionnaires evaluating mental health symptoms as well as resilience and self-esteem. Two focus groups were also held to capture the perceived mental health needs of street-involved youth. These young people (aged 16-24) were found to have high levels of mental health symptoms compared to other groups of young adults. However, they also exhibited moderately high levels of resilience and self-esteem. Therefore, multi-component mental health programs and interventions that address both strengths and challenges may well help street-involved youth to work towards social re-integration and, ultimately, improved quality of life. PMID:21086775

McCay, Elizabeth; Langley, John; Beanlands, Heather; Cooper, Linda; Mudachi, Naomi; Harris, Andrea; Blidner, Rebecca; Bach, Karen; Dart, Colin; Howes, Carol; Miner, Susan

2010-09-01

198

8 CFR 208.31 - Reasonable fear of persecution or torture determinations involving aliens ordered removed under...  

Code of Federal Regulations, 2013 CFR

... DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS PROCEDURES FOR ASYLUM...208.9(c). (e) Referral to Immigration Judge. If an asylum officer determines...I-863, Notice of Referral to the Immigration Judge, for full consideration of...

2013-01-01

199

Size-partitioning of an urban aerosol to identify particle determinants involved in the proinflammatory response induced in airway epithelial cells  

Microsoft Academic Search

BACKGROUND: The contribution of air particles in human cardio-respiratory diseases has been enlightened by several epidemiological studies. However the respective involvement of coarse, fine and ultrafine particles in health effects is still unclear. The aim of the present study is to determine which size fraction from a chemically characterized background aerosol has the most important short term biological effect and

Kiran Ramgolam; Olivier Favez; Hélène Cachier; Annie Gaudichet; Francelyne Marano; Laurent Martinon; Armelle Baeza-Squiban

2009-01-01

200

Determination of the Active Principle in a Syrup by Spectrophotometry and Principal Component Regression Analysis. An Advanced Undergraduate Experiment Involving Chemometrics  

Microsoft Academic Search

An advanced analytical chemistry laboratory experiment concerning the determination of the mucolitic bromhexine in a commercial syrup is described. It involves the following steps: (i) preparing nine calibration mixtures and recording their absorption spectra in the region 285-348 nm, (ii) recording spectrophotometric data for four synthetic unknowns and two commercial samples, and (iii) processing them with the multivariate calibration technique

María É. Ribone; Ariana P. Pagani; Alejandro C. Olivieri; Héctor C. Goicoechea

2000-01-01

201

Extracting aluminum from dross tailings  

Microsoft Academic Search

Aluminum dross tailings, an industrial waste, from the Egyptian Aluminium Company (Egyptalum) was used to produce two types\\u000a of alums: aluminum-sulfate alum [itAl2(SO4)3.12H2O]and ammonium-aluminum alum [(NH\\u000a 4)2SO4AL2(SO4)3.24H2O]. This was carried out in two processes. The first process is leaching the impurities using diluted H2SO4 with different solid\\/liquid ratios at different temperatures to dissolve the impurities present in the starting material

A. M. Amer

2002-01-01

202

Extracting aluminum from dross tailings  

Microsoft Academic Search

Aluminum dross tailings, an industrial waste, from the Egyptian Aluminium Company (Egyptalum) was used to produce two types of alums: aluminum-sulfate alum [itAl2(SO4)3.12H2O] and ammonium-aluminum alum [ (NH 4)2SO4AL2(SO4)3.24H2O]. This was carried out in two processes. The first process is leaching the impurities using diluted H2SO4 with different solid\\/liquid ratios at different temperatures to dissolve the impurities present in the

A. M. Amer

2002-01-01

203

Cassini/CAPS observations of duskside tail dynamics at Saturn  

NASA Astrophysics Data System (ADS)

properties of Saturn's premidnight tail region are surveyed using Cassini/Cassini Plasma Spectrometer (CAPS) ion observations from 2010. Only low-latitude (|lat| < 6°) intervals in which the CAPS viewing was roughly symmetric inward and outward around the corotation direction are used. Our numerical moments algorithm returns nonzero ion density for 70% (999) of the intervals selected. Of these, 642 had detectable water-group ion densities, and the remainder were dominantly, if not entirely, light ions. The derived plasma parameters are similar to those found in an earlier study for the postmidnight tail region, except that we find little evidence for the systematic outflows identified in that study, and we do find numerous significant inflow events. One such inflow is identified as a dipolarization event, the first reported plasma properties of such a structure at Saturn. A second, long-lasting event may be evidence for the existence at times of a quasi-steady reconnection region in the premidnight tail. The large majority of the plasma flows are found to be within 20° of the corotation direction, though with flow speeds significantly lower than full corotation. While the inflow events represent plausible evidence for internally driven mass loss in the premidnight region, the absence of significant outflow events suggests that in the region surveyed here, tail reconnection has not yet proceeded to involve lobe field lines, so the disconnected plasma continues its general motion in the corotation direction.

Thomsen, M. F.; Wilson, R. J.; Tokar, R. L.; Reisenfeld, D. B.; Jackman, C. M.

2013-09-01

204

Anatomy of a Lactococcal Phage Tail  

PubMed Central

Bacteriophages of the Siphoviridae family utilize a long noncontractile tail to recognize, adsorb to, and inject DNA into their bacterial host. The tail anatomy of the archetypal Siphoviridae ? has been well studied, in contrast to phages infecting gram-positive bacteria. This report outlines a detailed anatomical description of a typical member of the Siphoviridae infecting a gram-positive bacterium. The tail superstructure of the lactococcal phage Tuc2009 was investigated using N-terminal protein sequencing, Western blotting, and immunogold transmission electron microscopy, allowing a tangible path to be followed from gene sequence through encoded protein to specific architectural structures on the Tuc2009 virion. This phage displays a striking parity with ? with respect to tail structure, which reenforced a model proposed for Tuc2009 tail architecture. Furthermore, comparisons with ? and other lactococcal phages allowed the specification of a number of genetic submodules likely to encode specific tail structures.

Mc Grath, Stephen; Neve, Horst; Seegers, Jos F. M. L.; Eijlander, Robyn; Vegge, Christina S.; Br?ndsted, Lone; Heller, Knut J.; Fitzgerald, Gerald F.; Vogensen, Finn K.; van Sinderen, Douwe

2006-01-01

205

On links and tails in Italian  

Microsoft Academic Search

Adopting Vallduví’s partition of the background into link and tail, I provide an account for Italian data. Being links pre-focal expressions, and tails post-focal, right dislocated expressions, I claim that links are shifting topics, while tails are discourse-given material. I show that a link is not iterated in discourse as long as the topic does not shift. If a link

Lisa Brunetti

2009-01-01

206

The evolution of e-tailing  

Microsoft Academic Search

The evolutionary perspective is applied to e-tailing in an attempt to capture and assess its past and projected future evolution. In the dynamics of e-tailing's evolutionary change, a four-phase pattern of process is uncovered. It shows the e-tailing ‘revolution’ was part of a longer evolutionary process. The findings and implications are integrated and applied with the evolutionary literature to offer

David E. Williams

2009-01-01

207

Tails of waiting times and their bounds  

Microsoft Academic Search

Tails of distributions having the form of the geometric convolution are considered. In the case of light-tailed summands,\\u000a a simple proof of the famous Cramér asymptotic formula is given via the change of probability measure. Some related results\\u000a are obtained, namely, bounds of the tails of geometric convolutions, expressions for the distribution of the 1st failure time\\u000a and failure rate

Vladimir Kalashnikov; Gurami Tsitsiashvili

1999-01-01

208

Evidence for the long-term stability of uranium mill tailings: survivability of ancient man-made earthern structures  

Microsoft Academic Search

Pacific Northwest Laboratory (PNL), as part of a study for the Nuclear Regulatory Commission (NRC), is investigating long-term stabilization techniques for uranium mill tailings piles. Part of this invetigation involves the design of a rock armoring blanket to mitigate wind and water erosion of the underlying soil cover, which, in turn, prevents exposure of the tailings to the environment. However,

C. G. Lindsey; J. Mishima

1982-01-01

209

Students' Perceptions of a Highly Controversial yet Keystone Species, the Black-Tailed Prairie Dog: A Case Study  

ERIC Educational Resources Information Center

|The authors used a case-study methodology to explore the perceptions of 30 9th-grade biology students relative to black-tailed prairie dogs. The case study, which involved classroom- and field-based experiences that focused on black-tailed prairie dogs, revealed 3 major themes: apathy, egocentrism, and naive conceptions. The authors had hoped…

Fox-Parrish, Lynne; Jurin, Richard R.

2008-01-01

210

Sex chromosome aberrations and stature: deduction of the principal factors involved in the determination of adult height  

Microsoft Academic Search

Although sex chromosome aberrations are frequently associated with statural changes, the underlying factors have not been clarified. To define the factors leading to the statural changes, we took the following three steps: (1) determination of the mean adult height in non-mosaic Caucasian patients with sex chromosome aberrations reported in the literature (assessment of genetic height potential); (2) assessment of the

Tsutomu Ogata; Nobutake Matsuo

1993-01-01

211

A Randomised Controlled Trial to Determine the Effectiveness of an Early Psychological Intervention with Children Involved in Road Traffic Accidents  

ERIC Educational Resources Information Center

Objective: To determine whether an early intervention using a psychological debriefing format is effective in preventing psychological distress in child road traffic accident survivors. Design: Randomised controlled trial. Setting: Accident and Emergency Department, Royal United Hospital, Bath. Subjects: 158 children aged 7-18. Follow-up…

Stallard, Paul; Velleman, Richard; Salter, Emma; Howse, Imogen; Yule, William; Taylor, Gordon

2006-01-01

212

A Randomised Controlled Trial to Determine the Effectiveness of an Early Psychological Intervention with Children Involved in Road Traffic Accidents  

ERIC Educational Resources Information Center

|Objective: To determine whether an early intervention using a psychological debriefing format is effective in preventing psychological distress in child road traffic accident survivors. Design: Randomised controlled trial. Setting: Accident and Emergency Department, Royal United Hospital, Bath. Subjects: 158 children aged 7-18. Follow-up…

Stallard, Paul; Velleman, Richard; Salter, Emma; Howse, Imogen; Yule, William; Taylor, Gordon

2006-01-01

213

Active tails enhance arboreal acrobatics in geckos.  

PubMed

Geckos are nature's elite climbers. Their remarkable climbing feats have been attributed to specialized feet with hairy toes that uncurl and peel in milliseconds. Here, we report that the secret to the gecko's arboreal acrobatics includes an active tail. We examine the tail's role during rapid climbing, aerial descent, and gliding. We show that a gecko's tail functions as an emergency fifth leg to prevent falling during rapid climbing. A response initiated by slipping causes the tail tip to push against the vertical surface, thereby preventing pitch-back of the head and upper body. When pitch-back cannot be prevented, geckos avoid falling by placing their tail in a posture similar to a bicycle's kickstand. Should a gecko fall with its back to the ground, a swing of its tail induces the most rapid, zero-angular momentum air-righting response yet measured. Once righted to a sprawled gliding posture, circular tail movements control yaw and pitch as the gecko descends. Our results suggest that large, active tails can function as effective control appendages. These results have provided biological inspiration for the design of an active tail on a climbing robot, and we anticipate their use in small, unmanned gliding vehicles and multisegment spacecraft. PMID:18347344

Jusufi, Ardian; Goldman, Daniel I; Revzen, Shai; Full, Robert J

2008-03-17

214

The human tail and spinal dysraphism.  

PubMed

Recent publications have endeavoured to differentiate between the true, or vestigial tail, and the pseudotail by clinical and pathological examination, and have indicated the benign nature of the true tail. The true tail arises from the most distal remnant of the embryonic tail, contains adipose, connective, muscle, and nerve tissue, and is covered by skin. Pseudotails represent a variety of lesions having in common a lumbosacral protrusion and a superficial resemblance to vestigial tails. A review of the case reports indicates spina bifida to be the most frequent coexisting anomaly with both. A review of occult spinal dysraphism shows it to be associated with cutaneous signs in more than 50% of instances. Three cases of spinal dysraphism with tail-like cutaneous structures are described and their radiological, operative, and pathological findings presented. The classification of each of the appendages into true tail or pseudotail remains obscure. Although the finding of these three tails was the subject of much curiosity, surgical treatment was clearly designed to adequately deal with the associated dysraphic state. The presence of a tail-like appendage in the lumbosacral region should alert the clinician to the possibility of underlying spinal dysraphism. Preoperative assessment must include a complete neurological history and examination as well as computed tomographic or magnetic resonance imaging. PMID:1779337

Belzberg, A J; Myles, S T; Trevenen, C L

1991-10-01

215

Ecotechnological approach for consolidation of uranium tailings.  

PubMed

Present study has been undertaken to consolidate radioactivity in uranium mill tailings at Jaduguda, Jharkhand, India.Tailings that remain after processing of ore are released in tailing ponds specially designed for the purpose. The degraded tailing ponds have been capped with 30 cm. thick soil cover. For cosolidation of radioactivity in the tailings firstly the selected plant species should not have any socioeconomic relevance in that area and secondly, uptake of uranium by selected plants has to be low to avoid its dissemination in any form in environment. Seven native plant species of forestry origin were used for experimental trials. Above ground growth has been measured for two years under ex- situ and in- situ conditions. Distribution and concentration of uranium have been evaluated in tailing pond soil as well as tailings. Uranium uptake by plants has been evaluated and discussed in this paper. The highest concentration of uranium has been found in the order as: in tailings > soil cover on tailings > roots of selected plant species > shoots of all the selected species. These results show that among seven species tried Jatropha gossypifolia and Furcraea foetida have lowest uptake (below detectable limit), while Saccharum spontaneum and Pogostemon benghalense have comparatively higher uptake among the studied species. PMID:23029938

Soni, Prafulla; Singh, Lal

2011-07-01

216

The C-terminal unique region of desmoglein 2 inhibits its internalization via tail-tail interactions  

PubMed Central

Desmosomal cadherins, desmogleins (Dsgs) and desmocollins, make up the adhesive core of intercellular junctions called desmosomes. A critical determinant of epithelial adhesive strength is the level and organization of desmosomal cadherins on the cell surface. The Dsg subclass of desmosomal cadherins contains a C-terminal unique region (Dsg unique region [DUR]) with unknown function. In this paper, we show that the DUR of Dsg2 stabilized Dsg2 at the cell surface by inhibiting its internalization and promoted strong intercellular adhesion. DUR also facilitated Dsg tail–tail interactions. Forced dimerization of a Dsg2 tail lacking the DUR led to decreased internalization, supporting the conclusion that these two functions of the DUR are mechanistically linked. We also show that a Dsg2 mutant, V977fsX1006, identified in arrhythmogenic right ventricular cardiomyopathy patients, led to a loss of Dsg2 tail self-association and underwent rapid endocytosis in cardiac muscle cells. Our observations illustrate a new mechanism desmosomal cadherins use to control their surface levels, a key factor in determining their adhesion and signaling roles.

Chen, Jing; Nekrasova, Oxana E.; Patel, Dipal M.; Klessner, Jodi L.; Godsel, Lisa M.; Koetsier, Jennifer L.; Amargo, Evangeline V.; Desai, Bhushan V.

2012-01-01

217

Recommended Sampling Strategies for Spatial Evaluation of Windblown Contamination Around Uranium Tailings Piles.  

National Technical Information Service (NTIS)

Spatially-distributed 226Ra concentrations measured in soil were statistically analyzed using Kriging to determine an optimum soil sampling strategy for detecting and delineating uranium mill tailings spread from storage piles by wind. A two-stage samplin...

V. W. Thomas R. R. Kinnison

1983-01-01

218

MESSENGER Observations of Extreme Loading and Unloading of Mercury’s Magnetic Tail  

NASA Astrophysics Data System (ADS)

During MESSENGER’s third flyby of Mercury, the magnetic field in the planet’s magnetic tail increased by factors of 2 to 3.5 over intervals of 2 to 3 minutes. Magnetospheric substorms at Earth are powered by similar tail loading, but the amplitude is lower by a factor of ~10 and typical durations are ~1 hour. The extreme tail loading observed at Mercury implies that the relative intensity of substorms must be much larger than at Earth. The correspondence between the duration of tail field enhancements and the characteristic time for the Dungey cycle, which describes plasma circulation through Mercury’s magnetosphere, suggests that such circulation determines the substorm time scale. A key aspect of tail unloading during terrestrial substorms is the acceleration of energetic charged particles, but no acceleration signatures were seen during the MESSENGER flyby.

Slavin, James A.; Anderson, Brian J.; Baker, Daniel N.; Benna, Mehdi; Boardsen, Scott A.; Gloeckler, George; Gold, Robert E.; Ho, George C.; Korth, Haje; Krimigis, Stamatios M.; McNutt, Ralph L.; Nittler, Larry R.; Raines, Jim M.; Sarantos, Menelaos; Schriver, David; Solomon, Sean C.; Starr, Richard D.; Trávní?ek, Pavel M.; Zurbuchen, Thomas H.

2010-08-01

219

MESSENGER observations of extreme loading and unloading of Mercury's magnetic tail.  

PubMed

During MESSENGER's third flyby of Mercury, the magnetic field in the planet's magnetic tail increased by factors of 2 to 3.5 over intervals of 2 to 3 minutes. Magnetospheric substorms at Earth are powered by similar tail loading, but the amplitude is lower by a factor of approximately 10 and typical durations are approximately 1 hour. The extreme tail loading observed at Mercury implies that the relative intensity of substorms must be much larger than at Earth. The correspondence between the duration of tail field enhancements and the characteristic time for the Dungey cycle, which describes plasma circulation through Mercury's magnetosphere, suggests that such circulation determines the substorm time scale. A key aspect of tail unloading during terrestrial substorms is the acceleration of energetic charged particles, but no acceleration signatures were seen during the MESSENGER flyby. PMID:20647422

Slavin, James A; Anderson, Brian J; Baker, Daniel N; Benna, Mehdi; Boardsen, Scott A; Gloeckler, George; Gold, Robert E; Ho, George C; Korth, Haje; Krimigis, Stamatios M; McNutt, Ralph L; Nittler, Larry R; Raines, Jim M; Sarantos, Menelaos; Schriver, David; Solomon, Sean C; Starr, Richard D; Trávnícek, Pavel M; Zurbuchen, Thomas H

2010-07-15

220

Groundwater leaching of neutralized and untreated acid-leached uranium-mill tailings  

SciTech Connect

Tailings neutralization was examined to determine the effect of neutralization on contaminant release. Column leaching of acid extracted uranium mill tailings from Exxon Highland Mill, Wyoming, Pathfinder Gas Hills Mill, Wyoming, and the Dawn Midnite Mill, Washington, resulted in the flushing of high concentrations of salts in the first four pore volumes of leachate, followed by a steady decrease to the original groundwater salt concentrations. Neutralization decreased the concentration of salts and radionuclides leaching from the tailings and decreased the volume of solution required to return the solution to the groundwater pH and EC. Radium-226 and uranium-238 leached quickly from the tailings in the initial pore volumes of both neutralized and unneutralized tailings, and then decreased significantly. 6 figures, 5 tables.

Gee, G.W. (Pacific Northwest Lab., Richland, WA); Begej, C.W.; Campbell, A.C.; Sauter, N.N.; Opitz, B.E.; Sherwood, D.R.

1981-01-01

221

Utilization of spent mushroom compost for the revegetation of lead-zinc tailings: effects on physico-chemical properties of tailings and growth of Lolium perenne.  

PubMed

In an attempt to promote sustainable vegetation cover on metalliferous tailings, a randomized factorial greenhouse trial of six-month duration was established to determine the effect of spent mushroom compost (SMC) amendment on the physical and chemical properties of the predominantly lead/zinc tailings. The tailings originated from the surface (20-30cm) of the partially-vegetated 76ha tailings management facility (TMF), where more than nine million tonnes of pyritic metalliferous material were deposited in an unlined land impoundment. SMC was incorporated at application rates of 0, 50, 100, 200 and 400tonha(-1), with each treatment replicated 10 times and Lolium perenne sown at a rate of 200kgha(-1). The addition of SMC was beneficent as a growing medium through improvement of the structural status of the tailings and ultimately through the provision of plant nutrients and reduction in metal concentrations. However, this improvement in the structural and chemical status of the tailings is not adequate in maintaining a sustainable vegetation cover and therefore other remedial options such as introducing a capillary break on the surface of the tailings facility are necessary. PMID:18501597

Jordan, S N; Mullen, G J; Courtney, R G

2008-05-22

222

Directionality in protein translocation across membranes: the N-tail phenomenon  

Microsoft Academic Search

Protein translocation normally starts from an N-terminal signal peptide and proceeds in an N-to-C-terminal direction. However, in certain integral membrane proteins an N-terminal tail is translocated even though it is not preceded by a signal peptide. In eukaryotic cells this process involves the normal Sec-machinery. In contrast, recent studies in Escherichia coli show that translocation of such N-terminal tails occurs

Ross E. Dalby; Andreas Kuhn; Gunnar von Heijne

1995-01-01

223

Scar-free wound healing and regeneration following tail loss in the leopard gecko, Eublepharis macularius.  

PubMed

Many lizards are able to undergo scar-free wound healing and regeneration following loss of the tail. In most instances, lizard tail loss is facilitated by autotomy, an evolved mechanism that permits the tail to be self-detached at pre-existing fracture planes. However, it has also been reported that the tail can regenerate following surgical amputation outside the fracture plane. In this study, we used the leopard gecko, Eublepharis macularius, to investigate and compare wound healing and regeneration following autotomy at a fracture plane and amputation outside the fracture plane. Both forms of tail loss undergo a nearly identical sequence of events leading to scar-free wound healing and regeneration. Early wound healing is characterized by transient myofibroblasts and the formation of a highly proliferative wound epithelium immunoreactive for the wound keratin marker WE6. The new tail forms from what is commonly referred to as a blastema, a mass of proliferating mesenchymal-like cells. Blastema cells express the protease matrix metalloproteinase-9. Apoptosis (demonstrated by activated caspase 3 immunostaining) is largely restricted to isolated cells of the original and regenerating tail tissues, although cell death also occurs within dermal structures at the original-regenerated tissue interface and among clusters of newly formed myocytes. Furthermore, the autotomized tail is unique in demonstrating apoptosis among cells adjacent to the fracture planes. Unlike mammals, transforming growth factor-?3 is not involved in wound healing. We demonstrate that scar-free wound healing and regeneration are intrinsic properties of the tail, unrelated to the location or mode of tail detachment. PMID:22933425

Delorme, Stephanie Lynn; Lungu, Ilinca Mihaela; Vickaryous, Matthew Kenneth

2012-08-29

224

Identification of Tail Genes in the Temperate Phage 16-3 of Sinorhizobium meliloti 41 ?  

PubMed Central

Genes encoding the tail proteins of the temperate phage 16-3 of the symbiotic nitrogen-fixing bacterium Sinorhizobium meliloti 41 have been identified. First, a new host range gene, designated hII, was localized by using missense mutations. The corresponding protein was shown to be identical to the 85-kDa tail protein by determining its N-terminal sequence. Electron microscopic analysis showed that phage 16-3 possesses an icosahedral head and a long, noncontractile tail characteristic of the Siphoviridae. By using a lysogenic S. meliloti 41 strain, mutants with insertions in the putative tail region of the genome were constructed and virion morphology was examined after induction of the lytic cycle. Insertions in ORF017, ORF018a, ORF020, ORF021, the previously described h gene, and hII resulted in uninfectious head particles lacking tail structures, suggesting that the majority of the genes in this region are essential for tail formation. By using different bacterial mutants, it was also shown that not only the RkpM and RkpY proteins but also the RkpZ protein of the host takes part in the formation of the phage receptor. Results for the host range phage mutants and the receptor mutant bacteria suggest that the HII tail protein interacts with the capsular polysaccharide of the host and that the tail protein encoded by the original h gene recognizes a proteinaceous receptor.

Deak, Veronika; Lukacs, Rita; Buzas, Zsuzsanna; Palvolgyi, Adrienn; Papp, Peter P.; Orosz, Laszlo; Putnoky, Peter

2010-01-01

225

Transmission of bovine viral diarrhea virus among white-tailed deer (Odocoileus virginianus)  

PubMed Central

Cattle persistently infected (PI) with bovine viral diarrhea virus (BVDV), a pestivirus in the family Flaviviridae, are an important source of viral transmission to susceptible hosts. Persistent BVDV infections have been identified in white-tailed deer (Odocoileus virginianus), the most abundant free-ranging ruminant in North America. As PI deer shed BVDV similarly to PI cattle, maintenance of BVDV within white-tailed deer populations may be possible. To date, intraspecific transmission of BVDV in white-tailed deer has not been evaluated, which prompted this study. Six pregnant white-tailed deer were captured in the first trimester of pregnancy and cohabitated with a PI white-tailed deer. Cohabitation with the PI deer resulted in BVDV infection in all does, as indicated by seroconversion. All does gave birth to live fawns and no reproductive losses were observed. At birth, evidence of BVDV infection was identified in two singlet fawns, of which one was determined to be PI by repeated serum reverse transcription nested PCR, whole blood virus isolation and immunohistochemistry. This study demonstrates for the first time that BVDV transmission may occur among white-tailed deer. The birth of a PI fawn through contact to a PI white-tailed deer indicates that under appropriate circumstances, BVDV may be maintained in white-tailed deer by congenital infection.

Passler, Thomas; Ditchkoff, Stephen S.; Givens, M. Daniel; Brock, Kenny V.; DeYoung, Randy W.; Walz, Paul H.

2009-01-01

226

An experimental study of concurrent methods for adaptively controlling vertical tail buffet in high performance aircraft  

NASA Astrophysics Data System (ADS)

High performance twin-tail aircraft, like the F-15 and F/A-18, encounter a condition known as tail buffet. At high angles of attack, vortices are generated at the wing fuselage interface (shoulder) or other leading edge extensions. These vortices are directed toward the twin vertical tails. When the flow interacts with the vertical tail it creates pressure variations that can oscillate the vertical tail assembly. This results in fatigue cracks in the vertical tail assembly that can decrease the fatigue life and increase maintenance costs. Recently, an offset piezoceramic stack actuator was used on an F-15 wind tunnel model to control buffet induced vibrations at high angles of attack. The controller was based on the acceleration feedback control methods, In this thesis a procedure for designing the offset piezoceramic stack actuators is developed. This design procedure includes determining the quantity and type of piezoceramic stacks used in these actuators. The changes of stresses, in the vertical tail caused by these actuators during an active control, are investigated. In many cases, linear controllers are very effective in reducing vibrations. However, during flight, the natural frequencies of the vertical tail structural system changes as the airspeed increases. This in turn, reduces the effectiveness of a linear controller. Other causes such as the unmodeled dynamics and nonlinear effects due to debonds also reduce the effectiveness of linear controllers. In this thesis, an adaptive neural network is used to augment the linear controller to correct these effects.

Roberts, Patrick J.

227

Engineering assessment of inactive uranium mill tailings: Monument Valley Site, Monument Valley, Arizona  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevalated the Monument Valley site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Monument Valley, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposure of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.1 million tons of tailings at the Monument Valley site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through IV). Cost estimates for the four options range from about $6,600,000 for stabilization in-place, to about $15,900,000 for disposal at a distance of about 15 mi. Three principal alternatives for reprocessing the Monument Valley tailings were examined: heap leaching; Treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovery is economically unattractive.

Not Available

1981-10-01

228

A generalized female bias for long tails in a short-tailed widowbird.  

