These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Variation in salamander tail regeneration is associated with genetic factors that determine tail morphology.  

PubMed

Very little is known about the factors that cause variation in regenerative potential within and between species. Here, we used a genetic approach to identify heritable genetic factors that explain variation in tail regenerative outgrowth. A hybrid ambystomatid salamander (Ambystoma mexicanum x A. andersoni) was crossed to an A. mexicanum and 217 offspring were induced to undergo metamorphosis and attain terrestrial adult morphology using thyroid hormone. Following metamorphosis, each salamander's tail tip was amputated and allowed to regenerate, and then amputated a second time and allowed to regenerate. Also, DNA was isolated from all individuals and genotypes were determined for 187 molecular markers distributed throughout the genome. The area of tissue that regenerated after the first and second amputations was highly positively correlated across males and females. Males presented wider tails and regenerated more tail tissue during both episodes of regeneration. Approximately 66-68% of the variation in regenerative outgrowth was explained by tail width, while tail length and genetic sex did not explain a significant amount of variation. A small effect QTL was identified as having a sex-independent effect on tail regeneration, but this QTL was only identified for the first episode of regeneration. Several molecular markers significantly affected regenerative outgrowth during both episodes of regeneration, but the effect sizes were small (<4%) and correlated with tail width. The results show that ambysex and minor effect QTL explain variation in adult tail morphology and importantly, tail width. In turn, tail width at the amputation plane largely determines the rate of regenerative outgrowth. Because amputations in this study were made at approximately the same position of the tail, our results resolve an outstanding question in regenerative biology: regenerative outgrowth positively co-varies as a function of tail width at the amputation site. PMID:23843997

Voss, Gareth J; Kump, D Kevin; Walker, John A; Voss, S Randal

2013-01-01

2

D5 dopamine receptor carboxyl tail involved in D5-D2 heteromer formation  

PubMed Central

We have demonstrated that D5 and D2 dopamine receptors exist as heteromers in cells, and determined these receptor interact through amino acids in the cytoplasmic regions of each receptor. Specifically involved in heteromer formation we identified in the carboxyl tail of the D5 receptor three adjacent glutamic acid residues, and in intracellular loop 3 of the D2 receptor two adjacent arginine residues. Any pairing of these three D5 receptor glutamic acids were sufficient for heteromer formation. These identified residues in D5 and D2 receptors are oppositely charged and likely interact by electrostatic interactions. PMID:23318175

O’Dowd, Brian F.; Nguyen, Tuan; Ji, Xiaodong; George, Susan R.

2013-01-01

3

Involvement of a cytoplasmic-tail serine cluster in urotensin II receptor internalization  

PubMed Central

Most G-protein-coupled receptors that undergo agonist-dependent internalization require the presence of specific cytoplasmic-tail residues to initiate interactions with proteins of the endocytic machinery. Here we show that the UT receptor (urotensin II receptor) undergoes internalization, and that specific serine residues of the receptor's cytoplasmic tail participate in this process. We first observed a time-dependent increase in internalization of the UT receptor expressed in COS-7 cells following binding of the agonist urotensin II. This sequestration was significantly reduced in the presence of sucrose, demonstrating that the agonist-activated UT receptor is internalized in part by clathrin-coated pits. Moreover, the sequestered receptor was co-localized in endocytic vesicles with ?-arrestin1 and ?-arrestin2. To assess whether specific regions of the receptor's cytoplasmic tail were involved in internalization, five UT receptor mutants were constructed. In four constructs the receptor's cytoplasmic tail was truncated at various positions (UT?367, UT?363, UT?350 and UT?336), and in the other four adjacent serine residues at positions 364–367 were replaced by Ala (Mut4S). Each mutant, except UT?367, demonstrated a significantly reduced internalization rate, thereby revealing the importance of specific serine residues within the cytoplasmic tail of the UT receptor for its ability to be internalized efficiently. PMID:15458389

2004-01-01

4

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

5

Field determination of sulphide oxidation rates in mine tailings  

NASA Astrophysics Data System (ADS)

A field study was conducted to assess the rates of oxygen consumption in the vadose zone of sulphide mine tailings. Oxygen uptake rates were measured directly at the ground surface and were compared to rates of sulphate production in the tailings profile. A nonreactive tracer gas was also used to assess effective diffusion coefficients in the shallow subsurface. The 26 measurement sites were located within a 0.1 km2 area in tailings with a water table depth ranging from 0.6 m to ponding at the surface. Ambient oxygen consumption rates in the 8-year-old tailings were compared to measurements through 0.2-m-thick covers of the fine sand and 0.2 m layers of fresh tailings replacing oxidized tailings at ground surface. The oxygen flux across the tailings surface ranged from 0.1 to 250 mol O2 m-2 yr-1 for ambient oxidation conditions. Fresh tailings at the surface produced rates that were as much as twice the ambient rates. The 0.2 m fine sand cover lowered rates by a factor of 100 below ambient rates. Sulphate production rates agreed well with oxygen consumption measurements. Independent diffusion flux measurements with a nonreactive gas exhibited an excellent correlation with oxygen uptake fluxes, indicating the dominance of oxygen diffusion in the control of oxidation rates in the tailings. Spatial trends in oxidation rates were consistent with depth to the water table, and temporal changes by as much as a factor of 2 were attributed to a 0.16 m variation in the depth to the water table over a 2-week period. The results of this study support the use of simple Fickian models to evaluate oxygen diffusion and oxidation rates in sulphide tailings.

Elberling, Bo; Nicholson, Ronald V.

6

Survey Techniques for Determining Occupancy of Isolated Wetlands by Round-tailed Muskrats  

Microsoft Academic Search

Neofiber alleni (round-tailed muskrat) is a wetland-associated species of conservation concern restricted to the southeastern United States. This species is relatively unstudied and no standardized procedures exist for determining its distri- bution. We evaluated a survey technique for assessing presence-absence of round- tailed muskrats in small, isolated, freshwater marshes in central Florida. We con- clude that ? 2 trained persons

Robert L. Schooley; Lyn C. Branch

2005-01-01

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

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. PMID:15159276

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

2004-01-01

9

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

10

Newt tail regeneration: a model for gravity-dependent morphogenesis and clues to the molecular mechanisms involved.  

NASA Astrophysics Data System (ADS)

Gravity alterations are widely recognized to influence living systems. They may cause temporary or permanent effects on physiology and development at different levels, from gene expression to morphogenesis. However, the molecular mechanisms underlying these effects are often unclear, and adequate model systems to study them are required. To address this problem we developed a new experimental model of how gravity affects morphogenesis during tail regeneration in the newt Pleurodeles waltl. The effects of increased gravity on newt tail morphogenesis were first documented in two joint Russian-US NASA spaceflight experiments in the Russian Foton-M2 (2005) and Foton-M3 (2007) missions. In these experiments the shape of newt tail regenerate was found to depend on the gravity level, being dorso-ventrally symmetrical in microgravity and in neutrally-buoyant aquarium controls, versus hook-like and bent downward in 1g controls. These 1g controls were conducted in spaceflight habitats using a water-saturated PVA sponge mat. These results were reproducible in multiple spaceflight, and ground laboratory studies, both in the US at NASA ARC and in Russia at IDB RAS, and were characterized in detail using morphometry and histology approaches. The role of hypergravity in shaping morphogenesis was confirmed at NASA ARC with an experiment in the ISS Testbed 8-foot diameter centrifuge operating at 2g. Animals that experienced two-week centrifugation (the period of time used in the Foton flights) developed the same hook-like regenerates as 1g controls, and morphometric analysis revealed no significant difference between 1g and 2g groups, however both were significantly different from aquarium controls. We hypothesize that exposure to 1g or 2g during tail morphogenesis constitutes excessive loading for newts that are adapted to microgravity-like conditions in their aquatic habitat. Because Heat Shock Proteins (HSPs) are stress-induced molecules that respond to a broad variety of factors and are expressed during development, we hypothesized they may play a role newt tail regenerative morphogenesis under altered g-levels. Specifically there is increasing evidence for HSPs expression changes as a result of hyper-and microgravity. HSPs are also expressed throughout regeneration, rather than just after surgery. To test this hypothesis we performed heat shock on intact and regenerating newts and collected tail tissues. In these experiments we observed that some tails had uplifted tips while others mimicked hook-like regenerates at 1g or 2g. These findings suggest that heat shock, and HSPs induction, may be involved in the mechanism responsible for gravity effects on morphogenesis, or at least interact with them. Current work underway is focused on analyzing the expression of mRNA and localization of proteins for two members of the group, Hsp70 and Hsp90. In summary, we developed and characterized a new practical animal model in which gravity mechanostimulation at 1g, versus unloading in aquaria, causes prominent effects on newt tail regenerative morphogenesis. This model can be achieved without the use of a centrifuge, significantly simplifying its research applications. Initial results using this model suggest that induction of HSPs may be involved in gravity regulation of newt tail regenerative morphogenesis. Further research based on this simple model may help to unravel mechanisms of gravity influence relevant not only to newt tail regeneration, but also to a broad range of other biological processes in amphibian models.

Radugina, Elena A.; Almeida, Eduardo; Grigoryan, Eleonora

11

Arg 901 in the AE1 C-terminal tail is involved in conformational change but not in substrate binding.  

PubMed

In our previous paper, we demonstrated that Arg 901 in the C-terminal tail of human AE1 (band 3, anion exchanger 1) had a functional role in conformational change during anion exchange. To further examine how Arg 901 is involved in conformational change, we expressed various Arg 901 mutants and alanine mutants of the C-terminal tail (from Leu 886 to Val 911) on the plasma membrane of Saccharomyces cerevisiae and evaluated the kinetic parameters of sulfate ion transport. As a result, Vmax decreased as the hydrophobicities of the 901st and peripheral hydrophilic residues increased, indicating that the hydrophobicity of the C-terminal residue is involved in the conformational change. We also found the alkali and protease resistance of the C-terminal region after Arg 901 modification with hydroxyphenylglyoxal (HPG) or phenylglyoxal (PG), a hydrophobic reagent. These results suggested that the increased hydrophobicity of the C-terminal region around Arg 901 leads to inefficient conformational change by the newly produced hydrophobic interaction. PMID:22155194

Takazaki, Shinya; Abe, Yoshito; Yamaguchi, Tomohiro; Yagi, Mikako; Ueda, Tadashi; Kang, Dongchon; Hamasaki, Naotaka

2012-03-01

12

Determination of Acid Volatile Sulfides and Chromium Reducible Sulfides in Cu-Zn and Au Mine Tailings  

Microsoft Academic Search

The present study investigated the use of chemical extractions for the determination of acid volatile sulfides (AVS) and chromium\\u000a reducible sulfides (CRS) in sulfidic mine tailings from Au and Cu-Zn mines. The main objectives of the study were to understand\\u000a the factors affecting AVS and CRS extraction in mine tailings and to use the AVS and CRS data as indicator

Tanmay Praharaj; Danielle Fortin

2004-01-01

13

Determination of the solar wind velocity on the basis of observations of the plasma tail of Comet 1976 VI  

Microsoft Academic Search

The position angles of axes of the plasma tail of Comet West 1976 VI relative to the radius vector of the comet were determined from 17 photographic plates of the comet obtained from March 5 to 30, 1976. The solar wind velocity was determined on the basis of these position angles. The velocity at heliographic latitudes of 33-43 deg was

Kh. I. Ibadinov; M. Kh. Rasulova; E. Pittich

1987-01-01

14

Determinants of Pair-Living in Red-Tailed Sportive Lemurs (Lepilemur ruficaudatus)  

PubMed Central

Pair-living and a monogamous mating strategy are rare and theoretically unexpected among mammals. Nevertheless, about 10% of primate species exhibit such a social system, which is difficult to explain in the absence of paternal care. In this study, we investigated the two major hypotheses proposed to explain the evolution of monogamy in mammals, the female defence hypothesis (FDH) and the resource defence hypothesis (RDH), in red-tailed sportive lemurs (Lepilemur ruficaudatus), a nocturnal primate from Madagascar. We analysed behavioural data from eight male–female pairs collected during a 24-mo field study to illuminate the determinants of pair-living in this species. Male and female L. ruficaudatus were found to live in dispersed pairs, which are characterised by low cohesion and low encounter rates within a common home range. Social interactions between pair partners were mainly agonistic and characterised by a complete absence of affiliative interactions – body contact was only observed during mating. During the short annual mating season, males exhibited elevated levels of aggression towards mates, as well as extensive mate guarding and increased locomotor activity. In addition, males were exclusively responsible for the maintenance of proximity between pair partners during this period, and they defended their territories against neighbouring males but not against females. Together, these results point towards the importance of female defence in explaining pair-living in L. ruficaudatus. We discuss the spatial and temporal distribution of receptive females in relation to the female defence strategies of males and suggest possible costs that prevent male red-tailed sportive lemurs from defending more than one female. PMID:23144523

Hilgartner, Roland; Fichtel, Claudia; Kappeler, Peter M; Zinner, Dietmar

2012-01-01

15

Involvement of ?1B-adrenoceptors in the anti-immobility effect of imipramine in the tail suspension test.  

PubMed

Imipramine is a tricyclic antidepressant inhibitor of norepinephrine and serotonin neuronal reuptake. The roles of specific ?1-adrenoceptor subtypes that might be targeted by the increased synaptic levels of noradrenaline induced by imipramine are not well understood. This study investigates the ?1-adrenoceptor subtypes involved in the anti-immobility effect of imipramine in the mouse tail suspension test. The anti-immobility effect of imipramine (32mg/kg, i.p.) was significantly antagonised by the non-subtype-selective ?1-adrenoceptor antagonist prazosin (0.5 and 1.0mg/kg, i.p.). Neither the selective ?1A-adrenoceptor antagonist 5-methyl-3-[3-[3-[4-[2-(2,2,2,-trifluroethoxy)phenyl]-1-piperazinyl]propyl]-2,4-(1H,3H)-pyrimidinedione (RS-100329, 0.5 and 1.0mg/kg) nor the selective ?1D-adrenoceptor antagonist 8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5]decane-7,9-dione dihydrochloride, (BMY-7378, up to 1.0mg/kg, i.p.) affected the anti-immobility effect of imipramine. However, the anti-immobility effect of imipramine was significantly antagonised by the selective ?1B-adrenoceptor antagonist (2S)-4-(4-amino-6,7-dimethoxy-2-quinazolinyl)-2-[[(1,1-dimethylethyl)amino]carbonyl]-1-piperazinecarboxylate (L-765,314). In addition, mice treated only with RS-100329 or BMY-7378, but not with L-765,314, showed reduced immobility times in comparison to mice treated with vehicle. These results indicate that the selective antagonism of ?1A- and ?1D-adrenoceptors results in antidepressant-like effects and that the ?1B-subtype is the main target for the increased levels of noradrenaline caused by imipramine. PMID:25617795

Ribeiro, Carlos Alberto S; Pupo, André S

2015-03-01

16

DETERMINATION OF GENETIC DIVERSITY AND PATERNITY IN THE GRAY-TAILED VOLE (MICROTUS CANICAUDUS) BY RAPD-PCR  

EPA Science Inventory

Genetic relatedness of gray-tailed voles (Microtus canicaudus) was determined by random amplified polymorphic DNA (RAPD). This work is the first reported use of the RAPD method for pedigree analysis of M. canicaudus and demonstrates the feasibility of RAPD for assessing paternity...

17

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

18

Determination of the fatigue life of a helicopter tail rotor transmission subjected to ballistic damage  

Microsoft Academic Search

The aim of this work is to develop a methodology for the evaluation of the ballistic requirements of a helicopter component. The situation studied in the work refers to the possibility of a damaged helicopter performing an emergency manoeuvre and a 30-min return flight after the impact of a 7.62 NATO projectile on a shaft of the tail rotor transmission.

D. Colombo; M. Giglio

2007-01-01

19

Morphogenesis of the T4 tail and tail fibers  

PubMed Central

Remarkable progress has been made during the past ten years in elucidating the structure of the bacteriophage T4 tail by a combination of three-dimensional image reconstruction from electron micrographs and X-ray crystallography of the components. Partial and complete structures of nine out of twenty tail structural proteins have been determined by X-ray crystallography and have been fitted into the 3D-reconstituted structure of the "extended" tail. The 3D structure of the "contracted" tail was also determined and interpreted in terms of component proteins. Given the pseudo-atomic tail structures both before and after contraction, it is now possible to understand the gross conformational change of the baseplate in terms of the change in the relative positions of the subunit proteins. These studies have explained how the conformational change of the baseplate and contraction of the tail are related to the tail's host cell recognition and membrane penetration function. On the other hand, the baseplate assembly process has been recently reexamined in detail in a precise system involving recombinant proteins (unlike the earlier studies with phage mutants). These experiments showed that the sequential association of the subunits of the baseplate wedge is based on the induced-fit upon association of each subunit. It was also found that, upon association of gp53 (gene product 53), the penultimate subunit of the wedge, six of the wedge intermediates spontaneously associate to form a baseplate-like structure in the absence of the central hub. Structure determination of the rest of the subunits and intermediate complexes and the assembly of the hub still require further study. PMID:21129200

2010-01-01

20

Determining the radon exhalation rate from a gold mine tailings dump by measuring the gamma radiation.  

PubMed

The mining activities taking place in Gauteng province, South Africa have caused millions of tons of rocks to be taken from underground to be milled and processed to extract gold. The uranium bearing tailings are placed in an estimated 250 dumps covering a total area of about 7000 ha. These tailings dumps contain considerable amounts of radium and have therefore been identified as large sources of radon. The size of these dumps make traditional radon exhalation measurements time consuming and it is difficult to get representative measurements for the whole dump. In this work radon exhalation measurements from the non-operational Kloof mine dump have been performed by measuring the gamma radiation from the dump fairly accurately over an area of more than 1 km(2). Radon exhalation from the mine dump have been inferred from this by laboratory-based and in-situ gamma measurements. Thirty four soil samples were collected at depths of 30 cm and 50 cm. The weighted average activity concentrations in the soil samples were 308 ± 7 Bq kg(-1), 255 ± 5 Bq kg(-1) and 18 ± 1 Bq kg(-1) for (238)U, (40)K and (232)Th, respectively. The MEDUSA (Multi-Element Detector for Underwater Sediment Activity) ?-ray detection system was used for field measurements. The radium concentrations were then used with soil parameters to obtain the radon flux using different approaches such as the IAEA (International Atomic Energy Agency) formula. Another technique the MEDUSA Laboratory Technique (MELT) was developed to map radon exhalation based on (1) recognising that radon exhalation does not affect (40)K and (232)Th activity concentrations and (2) that the ratio of the activity concentration of the field (MEDUSA) to the laboratory (HPGe) for (238)U and (40)K or (238)U and (232)Th will give a measure of the radon exhalation at a particular location in the dump. The average, normalised radon flux was found to be 0.12 ± 0.02 Bq m(-2) s(-1) for the mine dump. PMID:25461511

Ongori, Joash N; Lindsay, Robert; Newman, Richard T; Maleka, Peane P

2015-02-01

21

TNF-? stimulation inhibits siRNA-mediated RNA interference through a mechanism involving poly-(A) tail stabilization  

Microsoft Academic Search

The control of mRNA stability is a complex biological process that involves numerous factors, including microRNA (miRNA) and short interfering RNA (siRNA). Here, we show that short interfering RNA (siRNA) and microRNA share some similarities in their response to cellular stress. miR16 expedites the degradation of mRNAs containing AU-rich elements (ARE) in their 3? untranslated region (UTR). si20 is an

Johann Mols; Arjen van den Berg; Motoyuki Otsuka; Min Zheng; Jianming Chen; Jiahuai Han

2008-01-01

22

Determinants of Parental Involvement in Early Schooling: Evidence from Japan  

ERIC Educational Resources Information Center

This study examined how demographic and psychological factors shape the involvement of Japanese mothers in their children's education. The five demographic variables studied were family income, maternal education, family size, mothers' employment status, and sex of the child. Three forms of parental cognition were also studied: mothers'…

Holloway, Susan D.; Yamamoto, Yoko; Suzuki, Sawako; Mindnich, Jessica D.

2008-01-01

23

TNF-alpha stimulation inhibits siRNA-mediated RNA interference through a mechanism involving poly-(A) tail stabilization.  

PubMed

The control of mRNA stability is a complex biological process that involves numerous factors, including microRNA (miRNA) and short interfering RNA (siRNA). Here, we show that short interfering RNA (siRNA) and microRNA share some similarities in their response to cellular stress. miR16 expedites the degradation of mRNAs containing AU-rich elements (ARE) in their 3' untranslated region (UTR). si20 is an siRNA designed to target a non-ARE sequence in the TNF 3'UTR. We found that both si20 and miR16/ARE-mediated degradation of mRNAs can be inhibited by stimulating cells with different stresses. By analyzing TNF-alpha stimulation-mediated stabilization of si20- and miR16-targeted mRNA, we show that this stabilization is not caused by modifying si20 and miR16 loading into Ago2 complexes, or mRNA targeting to Ago2, but by inhibiting mRNA deadenylation. This is the first report showing that a specific siRNA-mediated mRNA degradation can be regulated by inflammatory stimuli, and that deadenylation is involved in this siRNA-mediated mRNA decay. PMID:18423387

Mols, Johann; van den Berg, Arjen; Otsuka, Motoyuki; Zheng, Min; Chen, Jianming; Han, Jiahuai

2008-11-01

24

Endoplasmic reticulum KDEL-tailed cysteine endopeptidase 1 of Arabidopsis (AtCEP1) is involved in pathogen defense  

PubMed Central

Programmed cell death (PCD) is a genetically determined process in all multicellular organisms. Plant PCD is effected by a unique group of papain-type cysteine endopeptidases (CysEP) with a C-terminal KDEL endoplasmic reticulum (ER) retention signal (KDEL CysEP). KDEL CysEPs can be stored as pro-enzymes in ER-derived endomembrane compartments and are released as mature CysEPs in the final stages of organelle disintegration. KDEL CysEPs accept a wide variety of amino acids at the active site, including the glycosylated hydroxyprolines of the extensins that form the basic scaffold of the cell wall. In Arabidopsis, three KDEL CysEPs (AtCEP1, AtCEP2, and AtCEP3) are expressed. Cell- and tissue-specific activities of these three genes suggest that KDEL CysEPs participate in the abscission of flower organs and in the collapse of tissues in the final stage of PCD as well as in developmental tissue remodeling. We observed that AtCEP1 is expressed in response to biotic stress stimuli in the leaf. atcep1 knockout mutants showed enhanced susceptibility to powdery mildew caused by the biotrophic ascomycete Erysiphe cruciferarum. A translational fusion protein of AtCEP1 with a three-fold hemaglutinin-tag and the green fluorescent protein under control of the endogenous AtCEP1 promoter (PCEP1::pre-pro-3xHA-EGFP-AtCEP1-KDEL) rescued the pathogenesis phenotype demonstrating the function of AtCEP1 in restriction of powdery mildew. The spatiotemporal AtCEP1-reporter expression during fungal infection together with microscopic inspection of the interaction phenotype suggested a function of AtCEP1 in controlling late stages of compatible interaction including late epidermal cell death. Additionally, expression of stress response genes appeared to be deregulated in the interaction of atcep1 mutants and E. cruciferarum. Possible functions of AtCEP1 in restricting parasitic success of the obligate biotrophic powdery mildew fungus are discussed. PMID:24605116

Höwing, Timo; Huesmann, Christina; Hoefle, Caroline; Nagel, Marie-Kristin; Isono, Erika; Hückelhoven, Ralph; Gietl, Christine

2014-01-01

25

Endoplasmic reticulum KDEL-tailed cysteine endopeptidase 1 of Arabidopsis (AtCEP1) is involved in pathogen defense.  

PubMed

Programmed cell death (PCD) is a genetically determined process in all multicellular organisms. Plant PCD is effected by a unique group of papain-type cysteine endopeptidases (CysEP) with a C-terminal KDEL endoplasmic reticulum (ER) retention signal (KDEL CysEP). KDEL CysEPs can be stored as pro-enzymes in ER-derived endomembrane compartments and are released as mature CysEPs in the final stages of organelle disintegration. KDEL CysEPs accept a wide variety of amino acids at the active site, including the glycosylated hydroxyprolines of the extensins that form the basic scaffold of the cell wall. In Arabidopsis, three KDEL CysEPs (AtCEP1, AtCEP2, and AtCEP3) are expressed. Cell- and tissue-specific activities of these three genes suggest that KDEL CysEPs participate in the abscission of flower organs and in the collapse of tissues in the final stage of PCD as well as in developmental tissue remodeling. We observed that AtCEP1 is expressed in response to biotic stress stimuli in the leaf. atcep1 knockout mutants showed enhanced susceptibility to powdery mildew caused by the biotrophic ascomycete Erysiphe cruciferarum. A translational fusion protein of AtCEP1 with a three-fold hemaglutinin-tag and the green fluorescent protein under control of the endogenous AtCEP1 promoter (PCEP1::pre-pro-3xHA-EGFP-AtCEP1-KDEL) rescued the pathogenesis phenotype demonstrating the function of AtCEP1 in restriction of powdery mildew. The spatiotemporal AtCEP1-reporter expression during fungal infection together with microscopic inspection of the interaction phenotype suggested a function of AtCEP1 in controlling late stages of compatible interaction including late epidermal cell death. Additionally, expression of stress response genes appeared to be deregulated in the interaction of atcep1 mutants and E. cruciferarum. Possible functions of AtCEP1 in restricting parasitic success of the obligate biotrophic powdery mildew fungus are discussed. PMID:24605116

Höwing, Timo; Huesmann, Christina; Hoefle, Caroline; Nagel, Marie-Kristin; Isono, Erika; Hückelhoven, Ralph; Gietl, Christine

2014-01-01

26

Density and distribution of cutaneous sensilla on tails of leopard geckos (Eublepharis macularius) in relation to caudal autotomy.  

PubMed

The lizard tail is well known for its ability to autotomize and regenerate. Physical contact of the tail by a predator may induce autotomy at the location at which the tail is grasped, and upon detachment the tail may undergo violent, rapid, and unpredictable movements that appear to be, to some degree, regulated by contact with the physical environment. Neither the mechanism by which tail breakage at a particular location is determined, nor that by which environmental feedback to the tail is received, are known. It has been suggested that mechanoreceptors (sensilla) are the means of mediation of such activities, and reports indicate that the density of sensilla on the tail is high. To determine the feasibility that mechanoreceptors are involved in such phenomena, we mapped scale form and the size, density, distribution, and spacing of sensilla on the head, body, limbs, and tail of the leopard gecko. This species has a full complement of autotomy planes along the length of the tail, and the postautotomic behavior of its tail has been documented. We found that the density of sensilla is highest on the tail relative to all other body regions examined; a dorsoventral gradient of caudal sensilla density is evident on the tail; sensilla are more closely spaced on the dorsal and lateral regions of the tail than elsewhere and are carried on relatively small scales; and that the whorls of scales on the tail bear a one to one relationship with the autotomy planes. Our results are consistent with the hypotheses of sensilla being involved in determining the site at which autotomy will occur, and with them being involved in the mediation of tail behavior following autotomy. These findings open the way for experimental neurological investigations of how autotomy is induced and how the detached tail responds to external environmental input. PMID:24643900

Russell, Anthony P; Lai, Erica K; Lawrence Powell, G; Higham, Timothy E

2014-09-01

27

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

28

Tolerance to a self-protein involves its immunodominant but does not involve its subdominant determinants.  

PubMed

We have produced transgenic mice expression hen egg-white lysozyme (HEL) under the control of a ubiquitous promoter, so that in transgenic animals, HEL is presumably present in the serum and thymus throughout the period of establishment of the T-cell repertoire. We show that HEL transgenic H-2d mice with HEL blood levels greater than 10 ng/ml are tolerant to HEL as well as to the immunodominant peptide 108-116. Thus, their T lymphocytes do not proliferate in response to the immunodominant peptide 108-116 after in vivo immunization with HEL or peptide 108-116. In contrast, in transgenic mice tolerant to HEL, the state of tolerance to subdominant peptides 1-18 and 74-96 appears variable and highly depended on HEL blood levels. Complete unresponsiveness is seen when HEL serum levels are high, and this unresponsiveness is reached at a lower HEL concentration for peptide 1-18 than for peptide 74-96. Thus, a hierarchy exists among the three peptides (108-116 much greater than 1-18 greater than 74-96) for induction of a response to HEL and for HEL tolerance induction in T cells specific for these peptides. Persistence in the periphery of autoreactive T cells recognizing subdominant peptides of self-proteins, as shown in this transgenic model, indicates that self-tolerance is limited to a subset of dominant self-peptides and suggests a role for T lymphocytes specific for subdominant determinants in autoimmunity. PMID:1370355

Cibotti, R; Kanellopoulos, J M; Cabaniols, J P; Halle-Panenko, O; Kosmatopoulos, K; Sercarz, E; Kourilsky, P

1992-01-01

29

Effects of intragastric nutrients upon simultaneously determined plasma insulin, glucagon, insulin\\/glucagon ratios and glucose in red-tailed hawks, Buteo jamaicensis gmelin  

Microsoft Academic Search

1. Short-term effects (120 min) of an orally intubated amino-acid mixture upon simultaneously-determined plasma insulin, glucagon, I\\/G ratios and glucose levels were studied in five (nonsexed) 24-hr-fasted adults and two immature red-tailed hawks, Buteo jamaicensis Gmelin. For control and comparative purposes the effects of isosmotic saline, free fatty acids (FFA) or mouse pureé (MP) were also determined. 2. Mean preintubation

Merlyn C. Minick; Gary E. Duke; Susan W. Fishman; Rodney B. Harvey

1996-01-01

30

XAFS determination of the chemical form of lead in smelter-contaminated soils and mine tailings: Importance of adsorption processes  

Microsoft Academic Search

The authors investigated smelter-contaminated soils from Evin-Malmaison, Nord-Pas-de-Calais, France, and mine tailings from Leadville, Colorado, U.S.A. Bulk Pb concentrations range from 460 to 1900 ppm in the topsoils at Evin-Malmaison site and from 6000 to 10,000 ppm in the tailings samples from the Leadville site. These concentrations necessarily raise human health and environmental concerns, but bioavailability and chemical lability of

GUILLAUME MORIN; F. Juillot; P. Ildefonse; G. Calas; J. D. Ostergren; GORDON E. BROWN JR

1999-01-01

31

Ferulic acid exerts antidepressant-like effect in the tail suspension test in mice: evidence for the involvement of the serotonergic system.  