PubMed Central

Tail elongation in the polygynous widowbirds (Euplectes spp.) has evoked both adaptive and non-adaptive explanations. Female choice has been shown in the three longest tailed species (20-50 cm), whereas an agonistic function was proposed for a medium-tailed (10 cm) widowbird. To test the generality and directionality of sexual selection on tail length in widowbirds, we experimentally investigated selection in the relatively short-tailed (7 cm) red-shouldered widowbirds (E. axillaris). Prior to territory establishment, males were assigned to four tail-treatment groups; control, short, long and supernormal (similar to a sympatric long-tailed congener). No effects on male competition were detected as the groups were equally successful in acquiring territories of similar size and quality. However, mating success among the 92 territorial males was strongly skewed in favour of supernormal-tailed males (62% of active nests; 5.2 +/- 1.3 nests per territory). Long-tailed males also acquired more nests (1.9 +/- 0.7) than control (0.7 +/- 0.5) and short-tailed (0.5 +/- 0.3) males, while the latter two groups did not differ significantly. These results support a general, open-ended female preference for long tails in widowbirds and may represent a receiver bias that arose early in their divergence from the short-tailed weaverbirds (Ploceinae).

Pryke, Sarah R; Andersson, Staffan

2002-01-01

229

Mine tailings integrated investigations: The case of Rio tailings (Panasqueira Mine, Central Portugal)  

Microsoft Academic Search

Mining generates huge quantities of waste materials from ore extraction and milling operations, which accumulate in tailings and open impoundments. The risks associated with mine tailings have different nature, namely stability, rupture, surface and groundwater contamination, acid mine drainage (AMD) and precipitation of secondary minerals. In fact catastrophic failure of tailings impoundments has occurred, transporting slurry, dissolved metals and fine

C. Grangeia; P. Ávila; M. Matias; E. Ferreira da Silva

2011-01-01

230

226Ra bioavailability to plants at the Urgeiriça uranium mill tailings site.  

PubMed

Large amounts of solid wastes (tailings) resulting from the exploitation and treatment of uranium ore at the Urgeiriça mine (north of Portugal) have been accumulated in dams (tailing ponds). To reduce the dispersion of natural radionuclides into the environment, some dams were revegetated with eucalyptus (Eucalyptus globolus) and pines (Pinus pinea). Besides these plants, some shrubs (Cytisus spp.) are growing in some of the dams. The objective of this study is to determine the 226Ra bioavailability from uranium mill tailings by quantifying the total and available fraction of radium in the tailings and to estimate its transfer to plants growing on the tailing piles. Plant and tailing samples were randomly collected and the activity concentration of 226Ra in plants (aerial part and roots) and tailings was measured by gamma-spectrometry. The exchangeable fraction of radium in tailings was quantified using one single step extraction with 1 mol dm-3 ammonium acetate (pH = 7) or 1 mol dm-3 calcium chloride solutions. The results obtained for 226Ra uptake by plants show that 226Ra concentration ratios for eucalyptus and pines decrease at low 226Ra concentrations in the tailings and appear relatively constant at higher radium concentrations. For shrubs, the concentration ratios increase at higher 226Ra solid waste concentrations approaching a saturation value. Percentage values of 16.0 +/- 8.3 and 12.9 +/- 8.9, for the fraction of radium extracted from the tailings, using 1 mol dm-3 ammonium acetate or calcium chloride solutions, respectively, were obtained. The 226Ra concentration ratios determined on the basis of exchangeable radium are one order of magnitude higher than those based on total radium. It can be concluded that, at a 95% confidence level, more consistent 226Ra concentration ratios were obtained when calculated on the basis of available radium than when total radium was considered, for all the dams. PMID:11379070

Madruga, M J; Brogueira, A; Alberto, G; Cardoso, F

2001-01-01

231

Investigation of contamination of earthen covers on inactive uranium mill tailings  

SciTech Connect

The upward migration of contaminants into earthen covers on uranium mill tailings was evaluated from chemical and isotopic analysis of samples from 5--10 cm intervals through the cover and into the tailings at three locations on the Riverton pile. The Uranium Mill Tailings Remedial Action Project elected to determine the significance of migration of salts and contaminants into earthen covers emplaced on tailings by funding this investigation of the migration which has occurred through an earthen cover since the time of emplacement on an inactive uranium mill tailings pile. The Riverton tailings pile, covered with 20 to 40 cm of local sandy soil, was chosen for the study. The objectives of the study were to: determine vertical distributions of concentrations of salts, trace metals, and radionuclides through the cover and into the tailings; determine the concentrations of salts and contaminants in the cover from chemical migration; relate the migration of salts to the contaminants; model the mechanisms responsible for promoting and retarding migration; and evaluate the chemical and physical properties of the cover influencing migration. 20 refs., 35 figs., 10 tabs.

Markos, G.; Bush, K.J.

1983-01-01

232

RICO Graduate Student Research Flight: The Island Tail Objective  

NASA Astrophysics Data System (ADS)

The Rain in Cumulus over the Ocean (RICO) project was an intensive field project aimed to study and understand precipitation processes in trade wind cumulus. The project took place from Nov 23, 2004 until Jan 25, 2005 on two small islands of the Lesser Antilles, Antigua and Barbuda, where trade wind cumulus fields frequently occur during suppressed wintertime conditions. RICO provided a unique combination of research and education by offering the RICO Graduate Seminar Series and the development and implementation of a graduate student designed and directed research flight. One of the main goals of the graduate student research flight was to allow graduate students to participate in the process of developing a research flight plan and identifying scientific goals and objectives first-hand. Added benefits included the possibility of addressing scientific questions not included in the main RICO objectives. This also involved collaboration when discussing different ideas and initiatives and the full development of all stages of the research flight including the coordination of two research aircraft (NCAR-C130, University of Wyoming King Air), one research vessel (RV Seward Johnson), S-Pol radar site and real time operations center satellite information. Seventeen graduate students from both the US and Europe developed two different plans to be presented to RICO project principle investigators; both of which were approved. The island tail objective aimed at characterizing the line of clouds known as 'island tails' that frequently form off the leeward coast of the Caribbean islands. This objective was successful in its implementation on Jan 18, 2005 with measurements made in vigorous, waterspout producing tail clouds immediately downwind of Barbuda. The investigation of these 'tails' fills a void in current cloud physics research since it is the first time this ubiquitous feature of trade-wind islands has been the focus of careful study. Scientific questions to be addressed with data collected on the island tail include: 1) Are these clouds forced by a heated island effect or another dynamical mechanism? 2) Do islands serve merely as source regions of aerosol which act as nucleation sites? 3) Where in the island tail does rain develop, if at all? A description of the unique learning experience and the educational and scientific benefits of the graduate student research flight island tail objective are outlined and discussed.

Small, J. D.; Anderson-Bereznicki, S. D.; Medeiros, B.; Nuijens, L.; Henry, C. K.; O'Donnell, D. M.; Morales, F.; Shen, H.

2005-12-01

233

Novel plant SUN-KASH bridges are involved in RanGAP anchoring and nuclear shape determination.  

PubMed

Inner nuclear membrane Sad1/UNC-84 (SUN) proteins interact with outer nuclear membrane (ONM) Klarsicht/ANC-1/Syne homology (KASH) proteins, forming linkers of nucleoskeleton to cytoskeleton conserved from yeast to human and involved in positioning of nuclei and chromosomes. Defects in SUN-KASH bridges are linked to muscular dystrophy, progeria, and cancer. SUN proteins were recently identified in plants, but their ONM KASH partners are unknown. Arabidopsis WPP domain-interacting proteins (AtWIPs) are plant-specific ONM proteins that redundantly anchor Arabidopsis RanGTPase-activating protein 1 (AtRanGAP1) to the nuclear envelope (NE). In this paper, we report that AtWIPs are plant-specific KASH proteins interacting with Arabidopsis SUN proteins (AtSUNs). The interaction is required for both AtWIP1 and AtRanGAP1 NE localization. AtWIPs and AtSUNs are necessary for maintaining the elongated nuclear shape of Arabidopsis epidermal cells. Together, our data identify the first KASH members in the plant kingdom and provide a novel function of SUN-KASH complexes, suggesting that a functionally diverged SUN-KASH bridge is conserved beyond the opisthokonts. PMID:22270916

Zhou, Xiao; Graumann, Katja; Evans, David E; Meier, Iris

2012-01-23

234

Novel plant SUN-KASH bridges are involved in RanGAP anchoring and nuclear shape determination  

PubMed Central

Inner nuclear membrane Sad1/UNC-84 (SUN) proteins interact with outer nuclear membrane (ONM) Klarsicht/ANC-1/Syne homology (KASH) proteins, forming linkers of nucleoskeleton to cytoskeleton conserved from yeast to human and involved in positioning of nuclei and chromosomes. Defects in SUN–KASH bridges are linked to muscular dystrophy, progeria, and cancer. SUN proteins were recently identified in plants, but their ONM KASH partners are unknown. Arabidopsis WPP domain–interacting proteins (AtWIPs) are plant-specific ONM proteins that redundantly anchor Arabidopsis RanGTPase–activating protein 1 (AtRanGAP1) to the nuclear envelope (NE). In this paper, we report that AtWIPs are plant-specific KASH proteins interacting with Arabidopsis SUN proteins (AtSUNs). The interaction is required for both AtWIP1 and AtRanGAP1 NE localization. AtWIPs and AtSUNs are necessary for maintaining the elongated nuclear shape of Arabidopsis epidermal cells. Together, our data identify the first KASH members in the plant kingdom and provide a novel function of SUN–KASH complexes, suggesting that a functionally diverged SUN–KASH bridge is conserved beyond the opisthokonts.

Zhou, Xiao; Graumann, Katja; Evans, David E.

2012-01-01

235

Using comet plasma tails to study the solar wind  

NASA Astrophysics Data System (ADS)

The plasma tails of comets have been used as probes of the solar wind for many years, and well before direct solar wind measurements. Now, analyses utilizing the much greater regularity and extent of comet tails imaged from space detail outward solar wind flow much better than was previously possible. These analyses mark the location of the solar wind flow in three-dimensions over time much as do in-situ measurements. Data from comet plasma tails using coronagraphs and heliospheric white-light imagers provide a view closer to the Sun than where spacecraft have ventured to date. These views show that this flow is chaotic and highly variable, and not the benign regular outward motion of a quiescent plasma. While this is no surprise to those who study and characterize the solar wind in situ or use remotely-sensed interplanetary scintillation (IPS) techniques, these spacecraft images provide a visualization of this as never-before possible. Here we summarize the results of an analysis that determines solar wind velocity from multiple comet tails that were observed by the Solar Mass Ejection Imager (SMEI) and also by the inner Heliospheric Imager (HI) on board the Solar Terrestrial Relations Observatory Ahead (STEREOA) spacecraft. Finally, we present results using a similar analysis that measures this same behavior using coronagraph observations in the low corona.

Jackson, B. V.; Buffington, A.; Clover, J. M.; Hick, P. P.; Yu, H.-S.; Bisi, M. M.

2013-06-01

236

Effectiveness of Spayvac for reducing white-tailed deer fertility.  

PubMed

Overabundant white-tailed deer (Odocoileus virginianus) populations have been reported in many urban and suburban communities across the United States. Large populations of deer can potentially increase the risk of human-wildlife conflicts, such as deer-vehicle collisions, transmission of disease to humans, and vegetation damage. In 2003, efforts to control white-tailed deer numbers were initiated at the National Aeronautical and Space Agency's (NASA) Lyndon B. Johnson Space Center (JSC) in Houston, Texas, using the long-lasting, single-dose contraceptive SpayVac. Our objectives were to evaluate the effectiveness of SpayVac for reducing white-tailed deer fertility and determine the partial cost for treatment. Between 2003 and 2004, we monitored 45 adult female deer (34 treated with SpayVac, 11 controls treated with a placebo). Fawning rate over 2 yr for deer treated with SpayVac >30 days prior to the rut was 0% (n=31), whereas the fawning rate for control deer was 78% (n=11). Inoculation 1 mo prior to the breeding season was sufficient time to achieve fertility control. We conclude that SpayVac can effectively reduce the fertility of urban white-tailed deer. PMID:17984269

Locke, Shawn L; Cook, Matthew W; Harveson, Louis A; Davis, Donald S; Lopez, Roel R; Silvy, Nova J; Fraker, Mark A

2007-10-01

237

Prenatal Diagnosis of ‘True Tail’ with Cartilage Content?  

Microsoft Academic Search

A human tail is a rare congenital anomaly with a prominent lesion from the lumbosacrococcygeal region. According to Dao and Netzky human tails are classified into ‘true tails’ and ‘pseudotails’. True tails comprise only mesenchymal tissue (adipose, connective, muscle, nerve tissue, blood vessels, and cutis). They are presumed to be remnants of the embryologic tail. All other lumbosacrococcygeal protrusions are

Frank Noack; Erich Reusche; Ulrich Gembruch

2003-01-01

238

Comet tail formation: Giotto observations  

SciTech Connect

The process of mass loading of the solar wind by cometary ions, which forms comet tails, has been observed throughout the coma of comet Halley. Three distinct regimes were found where the nature of the energy and momentum coupling between solar wind and cometary ions is different. Outside the bow shock, where there is little angular scattering of the freshly ionized particles, the coupling is described by the simple pickup trajectory and the energy is controlled by the angle between the flow and the magnetic field. Just inside the bow shock, there is considerable scattering accompanied by another acceleration process which raises some particle energies well above the straightforward pickup value. Finally, closer to the nucleus, the amount of scattering decreases and the coupling is once more controlled by the magnetic field direction. 4 refs., 3 figs.

Wilken, B.; Jockers, K.; Johnstone, A.; Coates, A.; Heath, J.; Formisano, V.; Amata, E.; Winningham, J.D.; Thomsen, M.; Bryant, D.A.

1986-01-01

239

Tail reconnection triggering substorm onset.  

PubMed

Magnetospheric substorms explosively release solar wind energy previously stored in Earth's magnetotail, encompassing the entire magnetosphere and producing spectacular auroral displays. It has been unclear whether a substorm is triggered by a disruption of the electrical current flowing across the near-Earth magnetotail, at approximately 10 R(E) (R(E): Earth radius, or 6374 kilometers), or by the process of magnetic reconnection typically seen farther out in the magnetotail, at approximately 20 to 30 R(E). We report on simultaneous measurements in the magnetotail at multiple distances, at the time of substorm onset. Reconnection was observed at 20 R(E), at least 1.5 minutes before auroral intensification, at least 2 minutes before substorm expansion, and about 3 minutes before near-Earth current disruption. These results demonstrate that substorms are likely initiated by tail reconnection. PMID:18653845

Angelopoulos, Vassilis; McFadden, James P; Larson, Davin; Carlson, Charles W; Mende, Stephen B; Frey, Harald; Phan, Tai; Sibeck, David G; Glassmeier, Karl-Heinz; Auster, Uli; Donovan, Eric; Mann, Ian R; Rae, I Jonathan; Russell, Christopher T; Runov, Andrei; Zhou, Xu-Zhi; Kepko, Larry

2008-07-24

240

Identification of Regions Interacting with Ovo(d) Mutations: Potential New Genes Involved in Germline Sex Determination or Differentiation in Drosophila Melanogaster  

PubMed Central

Only a few Drosophila melanogaster germline sex determination genes are known, and there have been no systematic screens to identify new genes involved in this important biological process. The ovarian phenotypes produced by females mutant for dominant alleles of the ovo gene are modified in flies with altered doses of other loci involved in germline sex determination in Drosophila (Sex-lethal(+), sans fille(+) and ovarian tumor(+)). This observation constitutes the basis for a screen to identify additional genes required for proper establishment of germline sexual identity. We tested 300 deletions, which together cover ~58% of the euchromatic portion of the genome, for genetic interactions with ovo(D). Hemizygosity for more than a dozen small regions show interactions that either partially suppress or enhance the ovarian phenotypes of females mutant for one or more of the three dominant ovo mutations. These regions probably contain genes whose products act in developmental hierarchies that include ovo(+) protein.

Pauli, D.; Oliver, B.; Mahowald, A. P.

1995-01-01

241

DNA sequences of the tail fiber genes of bacteriophage P2: evidence for horizontal transfer of tail fiber genes among unrelated bacteriophages.  

PubMed

We have determined the DNA sequence of the bacteriophage P2 tail genes G and H, which code for polypeptides of 175 and 669 residues, respectively. Gene H probably codes for the distal part of the P2 tail fiber, since the deduced sequence of its product contains regions similar to tail fiber proteins from phages Mu, P1, lambda, K3, and T2. The similarities of the carboxy-terminal portions of the P2, Mu, ann P1 tail fiber proteins may explain the observation that these phages in general have the same host range. The P2 H gene product is similar to the products of both lambda open reading frame (ORF) 401 (stf, side tail fiber) and its downstream ORF, ORF 314. If 1 bp is inserted near the end of ORF 401, this reading frame becomes fused with ORF 314, creating an ORF that may represent the complete stf gene that encodes a 774-amino-acid-long side tail fiber protein. Thus, a frameshift mutation seems to be present in the common laboratory strain of lambda. Gene G of P2 probably codes for a protein required for assembly of the tail fibers of the virion. The entire G gene product is very similar to the products of genes U and U' of phage Mu; a region of these proteins is also found in the tail fiber assembly proteins of phages TuIa, TuIb, T4, and lambda. The similarities in the tail fiber genes of phages of different families provide evidence that illegitimate recombination occurs at previously unappreciated levels and that phages are taking advantage of the gene pool available to them to alter their host ranges under selective pressures. PMID:1531648

Haggård-Ljungquist, E; Halling, C; Calendar, R

1992-03-01

242

DNA sequences of the tail fiber genes of bacteriophage P2: evidence for horizontal transfer of tail fiber genes among unrelated bacteriophages.  

PubMed Central

We have determined the DNA sequence of the bacteriophage P2 tail genes G and H, which code for polypeptides of 175 and 669 residues, respectively. Gene H probably codes for the distal part of the P2 tail fiber, since the deduced sequence of its product contains regions similar to tail fiber proteins from phages Mu, P1, lambda, K3, and T2. The similarities of the carboxy-terminal portions of the P2, Mu, ann P1 tail fiber proteins may explain the observation that these phages in general have the same host range. The P2 H gene product is similar to the products of both lambda open reading frame (ORF) 401 (stf, side tail fiber) and its downstream ORF, ORF 314. If 1 bp is inserted near the end of ORF 401, this reading frame becomes fused with ORF 314, creating an ORF that may represent the complete stf gene that encodes a 774-amino-acid-long side tail fiber protein. Thus, a frameshift mutation seems to be present in the common laboratory strain of lambda. Gene G of P2 probably codes for a protein required for assembly of the tail fibers of the virion. The entire G gene product is very similar to the products of genes U and U' of phage Mu; a region of these proteins is also found in the tail fiber assembly proteins of phages TuIa, TuIb, T4, and lambda. The similarities in the tail fiber genes of phages of different families provide evidence that illegitimate recombination occurs at previously unappreciated levels and that phages are taking advantage of the gene pool available to them to alter their host ranges under selective pressures.

Haggard-Ljungquist, E; Halling, C; Calendar, R

1992-01-01

243

Uranium Mill Tailings Remedial Action Project (UMTRAP) Public Participation Plan  

SciTech Connect

The purpose of this Public Participation Plan is to explain the Department of Energy`s plan for involving the public in the decision-making process related to the Uranium Mill Tailings Remedial Action (UMTRA) Project. This project was authorized by Congress in the Uranium Mill Tailings Radiation Control Act of 1978. The Act provides for a cooperative effort with affected states and Indian tribes for the eventual cleanup of abandoned or inactive uranium mill tailings sites, which are located in nine western states and in Pennsylvania. Section 111 of the Act states, ``in carrying out the provisions of this title, including the designation of processing sites, establishing priorities for such sites, the selection of remedial actions and the execution of cooperative agreements, the Secretary (of Energy), the Administrator (of the Environmental Protection Agency), and the (Nuclear Regulatory) Commission shall encourage public participation and, where appropriate, the Secretary shall hold public hearings relative to such matters in the States where processing sites and disposal sites are located.`` The objective of this document is to show when, where, and how the public will be involved in this project.

NONE

1981-05-01

244

The histone tails of the nucleosome  

Microsoft Academic Search

Reversible acetylation of core histone tails plays an important role in the regulation of eukaryotic transcription, in the formation of repressive chromatin complexes, and in the inactivation of whole chromosomes. The high-resolution X-ray structure of the nucleosome core particle, as well as earlier evidence, suggests that the histone tails are largely responsible for the assembly of nucleosomes into chromatin fibers

Karolin Luger; Timothy J Richmond

1998-01-01

245

Vertical tail buffeting of fighter aircraft  

Microsoft Academic Search

Vertical tail buffeting at high angles of attack is a phenomenon associated with the impact of vortical flows generated by the aircraft on the fins. This poses a serious problem for both single- and twin-tail fighter aircraft from the point of view of combat maneuverability and structural integrity. The research activities to understand the flow physics with an aim to

B. H. K. Lee

2000-01-01

246

Human Tail: Nature’s Aberration  

Microsoft Academic Search

Human tail refers to a congenital cutaneous appendix protruding from the lumbosacral region. It is usually associated with an underlying spina bifida occulta, a form of spinal dysraphism. A contiguous fibrolipoma can sometimes be seen extending from the subcutaneous portion of the tail into the inferior spinal cord, resulting in tethered cord syndrome. Management of such lesions includes complete neurologic

Dipti Kumar; Akshay Kapoor

2012-01-01

247

Groundwater pollution due to a tailings dam  

Microsoft Academic Search

In 1982, the Oman Mining Company (OMC) commenced copper mining and smelting operations in the area of Sohar (Wadi Suq), Sultanate of Oman. Seawater was used for mining operations until 1993. During this period, 11 million tonnes of tailings had been deposited behind an unlined tailings dam. This has resulted in a major groundwater pollution problem.This paper presents results from

R. S Sharma; T. S Al-Busaidi

2001-01-01

248

MINE TAILINGS DAMS: WHEN THINGS GO WRONG  

Microsoft Academic Search

Mine tailings impoundment failures continue to occur at unacceptable rates. The worldwide mining industry has experienced roughly one significant impoundment failure per year over the past 30 years. Many of these failure events have resulted in massive damage, severe economical impact and, in several cases, loss of life. A tailings impoundment failure case history database has been developed. In addition

Michael Davies; Todd Martin; Peter Lighthall

249

Electrodialytic remediation of copper mine tailings  

Microsoft Academic Search

Mining activities in Chile have generated large amounts of solid waste, which have been deposited in mine tailing impoundments. These impoundments cause concern to the communities due to dam failures or natural leaching to groundwater and rivers.This work shows the laboratory results of nine electrodialytic remediation experiments on copper mine tailings. The results show that electric current could remove copper

Henrik K. Hansen; Adrián Rojo; Lisbeth M. Ottosen

2005-01-01

250

Evidence for a pathogenic determinant in HIV-1 Nef involved in B cell dysfunction in HIV/AIDS  

PubMed Central

SUMMARY B lymphocyte hyperactivation and hypergammaglobulinemia are pathogenic manifestations of HIV-1 infection. Here we provide evidence that these B cell defects are driven by factors produced by HIV-1 infected macrophages and that Nef is necessary for this activity. In vitro, HIV-1 infected macrophages or macrophages expressing Nef promoted B cell activation and differentiation to immunoglobulin-secreting cells. Activation of NF-?B by Nef induced secretion of the acute-phase reactant ferritin and ferritin was necessary and sufficient for these B cell effects. The extent of hypergammaglobulinemia in HIV-1 infected individuals correlated directly with plasma ferritin levels and with viral load. We further demonstrate that induction of ferritin and hypergammaglobulinemia could be recapitulated when Nef was specifically expressed in macrophages and T cells of transgenic mice. Collectively, these results reveal the presence of a pathogenic determinant within the Nef protein of HIV-1 which governs B cell defects in HIV-1 infection.

Swingler, Simon; Zhou, Jin; Swingler, Catherine; Dauphin, Ann; Greenough, Thomas; Jolicoeur, Paul; Stevenson, Mario

2010-01-01

251

Visual acuity in the short-tailed opossum (Monodelphis domestica).  

PubMed

Monodelphis domestica (short-tailed opossum) is an emerging animal model for studies of neural development due to the extremely immature state of the nervous system at birth and its subsequent rapid growth to adulthood. Yet little is known about its normal sensory discrimination abilities. In the present investigation, visual acuity was determined in this species using the optokinetic test (OPT), which relies on involuntary head tracking of a moving stimulus and can be easily elicited using a rotating visual stimulus of varying spatial frequencies. Using this methodology, we determined that the acuity of Monodelphis is 0.58 cycles per degree (cpd), which is similar to the acuity of rats using the same methodology, and higher than in mice. However, acuity in the short-tailed opossum is lower than in other marsupials. This is in part due to the methodology used to determine acuity, but may also be due to differences in diel patterns, lifestyle and phylogeny. We demonstrate that for the short-tailed opossum, the OPT is a rapid and reliable method of determining a baseline acuity and can be used to study enhanced acuities due to cortical plasticity. PMID:22871523

Dooley, J C; Nguyen, H M; Seelke, A M H; Krubitzer, L

2012-08-04

252

The Urbach tail in silica glass from first principles  

SciTech Connect

We present density-functional theory calculations of the optical absorption spectra of silica glass for temperatures up to 2400K. The calculated spectra exhibit exponential tails near the fundamental absorption edge that follow the Urbach rule, in quantitative agreement with experiments. We discuss the accuracy of our results by comparing to hybrid exchange correlation functionals. We derive a simple relationship between the exponential tails of the absorption coefficient and the electronic density-of-states, and thereby establish a direct link between the photoemission and the absorption spectra near the absorption edge. We use this relationship to determine the lower bound to the Urbach frequency regime. We show that in this frequency interval, the optical absorption is Poisson distributed with very large statistical fluctuations. We determine the upper bound to the Urbach frequency regime by identifying the frequency at which transition to Poisson distribution takes place.

Sadigh, B; Erhart, P; Aberg, D; Trave, A; Schwegler, E; Bude, J

2010-06-15

253

[Determination of blood alcohol level of people who are involved in a judicial event of medical importance (case report)].  

PubMed

In some cases, determination of blood alcohol level is very important. The alcohol level at the time of an event, can affect the court decision and may lead to aggravate the penalty or on the contrary an acquittal. In this article, a criminal action, in one of Turkish High Criminal Court is examined. The case was about the death of a drunk person who had fallen down from the window of his girl friend's house which is on the third floor of an apartment. This person's parent applied to public prosecutor saying that their child did not fall down but was murdered by his girl friend. During this trial, in the victim's autopsy, no alcohol detected in blood in contrast with his girl friend's testimony. Because of this contradiction, a reasonable doubt has emerged that she was the murderer in this suspicious death. However, in the further stages of trial, the reasons of no alcohol detection in the autopsy is investigated. In the basis of this case, the importance and techniques of alcohol detection in blood is discussed with literature. PMID:11705087

Alkan, N; Demircan, T

2001-10-01

254

Molecular Determinants within the Surface Proteins Involved in the Pathogenicity of H5N1 Influenza Viruses in Chickens  

PubMed Central

Although it is established that the cleavage site and glycosylation patterns in the hemagglutinin (HA) play important roles in determining the pathogenicity of H5 avian influenza viruses, some viruses exist that are not highly pathogenic despite possessing the known characteristics of high pathogenicity (i.e., their HA contains multiple basic amino acids at the cleavage site and has glycosylation patterns similar to that of the highly pathogenic H5 viruses). Currently little is known about the H5N1 viruses that fall into this intermediate category of pathogenicity. We have identified strains of H5N1 avian influenza viruses that have markers typical of high pathogenicity but distinctly differ in their ability to cause disease and death in chickens. By analyzing viruses constructed by reverse-genetic methods and containing recombinant HAs, we established that amino acids 97, 108, 126, 138, 212, and 217 of HA, in addition to those within the cleavage site, affect pathogenicity. Further investigation revealed that an additional glycosylation site within the neuraminidase (NA) protein globular head contributed to the high virulence of the H5N1 virus. Our findings are in agreement with previous observations that suggest that the activities of the HA and NA proteins are functionally linked.

Hulse, Diane J.; Webster, Robert G.; Russell, Rupert J.; Perez, Daniel R.

2004-01-01

255

The phage ? major tail protein structure reveals a common evolution for long-tailed phages and the type VI bacterial secretion system  

PubMed Central

Most bacteriophages possess long tails, which serve as the conduit for genome delivery. We report the solution structure of the N-terminal domain of gpV, the protein comprising the major portion of the noncontractile phage ? tail tube. This structure is very similar to a previously solved tail tube protein from a contractile-tailed phage, providing the first direct evidence of an evolutionary connection between these 2 distinct types of phage tails. A remarkable structural similarity is also seen to Hcp1, a component of the bacterial type VI secretion system. The hexameric structure of Hcp1 and its ability to form long tubes are strikingly reminiscent of gpV when it is polymerized into a tail tube. These data coupled with other similarities between phage and type VI secretion proteins support an evolutionary relationship between these systems. Using Hcp1 as a model, we propose a polymerization mechanism for gpV involving several disorder-to-order transitions.

Pell, Lisa G.; Kanelis, Voula; Donaldson, Logan W.; Lynne Howell, P.; Davidson, Alan R.

2009-01-01

256

Development and application of a hybrid method involving interpolation and ab initio calculations for the determination of transition states  

NASA Astrophysics Data System (ADS)

Transition state search algorithms, such as the nudged elastic band can fail, if a good initial guess of the transition state structure cannot be provided. The growing string method (GSM) [J. Chem. Phys. 120, 7877 (2004)] eliminates the need for an initial guess of the transition state. While this method only requires knowledge of the reactant and product geometries, it is computationally intensive. To alleviate the bottlenecks in the GSM, several modifications were implemented: Cartesian coordinates were replaced by internal coordinates, the steepest descent method for minimization of orthogonal forces to locate the reaction path was replaced by the conjugate gradient method, and an interpolation scheme was used to estimate the energy and gradient, thereby reducing the calls to the quantum mechanical (QM) code. These modifications were tested to measure the reduction in computational time for four cases of increasing complexity: the Müller-Brown potential energy surface, alanine dipeptide isomerization, H abstraction in methanol oxidation, and C-H bond activation in oxidative carbonylation of toluene to p-toluic acid. These examples show that the modified GSM can achieve two- to threefold speedups (measured in terms of the reduction in actual QM gradients computed) over the original version of the method without compromising accuracy of the geometry and energy of the final transition state. Additional savings in computational effort can be achieved by carrying out the initial search for the minimum energy pathway (MEP) using a lower level of theory (e.g., HF/STO-3G) and then refining the MEP using density functional theory at the B3LYP level with larger basis sets (e.g., 6-31G*, LANL2DZ). Thus, a general strategy for determining transition state structures is to initiate the modified GSM using a low level of theory with minimal basis sets and then refining the calculation at a higher level of theory with larger basis sets.

Goodrow, Anthony; Bell, Alexis T.; Head-Gordon, Martin

2008-11-01

257

Lactation performance of two Iranian fat-tailed sheep breeds  

Microsoft Academic Search

Lactation performance of four- and five-year-old ewes from two fat-tailed Iranian breeds (Mehraban, n = 22; and Ghezel, n = 19), giving birth to single lambs, was studied. Milk production during the suckling period (15 weeks) was determined by a combined lamb-suckling and hand-milking and daily milking from weaning to end of lactation. Average lactation length and milk yield were

J. Izadifard; M. J. Zamiri

1997-01-01

258

Structural Basis for Tail-Anchored Membrane Protein Biogenesis by the Get3-Receptor Complex  

PubMed Central

Tail-anchored (TA) proteins are involved in cellular processes including trafficking, degradation, and apoptosis. They contain a C-terminal membrane anchor and are posttranslationally delivered to the endoplasmic reticulum (ER) membrane by the Get3 adenosine triphosphatase interacting with the hetero-oligomeric Get1/2 receptor. We have determined crystal structures of Get3 in complex with the cytosolic domains of Get1 and Get2 in different functional states at 3.0, 3.2, and 4.6 angstrom resolution. The structural data, together with biochemical experiments, show that Get1 and Get2 use adjacent, partially overlapping binding sites and that both can bind simultaneously to Get3. Docking to the Get1/2 complex allows for conformational changes in Get3 that are required for TA protein insertion. These data suggest a molecular mechanism for nucleotide-regulated delivery of TA proteins.

Stefer, Susanne; Reitz, Simon; Wang, Fei; Wild, Klemens; Pang, Yin-Yuin; Schwarz, Daniel; Bomke, Jorg; Hein, Christopher; Lohr, Frank; Bernhard, Frank; Denic, Vladimir; Dotsch, Volker; Sinning, Irmgard

2013-01-01

259

Structural basis for tail-anchored membrane protein biogenesis by the Get3-receptor complex.  

PubMed

Tail-anchored (TA) proteins are involved in cellular processes including trafficking, degradation, and apoptosis. They contain a C-terminal membrane anchor and are posttranslationally delivered to the endoplasmic reticulum (ER) membrane by the Get3 adenosine triphosphatase interacting with the hetero-oligomeric Get1/2 receptor. We have determined crystal structures of Get3 in complex with the cytosolic domains of Get1 and Get2 in different functional states at 3.0, 3.2, and 4.6 angstrom resolution. The structural data, together with biochemical experiments, show that Get1 and Get2 use adjacent, partially overlapping binding sites and that both can bind simultaneously to Get3. Docking to the Get1/2 complex allows for conformational changes in Get3 that are required for TA protein insertion. These data suggest a molecular mechanism for nucleotide-regulated delivery of TA proteins. PMID:21719644

Stefer, Susanne; Reitz, Simon; Wang, Fei; Wild, Klemens; Pang, Yin-Yuin; Schwarz, Daniel; Bomke, Jörg; Hein, Christopher; Löhr, Frank; Bernhard, Frank; Denic, Vladimir; Dötsch, Volker; Sinning, Irmgard

2011-06-30

260

Determination of alveolar epithelial cell phenotypes in fetal sheep: evidence for the involvement of basal lung expansion  

PubMed Central

The factors that control the differentiation of alveolar epithelial cells (AECs) into type-I and type-II cells in vivo are largely unknown. As sustained increases in fetal lung expansion induce type-II AECs to differentiate into type-I cells, our aim was to determine whether reduced fetal lung expansion can induce type-I AECs to trans-differentiate into type-II AECs. Chronically catheterised fetal sheep were divided into two age-matched control groups and three experimental groups (n = 5 for each). The experimental groups were exposed to either: (1) 10 days of increased lung expansion induced by tracheal obstruction (TO), (2) 10 days of TO followed by 5 days of reduced lung expansion induced by lung liquid drainage (LLD), or (3) 10 days of TO followed by 10 days of LLD. Following 10 days of TO, 5 days of LLD reduced the proportion of type-I AECs from 89.4 ± 0.9 % to 68.4 ± 2.8 %, which was similar to control values (64.8 ± 0.5 %), and increased the proportion of type-II AECs from 1.9 ± 0.3 % to 21.9 ± 2.8 %, which remained below control values (33.4 ± 1.7 %). The same treatment increased surfactant protein (SP)-A, SP-B and SP-C mRNA levels (expressed as a percentage of control values) from 26.7 ± 6.0 %, 40.0 ± 7.3 % and 10.3 ± 1.8 % to 78.1 ± 10.3 %, 105.8 ± 12.7 % and 121.0 ± 14.1 %, respectively. Similar results were obtained after 10 days of LLD, which followed 10 days of TO. These results indicate that the phenotypes of type-I and type-II AECs are strongly influenced by the basal degree of lung expansion in fetal sheep. Furthermore, the coincident increase in type-II AEC proportions and SP mRNA levels in response to LLD suggests that type-I AECs can trans-differentiate into functional type-II cells, and hence are not terminally differentiated.

Flecknoe, Sharon J; Wallace, Megan J; Harding, Richard; Hooper, Stuart B

2002-01-01

261

Improved visualization of the pancreatic tail after maximum distension of the stomach  

SciTech Connect

Fifty-two computed tomography examinations through the region of the pancreas were retrospectively analyzed to determine if marked stomach distension influenced the visualization of the pancreatic tail. Of the 29 patients who had marked stomach distension, 25 (86%) had displacement of small bowel loops away from the ventral surface of the pancreatic tail. With moderate or minimal stomach distension, there was bowel loop displacement in 37% and 0% of cases, respectively. Marked stomach distension appears to be an effective means of improving visualization of the pancreatic tail.

Stuck, K.J.; Kuhns, L.R.

1981-08-01

262

Limiting distributions of continuous-time random walks with superheavy-tailed waiting times  

NASA Astrophysics Data System (ADS)

We study the long-time behavior of the scaled walker (particle) position associated with decoupled continuous-time random walks which is characterized by superheavy-tailed distribution of waiting times and asymmetric heavy-tailed distribution of jump lengths. Both the scaling function and the corresponding limiting probability density are determined for all admissible values of tail indexes describing the jump distribution. To analytically investigate the limiting density function, we derive a number of different representations of this function and, in this way, establish its main properties. We also develop an efficient numerical method for computing the limiting probability density and compare our analytical and numerical results.

Denisov, S. I.; Bystrik, Yu. S.; Kantz, H.

2013-02-01

263

Limiting distributions of continuous-time random walks with superheavy-tailed waiting times.  

PubMed

We study the long-time behavior of the scaled walker (particle) position associated with decoupled continuous-time random walks which is characterized by superheavy-tailed distribution of waiting times and asymmetric heavy-tailed distribution of jump lengths. Both the scaling function and the corresponding limiting probability density are determined for all admissible values of tail indexes describing the jump distribution. To analytically investigate the limiting density function, we derive a number of different representations of this function and, in this way, establish its main properties. We also develop an efficient numerical method for computing the limiting probability density and compare our analytical and numerical results. PMID:23496470

Denisov, S I; Bystrik, Yu S; Kantz, H

2013-02-15

264

Key programmatic steps and activities for implementing the Uranium Mill Tailings Remedial Action Project. [UMTRA Project  

SciTech Connect

The Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA) was enacted based upon findings by Congress that uranium mill tailings located at active and inactive hazard to the public, and that protection of the public health, safety and welfare, and the regulations of interstate commerce, require that every reasonable effort be made to provide for the stabilization, disposal, and control in a safe and environmentally sound manner of such tailings in order to prevent or minimize radon diffusion into the environment and to prevent or minimize other environmental hazards from such tailings.'' A general understanding of the steps leading to elimination of the hazards associated with designated uranium mill tailings sites, and the parties involved in that effort, are presented in this document. A representative schedule is also presented in this document to show both program sequence and activity interdependence. Those activities that have the most potential to influence program duration, because of the significant amount of additional time that may be required, include identification and selection of a suitable site, field data collection delays due to weather, actual acquisition of the designated or alternate disposal site, construction delays due to weather, and site licensing. This document provides an understanding of the steps, the sequence, the parties involved, and a representative duration of activities leading to remedial action and cleanup at the designated inactive uranium mill tailings sites. 10 refs., 5 figs., 1 tab.

Not Available

1985-07-01

265

Environmental assessment of remedial action at the Gunnison Uranium Mill Tailings Site, Gunnison, Colorado. [UMTRA Project  

SciTech Connect

This document assesses and compares the environmental impacts of various alternatives for remedial action at the Gunnison uranium of mill tailings site located 0.5 miles south of Gunnison, Colorado. The site covers 56 acres and contains 35 acres of tailings, 2 of the original mill buildings and a water tower. The Uranium Mill Tailings Radiation Control of Act of 1978 (UMTRCA), Public Law 95-604, authorizes the US Department of Energy to clean up the site to reduce the potential health impacts associated with the residual radioactive materials remaining at the site and at associated (vicinity) properties off the site. The US Environmental Protection Agency promulgated standards for the remedial actions (40 CFR 192). Remedial actions must be performed in accordance with these standards and with the occurrence of the Nuclear Regulatory Commission. Four alternatives have been addressed in this document. The first alternative is to consolidate the tailings and associated contaminated soils into a recontoured pile on the southern portion of the existing site. A radon barrier of silty clay would be constructed over the pile and various erosion control measures would be taken to assure the long-term integrity of the pile. Two other alternatives which involve moving the tailings to new locations are assessed in this document. These alternatives generally involve greater short-term impacts and are more costly but would result in the tailings being stabilized in a location farther from the city of Gunnison. The no action alternative is also assessed.

Bachrach, A.; Hoopes, J.; Morycz, D. (Jacobs Engineering Group, Inc., Pasadena, CA (USA)); Bone, M.; Cox, S.; Jones, D.; Lechel, D.; Meyer, C.; Nelson, M.; Peel, R.; Portillo, R.; Rogers, L.; Taber, B.; Zelle, P. (Weston (Roy F.), Inc., Washington, DC (USA)); Rice, G. (Sergent, Hauskins and Beckwith (USA))

1984-12-01

266

Mutation analysis of subjects with 46, XX sex reversal and 46, XY gonadal dysgenesis does not support the involvement of SOX3 in testis determination.  

PubMed

Despite the identification of an increasing number of genes involved in sex determination and differentiation, no cause can be attributed to most cases of 46, XY gonadal dysgenesis, approximately 20% of 46, XX males and the majority of subjects with 46, XX true hermaphroditism. Perhaps the most interesting candidate for involvement in sexual development is SOX3, which belongs to the same family of proteins (SOX) as SRY and SOX9, both of which are involved in testis differentiation. As SOX3 is the most likely evolutionary precursor to SRY, it has been proposed that it has retained a role in testis differentiation. Therefore, we screened the coding region and the 5' and 3' flanking region of the SOX3 gene for mutations by means of single-stranded conformation polymorphism and heteroduplex analysis in eight subjects with 46, XX sex reversal (SRY negative) and 25 subjects with 46, XY gonadal dysgenesis. Although no mutations were identified, a nucleotide polymorphism (1056C/T) and a unique synonymous nucleotide change (1182A/C) were detected in a subject with 46, XY gonadal dysgenesis. The single nucleotide polymorphism had a heterozygosity rate of 5.1% (in a control population) and may prove useful for future X-inactivation studies. The absence of SOX3 mutations in these patients suggests that SOX3 is not a cause of abnormal male sexual development and might not be involved in testis differentiation. PMID:11153920

Lim, H N; Berkovitz, G D; Hughes, I A; Hawkins, J R

2000-11-14

267

Strengthening of solidified dilute tailings slurry  

SciTech Connect

Tailings produced during mineral processing contain up to 75% or more water and are pumped into settling ponds for disposal. They often become a pollution source due to acid generation. While tailings have been used in underground backfill, the use is very limited at present. This paper presents research results on direct solidification and strengthening of the dilute tailings slurry without dewatering. Two types of tailings were tested at water/binder ratios of up to 4.5 using a special high-water binder. Adequate strength was achieved by solidifying the tailings as is. To further improve the strength, sands and fly ash were used as reinforcement materials or partial replacement of the binder. For oil sands tailings, the 3-day strength was increased by up to 114% with 10--15% additives. For hard rock tailings, up to 30% strength gain was achieved with 15% fly ash addition, and the strength was increased by up to 36% at 10% binder replacement and no strength reduction was observed at 20--25% replacement. These results indicate that higher strength can be achieved with the proper amount of additives and that the backfill process can be simplified and the operation cost reduced.

Zou, D.H.; Li, L.P. [Dalhousie Univ., Halifax, NS (Canada). Dept. Mining and Metallurgical Engineering

1999-01-01

268

75 FR 62445 - Otter Tail Valley Railroad Company, Inc.-Abandonment Exemption-in Otter Tail County, MN  

Federal Register 2010, 2011, 2012, 2013

...TRANSPORTATION Surface Transportation Board [Docket No. AB 330 (Sub-No. 4X)] Otter Tail Valley Railroad Company, Inc.-Abandonment Exemption-- in Otter Tail County, MN Otter Tail Valley Railroad Company, Inc. (OTVR) filed a verified notice...

2010-10-08

269

The tidal tails of globular cluster Palomar 5 based on the neural networks method  

NASA Astrophysics Data System (ADS)

The sixth Data Release (DR6) of the Sloan Digital Sky Survey (SDSS) provides more photometric regions, new features and more accurate data around globular cluster Palomar 5. A new method, Back Propagation Neural Network (BPNN), is used to estimate the cluster membership probability in order to detect its tidal tails. Cluster and field stars, used for training the networks, are extracted over a 40 × 20 deg2 field by color-magnitude diagrams (CMDs). The best BPNNs with two hidden layers and a Levenberg-Marquardt (LM) training algorithm are determined by the chosen cluster and field samples. The membership probabilities of stars in the whole field are obtained with the BPNNs, and contour maps of the probability distribution show that a tail extends 5.42° to the north of the cluster and another tail extends 3.77° to the south. The tails are similar to those detected by Odenkirchen et al., but no more debris from the cluster is found to the northeast in the sky. The radial density profiles are investigated both along the tails and near the cluster center. Quite a few substructures are discovered in the tails. The number density profile of the cluster is fitted with the King model and the tidal radius is determined as 14.28'. However, the King model cannot fit the observed profile at the outer regions (R > 8') because of the tidal tails generated by the tidal force. Luminosity functions of the cluster and the tidal tails are calculated, which confirm that the tails originate from Palomar 5.

Zou, Hu; Wu, Zhen-Yu; Ma, Jun; Zhou, Xu

2009-10-01

270

Myosin isoform fiber type and fiber size in the tail of the Virginia opossum (Didelphis virginiana).  

PubMed

Muscle fiber type is a well studied property in limb muscles, however, much less is understood about myosin heavy chain (MHC) isoform expression in caudal muscles of mammalian tails. Didelphid marsupials are an interesting lineage in this context as all species have prehensile tails, but show a range of tail-function depending on either their arboreal or terrestrial locomotor habits. Differences in prehensility suggest that MHC isoform fiber types may also be different, in that terrestrial opossums may have a large distribution of oxidative fibers for object carrying tasks instead of faster, glycolytic fiber types expected in mammals with long tails. To test this hypothesis, MHC isoform fiber type and their regional distribution (proximal/transitional/distal) were determined in the tail of the Virginia opossum (Didelphis virginiana). Fiber types were determined by a combination of myosin-ATPase histochemistry, immunohistochemistry, and SDS-PAGE. Results indicate a predominance of the fast MHC-2A and -2X isoforms in each region of the tail. The presence of two fast isoforms, in addition to the slow MHC-1 isoform, was confirmed by SDS-PAGE analysis. The overall MHC isoform fiber type distribution for the tail was: 25% MHC-1, 71% MHC-2A/X hybrid, and 4% MHC-1/2A hybrid. Oxidative MHC-2A/X isoform fibers were found to be relatively large in cross-section compared to slow, oxidative MHC-1 and MHC-1/2A hybrid fibers. A large percentage of fast MHC-2A/X hybrids fibers may be suggestive of an evolutionary transition in MHC isoform distribution (fast-to-slow fiber type) in the tail musculature of an opossum with primarily a terrestrial locomotor habit and adaptive tail-function. PMID:23152195

Hazimihalis, P J; Gorvet, M A; Butcher, M T

2012-11-14

271

Mercury's Dynamic Magnetic Tail (Invited)  

NASA Astrophysics Data System (ADS)

The Mariner 10 and MESSENGER flybys of Mercury have revealed a magnetosphere that is likely the most responsive to upstream interplanetary conditions of any in the solar system. The sources of the great dynamic variability observed during these brief flybys certainly include Mercury’s proximity to the Sun and the inverse proportionality between reconnection rate and solar wind Alfven Mach number. However, this planet’s lack of an ionosphere and its small physical dimensions also contribute. In particular, Mercury’s very brief Dungey cycle, ~ 2 min, which governs the time scale for internal plasma circulation, allows for very rapid transitions to new equilibrium states. Current observations and understanding of the structure and dynamics of Mercury’s magnetotail are summarized and discussed. Special emphasis will be placed upon such questions as: 1) How much access does the solar wind have to this small magnetosphere as a function of upstream conditions? 2) What roles do heavy planetary ions play? 3) Do Earth-like substorms take place at Mercury? 4) How does Mercury’s tail respond to extreme solar wind events such coronal mass ejections? Prospects for progress due to advances in the global magnetohydrodynamic and hybrid simulation modeling and the measurements to be taken by MESSENGER after it enters Mercury orbit on March 18, 2011 will be discussed.

Slavin, J. A.

2010-12-01

272

Helicopter main rotor\\/tail rotor noise radiation characteristics from scaled model rotor experiments in the DNW  

Microsoft Academic Search

A wind tunnel study was performed to investigate the noise characteristics and directivity pattern of a 40 percent scaled helicopter rotor system (BO 105 main\\/tail rotor model). The major objectives of the study were to establish the importance of the tail rotor with respect to the overall noise radiation and to determine the noise reduction potential of aerodynamically improved blade

K.-J. Schultz; W. R. Splettstoesser

1992-01-01

273

Enhancement of arsenic mobility by indigenous bacteria from mine tailings as response to organic supply  

Microsoft Academic Search

Arsenic leaching by indigenous bacteria in abandoned Au–Ag mine tailings which contained approximately 3200 mg\\/kg of As was investigated after supply of various organic substrates. Sequential extraction analysis designed to determine the mode of As occurrence in the tailings revealed that most As (90%) was closely associated with the Fe fraction. When glucose was supplied as a C source, indigenous bacteria

Jong-Un Lee; Sang-Woo Lee; Hyo-Taek Chon; Kyoung-Woong Kim; Jin-Soo Lee

2009-01-01

274

WINTER FAWN SURVIVAL IN BLACK-TAILED DEER POPULATIONS AFFECTED BY HAIR LOSS SYNDROME  

Microsoft Academic Search

Overwinter fawn mortality associated with hair loss syndrome (HLS) is anecdotally thought to be important in declines of Columbian black-tailed deer (Odocoileus hemionus col- umbianus) populations in Washington and Oregon (USA). We determined prevalence of HLS in black-tailed deer, September and April fawn:doe ratios, and minimum overwinter survival rates of fawns for selected game management units (GMUs) in western Washington

Louis C. Bender; P. Briggs Hall

275

Spatial analysis of Mycobacterium bovis infection in white-tailed deer ( Odocoileus virginianus) in Michigan, USA  

Microsoft Academic Search

The wild white-tailed deer (Odocoileus virginianus) population in Michigan, USA, has endemic Mycobacterium bovis. We determined whether there were spatial clusters of retrospective TB cases in white-tailed deer in northeastern Michigan and identified specific factors associated with the spatial clusters.Data from hunter-harvested deer (age, gender, TB status, and geographic section) were collected by the Michigan Department of Natural Resources (MDNR)

RoseAnn Miller; John B. Kaneene; Stephen M. Schmitt; David P. Lusch; Scott D. Fitzgerald

2007-01-01

276

Effects of dissolution kinetics on bioaccessible arsenic from tailings and soils  

Microsoft Academic Search

Dissolution kinetics of arsenic from soils and tailings were studied under simulated gastrointestinal conditions to determine the effects of residence time, pH and soil composition on the bioaccessibility of arsenic. The samples were sieved to four particle size fractions from bulk to <45?m, and included arsenic minerals, soils and tailings with total arsenic concentrations ranging from 19 to 42000mgkg?1. The

Louise Meunier; Iris Koch; Kenneth J. Reimer

2011-01-01

277

Three-dimensional structure of the bacteriophage P22 tail machine  

Microsoft Academic Search

The tail of the bacteriophage P22 is composed of multiple protein components and integrates various biological functions that are crucial to the assembly and infection of the phage. The three-dimensional structure of the P22 tail machine determined by electron cryo-microscopy and image reconstruction reveals how the five types of poly- peptides present as 51 subunits are organized into this molecular

Liang Tang; William R Marion; Gino Cingolani; Peter E Prevelige Jr; John E Johnson

2005-01-01

278

Social organization of cooperatively breeding long-tailed tits: kinship and spatial dynamics  

Microsoft Academic Search

Summary 1. Long-tailed tits Aegithalos caudatus L. are cooperative breeders in which breeders that have failed in their own breeding attempt become helpers at the nest of relatives. We investigated the effects of kinship on the spatial dynamics of non-breeding flocks of long-tailed tits in order to determine the information available on the kinship of other members of the population

B. J. HATCHWELL; C. ANDERSON; D. J. ROSS; M. K. FOWLIE; P. G. BLACKWELL

2001-01-01

279

Head-tail instability and Landau damping in bunches with space charge  

Microsoft Academic Search

Head-tail modes in bunches with space charge are studied using particle tracking simulations. The eigenfrequencies and eigenfunctions of transverse coherent oscillations in a Gaussian bunch are determined and compared with theories. A model for an airbag distribution in a barrier potential gives good predictions for the head-tail spectrum and for eigenfunctions in bunches with space charge. Using numerical simulations, space-charge

V. Kornilov; O. Boine-Frankenheim

2010-01-01

280

Engineering assessment of inactive uranium mill tailings: New and Old Rifle sites, Rifle, Colorado  

SciTech Connect

The New and Old Rifle sites were reevaluated in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Rifle, Colorado. This evaluation has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluaton and costing of alternative remedial actions.

Not Available

1981-08-01

281

Enhancement of arsenic mobility by indigenous bacteria from mine tailings as response to organic supply.  

PubMed

Arsenic leaching by indigenous bacteria in abandoned Au-Ag mine tailings which contained approximately 3200 mg/kg of As was investigated after supply of various organic substrates. Sequential extraction analysis designed to determine the mode of As occurrence in the tailings revealed that most As (90%) was closely associated with the Fe fraction. When glucose was supplied as a C source, indigenous bacteria significantly enhanced the extent of As release from the tailings into solution under both aerobic and anaerobic conditions. Anaerobic indigenous bacteria leached more amount of As from the tailings than aerobes. Highly positive correlation between the extracted amounts of As and Fe implied that microbial dissolution of Fe(III)-oxides, whether it was ligand- and proton-promoted dissolution or reductive dissolution, might be dominantly responsible for the As release. Bacterial strains which were resistant to up to 100 mM As(V) was aerobically isolated from the tailings. One of the isolates appeared to reduce some aqueous As(V) to likely As(III) in a batch type experiment, which indicated that indigenous bacteria can mediate the electrochemical speciation and thus the mobility of As in the tailings. The results suggest that indigenous bacteria in As-contaminated tailings can increase As mobility from the solid media when microbially available organic substrates are supplied, and thus enhance the risk of As dispersion to nearby soil, sediment and groundwater. PMID:18789531

Lee, Jong-Un; Lee, Sang-Woo; Chon, Hyo-Taek; Kim, Kyoung-Woong; Lee, Jin-Soo

2008-09-11

282

Radon attenuation handbook for uranium mill tailings cover design  

SciTech Connect

This handbook has been prepared to facilitate the design of earthen covers to control radon emission from uranium mill tailings. Radon emissions from bare and covered uranium mill tailings can be estimated from equations based on diffusion theory. Basic equations are presented for calculating surface radon fluxes from covered tailings, or alternately, the cover thicknesses required to satisfy a given radon flux criterion. Also described is a computer code, RAECOM, for calculating cover thicknesses and surface fluxes. Methods are also described for measuring diffusion coefficients for radon, or for estimating them from empirical correlations. Since long-term soil moisture content is a critical parameter in determining the value of the diffusion coefficient, methods are given for estimating the long-term moisture contents of soils. The effects of cover defects or advection are also discussed and guidelines are given for determining if they are significant. For most practical cases, advection and cover defect effects on radon flux can be neglected. Several examples are given to demonstrate cover design calculations, and an extensive list of references is included. 63 references, 18 figures, 6 tables.