PubMed

Ferulic acid (4-hydroxy-3-methoxycinnamic acid) is a phenolic compound present in several plants with claimed beneficial effects in prevention and treatment of disorders linked to oxidative stress and inflammation. In this study, we aimed to verify the possible antidepressant-like effect of acute oral administration of ferulic acid in the forced swimming test (FST) and tail suspension test (TST) in mice. Additionally, the mechanisms involved in the antidepressant-like action and the effects of the association of ferulic acid with the antidepressants fluoxetine, paroxetine, and sertraline in the TST were investigated. Ferulic acid produced an antidepressant-like effect in the FST and TST (0.01-10 mg/kg, p.o.), without accompanying changes in ambulation. The pretreatment of mice with WAY100635 (0.1 mg/kg, s.c., a selective 5-HT(1A) receptor antagonist) or ketanserin (5 mg/kg, i.p., a 5-HT(2A) receptor antagonist) was able to reverse the anti-immobility effect of ferulic acid (0.01 mg/kg, p.o.) in the TST. The combination of fluoxetine (5 mg/kg, p.o.), paroxetine (0.1 mg/kg, p.o.) or sertraline (1 mg/kg, p.o.) with a sub-effective dose of ferulic acid (0.001 mg/kg, p.o.) produced a synergistic antidepressant-like effect in the TST, without causing hyperlocomotion in the open-field test. Taken together, these results demonstrate that ferulic acid exerts antidepressant-like effect in the FST and TST in mice through modulation of the serotonergic system. PMID:22266492

Zeni, Ana Lúcia B; Zomkowski, Andréa Dias E; Maraschin, Marcelo; Rodrigues, Ana Lúcia S; Tasca, Carla I

2012-03-15

32

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

33

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. PMID:8034737

1994-01-01

34

Self-Determination and Student Transition Planning Knowledge and Skills: Predicting Involvement  

ERIC Educational Resources Information Center

Promoting active student involvement in transition planning has become best practice in promoting self-determination. This study examined the contribution of self-determination to transition planning knowledge and skills for 180 students with disabilities. Utilizing multiple regression analyses, the study found that global self-determination was a…

Wehmeyer, Michael L.; Palmer, Susan B.; Soukup, Jane H.; Garner, Nancy W.; Lawrence, Margaret

2007-01-01

35

Tail Buffeting  

NASA Technical Reports Server (NTRS)

An approximate theory of buffeting is here presented, based on the assumption of harmonic disturbing forces. Two cases of buffeting are considered: namely, for a tail angle of attack greater and less than the stalling angle, respectively. On the basis of the tests conducted and the results of foreign investigators, a general analysis is given of the nature of the forced vibrations the possible load limits on the tail, and the methods of elimination of buffeting.

Abdrashitov, G.

1943-01-01

36

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

37

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

38

Structural and functional characterization of ybr137wp implicates its involvement in the targeting of tail-anchored proteins to membranes.  

PubMed

Nearly 5% of membrane proteins are guided to nuclear, endoplasmic reticulum (ER), mitochondrial, Golgi, or peroxisome membranes by their C-terminal transmembrane domain and are classified as tail-anchored (TA) membrane proteins. In Saccharomyces cerevisiae, the guided entry of TA protein (GET) pathway has been shown to function in the delivery of TA proteins to the ER. The sorting complex for this pathway is comprised of Sgt2, Get4, and Get5 and facilitates the loading of nascent tail-anchored proteins onto the Get3 ATPase. Multiple pulldown assays also indicated that Ybr137wp associates with this complex in vivo. Here, we report a 2.8-Å-resolution crystal structure for Ybr137wp from Saccharomyces cerevisiae. The protein is a decamer in the crystal and also in solution, as observed by size exclusion chromatography and analytical ultracentrifugation. In addition, isothermal titration calorimetry indicated that the C-terminal acidic motif of Ybr137wp interacts with the tetratricopeptide repeat (TPR) domain of Sgt2. Moreover, an in vivo study demonstrated that Ybr137wp is induced in yeast exiting the log phase and ameliorates the defect of TA protein delivery and cell viability derived by the impaired GET system under starvation conditions. Therefore, this study suggests a possible role for Ybr137wp related to targeting of tail-anchored proteins. PMID:25288638

Yeh, Yi-Hung; Lin, Tai-Wen; Li, Yi-Chuan; Tung, Jung-Yu; Lin, Cheng-Yuan; Hsiao, Chwan-Deng

2014-12-01

39

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

40

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

41

Molecular players involved in temperature-dependent sex determination and sex differentiation in Teleost fish  

PubMed Central

The molecular mechanisms that underlie sex determination and differentiation are conserved and diversified. In fish species, temperature-dependent sex determination and differentiation seem to be ubiquitous and molecular players involved in these mechanisms may be conserved. Although how the ambient temperature transduces signals to the undifferentiated gonads remains to be elucidated, the genes downstream in the sex differentiation pathway are shared between sex-determining mechanisms. In this paper, we review recent advances on the molecular players that participate in the sex determination and differentiation in fish species, by putting emphasis on temperature-dependent sex determination and differentiation, which include temperature-dependent sex determination and genetic sex determination plus temperature effects. Application of temperature-dependent sex differentiation in farmed fish and the consequences of temperature-induced sex reversal are discussed. PMID:24735220

2014-01-01

42

Planning for multiple mobile robots in dynamic environ ments involves determining the optimal path each robot  

E-print Network

between these robots must be feasible. In many such applications, there exists a need to coordi­ nateAbstract Planning for multiple mobile robots in dynamic environ­ ments involves determining the optimal path each robot should follow to accomplish the goals of the mission, given the current knowledge

Stentz, Tony

43

Sex determination involves synergistic action of SRY and SF1 on a specific Sox9 enhancer  

E-print Network

-specific enhancer in mice, and that it does so along with steroidogenic factor 1 (SF1, encoded by the gene Nr5a1 (Sf cell-specific genes in mice16 . SF1 is first expressed during mouse gonadal development at E9LETTERS Sex determination involves synergistic action of SRY and SF1 on a specific Sox9 enhancer

McQueen, Heather

44

Paraseller meningiomas: incidence of involvement of extracavernous structures as determined by magnetic resonance and computed tomography.  

PubMed

Parasellar meningiomas frequently extend beyond the cavernous sinus into adjacent structures. In order to determine the incidence of involvement of adjacent sites, we retrospectively evaluated the computed tomography and nuclear magnetic resonance scans of 65 consecutive patients with meningiomas invading the cavernous sinus. Thirteen nearby anatomic sites were analyzed for tumor involvement. The sites most frequently involved were the lateral sphenoid sinus wall (93%), the ipsilateral petrous apex (70%), the ipsilateral posterior petrous bone surface (59%), the sella (59%), the intracranial clival surface (44%), and the suprasellar cistern (41%). The sella, clival bone marrow, orbital apex, pterygopalatine fossa, and prestyloid parapharyngeal space were more commonly involved in recurrent tumors. Lesions were also subdivided into five groups according to whether or not they involved only one part of the cavernous sinus (grade 1), two parts of the cavernous sinus (grade 2), surrounded the cavernous carotid artery (grade 3), surrounded and narrowed the cavernous carotid artery (grade 4), or involved both sides of the cavernous sinus (grade 5). Among the 63 cases that could be assigned to a category, seven were grade 1 lesions, 13 were grade 2, 13 were grade 3, 16 were grade 4, and 14 were grade 5. Tumor grade is helpful in predicting the difficulty of resection of the cavernous component of the tumor. The incidence of involvement of adjacent sites is also helpful in assessment of imaging studies and in planning the most appropriate surgical approach. PMID:17170906

Lanzino, G; Hirsch, W L; Pomonis, S; Sekhar, L N

1993-01-01

45

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

2004-04-16

46

Involvement of Androgen Receptor in Sex Determination in an Amphibian Species  

PubMed Central

In mice and humans, the androgen receptor (AR) gene, located on the X chromosome, is not known to be involved in sex determination. In the Japanese frog Rana rugosa the AR is located on the sex chromosomes (X, Y, Z and W). Phylogenetic analysis shows that the AR on the X chromosome (X-AR) of the Korean R. rugosa is basal and segregates into two clusters: one containing W-AR of Japanese R. rugosa, the other containing Y-AR. AR expression is twice as high in ZZ (male) compared to ZW (female) embryos in which the W-AR is barely expressed. Higher AR-expression may be associated with male sex determination in this species. To examine whether the Z-AR is involved in sex determination in R. rugosa, we produced transgenic (Tg) frogs carrying an exogenous Z-AR. Analysis of ZW Tg frogs revealed development of masculinized gonads or ‘ovotestes’. Expression of CYP17 and Dmrt1, genes known to be activated during normal male gonadal development, were up-regulated in the ZW ovotestis. Testosterone, supplied to the rearing water, completed the female-to-male sex-reversal in the AR-Tg ZW frogs. Here we report that Z-AR is involved in male sex-determination in an amphibian species. PMID:24826887

Oike, Akira; Matsuo, Yasuki; Min, Mi-Sook; Hasebe, Takashi; Ishizuya-Oka, Atsuko; Kawakami, Koichi; Nakamura, Masahisa

2014-01-01

47

Involvement of AMPA Receptors in the Antidepressant-Like Effects of Lithium in the Mouse Tail Suspension Test and Forced Swim Test  

PubMed Central

In addition to its clinical antimanic effects, lithium also has efficacy in the treatment of depression. However, the mechanism by which lithium exerts its antidepressant effects is unclear. Our objective was to further characterize the effects of peripheral and central administration of lithium in mouse models of antidepressant efficacy as well as to investigate the role of alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptors in these behaviors. We utilized the mouse forced swim test (FST) and tail suspension test (TST), intracerebroventricular (ICV) lithium administration, AMPA receptor inhibitors, and BS3 crosslinking followed by western blot. Both short- and long-term administration of lithium resulted in robust antidepressant-like effects in the mouse FST and TST. Using ICV administration of lithium, we show that these effects are due to actions of lithium on the brain, rather than to peripheral effects of the drug. Both ICV and rodent chow (0.4% LiCl) administration paradigms resulted in brain lithium concentrations within the human therapeutic range. The effects of lithium to decrease immobility in the FST and TST were blocked by administration of AMPA receptor inhibitors. Additionally, administration of lithium increased the cell surface expression of GluR1 and GluR2 in the mouse hippocampus. Collectively, these data show that lithium exerts centrally mediated antidepressant-like effects in the mouse FST and TST that require AMPA receptor activation. Lithium may exert its antidepressant effects in humans through AMPA receptors, thus further supporting a role of targeting AMPA receptors as a therapeutic approach for the treatment of depression. PMID:18096191

Gould, Todd D.; O’Donnell, Kelley C.; Dow, Eliot R.; Du, Jing; Chen, Guang; Manji, Husseini K.

2008-01-01

48

Molecular flexibility in nematic phases : direct determination of separate molecular core and alkyl tail rotational relaxation times  

E-print Network

plusieurs molécules mésomorphes en phase nématique. Nous avons achevé cette détermination par l'analyse de of infrared absorption bands in ordered fluids to the determination of reorientational correlation timesL-341 Molecular flexibility in nematic phases : direct determination of separate molecular core

Paris-Sud XI, Université de

49

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

PubMed Central

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

2013-01-01

50

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

2013-01-01

51

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. PMID:11805042

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

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. PMID:24130514

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

2013-01-01

53

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

2012-10-20

54

Soil acidity determines the effectiveness of an organic amendment and a native bacterium for increasing soil stabilisation in semiarid mine tailings.  

PubMed

Unstable mine tailings are vulnerable to water and air erosion, so it is important to promote their surface stabilisation in order to avoid the spread of heavy metals. In a greenhouse experiment, we assessed the effect of the addition of Aspergillus niger-treated sugar beet waste and inoculation with a native bacterium, Bacillus cereus, on the stabilisation of soil aggregates of two acidic, semiarid mine tailings, with different acidity degree, during watering and drying periods. Organic amendment raised the pH of both the moderately and highly acidic tailings, whereas the bacterial inoculation increased this parameter in the former. Only the amendment addition increased soil water-soluble carbon in both tailings compared with their controls, under either watering or drying conditions. Both the amendment and B. cereus enhanced water-soluble carbohydrates. Both treatments increased dehydrogenase activity and aggregate stability, particularly in the moderately acidic tailing under drying conditions. After soil drying, aggregate stability was increased by the amendment (about 66% higher than the control soil) and by the bacterium (about 45% higher than the control soil) in the moderately acidic tailing. The effectiveness of these treatments as structure-stabilisation methods for degraded, semiarid mine ecosystems appears to be restricted to tailings of moderate acidity. PMID:18954889

Carrasco, L; Caravaca, F; Azcón, R; Roldán, A

2009-01-01

55

8 CFR 1208.31 - Reasonable fear of persecution or torture determinations involving aliens ordered removed under...  

Code of Federal Regulations, 2013 CFR

8 Aliens and Nationality 1 2013-01-01 2013-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2013-01-01

56

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

Code of Federal Regulations, 2010 CFR

8 Aliens and Nationality 1 2010-01-01 2010-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2010-01-01

57

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

Code of Federal Regulations, 2012 CFR

8 Aliens and Nationality 1 2012-01-01 2012-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2012-01-01

58

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

Code of Federal Regulations, 2013 CFR

8 Aliens and Nationality 1 2013-01-01 2013-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2013-01-01

59

8 CFR 1208.31 - Reasonable fear of persecution or torture determinations involving aliens ordered removed under...  

Code of Federal Regulations, 2011 CFR

8 Aliens and Nationality 1 2011-01-01 2011-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2011-01-01

60

8 CFR 1208.31 - Reasonable fear of persecution or torture determinations involving aliens ordered removed under...  

Code of Federal Regulations, 2012 CFR

8 Aliens and Nationality 1 2012-01-01 2012-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2012-01-01

61

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

Code of Federal Regulations, 2011 CFR

8 Aliens and Nationality 1 2011-01-01 2011-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2011-01-01

62

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

Code of Federal Regulations, 2014 CFR

8 Aliens and Nationality 1 2014-01-01 2014-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2014-01-01

63

8 CFR 1208.31 - Reasonable fear of persecution or torture determinations involving aliens ordered removed under...  

Code of Federal Regulations, 2014 CFR

8 Aliens and Nationality 1 2014-01-01 2014-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2014-01-01

64

8 CFR 1208.31 - Reasonable fear of persecution or torture determinations involving aliens ordered removed under...  

Code of Federal Regulations, 2010 CFR

8 Aliens and Nationality 1 2010-01-01 2010-01-01...fear of persecution or torture determinations involving aliens ordered removed under section 238(b) of the Act and aliens whose removal is reinstated under section...

2010-01-01

65

Ergonomic determinants of back pain in physiotherapists involved in paediatric neurorehabilitation.  

PubMed

Background. Work-related musculoskeletal disorders in physiotherapists working with children are due to the failure to apply the principles of ergonomics in their daily practice, which is often caused by the necessity of working in forced positions. Health hazards are even bigger because of the disproportion of body weight and height between the patient and the therapist. The aim of the study was to evaluate positions of the spine at work among physiotherapists involved in child neurorehabilitation and their impact on the occurrence of back pain. Material and methods. The study enrolled 84 physiotherapists between the ages of 28-55 years involved in child neurorehabilitation whose seniority in the profession ranged from 2 to 33 years. The physiotherapists were interviewed about their work and its negative consequences. The 6-degree Jackson and Moskowitz scale was used to determine the level of pain intensity. Three-dimensional positions of the spine were recorded under natural working conditions using a SonoSens Monitor 8 ultrasonic measuring system. The recorded data was compared with the so-called "profile for ergonomic operation of the spine". The idea behind the study was to find the relation between pain intensity, duration and location on the one hand, and working positions of the spine and other data from the interview on the other. The statistical analysis was based on Spearman's rank correlation coefficient, analysis of variance with single classification, post hoc analysis (Tukey test) and the chi-square test (%2). The level of statistical significance was established at p < 0.05. Results. All subjects reported 1-4° pain. The intensity of pain increased with age, profession seniority, duration of the history of pain and duration of a sense of fatigue persisting after work. Pain intensity correlated with the length of time the spine was placed in unergonomic positions - especially in excessive lateral flexion in the thoracic segment and rotation in the cervical, thoracic and lumbar segments. Conclusions. 1. Positions of the spine in physiotherapists involved in neurorehabilitation of children are unergonomic and back pain is common in these therapists. 2 There is a correlation between working techniques and the prevalence of pain in physiotherapists. PMID:25404630

Czupryna, Krzysztof; Nowotny-Czupryna, Olga; Nowotny, Janusz

2014-08-28

66

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

Code of Federal Regulations, 2010 CFR

...involving stowaways and applicants for admission found inadmissible pursuant to section...involving stowaways and applicants for admission found inadmissible pursuant to section...officers in conducting credible fear interviews and in making positive and...

2010-01-01

67

The determinants of dumping: a national study of economically motivated transfers involving mental health care.  

PubMed Central

OBJECTIVE: To examine the prevalence and determinants of economically motivated transfers (aka "dumping") from hospitals treating mental illness. DATA SOURCES: A composite data set constructed from three national random-sampled surveys conducted in 1988 and 1989: (1) of hospitals providing mental health care, (2) of community mental health centers, and (3) of psychiatrists. STUDY DESIGN: The study uses reports from administrators of community mental health centers (CMHCs) to assess the extent of patient dumping by hospitals. To assess the determinants of dumping, reported perceptions of dumping are regressed on variables describing the catchment area in terms of the proportion of for-profit hospitals, intensity of competition among hospitals, extent of utilization review, and capacity of the local treatment system, as well as competition among community mental health centers. To assess if dumping is motivated by factors distinct from those affecting other aspects of access, comparable regressions are estimated with ease of hospital admission as the dependent variables. PRINCIPAL FINDINGS: Economically motivated transfers of psychiatric patients were widespread in 1988: according to the reports of CMHC administrators, 64.7 percent of all hospitals providing inpatient mental health care engaged in transfers of this sort. The extent of dumping was higher in catchment areas with more competition among hospitals, more proprietary hospitals, and less inpatient capacity in the public sector. Dumping appeared to be more sensitive to capacity in the public sector but less sensitive to involvement by for-profit hospitals than were other measures of access to care. CONCLUSIONS: Economically motivated transfers of patients with mental illness were widespread in 1988 and likely have increased since that time, affecting the viability of the community mental health care system. PMID:9402901

Schlesinger, M; Dorwart, R; Hoover, C; Epstein, S

1997-01-01

68

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

PubMed

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 subfamilies 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 subfamily); EgGLO2 (GLOBOSA subfamily); EgDEF1 (DEFICIENS subfamily); and EgAG2 (AGAMOUS subfamily), are described. In order to determine where and when in the plant these genes are likely to function, their spatial and temporal patterns of expression were studied during the development of male and female inflorescences, either of normal phenotype or displaying a homeotic flowering abnormality known as mantled. In parallel, the phenotypic effects of ectopically expressing these genes in transgenic Arabidopsis thaliana plants were analysed. The data suggest a broad conservation of floral homeotic gene functions between oil palm and previously described model species, although a few minor variations in the zones of activity of certain genes cannot be excluded. The data also indicate distinct molecular identities for the morphologically similar floral organs of whorls 1 and 2. They also reveal reduced expression of putative B, C/D, and E class genes in mantled flowers, which undergo a homeotic transformation comparable to B class mutants of model species. PMID:17339652

Adam, Hélène; Jouannic, Stefan; Orieux, Yves; Morcillo, Fabienne; Richaud, Frédérique; Duval, Yves; Tregear, James W

2007-01-01

69

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

2013-04-01

70

Child with a Tail  

PubMed Central

Spina Bifida occulta usually presents with some cutaneous stigmata e.g. hair patch, sinus, lipoma, hyperpigmented skin and very rarely a congenital tail. A congenital tail may and may not be associated with spina bifida occulta and tethered cord. A four month old male child presented with congenital tail which was associated with spinal dysraphism and caused tethering of the cord itself. The tail and tethering lesion were excised successfully. PMID:24381838

Sandhu, Asif Iqbal; Khan, Feeroz Alam; Ehmed, Ejaz; Dar, Sajid Hameed

2013-01-01

71

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

72

Beyond the histone tail  

PubMed Central

Post-translational modifications (PTMs) of histones have been implicated in cellular processes such as transcription, replication and DNA repair. These processes normally involve dynamic changes in chromatin structure and DNA accessibility. Most of the PTMs reported so far map on the histone tails and essentially affect chromatin structure indirectly by recruiting effector proteins. A recent study by Schneider and colleagues published in Cell1 has uncovered the function of H3K122 acetylation found within the histone globular domain and specifically positioned on the DNA-bound surface of the nucleosome. Their findings demonstrate a direct effect of histone PTMs on chromatin dynamics, and propose that modifications located in different parts of the nucleosome employ distinct regulatory mechanisms. PMID:23941995

Molina-Serrano, Diego; Kirmizis, Antonis

2013-01-01

73

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

74

Biological Essentialism, Gender Ideologies, and Role Attitudes: What Determines Parents’ Involvement in Child Care  

Microsoft Academic Search

This study draws on Bem’s conceptualization (The lenses of gender: Transforming the debate on sexual inequality. New Haven, CT: Yale University Press, 1993) of biological essentialism to explore fathers’ and mothers’ involvement in child care. The relationships between parental\\u000a essentialist perceptions, gender ideology, fathers’ role attitudes, and various forms of involvement in child care were examined.\\u000a Two hundred and nine

Ruth Gaunt

2006-01-01

75

Tissue-Specific Expression of Head-to-Tail Cyclized Miniproteins in Violaceae and Structure Determination of the Root Cyclotide Viola hederacea root cyclotide1  

Microsoft Academic Search

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 connect- ing backbone segments form a loop that is penetrated by the third disulfide bond. This knotted disulfide arrangement, together with the cyclic

Manuela Trabi; David J. Craik

2004-01-01

76

Ubiquitination of ?-integrin cytoplasmic tails  

PubMed Central

Recent findings have shown that ubiquitination is involved in regulating several proteins required for cell adhesion and migration. We showed that ?5 integrin is ubiquitinated at its cytoplasmic lysines in response to fibronectin binding, and that this is required for its sorting to lysosomes together with fibronectin. Here we speculate whether other ? integrin tails may also be ubiquitinated, and discuss the significance of ubiquitin linkages in the regulation of cell adhesion and migration. PMID:21331246

Lobert, Viola Hélène

2010-01-01

77

Effect of Horizontal-Tail Span and Vertical Location on the Aerodynamic Characteristics of an Unswept Tail Assembly in Sideslip  

NASA Technical Reports Server (NTRS)

An investigation has been conducted in the Langley stability tunnel on a vertical-tail model with a stub fuselage in combination with various horizontal tails to determine the effect of horizontal-tail span and vertical location of the horizontal tail relative to the vertical tail on the aerodynamic characteristics of an unswept tail assembly in sideslip. The results of the investigation indicated that the induced loading carried by the horizontal tail produced a rolling moment about the point of attachment to the vertical tail which was strongly influenced by horizontal-tail span and vertical locations. The greatest effect of horizontal-tail span on the rolling-moment derivative of the complete tail assembly was obtained for horizontal-tail locations near the top of the vertical tail. Span loadings which were reduced to the static-stability derivatives were calculated for each configuration tested by applying the well-known finite-step method used for wings to the intersecting surfaces of the vertical and horizontal tails. The finite-step method provides a simple and effective means of investigating the span loadings of intersecting surfaces.

Riley, Donald R

1954-01-01

78

Effect of Fuselage and Tail Surfaces on Low-speed Yawing Characteristics of a Swept-wing Model as Determined in Curved-flow Test Section of Langley Stability Tunnel  

NASA Technical Reports Server (NTRS)

Results are presented of a wind-tunnel investigation made to determine the influence of the fuselage and tail surfaces on the rotary derivatives in yawing flight of a transonic-airplane configuration having 45 degrees sweptback wing and tail surfaces. The tests were run in the curved-flow test section of the Langley stability tunnel at a Reynolds number of 1.07 X 10 to the sixth power and consisted of balance measurements throughout the angle-of-attack range for several flight-path radii of curvature. The results are compared with data from forced-oscillation and free-oscillation tests, and a description of testing techniques used is included.

Bird, John D; Jaquet, Byron M; Cowan, John W

1951-01-01

79

Determinants of maltreatment substantiation in a sample of infants involved with the child welfare system  

Microsoft Academic Search

Children under one year of age are highly vulnerable to child maltreatment, which can lead to serious immediate and long-term physical and mental health consequences. Child welfare workers encounter unique challenges when assessing allegations of maltreatment involving infants. This study identifies correlates of maltreatment substantiation in a sample of 793 infants less than one year of age investigated by child

Gabriela Williams; Lil Tonmyr; Susan M. Jack; Barbara Fallon; Harriet L. MacMillan

2011-01-01

80

Sex determination involves synergistic action of SRY and SF1 on a specific Sox9 enhancer  

Microsoft Academic Search

The mammalian Y chromosome acts as a dominant male determinant as a result of the action of a single gene, Sry, whose role in sex determination is to initiate testis rather than ovary development from early bipotential gonads. It does so by triggering the differentiation of Sertoli cells from supporting cell precursors, which would otherwise give follicle cells. The related

Ryohei Sekido; Robin Lovell-Badge

2008-01-01

81

Planning for multiple mobile robots in dynamic environ-ments involves determining the optimal path each robot  

E-print Network

between these robots must be feasible. In many such applications, there exists a need to coordi- nateAbstract Planning for multiple mobile robots in dynamic environ- ments involves determining the optimal path each robot should follow to accomplish the goals of the mission, given the current knowledge

Stentz, Tony

82

Natural Carbon Sequestration in Mine Tailings  

NASA Astrophysics Data System (ADS)

We have documented active sequestration of atmospheric carbon dioxide (CO2) in chrysotile mine tailings at Clinton Creek, Yukon and Cassiar, British Columbia. Hydrated magnesium carbonate minerals develop in mine tailings as a natural consequence of the weathering process within the residues. Magnesium, leached from minerals, reacts with dissolved CO2 in rainwater, precipitating carbonates at the surface of tailings upon evaporation of pore fluids. Increased reaction rates are observed in the tailings environment due to fine grainsize resulting from mineral processing. Mine tailings may therefore represent the optimal environment in which to pursue mineral sequestration. X-ray powder-diffraction studies demonstrate that CO2 is crystallographically bound within the hydrated magnesium carbonate minerals nesquehonite, dypingite, hydromagnesite, and lansfordite. Quantitative phase analysis with X-ray powder-diffraction is used to determine the modal abundance of hydrated magnesium carbonates in mine tailings. An atmospheric source of CO2 is confirmed with stable and radiogenic carbon isotope techniques. Serpentine and olivine-rich tailings are produced by many types of mining, including nickel, diamond, platinum, and chrysotile. The global scale of these mining activities has a sequestration capacity on the order of 100 million tonnes of carbon per year. Widespread implementation of mineral sequestration in mine tailings has the potential to render large mining operations greenhouse gas-neutral and significantly reduce CO2 emissions on a global scale.

Wilson, S. A.; Dipple, G. M.; Raudsepp, M.; Anderson, R. G.

2005-12-01

83

Mineralogic variations in fluvial sediments contaminated by mine tailings as determined from AVIRIS data, Coeur D'Alene River Valley, Idaho  

NASA Technical Reports Server (NTRS)

The success of imaging spectrometry in mineralogic mapping of natural terrains indicates that the technology can also be used to assess the environmental impact of human activities in certain instances. Specifically, this paper describes an investigation into the use of data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) for mapping the spread of, and assessing changes in, the mineralogic character of tailings from a major silver and base metal mining district. The area under investigation is the Coeur d'Alene River Valley in northern Idaho. Mining has been going on in and around the towns of Kellogg and Wallace, Idaho since the 1880's. In the Kellogg-Smelterville Flats area, west of Kellogg, mine tailings were piled alongside the South Fork of the Coeur d'Alene River. Until the construction of tailings ponds in 1968 much of these waste materials were washed directly into the South Fork. The Kellogg-Smelterville area was declared an Environmental Protection Agency (EPA) Superfund site in 1983 and remediation efforts are currently underway. Recent studies have demonstrated that sediments in the Coeur d'Alene River and in the northern part of Lake Coeur d'Alene, into which the river flows, are highly enriched in Ag, Cu, Pb, Zn, Cd, Hg, As, and Sb. These trace metals have become aggregated in iron oxide and oxyhydroxide minerals and/or mineraloids. Reflectance spectra of iron-rich tailing materials are shown. Also shown are spectra of hematite and goethite. The broad bandwidth and long band center (near 1 micron) of the Fe(3+) crystal-field band of the iron-rich sediment samples combined with the lack of features on the Fe(3+) -O(2-) charge transfer absorption edge indicates that the ferric oxide and/or oxyhydroxide in these sediments is poorly crystalline to amorphous in character. Similar features are seen in poorly crystalline basaltic weathering products (e.g., palagonites). The problem of mapping and analyzing the downriver occurrences of iron rich tailings in the Coeur d'Alene (CDA) River Valley using remotely sensed data is complicated by the full vegetation cover present in the area. Because exposures of rock and soil were sparse, the data processing techniques used in this study were sensitive to detecting materials at subpixel scales. The methods used included spectral mixture analysis and a constrained energy minimization technique.

Farrand, W. H.; Harsanyi, Joseph C.

1995-01-01

84

Geomorphic criteria for selecting stable uranium tailings disposal sites in New Mexico. Volume 1. Technical report. Final report  

Microsoft Academic Search

Essential to the disposal of uranium mill tailings in northwestern New Mexico is the geomorphic stability of the disposal site. Geomorphic stability assessment involves 3 steps: (1) evaluating the site's past geomorphic stability by determining the age of the landscape and its associated deposits; (2) quantifying short- and long-term geomorphic processes operating in the site area; and (3) evaluating the

S. G. Wells; T. W. Gardner

1985-01-01

85

Identification of furin pro-region determinants involved in folding and activation.  