Rogers, V.C.; Nielson, K.K.; Kalkwarf, D.R.

1984-04-01

283

Versatility and Stereotypy of Free-Tailed Bat Songs  

PubMed Central

In mammals, complex songs are uncommon and few studies have examined song composition or the order of elements in songs, particularly with respect to regional and individual variation. In this study we examine how syllables and phrases are ordered and combined, ie “syntax”, of the song of Tadarida brasiliensis, the Brazilian free-tailed bat. Specifically, we test whether phrase and song composition differ among individuals and between two regions, we determine variability across renditions within individuals, and test whether phrases are randomly ordered and combined. We report three major findings. First, song phrases were highly stereotyped across two regions, so much so that some songs from the two colonies were almost indistinguishable. All males produced songs with the same four types of syllables and the same three types of phrases. Second, we found that although song construction was similar across regions, the number of syllables within phrases, and the number and order of phrases in songs varied greatly within and among individuals. Last, we determined that phrase order, although diverse, deviated from random models. We found broad scale phrase-order rules and certain higher order combinations that were highly preferred. We conclude that free-tailed bat songs are composed of highly stereotyped phrases hierarchically organized by a common set of syntactical rules. However, within global species-specific patterns, songs male free-tailed bats dynamically vary syllable number, phrase order, and phrase repetitions across song renditions.

Bohn, Kirsten M.; Schmidt-French, Barbara; Schwartz, Christine; Smotherman, Michael; Pollak, George D.

2009-01-01

284

Relationship between tail-current sheet activation and dayside magnetosphere  

NASA Astrophysics Data System (ADS)

We report on multi-point observations of an isolated BZ disturbance detected at a wide local time sector including dayside magnetosphere in association with a tail current activation using THEMIS, Cluster, and Double Star observations around 01 UT on August 17, 2007. The unique constellation of the spacecraft allows us to examine simultaneously the propagation of the disturbance locally as well as globally. THEMIS at the late morning sector, observed an enhanced BZ disturbance that propagated tailward (and radial inward). TC1 at the dawnside detected relevant disturbance in BZ. Cluster, located post midnight sector, observed BZ enhancement accompanied with signature of field-aligned currents, in association with an enhancement of the westward electrojet observed by MIRACLE at a close local time sector. By comparing the timing of the disturbance and determining the propagation properties we discuss the possible casual relationship between the dayside disturbance and the tail current sheet activation.

Nakamura, R.; Keika, K.; Baumjohann, W.; Runov, A.; Magnes, W.; Eichelberger, H.; Angelopoulos, V.; McFadden, J.; Carlson, C. W.; Larson, D.; Glassmeier, K. H.; Auster, U.; Fornacon, K. H.; Lucek, E. A.; Carr, C. M.; Amm, O.; Fazakerley, A. N.; Reme, H.; Dandouras, I.; Klecker, B.; Daly, P.

2007-12-01

285

How do birds' tails work? Delta-wing theory fails to predict tail shape during flight.  

PubMed Central

Birds appear to use their tails during flight, but until recently the aerodynamic role that tails fulfil was largely unknown. In recent years delta-wing theory, devised to predict the aerodynamics of high-performance aircraft, has been applied to the tails of birds and has been successful in providing a model for the aerodynamics of a bird's tail. This theory now provides the conventional explanation for how birds' tails work. A delta-wing theory (slender-wing theory) has been used, as part of a variable-geometry model to predict how tail and wing shape should vary during flight at different airspeeds. We tested these predictions using barn swallows flying in a wind tunnel. We show that the predictions are not quantitatively well supported. This suggests that a new theory or a modified version of delta-wing theory is needed to adequately explain the way in which morphology varies during flight.

Evans, Matthew R; Rosen, Mikael; Park, Kirsty J; Hedenstrom, Anders

2002-01-01

286

Active Tails Enhance Arboreal Acrobatics in Geckos.  

National Technical Information Service (NTIS)

Geckos are nature's elite climbers. Their remarkable climbing feats have been attributed to specialized feet with hairy toes that uncurl and peel in milliseconds. Here, we report that the secret to the gecko s arboreal acrobatics includes an active tail. ...

A. Jusufi D. I. Goldman R. J. Full S. Revzen

2008-01-01

287

Quantitative Trait Loci Involved in Sex Determination and Body Growth in the Gilthead Sea Bream (Sparus aurata L.) through Targeted Genome Scan  

PubMed Central

Among vertebrates, teleost fish exhibit a considerably wide range of sex determination patterns that may be influenced by extrinsic parameters. However even for model fish species like the zebrafish Danio rerio the precise mechanisms involved in primary sex determination have not been studied extensively. The zebrafish, a gonochoristic species, is lacking discernible sex chromosomes and the sex of juvenile fish is difficult to determine. Sequential protandrous hermaphrodite species provide distinct determination of the gender and allow studying the sex determination process by looking at the mechanism of sex reversal. This is the first attempt to understand the genetic basis of phenotypic variation for sex determination and body weight in a sequential protandrous hermaphrodite species, the gilthead sea bream (Sparus aurata). This work demonstrates a fast and efficient strategy for Quantitative Trait Loci (QTL) detection in the gilthead sea bream, a non-model but target hermaphrodite fish species. Therefore a comparative mapping approach was performed to query syntenies against two other Perciformes, the European sea bass (Dicentrarchus labrax), a gonochoristic species and the Asian sea bass (Lates calcarifer) a protandrous hermaphrodite. In this manner two significant QTLs, one QTL affecting both body weight and sex and one QTL affecting sex, were detected on the same linkage group. The co-segregation of the two QTLs provides a genomic base to the observed genetic correlation between these two traits in sea bream as well as in other teleosts. The identification of QTLs linked to sex reversal and growth, will contribute significantly to a better understanding of the complex nature of sex determination in S. aurata where most individuals reverse to the female sex at the age of two years through development and maturation of the ovarian portion of the gonad and regression of the testicular area. [Genomic sequences reported in this manuscript have been submitted to GenBank under accession numbers HQ021443–HQ021749.

Loukovitis, Dimitrios; Sarropoulou, Elena; Tsigenopoulos, Costas S.; Batargias, Costas; Magoulas, Antonios; Apostolidis, Apostolos P.; Chatziplis, Dimitrios; Kotoulas, Georgios

2011-01-01

288

PREDATION ON MEXICAN FREE-TAILED BATS BY PEREGRINE FALCONS AND RED-TAILED HAWKS  

Microsoft Academic Search

We observed Red-tailed Hawks (Buteojamaicensis) and Peregrine Falcons (Falcoperegrinus) hunt- ing Mexican free-tailed bats (7kdarida brasiliensis) during their evening emergence and dawn return at Frio Cave, Uvalde County, Texas in the summer of 1997. Predation by Red-tailed Hawks occurred primarily in the evening (89.5%), and predation by Peregrine Falcons was mostly at dawn (90.5%). In the evening, hawks appeared when

YEN-MIN Kto

2001-01-01

289

ACTIVE VERTICAL TAIL BUFFETING ALLEVIATION ON A TWIN-TAIL FIGHTER CONFIGURATION IN A WIND TUNNEL  

Microsoft Academic Search

A 1\\/6-scale F-18 wind-tunnel model was tested in the Transonic Dynamics Tunnel at the NASA Langley Research Center as part of the Actively Controlled Response Of Buffet-Affected Tails (ACROBAT) program to assess the use of active controls in reducing vertical tail buffeting. The starboard vertical tail was equipped with an active rudder and other aerodynamic devices, and the port vertical

Robert W. Moses

290

The sodium tail of the Moon  

Microsoft Academic Search

During the few days centered about new Moon, the lunar surface is optically hidden from Earth-based observers. However, the Moon still offers an observable: an extended sodium tail. The lunar sodium tail is the escaping “hot” component of a coma-like exosphere of sodium generated by photon-stimulated desorption, solar wind sputtering and meteoroid impact. Neutral sodium atoms escaping lunar gravity experience

M. Matta; S. Smith; J. Baumgardner; J. Wilson; C. Martinis; M. Mendillo

2009-01-01

291

Probing the long tail of the magnetosphere  

Microsoft Academic Search

The ISEE-3 spacecraft has discovered a recognizable tail of the earth's magnetosphere which extends a million km beyond the moon's orbit. In the plasma sheet of the distant tail, plasma was found to be moving tailward as fast as 1000 km\\/sec, which is much faster than the speeds of a few tens of km\\/sec detected near the earth. Attention is

R. A. Kerr

1984-01-01

292

The ‘human tail’ causing tethered cervical cord  

Microsoft Academic Search

Study design:Human tails continue to elicit curiosity till the present times. A unique case of human cervical dysraphism is described.Objectives:In addition to the cosmetic stigma, these cutaneous markers provide a lead to reach the underlying spinal dysraphic states.Setting:Plains of North India.Methods:A case of human tail at the neck region is presented, whose cutaneous deformity lead the clinicians to his underlying

S Mohindra

2007-01-01

293

Engineering assessment of inactive uranium mill tailings, Shiprock site, Shiprock, New Mexico  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevaluated the Shiprock site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Shiprock, New Mexico. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.5 million dry tons of tailings at the Shiprock site constitutes the most significant environental impact, although windblown tailings and external gamma radiation also are factors. The eight alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through VIII). Cost estimates for the eight options range from about $13,400,000 for stabilization in place to about $37,900,000 for disposal at a distance of about 16 miles. Three principal alternatives for the reprocessing of the Shiprock tailings were examined: (a) heap leaching; (b) treatment at an existing mill; and (c) reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $230/lb by heap leach and $250/lb by conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery is not economically attractive.

Not Available

1981-07-01

294

Electrodialytic remediation of copper mine tailings.  

PubMed

Mining activities in Chile have generated large amounts of solid waste, which have been deposited in mine tailing impoundments. These impoundments cause concern to the communities due to dam failures or natural leaching to groundwater and rivers. This work shows the laboratory results of nine electrodialytic remediation experiments on copper mine tailings. The results show that electric current could remove copper from watery tailing if the potential gradient was higher than 2 V/cm during 21 days. With addition of sulphuric acid, the process was enhanced because the pH decreased to around 4, and the copper by this reason was released in the solution. Furthermore, with acidic tailing the potential gradient was less than 2 V/cm. The maximum copper removal reached in the anode side was 53% with addition of sulphuric acid in 21 days experiment at 20 V using approximately 1.8 kg mine tailing on dry basis. In addition, experiments with acidic tailing show that the copper removal is proportional with time. PMID:15629576

Hansen, Henrik K; Rojo, Adrián; Ottosen, Lisbeth M

2005-01-31

295

Field investigation of evaporation from freshwater tailings  

SciTech Connect

Safe and economical storage of tailings is now a major consideration in the operation of many mining operations. Tailings in slurried form, particularly if they have a significant clay content, can take a very long time to consolidate under the action of self-weight consolidation alone. However, if the operation is located in an area of high potential evaporation, this can be used to accelerate the rate of tailings densification. This paper presents a study of the evaporation behavior of a clayey tailings slurry deposited into an evaporation pond in the southwest of Western Australia. Over a six-month period, the rate of evaporation from the tailings surface was monitored using the Bowen Ratio method and the microlysimeter method. This was compared with the evaporation from a Class A pan located nearby. The tailings underwent very significant cracking as drying proceeded, and it was found that these cracks had a significant influence on the overall rate of evaporation once the top surface of the deposit started to desaturate. A large strain consolidation model was used to model the behavior, and the algorithm used in this model to include the effects of evaporation is shown to provide a reasonable prediction of the observed evaporation behavior.

Fujiyasu, Yoshimasa; Fahey, M.; Newson, T.

2000-06-01

296

Identification of regions interacting with ovo{sup D} mutations: Potential new genes involved in germline sex determination or differentiation in Drosophila melanogaster  

SciTech Connect

Only a few Drosophila melanogaster germline sex determination genes are known, and there have been no systematic screens to identify new genes involved in this important biological process. The ovarian phenotypes produced by females mutant for dominant alleles of the ovo gene are modified in flies with altered doses of other loci involved in germline sex determination in Drosophila (Sex-lethal{sup +}, snas fille{sup +} and ovarian tumor{sup +}). This observation constitutes the basis for a screen to identify additional genes required for proper establishment of germline sexual identity. We tested 300 deletions, which together cover {approximately}58% of the euchromatic portion of the genome, for genetic interactions with ovo{sup D}. Hemizygosity for more than a dozen small regions show interactions that either partially suppress or enhance the ovarian phenotypes of females mutant for one or more of the three dominant ovo mutations. These regions probably contain genes whose products act in developmental heirarchies that include ovo{sup +} protein. 40 refs, 7 figs., 5 tabs.

Pauli, D.; Oliver, B.; Mahowald, A.P. [Case Western Reserve Univ., Cleveland, OH (United States)

1995-02-01

297

Development of novel tail-modified anandamide analogs  

PubMed Central

To explore the hydrophobic groove subsite within the CB1 cannabinoid receptor we have designed and synthesized a group of tail-substituted anandamide analogs. Our design involves the introduction of aryl or heterocyclic ring as terminal substituents that are connected to the last cis-arachidonyl double bond through aliphatic chains of variable lengths. Our results indicate that there are strict stereochemical requirements for the interaction of such analogs with the CB1 receptor. The optimal pharmacophore includes the phenyl, p-substituted phenyl or 3-furyl substitutents attached to the cis-double bond through a four methylene chain.

Yao, Fenmei; Li, Chen; Vadivel, Subramanian K; Bowman, Anna L; Makriyannis, Alexandros

2013-01-01

298

Enhancement of Mineral Carbonation of Various Ultramafic Mine Tailings  

NASA Astrophysics Data System (ADS)

Capture of atmospheric CO2 in minerals to form magnesium and/or calcium carbonates is a process for permanent sequestration of CO2. Mineral carbonation occurs naturally in some ultramafic mining waste forming cemented crusts at surface, whereas reaction within the waste piles vents CO2-depleted air at the top of the piles. The purpose of this research is to kinetically enhance the mineral carbonation of different ultramafic mine tailings by addition of neutral organic salts and pH adjustments in order to reach a compromise between solubility of magnesium ions and carbonate precipitation. Real time monitoring of CO2 uptake at atmospheric conditions was performed using the Laval eudiometers, which allows calculation of the rate of the mineral carbonation reaction. Tests were conducted by varying the concentration of CO2 in the gas phase, the tailing water content and the material porosity to determine the optimal carbonation conditions. Subsequently, carbonation tests with different pH and various concentrations of organic salts (or chelate) such as sodium EDTA, sodium oxalate and sodium citrate were evaluated. Preliminary results indicate that CO2 reacts with the total mass of the sample and not only with the layer in contact with the gas phase. The water content for optimal carbonation reaction ranged from 20% and 60% according to the type of tailing investigated. Interstitial water is necessary as solvent for dissolution of Mg ions, but saturated pores reduce diffusion of CO2. A linear relationship was obtained between the CO2 concentration in the gas mixture and the CO2 absorption rate of the mine tailings. Increase of tailings porosity by addition of inert aluminum oxide enhances the carbonation reaction probably by facilitating CO2 diffusion in increased pore space. CO2 uptake was increased by 60% over distilled water, using a saturated solution of sodium citrate (1.5 M) and NaHCO3, by 14 to 19% using a saturated solution of sodium EDTA (0.2 M) and NaHCO3 and by 3 to 4% for a saturated solution of sodium oxalate (0.2 M) and NaHCO3. These data show that it is possible to significantly enhance the natural mineral carbonation reaction of various ultramafic mine tailings by adequate porosity, water content, increased CO2 concentration in air, and by adding chelating agents playing a role in Mg solubility at the surface of the Mg-rich minerals.

Tremblay, J.; Duchesne, J.; Beaudoin, G.; Constantin, M.; Hébert, R.; Larachi, F.; Lemieux, J.; Molson, J. W.

2011-12-01

299

EXPOSURE OF WHITE TAILED DEER TO BOVINE DIARRHEA VIRUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The importance of white tail deer as a reservoir of bovine viral diarrhea virus (BVDV) has been a point of controversy. The objective of this project was to observe the infectivity of BVDV white tail deer isolates in white tailed deer. Eight white tailed deer fawn 2-4 weeks in age were divided int...

300

Detection and tracking of low contrast human sperm tail  

Microsoft Academic Search

Tracking sperm tail movement provides important information for clinical sperm research. It is also a crucial step for sperm immobilization in Intracytoplasmic Sperm Injection (ICSI). However, the low visibility of the sperm tail under optical microscopy, coupled with the sperm fast motility, render sperm tail identification and tracking challenging tasks to execute. This paper presents two approaches for sperm tail

Clement Leung; Zhe Lu; Navid Esfandiari; Robert F. Casper; Yu Sun

2010-01-01

301

Engineering assessment of inactive uranium mill tailings, Tuba City site, Tuba City, Arizona  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevaluated the Tuba City site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Tuba City, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 0.8 million tons of tailings at the Tuba City site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors.

Not Available

1981-09-01

302

Calculation of the number of cancer deaths prevented by the Uranium Mill Tailings Remedial Action Project.  

PubMed

The Uranium Mill Tailings Remedial Action Project has completed remedial action at 22 uranium mill tailings sites and about 5,000 properties ("vicinity properties") where tailings were used in construction, at a total cost of $1.45 billion. This paper uses existing data from Environmental Impact Statements and Environmental Assessments, and vicinity property calculations, to determine the total number of cancer deaths averted by the Uranium Mill Tailings Remedial Action Project. The cost-effectiveness of remediating each site, the vicinity properties, and the entire project is calculated. The cost per cancer death averted was four orders of magnitude higher at the least cost-effective site than at the most cost-effective site. PMID:10201569

Miller, M L; Cornish, R E; Pomatto, C B

1999-05-01

303

Calculation of the number of cancer deaths prevented by the Uranium Mill Tailings Remedial Action Project  

SciTech Connect

The Uranium Mill Tailings Remedial Action Project has completed remedial action at 22 uranium mill tailings sites and about 5,000 properties (vicinity properties) where tailings were used in construction, at a total cost of $1.45 billion. This paper uses existing data from Environmental Impact Statements and Environmental Assessments, and vicinity property calculations, to determine the total number of cancer deaths averted by the Uranium Mill Tailings Remedial Action Project. The cost-effectiveness of remediating each site, the vicinity properties, and the entire project is calculated. The cost per cancer death averted was four orders of magnitude higher at the least cost-effective site than at the most cost-effective site.

Miller, M.L.; Pomatto, C.B. (Roy F. Weston, Inc., Albuquerque, NM (United States)); Cornish, R.E. (Dept. of Energy, Albuquerque, NM (United States). Albuquerque Operations Office)

1999-05-01

304

Raphe magnus/pallidus neurons regulate tail but not mesenteric arterial blood flow in rats.  

PubMed

In urethane-anesthetized rats with body temperature maintained at 39-40 degrees C, electrical stimulation of raphe magnus/pallidus/parapyramidal region within 0.5 mm of the ventral medullary surface reduced arterial blood flow to the tail cutaneous bed (measured with a chronically implanted Doppler ultrasonic flowmeter) from 28+/-5 to 6+/-1 cm/s (P<0.01), without changing mesenteric arterial blood flow, and with only small, variable changes in arterial pressure. Injection of bicuculline (50 pmol in 50 nl) at the same site reduced tail flow from 19+/-2 to 3+/-1 cm/s (P<0.01), again without significantly changing mesenteric flow, but with a moderate increase in arterial pressure. When the rat was cooled to reduce basal tail blood flow, injection of muscimol (1 nmol in 100 nl) or GABA (100 nmol in 100 nl) into the raphe site restored tail blood flow to 93+/-4% of the pre-cooling level. These recordings are the first reported direct measurements of rat tail blood flow changes elicited by alteration of neuronal function in the brainstem. The rostral medullary raphe controls the tail cutaneous vascular bed in a relatively selective manner. Our findings add to evidence that raphe magnus/pallidus/parapyramidal neurons are involved in regulating cutaneous blood flow in response to changes in body temperature in the rat. PMID:11530230

Blessing, W W; Nalivaiko, E

2001-01-01

305

Double chromodomains cooperate to recognize the methylated histone H3 tail  

SciTech Connect

Chromodomains are modules implicated in the recognition of lysine-methylated histone tails and nucleic acids. CHD (for chromo-ATPase/helicase-DNA-binding) proteins regulate ATP-dependent nucleosome assembly and mobilization through their conserved double chromodomains and SWI2/SNF2 helicase/ATPase domain. The Drosophila CHD1 localizes to the interbands and puffs of the polytene chromosomes, which are classic sites of transcriptional activity. Other CHD isoforms (CHD3/4 or Mi-2) are important for nucleosome remodelling in histone deacetylase complexes. Deletion of chromodomains impairs nucleosome binding and remodelling by CHD proteins. Here we describe the structure of the tandem arrangement of the human CHD1 chromodomains, and its interactions with histone tails. Unlike HP1 and Polycomb proteins that use single chromodomains to bind to their respective methylated histone H3 tails, the two chromodomains of CHD1 cooperate to interact with one methylated H3 tail. We show that the human CHD1 double chromodomains target the lysine 4-methylated histone H3 tail (H3K4me), a hallmark of active chromatin. Methylammonium recognition involves two aromatic residues, not the three-residue aromatic cage used by chromodomains of HP1 and Polycomb proteins. Furthermore, unique inserts within chromodomain 1 of CHD1 block the expected site of H3 tail binding seen in HP1 and Polycomb, instead directing H3 binding to a groove at the inter-chromodomain junction.

Flanagan, John F.; Mi, Li-Zhi; Chruszcz, Maksymilian; Cymborowski, Marcin; Clines, Katrina L.; Kim, Youngchang; Minor, Wladek; Rastinejad, Fraydoon; Khorasanizadeh, Sepideh (ANL/SBC); (UV)

2010-07-19

306

Escape of O+ Through the Distant Tail Plasma Sheet  

NASA Astrophysics Data System (ADS)

During the early orbit phase of the STEREO mission, in February, 2007, the STEREO-B spacecraft went down the deep magnetotail, and encountered the magnetosheath, plasma sheet and plasma sheet boundary layer from about 200 Re to 300 Re downtail, before finally exiting to the solar wind. This time period was during solar minimum, and there was no storm activity during this month. We have used the ion composition data from the PLASTIC instrument to determine how much ionospheric O+ is in the deep tail plasma sheet, and to calculate the loss rate through this path. Surprisingly, we find that during this solar and geomagnetically quiet time, O+ is a constant feature of the deep magnetotail. We find that the O+ density is about 15% of the density in the near-earth plasma sheet for similar conditions. The tailward flux of the O+ is similar to the flux of O+ beams that have been observed in the lobe/mantle region of the deep tail. The observations provide a consistent picture that some O+ is transported into the distant tail in the lobe/mantle region, and then enters the plasma sheet tailward of the distant neutral line. The total outflow of the O+ down the plasma sheet is a rate of 1.1x1024 ions/s, which is 10% of the total outflow rate of 1x 1025 ions/s, and of the same order as the estimated loss from dayside transport.

Kistler, L. M.; Galvin, A. B.; Popecki, M.; Simunac, K. D.; Farrugia, C. J.; Moebius, E.; Lee, M. A.; Blush, L. M.; Bochsler, P. A.; Wurz, P.; Klecker, B.; Wimmer-Schweingruber, R. F.; Opitz, A.; Sauvaud, J.; Russell, C. T.

2010-12-01

307

Tail buffet alleviation of high performance twin tail aircraft using offset piezoceramic stack actuators and acceleration feedback control  

Microsoft Academic Search

In High Performance Twin-Tail Aircraft (HPTTA), tail buffet occurs during high angles of attack maneuvers. At high angles of attack, flow separates and vortices are convected by the geometry of the wing-fuselage interface toward the vertical tails. This phenomenon, along with the aeroelastic coupling of the tail structural assembly, results in vibrations that can shorten the fatigue life of the

Maxime P. Bayon de Noyer

1999-01-01

308

Interference with the cytoplasmic tail of gp210 disrupts \\  

Microsoft Academic Search

e tested the hypothesis that gp210, an integral membrane protein of nuclear pore complexes (NPCs), mediates nuclear pore formation. Gp210 has a large lumenal domain and small COOH-terminal tail exposed to the cytoplasm. We studied the exposed tail. We added recombinant tail polypeptides to Xenopus nuclear assembly extracts, or inhibited endogenous gp210 tails using anti-tail antibodies. Both strategies had no

Sheona P. Drummond; Katherine L. Wilson

2002-01-01

309

Hydrology and geochemistry of the uranium mill tailings pile at Riverton, Wyoming. Part II. History matching. [Mathematical simulation of the observed fluid potentials within the tailings, and the observed distribution of various chemical species within and around the mill tailings  

SciTech Connect

In Part I of this series of two reports the observed fluid potential and geochemical characteristics in and around the inactive uranium mill tailings pile at Riverton, Wyoming were presented. The prupose of the present work is to attempt to simulate field observations using mathematical models. The results of the studies have not only helped identify the physicochemical mechanisms govering contaminant migration around the inactive mill tailings pile in Riverton, but also have indicated the feasibility of quantifying these mechanisms with the help of newly developed mathematical models. Much work needs to be done to validate and benchmark these models. The history-matching effort on hand involves the mathematical simulation of the observed fluid potentials within the tailings, and the observed distribution of various chemical species within and around the inactive uranium mill tailings. The simulation problem involves consideration of transient fluid flow and transient, reactive chemical transport in a variably saturated ground water system with time-dependent boundary conditions. 15 refs., 30 figs., 3 tabs.

Narasimhan, T.N.; White, A.F.; Tokunaga, T.

1985-02-01

310

Why do Birds have Tails? The Tail as a Drag Reducing Flap, and Trim Control  

Microsoft Academic Search

Birds have tails, bats do not. Does this fundamental difference in flight morphology reveal a difference in flight capability, and if so are birds or bats better fliers? I use Munk's stagger theorem, and Prandtl's relation for the induced drag of a biplane to show that for a given lift, and given wingspan, the induced drag of the wing-tail combination

Adrian L. R. Thomas

1996-01-01

311

The Effect of Competitive Outcome and Task-Involving, Ego-Involving, and Cooperative Structures on the Psychological Well-Being of Individuals Engaged in a CoOrdination Task: A Self-Determination Approach  

Microsoft Academic Search

Differing task and motivational characteristics of the competitive setting (viz., task-involving\\/ego-involving climates, cooperative\\/individual, and win\\/loss competitive outcome) were explored in relation to need satisfaction and subjective well-being (SWB). Participants, one-on-one or in pairs, were required to participate in a physical co-ordination task. Results revealed participants exposed to a task-involving condition and those who worked in cooperation to report higher levels

Martyn Standage; Joan L. Duda; Anne Marte Pensgaard

2005-01-01

312

Microtubule-associated protein 2 (MAP2) in Purkinje cell dendrites: Evidence that factors other than binding to microtubules are involved in determining its cytoplasmic distribution  

SciTech Connect

We have studied the distribution of microtubule-associated protein 2 (MAP2) in the Purkinje cell dendrites of rats whose cerebella were exposed to X-irradiation during the second postnatal week. The Purkinje cells of such animals have abnormally elongated apical primary processes that branch in the other molecular layer rather than close to the cell body as in normal tissue. The results show that in these distorted dendrites the MAP2 distribution is shifted distally relative to the normal pattern, in which MAP2 is distributed evenly throughout the dendritic tree. Tubulin and other microtubule-associated proteins, such as MAP1, are not affected and remain evenly distributed throughout the dendritic tree despite the anatomical distortion. We conclude that the distribution of MAP2 in Purkinje cells is not determined solely by its binding to tubulin. Other factors must be involved and these appear to be related to dendritic morphology and possibly to branching.

Matus, A.; Delhaye-Bouchaud, N.; Mariani, J. (Friedrich Miescher-Institut, Basel (Switzerland))

1990-07-15

313

Histone H3 Tails Containing Dimethylated Lysine and Adjacent Phosphorylated Serine Modifications Adopt a Specific Conformation during Mitosis and Meiosis? †  

PubMed Central

Condensation of chromatin, mediated in part by posttranslational modifications of histones, is essential for cell division during mitosis. Histone H3 tails are dimethylated on lysine (Kme2) and become phosphorylated on serine (Sp) residues during mitosis. We have explored the possibility that these double modifications are involved in the establishment of H3 tail conformations during the cell cycle. Here we describe a specific chromatin conformation occurring at Kme2 and adjacently phosphorylated S of H3 tails upon formation of a hydrogen bond. This conformation appears exclusively between early prophase and early anaphase of the mitosis, when chromatin condensation is highest. Moreover, we observed that the conformed H3Kme2Sp tail is present at the diplotene and metaphase stages in spermatocytes and oocytes. Our data together with results obtained by cryoelectron microscopy suggest that the conformation of Kme2Sp-modified H3 tails changes during mitosis and meiosis. This is supported by biostructural modeling of a modified histone H3 tail bound by an antibody, indicating that Kme2Sp-modified H3 tails can adopt at least two different conformations. Thus, the H3K9me2S10p and the H3K27me2S28p sites are involved in the acquisition of specific chromatin conformations during chromatin condensation for cell division.

Eberlin, Adrien; Grauffel, Cedric; Oulad-Abdelghani, Mustapha; Robert, Flavie; Torres-Padilla, Maria-Elena; Lambrot, Romain; Spehner, Daniele; Ponce-Perez, Lourdes; Wurtz, Jean-Marie; Stote, Roland H.; Kimmins, Sarah; Schultz, Patrick; Dejaegere, Annick; Tora, Laszlo

2008-01-01

314

A Black Hole Farey Tail  

Microsoft Academic Search

We derive an exact expression for the Fourier coefficients of elliptic genera of Calabi-Yau manifolds. When applied to k-fold symmetric products of K3 surfaces the expression is well-suited to studying the AdS\\/CFT correspondence on AdS3 x S3. The expression also elucidates an SL(2,Z) invariant phase diagram for the D1\\/D5 system involving deconfining transitions in the limit as k goes to

Robbert Dijkgraaf; Juan Maldacena; Gregory Moore; Erik Verlinde

2000-01-01

315

Targeting ADAM12 in human disease: head, body or tail?  

PubMed

ADAM12/meltrin alpha is a type I transmembrane multidomain protein involved in tumor progression and other severe diseases, including osteoarthritis, and as such could be considered as a potential drug target. In addition to protease activity, ADAM12 possesses cell binding and cell signaling properties. This functional trinity is reflected in the structure of ADAM12, which can be divided into head, body, and tail. The head of the protein (consisting of the pro and catalytic domains) mediates processing of growth factors and cytokines and has been implicated in epidermal growth factor (EGF) and insulin-like growth factor receptor signaling. The body of the protein (consisting of the disintegrin, cysteine-rich, and EGF-like domains) is involved in contacts with the extracellular matrix and other cells through interactions with integrins and syndecans. Finally, the tail of the protein (consisting of the cytoplasmic domain) is engaged in interactions with intracellular signaling molecules. In many studies, ADAM12 overexpression has been correlated with disease, and ADAM12 has been shown to promote tumor growth and progression in cancer. On the other hand, protective effects of ADAM12 in disease have also been reported. Future investigations should address the precise mechanisms of ADAM12 in disease and biology in order to counterbalance the benefits from targeting ADAM12 therapeutically with possible side effects. This review describes the biology of ADAM12, its association with disease, and evaluates the possible approaches to targeting ADAM12 in human disease. PMID:19601832

Jacobsen, J; Wewer, U M

2009-01-01

316

Structure and function of tuna tail tendons.  

PubMed

The caudal tendons in tunas and other scombrid fish link myotomal muscle directly to the caudal fin rays, and thus serve to transfer muscle power to the hydrofoil-like tail during swimming. These robust collagenous tendons have structural and mechanical similarity to tendons found in other vertebrates, notably the leg tendons of terrestrial mammals. Biochemical studies indicate that tuna tendon collagen is composed of the (alpha1)(2),alpha2 heterotrimer that is typical of vertebrate Type I collagen, while tuna skin collagen has the unusual alpha1,alpha2,alpha3 trimer previously described in the skin of some other teleost species. Tuna collagen, like that of other fish, has high solubility due to the presence of an acid-labile intermolecular cross-link. Unlike collagen in mammalian tendons, no differences related to cross-link maturation were detected among tendons in tuna ranging from 0.05 to 72 kg (approx. 0.25-6 years). Tendons excised post-mortem were subjected to load cycling to determine the modulus of elasticity and resilience (mean of 1.3 GPa and 90%, respectively). These material properties compare closely to those of leg tendons from adult mammals that can function as effective biological springs in terrestrial locomotion, but the breaking strength is substantially lower. Peak tendon forces recorded during steady swimming appear to impose strains of much less than 1% of tendon length, and no more than 1.5% during bursts. Thus, the caudal tendons in tunas do not appear to function as elastic storage elements, even at maximal swimming effort. PMID:12485695

Shadwick, Robert E; Rapoport, H Scott; Fenger, Joelle M

2002-12-01

317

Literature review of models for estimating soil erosion and deposition from wind stresses on uranium-mill-tailings covers  

SciTech Connect

Pacific Northwest Laboratory (PNL) is investigating the use of a rock armoring blanket (riprap) to mitigate wind and water erosion of an earthen radon-suppression cover applied to uranium-mill tailings. The mechanics of wind erosion, as well as of soil deposition, are discussed in this report. Several wind erosion models are reviewed to determine if they can be used to estimate the erosion of soil from a mill-tailings cover. One model, developed by W.S. Chepil, contains the most-important factors that describe variables that influence wind erosion. Particular features of other models are also discussed, as well as the application of Chepil's model to a particular tailings pile. For this particular tailings pile, the estimated erosion was almost one inch per year for an unprotected tailings soil surface. Wide variability in the deposition velocity and lack of adequate deposition models preclude reliable estimates of the rate at which airborne particles are deposited.

Bander, T.J.

1982-11-01

318

Survivability of ancient man-made earthen mounds: implications for uranium mill tailings impoundments  

Microsoft Academic Search

As part of a study for the Nuclear Regulatory Commission (NRC), the Pacific Northwest Laboratory (PNL) is investigating long-term stabilization techniques for uranium mill impoundments. Part of this investigation involves the design of a rock armoring blanket (riprap) to mitigate wind and water erosion of the underlying soil cover, which in turn prevents exposure of the tailings to the environment.

C. G. Lindsey; J. Mishima; S. E. King; W. H. Walters

1983-01-01

319

Optimizing habitat location for black-tailed prairie dogs in southwestern South Dakota  

Microsoft Academic Search

A spatial optimization model was formulated and used to maximize black-tailed prairie dog populations in the Badlands National Park and the Buffalo Gap National Grassland in South Dakota. The choice variables involved the strategic placement of limited additional protected habitat. Population dynamics were captured in formulations that reflected exponential population growth combined with the recalcitrant dispersal behavior of this social

John Hof; Michael Bevers; Daniel W. Uresk; Gregory L. Schenbeck

2002-01-01

320

The isolation of parvalbumin isoforms from the tail muscle of the american alligator ( Alligator mississipiensis)  

Microsoft Academic Search

Multiple parvalbumin isoforms have been detected in the tail (skeletal) muscle of the American alligator (Alligator mississipiensis). One of these isoforms (APV-1) has been highly purified and partially characterized. Protein purification involved mainly gel filtration and anion exchange chromatography, and characterization included gel electrophoresis, amino acid composition analysis, metal ion analysis, MALDI-TOF and ESI mass spectrometry, ultraviolet and fluorescence spectroscopy,

Ejel L Laney; Jeffrey Shabanowitz; Gina King; Donald F Hunt; Donald J Nelson

1997-01-01

321

Modelling of the TH-dependent regulation of tadpole tail resorption  

Microsoft Academic Search

Tail resorption observed at the time of amphibian metamorphosis is controlled by thyroid hormone. The inherent regulation network is complex and involves an important number of different factors. Consequently, the global understanding of this biological process needs elaborated experiments. However, these experiments can prove to be difficult to realize because of the need to manipulate in space and in time

S. Troncale; R. Thuret; A.-C. Fierro; C. Ben; N. Pollet; J.-P. Comet; G. Bernot

2007-01-01

322

Long Tail in electronic markets: Research on competition between niche products and featured products  

Microsoft Academic Search

The emergence of Long Tail in electronic markets illuminates that niche and obscure products which previously sold very little can make up a significant share of total sales. We build a circle city model with horizontal product differentiation to describe the electronic market involving niche products and a featured product. With the model, we analyze the competition between niche products

Yuhui Yang; Yan Zhu

2010-01-01

323

Characterization of syncrude sludge pond tailings  

SciTech Connect

The hot water process used by Suncor and Syncrude to extract bitumen from the Athabasca Oil Sands produces large volumes of tailings slurry. The fine grained sludge component of this waste is the most troublesome because of its stability and poor compaction potential. The sludge apparently owes its stability substantially to a complex interaction between organic coated amorphous particles, clays and bitumens. In this study the authors have investigated the nature of both the minerals and the associated organic matter present in a thickened, aqueous tailings sludge sample, from the syncrude Canada Limited plant. The findings of this study could be helpful in providing some insight into the nature of tailings pond sludge, a problem which poses the most imminent environmental constraint to future use of the hot water process.

Majid, A.; Boyko, V.J.; Sparks, B.D.; Ripmeester, J.A. (National Research Council of Canada, Ottawa, Ontario (Canada)); Kodama, H. (Chemistry and Biology Research Institute, Ottawa, Ontario (Canada))

1990-01-01

324

Design of tailing dam using red mud  

NASA Astrophysics Data System (ADS)

Red mud, waste industrial product from aluminum industries produced approximately 75 million tonnes every year with less than half of this is used. Storage of this unutilized red mud takes vast tracts of usable land and pollutes, land, air and water. Construction of high embankments, under passes, flyovers, tailing dams uses vast tract of natural resources (top soil) is also matter of concern as its takes thousands of years to form the natural soil. This paper discusses use of red mud for construction of tailing dam based on laboratory findings and finite element analysis. The geotechnical properties such as plasticity, compaction, permeability, shear strength characteristics and dispersion of red mud are presented. Stability and seepage analysis of tailing dams as per finite element analysis using the above geotechnical parameters is presented.

Rout, Subrat K.; Sahoo, Tapaswini; Das, Sarat K.

2013-06-01

325

Europa's FUV auroral tail on Jupiter  

NASA Astrophysics Data System (ADS)

Ultraviolet images of Jupiter's northern aurora obtained in 2005 confirm the existence of an electromagnetic interaction between Europa and the Jovian ionosphere. The auroral signature shows a two-component structure: a quasi-circular Europa spot, followed by a previously undetected faint tail emission trailing in the direction of corotation flow. The characteristic brightness for the auroral spot is ~14 +/- 1 kR above background, and approximately 7 +/- 1 kR for the tail. The spot's size is ~1100 km, magnetically mapping to an interaction region <=15 Europa diameters. The auroral tail extends over ~5000 km, which maps along a region of at least 70 Europa diameters. The ultraviolet power emitted by both components varies from a fraction to several GW. The present study suggests auroral interaction at Europa similar to that at Io, but scaled-down by an order of magnitude, including a sub-corotating plasma plume in the geometrical wake of Europa.

Grodent, D.; Gérard, J.-C.; Gustin, J.; Mauk, B. H.; Connerney, J. E. P.; Clarke, J. T.

2006-03-01

326

A Study on Solidification of Abandoned Mine Tailings with Hydrated Lime  

NASA Astrophysics Data System (ADS)

Solidification is one of the stabilization processes for wastes and their components to reduce their toxicity and migration rates to surroundings. Hydrated limes were applied as cementing materials to solidify heavy metal contaminated tailings from the Geumjang mine and the solidified tailing specimens were tested for their appropriateness in accordance with the suggested test methods. In the preliminary tests for the solidified tailing specimens, all the specimens have higher uniaxial compressive strengths than 3.5kgf/cm2, the standard recommended for land reclamation solids by EPA(Environmental Protection Agency). Even in leaching tests for the solidified tailing specimens, concentrations of heavy metals such as As, Cd, Cu, Pb, and Zn were decreased significantly below the environmental warning standards in comparison with those of raw tailing samples. The optimum mixing ratio of tailings, hydrated lime, and water was determined through the preliminary tests. The solidified mixtures of mine tailings and hydrated lime through pozzolanic reaction were tested for their durability against repeated freezing and thawing processes. After repeated freezing and thawing, the uniaxial compressive strengths of all the solidified mixture specimens decreased in comparison with those before test but still higher than 3.5kgf/cm2, and concentrations of heavy metals such as As, Cd, Cu, Pb, and Zn were below the standards. Effluents in the repetitive artificial tests show pH's of 7.4 to 9.1 and concentrations of heavy metals such as As, Cd, Cu, Pb, and Zn of below 0.05ppm. Conclusively this study shows potential applicability of hydrated limes to in-situ stabilization of abandoned mine tailings.

Min, K.; Lee, H.

2008-12-01

327

Wake Filling by Active Tail Articulation  

NASA Astrophysics Data System (ADS)

In a viscous fluid, the no slip boundary condition results in a surface drag force on a moving streamlined body, such as a hydrofoil, which causes a downstream wake velocity defect. In this paper, experimental results are presented which show that articulation of a trailing edge tail flap on a hydrofoil is sufficient to diminish the mean wake velocity defect. A 3 inch chord length NACA 0020 hydrofoil with a 1 inch long flapping trailing edge section was mounted in the research water tunnel at NUWC, Newport. Tests were conducted at speeds of 1, 2, and 4 m/s and the tail was flapped sinusoidally with amplitudes of 5, 10, and 20 degrees at varying frequencies. Time averaged velocity data was taken 1 chord length downstream by laser doppler velocimetry, LDV. Measurements with zero tail deflection show a velocity defect behind the hydrofoil of magnitude u/U = 0.88 and coefficient of drag, Cd, of approximately 0.02. Active articulation measurements show two regimes of wake filling. At very low Strouhal numbers it was found that tail articulation increases drag and is not useful for wake filling. In this range Cd is a function of flap deflection amplitude, St, and Re. However, above a certain threshold value, approximately St = 0.01, tail articulation begins to lessen the mean drag until Cd goes to zero around St = 0.06. At even higher St, tail articulation begins to produce thrust, resulting in a negative value of Cd. In the useful wake filling region, St 0.01, Cd seems to collapse to be a function of St only.

Macumber, Daniel; Beal, David; Annaswamy, Anuradha; Henoch, Charles; Huyer, Stephen

2004-11-01

328

Roles of macrophages in programmed cell death and remodeling of tail and body muscle of Xenopus laevis during metamorphosis  

Microsoft Academic Search

Examination was made of the involvement of macrophage phagocytosis in programmed cell death of tail and body muscle of the\\u000a frog, Xenopus laevis, during metamorphosis by electron microscopy and immunohistochemical analysis. Electron microscopic observation revealed\\u000a that macrophages were often found to be present in body and tail muscles at the most active stage of metamorphosis and to\\u000a actively phagocytose apoptotic

A. Nishikawa; Eiko Murata; Masumi Akita; Katsuji Kaneko; Osamu Moriya; Mitsuko Tomita; Hideo Hayashi

1997-01-01

329

TAIL1: an isthmin-like gene, containing type 1 thrombospondin-repeat and AMOP domain, mapped to ARVD1 critical region.  

PubMed

Isthmins represent a novel family of vertebrate secreted proteins containing one copy of the thrombospondin type 1 repeat (TSR), which in mammals is shared by several proteins with diverse biological functions, including cell adhesion, angiogenesis, and patterning of developing nervous system. We have determined the genomic organization of human TAIL1 (thrombospondin and AMOP containing isthmin-like 1), a novel isthmin-like gene encoding a protein that contains a TSR and a C-terminal AMOP domain (adhesion-associated domain in MUC4 and other proteins), characteristic of extracellular proteins involved in adhesion processes. TAIL1 gene encompasses more than 24.4 kb. Analysis of the DNA sequence surrounding the putative transcriptional start region revealed a TATA-less promoter located in a CpG island. Several consensus binding sites for the transcription factors Sp1 and MZF-1 were identified in this promoter region. In humans, TAIL1 gene is located on chromosome 14q24.3 within ARVD1 (arrhythmogenic right ventricular dysplasia/cardiomyopathy, type 1) critical region; preliminary evidence suggests that it is expressed in several tissues, showing multiple alternative splicing. PMID:15194193

Rossi, Valeria; Beffagna, Giorgia; Rampazzo, Alessandra; Bauce, Barbara; Danieli, Gian Antonio

2004-06-23

330

Radial tail resolution in the SELEX RICH  

SciTech Connect

The authors use a 7 Million event data sample of 600 GeV/c single track pion events, where the pion track is reconstructed upstream and downstream of the SELEX RICH. They build the RICH ring radius histogram distribution and count the tail events that fall outside 5{sigma}, giving a fraction of 4 x 10{sup -5} events outside the Gaussian tails. This control of events establishes the ability of using the RICH as velocity spectrometer for high precision searches of the K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}} decay like it is planned in the CKM experiment.

Morelos, A.; Mata, J.; Cooper, P.S.; Engelfried, J.; Aguilera-Servin, J.L.; /San Luis Potosi U. /Fermilab

2005-01-01

331

Dynamics of Histone Tails within Chromatin  

NASA Astrophysics Data System (ADS)

Genetic information in humans is encoded within DNA molecules that is wrapped around histone octamer proteins and compacted into a highly conserved structural polymer, chromatin. The physical and material properties of chromatin appear to influence gene expression by altering the accessibility of proteins to the DNA. The tails of the histones are flexible domains that are thought to play a role in regulating DNA accessibility and compaction; however the molecular mechanisms for these phenomena are not understood. I will present CW-EPR studies on site directed spin labeled nucleosomes that probe the structure and dynamics of these histone tails within nucleosomes.

Bernier, Morgan; North, Justin; Page, Michael; Jaroniec, Christopher; Hammel, Christopher; Poirier, Michael

2012-02-01

332

Mixing of propagules from discrete sources at long distance: comparing a dispersal tail to an exponential  

PubMed Central

Background Rare long distance dispersal events impact the demography and the genetic structure of populations. When dispersal is modelled via a dispersal kernel, one possible characterisation of long-distance dispersal is given by the shape of the tail of the kernel, i.e. its type of decay. This characteristic is known to directly act on the speed and pattern of colonization, and on the spatial structure of genetic diversity during colonization. In particular, colonization waves behave differently depending on whether the kernel decreases faster or slower than an exponential (i.e. is thin-tailed vs. fat-tailed). To interpret and extend published results on the impact of long-distance dispersal on the genetic structure of populations, we examine a classification of dispersal kernels based on the shape of their tails and formally demonstrate qualitative differences among them that can influence the predicted diversity of a propagule pool sampled far from two distinct sources. Results We show that a fat-tailed kernel leads asymptotically to a diverse propagule pool containing a balanced mixing of the propagules from the two sources, whereas a thin-tailed kernel results in all propagules originating from the closest source. We further show that these results hold for biologically relevant distances under certain circumstances, and in particular if the number of propagules is large enough, as would be the case for pollen or seeds. Conclusion To understand the impact of long-distance dispersal on the structure and dynamics of a metapopulation, it might be less important to precisely estimate an average dispersal distance than to determine if the tail of the dispersal kernel is fatter or thinner than that of an exponential function. Depending solely on this characteristic, a metapopulation will behave similarly to an island model with a diverse immigrant pool or to a stepping-stone model with migrants from closest populations. Our results further help to understand why thin-tailed dispersal kernels lead to a colonization wave of constant speed, whereas fat-tailed dispersal kernels lead to a wave of increasing speed. Our results also suggest that the diversity of the pollen cloud of a mother plant should increase with increasing isolation for fat-tailed kernels, whereas it should decrease for thin-tailed kernels.

Klein, Etienne K; Lavigne, Claire; Gouyon, Pierre-Henri

2006-01-01

333

Breeding biology and nest-site selection of red-tailed hawks in an altered desert grassland  

USGS Publications Warehouse

Red-tailed Hawks (Buteo jamaicensis) have expanded their range as trees have invaded formerly-open grasslands. Desert grasslands of southern Arizona have been invaded by mesquite trees (Prosopis velutina) since Anglo-American settlement and now support a large population of Red-tailed Hawks. We studied a population of Red-tailed Hawks in an altered desert grassland in southern Arizona. Our objectives were to determine what environmental characteristics influence Red-tailed Hawk habitat selection in mesquite-invaded desert grasslands and to evaluate the habitat quality of these grasslands for Red-tailed Hawks based on nesting density, nest success, and productivity. Red-tailed Hawks had 86% (95% C.I. = 73-99) nest success and 1.82 young per breeding pair (95% C.I. = 1.41-2.23). Nesting density was 0.15 (95% CI = 0.08-0.21) breeding pairs/km2 and the mean nearest-neighbor distance was 1.95 km (95% C.I. = 1.74-2.16). Red-tailed Hawks selected nest-sites with taller nest-trees and greater tree height and cover than were available at random. Mesquite trees in desert grasslands provide abundant potential nesting structures for Red-tailed Hawks. ?? 2006 The Raptor Research Foundation, Inc.

Hobbs, R. J.; DeStefano, S.; Halvorson, W. L.

2006-01-01

334

Engineering assessment of inactive uranium mill tailings, Rifle Site, Rifle, Colorado. Summary of the Phase II, Title I  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has performed an engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Rifle, Colorado. The Phase II - Title I services include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting radiation exposures of individuals and nearby populations, the investigation of site hydrology and meteorology and the evaluation and costing of alternative corrective actions. Radon gas release from the 3.1 million tons of tailings at the two Rifle sites, constitutes the most significant environmental impact. Windblown tailings, external gamma radiation and localized contamination of surface waters are other environmental effects. The 15 alternative remedial action options presented range from millsite decomtamination and off-site remedial action (Options I and IV), to adding various depths of stabilization cover material (Options II, V, VI, and VII), to removal of the tailings to long-term storage sites and decontamination of the present sites (Options III and VIII through XV). Cost estimates for the first 14 options range from $224,000 to $20,300,000. Option XV, estimated at $32,200,000, includes the cost for moving both Rifle tailings piles and the Grand Junction tailings pile to DeBeque for long-term storage and site decontamination after removal of the piles. Reprocessing of the tailings for uranium appears to be economically attractive at present.

Not Available

1977-10-01

335

Asymptotic solutions of decoupled continuous-time random walks with superheavy-tailed waiting time and heavy-tailed jump length distributions  

NASA Astrophysics Data System (ADS)

We study the long-time behavior of decoupled continuous-time random walks characterized by superheavy-tailed distributions of waiting times and symmetric heavy-tailed distributions of jump lengths. Our main quantity of interest is the limiting probability density of the position of the walker multiplied by a scaling function of time. We show that the probability density of the scaled walker position converges in the long-time limit to a nondegenerate one only if the scaling function behaves in a certain way. This function as well as the limiting probability density are determined in explicit form. Also, we express the limiting probability density which has heavy tails in terms of the Fox H function and find its behavior for small and large distances.

Denisov, S. I.; Yuste, S. B.; Bystrik, Yu. S.; Kantz, H.; Lindenberg, K.

2011-12-01

336

Liquid chromatography-electrospray mass spectrometry determination of ibogaine and noribogaine in human plasma and whole blood. Application to a poisoning involving Tabernanthe iboga root.  

PubMed

A liquid chromatography/electrospray ionization mass spectrometry (LC-ESI-MS) method was developed for the first time for the determination of ibogaine and noribogaine in human plasma and whole blood. The method involved solid phase extraction of the compounds and the internal standard (fluorescein) from the two matrices using OasisHLB columns. LC separation was performed on a Zorbax eclipse XD8 C8 column (5 microm) with a mobile phase of acetonitrile containing 0.02% (v/v) trimethylamine and 2mM ammonium formate buffer. MS data were acquired in single ion monitoring mode at m/z 311.2, 297.2 and 332.5 for ibogaine, noribogaine and fluorescein, respectively. The drug/internal standard peak area ratios were linked via a quadratic relationship to plasma (0.89-179 microg/l for ibogaine; 1-200 microg/l for noribogaine) and to whole blood concentrations (1.78-358 microg/kg for ibogaine; 2-400 microg/kg for noribogaine). Precision ranged from 4.5 to 13% and accuracy was 89-102%. Dilution of the samples had no influence on the performance of the method. Extraction recoveries were > or =94% in plasma and > or =57% in whole blood. The lower limits of quantitation were 0.89 microg/l for ibogaine and 1 microg/l for noribogaine in plasma, and 1.78 microg/kg for ibogaine and 2 microg/kg for noribogaine in whole blood. In frozen plasma samples, the two drugs were stable for at least 1 year. In blood, ibogaine and noribogaine were stable for 4h at 4 degrees C and 20 degrees C and 2 months at -20 degrees C. The method was successfully used for the analysis of a poisoning involving Tabernanthe iboga root. PMID:16798116

Kontrimavici?te, Violeta; Breton, Hélène; Mathieu, Olivier; Mathieu-Daudé, Jean-Claude; Bressolle, Françoise M M

2006-06-23

337

Tailings Pond Characterization And Designing Through Geophysical Surveys In Dipping Sedimentary Formations  

NASA Astrophysics Data System (ADS)

Mining activities results into generation of disintegrated waste materials attaining increased mobilization status and requires a safe disposal mechanism through back filling process or secluded storage on surface with prevention of its interaction with environment cycle. The surface disposal of waste materials will become more critical in case of mined minerals having toxic or radioactive elements. In such cases, the surface disposal site is to be characterized for its sub-surface nature to understand its role in environmental impact due to the loading of waste materials. Near surface geophysics plays a major role in mapping the geophysical characters of the sub-surface formations in and around the disposal site and even to certain extent helps in designing of the storage structure. Integrated geophysical methods involving resistivity tomography, ground magnetic and shallow seismic studies were carried out over proposed tailings pond area of 0.3 sq. kms underlined by dipping sedimentary rocks consisting of ferruginous shales and dolomitic to siliceous limestone with varying thicknesses. The investigated site being located in tectonically disturbed area, geophysical investigations were carried out with number of profiles to visualize the sub-surface nature with clarity. The integration of results of twenty profiles of resistivity tomography with 2 m (shallow) and 10 m (moderate depth) electrode spacing’s enabled in preparing probable sub-surface geological section along the strike direction of the formation under the tailings pond with some geo-tectonic structure inferred to be a fault. Similarly, two resistivity tomography profiles perpendicular to the strike direction of the formations brought out the existence of buried basic intrusive body on the northern boundary of the proposed tailings pond. Two resistivity tomography profiles in criss-cross direction over the suspected fault zone confirmed fault existence on the north-eastern part of tailings pond. Thirty two magnetic profiles inside the tailings pond and surrounding areas on the southern part of the tailings pond enabled in identifying two parallel east-west intrusive bodies forming the impermeable boundary for the tailings pond. The shallow seismic refraction and the geophysical studies in and around the proposed tailings pond brought out the suitability of the site, even when the toxic elements percolates through the subsurface formations in to the groundwater system, the existence of dykes on either side of the proposed ponding area won’t allow the water to move across them thus by restricting the contamination within the tailings pond area. Similarly, the delineation of a fault zone within the tailings pond area helped in shifting the proposed dam axis of the pond to avoid leakage through the fault zone causing concern to environment pollution.