PubMed Central

The pro-region of the subtilisin-like convertase furin acts early in the biosynthetic pathway as an intramolecular chaperone to enable proper folding of the zymogen, and later on as an inhibitor to constrain the activity of the enzyme until it reaches the trans -Golgi network. To identify residues that are important for pro-region function, we initially identified amino acids that are conserved among the pro-regions of various mammalian convertases. Site-directed mutagenesis of 17 selected amino acids within the 89-residue pro-region and biosynthetic labelling revealed that I60A-furin and H66A-furin were rapidly degraded in a proteasome-dependent manner, while W34A-furin and F67A-furin did not show any autocatalytic activation. Intriguingly, the latter mutants proteolytically cleaved pro-von Willebrand factor precursor to the mature polypeptide, suggesting that the mutations permitted proper folding, but did not allow the pro-region to exercise its role in inhibiting the enzyme. Homology modelling of furin's pro-region revealed that residues Ile-60 and His-66 might be crucial in forming the binding interface with the catalytic domain, while residues Trp-34 and Phe-67 might be involved in maintaining a hydrophobic core within the pro-region itself. These results provide structural insights into the dual role of furin's pro-region. PMID:14741044

Bissonnette, Lyne; Charest, Gabriel; Longpré, Jean-Michel; Lavigne, Pierre; Leduc, Richard

2004-01-01

86

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. PMID:20066075

Hirokawa, Nobutaka; Tanaka, Yosuke; Okada, Yasushi

2009-01-01

87

Phi ({Phi}) and psi ({Psi}) angles involved in malarial peptide bonds determine sterile protective immunity  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer Phi ({Phi}) and psi ({Psi}) angles determine sterile protective immunity. Black-Right-Pointing-Pointer Modified peptide's tendency to assume a regular conformation related to a PPII{sub L}. Black-Right-Pointing-Pointer Structural modifications in mHABPs induce Ab and protective immunity. Black-Right-Pointing-Pointer mHABP backbone atom's interaction with HLA-DR{beta}1{sup Asterisk-Operator} is stabilised by H-bonds. -- Abstract: Modified HABP (mHABP) regions interacting with HLA-DR{beta}1{sup Asterisk-Operator} molecules have a more restricted conformation and/or sequence than other mHABPs which do not fit perfectly into their peptide binding regions (PBR) and do not induce an acceptable immune response due to the critical role of their {Phi} and {Psi} torsion angles. These angle's critical role was determined in such highly immunogenic, protection-inducing response against experimental malaria using the conformers (mHABPs) obtained by {sup 1}H-NMR and superimposed into HLA-DR{beta}1{sup Asterisk-Operator }-like Aotus monkey molecules; their phi ({Phi}) and psi ({Psi}) angles were measured and the H-bond formation between these molecules was evaluated. The aforementioned mHABP propensity to assume a regular conformation similar to a left-handed polyproline type II helix (PPII{sub L}) led to suggesting that favouring these conformations according to their amino acid sequence would lead to high antibody titre production and sterile protective immunity induction against malaria, thereby adding new principles or rules for vaccine development, malaria being one of them.

Patarroyo, Manuel E., E-mail: mepatarr@gmail.com [Fundacion Instituto de Inmunologia de Colombia (FIDIC), Bogota (Colombia); Universidad Nacional de Colombia, Bogota (Colombia); Moreno-Vranich, Armando; Bermudez, Adriana [Fundacion Instituto de Inmunologia de Colombia (FIDIC), Bogota (Colombia)] [Fundacion Instituto de Inmunologia de Colombia (FIDIC), Bogota (Colombia)

2012-12-07

88

Phi (?) and psi (?) angles involved in malarial peptide bonds determine sterile protective immunity.  

PubMed

Modified HABP (mHABP) regions interacting with HLA-DR?1(?) molecules have a more restricted conformation and/or sequence than other mHABPs which do not fit perfectly into their peptide binding regions (PBR) and do not induce an acceptable immune response due to the critical role of their ? and ? torsion angles. These angle's critical role was determined in such highly immunogenic, protection-inducing response against experimental malaria using the conformers (mHABPs) obtained by (1)H-NMR and superimposed into HLA-DR?1(?)-like Aotus monkey molecules; their phi (?) and psi (?) angles were measured and the H-bond formation between these molecules was evaluated. The aforementioned mHABP propensity to assume a regular conformation similar to a left-handed polyproline type II helix (PPII(L)) led to suggesting that favouring these conformations according to their amino acid sequence would lead to high antibody titre production and sterile protective immunity induction against malaria, thereby adding new principles or rules for vaccine development, malaria being one of them. PMID:23142598

Patarroyo, Manuel E; Moreno-Vranich, Armando; Bermúdez, Adriana

2012-12-01

89

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

90

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. PMID:21349835

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

2011-01-01

91

Myosin5a tail associates directly with Rab3A-containing compartments in neurons.  

PubMed

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. PMID:21349835

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

2011-04-22

92

Engineering assessment of inactive uranium mill tailings  

SciTech Connect

The Grand Junction site has been reevaluated in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Grand Junction, Colorado. 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 1.9 million tons of tailings at the Grand Junction site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The eight alternative actions presented herein range from millsite and off-site 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 $10,200,000 for stabilization in-place to about $39,500,000 for disposal in the DeBeque area, at a distance of about 35 mi, using transportation by rail. If transportation to DeBeque were by truck, the cost estimated to be about $41,900,000. Three principal alternatives for the reprocessing of the Grand Junction 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 $200/lb by heap leach and $150/lb by conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery appears not to be economically attractive.

Not Available

1981-07-01

93

Ecological aspects of microorganisms inhabiting uranium mill tailings  

USGS Publications Warehouse

Numbers and types of microorganisms in uranium mill tailings were determined using culturing techniques. Arthrobacter were found to be the predominant microorganism inhabiting the sandy tailings, whereas Bacillus and fungi predominated in the slime tailings. Sulfate-reducing bacteria, capable of leaching radium, were isolated in low numbers from tailings samples but were isolated in significantly high numbers from topsoil in contact with the tailings. The results are placed in the context of the magnitude of uranium mill tailings in the United States, the hazards posed by the tailings, and how such hazards could be enhanced or diminished by microbial activities. Patterns in the composition of the microbial population are evaluated with respect to the ecological variables that influence microbial growth. ?? 1987 Springer-Verlag New York Inc.

Miller, C.L.; Landa, E.R.; Updegraff, D.M.

1987-01-01

94

[Tail Plane Icing  

NASA Technical Reports Server (NTRS)

The Aviation Safety Program initiated by NASA in 1997 has put greater emphasis in safety related research activities. Ice-contaminated-tailplane stall (ICTS) has been identified by the NASA Lewis Icing Technology Branch as an important activity for aircraft safety related research. The ICTS phenomenon is characterized as a sudden, often uncontrollable aircraft nose- down pitching moment, which occurs due to increased angle-of-attack of the horizontal tailplane resulting in tailplane stall. Typically, this phenomenon occurs when lowering the flaps during final approach while operating in or recently departing from icing conditions. Ice formation on the tailplane leading edge can reduce tailplane angle-of-attack range and cause flow separation resulting in a significant reduction or complete loss of aircraft pitch control. In 1993, the Federal Aviation Authority (FAA) and NASA embarked upon a four-year research program to address the problem of tailplane stall and to quantify the effect of tailplane ice accretion on aircraft performance and handling characteristics. The goals of this program, which was completed in March 1998, were to collect aerodynamic data for an aircraft tail with and without ice contamination and to develop analytical methods for predicting the effects of tailplane ice contamination. Extensive dry air and icing tunnel tests which resulted in a database of the aerodynamic effects associated with tailplane ice contamination. Although the FAA/NASA tailplane icing program generated some answers regarding ice-contaminated-tailplane stall (ICTS) phenomena, NASA researchers have found many open questions that warrant further investigation into ICTS. In addition, several aircraft manufacturers have expressed interest in a second research program to expand the database to other tail configurations and to develop experimental and computational methodologies for evaluating the ICTS phenomenon. In 1998, the icing branch at NASA Lewis initiated a second multi-phase research program for tailplane icing (TIP II) to develop test methodologies and tailplane performance and handling qualities evaluation tools. The main objectives of this new NASA/Industry/Academia collaborative research programs were: (1) define and evaluate a sub-scale wind tunnel test methodology for determining tailplane performance degradation due to icing. (2) develop an experimental database of tailplane aerodynamic performance with and without ice contamination for a range of tailplane configurations. Wind tunnel tests were planned with representative general aviation aircraft, i.e., the Learjet 45, and a twin engine low speed aircraft. This report summarizes the research performed during the first year of the study, and outlines the work tasks for the second year.

1997-01-01

95

Determinants of male involvement in maternal and child health services in sub-Saharan Africa: a review  

PubMed Central

Introduction Male participation is a crucial component in the optimization of Maternal and Child Health (MCH) services. This is especially so where prevention strategies to decrease Mother-to-Child Transmission (MTCT) of Human Immunodeficiency Virus (HIV) are sought. This study aims to identify determinants of male partners’ involvement in MCH activities, focusing specifically on HIV prevention of maternal to child transmission (PMTCT) in sub-Saharan Africa. Methods Literature review was conducted using the following data bases: Pubmed/MEDLINE; CINAHL; EMBASE; COCHRANE; Psych INFORMATION and the websites of the International AIDS Society (IAS), the International AIDS Conference and the International Conference on AIDS in Africa (ICASA) 2011. Results We included 34 studies in this review, which reported on male participation in MCH and PMTCT services. The majority of studies defined male participation as male involvement solely during antenatal HIV testing. Other studies defined male involvement as any male participation in HIV couple counseling. We identified three main determinants for male participation in PMTCT services: 1) Socio-demographic factors such as level of education, income status; 2) health services related factors such as opening hours of services, behavior of health providers and the lack of space to accommodate male partners; and 3) Sociologic factors such as beliefs, attitudes and communication between men and women. Conclusion There are many challenges to increase male involvement/participation in PMTCT services. So far, few interventions addressing these challenges have been evaluated and reported. It is clear however that improvement of antenatal care services by making them more male friendly, and health education campaigns to change beliefs and attitudes of men are absolutely needed. PMID:23171709

2012-01-01

96

In helicopters the tail mainly serves to keep the aircraft  

E-print Network

In helicopters the tail mainly serves to keep the aircraft stable. The rotors are used to maneuver the helicopter. But a study at TU Delft revealed that involving the tail in commanding the helicopter not only reduces the structural load on the main rotor, but also makes the helicopter easier to handle

Langendoen, Koen

97

What Makes a Tidal Tail?  

NASA Astrophysics Data System (ADS)

Galaxy interactions are famous for creating some of the most visually stunning scenes in astronomy, particularly in the cases of tidal tails. These chaotic regions are known to house breeding grounds for young stellar clusters, as shown through past imaging and spectroscopic studies, but the underlying material remains a mystery. While we know that gas is easily stripped from the parent galaxies, what about the stars? The presence of an older stellar population is crucial to dynamical simulations of tidal tails, but has not yet been confirmed by observation. We use the twin tidal tails of NGC3256 as a case study for determining the presence of an old, underlying stellar population. Newly acquired ugriz Gemini data allows us to distinguish between young and old stars, while previous HST data pinpoints the locations of these objects. Deep imaging surveys have often been used to detect tidal features, including these ancient relics, but our survey will be the first to measure the colors of such objects. This will lead us to place constraints on the original composition of the material that was ejected from the interacting/merging galaxies, and the star formation history.

Rodruck, Michael; Konstantopoulos, I.; Charlton, J. C.

2014-01-01

98

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

99

Giant lens, a gene involved in cell determination and axon guidance in the visual system of Drosophila melanogaster.  

PubMed Central

Mutations in the Drosophila gene giant lens (gil) affect ommatidial development, photoreceptor axon guidance and optic lobe development. We have cloned the gene using an enhancer trap line. Molecular analysis of gil suggests that it encodes a secreted protein with an epidermal-growth-factor-like motif. We have generated mutations at the gil locus by imprecise excision of the enhancer trap P-element. In the absence of gil, additional photoreceptors develop at the expense of pigment cells, suggesting an involvement of gil in cell determination during eye development. In addition, gil mutants show drastic effects on photoreceptor axon guidance and optic lobe development. In wildtype flies, photoreceptor axons grow from the eye disc through the optic stalk into the larval brain hemisphere, where retinal innervation is required for the normal development of the lamina and distal medulla. The projection pattern of these axons in the developing lamina and medulla is highly regular and reproducible. In gil, photoreceptor axons enter the larval brain but fail to establish proper connections in the lamina or medulla. We propose that gil encodes a new type of signalling molecule involved in the process of axon pathfinding and cell determination in the visual system of Drosophila. Images PMID:1628618

Kretzschmar, D; Brunner, A; Wiersdorff, V; Pflugfelder, G O; Heisenberg, M; Schneuwly, S

1992-01-01

100

PssP2 Is a Polysaccharide Co-Polymerase Involved in Exopolysaccharide Chain-Length Determination in Rhizobium leguminosarum  

PubMed Central

Production of extracellular polysaccharides is a complex process engaging proteins localized in different subcellular compartments, yet communicating with each other or even directly interacting in multicomponent complexes. Proteins involved in polymerization and transport of exopolysaccharide (EPS) in Rhizobium leguminosarum are encoded within the chromosomal Pss-I cluster. However, genes implicated in polysaccharide synthesis are common in rhizobia, with several homologues of pss genes identified in other regions of the R. leguminosarum genome. One such region is chromosomally located Pss-II encoding proteins homologous to known components of the Wzx/Wzy-dependent polysaccharide synthesis and transport systems. The pssP2 gene encodes a protein similar to polysaccharide co-polymerases involved in determination of the length of polysaccharide chains in capsule and O-antigen biosynthesis. In this work, a mutant with a disrupted pssP2 gene was constructed and its capabilities to produce EPS and enter into a symbiotic relationship with clover were studied. The pssP2 mutant, while not altered in lipopolysaccharide (LPS), displayed changes in molecular mass distribution profile of EPS. Lack of the full-length PssP2 protein resulted in a reduction of high molecular weight EPS, yet polymerized to a longer length than in the RtTA1 wild type. The mutant strain was also more efficient in symbiotic performance. The functional interrelation between PssP2 and proteins encoded within the Pss-I region was further supported by data from bacterial two-hybrid assays providing evidence for PssP2 interactions with PssT polymerase, as well as glycosyltransferase PssC. A possible role for PssP2 in a complex involved in EPS chain-length determination is discussed. PMID:25268738

Marczak, Ma?gorzata; Matysiak, Paulina; Kutkowska, Jolanta; Skorupska, Anna

2014-01-01

101

Effects of aerodynamic interaction between main and tail rotors on helicopter hover performance and noise  

NASA Technical Reports Server (NTRS)

A model test was conducted to determine the effects of aerodynamic interaction between main rotor, tail rotor, and vertical fin on helicopter performance and noise in hover out of ground effect. The experimental data were obtained from hover tests performed with a .151 scale Model 222 main rotor, tail rotor and vertical fin. Of primary interest was the effect of location of the tail rotor with respect to the main rotor. Penalties on main rotor power due to interaction with the tail rotor ranged up to 3% depending upon tail rotor location and orientation. Penalties on tail rotor power due to fin blockage alone ranged up to 10% for pusher tail rotors and up to 50% for tractor tail rotors. The main rotor wake had only a second order effect on these tail rotor/fin interactions. Design charts are presented showing the penalties on main rotor power as a function of the relative location of the tail rotor.

Menger, R. P.; Wood, T. L.; Brieger, J. T.

1983-01-01

102

Use of CI-MS for the determination of deuterium content in hydrocarbons. ; Solutions for systems involving multiple ionization processes  

SciTech Connect

The application of chemical ionization mass spectrometry (CI-MS) to the analysis of hydrocarbons generally results in multiple ion reactions which produce analyte ions in the molecular ion region. Mathematical analysis of these processes for deuterium-containing species may be complex, but processes that involve mainly hydrogen addition or charge transfer may be modeled easily and the deuterium distribution in the analyte determined often without the complications of fragmentation or isotope effects. However, matrices that are used to model processes that result primarily from hydrogen abstraction with minor components of charge transfer and hydrogen addition have very large condition numbers, and direct solution is difficult and requires highly accurate spectra. The mathematics of these CI processes are also applicable to electron-impact (EI) spectra which produce fragmentation in the molecular ion region, and the mathematical ramifications on EI are discussed.

Price, G.L. (Dept of Chemical Engineering, Louisiana State Univ, Baton Rouge, LA (US)); Iglesia, E. (Corporate Research Labs, Exxon Research and Engineering Corp, NJ (US))

1989-11-01

103

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.

104

Endoplasmic reticulum quality control of asialoglycoprotein receptor H2a involves a determinant for retention and not?retrieval  

PubMed Central

The human asialoglycoprotein receptor H2a subunit contains a charged pentapeptide, EGHRG, in its ectodomain that is the only sequence absent from the H2b alternatively spliced variant. H2b exits the endoplasmic reticulum (ER) even when singly expressed, whereas H2a gives rise to a cleaved soluble secreted ectodomain fragment; uncleaved membrane-bound H2a molecules are completely retained and degraded in the ER. We have inserted the H2a pentapeptide into the sequence of the H1 subunit (H1i5), which caused complete ER retention but, unexpectedly, no degradation. This suggests that the pentapeptide is a determinant for ER retention not colocalizing in H2a with the determinant for degradation. The state of sugar chain processing and the ER localization of H1i5, which was unchanged at 15°C or after treatment with nocodazole, indicate ER retention and not retrieval from the cis-Golgi or the intermediate compartment. H1i5 folded similarly to H1, and both associated to calnexin. However, whereas H1 dissociated with a half time of 45 min, H1i5 remained bound to the chaperone for prolonged periods. The correct global folding of H2a and H1i5 and of other normal precursors and unassembled proteins and the true ER retention, and not exit and retrieval, suggest a difference in their quality control mechanism compared with that of misfolded proteins, which does involve retrieval. However, both pathways may involve calnexin. PMID:9326615

Shenkman, Marina; Ayalon, Michal; Lederkremer, Gerardo Z.

1997-01-01

105

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

106

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

107

Drop Tail (FIFO) FREDCBQ ......  

E-print Network

Drop Tail (FIFO) FREDCBQ ...... Class-Based Threshold (CBT) Dynamic-CBT Resource Reservation RED Active Queue Mgmt Dynamic-CBT ­ Better Performing Active Queue Management for Multimedia Networking Mark performance drop for multimedia flows that are well behaved. We extend Class-Based Threshold (CBT

Claypool, Mark

108

Drop Tail (FIFO) FREDCBQ ......  

E-print Network

Drop Tail (FIFO) FREDCBQ ...... Class-Based Threshold (CBT) Dynamic-CBT ChIPS Resource Reservation RED Active Queue Mgmt Dynamic-CBT and ChIPS ­ Router Support for Improved Multimedia Performance that use flow control. We extend Class- Based Threshold (CBT) [4], and propose a new active queue

Claypool, Mark

109

Drop Tail (FIFO) FREDCBQ ......  

E-print Network

Drop Tail (FIFO) FREDCBQ ...... Class-Based Threshold (CBT) Dynamic-CBT ChIPS Resource Reservation RED Active Queue Mgmt Dynamic-CBT and ChIPS ­ Router Support for Improved Multimedia Performance for multimedia flows that use flow control. We extend Class-Based Threshold (CBT) [12], and propose a new active

Claypool, Mark

110

Consistent with the spirit of the Americans with Disabilities Act, Illinois Institute of Technology determines reasonable accommodations through a deliberative process involving  

E-print Network

Grievances Consistent with the spirit of the Americans with Disabilities Act, Illinois Institute of Technology determines reasonable accommodations through a deliberative process involving disability services professionals, appropriate members of the university community, and, of course, individuals with disabilities

Heller, Barbara

111

Oxygen availability is a major factor in determining the composition of microbial communities involved in methane oxidation  

PubMed Central

We have previously observed that methane supplied to lake sediment microbial communities as a substrate not only causes a response by bona fide methanotrophic bacteria, but also by non-methane-oxidizing bacteria, especially by members of the family Methylophilaceae. This result suggested that methane oxidation in this environment likely involves communities composed of different functional guilds, rather than a single type of microbe. To obtain further support for this concept and to obtain further insights into the factors that may define such partnerships, we carried out microcosm incubations with sediment samples from Lake Washington at five different oxygen tensions, while methane was supplied at the same concentration in each. Community composition was determined through 16S rRNA gene amplicon sequencing after 10 and 16 weeks of incubation. We demonstrate that, in support of our prior observations, the methane-consuming communities were represented by two major types: the methanotrophs of the family Methylococcaceae and by non-methanotrophic methylotrophs of the family Methylophilaceae. However, different species persisted under different oxygen tensions. At high initial oxygen tensions (150 to 225 µM) the major players were, respectively, species of the genera Methylosarcina and Methylophilus, while at low initial oxygen tensions (15 to 75 µM) the major players were Methylobacter and Methylotenera. These data suggest that oxygen availability is at least one major factor determining specific partnerships in methane oxidation. The data also suggest that speciation within Methylococcaceae and Methylophilaceae may be driven by niche adaptation tailored toward specific placements within the oxygen gradient. PMID:25755930

Hernandez, Maria E.; Beck, David A.C.; Lidstrom, Mary E.

2015-01-01

112

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. PMID:22793670

2012-01-01

113

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

114

Economic evaluation of inactive uranium mill tailings, Gunnison Site, Gunnison, 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)] [Mountain States Research and Development, Tucson, AZ (United States)

1982-12-01

115

Western Red-tailed Skink Distribution in Southern Nevada  

SciTech Connect

This slide show reports a study to: determine Western Red-tailed Skink (WRTS) distribution on Nevada National Security Site (NNSS); identify habitat where WRTS occur; learn more about WRTS natural history; and document distribution of other species.

Hall, D. B. and Gergor, P. D.

2011-11-01

116

The plasma tail of comet Bennett 1970 II  

Microsoft Academic Search

A set of fourteen large-scale exposures of comet Bennett 1970 II between 1970 April 27 and 30 are evaluated. The solar wind velocity is determined for this period from the aberration angle of the plasma tail.

J. Zvolánková; D. Kubácek; E. M. Pittich

1987-01-01

117

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

2009-01-01

118

Modeling the neutral sodium tails of comets  

NASA Astrophysics Data System (ADS)

Neutral sodium is typically easy to detect in active comets around perihelion, due to the very high efficiency of the sodium D transition, and, at some comets, a distinct neutral sodium tail is observed. The first distinct neutral sodium tail images were apparent in C/1995 O1 (Hale-Bopp) data taken using CoCam [1], but, since this initial detection, similar features have been observed at near-Sun comets using the LASCO coronagraph on SOHO. A full picture of the distribution and evolution of neutral cometary sodium may best be established using a combination of spectra and images in different filters at multiple times throughout the orbit. The high efficiency of the sodium D transition has allowed it to be detected in systems, even if the column density of sodium is extremely low. In these instances it is sometimes possible to determine some of the system's characteristics from the sodium emission detection, such as in Io's plasma torus [2] and Enceladus's plume [3,4]. It is hoped that a similar approach may be applied to the active cometary environment, but, at present, the production of neutral sodium is unknown. Various authors [5--9, thorough review presented in 10] have suggested various combinations of sources of neutral sodium in the nuclear region, near-nuclear region, dust tail, and ion tail. The morphology and evolution of the neutral cometary sodium tail are difficult to intuitively predict due to the Swings and Greenstein effects. In order to understand the wide variety of cometary observations of neutral sodium available we have developed the first fully three-dimensional, heliocentric-distance-dependent, versatile Monte Carlo neutral sodium tail model, which incorporates the unintuitive variation in radiation pressure influences on sodium atoms with different heliocentric velocities. Our model was initially based on that of Brown et al [7]. We present preliminary results from this model. We have found initial agreement with the overall morphology and brightness of the neutral sodium tail observed at C/1995 O1 (Hale-Bopp, for which this phenomenon was studied most extensively) and our model, and have begun to extend the study to other comets of interest. We also present our initial analysis of the likely presence of neutral sodium in the SOHO LASCO images of C/2012 S1 (ISON) and a comparison of this dataset with our model. The versatility of the model allows it to be easily adapted to any other cometary sodium tail.

Birkett, K.; Jones, G.; Coates, A.

2014-07-01

119

Heads and Tails  

E-print Network

novellas by Sebastian, Helen Raven, & M. Fae Glasgow) WARNING: THIS ANTHOLOGY CONTAINS SAME-SEX, ADULT-ORIENTED MATERIAL. IT WILL NOT BE SOLD TO ANYONE UNDER THE AGE OF EIGHTEEN. Bene Dictum IV: Heads & Tails an anthology of X-Files slash fiction... exclusively. There are, however, two pieces bringing Krycek into the picture: ?Trinity? and ?Torrid.? As usual, M. Fae writes her own particular view of the Sk/M relation- ship and her stories range from romantic to hopeless; from no sex shown at all...

Glasgow, M.F.

1999-01-01

120

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

121

Experiments on a Tail-wheel Shimmy  

NASA Technical Reports Server (NTRS)

Model tests on the "running belt" and tests with a full-scale tail wheel were made on a rotating drum as well as on a runway in order to investigate the causes of the undesirable shimmy phenomena frequently occurring on airplane tail wheels, and the means of avoiding them. The small model (scale 1:10) permitted simulation of the mass, moments of inertia, and fuselage stiffness of the airplane and determination of their influence on the shimmy, whereas by means of the larger model with pneumatic tires (scale 1:2) more accurate investigations were made on the tail wheel itself. The results of drum and road tests show good agreement with one another and with model values. Detailed investigations were made regarding the dependence of the shimmy tendency on trail, rolling speed, load, size of tires, ground friction,and inclination of the swivel axis; furthermore, regarding the influence of devices with restoring effect on the tail wheel, and the friction damping required for prevention of shimmy. Finally observations from slow-motion pictures are reported and conclusions drawn concerning the influence of tire deformation.

Harling, R; Dietz, O

1954-01-01

122

The ionospheres and plasma tails of comets  

Microsoft Academic Search

The paper reviews the current state of knowledge about cometary plasma (type I) tails and ionospheres. Observational statistics for type I tails are examined along with spectroscopic observations of plasma tails, identified ion species in such tails, and the morphology of cometary plasma tails and ionospheres. Evidence for a strong interaction between comets and the solar wind is evaluated on

D. A. Mendis; W.-H. Ip

1977-01-01

123

Tail contribution to the directional aerodynamic characteristics of a 1/6-scale model of the rotor systems research aircraft with a tail rotor  

NASA Technical Reports Server (NTRS)

The results are presented of a wind tunnel investigation to determine the tail contribution to the directional aerodynamic characteristics of a 1/6-scale model of the rotor systems research aircraft (RSRA) with a tail rotor. No main rotor was used during the investigation. Data were obtained with and without the tail rotor over a range of sideslip angle and over a range of rotor collective pitch angle. The model with the tail rotor was tested at several advance ratios with and without thrust from the auxiliary thrust engines on the RSRA fuselage. Increasing the space between the tail-rotor hub and the vertical tail reduced the tail-rotor torque required at moderate to high rotor thrust. Increasing the exit dynamic pressure of the auxiliary thrust engines decreases the tail contribution to the static directional stability. The tail-rotor thrust and its interference provide a positive increment to the static directional stability. The tail contribution increases with forward speed. The adverse yawing moment of the airframe would strongly affect the thrust required of the tail rotor when the helicopter is hovering in a crosswind.

Mineck, R. E.

1977-01-01

124

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

125

Elucidating Internucleosome Interactions and the Roles of Histone Tails  

PubMed Central

The nucleosome is the first level of genome organization and regulation in eukaryotes where negatively charged DNA is wrapped around largely positively charged histone proteins. Interaction between nucleosomes is dominated by electrostatics at long range and guided by specific contacts at short range, particularly involving their flexible histone tails. We have thus quantified how internucleosome interactions are modulated by salts (KCl, MgCl2) and histone tail deletions (H3, H4 N-terminal), using small-angle x-ray scattering and theoretical modeling. We found that measured effective charges at low salts are ?1/5th of the theoretically predicted renormalized charges and that H4 tail deletion suppresses the attraction at high salts to a larger extent than H3 tail deletion. PMID:23823239

Howell, Steven C.; Andresen, Kurt; Jimenez-Useche, Isabel; Yuan, Chongli; Qiu, Xiangyun

2013-01-01

126

School commitment, student perception of school efforts to involve students in the education process, self determination and behavioral and educational outcomes  

Microsoft Academic Search

The relationships among school commitment, student perceptions of school efforts to facilitate student involvement, and self determination and behavioral and educational outcomes were examined. The behavioral outcomes model analyzed the relationships among school commitment in early high school and substance use and school delinquency in early high school, as well as substance use in later high school. It was hypothesized

Wendy Morrison Cavendish

2006-01-01

127

NPS6, Encoding a Non-Ribosomal Peptide Synthetase Involved in Siderophore-Mediated Iron Metabolism, is a Conserved Virulence Determinant of Plant Pathogenic Ascomycetes  

Technology Transfer Automated Retrieval System (TEKTRAN)

NPS6, encoding a non-ribosomal peptide synthetase, is a virulence determinant in the corn pathogen Cochliobolus heterostrophus and is also involved in resistance to oxidative stress, generated by hydrogen peroxide. Deletion of NPS6 orthologs in the rice pathogen, Cochliobolus miyabeanus, the cereal...

128

From dinosaurs to birds: a tail of evolution  

PubMed Central

A particularly critical event in avian evolution was the transition from long- to short-tailed birds. Primitive bird tails underwent significant alteration, most notably reduction of the number of caudal vertebrae and fusion of the distal caudal vertebrae into an ossified pygostyle. These changes, among others, occurred over a very short evolutionary interval, which brings into focus the underlying mechanisms behind those changes. Despite the wealth of studies delving into avian evolution, virtually nothing is understood about the genetic and developmental events responsible for the emergence of short, fused tails. In this review, we summarize the current understanding of the signaling pathways and morphological events that contribute to tail extension and termination and examine how mutations affecting the genes that control these pathways might influence the evolution of the avian tail. To generate a list of candidate genes that may have been modulated in the transition to short-tailed birds, we analyzed a comprehensive set of mouse mutants. Interestingly, a prevalent pleiotropic effect of mutations that cause fused caudal vertebral bodies (as in the pygostyles of birds) is tail truncation. We identified 23 mutations in this class, and these were primarily restricted to genes involved in axial extension. At least half of the mutations that cause short, fused tails lie in the Notch/Wnt pathway of somite boundary formation or differentiation, leading to changes in somite number or size. Several of the mutations also cause additional bone fusions in the trunk skeleton, reminiscent of those observed in primitive and modern birds. All of our findings were correlated to the fossil record. An open question is whether the relatively sudden appearance of short-tailed birds in the fossil record could be accounted for, at least in part, by the pleiotropic effects generated by a relatively small number of mutational events. PMID:25621146

2014-01-01

129

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

130

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. PMID:9445022

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

1998-01-01

131

The Pressure Distribution Over the Horizontal Tail Surfaces of an Airplane I  

NASA Technical Reports Server (NTRS)

This work was undertaken to determine as completely as possible the distribution of pressure over the horizontal tail surfaces of an airplane, and to analyze the relation of this pressure to the structural loads and the longitudinal stability. The investigation is divided into three parts, of which this the first. The first part of the investigation is for the purpose of determining the pressure distribution over two horizontal tail surfaces in uniform free flight; the second part to conduct tests of similar tail planes in the wind tunnel; and the third part to determine the pressure distribution on the horizontal tail surfaces during accelerated flight on the full-size airplane.

Norton, F H

1923-01-01

132

Cooling Characteristics of an Experimental Tail-pipe Burner with an Annular Cooling-air Passage  

NASA Technical Reports Server (NTRS)

The effects of tail-pipe fuel-air ratio (exhaust-gas temperatures from approximately 3060 degrees to 3825 degrees R), radial distributiion of tail-pipe fuel flow, and mass flow of combustion gas and the inside wall were determined for an experimental tail-pipe burner cooled by air flowing through and insulated cooling-air to combustion gas mass flow from 0.066 to 0.192 were also determined.

Kaufman, Harold R; Koffel, William K

1952-01-01

133

The Pressure Distribution over the Wings and Tail Surfaces of a PW-9 Pursuit Airplane in Flight  

NASA Technical Reports Server (NTRS)

This report presents the results of an investigation to determine (1) the magnitude and distribution of aerodynamic loads over the wings and tail surfaces of a pursuit-type airplane in the maneuvers likely to impose critical loads on the various subassemblies of the airplane structure. (2) To study the phenomenon of center of pressure movement and normal force coefficient variation in accelerated flight, and (3) to measure the normal accelerations at the center of gravity, wing-tip, and tail, in order to determine the nature of the inertia forces acting simultaneously with the critical aerodynamic loads. The results obtained throw light on a number of important questions involving structural design. Some of the more interesting results are discussed in some detail, but in general the report is for the purpose of making this collection of airplane-load data obtained in flight available to those interested in airplane structures.

Rhode, Richard

1931-01-01

134

A Study to Determine Whether There Is an Improvement in Attitude in Students Involved in Cooperative Education Programs.  

ERIC Educational Resources Information Center

A study was conducted at Herkimer County Community College to determine whether a 40-hour work study experience affected the work attitudes of secretarial science students. The study population consisted of a group of June 1984 secretarial science degree candidates who had not yet participated in the work study program, and a group of 1982 and…

Testa, Donna M.

135

Formation and composition of cemented layers in low-sulphide mine tailings, Laver, northern Sweden  

NASA Astrophysics Data System (ADS)

Cemented layers (hardpans) are common in carbonate or sulphide-rich mine tailings and where pyrrhotite is the predominating Fe-sulphide. Laver, northern Sweden, is an abandoned Cu-mine where the tailings have low pyrrhotite content, almost no pyrite and no carbonates. Two cemented layers at different locations in the Laver tailings impoundment were investigated, with the aim to determine their effects on metal mobility. The cementing agents were mainly jarosite and Fe-oxyhydroxides in the layer formed where the tailings have a barren surface, whereas only Fe-oxyhydroxides were identified below grass-covered tailings surface. Arsenic was enriched in both layers which also exhibit high concentrations of Mo, V, Hg and Pb compared to unoxidised tailings. Sequential extraction indicates that these metals and As were mainly retained with crystalline Fe-oxides, and therefore potentially will be remobilised if the oxic conditions become more reducing, for instance as a result of remediation of the tailings impoundment.

Alakangas, Lena; Öhlander, Björn

2006-08-01

136

Theory of band tails in heavily doped semiconductors  

NASA Astrophysics Data System (ADS)

The random distribution of impurities in a semiconductor host lattice introduces potential fluctuations that allow energy levels within the forbidden energy gap. This statistical effect distorts the unperturbed density of states of the pure semiconductor, and, at high doping concentrations, substantial band tails appear. The changes in the density-of-states function are particularly important in determining the number of free carriers in a heavily doped semiconductor. Together with many-particle interactions, band tailing constitutes one of the most significant heavy-doping effects. Although the band-tailing phenomenon has been studied for many years, only a one-dimensional analytical model, which assumes a Gaussian whitenoise probability distribution of the potential fluctuation, exists. In this paper the different classes of theories that describe this band tailing of the density of states in heavily doped semiconductors are reviewed in detail.

van Mieghem, Piet

1992-07-01

137

HIV-1 Nef responsiveness is determined by Env variable regions involved in trimer association and correlates with neutralization sensitivity.  

PubMed

HIV-1 Nef and the unrelated murine leukemia virus glycoGag similarly enhance the infectivity of HIV-1 virions. We now show that the effects of Nef and glycoGag are similarly determined by variable regions of HIV-1 gp120 that control Env trimer association and neutralization sensitivity. Whereas neutralization-sensitive X4-tropic Env proteins conferred high responsiveness to Nef and glycoGag, particles bearing neutralization-resistant R5-tropic Envs were considerably less affected. The profoundly different Nef/glycoGag responsiveness of a neutralization-resistant and a neutralization-sensitive R5-tropic Env could be switched by exchanging their gp120 V1/V2 regions, which also switches their neutralization sensitivity. Within V1/V2, the same determinants governed Nef/glycoGag responsiveness and neutralization sensitivity, indicating that these phenotypes are mechanistically linked. The V1/V2 and V3 regions, which form an apical trimer-association domain, together determined the Nef and glycoGag responsiveness of an X4-tropic Env. Our results suggest that Nef and glycoGag counteract the inactivation of Env spikes with relatively unstable apical trimer-association domains. PMID:24209751

Usami, Yoshiko; Göttlinger, Heinrich

2013-11-14

138

Sex Differences in the Right Tail of Cognitive Abilities: A 30 Year Examination  

ERIC Educational Resources Information Center

One factor in the debate surrounding the underrepresentation of women in science technology, engineering and mathematics (STEM) involves male-female mathematical ability differences in the extreme right tail (top 1% in ability). The present study provides male-female ability ratios from over 1.6 million 7th grade students in the right tail (top 5%…

Wai, Jonathan; Cacchio, Megan; Putallaz, Martha; Makel, Matthew C.

2010-01-01

139

Indicators of Microbial Sulfate Reduction in Acidic Sulfide-Rich Mine Tailings  

Microsoft Academic Search

Sulfate-reducing bacteria (SRB) are thought to be actively involved in the cycling of sulfur in acidic mine tailings. However, most studies have used circumstantial evidence to assess microbial sulfate activity in such environments. In order to fully ascertain the role of sulfate-reducing bacteria (SRB) in sulfur cycling in acidic mine tailings, we measured sulfate reduction rates, sulfur isotopic composition of

Tanmay Praharaj; Danielle Fortin

2004-01-01

140

Draft Genome Sequences of Campylobacterales (Epsilonproteobacteria) Obtained from Methanogenic Oil Sands Tailings Pond Metagenomes  

PubMed Central

Draft genome sequences of two Campylobacterales (Sulfurospirillum sp. strain SCADC and Sulfuricurvum sp. strain MLSB [Mildred Lake Settling Basin]) were obtained by taxonomic binning of metagenomes originating from an oil sands tailings pond. Both genomes contain soxABXYZ genes involved in sulfur oxidation, highlighting their potential roles in sulfur cycling in oil sands tailings ponds. PMID:25323712

Tan, BoonFei

2014-01-01

141

Experimental study of main rotor tip geometry and tail rotor interactions in hover. Volume 1. Text and figures  

NASA Technical Reports Server (NTRS)

A model scale hover test was conducted in the Sikorsky Aircraft Model rotor hover Facility to identify and quantify the impact of the tail rotor on the demonstrated advantages of advanced geometry tip configurations. The test was conducted using the Basic Model Test Rig and two scaled main rotor systems, one representing a 1/5.727 scale UH-60A BLACK HAWK and the others a 1/4.71 scale S-76. Eight alternate rotor tip configurations were tested, 3 on the BLACK HAWK rotor and 6 on the S-76 rotor. Four of these tips were then selected for testing in close proximity to an operating tail rotor (operating in both tractor and pusher modes) to determine if the performance advantages that could be obtained from the use of advanced geometry tips in a main rotor only environment would still exist in the more complex flow field involving a tail rotor. The test showed that overall the tail rotor effects on the advanced tip configurations tested are not substantially different from the effects on conventional tips.

Balch, D. T.; Lombardi, J.

1985-01-01

142

Experimental study of main rotor tip geometry and tail rotor interactions in hover. Volume 2: Run log and tabulated data  

NASA Technical Reports Server (NTRS)

A model scale hover test was conducted in the Sikorsky Aircraft Model Rotor hover Facility to identify and quantify the impact of the tail rotor on the demonstrated advantages of advanced geometry tip configurations. The existence of mutual interference between hovering main rotor and a tail rotor was acknowledged in the test. The test was conducted using the Basic Model Test Rig and two scaled main rotor systems, one representing a 1/5.727 scale UH-60A BLACK HAWK and the others a 1/4.71 scale S-76. Eight alternate rotor tip configurations were tested, 3 on the BLACK HAWK rotor and 6 on the S-76 rotor. Four of these tips were then selected for testing in close proximity to an operating tail rotor (operating in both tractor and pusher modes) to determine if the performance advantages that could be obtained from the use of advanced geometry tips in a main rotor only environment would still exist in the more complex flow field involving a tail rotor. This volume contains the test run log and tabulated data.

Balch, D. T.; Lombardi, J.

1985-01-01

143

Catalytic Analysis of APOBEC3G Involving Real-Time NMR Spectroscopy Reveals Nucleic Acid Determinants for Deamination  

PubMed Central

APOBEC3G (A3G) is a single-stranded DNA-specific cytidine deaminase that preferentially converts cytidine to uridine at the third position of triplet cytosine (CCC) hotspots. A3G restricts the infectivity of viruses, such as HIV-1, by targeting CCC hotspots scattered through minus DNA strands, reverse-transcribed from genomic RNA. Previously, we developed a real-time NMR method and elucidated the origin of the 3'?5' polarity of deamination of DNA by the C-terminal domain of A3G (CD2), which is a phenomenon by which a hotspot located closer to the 5'-end is deaminated more effectively than one less close to the 5'-end, through quantitative analysis involving nonspecific binding to and sliding along DNA. In the present study we applied the real-time NMR method to analyze the catalytic activity of CD2 toward DNA oligonucleotides containing a nucleotide analog at a single or multiple positions. Analyses revealed the importance of the sugar and base moieties throughout the consecutive 5 nucleotides, the CCC hotspot being positioned at the center. It was also shown that the sugar or base moieties of the nucleotides outside this 5 nucleotide recognition sequence are also relevant as to CD2's activity. Analyses involving DNA oligonucleotides having two CCC hotspots linked by a long sequence of either deoxyribonucleotides, ribonucleotides or abasic deoxyribonucleotides suggested that the phosphate backbone is required for CD2 to slide along the DNA strand and to exert the 3'?5' polarity. Examination of the effects of different salt concentrations on the 3'?5' polarity indicated that the higher the salt concentration, the less prominent the 3'?5' polarity. This is most likely the result of alleviation of sliding due to a decrease in the affinity of CD2 with the phosphate backbone at high salt concentrations. We also investigated the reactivity of substrates containing 5-methylcytidine (5mC) or 5-hydroxymethylcytidine, and found that A3G exhibited low activity toward 5mC. PMID:25875164

Kamba, Keisuke; Nagata, Takashi; Katahira, Masato

2015-01-01

144

Cleavage by signal peptide peptidase is required for the degradation of selected tail-anchored proteins  

PubMed Central

The regulated turnover of endoplasmic reticulum (ER)–resident membrane proteins requires their extraction from the membrane lipid bilayer and subsequent proteasome-mediated degradation. Cleavage within the transmembrane domain provides an attractive mechanism to facilitate protein dislocation but has never been shown for endogenous substrates. To determine whether intramembrane proteolysis, specifically cleavage by the intramembrane-cleaving aspartyl protease signal peptide peptidase (SPP), is involved in this pathway, we generated an SPP-specific somatic cell knockout. In a stable isotope labeling by amino acids in cell culture–based proteomics screen, we identified HO-1 (heme oxygenase-1), the rate-limiting enzyme in the degradation of heme to biliverdin, as a novel SPP substrate. Intramembrane cleavage by catalytically active SPP provided the primary proteolytic step required for the extraction and subsequent proteasome-dependent degradation of HO-1, an ER-resident tail-anchored protein. SPP-mediated proteolysis was not limited to HO-1 but was required for the dislocation and degradation of additional tail-anchored ER-resident proteins. Our study identifies tail-anchored proteins as novel SPP substrates and a specific requirement for SPP-mediated intramembrane cleavage in protein turnover. PMID:24958774

Boname, Jessica M.; Bloor, Stuart; Wandel, Michal P.; Nathan, James A.; Antrobus, Robin; Dingwell, Kevin S.; Thurston, Teresa L.; Smith, Duncan L.; Smith, James C.; Randow, Felix

2014-01-01

145

Theseus Tail Being Unloaded  

NASA Technical Reports Server (NTRS)

The tail of the Theseus prototype research aircraft is seen here being unloaded at NASA's Dryden Flight Research Center, Edwards, California, in May of 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

1996-01-01

146

Development of a biologically inspired hydrobot tail  

NASA Astrophysics Data System (ADS)

It has been hypothesized that Europa, one of the moons of Jupiter, has a large ocean underneath a thick layer of ice. In order to determine whether life exists, it has been proposed that an underwater glider (hydrobot) capable of propulsion could be sent to explore the vast ocean. In this research, we considered various smart materials to create a propulsion device inspired by dolphin tails. Dolphins are highly efficient and excellent gliders, which makes them the ideal candidate for ocean exploration. In order to select the best dolphin species, we began by reviewing literature and then utilized the Analytical Hierarchy Process (AHP) to compare the different species. Lagenorhynchus obliquidens (Pacific White-Sided Dolphin) was found to be the best choice for creating a bioinspired hydrobot. We then conducted literature review of various smart materials and using this knowledge constructed a hydrobot tail prototype. This prototype demonstrates that smart materials can be fashioned into suitable actuators to control a tail fashioned after a dolphin.

Moore, Danielle; Janneh, Alhaji; Philen, Michael

2014-04-01

147

Managing forests for white-tailed eagles  

E-print Network

Managing forests for white-tailed eagles White-tailed eagles (sea eagles) were re and carry out forestry operations and other activities in relation to the statutory protection of white-tailed eagles (sea eagles). It replaces general guidance relating to white-tailed eagles contained in Forestry

148

Note on late-time tails of spherical nonlinear waves  

SciTech Connect

We consider the longtime behavior of small amplitude solutions of the semilinear wave equation ()squarelg(){phi}={phi}{sup p} in odd d{>=}5 spatial dimensions. We show that for the quadratic nonlinearity (p=2) the tail has an anomalously small amplitude and fast decay. The extension of the results to more general nonlinearities involving first derivatives is also discussed.

Bizon, Piotr; Rostworowski, Andrzej [M. Smoluchowski Institute of Physics, Jagiellonian University, Krakow (Poland); Chmaj, Tadeusz [H. Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Krakow (Poland); Cracow University of Technology, Krakow (Poland)

2008-07-15

149

Determinants involved in subtype-specific functions of rat trace amine-associated receptors 1 and 4  

PubMed Central

Aims The trace amine-associated receptor (Taar) family displays high species- and subtype-specific pharmacology. Several trace amines such as ?-phenylethylamine (?-PEA), p-tyramine and tryptamine are agonists at TA1 but poorly activate rat and mouse Taar4. Principal Results Using rat TA1 and Taar4 chimera, we identified determinants in transmembrane helices 3 and 6, which, when replaced by the corresponding portion of rat TA1, can rescue cell surface expression of rat Taar4. When expressed at the cell surface, rat Taar4 pharmacology was very similar to that of TA1 and coupled to the G?s-protein/AC pathway. Our data suggest that binding pockets of Taar for surrogate agonists overlap between paralogs. Conclusions This implicates that the repertoire of Taar ensures functional redundancy, tissue- and cell-specific expression and/or different downstream signalling rather than different agonist specificity. PMID:23072560

Stäubert, C; Bohnekamp, J; Schöneberg, T

2013-01-01

150

The Principal Genetic Determinants for Nasopharyngeal Carcinoma in China Involve the HLA Class I Antigen Recognition Groove  

PubMed Central

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy facilitated by Epstein-Barr Virus infection. Here we resolve the major genetic influences for NPC incidence using a genome-wide association study (GWAS), independent cohort replication, and high-resolution molecular HLA class I gene typing including 4,055 study participants from the Guangxi Zhuang Autonomous Region and Guangdong province of southern China. We detect and replicate strong association signals involving SNPs, HLA alleles, and amino acid (aa) variants across the major histocompatibility complex-HLA-A, HLA –B, and HLA -C class I genes (PHLA-A-aa-site-62?=?7.4×10?29; P HLA-B-aa-site-116?=?6.5×10?19; P HLA-C-aa-site-156?=?6.8×10?8 respectively). Over 250 NPC-HLA associated variants within HLA were analyzed in concert to resolve separate and largely independent HLA-A, -B, and -C gene influences. Multivariate logistical regression analysis collapsed significant associations in adjacent genes spanning 500 kb (OR2H1, GABBR1, HLA-F, and HCG9) as proxies for peptide binding motifs carried by HLA- A*11:01. A similar analysis resolved an independent association signal driven by HLA-B*13:01, B*38:02, and B*55:02 alleles together. NPC resistance alleles carrying the strongly associated amino acid variants implicate specific class I peptide recognition motifs in HLA-A and -B peptide binding groove as conferring strong genetic influence on the development of NPC in China. PMID:23209447

Tang, Minzhong; Lautenberger, James A.; Gao, Xiaojiang; Sezgin, Efe; Hendrickson, Sher L.; Troyer, Jennifer L.; David, Victor A.; Guan, Li; Mcintosh, Carl E.; Guo, Xiuchan; Zheng, Yuming; Liao, Jian; Deng, Hong; Malasky, Michael; Kessing, Bailey; Winkler, Cheryl A.; Carrington, Mary; dé The, Guy; Zeng, Yi; O'Brien, Stephen J.

2012-01-01

151

SASP, a Senescence-Associated Subtilisin Protease, is involved in reproductive development and determination of silique number in Arabidopsis.  

PubMed

Senescence involves increased expression of proteases, which may participate in nitrogen recycling or cellular signalling. 2D zymograms detected two protein species with increased proteolytic activity in senescing leaves of Arabidopsis thaliana. A proteomic analysis revealed that both protein species correspond to a subtilisin protease encoded by At3g14067, termed Senescence-Associated Subtilisin Protease (SASP). SASP mRNA levels and enzyme activity increase during leaf senescence in leaves senescing during both the vegetative or the reproductive phase of the plant life cycle, but this increase is more pronounced in reproductive plants. SASP is expressed in all above-ground organs, but not in roots. Putative AtSASP orthologues were identified in dicot and monocot crop species. A phylogenetic analysis shows AtSASP and its putative orthologues clustering in one discrete group of subtilisin proteases in which no other Arabidospsis subtilisin protease is present. Phenotypic analysis of two knockout lines for SASP showed that mutant plants develop more inflorescence branches during reproductive development. Both AtSASP and its putative rice orthologue (OsSASP) were constitutively expressed in sasp-1 to complement the mutant phenotype. At maturity, sasp-1 plants produced 25% more inflorescence branches and siliques than either the wild-type or the rescued lines. These differences were mostly due to an increased number of second and third order branches. The increased number of siliques was compensated for by a small decrease (5.0%) in seed size. SASP downregulates branching and silique production during monocarpic senescence, and its function is at least partially conserved between Arabidopsis and rice. PMID:25371504

Martinez, Dana E; Borniego, Maria L; Battchikova, Natalia; Aro, Eva-Mari; Tyystjärvi, Esa; Guiamét, Juan J

2015-01-01

152

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. PMID:19740891

Higham, Timothy E.; Russell, Anthony P.

2010-01-01

153

Volatile Compounds in Honey: A Review on Their Involvement in Aroma, Botanical Origin Determination and Potential Biomedical Activities  

PubMed Central

Volatile organic compounds (VOCs) in honey are obtained from diverse biosynthetic pathways and extracted by using various methods associated with varying degrees of selectivity and effectiveness. These compounds are grouped into chemical categories such as aldehyde, ketone, acid, alcohol, hydrocarbon, norisoprenoids, terpenes and benzene compounds and their derivatives, furan and pyran derivatives. They represent a fingerprint of a specific honey and therefore could be used to differentiate between monofloral honeys from different floral sources, thus providing valuable information concerning the honey’s botanical and geographical origin. However, only plant derived compounds and their metabolites (terpenes, norisoprenoids and benzene compounds and their derivatives) must be employed to discriminate among floral origins of honey. Notwithstanding, many authors have reported different floral markers for honey of the same floral origin, consequently sensory analysis, in conjunction with analysis of VOCs could help to clear this ambiguity. Furthermore, VOCs influence honey’s aroma described as sweet, citrus, floral, almond, rancid, etc. Clearly, the contribution of a volatile compound to honey aroma is determined by its odor activity value. Elucidation of the aroma compounds along with floral origins of a particular honey can help to standardize its quality and avoid fraudulent labeling of the product. Although only present in low concentrations, VOCS could contribute to biomedical activities of honey, especially the antioxidant effect due to their natural radical scavenging potential. PMID:22272147

Manyi-Loh, Christy E.; Ndip, Roland N.; Clarke, Anna M.

2011-01-01

154

[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

155

Does climate have heavy tails?  

NASA Astrophysics Data System (ADS)

When we speak about a distribution with heavy tails, we are referring to the probability of the existence of extreme values will be relatively large. Several heavy-tail models are constructed from Poisson processes, which are the most tractable models. Among such processes, one of the most important are the Lévy processes, which are those process with independent, stationary increments and stochastic continuity. If the random component of a climate process that generates the data exhibits a heavy-tail distribution, and if that fact is ignored by assuming a finite-variance distribution, then there would be serious consequences (in the form, e.g., of bias) for the analysis of extreme values. Yet, it appears that it is an open question to what extent and degree climate data exhibit heavy-tail phenomena. We present a study about the statistical inference in the presence of heavy-tail distribution. In particular, we explore (1) the estimation of tail index of the marginal distribution using several estimation techniques (e.g., Hill estimator, Pickands estimator) and (2) the power of hypothesis tests. The performance of the different methods are compared using artificial time-series by means of Monte Carlo experiments. We systematically apply the heavy tail inference to observed climate data, in particular we focus on time series data. We study several proxy and directly observed climate variables from the instrumental period, the Holocene and the Pleistocene. This work receives financial support from the European Commission (Marie Curie Initial Training Network LINC, No. 289447, within the 7th Framework Programme).

Bermejo, Miguel; Mudelsee, Manfred

2013-04-01

156

Long-term stabilization of uranium mill tailings  

SciTech Connect

The primary hazard associated with uranium mill tailings is exposure to a radioactive gas, radon-222, the concentration of which has been correlated with the occurrence of lung cancer. Previous studies on radon attenuation conclude that the placement of earthen cover materials over the tailings is the most effective technique for reducing radioactive emissions and dispersal of tailings. The success of such a plan, however, is dependent on ensuring the long-term integrity of these cover materials. Soil erosion from water and wind is the major natural cause of destabilizing earthen cover materials. Field data related to the control of soil loss are limited and only indirectly apply to the problem of isolation of uranium mill tailings over very long time periods (up to 80,000 a). However, sufficient information is available to determine benefits that will result from the changes in specific design variables and to evaluate the need for different design strategies among potential disposal sites. The three major options available for stabilization of uranium mill tailings are: rock cover, soil and revegetation, or a combination of both on different portions of the tailings cover. The optimal choice among these alternatives depends on site-specific characteristics such as climate and local geomorphology and soils, and on design variables such as embankment, heights and slopes, modification of upstream drainage, and revegetation practices. Generally, geomorphic evidence suggests that use of soil and vegetation alone will not be adequate to reduce erosion on slopes greater than about 5 to 9%.

Voorhees, L.D.; Sale, M.J.; Webb, J.W.; Mulholland, P.J.

1983-01-01

157

Determinants of male involvement in the prevention of mother-to-child transmission of HIV programme in Eastern Uganda: a cross-sectional survey  

PubMed Central

Background Mother-to-child transmission of HIV (MTCT) accounts for over 95% of all paediatric HIV infections worldwide. Several studies have shown that male participation in the antenatal care of their spouses together with couple counselling and testing for HIV, increases use of the interventions for HIV prevention. The prevention programme of MTCT (PMTCT) was launched in Uganda in 2000 and Mbale in 2002. Less than 10% of the pregnant women accepted antenatal HIV testing at Mbale Regional Referral Hospital in 2003; couple counselling and testing for HIV was low. Therefore, we conducted the study to determine the level of male involvement and identify its determinants in the PMTCT programme. Methods A cross-sectional survey of 388 men aged 18 years or more, whose spouses were attending antenatal care at Mbale Regional Referral Hospital, was conducted in Mbale district, Eastern Uganda. A male involvement index was constructed based on 6 questions. The survey was complemented by eight focus group discussions and five in-depth interviews. Results The respondents had a median age of 32 years (inter-quartile range, IQR: 28-37). The majority (74%) had a low male involvement index and only 5% of men accompanied their spouses to the antenatal clinic. Men who had attained secondary education were more likely to have a high male involvement index (OR: 1.9, 95% CI: 1.1-3.3) than those who had primary or no formal education. The respondents, whose occupation was driver (OR: 0.3, 95% CI: 0.1-0.7) or those who had fear of disclosure of their HIV sero-status results to their spouses (OR: 0.4, 95% CI: 0.2-0.8), were less likely to have a high male involvement index. Barriers to male involvement in the PMTCT programme were related to both the poor health system, to socio-economic factors and to cultural beliefs. Conclusions Structural and cultural barriers to men's involvement in the PMTCT programme in Mbale district were complex and interrelated. Community sensitization of men about the benefits of antenatal care and PMTCT and improving client-friendliness in the clinics needs to be prioritised in order to improve low male participation and mitigate the effect of socio-economic and cultural factors. PMID:20573250

2010-01-01

158

Regulation of hepatitis C virus polyprotein processing by signal peptidase involves structural determinants at the p7 sequence junctions.  

PubMed

The hepatitis C virus genome encodes a polyprotein precursor that is co- and post-translationally processed by cellular and viral proteases to yield 10 mature protein products (C, E1, E2, p7, NS2, NS3, NS4A, NS4B, NS5A, and NS5B). Although most cleavages in hepatitis C virus polyprotein precursor proceed to completion during or immediately after translation, the cleavages mediated by a host cell signal peptidase are partial at the E2/p7 and p7/NS2 sites, leading to the production of an E2p7NS2 precursor. The sequences located immediately N-terminally of E2/p7 and p7/NS2 cleavage sites can function as signal peptides. When fused to a reporter protein, the signal peptides of p7 and NS2 were efficiently cleaved. However, when full-length p7 was fused to the reporter protein, partial cleavage was observed, indicating that a sequence located N-terminally of the signal peptide reduces the efficiency of p7/NS2 cleavage. Sequence analyses and mutagenesis studies have also identified structural determinants responsible for the partial cleavage at both the E2/p7 and p7/NS2 sites. Finally, the short distance between the cleavage site of E2/p7 or p7/NS2 and the predicted transmembrane alpha-helix within the P' region might impose additional structural constraints to the cleavage sites. The insertion of a linker polypeptide sequence between P-3' and P-4' of the cleavage site released these constraints and led to improved cleavage efficiency. Such constraints in the processing of a polyprotein precursor are likely essential for hepatitis C virus to post-translationally regulate the kinetics and/or the level of expression of p7 as well as NS2 and E2 mature proteins. PMID:15247249

Carrère-Kremer, Séverine; Montpellier, Claire; Lorenzo, Lazaro; Brulin, Bénédicte; Cocquerel, Laurence; Belouzard, Sandrine; Penin, François; Dubuisson, Jean

2004-10-01

159

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

160

Evidence for involvement of 3'-untranslated region in determining angiotensin II receptor coupling specificity to G-protein.  

PubMed

The mRNA 3'-untranslated region (3'-UTR) of many genes has been identified as an important regulator of the mRNA transcript itself as well as the translated product. Previously, we demonstrated that Chinese-hamster ovary-K1 cells stably expressing angiotensin receptor subtypes (AT(1A)) with and without 3'-UTR differed in AT(1A) mRNA content and its coupling with intracellular signalling pathways. Moreover, RNA mobility-shift assay and UV cross-linking studies using the AT(1A) 3'-UTR probe identified a major mRNA-binding protein complex of 55 kDa in Chinese-hamster ovary-K1 cells. In the present study, we have determined the functional significance of the native AT(1A) receptor 3'-UTR in rat liver epithelial (WB) cell lines by co-expressing the AT(1A) 3'-UTR sequence 'decoy' to compete with the native receptor 3'-UTR for its mRNA-binding proteins. PCR analysis using specific primers for the AT(1A) receptor and [(125)I]angiotensin II (AngII)-binding studies demonstrated the expression of the native AT(1A) receptors in WB (B(max)=2.7 pmol/mg of protein, K(d)=0.56 nM). Northern-blot analysis showed a significant increase in native receptor mRNA expression in 3'-UTR decoy-expressing cells, confirming the role of 3'-UTR in mRNA destabilization. Compared with vehicle control, AngII induced DNA and protein synthesis in wild-type WB as measured by [(3)H]thymidine and [(3)H]leucine incorporation respectively. Activation of [(3)H]thymidine and [(3)H]leucine correlated with a significant increase in cell number (cellular hyperplasia). In these cells, AngII stimulated GTPase activity by AT(1) receptor coupling with G-protein alpha i. We also delineated that functional coupling of AT(1A) receptor with G-protein alpha i is an essential mechanism for AngII-mediated cellular hyperplasia in WB by specifically blocking G-protein alpha i activation. In contrast with wild-type cells, stable expression of the 3'-UTR 'decoy' produced AngII-stimulated protein synthesis and cellular hypertrophy as demonstrated by a significant increase in [(3)H]leucine incorporation and no increase in [(3)H]thymidine incorporation and cell number. Furthermore, [(125)I]AngII cross-linking and immunoprecipitation studies using specific G-protein alpha antibodies showed that in wild-type cells, the AT(1A) receptor coupled with G-protein alpha i, whereas in cells expressing the 3'-UTR 'decoy', the AT(1A) receptor coupled with G-protein alpha q. These findings indicate that the 3'-UTR-mediated changes in receptor function may be mediated in part by a switch from G-protein alpha i to G-protein alpha q coupling of the receptor. Our results suggest that the 3'-UTR-mediated post-transcriptional modification of the AT(1A) receptor is critical for regulating tissue-specific receptor functions. PMID:12431186

Thekkumkara, Thomas J; Linas, Stuart L

2003-03-01

161

Tail and Non-Tail Memory with Applications to Extreme Value and Robust Statistics  

Microsoft Academic Search

New notions of tail and non-tail dependence are used to characterize separately extremal and non-extremal information, including tail log-exceedances and events, and tail-trimmed levels. We prove Near Epoch Dependence (McLeish 1975, Gallant and White 1988) and L0-Approximability (Pötscher and Prucha 1991) are equivalent for tail events and tail-trimmed levels, ensuring a Gaussian central limit theory for important extreme value and

Jonathan B. Hilly

162

Is rhizosphere remediation sufficient for sustainable revegetation of mine tailings?  