Muralidharan, D.; Andrade, R.; Anand, K.; Sathish, R.; Goud, K.

2009-12-01

338

Chemistry and biology of solid wastes, dredge materials and mine tailings  

SciTech Connect

This book examines in 12 chapters the chemical and mineralogical trace element characteristics of dredged sediments and mine tailings, and the chemical and biological processes that determine the fate of trace elements from these two sources in the terrestrial and aquatic environment. This volume is the first of two, the second entitled Environmental Management of Dredged Material and Mine Tailings. The specific subject matter of this book is prefaced by three review chapters on the chemical and biological processes that determine trace element environmental fate. The remaining nine chapters can be classified into two types: case histories and assessment methodology.

Salomons, W.; Forstner, U. (eds.)

1988-01-01

339

Significance of Microbial Communities and Interactions in Safeguarding Reactive Mine Tailings by Ecological Engineering?†  

PubMed Central

Pyritic mine tailings (mineral waste generated by metal mining) pose significant risk to the environment as point sources of acidic, metal-rich effluents (acid mine drainage [AMD]). While the accelerated oxidative dissolution of pyrite and other sulfide minerals in tailings by acidophilic chemolithotrophic prokaryotes has been widely reported, other acidophiles (heterotrophic bacteria that catalyze the dissimilatory reduction of iron and sulfur) can reverse the reactions involved in AMD genesis, and these have been implicated in the “natural attenuation” of mine waters. We have investigated whether by manipulating microbial communities in tailings (inoculating with iron- and sulfur-reducing acidophilic bacteria and phototrophic acidophilic microalgae) it is possible to mitigate the impact of the acid-generating and metal-mobilizing chemolithotrophic prokaryotes that are indigenous to tailing deposits. Sixty tailings mesocosms were set up, using five different microbial inoculation variants, and analyzed at regular intervals for changes in physicochemical and microbiological parameters for up to 1 year. Differences between treatment protocols were most apparent between tailings that had been inoculated with acidophilic algae in addition to aerobic and anaerobic heterotrophic bacteria and those that had been inoculated with only pyrite-oxidizing chemolithotrophs; these differences included higher pH values, lower redox potentials, and smaller concentrations of soluble copper and zinc. The results suggest that empirical ecological engineering of tailing lagoons to promote the growth and activities of iron- and sulfate-reducing bacteria could minimize their risk of AMD production and that the heterotrophic populations could be sustained by facilitating the growth of microalgae to provide continuous inputs of organic carbon.

Nancucheo, Ivan; Johnson, D. Barrie

2011-01-01

340

Significance of microbial communities and interactions in safeguarding reactive mine tailings by ecological engineering.  

PubMed

Pyritic mine tailings (mineral waste generated by metal mining) pose significant risk to the environment as point sources of acidic, metal-rich effluents (acid mine drainage [AMD]). While the accelerated oxidative dissolution of pyrite and other sulfide minerals in tailings by acidophilic chemolithotrophic prokaryotes has been widely reported, other acidophiles (heterotrophic bacteria that catalyze the dissimilatory reduction of iron and sulfur) can reverse the reactions involved in AMD genesis, and these have been implicated in the "natural attenuation" of mine waters. We have investigated whether by manipulating microbial communities in tailings (inoculating with iron- and sulfur-reducing acidophilic bacteria and phototrophic acidophilic microalgae) it is possible to mitigate the impact of the acid-generating and metal-mobilizing chemolithotrophic prokaryotes that are indigenous to tailing deposits. Sixty tailings mesocosms were set up, using five different microbial inoculation variants, and analyzed at regular intervals for changes in physicochemical and microbiological parameters for up to 1 year. Differences between treatment protocols were most apparent between tailings that had been inoculated with acidophilic algae in addition to aerobic and anaerobic heterotrophic bacteria and those that had been inoculated with only pyrite-oxidizing chemolithotrophs; these differences included higher pH values, lower redox potentials, and smaller concentrations of soluble copper and zinc. The results suggest that empirical ecological engineering of tailing lagoons to promote the growth and activities of iron- and sulfate-reducing bacteria could minimize their risk of AMD production and that the heterotrophic populations could be sustained by facilitating the growth of microalgae to provide continuous inputs of organic carbon. PMID:21965397

Nancucheo, Ivan; Johnson, D Barrie

2011-09-30

341

Research Model Wing/Tail Fabrication.  

National Technical Information Service (NTIS)

The design and construction of a transonic wind-tunnel model has been completed. The 1/7.5-scale model can be equipped with an all-flying low-, mid-, or T-tail. A baseline, linear element wing and an alternate wing of identical planform, but with chordwis...

R. A. Cox

1982-01-01

342

Canadian Experience with Uranium Tailings Disposal.  

National Technical Information Service (NTIS)

During the first years of uranium production in Canada uranium tailings were discharged directly into valleys or lakes near the mill. Treatment with barium chloride to precipitate radium began in 1965 at the Nordic Mine at Elliot Lake, Ontario. In the mid...

K. B. Culver

1982-01-01

343

White-tailed spider bites - arachnophobic fallout?  

Microsoft Academic Search

Aim To investigate if public concern regarding the toxic effects of the bites from white-tailed spiders, Lampona cylindrata and L. murina, is reflected in the case histories of patients admitted to Christchurch Hospital with a diagnosis of spider bite. Methods The case histories of patients admitted to Christchurch Hospital with a diagnosis of 'contact with venomous spiders' were examined for

Jonathan Banks; Phil Sirvid; Cor Vink

344

Functional morphology of the aardvark tail.  

PubMed

The musculoskeletal system of the aardvark (Orycteropus afer) tail was morphologically examined in two adult specimens. The tail musculature comprised three muscular groups, viz. a dorsal sacrocaudal system that consisted of the irregularly oriented Musculus sacrocaudalis dorsalis medialis and M. sacrocaudalis dorsalis lateralis, a lateral inter-vertebral connecting system, and a ventral sacrocaudal system characterized by the thick M. sacrocaudalis ventralis lateralis and M. sacrocaudalis ventralis medialis. Both the dorsal and ventral systems possessed large tendon groups that strengthened the tail structure. Computed tomography (CT) examination showed the presence of large but homogeneous cartilaginous inter-vertebral discs, whereas V-shaped bones were situated at the ventral aspect of the caudal vertebrae at the level of the inter-vertebral discs. CT visualization of the tendons and V-shaped bones in various tail positions suggested that these structures contribute to the tunnel digging action by bearing the trunk weight and lending force when the aardvark are displacing the soil by means of the forelimbs. PMID:22713114

Endo, H; Mori, K; Koyabu, D; Kawada, S; Komiya, T; Itou, T; Koie, H; Kitagawa, M; Sakai, T

2012-06-19

345

Design of Tailings Dams and Impoundments  

Microsoft Academic Search

The state of practice for tailings dam and impoundment design is summarized. The design process, which embraces construction, operational and closure issues together with requisite technical aspects, has evolved over the past several decades though the engineering principles have remained the same. The design process has evolved to meet the demands of a regulatory environment that has become increasingly stringent

Michael P. Davies; Peter C. Lighthall; Steve Rice; Todd E. Martin

346

Mine Waste Technology Program Electrochemical Tailings Cover  

EPA Science Inventory

This report summarizes the results of Mine Waste Technology Program (MWTP) Activity III, Project 40, Electrochemical Tailings Cover, funded by the U.S. Environmental Protection Agency (EPA) and jointly administered by EPA and the U.S. Department of Energy (DOE). MSE Technology A...

347

Optimal Reinsurance Arrangements Under Tail Risk Measures  

Microsoft Academic Search

Abstract Regulatory authorities demand insurance companies control their risk exposure by imposing stringent risk management policies. This article investigates the optimal risk management strategy of an insurance company subject to regulatory constraints. We provide optimal reinsurance contracts under different tail risk measures and analyze the impact of regulators' requirements on risk sharing in the reinsurance market. Our results underpin adverse

Carole Bernard; Weidong Tian

2009-01-01

348

Dispersal in female white-tailed deer  

USGS Publications Warehouse

Seven of 35 yearling female white-tailed deer (Odocoileus virginianus) in a migratory herd in northeastern Minnesota dispersed 18-168 km from natal ranges during late May through June. Dispersal as a proximate event appears voluntary and independent of deer density.

Nelson, M. E.; Mech, L. D.

1992-01-01

349

Wake Filling by Active Tail Articulation  

Microsoft Academic Search

In a viscous fluid, the no slip boundary condition results in a surface drag force on a moving streamlined body, such as a hydrofoil, which causes a downstream wake velocity defect. In this paper, experimental results are presented which show that articulation of a trailing edge tail flap on a hydrofoil is sufficient to diminish the mean wake velocity defect.

Daniel Macumber; David Beal; Anuradha Annaswamy; Charles Henoch; Stephen Huyer

2004-01-01

350

Molasses Tail in Dense Hard Core Fluids  

NASA Astrophysics Data System (ADS)

The long slow decaying potential part of the shear-stress autocorrelation function has been called the ``molasses tail'' to differentiate it from the hydrodynamic origin of the long time tail in the velocity autocorrelation function and to emphasize its relation to the highly viscous glassy state [1]. Some twenty years ago, the molasses tail in dense liquids near the solid-fluid transition point was speculated to be due to transient crystal nuclei formation [2].This slow decaying process of the OACF and its decomposition (pair, triplet, and quadruplet) is a key factor in understanding the onset of the glass transition. With additional computer power, we are now investigating the origin of the molasses tail using a modern fast algorithm based on event-driven Molecular Dynamics (MD) simulation.We confirm the non-algebraic decay (stretched exponential) at intermediate times corresponding to the existence of various cluster sizes a solid cluster at high densities. The decay in dense systems thus consists of a three stage relaxation process, which are the kinetic regime, the molasses regime and the diffusional power regime[3]. [1] B. J. Alder, in Molecular Dynamics Simulation of Statistical-mechanical Systems, G. Ciccotti and W. G. Hoover, eds.(North-Holland, Amsterdam, 1986) 66. [2] A. J. C. Ladd, and B. J. Alder, J. Stat. Phys. 57, 473 (1989). [3] M. Isobe and B. J. Alder, Mol. Phys., 107, 609 (2009).

Isobe, Masaharu; Alder, Berni

2010-03-01

351

Long Tail Recommender Utilizing Information Diffusion Theory  

Microsoft Academic Search

Our approach aims to provide a mechanism for recommending long tail items to knowledge workers. The approach employs collaborative filtering using browsing features of identified key population of the diffusion of information. We conducted analytic experiment for a novel recommendation algorithm based on the browsing features of identified selected users and discovered that the first 10 users accessing a particular

Masayuki Ishikawa; Peter Géczy; Noriaki Izumi; Takahira Yamaguchi

2008-01-01

352

A Novel Asymmetric Distribution with Power Tails  

Microsoft Academic Search

In this article, we propose a four-parameter asymmetric doubly Pareto-uniform (DPU) distribution with support (??, ?) whose density and cumulative distribution functions are constructed by seamlessly concatenating the left and right Pareto tails with a uniform central part. Properties of the distribution are described and a maximum likelihood estimation (MLE) procedure for its parameters is obtained. Two illustrative examples of

Amita Singh; J. René van Dorp; Thomas A. Mazzuchi

2007-01-01

353

CREEP RUPTURE OF WALLABY TAIL TENDONS  

Microsoft Academic Search

The tail tendons from wallabies ( Macropus rufogriseus) suffer creep rupture at stresses of 10 MPa or above, whereas their yield stress in a dynamic test is about 144 MPa. At stresses between 20 and 80 MPa, the time-to- rupture decreases exponentially with stress, but at 10 MPa, the lifetime is well above this exponential. For comparison, the stress on

XIAO TONG WANG; ROBERT F. KER

354

Neuroectodermal Appendages: The Human Tail Explained  

Microsoft Academic Search

The human tail has been intermittently described in the literature since the early 1900s. These have typically been isolated cases presented primarily with intrigue and medical curiosity. Presented here is a series of 6 neuroectodermal appendages with a proposal for their etiological development. The material presented will support a theory of the superficial extension of a dermal sinus tract in

Sarah J. Gaskill; Arthur E. Marlin

1989-01-01

355

Structure and Development of Cometary Tail.  

National Technical Information Service (NTIS)

The physical conditions in comets which lead to the formulation of type I-tails are discussed. The report comprises the following five seperate papers: (1) The ionization in comets; (2) brightness and structure of the Na-emission in comets; (3) the heads ...

K. Wurm

1964-01-01

356

Uranium mill tailings and risk estimation  

SciTech Connect

Work done in estimating projected health effects for persons exposed to mill tailings at vicinity properties is described. The effect of the reassessment of exposures at Hiroshima and Nagasaki on the risk estimates for gamma radiation is discussed. A presentation of current results in the epidemiological study of Hanford workers is included. 2 references. (ACR)

Marks, S.

1984-04-01

357

Investigation of environmental impacts of tailings dams  

Microsoft Academic Search

Mining has been one of the key sectors for industrialisation of the world for centuries. As the mining activities enlarge, the amount of waste materials readily increases. Storage of waste materials or tailings disposal has become a serious matter for the mining industry due to its enlargement especially for the last 30 years. During the beneficiation of valuable metals and

Safak Ozkan; Bedri Ipekoglu

2002-01-01

358

Band tails and bandwidth in simple metals  

Microsoft Academic Search

Electron-electron interactions are included in a calculation of the density of states for the homogeneous electron gas. The shift of the chemical potential is investigated from band tails and quasiparticle renormalization. These effects largely cancel, and the shift of the chemical potential is small.

H. O. Frota; G. D. Mahan

1992-01-01

359

Tail Pressure Release Through Auroral Acceleration  

Microsoft Academic Search

Earthward convecting plasma has to circumvent the Earth on its way from the tail reconnection region to the dayside magnetosphere. This leads to radially sheared flows between the corotating plasmasphere and the low-latitude boundary layer. Consequently, embedded magnetic field lines also become sheared and set up field-aligned currents which must close in the highly conducting auroral ionosphere. As- sociated electric

E. M. Blixt; J. Vogt

2001-01-01

360

Flight costs of long, sexually selected tails in hummingbirds  

PubMed Central

The elongated tails adorning many male birds have traditionally been thought to degrade flight performance by increasing body drag. However, aerodynamic interactions between the body and tail can be substantial in some contexts, and a short tail may actually reduce rather than increase overall drag. To test how tail length affects flight performance, we manipulated the tails of Anna's hummingbirds (Calypte anna) by increasing their length with the greatly elongated tail streamers of the red-billed streamertail (Trochilus polytmus) and reducing their length by removing first the rectrices and then the entire tail (i.e. all rectrices and tail covert feathers). Flight performance was measured in a wind tunnel by measuring (i) the maximum forward speed at which the birds could fly and (ii) the metabolic cost of flight while flying at airspeeds from 0 to 14?m?s?1. We found a significant interaction effect between tail treatment and airspeed: an elongated tail increased the metabolic cost of flight by up to 11 per cent, and this effect was strongest at higher flight speeds. Maximum flight speed was concomitantly reduced by 3.4 per cent. Also, removing the entire tail decreased maximum flight speed by 2 per cent, suggesting beneficial aerodynamic effects for tails of normal length. The effects of elongation are thus subtle and airspeed-specific, suggesting that diversity in avian tail morphology is associated with only modest flight costs.

James Clark, Christopher; Dudley, Robert

2009-01-01

361

[Family Involvement.  

ERIC Educational Resources Information Center

|This theme issue provides four articles that address family involvement in the transition of youth with disabilities from school to work. The first article, "Family Involvement" by Marge Goldberg and Shauna McDonald, offers evidence of the importance of family involvement at this stage of the individual's life, reports on families' experiences,…

Alliance: The Newsletter of the National Transition Alliance, 1996

1996-01-01

362

DNA inversion regions Min of plasmid p15B and Cin of bacteriophage P1: evolution of bacteriophage tail fiber genes.  

PubMed Central

Plasmid p15B and the genome of bacteriophage P1 are closely related, but their site-specific DNA inversion systems, Min and Cin, respectively, do not have strict structural homology. Rather, the complex Min system represents a substitution of a Cin-like system into an ancestral p15B genome. The substituting sequences of both the min recombinase gene and the multiple invertible DNA segments of p15B are, respectively, homologous to the pin recombinase gene and to part of the invertible DNA of the Pin system on the defective viral element e14 of Escherichia coli K-12. To map the sites of this substitution, the DNA sequence of a segment adjacent to the invertible segment in the P1 genome was determined. This, together with already available sequence data, indicated that both P1 and p15B had suffered various sequence acquisitions or deletions and sequence amplifications giving rise to mosaics of partially related repeated elements. Data base searches revealed segments of homology in the DNA inversion regions of p15B, e14, and P1 and in tail fiber genes of phages Mu, T4, P2, and lambda. This result suggest that the evolution of phage tail fiber genes involves horizontal gene transfer and that the Min and Pin regions encode tail fiber genes. A functional test proved that the p15B Min region carries a tail fiber operon and suggests that the alternative expression of six different gene variants by Min inversion offers extensive host range variation. Images

Sandmeier, H; Iida, S; Arber, W

1992-01-01

363

NPS6, Encoding a Nonribosomal Peptide Synthetase Involved in Siderophore-Mediated Iron Metabolism, Is a Conserved Virulence Determinant of Plant Pathogenic Ascomycetes[W  

PubMed Central

NPS6, encoding a nonribosomal peptide synthetase, is a virulence determinant in the maize (Zea mays) pathogen Cochliobolus heterostrophus and is involved in tolerance to H2O2. Deletion of NPS6 orthologs in the rice (Oryza sativa) pathogen, Cochliobolus miyabeanus, the wheat (Triticum aestivum) pathogen, Fusarium graminearum, and the Arabidopsis thaliana pathogen, Alternaria brassicicola, resulted in reduced virulence and hypersensitivity to H2O2. Introduction of the NPS6 ortholog from the saprobe Neurospora crassa to the ?nps6 strain of C. heterostrophus restored wild-type virulence to maize and tolerance to H2O2, demonstrating functional conservation in filamentous ascomycete phytopathogens and saprobes. Increased sensitivity to iron depletion was identified as a conserved phenotype of ?nps6 strains. Exogenous application of iron enhanced the virulence of ?nps6 strains of C. heterostrophus, C. miyabeanus, F. graminearum, and A. brassicicola to each host. NPS6 is responsible for the biosynthesis of extracellular siderophores by C. heterostrophus, F. graminearum, and A. brassicicola. Application of the extracellular siderophore of A. brassicicola restored wild-type virulence of the ?Abnps6 strain to Arabidopsis. It is proposed that the role of extracellular siderophores in fungal virulence to plants is to supply an essential nutrient, iron, to their producers in planta and not to act as phytotoxins, depriving their hosts of iron.

Oide, Shinichi; Moeder, Wolfgang; Krasnoff, Stuart; Gibson, Donna; Haas, Hubertus; Yoshioka, Keiko; Turgeon, B. Gillian

2006-01-01

364

The pleiotropic nature of symbiotic regulatory mutants: Bradyrhizobium japonicum nifA gene is involved in control of nif gene expression and formation of determinate symbiosis.  

PubMed

In the slow-growing soybean symbiont, Bradyrhizobium japonicum (strain 110), a nifA-like regulatory gene was located immediately upstream of the previously mapped fixA gene. By interspecies hybridization and partial DNA sequencing the gene was found to be homologous to nifA from Klebsiella pneumoniae and Rhizobium meliloti, and to a lesser extent, also to ntrC from K. pneumoniae. The B. japonicum nifA gene product was shown to activate B. japonicum and K. pneumoniae nif promoters (using nif::lacZ translational fusions) both in Escherichia coli and B. japonicum backgrounds. In the heterologous E. coli system activation was shown to be dependent on the ntrA gene product. Site-directed insertion and deletion/replacement mutagenesis revealed that nifA is probably the promoter-distal cistron within an operon. NifA- mutants were Fix- and pleiotropic: (i) they were defective in the synthesis of several proteins including the nifH gene product (nitrogenase Fe protein); the same proteins had been known to be repressed under aerobic growth of B. japonicum but derepressed at low O2 tension; (ii) the mutants had an altered nodulation phenotype inducing numerous, small, widely distributed soybean nodules in which the bacteroids were subject to severe degradation. These results show that nifA not only controls nitrogenase genes but also one or more genes involved in the establishment of a determinate, nitrogen-fixing root nodule symbiosis. PMID:15966104

Fischer, H M; Alvarez-Morales, A; Hennecke, H

1986-06-01

365

Disulfide bond involvement in the maintenance of the cryptic nature of the cross-reacting determinant of metacyclic forms of Trypanosoma congolense  

SciTech Connect

The variable surface glycoprotein (VSG) of African trypanosomes possesses a 1,2-dimyristoylglycosylphosphatidylinositol at the carboxy terminus. Cleavage of the 1,2-dimyristoylglycerol (1,2-DMG) moiety from the VSG reportedly results in a higher apparent molecular mass and an increased binding of antibodies against the cross-reacting determinant (CRD), a cryptic epitope present on most VSGs. Using metacyclic forms of Trypanosoma congolense, the authors show that the process involved are more complex than heretofore presumed and that the removal of the 1,2-DMG moiety may not be necessary for binding of anti-CRD antibodies (RxCRD). Among other findings, they observe the following: (1) in sonicated samples of trypanosomes metabolically labeled with ({sup 3}H)myristate, the binding of RxCRD on Western blots is coincident with bands containing labeled (membrane form) VSGs; (2) disulfide reduction of trypanosome sonicates suffices to promote RxCRD binding in the presence or absence of inhibitors of a glycosylphosphatidylinositol-specific phospholipase C; (3) trypanosomes directly solubilized in detergents show quantitative and qualitative differences in RxCRD binding which depend upon the detergent used and the order of addition of disulfide reducing agents. The authors conclude that the binding of RxCRD to T. congolense metacyclic VSGs depends upon the degree of unfolding of the molecule and is clearly a complex, multistep process in which structural changes and disulfide reduction play pivotal roles.

Fish, W.R.; Muriuki, C.W.; Muthiani, A.M.; Grab, D.J.; Lonsdale-Eccles, J.D. (International Laboratory for Research on Animal Diseases, Nairobi (Kenya))

1989-06-27

366

Uranium-mill-tailings remedial-action project (UMTRAP) cover and liner technology development project  

SciTech Connect

Cover and liner systems for uranium mill tailings in the United States must satisfy stringent requirements regarding long-term stability, radon control, and radionuclide and hazardous chemical migration. The cover placed over a tailings pile serves three basic purposes: (1) to reduce the release of radon, (2) to prevent the intrusion of plant roots and burrowing animals into the tailings, and (3) to limit surface erosion. The liner placed under a tailings pile prevents the migration of radionuclides and hazardous chemicals to groundwater. Pacific Northwest Laboratory is developing and evaluating cover and liner systems that meet these objectives and conform to federal standards. The cover and liner technology discussed in this paper involves: (1) single and multilayer earthen cover systems, (2) asphalt emulsion radon barrier systems, (3) biobarrier systems, (4) revegetation and rock covers, and (5) asphalt, clay, and synthetic liner systems. These systems have been tested at the Grand Junction, Colorado, tailings pile, where they have been shown to effectively reduce radon releases and radionuclide and chemical migration.

Hartley, J.N.; Gee, G.W.; Freeman, H.D.; Cline, J.F.; Beedlow, P.A.; Buelt, J.L.; Relyea, J.R.; Tamura, T.

1982-01-01

367

Project Charter (MSA-143). [Uranium Mill Tailings Remedial Action (UMTRA) Project  

SciTech Connect

Public Law 95-604, The Uranium Mill Tailings Radiation Control Act of 1978'' as amended assigns to DOE, other Federal agencies, and involved States and Indian tribes, responsibilities for remedial actions at 22 inactive uranium mill tailings sites listed in the Act, and for any other sites designated by the Secretary prior to November 8, 1979. The objective of the UMTRA Project is to provide remedial action at the mill tailings sites and associated vicinity properties in order to stabilize and control the tailings in a safe and environmentally sound manner and to eliminate potential health hazards caused by residual levels of uranium decay products that exceed EPA standards. A total of 24 uranium mill tailings sites. This Project Charter delineates the respective responsibilities and authorities of (The Office of Nuclear Energy) (NE) and (Albuquerque Operations Office) (AL), and defines the terms and conditions for management of the UMTRA Project. Supplementary Project management documents which have been and are being developed pursuant to this Charter include a Project Plan (PP), a Project Management Plan (PMP) and other plans governing the accomplishment of the Project mission Evolution of the program will require updates of the Project Plan and Project Management Plan.

Not Available

1986-07-01

368

Uranium Mill Tailings Remedial Action Project surface project management plan.  

National Technical Information Service (NTIS)

This Project Management Plan describes the planning, systems, and organization that shall be used to manage the Uranium Mill Tailings Remedial Action Project (UMTRA). US DOE is authorized to stabilize and control surface tailings and ground water contamin...

1994-01-01

369

Insights into head-tailed viruses infecting extremely halophilic archaea.  

PubMed

Extremophilic archaea, both hyperthermophiles and halophiles, dominate in habitats where rather harsh conditions are encountered. Like all other organisms, archaeal cells are susceptible to viral infections, and to date, about 100 archaeal viruses have been described. Among them, there are extraordinary virion morphologies as well as the common head-tailed viruses. Although approximately half of the isolated archaeal viruses belong to the latter group, no three-dimensional virion structures of these head-tailed viruses are available. Thus, rigorous comparisons with bacteriophages are not yet warranted. In the present study, we determined the genome sequences of two of such viruses of halophiles and solved their capsid structures by cryo-electron microscopy and three-dimensional image reconstruction. We show that these viruses are inactivated, yet remain intact, at low salinity and that their infectivity is regained when high salinity is restored. This enabled us to determine their three-dimensional capsid structures at low salinity to a ?10-Å resolution. The genetic and structural data showed that both viruses belong to the same T-number class, but one of them has enlarged its capsid to accommodate a larger genome than typically associated with a T=7 capsid by inserting an additional protein into the capsid lattice. PMID:23283946

Pietilä, Maija K; Laurinmäki, Pasi; Russell, Daniel A; Ko, Ching-Chung; Jacobs-Sera, Deborah; Butcher, Sarah J; Bamford, Dennis H; Hendrix, Roger W

2013-01-02

370

Insights into Head-Tailed Viruses Infecting Extremely Halophilic Archaea  

PubMed Central

Extremophilic archaea, both hyperthermophiles and halophiles, dominate in habitats where rather harsh conditions are encountered. Like all other organisms, archaeal cells are susceptible to viral infections, and to date, about 100 archaeal viruses have been described. Among them, there are extraordinary virion morphologies as well as the common head-tailed viruses. Although approximately half of the isolated archaeal viruses belong to the latter group, no three-dimensional virion structures of these head-tailed viruses are available. Thus, rigorous comparisons with bacteriophages are not yet warranted. In the present study, we determined the genome sequences of two of such viruses of halophiles and solved their capsid structures by cryo-electron microscopy and three-dimensional image reconstruction. We show that these viruses are inactivated, yet remain intact, at low salinity and that their infectivity is regained when high salinity is restored. This enabled us to determine their three-dimensional capsid structures at low salinity to a ?10-Å resolution. The genetic and structural data showed that both viruses belong to the same T-number class, but one of them has enlarged its capsid to accommodate a larger genome than typically associated with a T=7 capsid by inserting an additional protein into the capsid lattice.