PubMed Central

Background Revegetation of mine tailings (fine-grained waste material) starts with the reconstruction of root zones, consisting of a rhizosphere horizon (mostly topsoil and/or amended tailings) and the support horizon beneath (i.e. equivalent to subsoil – mostly tailings), which must be physically and hydro-geochemically stable. This review aims to discuss key processes involved in the development of functional root zones within the context of direct revegetation of tailings and introduces a conceptual process of rehabilitating structure and function in the root zones based on a state transition model. Scope Field studies on the revegetation of tailings (from processing base metal ore and bauxite residues) are reviewed. Particular focus is given to tailings' properties that limit remediation effectiveness. Aspects of root zone reconstruction and vegetation responses are also discussed. Conclusions When reconstructing a root zone system, it is critical to restore physical structure and hydraulic functions across the whole root zone system. Only effective and holistically restored systems can control hydro-geochemical mobility of acutely and chronically toxic factors from the underlying horizon and maintain hydro-geochemical stability in the rhizosphere. Thereafter, soil biological capacity and ecological linkages (i.e. carbon and nutrient cycling) may be rehabilitated to integrate the root zones with revegetated plant communities into sustainable plant ecosystems. A conceptual framework of system transitions between the critical states of root zone development has been proposed. This will illustrate the rehabilitation process in root zone reconstruction and development for direct revegetation with sustainable plant communities. Sustainable phytostabilization of tailings requires the systematic consideration of hydro-geochemical interactions between the rhizosphere and the underlying supporting horizon. It further requires effective remediation strategies to develop hydro-geochemically stable and biologically functional root zones, which can facilitate the recovery of the microbial community and ecological linkages with revegetated plant communities. PMID:22648878

Huang, Longbin; Baumgartl, Thomas; Mulligan, David

2012-01-01

163

Characterization of Emergent Data Networks Among Long-Tail Data  

NASA Astrophysics Data System (ADS)

Data curation underpins data-driven scientific advancements. It manages the information flux across multiple users throughout data life cycle as well as increases data sustainability and reusability. The exponential growth in data production spanning across the Earth Science involving individual and small research groups, which is termed as log-tail data, increases the data-knowledge latency among related domains. It has become clear that an advanced framework-agnostic metadata and ontologies for long-tail data is required to increase their visibility to each other, and provide concise and meaningful descriptions that reveal their connectivity. Despite the advancement that has been achieved by various sophisticated data management models in different Earth Science disciplines, it is not always straightforward to derive relationships among long-tail data. Semantic data clustering algorithms and pre-defined logic rules that are oriented toward prediction of possible data relationships, is one method to address these challenges. Our work advances the connectivity of related long-tail data by introducing the design for an ontology-based knowledge management system. In this work, we present the system architecture, its components, and illustrate how it can be used to scrutinize the connectivity among datasets. To demonstrate the capabilities of this "data network" prototype, we implemented this approach within the Sustainable Environment Actionable Data (SEAD) environment, an open-source semantic content repository that provides a RDF database for long-tail data, and show how emergent relationships among datasets can be identified.

Elag, Mostafa; Kumar, Praveen; Hedstrom, Margaret; Myers, James; Plale, Beth; Marini, Luigi; McDonald, Robert

2014-05-01

164

Oxidation of sulphide in abandoned mine tailings by ferrate.  

PubMed

In this study, Fe(VI) was applied to treat three mine tailings containing different amounts of sulphides and heavy metals. Oxidation of sulphides by Fe(VI) was studied at pH 9.2 with variation of solid to solution ratio, Fe(VI) concentration and injection number of Fe(VI) solution. The major dissolved products from the treatment of mine tailings with Fe(VI) solution were sulphate and arsenic. Oxidation efficiency of sulphides was evaluated by reduction efficiency of Fe(VI) as well as by measurement of dissolved sulphate concentration. Even though inorganic composition of three mine tailings was different, reduction fraction of Fe(VI) was quite similar. This result can suggest that Fe(VI) was involved in several other reactions in addition to oxidation of sulphides. Oxidation of sulphides in mine tailing was greatly dependent on the total amount of sulphides as well as kinds of sulphides complexed with metals. Over the five consecutive injections of Fe(VI) solution, dissolved sulphate concentration was greatly decreased by each injection and no more dissolved sulphate was observed at the fifth injection. While dissolved arsenic was decreased lineally up to the fifth injection. Sulphate generation was slightly increased for all mine tailings as Fe(VI) concentration was increased; however, enhancement of oxidation efficiency of sulphides was not directly proportional to the initial Fe(VI) concentration. PMID:25413120

Lee, Yong-Hoon; Yu, Mok-Ryun; Chang, Yoon-Young; Kang, Seon-Hong; Yang, Jae-Kyu

2015-01-01

165

The tail sheath structure of bacteriophage T4: a molecular machine for infecting bacteria  

SciTech Connect

The contractile tail of bacteriophage T4 is a molecular machine that facilitates very high viral infection efficiency. Its major component is a tail sheath, which contracts during infection to less than half of its initial length. The sheath consists of 138 copies of the tail sheath protein, gene product (gp) 18, which surrounds the central non-contractile tail tube. The contraction of the sheath drives the tail tube through the outer membrane, creating a channel for the viral genome delivery. A crystal structure of about three quarters of gp18 has been determined and was fitted into cryo-electron microscopy reconstructions of the tail sheath before and after contraction. It was shown that during contraction, gp18 subunits slide over each other with no apparent change in their structure.

Aksyuk, Anastasia A.; Leiman, Petr G.; Kurochkina, Lidia P.; Shneider, Mikhail M.; Kostyuchenko, Victor A.; Mesyanzhinov, Vadim V.; Rossmann, Michael G.; (SOIBC); (Purdue)

2009-07-22

166

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

167

Abaxial tail attachment of bovine spermatozoa and its effect on fertility  

PubMed Central

The prevalence of abaxial sperm tails, accessory tails and double tails, was determined from semen evaluation records of 600 western Canadian range bulls and 449 bulls in Canadian artificial insemination centers. Spermatozoa with abaxial tails were produced by 10.5% of bulls, however, only 0.48% produced sperm with greater than 50% abaxial tails, and 0.86% of the 1049 bulls produced sperm with accessory and double tails. Three experiments were done to determine the importance of abaxial sperm tails to fertility. In experiments 1 and 2, frozen semen with 88%, 50% and 0% abaxial tails was used to inseminate synchronized heifers, which were allowed to develop pregnancy, and superovulated heifers, which were slaughtered prior to embryo recovery seven days after breeding. In experiment 3, a bull which produced 100% abaxial sperm was used in a competitive mating situation with three control bulls in a herd of 118 cows. The combined results of these experiments indicate that spermatozoa with abaxial tail attachment fertilize ova at a normal rate and are not associated with any increase in embryonic death. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6. PMID:17423394

Barth, Albert D.

1989-01-01

168

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

169

Liquid Chromatographic Detection of Permethrin from Filter Paper Wipes of White-tailed Deer  

Technology Transfer Automated Retrieval System (TEKTRAN)

A simple, small-scale method for the determination of the presence or absence of permethrin on the hair coat of white-tailed deer, Odocoileus virginianus (Zimmermann), by high performance liquid chromatography was developed. White-tailed deer in South Texas and the northeastern U.S. are routinely tr...

170

Design of an MR Based on Device for the Adaptive Stiffness Control of Tail Shafts  

Microsoft Academic Search

Vertical tail design is driven by many elements concerning directional stability and directional control. The overall size of a vertical tail is mainly determined by the stability requirements, while its design is guided by structural constraints, and the rudder configuration and size is mainly linked to the established control characteristics. From the statements above, it follows that reducing the size

S. Ameduri; A. Concilio; A. Gianvito

2009-01-01

171

Quantitative arsenic speciation in mine tailings using X-ray absorption spectroscopy  

Microsoft Academic Search

X-ray absorption fine structure spectroscopy (XAFS) was used to determine arsenic (As) oxidation state, local coordination (to a radius of 7Aaround As), and the relative proportion of different As species in model compounds and three California mine wastes: fully oxidized tailings (Ruth Mine), partially oxidized tailings (Argonaut Mine), and roast- ed sulfide ore (Spenceville Mine). Mineralogy was characterized by Rietveld

ANDREA L. FOSTER; GORDON E. BROWN JR; TRACY N. TINGLE; GEORGE A. PARKS

172

Black-Tailed Prairie Dog  

USGS Multimedia Gallery

Black-tailed prairie dogs are quite susceptible to sylvatic plague, but a new plague vaccine put in their food shows significant promise in the laboratory. The prairie dogs transmit the disease to endangered black-footed ferrets, who eat the prairie dogs and are also quite susceptible to the disease...

173

The Crystal Structure of Bacteriophage HK97 gp6: Defining a Large Family of Head?Tail Connector Proteins  

SciTech Connect

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 {angstrom} 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.

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. (UHN); (Toronto); (Hauptman)

2010-08-17

174

Tail use in bioinspired quadrupedal locomotion  

E-print Network

Tails are seen in nature to be used in an amazing number of different applications. Many of these applications seen in nature may be of use to bioinspired roboticists in the future. I have provided a brief review of tail ...

Briggs, Randall (Randall Miller)

2012-01-01

175

Lobster Tail Ice Formation on Aerosurface  

NASA Technical Reports Server (NTRS)

Glace Ice formation commonly refered to as 'Lobster Tail' by scientists and engineers, is caused to form on the leading edge of a aircraft tail section in the icing research tunnel at the NASA Glenn Research Center, Cleveland, Ohio.

1999-01-01

176

The localization of protein carboxyl-methylase in sperm tails  

PubMed Central

Protein carboxyl-methylase (PCM), an enzyme known to be involved in exocytotic secretion and chemotaxis, has been studied in rat and rabbit spermatozoa. PCM activity and its substrate methyl acceptor protein(s) (MAP) were demonstrated in the supernate after solubilization of the sperm cell membrane by detergent (Triton X-100). A protein methylesterase that hydrolyzes methyl ester bonds created by PCM was demonstrated in rabbit but not in rat spermatozoa. This enzyme was not solubilized by nonionic detergent. The specific activities of PCM in rat spermatozoa from caput and cauda epididymis were similar and lower than that found in testis. By contrast, MAP substrates were low in testis and increased in parallel with sperm maturation in the epididymis. Multiple MAP were demonstrated in spermatozoa by polyacrylamide gel electrophoresis. The pattern of these proteins was similar in spermatozoa from different portions of the reproductive tract. Fractionation of heads and tails of rat spermatozoa on sucrose gradients indicated that PCM was found exclusively in the tail fraction, whereas MAP was detected both in head and tail fractions. The presence of all the components of the protein carboxyl-methylation system in spermatozoa and the localization of PCM and some of its substrates in the sperm tail are consistent with their involvement in sperm cell motility. PMID:7400214

1980-01-01

177

Analysis of Imp-C data from the magnetospheric tail  

NASA Technical Reports Server (NTRS)

Satellite magnetic field measurements in the geomagnetic tail current sheet are analyzed to determine the normal field component, and other CS parameters such as thickness, motion, vector current density, etc., and to make correlations with auroral activity as measured by the A sub e index. The satellite data used in the initial part of this study were from Explorer 28 and Explorer 34 satellites.

Speiser, T. W.

1973-01-01

178

Descending from infinity: Convergence of tailed distributions  

NASA Astrophysics Data System (ADS)

We investigate the relaxation of long-tailed distributions under stochastic dynamics that do not support such tails. Linear relaxation is found to be a borderline case in which long tails are exponentially suppressed in time but not eliminated. Relaxation stronger than linear suppresses long tails immediately, but may lead to strong transient peaks in the probability distribution. We also find that a ? -function initial distribution under stronger than linear decay displays not one but two different regimes of diffusive spreading.

Van den Broeck, Christian; Harbola, Upendra; Toral, Raul; Lindenberg, Katja

2015-01-01

179

A quantitative and humane tail bleeding assay for efficacy evaluation of antihaemophilic factors in haemophilia A mice.  

PubMed

The tail bleeding model using haemophilic mice has been used as one of the standard assays for efficacy evaluation of novel antihaemophilic therapies at the preclinical level. A number of different configurations and endpoints have been proposed in the literature for this model, hindering interlaboratory comparisons. A particular configuration, known as the tail bleeding survival assay (TBS), adopted by several groups, involves measuring the ability of conscious haemophilic mice to survive exsanguination following tail transection. Major limitations to this configuration include ethical constraints and impaired quantitative determinations. The aim of this study was to standardize and validate a quantitative haemostatic assay for evaluation of antihaemophilic therapies employing an alternative to TBS, which involves a more humane endpoint associated with stable clot formation. Haemophilic mice were treated with vehicle or different doses of two antihaemophilic reference products licensed in Brazil. The haemostatic response was evaluated by our quantitative tail bleeding haemostatic assay (qTBA) over a period of 120 min and then quantified by dose-response modelling. We demonstrate that our qTBA method allows a direct relationship between the number of animals which achieved full haemostatic response and the dosage of both antihaemophilic factors evaluated over 120 min. In addition, the method sensitivity is suitable to demonstrate the conversion from a severe to a moderate haemophilia phenotype. Our proposed qTBA is easy to implement and constitutes an alternative and more ethical endpoint, which could be effectively used as a surrogate to the commonly employed survival endpoint, allowing quantitative haemostatic response evaluation associated with stable clot formation. PMID:24975823

Molina, E S; Fujita, A; Sogayar, M C; Demasi, M A

2014-11-01

180

On the shape of the Geomagnetic Tail at Lunar distances: Preliminary Resuts from Artemis Observations  

NASA Astrophysics Data System (ADS)

Geomagnetic tail is one of the least investigated regions of the magnetosphere behind the Earth owing to the limited number of spacecraft and observations. It is the region where the geomagnetic dipole field lines of the Earth are organized by the solar wind stretching. The characteristics of the geomagnetic tail and its response to IMF were studied by the missions, ISEE-3, IMP-8, Wind, Geotail, visited geomagnetic tail at different distances. The structure of the geomagnetic tail is controlled by the IMF orientation and its own internal dynamics. Geomagnetic tail has different regions where the plasma and magnetic field characteristics are largely depend on the IMF orientation. These characteristics show differences at different tail distances. For example it is determined that the tail twists as result of the reconnection with IMF By and this twist is higher as one move away from the Earth toward the distant tail. Like a windsock, it is expected that the IMF control will increase toward the distant tail. Twisting also displaces the north and south lobes on the dawn and dusk sides. Tail length and the shape are also different for different IMF orientations. Flattening of the geomagnetic tail cross-section occurs during the strong IMF Bys. It becomes an ellipse in the yz plane as the IMF By stress causes the tail to be flattened on the top and bottom. Models estimate that the geomagnetic tail length can be 165 Re while Pioneer spacecraft detected geomagnetic tail as long as 100 Re. These findings are based on the very limited data from brief geomagnetic tail encounters of the spacecraft. Since August 2011, with the repositioning of the two of THEMIS spacecraft pair, ARTEMIS is giving a new opportunity to study the geomagnetic tail at the lunar distances, 60 Re. Using these observations, we will investigate the geomagnetic field shape and its IMF dependence at 60 Re. Based on the magnetopause locations at 60 Re, we will study the shape of the tail on the xy-plane. Available analytical models and the numerical model results will be tested and used to find the best model at lunar distances. In this study, we will present our preliminary results and compare our findings with those from the earlier studies in the literature.

Gencturk Akay, Iklim; Kaymaz, Zerefsan; Sibeck, David G.

2013-04-01

181

A Phenotypic Screen in Zebrafish Identifies a Novel Small-Molecule Inducer of Ectopic Tail Formation Suggestive of Alterations in Non-Canonical Wnt/PCP Signaling  

PubMed Central

Zebrafish have recently emerged as an attractive model for the in vivo bioassay-guided isolation and characterization of pharmacologically active small molecules of natural origin. We carried out a zebrafish-based phenotypic screen of over 3000 plant-derived secondary metabolite extracts with the goal of identifying novel small-molecule modulators of the BMP and Wnt signaling pathways. One of the bioactive plant extracts identified in this screen – Jasminum gilgianum, an Oleaceae species native to Papua New Guinea – induced ectopic tails during zebrafish embryonic development. As ectopic tail formation occurs when BMP or non-canonical Wnt signaling is inhibited during the tail protrusion process, we suspected a constituent of this extract to act as a modulator of these pathways. A bioassay-guided isolation was carried out on the basis of this zebrafish phenotype, identifying para-coumaric acid methyl ester (pCAME) as the active compound. We then performed an in-depth phenotypic analysis of pCAME-treated zebrafish embryos, including a tissue-specific marker analysis of the secondary tails. We found pCAME to synergize with the BMP-inhibitors dorsomorphin and LDN-193189 in inducing ectopic tails, and causing convergence-extension defects in compound-treated embryos. These results indicate that pCAME may interfere with non-canonical Wnt signaling. Inhibition of Jnk, a downstream target of Wnt/PCP signaling (via morpholino antisense knockdown and pharmacological inhibition with the kinase inhibitor SP600125) phenocopied pCAME-treated embryos. However, immunoblotting experiments revealed pCAME to not directly inhibit Jnk-mediated phosphorylation of c-Jun, suggesting additional targets of SP600125, and/or other pathways, as possibly being involved in the ectopic tail formation activity of pCAME. Further investigation of pCAME’s mechanism of action will help determine this compound’s pharmacological utility. PMID:24349481

Gebruers, Evelien; Cordero-Maldonado, María Lorena; Gray, Alexander I.; Clements, Carol; Harvey, Alan L.; Edrada-Ebel, Ruangelie; de Witte, Peter A. M.; Crawford, Alexander D.; Esguerra, Camila V.

2013-01-01

182

A phenotypic screen in zebrafish identifies a novel small-molecule inducer of ectopic tail formation suggestive of alterations in non-canonical Wnt/PCP signaling.  

PubMed

Zebrafish have recently emerged as an attractive model for the in vivo bioassay-guided isolation and characterization of pharmacologically active small molecules of natural origin. We carried out a zebrafish-based phenotypic screen of over 3000 plant-derived secondary metabolite extracts with the goal of identifying novel small-molecule modulators of the BMP and Wnt signaling pathways. One of the bioactive plant extracts identified in this screen - Jasminum gilgianum, an Oleaceae species native to Papua New Guinea - induced ectopic tails during zebrafish embryonic development. As ectopic tail formation occurs when BMP or non-canonical Wnt signaling is inhibited during the tail protrusion process, we suspected a constituent of this extract to act as a modulator of these pathways. A bioassay-guided isolation was carried out on the basis of this zebrafish phenotype, identifying para-coumaric acid methyl ester (pCAME) as the active compound. We then performed an in-depth phenotypic analysis of pCAME-treated zebrafish embryos, including a tissue-specific marker analysis of the secondary tails. We found pCAME to synergize with the BMP-inhibitors dorsomorphin and LDN-193189 in inducing ectopic tails, and causing convergence-extension defects in compound-treated embryos. These results indicate that pCAME may interfere with non-canonical Wnt signaling. Inhibition of Jnk, a downstream target of Wnt/PCP signaling (via morpholino antisense knockdown and pharmacological inhibition with the kinase inhibitor SP600125) phenocopied pCAME-treated embryos. However, immunoblotting experiments revealed pCAME to not directly inhibit Jnk-mediated phosphorylation of c-Jun, suggesting additional targets of SP600125, and/or other pathways, as possibly being involved in the ectopic tail formation activity of pCAME. Further investigation of pCAME's mechanism of action will help determine this compound's pharmacological utility. PMID:24349481

Gebruers, Evelien; Cordero-Maldonado, María Lorena; Gray, Alexander I; Clements, Carol; Harvey, Alan L; Edrada-Ebel, Ruangelie; de Witte, Peter A M; Crawford, Alexander D; Esguerra, Camila V

2013-01-01

183

Uranium mill tailings quarterly report, January-March 1982  

SciTech Connect

Progress is reported on: radon barrier systems for uranium mill tailings; liner evaluation for uranium mill tailings; revegetation/rock cover for stabilization of inactive U-tailings sites; and application of long-term chemical biobarriers for uranium tailings.

Latkovich, J.M. (comp.)

1982-05-01

184

Intracellular phospholipase A1 and acyltransferase, which are involved in Caenorhabditis elegans stem cell divisions, determine the sn-1 fatty acyl chain of phosphatidylinositol.  

PubMed

Phosphatidylinositol (PI), an important constituent of membranes, contains stearic acid as the major fatty acid at the sn-1 position. This fatty acid is thought to be incorporated into PI through fatty acid remodeling by sequential deacylation and reacylation. However, the genes responsible for the reaction are unknown, and consequently, the physiological significance of the sn-1 fatty acid remains to be elucidated. Here, we identified acl-8, -9, and -10, which are closely related to each other, and ipla-1 as strong candidates for genes involved in fatty acid remodeling at the sn-1 position of PI. In both ipla-1 mutants and acl-8 acl-9 acl-10 triple mutants of Caenorhabditis elegans, the stearic acid content of PI is reduced, and asymmetric division of stem cell-like epithelial cells is defective. The defects in asymmetric division of these mutants are suppressed by a mutation of the same genes involved in intracellular retrograde transport, suggesting that ipla-1 and acl genes act in the same pathway. IPLA-1 and ACL-10 have phospholipase A(1) and acyltransferase activity, respectively, both of which recognize the sn-1 position of PI as their substrate. We propose that the sn-1 fatty acid of PI is determined by ipla-1 and acl-8, -9, -10 and crucial for asymmetric divisions. PMID:20668164

Imae, Rieko; Inoue, Takao; Kimura, Masako; Kanamori, Takahiro; Tomioka, Naoko H; Kage-Nakadai, Eriko; Mitani, Shohei; Arai, Hiroyuki

2010-09-15

185

On tail behavior of nonlinear autoregressive functional conditional heteroscedastic model with heavy-tailed innovations  

Microsoft Academic Search

We study the tail probability of the stationary distribution of nonparametric nonlinear autoregressive functional conditional\\u000a heteroscedastic (NARFCH) model with heavy-tailed innovations. Our result shows that the tail of the stationary marginal distribution\\u000a of an NARFCH series is heavily dependent on its conditional variance. When the innovations are heavy-tailed, the tail of the\\u000a stationary marginal distribution of the series will become

Jiazhu Pan; Guangxu Wu

2005-01-01

186

Effects of tail span and empennage arrangement on drag of a typical single-engine fighter aft end  

NASA Technical Reports Server (NTRS)

An investigation was conducted in the Langley 16 foot Transonic Tunnel to determine the effects of tail span and empennage arrangement on drag of a single engine nozzle/afterbody model. Tests were conducted at Mach numbers from 0.50 to 1.20, nozzle pressures frm 1.0 (jet off) to 8.0, and angles of attack from -3 to 9 deg, depending upon Mach numbers. Three empennage arrangements (aft, staggered, and forward) were investigated with several different tail spans. The results of the investigation indicate that tail span and position have a significant effect on the drag at transonic speeds. Unfavorable tail interference was largely due to the outer portion of the tail surfaces. The inner portion near the nozzle and afterbody did little to increase drag other than surface skin friction. Tail positions forward of the nozzle generally had lower tail interference.

Burley, J. R., II; Berrier, B. L.

1984-01-01

187

Long-Term Performance of Uranium Tailings Disposal Cells - 13340  

SciTech Connect

Recently, there has been interest in the performance and evolution of Uranium Mill Tailings Remedial Action (UMTRA) Project disposal cell covers because some sites are not compliant with groundwater standards. Field observations of UMTRA disposal cells indicate that rock covers tend to become vegetated and that saturated conductivities in the upper portion of radon barriers may increase due to freeze/thaw cycles and biointrusion. This paper describes the results of modeling that addresses whether these potential changes and transient drainage of moisture in the tailings affect overall performance of the disposal cells. A numerical unsaturated/saturated 3-dimensional flow model was used to simulate whether increases in saturated conductivities in radon barriers with rock covers affect the overall performance of the disposal cells using field data from the Shiprock, NM, UMTRA site. A unique modeling approach allowed simulation with daily climatic conditions to determine changes in moisture and moisture flux from the disposal cell. Modeling results indicated that increases in the saturated conductivity at the top of radon barrier do not influence flux from the tailings with time because the tailings behave similar hydraulically to the radon barrier. The presence of a thin layer of low conductivity material anywhere in the cover or tailings restricts flux in the worst case to the saturated conductivity of that material. Where materials are unsaturated at depth within the radon barrier of tailings slimes, conductivities are typically less than 10{sup -8} centimeters per second. If the low conductivity layer is deep within the disposal cell, its saturated properties are less likely to change with time. The significance of this modeling is that operation and maintenance of the disposal cells can be minimized if they are allowed to progress to a natural condition with some vegetation and soil genesis. Because the covers and underlying tailings have a very low saturated hydraulic conductivity after transient drainage, eventually the amount of moisture leaving the tailings has a negligible effect on groundwater quality. Although some of the UMTRA sites are not in compliance with the groundwater standards, the explanation may be legacy contamination from mining, or earlier higher fluxes from the tailings or unlined processing ponds. Investigation of other legacy sources at the UMTRA sites may help explain persistent groundwater contamination. (authors)

Bostick, Kent; Daniel, Anamary; Pill, Ken [Professional Project Services, Inc., 1100 Bethel Valley Road, Oak Ridge, TN, 37922 (United States)] [Professional Project Services, Inc., 1100 Bethel Valley Road, Oak Ridge, TN, 37922 (United States); Tachiev, Georgio; Noosai, Nantaporn; Villamizar, Viviana [Florida International University, 10555 W. Flagler St., EC 2100, Miami FL, 33174 (United States)] [Florida International University, 10555 W. Flagler St., EC 2100, Miami FL, 33174 (United States)

2013-07-01

188

Bearing capacity of desiccated tailings  

Microsoft Academic Search

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

Daud W. Rassam; David J. Williams

1999-01-01

189

Uranium mill tailings remedial action project real estate management plan  

SciTech Connect

This plan summarizes the real estate requirements of the US Department of Energy`s (DOE) Uranium Mill Tailings Action (UMTRA) Project, identifies the roles and responsibilities of project participants involved in real estate activities, and describes the approaches used for completing these requirements. This document is intended to serve as a practical guide for all project participants. It is intended to be consistent with all formal agreements, but if a conflict is identified, the formal agreements will take precedence.

Not Available

1994-09-01

190

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 that…

Fox-Parrish, Lynne; Jurin, Richard R.

2008-01-01

191

Adsorption of trace elements on pyrite surfaces in sulfidic mine tailings from Kristineberg (Sweden) a few years after remediation  

Microsoft Academic Search

Laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) has been used to determine the elemental composition of the surface and interior layers of pyrite grains from the mine tailings from Kristineberg (northern Sweden) in order to determine concentration gradients between these two layers. The pyrite grains were collected from oxidized and unoxidized zones within the tailings. The aim of

Barbara Müller; Mikael D Axelsson; Björn Öhlander

2002-01-01

192

The hydrogeology of a tailings impoundment formed by central discharge of thickened tailings: implications for tailings management  

NASA Astrophysics Data System (ADS)

The Kidd Creek Cu-Zn sulfide mine is located near Timmins, Ontario. Mill tailings are thickened and deposited as a slurry in a circular impoundment with an area of approximately 1200 ha. Deposition of tailings as a thickened slurry from a central discharge ramp results in a conical-shaped tailings deposit with low perimeter dykes, a uniform grain-size distribution, uniform and low hydraulic conductivity, and a tension-saturated zone above the water table up to 5 to 6 m thick. These characteristics provide benefits over conventionally disposed tailings with respect to tailings management. The thick tension-saturated zone within the tailings limits the thickness of unsaturated tailings that are susceptible to rapid sulfide oxidation. The conical shape of the deposit results in the formation of a recharge area near the centre of the impoundment and discharge in the peripheral areas. In contrast, the elevated nature of many conventional, unthickened tailings impoundments results in recharge over most of the surface of the impoundment, with discharge occurring outside the impoundment through large containment dykes. Three-dimensional pore water flow modelling suggests that approximately 90% of the total discharge from the thickened tailings occurs within the tailings impoundment. When discharge is confined within the impoundment, there is improved control over low-quality effluent, and an opportunity to design passive control measures to reduce treatment costs and minimize environmental impacts.

Al, Tom A.; Blowes, David W.

1999-06-01

193

Storm-water hydrograph separation of run off from a mine-tailings impoundment formed by thickened tailings discharge at Kidd Creek, Timmins, Ontario  

NASA Astrophysics Data System (ADS)

The Kidd Creek Cu?Zn sulphide mine is located near Timmins, Ontario. Mill tailings are thickened and deposited as a thickened slurry in a circular, conical-shaped pile with an area of approximately 1200 ha. Deposition of tailings as a thickened slurry results in a relatively uniform grain-size distribution and hydraulic conductivity, and a thick tension-saturated zone above the water table. The tailings are drained by numerous small, ephemeral stream channels, which have developed in a radial pattern. During storms, water from these streams collects in catchment ponds where it is held before treatment. The contribution of tailings pore water to the run off is of interest because of the potential for discharge of pore water containing high concentrations of Fe(II)-acidity, metals and SO 4 to the stream. Hydraulic head measurements, measurements of water-table elevation and groundwater flow modelling were conducted to determine the mechanisms responsible for tailings pore water entering the surface streams. Chemical hydrograph separation of storm run off in one of these streams, during three rainfall events, using Na and Cl as conservative tracers, indicates that the integrated tailings pore water fraction makes up between less than 1 % and 20% of the total hydrograph. This range is less than the maximum fraction of tailings pore water of 22-65% reported for run off from a conventional tailings deposit. At this site, preferential flow through permeable fractures may be the dominant mechanism causing discharge of tailings pore water to storm run off. Estimates of the mass of Fe(II) that discharges to the surface run off from the pore water range up to 2800 mg s -1 during a moderate intensity, long duration rainfall event. The greatest potential for discharge of significant masses of solutes derived from the pore water exists during long duration rainfall events, when the water table rises to the surface over large areas of the tailings impoundment.

Al, Tom A.; Blowes, David W.

1996-05-01

194

ICAM-1 cytoplasmic tail regulates endothelial glutathione synthesis through a NOX4/PI3-kinase-dependent pathway  

PubMed Central

We previously reported that ICAM-1 expression modulates endothelial intracellular glutathione (GSH) metabolism through unknown mechanisms. Here we report that the cytoplasmic tail of ICAM-1 is critically involved in governing intracellular GSH production. Peptides containing the antennapedia cell-permeative sequence (AP) or an AP peptide linked to the transmembrane and cytosolic tail of ICAM-1 (AP-ICAM) were synthesized and used to measure alterations in redox status in cultured endothelial cells and determine their biological effect. Treatment with AP-ICAM significantly increased GSH concentrations and glutamate–cysteine ligase (GCL) activity over time. Measuring reactive oxygen species (ROS) production with DCF revealed a rapid increase in ROS generation after AP-ICAM treatment. Measurement of superoxide production with hydroethidium revealed biphasic production at 30 min and 6 h after treatment with AP-ICAM. Apocynin, DPI, catalase, or SOD attenuated AP-ICAM-dependent ROS production, GCL activity, and GSH production, implicating superoxide production and dismutation to peroxide. Consistent with these findings, NOX4 siRNA knockdown blocked AP-ICAM peptide increases in GSH or GCL activity, demonstrating the importance of NADPH oxidase. Last, inhibition of PI3-kinase activity with LY 294002 or wortmannin blocked AP-ICAM GSH induction and ROS production. These data reveal that the ICAM-1 cytoplasmic tail regulates production of endothelial GSH through a NOX4/PI3-kinase-dependent redox-sensitive pathway. PMID:20633529

Pattillo, Christopher B.; Pardue, Sibile; Shen, Xinggui; Fang, Kai; Langston, Will; Jourd'heuil, David; Kavanagh, Terrance J.; Patel, Rakesh P.; Kevil, Christopher G.

2014-01-01

195

Spectral induced polarization (SIP) response of mine tailings.  

PubMed

Mine tailings impoundments are a source of leachates known as acid mine drainage (AMD) which can pose a contamination risk for surrounding surface and groundwater. Methodologies which can help management of this environmental issue are needed. We carried out a laboratory study of the spectral induced polarization (SIP) response of tailings from the Haveri Au-Cu mine, SW Finland. The primary objectives were, (1) to determine possible correlations between SIP parameters and textural properties associated with oxidative-weathering mechanisms, mineralogical composition and metallic content, and (2) to evaluate the effects of the pore water chemistry on SIP parameters associated with redox-inactive and redox-active electrolytes varying in molar concentration, conductivity and pH. The Haveri tailings exhibit well defined relaxation spectra between 100 and 10,000Hz. The relaxation magnitudes are governed by the in-situ oxidative-weathering conditions on sulphide mineral surfaces contained in the tailings, and decrease with the oxidation degree. The oxidation-driven textural variation in the tailings results in changes to the frequency peak of the phase angle, the imaginary conductivity and chargeability, when plotted versus the pore water conductivity. In contrast, the real and the formation electrical conductivity components show a single linear dependence on the pore water conductivity. The increase of the pore water conductivity (dominated by the increase of ions concentration in solution) along with a transition to acidic conditions shifts the polarization peak towards higher frequencies. These findings show the unique sensitivity of the SIP method to potentially discriminate AMD discharges from reactive oxidation zones in tailings, suggesting a significant advantage for monitoring threatened aquifers. PMID:25528133

Placencia-Gómez, Edmundo; Parviainen, Annika; Slater, Lee; Leveinen, Jussi

2015-02-01

196

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

2006-11-01

197

Tail probabilities for non-standard risk and queueing processes with subexponential jumps  

Microsoft Academic Search

A well-known result on the distribution tail of the maximum of a random walk with\\u000aheavy-tailed increments is extended to more general stochastic processes. Results are\\u000agiven in different settings, involving, for example, stationary increments and\\u000aregeneration. Several examples and counterexamples illustrate that the conditions of\\u000athe theorems can easily be verified in practice and are in part necessary. The

Søren Asmussen; Hanspeter Schmidli; Volker Schmidt

1999-01-01

198

A perfect knowledge of the effects of chromosomal abnormalities in domestic animal requi-res an exact determination of the chromosome involved in each type of translocation as well as  

E-print Network

A perfect knowledge of the effects of chromosomal abnormalities in domestic animal requi- res an exact determination of the chromosome involved in each type of translocation as well, the occurate identification by means of new banding methods of the chromosomes involved in each type

Paris-Sud XI, Université de

199

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

2010-08-01

200

Application of STR markers in wildlife forensic casework involving Australian black-cockatoos (Calyptorhynchus spp.).  

PubMed

Parrots and cockatoos are highly prized aviary birds and the demands for such species has fuelled their illegal trade and harvest from the wild. Here we report on three forensic case studies involving black-cockatoos (Calyptorhynchus spp.) endemic to Australia. These cases involve suspected poaching and illegal killing of endangered red- and white-tailed black-cockatoos. Through the prior development of 20 polymorphic microsatellite loci and population databases for white- and red-tailed black-cockatoos, the tools are available to conduct high-resolution paternity and individual identity testing. In one case, we matched a red-tailed black-cockatoo nestling to a tree hollow from which it was poached through the use of DNA from eggshell recovered from the nest. For the second case, we utilized our provenance population database (nest sites), and identified the kinship and geographic origin of a white-tailed black-cockatoo, which was illegally harvested from the wild. The third case determined the number individual white-tailed black-cockatoos allegedly shot at a fruit grower's orchard from body part remains. These genetic investigations highlight the significance and statistical confidence of DNA profiling and associated databases for endangered taxa, such as exotic birds. Our cockatoo population databases are the first of their kind in Australia, and demonstrate the efficacy of such approaches to identify such illegal activity. With a robust set of genetic markers and methodologies in place, we aim to broaden our population databases to include other cockatoo species of conservation concern. PMID:22101117

White, Nicole E; Dawson, Rick; Coghlan, Megan L; Tridico, Silvana R; Mawson, Peter R; Haile, James; Bunce, Michael

2012-09-01

201

Molecularly imprinted electrochemical biosensor based on Fe@Au nanoparticles involved in 2-aminoethanethiol functionalized multi-walled carbon nanotubes for sensitive determination of cefexime in human plasma.  

PubMed

The molecular imprinting technique depends on the molecular recognition. It is a polymerization method around the target molecule. Hence, this technique creates specific cavities in the cross-linked polymeric matrices. In present study, a sensitive imprinted electrochemical biosensor based on Fe@Au nanoparticles (Fe@AuNPs) involved in 2-aminoethanethiol (2-AET) functionalized multi-walled carbon nanotubes (f-MWCNs) modified glassy carbon (GC) electrode was developed for determination of cefexime (CEF). The results of X-ray photoelectron spectroscopy (XPS) and reflection-absorption infrared spectroscopy (RAIRS) confirmed the formation of the developed surfaces. CEF imprinted film was constructed by cyclic voltammetry (CV) for 9 cycles in the presence of 80 mM pyrrole in phosphate buffer solution (pH 6.0) containing 20mM CEF. The developed electrochemical biosensor was validated according to the International Conference on Harmonisation (ICH) guideline and found to be linear, sensitive, selective, precise and accurate. The linearity range and the detection limit were obtained as 1.0 × 10(-10)-1.0 × 10(-8)M and 2.2 × 10(-11)M, respectively. The developed CEF imprinted sensor was successfully applied to real samples such as human plasma. In addition, the stability and reproducibility of the prepared molecular imprinted electrode were investigated. The excellent long-term stability and reproducibility of the prepared CEF imprinted electrodes make them attractive in electrochemical sensors. PMID:24832202

Yola, Mehmet Lütfi; Eren, Tanju; Atar, Necip

2014-10-15

202

Weathering in coal mine rejects and tailings - variation with respect to depth  

SciTech Connect

Acid production or acid drainage is a major environmental issue that also has negative implications on the aquifer system surrounding the mine tailings area. The approach to controlling acid mine drainage involves physical and geochemical characterization that affect acid production. The material permeability determines the availability of oxygen, which is paramount in acid production in coal rejects, and varies with depth. In this paper the author presents the variation in oxidized pyrite/acid production with depth in black coal mine washery wastes. Chemical kinetic parameters and the diffusive parameters have been used to obtain the variation in oxygen content and the oxidized pyrite content with respect to the depth and time. Its dependence on porosity and moisture content is illustrated.

Devasahayam, S.

2007-02-15

203

Fluctuations and Correlations in Physical and Biological Nanosystems: The Tale is in the Tails  

SciTech Connect

The inherently small system sizes involved imply that, in the absence of large applied fields designed to overwhelm them, fluctuations will play a major role in determining the response and functionality of nanoscale systems. Theoretical advances over the past two decades have provided fresh insight into fluctuations and their role at the nanoscale, even in the presence of arbitrarily large applied external fields. In contrast to traditional engineered systems, Nature s approach to nanotechnology is to embrace and to exploit fluctuations and noise to create adaptable, persistent, optimized functional architectures. We describe some of the mechanisms by which Nature exploits noise, with the goal of applying these lessons to engineered physical and chemical nanosystems. In particular, we emphasize the critical role of the tails of distributions of properties in both physical and biological nanosystems and their impact on system behavior.

Simpson, Michael L [ORNL; Cummings, Peter T [ORNL

2011-01-01

204

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

205

Thermal stabilization of uranium mill tailings  

Microsoft Academic Search

The treatment of uranium mill tailings by high-temperature sintering (>1050°C) has been investigated as a means of controlling the release of ²²²Rn and leachable contaminants. Thermal stabilization in laboratory trials at 1200°C reduced the radon emanation of various tailings by factors ranging from 37 to 1400 depending on the mineralogy of the tailings. The leachability of most contaminants (e.g., Al,

David R. Dreesen; Edward J. Cokal; Lawrence E. Wangen; Joel M. Williams; Edward F. Thode

1984-01-01

206

Active tails enhance arboreal acrobatics in geckos  

PubMed Central

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.

2008-01-01

207

Wean-Tail Log.xls  

Cancer.gov

A SP #: ________________ _ Investigator: _________________ WEAN / TAIL CLIP LOG Strain: ___________________ Room Number: ___________________ STRAIN CODE WEAN DATE # ? # ? COMMENTS WATER A OR B # CAGES DOB TAILCLIP DATE CAGE / LITTER

208

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

2008-03-18

209

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

210

Determinants  

NSDL National Science Digital Library

Created by Lewis Blake and Stephanie Fitchett of the Connected Curriculum Project, the purposes of this module are to explore the properties of determinants of matrices and to develop an important theoretical formula. This is part of a larger collection of material hosted by Duke University.

Blake, Lewis

211

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

212

Shake a Tail Feather: The Evolution of the Theropod Tail into a Stiff Aerodynamic Surface  

PubMed Central

Theropod dinosaurs show striking morphological and functional tail variation; e.g., a long, robust, basal theropod tail used for counterbalance, or a short, modern avian tail used as an aerodynamic surface. We used a quantitative morphological and functional analysis to reconstruct intervertebral joint stiffness in the tail along the theropod lineage to extant birds. This provides new details of the tail’s morphological transformation, and for the first time quantitatively evaluates its biomechanical consequences. We observe that both dorsoventral and lateral joint stiffness decreased along the non-avian theropod lineage (between nodes Theropoda and Paraves). Our results show how the tail structure of non-avian theropods was mechanically appropriate for holding itself up against gravity and maintaining passive balance. However, as dorsoventral and lateral joint stiffness decreased, the tail may have become more effective for dynamically maintaining balance. This supports our hypothesis of a reduction of dorsoventral and lateral joint stiffness in shorter tails. Along the avian theropod lineage (Avialae to crown group birds), dorsoventral and lateral joint stiffness increased overall, which appears to contradict our null expectation. We infer that this departure in joint stiffness is specific to the tail’s aerodynamic role and the functional constraints imposed by it. Increased dorsoventral and lateral joint stiffness may have facilitated a gradually improved capacity to lift, depress, and swing the tail. The associated morphological changes should have resulted in a tail capable of producing larger muscular forces to utilise larger lift forces in flight. Improved joint mobility in neornithine birds potentially permitted an increase in the range of lift force vector orientations, which might have improved flight proficiency and manoeuvrability. The tail morphology of modern birds with tail fanning capabilities originated in early ornithuromorph birds. Hence, these capabilities should have been present in the early Cretaceous, with incipient tail-fanning capacity in the earliest pygostylian birds. PMID:23690987

Pittman, Michael; Gatesy, Stephen M.; Upchurch, Paul; Goswami, Anjali; Hutchinson, John R.

2013-01-01

213

A Dog Tail for Utility Robots Exploring Affective Properties of Tail Movement  

E-print Network

A Dog Tail for Utility Robots Exploring Affective Properties of Tail Movement Ashish Singh, James E}@cs.umanitoba.ca Abstract. We present a dog-tail interface for utility robots, as a means of com- municating high-level robotic state through affect. This interface leverages peo- ple's general knowledge of dogs

214

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. PMID:19302717

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

2009-01-01

215

Human Sperm Tail Proteome Suggests New Endogenous Metabolic Pathways*  

PubMed Central

Proteomic studies are contributing greatly to our understanding of the sperm cell, and more detailed descriptions are expected to clarify additional cellular and molecular sperm attributes. The aim of this study was to characterize the subcellular proteome of the human sperm tail and, hopefully, identify less concentrated proteins (not found in whole cell proteome studies). Specifically, we were interested in characterizing the sperm metabolic proteome and gaining new insights into the sperm metabolism issue. Sperm were isolated from normozoospermic semen samples and depleted of any contaminating leukocytes. Tail fractions were obtained by means of sonication followed by sucrose-gradient ultracentrifugation, and their purity was confirmed via various techniques. Liquid chromatography and tandem mass spectrometry of isolated sperm tail peptides resulted in the identification of 1049 proteins, more than half of which had not been previously described in human sperm. The categorization of proteins according to their function revealed two main groups: proteins related to metabolism and energy production (26%), and proteins related to sperm tail structure and motility (11%). Interestingly, a great proportion of the metabolic proteome (24%) comprised enzymes involved in lipid metabolism, including enzymes for mitochondrial beta-oxidation. Unexpectedly, we also identified various peroxisomal proteins, some of which are known to be involved in the oxidation of very long chain fatty acids. Analysis of our data using Reactome suggests that both mitochondrial and peroxisomal pathways might indeed be active in sperm, and that the use of fatty acids as fuel might be more preponderant than previously thought. In addition, incubation of sperm with the fatty acid oxidation inhibitor etomoxir resulted in a significant decrease in sperm motility. Contradicting a common concept in the literature, we suggest that the male gamete might have the capacity to obtain energy from endogenous pools, and thus to adapt to putative exogenous fluctuations. PMID:23161514

Amaral, Alexandra; Castillo, Judit; Estanyol, Josep Maria; Ballescà, José Luís; Ramalho-Santos, João; Oliva, Rafael

2013-01-01

216

Unascertained measure assessment on environmental impact of tailings pond  

Microsoft Academic Search

This The index system of environmental impact assessment of tailings pond is hierarchal structure. As there is inherent uncertainty in determining the evaluation grade of low-level indicators and the relationship between the up-level and low-level indicators is non-linear, therefore, the evaluation model should have to deal with the uncertainty of information and achieve the non-linear conversion. As we can describe

Yanjun Pang; Wei Pan; Kaidi Liu

2010-01-01

217

Summary of the engineering assessment of inactive uranium mill tailings: Falls City site, Falls City, Texas  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevaluated the Falls City site in order to update the December 1977 engineering assessment of the problems resulting from the existence of radioactive uranum mill tailings at Falls City, Texas. 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 hydrolgy and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 2.5 million tons of tailings at the Falls City 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, to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the four options range from about $21,700,000 for stabilization in place, to about $35,100,000 for disposal at a distance of about 15 mi. Three principal alternatives for the reprocessing of the Falls City tailings were examined: heap leaching; treatment at an existing mill; reprocessing at a new conventional mill constructed for tailings reprocessing. The tailings piles are presently being rewashed for uranium recovery by Solution Engineering, Inc. The cost for further reprocessing would be about $250/lb of U/sub 3/O/sub 8/. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery does not appear to be economically attractive for the foreseeable future.

none,

1981-10-01

218

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

219

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

220

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

221

VARIATION IN THE SHARP-TAILED SPARROWS  

Microsoft Academic Search

In 1995, following Greenlaw (1993), the AOU split the Sharp-tailed Sparrow into two species, the Saltmarsh (Ammodramus caudacutus) and Nelson's (A. nelsoni) Sharp-tailed Sparrows. The former breeds in coastal saltmarshes of the central East Coast, the latter in the northern interior, around the southern coast of Hudson Bay, and along the northeastern seaboard. Both species winter along the southern Atlantic

STEVE N. G. HOWELL; DAVID A. SIBLEY

1998-01-01

222

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

2008-08-15

223

Supersonic aerodynamic characteristics of canard, tailless, and aft-tail configurations for 2 wing planforms  

NASA Technical Reports Server (NTRS)

Aerodynamic characteristics of canard, tailless, and aft tail configurations were compared in tests on a general research model (generic fuselage without canopy, inlets, or vertical tails) at Mach 1.60 and 2.00 in the Langley Unitary Plan Wind Tunnel. Two uncambered wing planforms (trapezoidal with 44 deg leading edge sweep and delta with 60 deg leading edge sweep) were tested for each configuration. The relative merits of the configurations were also determined theoretically, to evaluate the capabilities of a linear theory code for such analyses. The canard and aft tail configurations have similar measured values for lift curve slope, maximum lift drag ratio, and zero lift drag. The stability decrease as Mach number increases is greatest for the tailless configuration and least for the canard configuration. Because of very limited accuracy in predicting the aerodynamic parameter increments between configurations, the linear theory code is not adequate for determining the relative merits of canard, tailless, and aft tail configurations.

Covell, P. F.

1985-01-01

224

Arsenic mobility in soils impacted by tailings at Zimapán, México  

NASA Astrophysics Data System (ADS)

The Zimapán mining zone, in Central México is one of the worldwide sites known for As contamination. For more than 20 years and until recently, As-rich groundwater, mainly due to mineralization in a limestone aquifer, was an important source of As exposure to the inhabitants. In addition, decades of ore processing have produced hazardous wastes (tailings), many of them settled in the town outskirts. Although mineralogical and chemical differences exist among the various deposits; every one has high As contents (up to several thousands mg/kg) and other toxic elements that may be released to the nearby soils. To assess As mobility in soils impacted by tailings, total and sequential fractionation determinations were performed in 120 superficial and 40 cm depth samples collected at various distances near three of the impoundments. Higher total As concentrations were measured in the dry (up to 51,534 mg/kg) with respect to the rainy season (up to 23,570 mg/kg) indicating the occurrence of As wash off by rain. Although concentrations were lower in the deep regarding the superficial samples at most sites, As contents reached several thousands mg/kg at 40 cm depth indicating also its vertical transport that may reach the shallow aquifer. Sequential extractions showed differences between soils impacted by highly oxidized (red) tailings and low oxidized (gray) deposits. Most of the As occurs in the Fe-Mn oxides fraction (up to 92%) followed by the organic matter and sulfides fraction (up to 52 %) in soils close to red tailings, while organic matter and sulfide fraction contain most of the As (up to 95%) in soil samples close to low-oxidized deposits. Arsenic proportion in the residual fraction increased with distance from oxidized tailings. Low pH values (from 2.0 to 2.5) in superficial soils revealed the influence of acid mine drainage at distances up to 40 m from the red deposit. In contrast, the lowest pH was 7.1 in soils impacted by low-oxidized deposits, reflecting the limestone environment. Arsenic airborne transport was evidenced by the presence of a total As concentration of 30,780 mg/kg in soils collected at 120 m in front of the tailings crossing a ravine. Although sequential extraction showed that most of the As is present in relatively low-mobility fractions, total As concentrations indicate that tailings impoundments constitute another source of environmental As exposure.

Aurora Armienta, M.; Resendiz, Isabel; Múgica, Violeta; Cruz, Olivia; Aguayo, Alejandra; Ceniceros, Nora

2014-05-01

225

Lifting-surface-theory aspect-ratio corrections to the lift and hinge-moment parameters for full-span elevators on horizontal tail surfaces  

NASA Technical Reports Server (NTRS)

A limited number of lifting-surface-theory solutions for wings with chordwise loadings resulting from angle of attack, parabolic-ac camber, and flap deflection are now available. These solutions were studied with the purpose of determining methods of extrapolating the results in such a way that they could be used to determine lifting-surface-theory values of the aspect-ratio corrections to the lift and hinge-moment parameters for both angle-of-attack and flap-deflection-type loading that could be used to predict the characteristics of horizontal tail surfaces from section data with sufficient accuracy for engineering purposes. Such a method was devised for horizontal tail surfaces with full-span elevators. In spite of the fact that the theory involved is rather complex, the method is simple to apply and may be applied without any knowledge of lifting-surface theory. A comparison of experimental finite-span and section value and of the estimated values of the lift and hinge-moment parameters for three horizontal tail surfaces was made to provide an experimental verification of the method suggested. (author)

Swanson, Robert S; Crandall, Stewart M

1948-01-01

226

Notochord-derived hedgehog is essential for tail regeneration in Xenopus tadpole  

PubMed Central

Background Appendage regeneration in amphibians is regulated by the combinatorial actions of signaling molecules. The requirement of molecules secreted from specific tissues is reflected by the observation that the whole process of regeneration can be inhibited if a certain tissue is removed from the amputated stump. Interestingly, urodeles and anurans show different tissue dependencies during tail regeneration. The spinal cord is essential for tail regeneration in urodele but not in anuran larva, whereas the notochord but not the spinal cord is essential for tail regeneration in anuran tadpoles. Sonic hedgehog is one of the signaling molecules responsible for such phenomenon in axolotl, as hedgehog signaling is essential for overall tail regeneration and sonic hedgehog is exclusively expressed in the spinal cord. In order to know whether hedgehog signaling is involved in the molecular mechanism underlying the inconsistent tissue dependency for tail regeneration between anurans and urodeles, we investigated expression of hedgehog signal-related genes in the regenerating tail of Xenopus tadpole and examined the effect of the hedgehog signal inhibitor, cyclopamine, on the tail regeneration. Results In Xenopus, sonic hedgehog is expressed exclusively in the notochord but not in the spinal cord of the regenerate. Overall regeneration was severely impaired in cyclopamine-treated tadpoles. Notochord maturation in the regenerate, including cell alignment and vacuolation, and myofiber formation were inhibited. Proliferation of spinal cord cells in the neural ampulla and of mesenchymal cells was also impaired. Conclusion As in the axolotl, hedgehog signaling is required for multiple steps in tail regeneration in the Xenopus tadpole, although the location of the Shh source is quite different between the two species. This difference in Shh localization is the likely basis for the differing tissue requirement for tail regeneration between urodeles and anurans. PMID:24941877

2014-01-01

227

Parent Involvement  

E-print Network

To be successful, a 4-H program must have parent involvement. Although 4-H leaders and Extension agents may interest young people in becoming members, they need the parents' goodwill and support to keep them interested, enthusiastic and active. Here...

Howard, Jeff W.

2005-05-10

228

Assessment of computational prediction of tail buffeting  

NASA Technical Reports Server (NTRS)

Assessments of the viability of computational methods and the computer resource requirements for the prediction of tail buffeting are made. Issues involved in the use of Euler and Navier-Stokes equations in modeling vortex-dominated and buffet flows are discussed and the requirement for sufficient grid density to allow accurate, converged calculations is stressed. Areas in need of basic fluid dynamics research are highlighted: vorticity convection, vortex breakdown, dynamic turbulence modeling for free shear layers, unsteady flow separation for moderately swept, rounded leading-edge wings, vortex flows about wings at high subsonic speeds. An estimate of the computer run time for a buffeting response calculation for a full span F-15 aircraft indicates that an improvement in computer and/or algorithm efficiency of three orders of magnitude is needed to enable routine use of such methods. Attention is also drawn to significant uncertainties in the estimates, in particular with regard to nonlinearities contained within the modeling and the question of the repeatability or randomness of buffeting response.

Edwards, John W.

1990-01-01

229

Cross-tail current - Resonant orbits  

NASA Astrophysics Data System (ADS)

A technique to generate self-consistent 1D current sheets is described. Groups of monoenergetic protons were followed in a modified Harris magnetic field. This sample current sheet is characterized by resonant quasi-adiabatic orbits. The magnetic moment of a quasi-adiabatic ion which is injected from outside a current sheet changes substantially during the orbit but returns to almost its initial value by the time the ion leaves. Several ion and electron groups were combined to produce a plasma sheet in which the charged particles carry the currents needed to generate the magnetic field in which the orbits were traced. An electric field also is required to maintain charge neutrality. Three distinct orbit types, one involving untrapped ions and two composed of trapped ions, were identified. Limitations associated with the use of a 1D model also were investigated; it can provide a good physical picture of an important component of the cross-tail current, but cannot adequately describe any region of the magnetotail in which the principal current sheet is separated from the plasma sheet boundary layer by a nearly isotropic outer position of the central plasma sheet.

Kaufmann, Richard L.; Lu, Chen

1993-09-01

230

14 CFR 23.497 - Supplementary conditions for tail wheels.  

Code of Federal Regulations, 2014 CFR

...a tail wheel, bumper, or an energy absorption device is provided to show compliance...the tail wheel, bumper, or energy absorption device; and (2) The supporting...the tail wheel, bumper, or energy absorption device must be designed to...

2014-01-01

231

14 CFR 23.497 - Supplementary conditions for tail wheels.  

Code of Federal Regulations, 2012 CFR

...a tail wheel, bumper, or an energy absorption device is provided to show compliance...the tail wheel, bumper, or energy absorption device; and (2) The supporting...the tail wheel, bumper, or energy absorption device must be designed to...

2012-01-01

232

14 CFR 23.497 - Supplementary conditions for tail wheels.  

Code of Federal Regulations, 2011 CFR

...a tail wheel, bumper, or an energy absorption device is provided to show compliance...the tail wheel, bumper, or energy absorption device; and (2) The supporting...the tail wheel, bumper, or energy absorption device must be designed to...

2011-01-01

233

HABITAT SELECTION BY THE AMERICAN KESTREL (Falco sparverious) AND RED-TAILED HAWK (Buteojamaicensis) WINTERING IN  

Microsoft Academic Search

Habitat selection by the American Kestrel (Falco sparverius) and Red-tailed Hawk (Buteo jamaicensis) in Madison County, Kentucky, was determined for the winter of 1980-81. Results showed that there was significant non-random use of 6 habitat types (Kestrels: X 2 = 629.5, P  0.05, d.f. = 5; Red-tailed Hawks: X 2 = 124.8, P  0.05, d.f. = 5) with

234

A new approach to electromagnetic wave tails on a curved spacetime  

E-print Network

We present an alternative method for constructing the exact and approximate solutions of electromagnetic wave equations whose source terms are arbitrary order multipoles on a curved spacetime. The developed method is based on the higher-order Green's functions for wave equations which are defined as distributions that satisfy wave equations with the corresponding order covariant derivatives of the Dirac delta function as the source terms. The constructed solution is applied to the study of various geometric effects on the generation and propagation of electromagnetic wave tails to first order in the Riemann tensor. Generally the received radiation tail occurs after a time delay which represents geometrical backscattering by the central gravitational source. It is shown that the truly nonlocal wave-propagation correction (the tail term) takes a universal form which is independent of multipole order. In a particular case, if the radiation pulse is generated by the source during a finite time interval, the tail term after the primary pulse is entirely determined by the energy-momentum vector of the gravitational field source: the form of the tail term is independent of the multipole structure of the gravitational source. We apply the results to a compact binary system and conclude that under certain conditions the tail energy can be a noticeable fraction of the primary pulse energy. We argue that the wave tails should be carefully considered in energy calculations of such systems.

R. Mankin; T. Laas; R. Tammelo

2000-09-22

235

Flight investigation of the effect of tail boom strakes on helicopter directional control  

NASA Technical Reports Server (NTRS)

A joint U.S. Army/NASA flight investigation was conducted utilizing a single-rotor helicopter to determine the effectiveness of horizontally mounted tail boom strakes on directional controllability and tail rotor power during low-speed, crosswind operating conditions. Three configurations were investigated: (1) baseline (strakes off), (2) single strake (strake at upper shoulder on port side of boom), and (3) double strake (upper strake plus a lower strake on same side of boom). The strakes were employed as a means to separate airflow over the tail boom and change fuselage yawing moments in a direction to improve the yaw control margin and reduce tail rotor power. Crosswind data were obtained in 5-knot increments of airspeed from 0 to 35 knots and in 30 deg increments of wind azimuth from 0 deg to 330 deg. At the most critical wind azimuth and airspeed in terms of tail rotor power, the strakes improved the pedal margin by 6 percent of total travel and reduced tail rotor power required by 17 percent. The increase in yaw control and reduction in tail rotor power offered by the strakes can expand the helicopter operating envelope in terms of gross weight and altitude capability. The strakes did not affect the flying qualities of the vehicle at airspeeds between 35 and 100 knots.

Kelly, Henry L.; Crowell, Cynthia A.; Yenni, Kenneth R.; Lance, Michael B.

1993-01-01

236

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

Federal Register 2010, 2011, 2012, 2013, 2014

...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

237

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. PMID:19707550

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

2009-01-01

238

Diversity among the tailed-bacteriophages that infect the Enterobacteriaceae  

PubMed Central

Complete genome sequences have been determined for seventy-three tailed-phages that infect members of the bacterial Enterobacteriaceae family. Biological criteria such as genome size, gene organization and gene orientation were used to place these phages into categories. There are thirteen such categories, some of which are themselves extremely diverse. The relationships between and within these categories are discussed with an emphasis on the head assembly genes. Although some of them are clearly homologues, suggesting a very ancient origin, there is little evidence for exchange of individual head genes between these phage categories. More recent horizontal exchange of phage tail fiber and early proteins between the categories occurs, but is probably not extremely rapid. PMID:18550341

Casjens, Sherwood R.

2008-01-01

239

Charge compensation of head-to-head and tail-to-tail domain walls in barium titanate and its influence on conductivity  

SciTech Connect

The effect of the polarization charge compensation by ionic and electronic space charges on domain properties in ferroelectrics with semiconducting features is considered, in particular, the conductivity of head-to-head and tail-to-tail domain walls is studied. It is shown that the domain wall conductivity that is enhanced by electrons or holes depends on the configuration and the types of domains as well as on the energy levels and concentrations of the defects involved. Phase field simulation results are used to explain recent equivocal experimental results on conductivity of charged domain walls in different ferroelectrics.

Zuo, Yinan; Genenko, Yuri A.; Xu, Bai-Xiang, E-mail: xu@mfm.tu-darmstadt.de [Institute of Materials Science, Technische Universität Darmstadt, D-64287 Darmstadt (Germany)

2014-07-28

240

Genomic analyses of metal resistance genes in three plant growth promoting bacteria of legume plants in Northwest mine tailings, China.  

PubMed

To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria (PGPB). It shows that: Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF (Cation Diffusion Facilitator), HupE/UreJ and CHR (chromate ion transporter) family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative CopA/CueO system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while ZntA transporter, assisted with putative CzcD, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid (IAA) secretion, indicating a potential in-site phytoremediation usage in the mining tailing regions of China. PMID:25597676

Xie, Pin; Hao, Xiuli; Herzberg, Martin; Luo, Yantao; Nies, Dietrich H; Wei, Gehong

2015-01-01

241

Vibrations of the earth's magnetic tail  

NASA Technical Reports Server (NTRS)

The natural vibration period of the tail (regarded as bundle of magnetic line-of-force strings) and the characteristic time of recurrence of magnetospheric substorms are of the same order, suggesting the possibility of a relation between these phenomena. A model of the tail in the form of a plasma cylinder whose free boundary is immersed in the interplanetary plasma is examined. The nature of the natural oscillations of the tail excited by variations of the solar wind pressure is studied in this model. These vibrations have a total energy of approximately 10 to the 22nd power erg, which is sufficient to generate magnetospheric substorms.