Pietila, Maija K.; Laurinmaki, Pasi; Russell, Daniel A.; Ko, Ching-Chung; Jacobs-Sera, Deborah; Butcher, Sarah J.

2013-01-01

371

Approximating M\\/G\\/1 Waiting Time Tail Probabilities  

Microsoft Academic Search

We propose a new approximation formula for the waiting time tail probability of the M\\/G\\/1 queue with FIFO discipline and unlimited waiting space. The aim is to address the difficulty of obtaining good estimates when the tail probability has non-exponential asymptotics. We show that the waiting time tail probability can be expressed in terms of the waiting time tail probability

T. Sakurai

2004-01-01

372

Three Cases with Different Types of Short-Tailed Spermatozoa  

Microsoft Academic Search

Short-tailed spermatozoa were found in 3 men attending our subfertility clinic. Light microscopy revealed basically normal sperm heads, but a short tail was found in 90% or more of the spermatozoa. Scanning and transmission electron-microscopic examinations of the ejaculate revealed several types of short-tailed spermatozoa. In one case, the majority of the spermatozoa had a short, thick tail. In another

K. Ohmori; T. Matsuda; Y. Horii; O. Yoshida

1993-01-01

373

True vestigeal tail with lumbosacral meningomyelocoel: a rare case report.  

PubMed

A human tail is a rare congenital anomaly with a prominent lesion from the lumbosacro-coccygeal region. It is usually classified either as a true tail or as a pseudo-tail. All the lumbosacro-coccygeal protrusions without the evidence of mesenchymal tissue are classified as pseudo-tail. The association of this rare vestigial entity along with meningomyelocele is rarer still. PMID:20868247

Akhil, Prakash; Ashutosh, Niranjan; Fais, Fiages; Shashank, Mishra; Sanjay, Pandey; Singhal, B M; Attri, P C; Arvind, Gupta

2010-10-01

374

Tail reconnection, from Earth to Jupiter to Saturn  

Microsoft Academic Search

Reconnection is an important magnetospheric process that energizes and transports plasmas. Studies of the terrestrial magnetosphere have shown that tail reconnection plays a critical role in initiating substorms. Discovery of jovian tail reconnection and the associated growth phase indicate the substorm nature of jovian tail dynamic events. The growth phase of jovian substorms is caused by the internal processes, i.e.,

Y. S. Ge; C. T. Russell; J. S. Leisner; H. Y. Wei; M. K. Dougherty; H. J. McAndrews; C. M. Jackman; M. F. Thomsen

2009-01-01

375

14. TIP TOP MINE. TAILINGS LOCATED DIRECTLY WEST FROM TIP ...  

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

14. TIP TOP MINE. TAILINGS LOCATED DIRECTLY WEST FROM TIP TOP HOUSE. ID-31-C-12 WOODEN STRUCTURE IS VISIBLE IN TOP LEFT. CABLES VISIBLE LEFT AND CENTER OF TAILINGS. HOUSE IS JUST OVER APEX OF TAILINGS. CAMERA POINTED EAST. - Florida Mountain Mining Sites, Tip Top Mine, West face Florida Mountain, approximately 150 feet below summit, Silver City, Owyhee County, ID

376

Asphalt emulsion sealing of uranium mill tailings. 1979 annual report  

Microsoft Academic Search

Uranium mill tailings are a source of low-level radiation and radioactive materials that may be released into the environment. Stabilization or disposal of these tailings in a safe and environmentally sound way is necessary to minimize radon exhalation and other radioactive releases. One of the most promising concepts for stabilizing uranium tailings is being investigated at the Pacific Northwest Laboratory:

J. N. Hartley; P. L. Koehmstedt; D. J. Esterl; H. D. Freeman

1980-01-01

377

Asphalt emulsion sealing of uranium mill tailings. 1980 annual report  

Microsoft Academic Search

Studies of asphalt emulsion sealants conducted by the Pacific Northwest Laboratory have demonstrated that the sealants are effective in containing radon and other potentially hazardous material within uranium tailings. The laboratory and field studies have further demonstrated that radon exhalation from uranium tailings piles can be reduced by greater than 99% to near background levels. Field tests at the tailings

J. N. Hartley; P. L Koehmstedt; D. J. Esterl; H. D. Freeman; J. L. Buelt; D. A. Nelson; M. R. Elmore

1981-01-01

378

Application of asphalt emulsion seals to uranium mill tailings  

Microsoft Academic Search

Studies of asphalt emulsion sealants have demonstrated that the sealants are effective in containing radon and other potentially hazardous material within uranium tailings. The laboratory and field studies have further demonstrated that radon exhalation from uranium tailings piles can be reduced by greater than 99% to less than background levels. Field tests at the tailings pile in Grand Junction, Colorado

J. N. Hartley; P. L. Koehmstedt; D. J. Esterl; H. D. Freeman; R. L. Clark

1980-01-01

379

Relationships of tailed phages: a survey of protein sequence identity  

Microsoft Academic Search

Summary Using a multiple alignment program, we surveyed about 150 proteins from 35 tailed phages and calculated identity percentages. Sequence similarities are generally weak, indicating an extensive diversification of tailed phages. Related proteins occur in phages of different morphology and host range. DNA and RNA polymerases, integrases, muramidases, and several other tailed phage proteins appear to be acquired from bacteria.

H.-W. Ackermann; A. Elzanowski; G. Fobo; G. Stewart

1995-01-01

380

Spectrum of human tails: A report of six cases  

PubMed Central

Human tail is a curiosity, a cosmetic stigma and presents as an appendage in the lumbosacral region. Six patients of tail in the lumbosacral region are presented here to discuss the spectrum of presentation of human tails. The embryology, pathology and treatment of this entity are discussed along with a brief review of the literature.

Mukhopadhyay, Biswanath; Shukla, Ram M.; Mukhopadhyay, Madhumita; Mandal, Kartik C.; Haldar, Pankaj; Benare, Abhijit

2012-01-01

381

IMPACT PREDICTION OF THE REACTIVATION OF AN UNUSED TAILINGS DAM  

Microsoft Academic Search

A frequent occurrence in areas with a long history of mining is the reactivation of mine residue deposits. This paper presents an impact prediction study conducted for the reactivation of a gold tailings dam. Two phases of new tailings deposition are proposed. The objective of the study was to assess the potential impact on downstream groundwater quality. The tailings dam

TERRY HARCK; BERNADETTE AZZIE; CATRIONA COYLE; TALITA GERMISHUYSE; RAVI VADAPALLI; ALBERT VAN ZYL

382

Grafted polymer tail\\/loop mixtures differing in chain length  

Microsoft Academic Search

Studies examining the structure of monolayers formed by polymer chains grafted to a surface typically focus on chains attached at one end (tails). Bond fluctuation simulations are performed here to probe monolayers composed of equimolar mixtures of tails and double-grafted loops in which the looped chain length (Nloop) is varied at constant surface density and tail length (Ntail). Loops force

Daniel C. Driscoll; Harpreet S. Gulati; Richard J. Spontak; Carol K. Hall

1999-01-01

383

Tail-induced attraction between nucleosome core particles  

Microsoft Academic Search

We study a possible electrostatic mechanism underlying the compaction of DNA inside the nuclei of eucaryotes: the tail-bridging effect between nucleosomes, the fundamental DNA packaging units of the chromatin complex. As a simple model of the nucleosome we introduce the eight-tail colloid, a charged sphere with eight oppositely charged, flexible, grafted chains that represent the terminal histone tails. We show

F. Mühlbacher; H. Schiessel; C. Holm

2006-01-01

384

Tamarind tree seed dispersal by ring-tailed lemurs.  

PubMed

In Madagascar, the gallery forests of the south are among the most endangered. Tamarind trees (Tamarindus indica) dominate these riverine forests and are a keystone food resource for ring-tailed lemurs (Lemur catta). At Berenty Reserve, the presence of tamarind trees is declining, and there is little recruitment of young trees. Because mature tamarinds inhibit growth under their crowns, seeds must be dispersed away from adult trees if tree recruitment is to occur. Ring-tailed lemurs are likely seed dispersers; however, because they spend much of their feeding, siesta, and sleeping time in tamarinds, they may defecate a majority of the tamarind seeds under tamarind trees. To determine whether they disperse tamarind seeds away from overhanging tamarind tree crowns, we observed two troops for 10 days each, noted the locations of feeding and defecation, and collected seeds from feces and fruit for germination. We also collected additional data on tamarind seedling recruitment under natural conditions, in which seedling germination was abundant after extensive rain, including under the canopy. However, seedling survival to 1 year was lower when growing under mature tamarind tree crowns than when growing away from an overhanging crown. Despite low fruit abundance averaging two fruits/m(3) in tamarind crowns, lemurs fed on tamarind fruit for 32% of their feeding samples. Daily path lengths averaged 1,266 m, and lemurs deposited seeds throughout their ranges. Fifty-eight percent of the 417 recorded lemur defecations were on the ground away from overhanging tamarind tree crowns. Tamarind seeds collected from both fruit and feces germinated. Because lemurs deposited viable seeds on the ground away from overhanging mature tamarind tree crowns, we conclude that ring-tailed lemurs provide tamarind tree seed dispersal services. PMID:21629992

Mertl-Millhollen, Anne S; Blumenfeld-Jones, Kathryn; Raharison, Sahoby Marin; Tsaramanana, Donald Raymond; Rasamimanana, Hantanirina

2011-06-01

385

The Trouble With Tailings: How Alteration Mineralogy can Hinder Quantitative Phase Analysis of Mineral Waste  

NASA Astrophysics Data System (ADS)

Quantitative phase analysis, using the Rietveld method and X-ray powder-diffraction data, has become a standard technique for analysis of mineral waste from mining operations. This method relies upon the availability of well defined crystal structures for all detectable mineral phases in a sample. An even more basic assumption, central to quantitative mineralogy, is that all significant mineral phases can be detected from X-ray diffraction data. This is not always the case, because X-ray amorphous and nanocrystalline mineral phases can develop within geological samples as a result of chemical weathering. The extent of mineral-water interaction to which mine tailings are exposed, during processing and storage, makes these materials particularly susceptible to weathering and alteration. We have used the Rietveld method and X-ray powder-diffraction data to quantify the uptake of atmospheric CO2 into secondary carbonate minerals at two operating mines: the Diavik Diamond Mine, Northwest Territories, Canada, and the Mount Keith Nickel Mine, Western Australia, Australia. At Diavik, nominally anhydrous minerals in kimberlitic mine tailings have been found to contain X-ray amorphous material and hydroxyl groups detectable by Raman spectroscopy. A series of weighed mixtures, prepared to simulate kimberlite mine tailings, has been used to assess the effects of X-ray amorphous material on quantitative phase analysis of Diavik tailings. At Mount Keith, hydrated sulphate minerals and halide minerals develop efflorescent crusts at the surface of the tailings storage facility. Hydrated sulphate minerals in these mine tailings commonly decompose to amorphous substances rather than dehydrating to produce minerals detectable from X-ray powder-diffraction patterns. Nanocrystalline and X-ray amorphous material in mine tailings can affect the accuracy of quantitative determinations of CO2 trapping and abundances of sulphur-bearing minerals associated with redox reactions. Here we assess the impact of amorphous material on quantitative X-ray diffraction results with particular reference to CO2 sequestration and suggest strategies for detection and analysis.

Wilson, S. A.; Mills, S. J.; Dipple, G. M.; Raudsepp, M.

2009-05-01

386

Sharp-tailed Grouse Restoration; Colville Tribes Restore Habitat for Sharp-tailed Grouse, Annual Report 2002-2003.  

SciTech Connect

Columbian Sharp-Tailed Grouse (Tympanuchus phasianellus columbianus) (CSTG) are an important traditional and cultural species to the Colville Confederated Tribes (CCT), Spokane Tribe of Indians (STOI), and other Tribes in the Region. They were once the most abundant upland bird in the Region. Currently, the largest remaining population in Washington State occurs on the CCT Reservation in Okanogan County. Increasing agricultural practices and other land uses has contributed to the decline of sharp-tail habitat and populations putting this species at risk. The decline of this species is not new (Yokum, 1952, Buss and Dziedzic, 1955, Zeigler, 1979, Meints 1991, and Crawford and Snyder 1994). The Tribes (CCT and STOI) are determined to protect, enhance and restore habitat for this species continued existence. When Grand Coulee and Chief Joseph Hydro-projects were constructed, inundated habitat used by this species was lost forever adding to overall decline. To compensate and prevent further habitat loss, the CCT proposed a project with Bonneville Power Administration (BPA) funding to address this species and their habitat requirements. The projects main focus is to address habitat utilized by the current CSTG population and determine ways to protect, restore, and enhance habitats for the conservation of this species over time. The project went through the NPPC Review Process and was funded through FY03 by BPA. This report addresses part of the current CCT effort to address the conservation of this species on the Colville Reservation.

Whitney, Richard

2004-01-01

387

Evolution to Pathogenicity of the Parvovirus Minute Virus of Mice in Immunodeficient Mice Involves Genetic Heterogeneity at the Capsid Domain That Determines Tropism?  

PubMed Central

Very little is known about the role that evolutionary dynamics plays in diseases caused by mammalian DNA viruses. To address this issue in a natural host model, we compared the pathogenesis and genetics of the attenuated fibrotropic and the virulent lymphohematotropic strains of the parvovirus minute virus of mice (MVM), and of two invasive fibrotropic MVM (MVMp) variants carrying the I362S or K368R change in the VP2 major capsid protein, in the infection of severe combined immunodeficient (SCID) mice. By 14 to 18 weeks after oronasal inoculation, the I362S and K368R viruses caused lethal leukopenia characterized by tissue damage and inclusion bodies in hemopoietic organs, a pattern of disease found by 7 weeks postinfection with the lymphohematotropic MVM (MVMi) strain. The MVMp populations emerging in leukopenic mice showed consensus sequence changes in the MVMi genotype at residues G321E and A551V of VP2 in the I362S virus infections or A551V and V575A changes in the K368R virus infections, as well as a high level of genetic heterogeneity within a capsid domain at the twofold depression where these residues lay. Amino acids forming this capsid domain are important MVM tropism determinants, as exemplified by the switch in MVMi host range toward mouse fibroblasts conferred by coordinated changes of some of these residues and by the essential character of glutamate at residue 321 for maintaining MVMi tropism toward primary hemopoietic precursors. The few viruses within the spectrum of mutants from mice that maintained the respective parental 321G and 575V residues were infectious in a plaque assay, whereas the viruses with the main consensus sequences exhibited low levels of fitness in culture. Consistent with this finding, a recombinant MVMp virus carrying the consensus sequence mutations arising in the K368R virus background in mice failed to initiate infection in cell lines of different tissue origins, even though it caused rapid-course lethal leukopenia in SCID mice. The parental consensus genotype prevailed during leukopenia development, but plaque-forming viruses with the reversion of the 575A residue to valine emerged in affected organs. The disease caused by the DNA virus in mice, therefore, involves the generation of heterogeneous viral populations that may cooperatively interact for the hemopoietic syndrome. The evolutionary changes delineate a sector of the surface of the capsid that determines tropism and that surrounds the sialic acid receptor binding domain.

Lopez-Bueno, Alberto; Segovia, Jose C.; Bueren, Juan A.; O'Sullivan, M. Gerard; Wang, Feng; Tattersall, Peter; Almendral, Jose M.

2008-01-01

388

Size-partitioning of an urban aerosol to identify particle determinants involved in the proinflammatory response induced in airway epithelial cells  

PubMed Central

Background The contribution of air particles in human cardio-respiratory diseases has been enlightened by several epidemiological studies. However the respective involvement of coarse, fine and ultrafine particles in health effects is still unclear. The aim of the present study is to determine which size fraction from a chemically characterized background aerosol has the most important short term biological effect and to decipher the determinants of such a behaviour. Results Ambient aerosols were collected at an urban background site in Paris using four 13-stage low pressure cascade impactors running in parallel (winter and summer 2005) in order to separate four size-classes (PM0.03–0.17 (defined here as ultrafine particles), PM0.17–1 (fine), PM1–2.5(intermediate) and PM2.5–10 (coarse)). Accordingly, their chemical composition and their pro-inflammatory potential on human airway epithelial cells were investigated. Considering isomass exposures (same particle concentrations for each size fractions) the pro-inflammatory response characterized by Granulocyte Macrophage-Colony Stimulating Factor (GM-CSF) release was found to decrease with aerosol size with no seasonal dependency. When cells were exposed to isovolume of particle suspensions in order to respect the particle proportions observed in ambient air, the GM-CSF release was maximal with the fine fraction. In presence of a recombinant endotoxin neutralizing protein, the GM-CSF release induced by particles is reduced for all size-fractions, with exception of the ultra-fine fraction which response is not modified. The different aerosol size-fractions were found to display important chemical differences related to the various contributing primary and secondary sources and aerosol age. The GM-CSF release was correlated to the organic component of the aerosols and especially its water soluble fraction. Finally, Cytochrome P450 1A1 activity that reflects PAH bioavailability varied as a function of the season: it was maximal for the fine fraction in winter and for the ultrafine fraction in summer. Conclusion In the frame of future regulations, a particular attention should thus be paid to the ultrafine/fine (here referred to as PM1) fraction due to their overwhelming anthropogenic origin and predominance in the urban aerosol and their pro-inflammatory potential.

Ramgolam, Kiran; Favez, Olivier; Cachier, Helene; Gaudichet, Annie; Marano, Francelyne; Martinon, Laurent; Baeza-Squiban, Armelle

2009-01-01

389

Student Involvement  

Microsoft Academic Search

The goal of my research was to find out what attracts students to get involved on campus. I wanted to take an in depth look at student involvement and what keeps students engaged in Western Michigan University. I asked students about student organization recruitment and advertising on campus. In addition, I asked students about WMU’s non-academic support services to gain

Brianne E. Miller

2011-01-01

390

AUTUMN FOODS OF WHITE-TAILED DEER  

Microsoft Academic Search

Rumen contents from65 hunter-harvested deer werecollected and analyzed during 1985-86 to estimate the principal autumn foods consumed by white-tailed deer inhabitingthe Ozark Mountains, Arkansas River Valley, and Gulf Coastal Plain regions of Arkansas. Deer in the Ozarks and Coastal Plain fed heavily on woody browse species, which comprised 99% of rumina identified from these 2 regions. Acorns were the primary

THOMAS A. NELSON

391

Tail-Anchored Proteins in Plants  

Microsoft Academic Search

Tail-anchored (TA) proteins are a class of polypeptides integrated into the membrane by a C-terminally located hydrophobic\\u000a sequence which are present in all three domains of life. Proteins of this class lack an N-terminal signal peptide and reach\\u000a their destination within the cell by posttranslational mechanisms. TA proteins perform a variety of essential functions on\\u000a the cytosolic face of cellular

Emanuela Pedrazzini

2009-01-01

392

Universality of Tail Exponents of Price Changes?  

NASA Astrophysics Data System (ADS)

We study the tail exponents of the distribution of logarithmic price changes in financial markets, and investigate the conjecture that they are universal with an exponent near three. Using data from the London Stock Exchange, we construct the empirical distributions of price returns on several different time scales and study their variation as a function of parameters such as trading volume and tick size (the minimal unit of price variation).

Huang, Luwen; Farmer, Doyne

2007-03-01

393

Fatigue rupture of wallaby tail tendons.  

PubMed

Wallaby tail tendons fail after repeated application of stresses much lower than would be needed to break them in a single pull. We show that this a fatigue phenomenon, distinct from the creep rupture that occurs after prolonged application of a constant stress. The two phenomena are disctinguished by experiments in which tensile stress is cycled at different frequencies, ranging from 1 to 50 Hz. PMID:9244805

Wang, X T; Ker, R F; Alexander, R M

1995-03-01

394

Low molecular weight carboxylic acids in oxidizing porphyry copper tailings.  

PubMed

The distribution of low molecular weight carboxylic acids (LMWCA) was investigated in pore water profiles from two porphyry copper tailings impoundments in Chile (Piuquenes at La Andina and Cauquenes at El Teniente mine). The objectives of this study were (1) to determine the distribution of LMWCA, which are interpreted to be the metabolic byproducts of the autotroph microbial community in this low organic carbon system, and (2) to infer the potential role of these acids in cycling of Fe and other elements in the tailings impoundments. The speciation and mobility of iron, and potential for the release of H+ via hydrolysis of the ferric iron, are key factors in the formation of acid mine drainage in sulfidic mine wastes. In the low-pH oxidation zone of the Piuquenes tailings, Fe(III) is the dominant iron species and shows high mobility. LMWCA, which occur mainly between the oxidation front down to 300 cm below the tailings surface at both locations (e.g., max concentrations of 0.12 mmol/L formate, 0.17 mmol/L acetate, and 0.01 mmol/L pyruvate at Piuquenes and 0.14 mmol/L formate, 0.14 mmol/L acetate, and 0.006 mmol/L pyruvate at Cauquenes), are observed at the same location as high Fe concentrations (up to 71.2 mmol/L Fe(II) and 16.1 mmol/L Fe(III), respectively). In this zone, secondary Fe(III) hydroxides are depleted. Our data suggest that LMWCA may influence the mobility of iron in two ways. First, complexation of Fe(III), through formation of bidentate Fe(III)-LMWCA complexes (e.g., pyruvate, oxalate), may enhance the dissolution of Fe(III) (oxy)hydroxides or may prevent precipitation of Fe(III) (oxy)hydroxides. Soluble Fe(III) chelate complexes which may be mobilized downward and convert to Fe(II) by Fe(III) reducing bacteria. Second, monodentate LMWCA (e.g., acetate and formate) can be used by iron-reducing bacteria as electron donors (e.g., Acidophilum spp.), with ferric iron as the electron acceptor. These processes may, in part, explain the low abundances of secondary Fe(III) hydroxide precipitates below the oxidation front and the high concentrations of Fe(II) observed in the pore waters of some low-sulfide systems. The reduction of Fe(III) and the subsequent increase of iron mobility and potential acidity transfer (Fe(II) oxidation can result in the release of H+ in an oxic environment) should be taken in account in mine waste management strategies. PMID:15884343

Dold, Bernhard; Blowes, David W; Dickhout, Ralph; Spangenberg, Jorge E; Pfeifer, Hans-Rudolf

2005-04-15

395

Low-field Tails in EuBCO Vortex Field Distributions: a T-dependence muSR Study*  

NASA Astrophysics Data System (ADS)

Muon-Spin-Rotation (muSR) vortex data ranging from 3.5 K to roomtemperature of EuBa2Cu3O7 have been analyzed using a Maximum-Entropy (ME) technique [1-3]. With a 1-kOe applied field, anomalous low-field tails [1, 4] stretching from about 0.5 kOe to 0.8 kOe are observed for magnetic field distributions below 40 K. The muSR time-histogram data are weighted with a Gaussian filter. The low-field tail in the vortex field distribution is best viewed within a filter-time interval, determined to lie between 0.73 and 0.95 microseconds. As temperature decreases, an increase in the low-field tail intensity is observed. We note, the presence of the low-field tail indicates that extra superconductivity could exist in the CuO-chain layers well below critical temperature. Currently, we are studying the temperature dependence of the low-field tail by fitting the ME transforms with a tail function and two Gaussians (representing the main vortex and grainboundary signals [1]). Fit-analysis results and comparison with YBCO vortex-tail behavior [1, 2] are reported. [1] Santiago et al, Phys Rev B63 132509 (2001); [2] Alves et al, Phys Rev B49 12396 (1994); [3] Cooke et al, Phys Rev B39 2748 (1989); [4] Aslanian et al, Physica C364-365 582 (2001).

Tien, Y.; Ruiz, E. J.; Aslanian, H. H.; Santiago, R. D.; Li, Y.; Boekema, C.

2002-03-01

396

Effects of tail docking using a rubber ring with or without anesthetic on behavior and production of lactating cows.  

PubMed

Production and behavioral measures were recorded to determine the level of stress and pain associated with tail docking adult dairy cows with a rubber ring. The possible advantages of using an epidural anesthetic were also examined. Sixty-four lactating, mixed-parity, Holstein cows were randomly assigned to one of four treatment groups. The treatments were rubber ring docking with epidural anesthetic (RRA), rubber ring docking without anesthetic (RR), control with epidural anesthetic (CA), and control without anesthetic (C). Behavior was examined on d 0, +1, +2, and +6. Milk production and feed intake were monitored. Cows exhibited subtle behavioral changes following application of rubber rings, as well as after epidural administration on d 0 and tail amputation on d +6. After treatment on d 0, the RR, RRA, and CA groups displayed less tail shaking than the C group. The RR and RRA cows continued to exhibit less tail shaking on d +1, +2, and +6. Also on d 0, the RR and RRA groups held their tails in the raised position less than the C and CA groups. After amputation on d +6, the RR and RRA groups spent longer with their tails pressed to their bodies than the C and CA groups. No significant differences in milk production or feed intake were found. Results suggest that tail-docking adult dairy cattle with rubber rings causes, at most, mild discomfort and that there is no benefit in using an epidural anesthetic. However, long-term effects need to be investigated. PMID:12362458

Tom, E M; Duncan, I J H; Widowski, T M; Bateman, K G; Leslie, K E

2002-09-01

397

Multiple Measures of Hand-Use Lateralization in the Ring-Tailed Lemur (Lemur catta )  

Microsoft Academic Search

Evaluated a free-ranging matriline of 13 ring-tailed lemurs (Lemur catta) from videotaped records for lateralized hand use with 2 tasks and 4 measures: food reaching, feeding posture, duration of food holding, and manipulation of food between mouth and hand while eating. Binomial z scores determined 7 lemurs to be left preferent in reaching, 3 right, and 3 ambipreferent. Ideographic analyses

Garrett W. Milliken; Chris Forsythe; Jeanette P. Ward

1989-01-01

398

Estimation of Presettlement Populations of the Black-Tailed Prairie Dog: A Reply  

Microsoft Academic Search

Determination of the historical distribution and abundance of the black-tailed prairie dog (Cynomys ludovicanus) is important as a component of the science underlying decisions on the future management of this species. Clearly, we differ from Knowles and colleagues (2002) in our interpretation of those data (see below). In addition, Knowles et al. (2002) introduce other lines of evidence rather than

Dallas Virchow; Scott E. Hygnstrom

2002-01-01

399

Site and landscape conditions at white-tailed deer\\/vehicle collision locations in Illinois  

Microsoft Academic Search

Motor vehicle collisions with white-tailed deer (Odocoileus virginianus) present several problems including danger to humans, vehicle damage, and deer mortality. Knowledge of factors influencing deer movements onto or across roads and highways may reduce deer\\/vehicle collisions on existing roads, and improve planning for future roads. We used remotely sensed data to determine characteristics associated with high accident areas. Topographic features

Rebecca A. Finder; John L. Roseberry; Alan Woolf

1999-01-01

400

Prediction of cyanide recovery from silver leaching tailings with AVR using multivariable regression analysis  

Microsoft Academic Search

In this study, the tailings of the silver leaching plant, Eti Gumus AS, Turkey, containing high amounts of cyanide were tested to determine optimum recovery of cyanide, using packed columns for volatilization stage of AVR (acidification, volatilization or stripping, reneutralization). All recovery tests were performed in a pilot plant constructed using random packing with column internals and practised for mass

Huseyin Vapur; Oktay Bayat

2007-01-01

401

Parentage in the cooperative breeding system of long-tailed tits, Aegithalos caudatus  

Microsoft Academic Search

In cooperatively breeding birds multiple maternity and paternity of broods is not uncommon, reproduction often being shared among group members as well as with extragroup members. We investigated the extent of extrapair paternity and intraspecific brood parasitism in a population of cooperatively breeding long-tailed tits. Our aim was to determine the frequency and cause of mixed parentage and to investigate

B. J. HATCHWELL; D. J. ROSS; N. CHALINE; M. K. FOWLIE; T. BURKE

2002-01-01

402

Provisioning Rules in Cooperatively Breeding Long-Tailed Tits Aegithalos caudatus: An Experimental Study  

Microsoft Academic Search

In a population of long-tailed tits Aegithalos caudatus all birds attempted to breed monogamously, but some helped to provision the nestlings of another pair if their own breeding attempt failed. An individual's investment rules will determine the fitness consequences of helping for breeders and helpers, and the aim of this study was to examine how individual investment varied with the

B. J. Hatchwell; A. F. Russell

1996-01-01

403

Application of biochar on mine tailings: effects and perspectives for land reclamation.  