Yershkovich, A. I.; Nusinov, A. A.

1974-01-01

242

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

243

Summary of the engineering assessment of inactive uranium mill tailings: Monument Valley site, Monument Valley, Arizona  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevaluated 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 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 1.1 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 to removal of the tailings to remote disposal sites and decontamination of the tailings site. 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 recovered would be more than $500/lb of U/sub 3/O/sub 8/ by heap leach or conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery is economically unattractive.

none,

1981-10-01

244

Engineering assessment of inactive uranium mill tailings: Slick Rock sites, Slick Rock, Colorado  

SciTech Connect

Ford, Bacon and Davis Utah, Inc., has reevaluated the Slick Rock sites in order to revise the October 1977 engineering radioactive uranium mill tailings at Slick Rock, Colorado. 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 387,000 tons of tailings at the Slick Rock sites constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The five alternative actions presented in this engineering assessment include millsite decontamination with the addition of 3 m of stabilization cover material, consolidation of the piles, and removal of the tailings to remote disposal sites and decontamination of the tailings sites. Cost estimates for the five options range from about $6,800,000 for stabilization in-place, to about $11,000,000 for disposal at a distance of about 6.5 mi. Three principal alternatives for the reprocessing of the Slick Rock 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 recovered would be over $800/lb of U/sub 3/O/sub 8/ whether by conventional or heap leach 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 at present, nor for the foreseeable future.

none,

1981-09-01

245

Engineering assessment of inactive uranium mill tailings: Mexican Hat Site, Mexican Hat, Utah  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevaluated the Mexican Hat site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Mexican Hat, Utah. 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 2.2 million tons of tailings at the Mexican Hat 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 to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the four options range from about $15,200,000 for stabilization in place, to about $45,500,000 for disposal at a distance of about 16 mi. Three principal alternatives for the reprocessing of the Mexican Hat 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 recovered would be about $115/lb of U/sub 3/O/sub 8/ whether by heap leach or conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Reprocessing the Mexican Hat tailings for uranium recovery is not economically attractive under present conditions.

none,

1981-09-01

246

Engineering assessment of inactive uranium mill tailings: Maybell Site, Maybell, Colorado  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevaluated the Maybell site in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Maybell, Colorado. 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 2.6 million dry tons of tailings at the Maybell site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The two alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to disposal of the tailings in a nearby open pit mine and decontamination of the tailings site (Option II). Cost estimates for the two options are about $11,700,000 for stabilization in-place and about $22,700,000 for disposal within a distance of 2 mi. Three principal alternatives for the reprocessing of the Maybell 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 $125 and $165/lb of U/sub 3/O/sub 8/ by heap leach and conventional plant processes, respectively. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery is not economically attractive at present.

none,

1981-09-01

247

Engineering assessment of inactive uranium mill tailings: Maybell Site, Maybell, Colorado. Summary  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevaluated the Maybell site in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Maybell, Colorado. 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 2.6 million dry tons of tailings at the Maybell site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The two alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to disposal of the tailings in a nearby open pit mine and decontamination of the tailings site (Option II). Cost estimates for the two options are about $11,700,000 for stabilization in-place and about $22,700,000 for disposal within a distance of 2 mi. Three principal alternatives for the reprocessing of the Maybell 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 $125 and $165/lb of U/sub 3/O/sub 8/ by heap leach and conventional plant processes, respectively. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery is not economically attractive at present.

none,

1981-09-01

248

A Christmas "E-Tail"  

NSDL National Science Digital Library

As the weather outside turns frightful, retail businesses with "e-tail" (electronic retail) Websites are hoping that consumers will turn to their home computers for their holiday shopping. A Forrester Research report estimates that seven million shoppers will spend close to $4 billion in online shopping, three times more than last year. However, this equals less than one percent of total holiday spending, estimated at $184 billion this holiday season. Most online retailers have increased the capacity and speed of their Websites in order to best serve holiday shoppers, hoping that this year's online shopping experiences will lead consumers to do a greater amount of next year's holiday shopping by way of the World Wide Web. While consumers are willing to try e-commerce sites, as many as 40 percent of experienced Internet users have found the process of online shopping confusing and complicated. This week's In the News examines the trend of online shopping with the following seven resources including news articles, advice, and related Websites.

Missner, Emily D.

249

Histochemical, Biochemical and Cell Biological aspects of tail regeneration in lizard, an amniote model for studies on tissue regeneration.  

PubMed

The present review summarizes biochemical, histochemical and immunocytochemical aspects of the process of tissue regeneration in lizards, non-mammalian amniotes with high regenerative power. The amputated tail initially mobilizes the glycogen and lipid reserves during wound healing. In the following stage of formation of the regenerative blastema tissue remodeling produces a typical embryonic tissue, initially increasing the amount of water and glycosaminoglycans such as jaluronate, which are later replaced by sulfated glycosaminoglycans and collagen during tail elongation. In blastematic and early differentiating stages the initial anaerobic metabolism utilizes glycolysis and hexose monophosphate pathways to sustain high RNA production and lipid catabolism for energy production. This stage, after formation of blood vessels, is replaced by the energy-efficient aerobic metabolism based on the Krebs' cycle that is needed for the differentiation and growth of the new tissues of the regenerating tail. Specific proteins of the cytoskeleton, extracellular matrix, cell junctions, transcriptional and growth factors are actively produced in the embryonic environment of early stages of regeneration and allow for cell movement, signaling and differentiation. During wound healing, the production of anti-microbial peptides in granulocytes is likely involved in limiting inflammation and stimulates tissue regeneration in the tail while the lasting inflammatory reaction of the limb and spinal cord limits their potential of regeneration. Activated hemopoiesis, circulating blood, endocrine glands, liver, kidney and spleen supply the regenerating tissues with metabolites and hormones but also with phagocytes and immuno-competent cells that can inhibit tissue regeneration after repetitive amputations that elicit chronic inflammation. The latter aspect shows how successful tissue regeneration in an amniote can be turned into scarring by the alteration of the initial microenvironment and inflammatory course, an inspiring model for understanding failure of tissue regeneration in higher vertebrates and humans. The participation of 5-Bromo-deoxyuridine (5BrdU) long retention cells, indicated as putative stem cells, for the following regeneration is analyzed and it shows that different tissue sites of the original tail contain putative stem cells that are likely activated from the wounding signal. In particular, the permanence of stem cells in the central canal of the spinal cord can explain the limited but important neurogenesis present in the caudal but also in the lumbar-thoracic spinal cord. In the latter, the limited number of glial and neurons regenerated is however sufficient to recover some limited hind limb movement after injury or spinal transection. Finally, the presence of stem cells in the spinal cord, in the regenerative blastema and skin allow to use these organs as a source of cells for studies on gene activation during cell differentiation in the new spinal cord, tail and in the epidermis. The above information form the basic knowledge for the future molecular studies on the specific gene activation capable to determine tail regeneration in lizards, and more in general genes involved in the reactivation of regeneration process in amniotes and humans. PMID:24387878

Alibardi, Lorenzo

2014-01-01

250

Vinculin Tail Dimerization and Paxillin Binding  

NASA Astrophysics Data System (ADS)

Vinculin is a highly conserved cytoskeletal protein that is essential for regulation of cell morphology and migration, and is a critical component of both cell-cell and cell-matrix complexes. The tail domain of vinculin (Vt) was crystallized as a homodimer and is believed to bind F-actin as a dimer. We have characterized Vt dimerization by Nuclear Magnetic Resonance (NMR) Spectroscopy and identified the dimer interface in solution by chemical shift perturbation. The Vt dimer interface in solution is similar to the crystallographic dimer interface. Interestingly, the Vt dimer interface determined by NMR partially overlaps the paxillin binding region previously defined coarsely by deletion mutagenesis and gel-blot assays. To further characterize the paxillin binding site in Vt and probe relationship between paxillin binding and dimerization, we conducted chemical shift perturbations experiments using a paxillin derived peptide, LD2. Our NMR experiments have confirmed that the paxillin binding site and the Vt dimerization site partially overlap, and we have further characterized both of these two binding interfaces. Information derived from these studies was used to identify mutations in Vt that selectively perturb paxillin binding and Vt self-association. These mutants are currently being characterized for their utility in structural and biological analyses to elucidate the role of paxillin binding and Vt dimerization in vinculin function.

Campbell, Sharon

2006-03-01

251

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

NASA Technical Reports Server (NTRS)

During MESSENGER's third flyby of Mercury, the magnetic field in the planet's magnetotail increased by factors of 2 to 3.5 over intervals of 2 to 3 min. Magnetospheric substorms at Earth are powered by similar tail loading, but the amplitude is approx.10 times less and typical durations are approx.1 hour. The extreme tail loading observed at Mercury implies that the relative intensity of sub storms 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 substorm timescale. 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., Jr.; Nittler, Larry R.; Raines, Jim M.; Sarantos, Menelaos; Schriver, David; Solomon, Sean C.; Starr, Richard D.; Travnicek, Pavel M.; Zurbuchen, Thomas H.

2010-01-01

252

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

253

Engineering assessment of inactive uranium mill tailings, Green River Site, Green River, Utah  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevaluated the Green River site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Green River, Utah. 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 evaluation and costing of alternative remedial actions. Radon gas released from the 123,000 tons of tailings at the Green River site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors.

none,

1981-08-01

254

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

255

The Relationship between Self-Determination and Quality of Life among Individuals with Disabilities Involved with a Center for Independent Living  

ERIC Educational Resources Information Center

Individuals with disabilities have historically been compromised in their ability to assert independence with respect to concepts of independent living and self-determination. In turn this may potentially impact an individual's overall quality of life. Community integration and availability of a full quality of life and to be self-determined has…

Bekemeier, Karsten

2009-01-01

256

A Field and Modeling Study of Windblown Particles from a Uranium Mill Tailings Pile  

SciTech Connect

An extensive field study whose primary objective was to obtain knowledge and understanding of the nature and quantity of windblown particles from uranium mill tailings piles was conducted in the Ambrosia Lake District of New Mexico. The following major field tasks were undertaken: determination of physical, chemical, and radioactivity characteristics of mill tailings particles; an investigation of the nature and quantity of tailings particles in soil in the vicinity of tailings piles; and the determination of the nature and flux of particles being transported by wind as a function of wind speed and height. Results of the field study are presented. Particle size distributions and associated radioactivity were measured. Radioactivity relationships showed uranium daughters in mill tailings to be in essential radioactive equilibrium for the carbonate leach process but thorium-230 tends to be leached into the slurry water for the acid process mill tailings. One objective of the study was to relate windblown particle concentrations, fluxes, and particle sizes to wind speed. Hundreds of samples were taken and analyses were performed, but relationships between wind speed, airborne particle sizes and concentrations were found to be vague and inconclusive. A resuspension, deposition, and transport model was developed and applied using site meteorology. Ground deposition patterns predicted were similar to those found.

Schwendiman, L. C.; Sehmel, G. A.; Horst, T. W.; Thomas, C. W.; Perkins, R. W.

1980-06-01

257

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. PMID:12028763

Evans, Matthew R; Rosén, Mikael; Park, Kirsty J; Hedenström, Anders

2002-01-01

258

The Distant Sodium Tail of Mercury  

NASA Technical Reports Server (NTRS)

Models of the sodium atmosphere of Mercury predict the possible existence of a cornet-like sodium tail. Detection and mapping of the predicted sodium tail would provide quantitative data on the energy of the process that produces sodium atoms from the planetary surface. Previous efforts to detect the sodium tail by means of observations done during daylight hours have been only partially successful because scattered sunlight obscured the weak sodium emissions in the tail. However, at greatest eastern elongation around the March equinox in the northern hemisphere, Mercury can be seen as an evening star in astronomical twilight. At this time, the intensity of scattered sunlight is low enough that sodium emissions as low as 500 Rayleighs can be detected. Additional information is contained in the original extended abstract.

Potter, A. E.; Killen, R. M.; Morgan, T. H.

2001-01-01

259

Physical space and long-tail markets  

NASA Astrophysics Data System (ADS)

The Internet is known to have had a powerful impact on on-line retailer strategies in markets characterised by long-tail distribution of sales [C. Anderson, Long Tail: Why the Future of Business is Selling Less of More, Hyperion, New York, 2006]. Such retailers can exploit the long tail of the market, since they are effectively without physical limit on the number of choices on offer. Here we examine two extensions of this phenomenon. First, we introduce turnover into the long-tail distribution of sales. Although over any given period such as a week or a month, the distribution is right-skewed and often power law distributed, over time there is considerable turnover in the rankings of sales of individual products. Second, we establish some initial results on the implications for shelf-space and physical retailers in such markets.

Bentley, R. Alexander; Madsen, Mark E.; Ormerod, Paul

2009-03-01

260

Effects of Tail on Spinning Aircraft Model  

NASA Astrophysics Data System (ADS)

The experiment on aircraft spin phenomena was conducted at the low speed wind tunnel of Nagoya University with its exit test section inclined vertically. The model used in this experiment consists of three parts: a main wing, a fuselage, and a tail. Due to the stability effect of the tail, rotation of the model is decreased at low angles of attack, while it is increased at high angles of attack. As a result of pressure measurements, the horizontal tail wing was found to be the cause of this phenomenon. More specifically, a vortex is created from the leading edge of the windward horizontal tail wing, so that negative pressure regions appear on the windward horizontal wing and the vertical wing.

Yamada, Takafumi; Horichi, Takao; Nakamura, Yoshiaki

261

Type 1 Tails: Solar Wind Interactions  

NASA Technical Reports Server (NTRS)

The ionization of the gas emitted by a comet is discussed along with the formation of a visible tail, and the bow shock front upstream toward the sun. Questions that a cometary probe can answer are listed.

Biermann, L.

1972-01-01

262

Effects of tail docking and docking length on neuroanatomical changes in healed tail tips of pigs.  

PubMed

In pig production, piglets are tail docked at birth in order to prevent tail biting later in life. In order to examine the effects of tail docking and docking length on the formation of neuromas, we used 65 pigs and the following four treatments: intact tails (n=18); leaving 75% (n=17); leaving 50% (n=19); or leaving 25% (n=11) of the tail length on the pigs. The piglets were docked between day 2 and 4 after birth using a gas-heated apparatus, and were kept under conventional conditions until slaughter at 22 weeks of age, where tails were removed and examined macroscopically and histologically. The tail lengths and diameters differed at slaughter (lengths: 30.6±0.6; 24.9±0.4; 19.8±0.6; 8.7±0.6 cm; P<0.001; tail diameter: 0.5±0.03; 0.8±0.02; 1.0±0.03; 1.4±0.04 cm; P<0.001, respectively). Docking resulted in a higher proportion of tails with neuromas (64 v. 0%; P<0.001), number of neuromas per tail (1.0±0.2 v. 0; P<0.001) and size of neuromas (1023±592 v. 0 ?m; P<0.001). The results show that tail docking piglets using hot-iron cautery causes formation of neuromas in the outermost part of the tail tip. The presence of neuromas might lead to altered nociceptive thresholds, which need to be confirmed in future studies. PMID:25482535

Herskin, M S; Thodberg, K; Jensen, H E

2015-04-01

263

TIDAL TAILS OF MINOR MERGERS. II. COMPARING STAR FORMATION IN THE TIDAL TAILS OF NGC 2782  

SciTech Connect

The peculiar spiral NGC 2782 is the result of a minor merger with a mass ratio {approx}4: 1 occurring {approx}200 Myr ago. This merger produced a molecular and H I-rich, optically bright eastern tail and an H I-rich, optically faint western tail. Non-detection of CO in the western tail by Braine et al. suggested that star formation had not yet begun. However, deep UBVR and H{alpha} narrowband images show evidence of recent star formation in the western tail, though it lacks massive star clusters and cluster complexes. Using Herschel PACS spectroscopy, we discover 158 {mu}m [C II] emission at the location of the three most luminous H{alpha} sources in the eastern tail, but not at the location of the even brighter H{alpha} source in the western tail. The western tail is found to have a normal star formation efficiency (SFE), but the eastern tail has a low SFE. The lack of CO and [C II] emission suggests that the western tail H II region may have a low carbon abundance and be undergoing its first star formation. The western tail is more efficient at forming stars, but lacks massive clusters. We propose that the low SFE in the eastern tail may be due to its formation as a splash region where gas heating is important even though it has sufficient molecular and neutral gas to make massive star clusters. The western tail, which has lower gas surface density and does not form high-mass star clusters, is a tidally formed region where gravitational compression likely enhances star formation.

Knierman, Karen A.; Scowen, Paul; Veach, Todd; Groppi, Christopher [School of Earth and Space Exploration, Arizona State University, 550 E. Tyler Mall, Room PSF-686 (P.O. Box 871404), Tempe, AZ 85287-1404 (United States); Mullan, Brendan; Charlton, Jane [Department of Astronomy and Astrophysics, Penn State University, 525 Davey Lab, University Park, PA (United States); Konstantopoulos, Iraklis [Australian Astronomical Observatory, P.O. Box 915, North Ryde NSW 1670 (Australia); Knezek, Patricia M., E-mail: karen.knierman@asu.edu, E-mail: paul.scowen@asu.edu, E-mail: tveach@asu.edu, E-mail: cgroppi@asu.edu, E-mail: mullan@astro.psu.edu, E-mail: iraklis@aao.gov.au, E-mail: pknezek@noao.edu [WIYN Consortium, Inc., 950 N. Cherry Avenue, Tucson, AZ 85719 (United States)

2013-09-10

264

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

265

Lizard tail regeneration: regulation of two distinct cartilage regions by Indian hedgehog.  

PubMed

Lizards capable of caudal autotomy exhibit the remarkable ability to "drop" and then regenerate their tails. However, the regenerated lizard tail (RLT) is known as an "imperfect replicate" due to several key anatomical differences compared to the original tail. Most striking of these "imperfections" concerns the skeleton; instead of the vertebrae of the original tail, the skeleton of the RLT takes the form of an unsegmented cartilage tube (CT). Here we have performed the first detailed staging of skeletal development of the RLT CT, identifying two distinct mineralization events. CTs isolated from RLTs of various ages were analyzed by micro-computed tomography to characterize mineralization, and to correlate skeletal development with expression of endochondral ossification markers evaluated by histology and immunohistochemistry. During early tail regeneration, shortly after CT formation, the extreme proximal CT in direct contact with the most terminal vertebra of the original tail develops a growth plate-like region that undergoes endochondral ossification. Proximal CT chondrocytes enlarge, express hypertrophic markers, including Indian hedgehog (Ihh), apoptose, and are replaced by bone. During later stages of tail regeneration, the distal CT mineralizes without endochondral ossification. The sub-perichondrium of the distal CT expresses Ihh, and the perichondrium directly calcifies without cartilage growth plate formation. The calcified CT perichondrium also contains a population of stem/progenitor cells that forms new cartilage in response to TGF-? stimulation. Treatment with the Ihh inhibitor cyclopamine inhibited both proximal CT ossification and distal CT calcification. Thus, while the two mineralization events are spatially, temporally, and mechanistically very different, they both involve Ihh. Taken together, these results suggest that Ihh regulates CT mineralization during two distinct stages of lizard tail regeneration. PMID:25596336

Lozito, Thomas P; Tuan, Rocky S

2015-03-15

266

Orexigenic response to tail pinch: role of brain NPY1 and corticotropin releasing factor receptors  

PubMed Central

Tail pinch stimulates food intake in rats. We investigated brain mechanisms of this response and the influence of repeated exposure. Sprague-Dawley rats received acute (5 min) or repeated (5 min/day for 14 days) tail pinch using a padded clip. Acute tail pinch increased 5-min food intake compared with control (0.92 ± 0.2 vs. 0.03 ± 0.01 g, P < 0.01). This response was inhibited by 76% by intracerebroventricular injection of BIBP-3226, a neuropeptide Y1 (NPY1) receptor antagonist, increased by 48% by astressin-B, a corticotropin-releasing factor (CRF) receptor antagonist, and not modified by S-406-028, a somatostatin subtype 2 antagonist. After the 5-min tail pinch without food, blood glucose rose by 21% (P < 0.01) while changes in plasma acyl ghrelin (+41%) and adrenocorticotropic hormone (+37%) were not significant. Two tail pinches (45 min apart) activate pontine and hindbrain catecholaminergic and hypothalamic paraventricular CRF neurons. After 14 days of repeated tail pinch, the 5-min orexigenic response was not significantly different from days 2 to 11 but reduced by 50% thereafter (P < 0.001). Simultaneously, the 5-min fecal pellet output increased during the last 5 days compared with the first 5 days (+58%, P < 0.05). At day 14, the body weight gain was reduced by 22%, with a 99% inhibition of fat gain and a 25% reduction in lean mass (P < 0.05). The orexigenic response to acute 5-min tail pinch is likely to involve the activation of brain NPY1 signaling, whereas that of CRF tends to dampen the acute response and may contribute to increased defecation and decreased body weight gain induced by repeated tail pinch. PMID:24338440

Goebel-Stengel, Miriam; Stengel, Andreas; Wang, Lixin

2013-01-01

267

Immunolocalization of FGF1 and FGF2 in the regenerating tail of the lizard Lampropholis guichenoti: implications for FGFs as trophic factors in lizard tail regeneration.  

PubMed

A role for fibroblast growth factors in stimulating limb and tail regeneration in amphibians has been shown; however, it is unknown whether these growth factors are also involved in the regeneration of the tail of lizard, an amniote model for studies on tissue regeneration. The presence of fibroblast growth factor-1 (FGF1) and -2 (FGF2) in the regenerating tail of the lizard Lampropholis guichenoti has been studied using immunofluorescence labeling. The study reveals that FGF2 is mainly localized in the wound and scaling epidermis, in differentiating muscles, in spinal ganglia, regenerating nerves and spinal cord. FGF1 is also present in the wound and differentiating epidermis, but is detectable at lower levels in the regenerating muscles and spinal cord. FGF1 is present in blastema cells, while FGF2 labeling is relatively low in these cells. Fibroblasts of the forming dermis are rich in FGF1 but not in FGF2. Developing blood vessels label for both FGF1 and FGF2 while the cartilaginous, bone and fat tissues are poorly labeled or unlabeled for FGFs. The present study suggests that most FGFs in the regenerating tail are located in the nervous system, in the epidermis and muscles, and these tissues most likely require these growth factors for their differentiation and growth. The present study suggests that FGFs produced in the regenerating epidermis, spinal cord and nerves can stimulate tail regeneration in lizards. PMID:19589562

Alibardi, Lorenzo; Lovicu, Frank J

2010-09-01

268

Confidence intervals for the tail index  

Microsoft Academic Search

One of the best-known estimators for the tail index of a heavy-tailed distribution is the Hill estimator. In this paper, confidence intervals based on the asymptotic normal approximation of the Hill estimator are studied. The coverage accuracy is evaluated and the theoretical optimal choice of the sample fraction for the one-sided confidence interval is given. One surprising finding is that

Shihong Cheng; Liang Peng

2001-01-01

269

Anomalously small wave tails in higher dimensions  

E-print Network

We consider the late-time tails of spherical waves propagating on even-dimensional Minkowski spacetime under the influence of a long range radial potential. We show that in six and higher even dimensions there exist exceptional potentials for which the tail has an anomalously small amplitude and fast decay. Along the way we clarify and amend some confounding arguments and statements in the literature of the subject.

Piotr Bizo?; Tadeusz Chmaj; Andrzej Rostworowski

2007-08-13

270

Autoclaved brick from low-silicon tailings  

Microsoft Academic Search

The load-bearing brick is made from low-silicon tailings by pressing and autoclaving process, in the presence of alkali-activated slag\\/fly ash cementing material (AAFSC). Tailings accounts for 83% of the total mass of the brick. The compressive strength of the brick is up to 16.1MPa, bending strength 3.8MPa, and with low drying shrinkage and good freeze–thaw resistance. Some factors influencing the

Feng-qing Zhao; Jing Zhao; Hong-jie Liu

2009-01-01

271

Environmental Assessment of remedial action at the Ambrosia Lake uranium mill tailings site, Ambrosia Lake, New Mexico  

SciTech Connect

This document assesses and compares the environmental impacts of various alternatives for remedial action at the Ambrosia Lake uranium mill tailings site located near Ambrosia Lake, New Mexico. The designated site covers 196 acres and contains 111 acres of tailings and some of the original mill structures. The Uranium Mill Tailings Radiation Control Act (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 properties off the site. The US Environmental Protection Agency promulgated standards for th remedial action (40 CFR Part 192). Remedial action must be performed in accordance with these standards and with the concurrence of the Nuclear Regulatory Commission. The proposed action is to stabilize the tailings at their present location by consolidating the tailings and associated contaminated materials into a recontoured pile. A radon barrier would be constructed over the pile and various erosion protection measures would be taken to assure the long-term stability of the pile. Another alternative which would involve moving the tailings to a new location is also assessed in this document. This alternative would generally involve greater short-term impacts and costs but would result in stabilization of the tailings at an undeveloped location. The no action alternative is also assessed in this document.

Not Available

1987-06-01

272

The Sodium Tail of the Moon  

NASA Technical Reports Server (NTRS)

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 solar radiation pressure that drives them into the anti-solar direction forming a comet-like tail. During new Moon time, the geometry of the Sun, Moon and Earth is such that the anti-sunward sodium flux is perturbed by the terrestrial gravitational field resulting in its focusing into a dense core that extends beyond the Earth. An all-sky camera situated at the El Leoncito Observatory (CASLEO) in Argentina has been successfully imaging this tail through a sodium filter at each lunation since April 2006. This paper reports on the results of the brightness of the lunar sodium tail spanning 31 lunations between April 2006 and September 2008. Brightness variability trends are compared with both sporadic and shower meteor activity, solar wind proton energy flux and solar near ultra violet (NUV) patterns for possible correlations. Results suggest minimal variability in the brightness of the observed lunar sodium tail, generally uncorrelated with any single source, yet consistent with a multi-year period of minimal solar activity and non-intense meteoric fluxes.

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

2009-01-01

273

Snapshot of haloarchaeal tailed virus genomes  

PubMed Central

The complete genome sequences of archaeal tailed viruses are currently highly underrepresented in sequence databases. Here, we report the genomic sequences of 10 new tailed viruses infecting different haloarchaeal hosts. Among these, only two viral genomes are closely related to each other and to previously described haloviruses HF1 and HF2. The approximately 760 kb of new genomic sequences in total shows no matches to CRISPR/Cas spacer sequences in haloarchaeal host genomes. Despite their high divergence, we were able to identify virion structural and assembly genes as well as genes coding for DNA and RNA metabolic functions. Interestingly, we identified many genes and genomic features that are shared with tailed bacteriophages, consistent with the hypothesis that haloarchaeal and bacterial tailed viruses share common ancestry, and that a viral lineage containing archaeal viruses, bacteriophages and eukaryotic viruses predates the division of the three major domains of non-viral life. However, as in tailed viruses in general and in haloarchaeal tailed viruses in particular, there are still a considerable number of predicted genes of unknown function. PMID:23470522

Sen?ilo, Ana; Jacobs-Sera, Deborah; Russell, Daniel A.; Ko, Ching-Chung; Bowman, Charles A.; Atanasova, Nina S.; Österlund, Eija; Oksanen, Hanna M.; Bamford, Dennis H.; Hatfull, Graham F.; Roine, Elina; Hendrix, Roger W.

2013-01-01

274

The sodium tail of the Moon  

NASA Astrophysics Data System (ADS)

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 solar radiation pressure that drives them into the anti-solar direction forming a comet-like tail. During new Moon time, the geometry of the Sun, Moon and Earth is such that the anti-sunward sodium flux is perturbed by the terrestrial gravitational field resulting in its focusing into a dense core that extends beyond the Earth. An all-sky camera situated at the El Leoncito Observatory (CASLEO) in Argentina has been successfully imaging this tail through a sodium filter at each lunation since April 2006. This paper reports on the results of the brightness of the lunar sodium tail spanning 31 lunations between April 2006 and September 2008. Brightness variability trends are compared with both sporadic and shower meteor activity, solar wind proton energy flux and solar near ultra violet (NUV) patterns for possible correlations. Results suggest minimal variability in the brightness of the observed lunar sodium tail, generally uncorrelated with any single source, yet consistent with a multi-year period of minimal solar activity and non-intense meteoric fluxes.

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

2009-12-01

275

Volume III, Chapter 13 Columbian White-tailed Deer  

E-print Network

-tailed Deer (Odocoileus virginianus leucurus) ........................... 13-1 13.1 Introduction virginianus leucurus) 13.1 Introduction The Columbian white-tailed deer (Odocoileus virginianus leucurus............................................................................. 13-20 #12;COLUMBIAN WHITE-TAILED DEER III, 13-1 May 2004 13.0 Columbian White-tailed Deer (Odocoileus

276

Effects of White-Tailed Deer on Populations of an Understory Forb in Fragmented Deciduous Forests  

Microsoft Academic Search

The effects of grazing by white-tailed deer ( Odocoileus virginianus ) on populations of Trillium spp. were examined in remnant, old-growth patches of the highly fragmented Big Woods forest ecosystem in south- eastern Minnesota. We conducted three separate studies involving an exclosure experiment, transplant exper- iments, and comparisons of Trillium populations among study sites. The highest grazing intensity was ob-

David J. Augustine; Lee E. Frelich

1998-01-01

277

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

278

Establishment and Growth of Two Willow Species in a Riparian Zone Impacted by Mine Tailings  

Microsoft Academic Search

A fi eld study was initiated to determine survival, growth characteristics, and metal uptake of two montane riparian willow species, Geyer (Salix geyeriana Andersson) and mountain (S. monticola Bebb) willow, grown in amended fl uvial mine tailing deposits. Revegetation was done with staked and previously rooted cuttings to determine if planting method had an eff ect on successful establishment of

Melody M. Bourret; Joe E. Brummer; Wayne C. Leininger

2009-01-01

279

Effect of tail size reductions on longitudinal aerodynamic characteristics of a three surface F-15 model with nonaxisymmetric nozzles  

NASA Technical Reports Server (NTRS)

An investigation was conducted in the Langley 16-Foot Transonic Tunnel to determine the effects of horizontal and vertical tail size reductions on the longitudinal aerodynamic characteristics of a modified F-15 model with canards and 2-D convergent-divergent nozzles. Quantifying the drag decrease at low angles of attack produced by tail size reductions was the primary focus. The model was tested at Mach numbers of 0.40, 0.90, and 1.20 over an angle of attack of -2 degree to 10 degree. The nozzle exhaust flow was simulated using high pressure air at nozzle pressure ratios varying from 1.0 (jet off) to 7.5. Data were obtained on the baseline configuration with and without tails as well as with reduced horizontal and/or vertical tail sizes that were 75, 50, and 25 percent of the baseline tail areas.