PubMed

Mine tailings represent a source of toxic pollutants, mainly heavy metals, which may spread to the surrounding areas. Phytostabilization, a long-term and cost-effective rehabilitation strategy, can be achieved by promoting the establishment of vegetation to reduce the risk of pollutant transfer. In this work, the application of pyrolyzed biomass (biochar) was studied to evaluate the amelioration of the mine tailings properties for potential use as a phytostabilization technology. Four substrates were obtained by mixing the mine tailings from a dumping site in Cave del Predil (NE, Italy) with biochar from orchard prune residues at four dosages (0%, 1%, 5% and 10% biochar in the mine tailings). The physical and chemical properties were determined and the bioavailability and leachability of the contaminants were estimated. The pH, the nutrient retention in terms of cation exchange capacity and the water-holding capacity increased as the biochar content increased in the substrates and the bioavailability of Cd, Pb, Tl and Zn of the mine tailings decreased. The changes promoted by the biochar seem to be in favor of its use on mine wastes to help the establishment of a green cover in a phytostabilization process. PMID:21501855

Fellet, G; Marchiol, L; Delle Vedove, G; Peressotti, A

2011-04-17

404

Physical modeling of marginally stable tailings dams using centrifuge simulation techniques  

SciTech Connect

The stability of a marginally stable tailings dam is investigated using centrifuge simulations and flow and stability analyses. The centrifuge simulations are conducted on Sandia's large radius machine using tailings from a coal mine. Pore pressure measurements and photographic coverage of the phreatic surface permit the determination of the flow field developed in the dam. The simulations investigate the effects of packing density and particle size distribution on the stability of a dam. The results illustrate that an increase in packing density can increase the stability of the embankment and that the addition of slurried fines to the embankment affects stability by changing the properties of the tailings used to construct the dam and by limiting the discharge of water from the reservoir through the dam. For the tailings studied here, the increase in packing density and fines increases the stability of the dam by changing the material properties of the tailings. However, these changes also restrict the flow through the embankment and thereby reduce the stability of the dam by raising the level of both the reservoir and the phreatic surface. The addition of fines into the reservoir dramatically lowers the position of the phreatic surface by restricting the flow of water into the dam. The effect of this decreased flow is to increase the stability of the embankment, if over-topping of the dam does not occur. 14 references, 15 figures, 2 tables.

Sutherland, H.J.; Rechard, R.P.; Heckes, A.A.

1984-02-01

405

Head-tail instability and Landau damping in bunches with space charge  

NASA Astrophysics Data System (ADS)

Head-tail modes in bunches with space charge are studied using particle tracking simulations. The eigenfrequencies and eigenfunctions of transverse coherent oscillations in a Gaussian bunch are determined and compared with theories. A model for an airbag distribution in a barrier potential gives good predictions for the head-tail spectrum and for eigenfunctions in bunches with space charge. Using numerical simulations, space-charge induced Landau damping in a bunch is demonstrated. The damping rates are quantified for different modes and space-charge tune shifts. Finally, the head-tail instability with space charge is studied for the resistive-wall impedance below the mode coupling threshold. Results demonstrate that space-charge induced damping can suppress the instability for moderately strong space charge; instability growth rates saturate at strong space charge, in agreement with theoretical predictions.

Kornilov, V.; Boine-Frankenheim, O.

2010-11-01

406

Hydrodynamic analysis, performance assessment, and actuator design of a flexible tail propulsor in an artificial alligator  

NASA Astrophysics Data System (ADS)

The overall objective of this research is to develop analysis tools for determining actuator requirements and assessing viable actuator technology for design of a flexible tail propulsor in an artificial alligator. A simple hydrodynamic model that includes both reactive and resistive forces along the tail is proposed and the calculated mean thrust agrees well with conventional estimates of drag. Using the hydrodynamic model forces as an input, studies are performed for an alligator ranging in size from 1 cm to 2 m at swimming speeds of 0.3-1.8 body lengths per second containing five antagonistic pairs of actuators distributed along the length of the tail. Several smart materials are considered for the actuation system, and preliminary analysis results indicate that the acrylic electroactive polymer and the flexible matrix composite actuators are potential artificial muscle technologies for the system.

Philen, Michael; Neu, Wayne

2011-09-01

407

Asphalt emulsion sealing of uranium mill tailings. 1979 annual report  

SciTech Connect

Uranium mill tailings are a source of low-level radiation and radioactive materials that may be released into the environment. Stabilization or disposal of these tailings in a safe and environmentally sound way is necessary to minimize radon exhalation and other radioactive releases. One of the most promising concepts for stabilizing uranium tailings is being investigated at the Pacific Northwest Laboratory: the use of asphalt emulsion to contain radon and other potentially hazardous materials in uranium tailings. Results of these studies indicate that radon flux from uranium tailings can be reduced by greater than 99% by covering the tailings with an asphalt emulsion that is poured on or sprayed on (3.0 to 7.0 mm thick), or mixed with some of the tailings and compacted to form an admixture seal (2.5 to 15.2 cm) containing 18 wt % residual asphalt.

Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

1980-06-01

408

A model actin comet tail disassembling by severing  

NASA Astrophysics Data System (ADS)

We use a numerical simulation to model an actin comet tail as it grows from the surface of a small object (a bead) and disassembles by severing. We explore the dependence of macroscopic properties such as the local tail radius and tail length on several controllable properties, namely the bead diameter, the bead velocity, the severing rate per unit length, and the actin gel mesh size. The model predicts an F-actin density with an initial exponential decay followed by an abrupt decay at the edge of the tail, and predicts that the comet tail diameter is constant along the length of the tail. The simulation results are used to fit a formula relating the comet tail length to the control parameters, and it is proposed that this formula offers a means to extract quantitative information on the actin gel mesh size and severing kinetics from simple macroscopic measurements.

Michalski, P. J.; Carlsson, A. E.

2011-08-01

409

Nature of Axial Tail Instability and Bubble-Blob Formation in Near-Earth Plasma Sheet*  

NASA Astrophysics Data System (ADS)

Previous global MHD simulations of substorm events have identified the dynamic presence of an axial tail instability with dawn-dusk symmetry in the near-Earth plasma sheet as a major cause of the initial loss of MHD equilibrium on closed field lines prior to the subsequent magnetic reconnection and substorm expansion onset processes [Raeder et al. 2010; Siscoe et al. 2009]. In this work, energy principle analysis indicates that a two-dimensional thin current sheet configuration in the magnetotail is typically stable to the axial mode within the framework of ideal MHD model. Linear resistive MHD calculations find axial tail instabilities on closed field lines in the generalized Harris sheet configurations. The properties of these instabilities are similar to the axial tail modes observed in the global MHD simulations. The axial tail mode is unstable in regimes of low Lundquist number and regions with small normal component of magnetic field. Mode growth and structure show both similarities and differences in comparison to the linear resistive tearing mode of a one-dimensional Harris sheet. Unlike the conventional tearing mode of Harris sheet, the linear axial tail instability does not involve any reconnection process. Instead, the nature of the mode is dominantly an interchange or slippage process among neighboring flux tubes as facilitated by dissipations such as resistivity. The formation of bubble-blob pairs in pressure and entropy distributions in the near-Earth plasma sheet is shown to be a natural component as well as consequence of this axial instability process. *Supported by NSF grants AGS-0902360 and PHY-0821899. REFERENCES: Raeder, J., P. Zhu, Y. Ge, and G. Siscoe (2010), Open Geospace General Circulation Model simulation of a substorm: Axial tail instability and ballooning mode preceding substorm onset, J. Geophys. Res., 115, A00I16, doi:10.1029/2010JA015876. Siscoe, G. L., M. M. Kuznetsova, and J. Raeder (2009), Search for an onset mechanism that operates for both CMEs and substorms, Ann. Geophys., 27, 31413146.

Zhu, P.; Raeder, J.; Hegna, C. C.; Sovinec, C. R.

2011-12-01

410

C-terminal domains within human MT1 and MT2 melatonin receptors are involved in internalization processes.  

PubMed

Melatonin, a molecule implicated in a variety of diseases, including cancer, often exerts its effects through G-protein-coupled melatonin receptors, MT(1) and MT(2). In this study, we sought to understand further the domains involved in the function and desensitization patterns of these receptors through site-directed mutagenesis. Two mutations were constructed in the cytoplasmic C-terminal tail of each receptor subtype: (i) a cysteine residue in the C-terminal tail was mutated to alanine, thus removing a putative palmitoylation site, and a site possibly required for normal receptor function (MT(1)C7.72A and MT(2)C7.77A) and (ii) the C-terminal tail in the MT(1) and MT(2) receptors was truncated, removing the putative phosphorylation and beta-arrestin binding sites (MT(1)Y7.64 and MT(2)Y7.64). These mutations did not alter the affinity of 2-[(125)I]-iodomelatonin binding to the MT(1) or MT(2) receptors. Using confocal microscopy, it was determined that the putative palmitoylation site (cysteine residue) did not play a role in receptor internalization; however, this residue was essential for receptor function, as determined by 3',5'-cyclic adenosine monophosphate (cAMP) accumulation assays. Truncation of the C-terminal tail of both receptors (MT(1)Y7.64 and MT(2)Y7.64) inhibited internalization as well as the cAMP response, suggesting the importance of the C-terminal tail in these receptor functions. PMID:18341518

Sethi, Shalini; Adams, Wendy; Pollock, John; Witt-Enderby, Paula A

2008-03-14

411

Reactivation and graded axial expression pattern of Wnt-10a gene during early regeneration stages of adult tail in amphibian urodele Pleurodeles waltl.  

PubMed

Adult urodele amphibians such as Pleurodeles waltl are able to regenerate their amputated limbs or tail. The mechanisms implicated in growth control and formation of the blastema are unknown but it has been proposed that regeneration in newts may proceed through reactivation of genes involved in embryonic development. Knowing the role of Wnt genes in the patterning of the primary and secondary axes of the vertebrate embryo, we suspected that some of these genes could be involved in axial pattern during newt tail regeneration. Pwnt-10a gene, cloned from a newt tail regenerate cDNA library, showed an expression pattern compatible with such a role in tail regenerates. Pwnt-10a, which is highly expressed during embryonic development (from gastrula to tailbud-stage) and weakly expressed in the adult tail, is strongly re-expressed during tail regeneration. In the blastemal mesenchyme Pwnt-10a transcripts exhibited a graded distribution along the antero-posterior axis, the mRNA accumulation being maximal in the caudal most part corresponding to the growing zone. These findings strongly support the view that Pwnt-10a may act in cooperation with other factors to control growth and patterning in newt tail regeneration. Until now Wnt-10a was only known to be involved in central nervous system development; our results suggest that this gene may also play a role in other developmental processes. PMID:9022051

Caubit, X; Nicolas, S; Shi, D L; Le Parco, Y

1997-02-01

412

Hydrochemistry at the Falls City Uranium Mine Tailings Remedial Action Project, Karnes County, Texas  

SciTech Connect

Acidic tailings and tailings solutions, created by sulfuric acid processing of uranium ores, were disposed on the outcrop of the Whitsett Formation (Eocene). These solutions have recharged the sandstones of the Whitsett since the 1960s. Previous work found a large, complex, and unexplained pattern of contamination. The present study determined the extent and nature of contamination by (1) characterizing the geology and hydrology of the two shallow aquifers at the site, (2) determining the chemistry of the contaminant source (tailings solutions), and (3) identifying geochemical reactions that have altered the composition of contaminant plumes within each aquifer. The tailings solutions are composed of sodium chloride and neutral sulfate salts of aluminum and ammonium, with lesser amounts of iron, calcium, magnesium, potassium, and sodium sulfate. Hydrolysis of aluminum sulfate produces an acid pH (3 to 4). Also, aluminum sulfate is a pH buffer and controls acidity of the tailings solutions. Cation exchange and neutralization by calcite modify the tailings solutions as they migrate through the aquifers. These reactions explain chemical patterns, which delineate five separate contaminant plumes in the aquifers. In the Deweesville Sandstone, cation exchange has removed ammonium from acidic contaminant plumes. However, neutralization is incomplete due to the paucity of calcite in the Deweesville. In contrast, in the calcite-rich Conquista fossiliferous sandstone, cation exchange and complete neutralization by calcite have removed most contaminant ions. Those contaminant plumes are delineated by elevated concentrations of calcium and carbon dioxide. The amount of contamination in both aquifers is much smaller than earlier estimated.

Jackson, T.J.; Kreitler, C.W. [Univ. of Texas, Austin, TX (United States)

1994-09-01

413

Flexible Histone Tails in a New Mesoscopic Oligonucleosome Model  

PubMed Central

We describe a new mesoscopic model of oligonucleosomes that incorporates flexible histone tails. The nucleosome cores are modeled using the discrete surface-charge optimization model, which treats the nucleosome as an electrostatic surface represented by hundreds of point charges; the linker DNAs are treated using a discrete elastic chain model; and the histone tails are modeled using a bead/chain hydrodynamic approach as chains of connected beads where each bead represents five protein residues. Appropriate charges and force fields are assigned to each histone chain so as to reproduce the electrostatic potential, structure, and dynamics of the corresponding atomistic histone tails at different salt conditions. The dynamics of resulting oligonucleosomes at different sizes and varying salt concentrations are simulated by Brownian dynamics with complete hydrodynamic interactions. The analyses demonstrate that the new mesoscopic model reproduces experimental results better than its predecessors, which modeled histone tails as rigid entities. In particular, our model with flexible histone tails: correctly accounts for salt-dependent conformational changes in the histone tails; yields the experimentally obtained values of histone-tail mediated core/core attraction energies; and considers the partial shielding of electrostatic repulsion between DNA linkers as a result of the spatial distribution of histone tails. These effects are crucial for regulating chromatin structure but are absent or improperly treated in models with rigid histone tails. The development of this model of oligonucleosomes thus opens new avenues for studying the role of histone tails and their variants in mediating gene expression through modulation of chromatin structure.

Arya, Gaurav; Zhang, Qing; Schlick, Tamar

2006-01-01

414

Quantification of abiotic reaction rates in mine tailings: evaluation of treatment methods for eliminating iron- and sulfur-oxidizing bacteria.  

PubMed

Effective treatment techniques for eliminating iron-oxidizing (IOB) and sulfur-oxidizing bacteria (SOB) are required for the comparison of abiotic and microbial sulfide oxidation rates and mechanisms in mine tailings. This study evaluates the effect of autoclaving, repeated heating, ethanol treatment, antibiotic treatment, gamma-radiation, and washing with deionized water on tailings characteristics and concentrations of IOB and SOB. Most probable number enumeration indicates that IOB and SOB were present at very low concentrations or below detection limits following treatment with all methods except rinsing and antibiotics treatment, where higher concentrations of IOB and SOB were present. The physical, chemical, and mineralogical characterization of the tailings indicated no changes in bulk mineralogy or bulk chemical composition as a result of treatment. However, an increase in oxidized sulfur species at the tailings surface, as determined by X-ray photoelectron spectroscopy, was observed for the heating, autoclaving, and antibiotics treatments. Batch weathering experiments, used to evaluate the effect of treatment on element release rates, indicated that the final element release rates (after >30 d) were similar between treated and untreated control samples. On the basis of the results of this study, experiments over relatively long periods (>30 d) are to be recommended forthe establishment of microbial and abiotic weathering rates in mill tailings samples. For the determination of abiotic reaction rates, treatment by gamma-radiation is suggested to be the most appropriate method for sulfide-rich tailings. PMID:15757338

Herbert, Roger B; Malmström, Maria; Ebenå, Gustav; Salmon, Ursula; Ferrow, Embaie; Fuchs, Matthias

2005-02-01

415

High-velocity tails on the velocity distribution of solar wind ions  

SciTech Connect

Recent observations of the solar wind using the SWICS instrument on the Ulysses spacecraft have shown the presence of high-velocity [open quotes]tails[close quotes] on the velocity distribution of protons. Similar features have also been observed on the velocity distributions of helium and oxygen ions. Of the order of 1% of the solar wind density is involved in these tails, which are approximately exponential in shape and persist to V = V[sub B] + 10V[sub th] or beyond, where V[sub B] is the bulk velocity and V[sub th] the thermal velocity of the solar wind. This paper contains a preliminary description of the phenomenon. It is clear that it is ultimately connected with the passage of interplanetary shocks past the spacecraft and that particle acceleration at oblique shocks is involved. 21 refs., 6 figs., 2 tabs.

Ogilvie, K.W. (Goddard Space Flight Center, Greenbelt, MD (United States)); Geiss, J. (Univ. of Bern (Swaziland)); Gloeckler, G. (Univ. of Maryland, College Park (United States)); Berdichevsky, D. (Highes-STX, Lanham, MD (United States)); Wilken, B. (Max-Plank-Institut fuer Aeronomie Katlenburg-Lindau (Germany))

1993-03-01

416

Genetic linkage analysis using pooled DNA and infrared detection of tailed STRP primer patterns  

NASA Astrophysics Data System (ADS)

The mapping of a disease locus to a specific chromosomal region is an important step in the eventual isolation and analysis of a disease causing gene. Conventional mapping methods analyze large multiplex families and/or smaller nuclear families to find linkage between the disease and a chromosome marker that maps to a known chromosomal region. This analysis is time consuming and tedious, typically requiring the determination of 30,000 genotypes or more. For appropriate populations, we have instead utilized pooled DNA samples for gene mapping which greatly reduces the amount of time necessary for an initial chromosomal screen. This technique assumes a common founder for the disease locus of interest and searches for a region of a chromosome shared between affected individuals. Our analysis involves the PCR amplification of short tandem repeat polymorphisms (STRP) to detect these shared regions. In order to reduce the cost of genotyping, we have designed unlabeled tailed PCR primers which, when combined with a labeled universal primer, provides for an alternative to synthesizing custom labeled primers. The STRP pattern is visualized with an infrared fluorescence based automated DNA sequencer and the patterns quantitated by densitometric analysis of the allele pattern. Differences in the distribution of alleles between pools of affected and unaffected individuals, including a reduction in the number of alleles in the affected pool, indicate the sharing of a region of a chromosome. We have found this method effective for markers 10 - 15 cM away from the disease locus for a recessive genetic disease.

Oetting, William S.; Wildenberg, Scott C.; King, Richard A.

1996-04-01

417

Induction and patterning of trunk and tail neural ectoderm by the homeobox gene eve1 in zebrafish embryos.  

PubMed

In vertebrates, Evx homeodomain transcription factor-encoding genes are expressed in the posterior region during embryonic development, and overexpression experiments have revealed roles in tail development in fish and frogs. We analyzed the molecular mechanisms of posterior neural development and axis formation regulated by eve1. We show that eve1 is involved in establishing trunk and tail neural ectoderm by two independent mechanisms: First, eve1 posteriorizes neural ectoderm via induction of aldh1a2, which encodes an enzyme that synthesizes retinoic acid; second, eve1 is involved in neural induction in the posterior ectoderm by attenuating BMP expression. Further, eve1 can restore trunk neural tube formation in the organizer-deficient ichabod(-/-) mutant. We conclude that eve1 is crucial for the organization of the antero-posterior and dorso-ventral axis in the gastrula ectoderm and also has trunk- and tail-promoting activity. PMID:20142486

Cruz, Carlos; Maegawa, Shingo; Weinberg, Eric S; Wilson, Stephen W; Dawid, Igor B; Kudoh, Tetsuhiro

2010-02-08

418

Diffusion, Peer Pressure, and Tailed Distributions  

NASA Astrophysics Data System (ADS)

We present a general, physically motivated nonlinear and nonlocal advection equation in which the diffusion of interacting random walkers competes with a local drift arising from a kind of peer pressure. We show, using a mapping to an integrable dynamical system, that on varying a parameter the steady-state behavior undergoes a transition from the standard diffusive behavior to a localized stationary state characterized by a tailed distribution. Finally, we show that recent empirical laws on economic growth can be explained as a collective phenomenon due to peer pressure interaction.

Cecconi, Fabio; Marsili, Matteo; Banavar, Jayanth R.; Maritan, Amos

2002-08-01

419

HERA BEAM TAIL SHAPING BY TUNE MODULATION.  

SciTech Connect

To study CP violation, the HEM-B experiment uses an internal wire target in the transverse halo of the stored HERA proton beam. Operational experience shows that the resulting interaction rates are extremely sensitive to tiny orbit jitter amplitudes. Various methods have been studied to stabilize these interaction rates by increasing diffusion in the transverse proton beam tails without affecting the luminosity at the electron-proton collider experiments ZEUS and H1. Tune modulation was found to be a promising method for this task. Experiments performed in recent years will be reported.

MONTAG,C.

2003-05-19

420

Energy metabolism and hematology of white-tailed deer fawns  

USGS Publications Warehouse

Resting metabolic rates, weight gains and hematologic profiles of six newborn, captive white-tailed deer (Odocoileus virginianus) fawns (four females, two males) were determined during the first 3 mo of life. Estimated mean daily weight gain of fawns was 0.2 kg. The regression equation for metabolic rate was: Metabolic rate (kcal/kg0.75/day) = 56.1 +/- 1.3 (age in days), r = 0.65, P less than 0.001). Regression equations were also used to relate age to red blood cell count (RBC), hemoglobin concentration (Hb), packed cell volume, white blood cell count, mean corpuscular volume, mean corpuscular hemoglobin concentration (MCHC), and mean corpuscular hemoglobin. The age relationships of Hb, MCHC, and smaller RBC's were indicative of an increasing and more efficient oxygen-carrying and exchange capacity to fulfill the increasing metabolic demands for oxygen associated with increasing body size.

Rawson, R.E.; DelGiudice, G.D.; Dziuk, H.E.; Mech, L.D.

1992-01-01

421

Behavioral and Activity Assessment of Laboratory Mice (Mus musculus) after Tail Biopsy under Isoflurane Anesthesia  

PubMed Central

Contemporary laboratory animal guidance suggests that tail biopsy of laboratory mice can be performed before 21 d of age without anesthesia, whereas older mice must receive anesthesia before biopsy. Our objective was to determine whether administration of isoflurane anesthesia before tail biopsy produced a measurable effect on the behavior of mice (n = 196). We evaluated C57BL/6 and BALB/c mice at 21 to 24 (weaning), 28 to 31 (delayed weaning), and 42 to 45 (adult) d of age. Mice were observed at the time of biopsy and then twice within the first hour after a sham or tail biopsy. Anxiety-like responses were assessed by using an elevated plus-maze. Activity was evaluated remotely for 120 min. Isoflurane did not diminish acute responses to tail biopsy in mice 31 d or younger compared with sham-biopsied animals but had a significant effect in C57BL/6 biopsied adult mice. In addition, mice of all ages and strains that received anesthesia, regardless of biopsy, spent more time in the enclosed maze arms and had decreased activity up to 5 h after isoflurane exposure. Although tail biopsy should be performed in young mice to avoid transection of distal mature vertebrae, our experimental paradigm indicates that isoflurane anesthesia does not appreciably enhance wellbeing over that of mice biopsied without anesthesia at weaning ages. The influence of inhaled isoflurane was demonstrable and indicated that acute and prolonged alterations in anxiety and activity must be considered when interpreting the impact of anesthesia on tail biopsy across various ages and strains of laboratory mice.

Hankenson, F Claire; Braden-Weiss, Gillian C; Blendy, Julie A

2011-01-01

422

Arsenic and heavy metals in native plants at tailings impoundments in Queretaro, Mexico  

NASA Astrophysics Data System (ADS)

Ten native plants species that grow in three tailings dams from Ag, Pb, Cu and Zn mine in Queretaro, Mexico were studied. Total concentrations in tailings were 183-14,660 mg/kg As, 45-308 mg/kg Cd, 327-1754 mg/kg Pb, 149-459 mg/kg Cu and 448-505 mg/kg Zn. In the three tailings dams, the solubility of these elements is low. Tailings in dam 1 are acid generating while tailings in dams 2 and 3 are not acid-generating potential. Plants species that accumulate arsenic and heavy metals was identified; Nicotina glauca generally presented the highest concentrations (92 mg/kg As, 106 mg/kg Cd, 189 mg/kg Pb, 95 mg/kg Cu and 1985 mg/kg Zn). Other species that accumulate these elements are Flaveria pubescens, Tecoma stans, Prosopis Sp, Casuarina Sp and Maurandia antirrhiniflora. Two species were found that accumulates a large amount of metals in the root, Cenchrus ciliaris and Opuntia lasiacantha. Concentrations in soils in which plants grow were 488-5990 mg/kg As, 5-129 mg/kg Cd, 169-3638 mg/kg Pb, 159-1254 mg/kg Cu and 1431-13,488 mg/kg Zn. The Accumulation Factor (AF) determined for plants was less than 1, with exception of N. glauca for Cd. The correlation between arsenic and heavy metals found in soils and plants was low. Knowledge of plant characteristics allows it use in planning the reforestation of tailings dams in controlled manner. This will reduce the risk of potentially toxic elements are integrated into the food chain of animal species.

Santos-Jallath, José; Castro-Rodríguez, Alejandrina; Huezo-Casillas, José; Torres-Bustillos, Luis

423

Comparison of clomipramine and fluoxetine treatment of dogs with tail chasing.  

PubMed

Objective: The aim of the study was to determine the response to treatment with clomipramine and fluoxetine in dogs with tail chasing. Material and methods: Twenty-five client owned dogs with tail chasing were included in this study. Diagnosis of tail chasing was made on the basis of the dog's behavioral history, clinical signs, and results of laboratory parameters. The study had a randomized, placebo-controlled, double-blind design. Dogs were allocated to three groups. During 12 weeks, dogs of one group were given 2mg/kg clomipramine hydrochloride orally, dogs of the second group received 1mg/kg fluoxetine orally and placebo was administered to control dogs. Changes in signs of tail chasing were weekly reported by the owners. Treatment was assessed in four intervals: weeks 1-3, 4-6, 7-9, and weeks 10-12, respectively. Results: German shepherd dogs and Anatolian sheepdogs were overrepresented. In all four intervals improvement of tail chasing did not differ significantly between clomipramine and fluoxetine (p>0.05). Improvement of behavior in the clomipramine group was significantly better than in the placebo group between weeks 1-3 and 4-6 and between weeks 7-9 and 10-12 (p<0.05). Furthermore, there was a significantly better improvement in the fluoxetine group between weeks 7-9 and weeks 10-12 when compared to the placebo group (p<0.05). Conclusion and clinical relevance: Clomipramine and fluoxetine seem to be equally effective in the treatment of tail chasing. Treated dogs responded well to the drugs and both drugs did not show superiority over each other. PMID:22215314

Yalcin, E

2010-01-01

424

Changes in Zinc Speciation with Mine Tailings Acidification in a Semiarid Weathering Environment  

SciTech Connect

High concentrations of residual metal contaminants in mine tailings can be transported easily by wind and water, particularly when tailings remain unvegetated for decades following mining cessation, as is the case in semiarid landscapes. Understanding the speciation and mobility of contaminant metal(loid)s, particularly in surficial tailings, is essential to controlling their phytotoxicities and to revegetating impacted sites. In prior work, we showed that sur