Frassinelli, Mark C.; Carson, George T., Jr.

1990-01-01

280

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

281

Signals of Ezh2, Src, and Akt Involve in Myostatin-Pax7 Pathways Regulating the Myogenic Fate Determination during the Sheep Myoblast Proliferation and Differentiation  

PubMed Central

Myostatin and Pax7 have been well documented individually, however, the mechanism by which Myostatin regulates Pax7 is seldom reported. Here, based on muscle transcriptome analysis in Texel (Myostatin mutant) and Ujumqin (wild type) sheep across the five fetal stages, we constructed and examined the Myostatin-Pax7 pathways in muscle. Then we validated the signals by RNAi in the proliferating and differentiating sheep myoblasts in vitro at mRNA, protein, and cell morphological levels. We reveal that Myostatin signals to Pax7 at least through Ezh2, Src, and Akt during the sheep myoblast proliferation and differentiation. Other signals such as p38MAPK, mTOR, Erk1/2, Wnt, Bmp2, Smad, Tgfb1, and p21 are most probably involved in the Myostatin-affected myogenic events. Myostatin knockdown significantly reduces the counts of nucleus and myotube, but not the fusion index of myoblasts during cell differentiation. In addition, findings also indicate that Myostatin is required for normal myogenic differentiation of the sheep myoblasts, which is different from the C2C12 myoblasts. We expand the regulatory network of Myostatin-Pax7 pathways and first illustrate that Myostatin as a global regulator participates in the epigenetic events involved in myogenesis, which contributes to understand the molecular mechanism of Myostatin in regulation of myogenesis. PMID:25811841

Li, Li; Liu, Ruizao; Zhang, Li; Zhao, Fuping; Lu, Jian; Zhang, Xiaoning; Du, Lixin

2015-01-01

282

Surface Plasmon Resonance Detection and Multispot Sensing for Direct Monitoring of Interactions Involving Low-Molecular-Weight Analytes and for Determination of Low Affinities  

Microsoft Academic Search

Surface plasmon resonance detection allows direct observation of molecular interactions between an analyte in solution and its immobilized binding partner. The use of simultaneous monitoring of interaction events on multiple sensing surfaces, with varying amounts of immobilized receptor, for detection of low-molecular-weight analytes and for determination of low affinities was investigated. Using multispot sensing and BIAcore 2000 instrumentation, analytes as

R. Karlsson; R. Stahlberg

1995-01-01

283

Research investigation of helicopter main rotor/tail rotor interaction noise  

NASA Technical Reports Server (NTRS)

Acoustic measurements were obtained in a Langley 14 x 22 foot Subsonic Wind Tunnel to study the aeroacoustic interaction of 1/5th scale main rotor, tail rotor, and fuselage models. An extensive aeroacoustic data base was acquired for main rotor, tail rotor, fuselage aerodynamic interaction for moderate forward speed flight conditions. The details of the rotor models, experimental design and procedure, aerodynamic and acoustic data acquisition and reduction are presented. The model was initially operated in trim for selected fuselage angle of attack, main rotor tip-path-plane angle, and main rotor thrust combinations. The effects of repositioning the tail rotor in the main rotor wake and the corresponding tail rotor countertorque requirements were determined. Each rotor was subsequently tested in isolation at the thrust and angle of attack combinations for trim. The acoustic data indicated that the noise was primarily dominated by the main rotor, especially for moderate speed main rotor blade-vortex interaction conditions. The tail rotor noise increased when the main rotor was removed indicating that tail rotor inflow was improved with the main rotor present.

Fitzgerald, J.; Kohlhepp, F.

1988-01-01

284

Spatial Characteristics of the Unsteady Differential Pressures on 16 percent F/A-18 Vertical Tails  

NASA Technical Reports Server (NTRS)

Buffeting is an aeroelastic phenomenon which plagues high performance aircraft at high angles of attack. For the F/A-18 at high angles of attack, vortices emanating from wing/fuselage leading edge extensions burst, immersing the vertical tails in their turbulent wake. The resulting buffeting of the vertical tails is a concern from fatigue and inspection points of view. Previous flight and wind-tunnel investigations to determine the buffet loads on the tail did not provide a complete description of the spatial characteristics of the unsteady differential pressures. Consequently, the unsteady differential pressures were considered to be fully correlated in the analyses of buffet and buffeting. The use of fully correlated pressures in estimating the generalized aerodynamic forces for the analysis of buffeting yielded responses that exceeded those measured in flight and in the wind tunnel. To learn more about the spatial characteristics of the unsteady differential pressures, an available 16%, sting-mounted, F-18 wind-tunnel model was modified and tested in the Transonic Dynamics Tunnel (TDT) at the NASA Langley Research Center as part of the ACROBAT (Actively Controlled Response Of Buffet-Affected Tails) program. Surface pressures were measured at high angles of attack on flexible and rigid tails. Cross-correlation and cross-spectral analyses of the pressure time histories indicate that the unsteady differential pressures are not fully correlated. In fact, the unsteady differential pressure resemble a wave that travels along the tail. At constant angle of attack, the pressure correlation varies with flight speed.

Moses, Robert W.; Ashley, Holt

1998-01-01

285

Wind-tunnel Investigation of the Contribution of a Vertical Tail to the Directional Stability of a Fighter-type Airplane  

NASA Technical Reports Server (NTRS)

Contributions of vertical tail and fuselage to directional stability are determined from pressure distributions measured over wide ranges of angle of attack and angle of yaw with stabilizer in each of three vertical positions, with stabilizer removed and with both stabilizer and vertical tail removed. Results point out inadequacies of current design methods and show that more accurate methods must treat separately contributions of vertical tail, fuselage area above stabilizer, and fuselage area below stabilizer.

Marino, Alfred A; Mastrocola, N

1952-01-01

286

Molecular detection of Babesia bovis and Babesia bigemina in white-tailed deer ( Odocoileus virginianus) from Tom Green County in central Texas  

Microsoft Academic Search

Serologic and molecular evidence suggest that white-tailed deer in South Texas and North Mexico carry the agents of bovine babesiosis, Babesia bovis and Babesia bigemina. To determine if white-tailed deer in central Texas, which is outside the known occurrence of the vector tick at this time, harbor these parasites, blood samples from free-ranging and captive white-tailed deer (Odocoileus virginianus) in

Patricia J. Holman; Juliette E. Carroll; Roberta Pugh; Donald S. Davis

2011-01-01

287

Scorpion sheds 'tail' to escape: consequences and implications of autotomy in scorpions (Buthidae: Ananteris).  

PubMed

Autotomy, the voluntary shedding or detachment of a body part at a determined cleavage plane, is a common anti-predation defense mechanism in several animal taxa, including arthropods. Among arachnids, autotomy has been observed in harvestmen, mites, and spiders, always involving the loss of legs. Autotomy of the opisthosoma (abdomen) was recently reported in a single species of the Neotropical buthid scorpion genus Ananteris Thorell, 1891, but few details were revealed. Based on observations in the field and laboratory, examination of material in museum collections, and scanning electron microscopy, we document autotomy of the metasoma (the hind part of the opisthosoma, or 'tail') in fourteen species of Ananteris. Autotomy is more common in males than females, and has not been observed in juveniles. When the scorpion is held by the metasoma, it is voluntarily severed at the joints between metasomal segments I and II, II and III, or III and IV, allowing the scorpion to escape. After detachment, the severed metasoma moves (twitches) automatically, much like the severed tail of a lizard or the severed leg of a spider, and reacts to contact, even attempting to sting. The severed surface heals rapidly, scar tissue forming in five days. The lost metasomal segments and telson cannot be regenerated. Autotomy of the metasoma and telson results in permanent loss of the posterior part of the scorpion's digestive system (the anus is situated posteriorly on metasomal segment V) and the ability to inject venom by stinging. After autotomy, scorpions do not defecate and can only capture small prey items. However, males can survive and mate successfully for up to eight months in the laboratory. In spite of diminished predation ability after autotomy, survival allows males to reproduce. Autotomy in Ananteris therefore appears to be an effective, adaptive, anti-predation escape mechanism. PMID:25629529

Mattoni, Camilo I; García-Hernández, Solimary; Botero-Trujillo, Ricardo; Ochoa, José A; Ojanguren-Affilastro, Andrés A; Pinto-da-Rocha, Ricardo; Prendini, Lorenzo

2015-01-01

288

Scorpion Sheds ‘Tail’ to Escape: Consequences and Implications of Autotomy in Scorpions (Buthidae: Ananteris)  

PubMed Central

Autotomy, the voluntary shedding or detachment of a body part at a determined cleavage plane, is a common anti-predation defense mechanism in several animal taxa, including arthropods. Among arachnids, autotomy has been observed in harvestmen, mites, and spiders, always involving the loss of legs. Autotomy of the opisthosoma (abdomen) was recently reported in a single species of the Neotropical buthid scorpion genus Ananteris Thorell, 1891, but few details were revealed. Based on observations in the field and laboratory, examination of material in museum collections, and scanning electron microscopy, we document autotomy of the metasoma (the hind part of the opisthosoma, or ‘tail’) in fourteen species of Ananteris. Autotomy is more common in males than females, and has not been observed in juveniles. When the scorpion is held by the metasoma, it is voluntarily severed at the joints between metasomal segments I and II, II and III, or III and IV, allowing the scorpion to escape. After detachment, the severed metasoma moves (twitches) automatically, much like the severed tail of a lizard or the severed leg of a spider, and reacts to contact, even attempting to sting. The severed surface heals rapidly, scar tissue forming in five days. The lost metasomal segments and telson cannot be regenerated. Autotomy of the metasoma and telson results in permanent loss of the posterior part of the scorpion’s digestive system (the anus is situated posteriorly on metasomal segment V) and the ability to inject venom by stinging. After autotomy, scorpions do not defecate and can only capture small prey items. However, males can survive and mate successfully for up to eight months in the laboratory. In spite of diminished predation ability after autotomy, survival allows males to reproduce. Autotomy in Ananteris therefore appears to be an effective, adaptive, anti-predation escape mechanism. PMID:25629529

Mattoni, Camilo I.; García-Hernández, Solimary; Botero-Trujillo, Ricardo; Ochoa, José A.; Ojanguren-Affilastro, Andrés A.; Pinto-da-Rocha, Ricardo; Prendini, Lorenzo

2015-01-01

289

Short-tailed shrews: Toxicity and residue relationships of DDT, dieldrin, and endrin  

USGS Publications Warehouse

Experiments involving dietary toxicity and residue relationships of DDT, dieldrin, and endrin were conducted with short-tailed shrews. Dietary concentrations of DDT dissolved in vegetable oils were usually more toxic than diets containing comparable amounts of powdered DDT. Younger shrews, particularly females, were more tolerant of powdered DDT than older animals; yet, there were no conspicuous age differences in toxicity of DDT dissolved in oils. In comparison to other mammals, short-tailed shrews are not unusually sensitive to DDT, dieldrin, or endrin on the basis of two-week feeding tests. The influence of age and sex on toxicity of DDT, endrin, and dieldrin was sometimes more important than body weight. Of those shrews of the same age and sex that were fed the same dietary dosage, heavier shrews were more tolerant than lighter individuals; and, heavier shrews tended to lose a greater percentage of body weight before death. There was a range of 15 to 105 DDT equivalents in brains of shrews dying on dietary dosages of DDT. Six shrews fed a high level of DDT seemed to have unusual metabolite capabilities and died with apparent lethal levels of DDD in their brains. Levels of dieldrin in brains of shrews that died on a dietary dosage of dieldrin ranged from 3.7 to 12.6 ppm. In the rates of gain and loss experiments where shrews were given diets containing 400 ppm DDT or 50 ppm dieldrin up to 17 days, high residues were noted in tissues of shrews after two weeks on a contaminated diet and a few died at that time. After shrews were placed on clean food, it was determined that >50% of the dieldrin residues in carcass and brain were lost in 50% of residues of DDT and metabolites in brains after 2 weeks on clean food; males lost nearly 50% of residues in carcasses after two weeks on clean food compared with a loss of only 11% in females.

Blus, L.J.

1978-01-01

290

Effects of tail docking on health and performance of beef cattle in confined, slatted-floor feedlots.  

PubMed

Tail docking of feedlot cattle is a management practice used in some confined, slatted-floor feedlots of the midwestern United States. Justification for tail docking in these management systems is to reduce tail injuries and their sequelae and improve performance, but limited evidence exists to support these claims. The primary objective of this study was to determine the effect of tail docking on performance, carcass traits, and health parameters after tail docking in feedlot cattle raised in slatted-floor feedlots. Three separate trials were performed. Trial 1 consisted of 140 Angus-cross (370-kg) yearling steers that spent 144 to 160 days on feed (DOF). Trial 2 consisted of 137 Angus-cross (255-kg) weaned steers that spent 232 DOF. Trial 3 consisted of 102 Holstein steers (370 kg) that spent 185 to 232 DOF. Cattle were randomly assigned to 1 of 2 treatment groups: docked (DK) or control (CN). All steers received an epidural following surgical preparation of the sacrococcygeal area and postoperative intravenous flunixin meglumine. Approximately two-thirds of the tail of DK calves was removed and an elastrator band was placed near the tail tip for hemostasis. Performance parameters collected included daily gain, final weight, feed intake, and feed efficiency. Carcass data included HCW, subcutaneous fat thickness, LM area, KPH percent, marbling, USDA yield grade, and USDA quality grade. Morbidity, mortality, incidence of lameness, and incidence of tail lesions were recorded. Across all 3 trials, there was no significant effect (P < 0.05) of treatment on performance parameters, carcass traits, or health parameters. In all 3 trials, tail tip injuries occurred in 60 to 76% of undocked (CN) calves, developed while living in the slatted-floor environment, compared to 100% of DK calves, whose injuries were a result of the tail docking procedure. We were unable to identify a performance or significant health advantage to tail docking. However, tail tip injuries still occur in cattle raised in slatted-floor facilities. Because of the animal welfare issues associated with tail docking and tail injuries, we recommend pursuing alternative solutions to reducing the incidence of tail tip injury in feedlot cattle housed in confined slatted-floor facilities. PMID:24987071

Kroll, L K; Grooms, D L; Siegford, J M; Schweihofer, J P; Metz, K; Rust, S R

2014-09-01

291

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 PMID:1534556

Sandmeier, H; Iida, S; Arber, W

1992-01-01

292

Static strain and vibration characteristics of a metal semimonocoque helicopter tail cone of moderate size  

NASA Technical Reports Server (NTRS)

The results are presented of an analytic and experimental research program involving a Sikorsky S-55 helicopter tail cone directed ultimately to the improved structural analysis of airframe substructures typical of moderate sized helicopters of metal semimonocoque construction. Experimental static strain and dynamic shake-testing measurements are presented. Correlation studies of each of these tests with a PC-based finite element analysis (COSMOS/M) are described. The tests included static loadings at the end of the tail cone supported in the cantilever configuration as well as vibrational shake-testing in both the cantilever and free-free configurations.

Bielawa, Richard L.; Hefner, Rachel E.; Castagna, Andre

1991-01-01

293

Malignant mesenchymal tumors in two white-tailed jack rabbits (Lepus townsendii).  

PubMed

Two white-tailed jack rabbits (Lepus townsendii) with proliferative lesions in their internal organs were submitted to the Canadian Cooperative Wildlife Health Centre (Saskatoon, Saskatchewan, Canada) for necropsy because of concern that dogs that had contact with the hares might have been exposed to an infectious disease. In both hares, the primary diagnosis was neoplasia. One hare had metastatic leiomyosarcoma and uterine fibroma, the other had metastatic mesenchymal tumors involving the liver and mesentery. These cases represent the only reports of malignant mesenchymal tumors in white-tailed jack rabbits that we have found in the literature. PMID:15650095

Jardine, Claire; Wobeser, Gary A; Simko, Elemir

2004-10-01

294

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. PMID:16504013

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

2006-01-01

295

Tail vaccination in cats: a pilot study.  

PubMed

Feline injection site sarcomas affect 1-10 cats per every 10,000 vaccinated and are associated with high mortality. Radical resection may be curative, but is often associated with prolonged recovery, disfigurement and loss of function when tumors occur at currently recommended injection sites. The objective of this study was to assess alternatives to currently recommended vaccination sites in terms of preference by oncology practitioners, ease of injection and serological responses. Surgical, radiation and medical oncology practitioners were surveyed regarding their preference for vaccination sites based on the ease of tumor resection. A six-point Likert scale was used to measure each cat's behavioral reaction to vaccination when injected subcutaneously in the distal hind limb or the distal tail. Serum collected before and 1-2 months after vaccination was tested for antibody titers against feline panleukopenia virus (FPV) and rabies virus (RV). The preferred sites for vaccination by 94 oncology practitioners were below the stifle (41%) and the tail (30%). There were no significant differences in the cats' behavioral reaction to vaccination below the stifle (n = 31) and in the distal tail (n = 29). Of the cats seronegative for FPV at the time of vaccination, 100% developed protective antibody titers (?40) against FPV 1-2 months following vaccination. For cats seronegative for RV, all but one cat (tail vaccine) developed acceptable antibody titers (?0.5 IU/ml) against RV. Tail vaccination was well tolerated and elicited similar serological responses to vaccination in the distal limbs. PMID:24108201

Hendricks, Cleon G; Levy, Julie K; Tucker, Sylvia J; Olmstead, Shaye M; Crawford, P Cynda; Dubovi, Edward J; Hanlon, Cathleen A

2014-04-01

296

THE DUST TAIL OF ASTEROID (3200) PHAETHON  

SciTech Connect

We report the discovery of a comet-like tail on asteroid (3200) Phaethon when imaged at optical wavelengths near perihelion. In both 2009 and 2012, the tail appears {approx}>350'' (2.5 Multiplication-Sign 10{sup 8} m) in length and extends approximately in the projected anti-solar direction. We interpret the tail as being caused by dust particles accelerated by solar radiation pressure. The sudden appearance and the morphology of the tail indicate that the dust particles are small, with an effective radius {approx}1 {mu}m and a combined mass {approx}3 Multiplication-Sign 10{sup 5} kg. These particles are likely products of thermal fracture and/or desiccation cracking under the very high surface temperatures ({approx}1000 K) experienced by Phaethon at perihelion. The existence of the tail confirms earlier inferences about activity in this body based on the detection of anomalous brightening. Phaethon, the presumed source of the Geminid meteoroids, is still active.

Jewitt, David; Li Jing [Department of Earth and Space Sciences, University of California at Los Angeles, 595 Charles Young Drive East, Los Angeles, CA 90095-1567 (United States); Agarwal, Jessica, E-mail: jewitt@ucla.edu [Max Planck Institute for Solar System Research, Max-Planck-Str. 2, D-37191 Katlenburg-Lindau (Germany)

2013-07-10

297

The Sup35 Omnipotent Suppressor Gene Is Involved in the Maintenance of the Non-Mendelian Determinant [Psi(+)] in the Yeast Saccharomyces Cerevisiae  

PubMed Central

The SUP35 gene of yeast Saccharomyces cerevisiae encodes a 76.5-kD ribosome-associated protein (Sup35p), the C-terminal part of which exhibits a high degree of similarity to EF-1? elongation factor, while its N-terminal region is unique. Mutations in or overexpression of the SUP35 gene can generate an omnipotent suppressor effect. In the present study the SUP35 wild-type gene was replaced with deletion alleles generated in vitro that encode Sup35p lacking all or a part of the unique N-terminal region. These 5'-deletion alleles lead, in a haploid strain, simultaneously to an antisuppressor effect and to loss of the non-Mendelian determinant [psi(+)]. The antisuppressor effect is dominant while the elimination of the [psi(+)] determinant is a recessive trait. A set of the plasmid-borne deletion alleles of the SUP35 gene was tested for the ability to maintain [psi(+)]. It was shown that the first 114 amino acids of Sup35p are sufficient to maintain the [psi(+)] determinant. We propose that the Sup35p serves as a trans-acting factor required for the maintenance of [psi(+)]. PMID:8088512

Ter-Avanesyan, M. D.; Dagkesamanskaya, A. R.; Kushnirov, V. V.; Smirnov, V. N.

1994-01-01

298

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. PMID:21965397

N?ancucheo, Ivan; Johnson, D. Barrie

2011-01-01

299

A simple versatile method for measuring tail cuff systolic blood pressure in conscious rats.  

PubMed

1. The non-invasive measurement of tail cuff systolic blood pressure in conscious rats is routinely used in long-term cardiovascular studies. There are a number of commercially available tail cuff systems, however, these apparatus are generally expensive and are dedicated for single-task operations. In the present study, a simple method for measuring systolic blood pressure, which requires only minor modifications to the existing hardware found in most cardiovascular laboratories, is described. 2. Systolic blood pressure measurements were made in the conventional manner by determining the systolic blood pressure which coincided with the restoration of the caudal artery pulse. This was achieved by using an inexpensive piezo-electric pulse transducer to detect the pulse, and this was coupled to a standard data-acquisition system (MacLab, ADInstruments) normally set up to record blood pressure. This method was compared with another established tail cuff method, as well as with direct intra-arterial recordings. 3. It was found that the results obtained using both tail cuff systems were in good agreement when systolic blood pressure was measured in Wistar-Kyoto rats and spontaneously hypertensive rats. In addition, systolic blood pressure was measured over 4 weeks in 2K1C rats and sham-operated rats, with both tail cuff methods producing similar results, which were not significantly different from direct intra-arterial recordings in the same animals. 4. Thus, in the present study, with only minor modifications, the same equipment was used for both direct and indirect determinations of systolic blood pressure. This situation differs from other conventional tail cuff systems since these items are designed for a single purpose. Therefore, the current method using piezo-electric sensor/MacLab-technology should be viewed as a relatively simple, flexible and cheap alternative method to measure tail cuff systolic blood pressure in conscious rats. PMID:9337632

Widdop, R E; Li, X C

1997-09-01

300

Experimental persistent infection with bovine viral diarrhea virus in white-tailed deer.  

PubMed

Bovine viral diarrhea virus (BVDV) infections cause substantial economic losses to the cattle industries. Persistently infected (PI) cattle are the most important reservoir for BVDV. White-tailed deer (Odocoileus virginianus) are the most abundant species of wild ruminants in the United States and contact between cattle and deer is common. If the outcome of fetal infection of white-tailed deer is similar to cattle, PI white-tailed deer may pose a threat to BVDV control programs. The objective of this study was to determine if experimental infection of pregnant white-tailed deer with BVDV would result in the birth of PI offspring. Nine female and one male white-tailed deer were captured and housed at a captive deer isolation facility. After natural mating had occurred, all does were inoculated intranasally at approximately 50 days of pregnancy with 10(6) CCID(50) each of a BVDV 1 (BJ) and BVDV 2 (PA131) strain. Although no clinical signs of BVDV infection were observed or abortions detected, only one pregnancy advanced to term. On day 167 post-inoculation, one doe delivered a live fawn and a mummified fetus. The fawn was translocated to an isolation facility to be hand-raised. The fawn was determined to be PI with BVDV 2 by serial virus isolation from serum and white blood cells, immunohistochemistry on skin biopsy, and RT-PCR. This is the first report of persistent infection of white-tailed deer with BVDV. Further research is needed to assess the impact of PI white-tailed deer on BVDV control programs in cattle. PMID:17353103

Passler, Thomas; Walz, Paul H; Ditchkoff, Stephen S; Givens, M Daniel; Maxwell, Herris S; Brock, Kenny V

2007-06-21

301

Internucleosomal Interactions Mediated by Histone Tails Allow Distant Communication in Chromatin*  

PubMed Central

Action across long distances on chromatin is a hallmark of eukaryotic transcriptional regulation. Although chromatin structure per se can support long-range interactions, the mechanisms of efficient communication between widely spaced DNA modules in chromatin remain a mystery. The molecular simulations described herein suggest that transient binary internucleosomal interactions can mediate distant communication in chromatin. Electrostatic interactions between the N-terminal tails of the core histones and DNA enhance the computed probability of juxtaposition of sites that lie far apart along the DNA sequence. Experimental analysis of the rates of communication in chromatin constructs confirms that long-distance communication occurs efficiently and independently of distance on tail-containing, but not on tailless, chromatin. Taken together, our data suggest that internucleosomal interactions involving the histone tails are essential for highly efficient, long-range communication between regulatory elements and their targets in eukaryotic genomes. PMID:22518845

Kulaeva, Olga I.; Zheng, Guohui; Polikanov, Yury S.; Colasanti, Andrew V.; Clauvelin, Nicolas; Mukhopadhyay, Swagatam; Sengupta, Anirvan M.; Studitsky, Vasily M.; Olson, Wilma K.

2012-01-01

302

Host factor Hfq of Escherichia coli stimulates elongation of poly(A) tails by poly(A) polymerase I  

PubMed Central

Current evidence suggests that the length of poly(A) tails of bacterial mRNAs result from a competition between poly(A) polymerase and exoribonucleases that attack the 3? ends of RNAs. Here, we show that host factor Hfq is also involved in poly(A) tail metabolism. Inactivation of the hfq gene reduces the length of poly(A) tails synthesized at the 3? end of the rpsO mRNA by poly(A) polymerase I in vivo. In vitro, Hfq stimulates synthesis of long tails by poly(A) polymerase I. The strong binding of Hfq to oligoadenylated RNA probably explains why it stimulates elongation of primers that already harbor tails of 20–35 A. Polyadenylation becomes processive in the presence of Hfq. The similar properties of Hfq and the PABPII poly(A) binding protein, which stimulates poly(A) tail elongation in mammals, indicates that similar mechanisms control poly(A) tail synthesis in prokaryotes and eukaryotes. PMID:10677490

Hajnsdorf, Eliane; Régnier, Philippe

2000-01-01

303

Microsatellite markers in white-tailed deer.  

PubMed

A genomic library of DNA from white-tailed deer was constructed for the isolation of d(AC)n microsatellite repeats. PCR primers were designed from regions flanking each repeat and used to amplify DNA samples from a pedigreed herd of white-tailed deer and other artiodactyls. Allelic frequencies, PIC values, and heterozygosity values are reported for five polymorphic markers scored in 41 animals. Homologs of two of the five markers were assigned to bovine chromosomes 4 and 23, respectively, using a panel of bovine+hamster hybrid somatic cell lines. PMID:7658002

DeWoody, J A; Honeycutt, R L; Skow, L C

1995-01-01

304

Pioneer fauna of nepheline-containing tailings  

NASA Astrophysics Data System (ADS)

The zoological analysis of nepheline-containing sands deposited in tailings 10-40 years ago showed that the pioneer colonists of this technogenic substrate are collembolan and mites, whose proportions depend on the succession of the bacterial and fungal components of the microbiota. The pioneer groups of mesofauna on 10- to 30-year-old tailings include carnivorous herpetobiontic arthropods and phytophagous insects. An impoverished version of the fauna of northern-taiga podzols is developed in the sands rehabilitated more than 40 years ago.

Zenkova, I. V.; Kalmykova, V. V.; Liskovaya, A. A.

2009-08-01

305

Comparison of tar sands and phosphatic clay tailings properties, disposal, and reclamation options  

SciTech Connect

The tar sands industry of northern Alberta, much like the phosphate mining industry of Florida, is having to deal with the long term management of a fine-grained tailings waste. The production of synthetic crude from surface deposits of tar sands results in a combined tailings mixture of sand, bitumen, and clay. The phosphate industry bonification process separates the clay and sand waste streams at the plant and these materials are generally deposited in separate disposal areas. Both the tar sands fine tailings and the waste phosphatic clays exhibit engineering characteristics associated with highly plastic clays. This behavior is typically characterized by large changes in void ratio and permeability with changes in effective stress. Recent technology exchanges between the phosphate and tar sands industries reveal some encouraging opportunities for waste disposal and reclamation planning in the tar sands industry. Studies involving the mixing of mature fine oil sands tailings and sand (with and without chemical additives) have provided some improvements in the tar sands tailings material consolidation and permeability properties.

Ericson, W.A.; Carrier, W.D. III [BCI, Lakeland, FL (United States); Burns, R. [Suncor, Alberta (Canada)

1995-12-31

306

Stability and control characteristics of a monoplannar missile configuration with two low-profile tail arrangements at Mach numbers from 1.70 to 2.86  

NASA Technical Reports Server (NTRS)

An experimental wind tunnel investigation has been made to determine the longitudinal and lateral aerodynamic stability and control characteristics of two tail fin arrangements of a monowing missile model. Both a conventional cruciform and a low profile tail arrangement were tested. The results indicate that the tail surfaces of both configurations were effective in producing pitch control. It was also concluded that both are effective in producing roll and yaw control that is accompanied by proverse yaw and roll, respectively. The conventional cruciform tail produces the most roll and yaw control.

Blair, A. B., Jr.

1977-01-01

307

The interaction network of rhodopsin involving the heterotrimeric G-protein transducin and the monomeric GTPase Rac1 is determined by distinct binding processes.  

PubMed

The monomeric G-protein Rac1, a member of the family of Rho/Rac/Cdc42 GTPases, is involved in light-induced photoreceptor degeneration, but its specific role remains elusive. In particular, reports on Rac1 interacting with the visual pigment rhodopsin are puzzling and need a more quantitative examination. We probed the presence of Rac1 in rod outer segments by immunohistochemical staining of bovine retinae and western blot analysis of isolated rod outer segments. Rac1 was present throughout the whole retina except in the outer and inner nuclear layers, but was strongly expressed in photoreceptor cells. Rac1 was distributed in three different fractions of rod outer segments: one fraction was soluble in detergents, a second fraction cosegregated with lipid rafts, and a third fraction was associated with lipid bilayer free axonemal/cytoskeletal structures. We also investigated the interaction between rhodopsin and Rac1 by using surface plasmon resonance spectroscopy under dark and light conditions. Biophysical interaction studies revealed that Rac1 could interact with rhodopsin, but in a light-independent manner, and kinetic analysis indicated that binding of Rac1 occurred with lower affinity and speed than the association of transducin and rhodopsin. Thus, in dark-adapted rod cells, Rac1 cannot compete with transducin for binding to rhodopsin, and signalling can proceed normally. Instead, the concentration of transducin has to drop significantly so that Rac1 can bind to rhodopsin; in the outer segment, this occurs only under intense illumination, when transducin is translocated to the inner segment. PMID:25243418

Köster, Maike; Dell'Orco, Daniele; Koch, Karl-Wilhelm

2014-12-01

308

The interrelationship of research in the laboratory and the field to assess hydration status and determine mechanisms involved in water regulation during physical activity.  

PubMed

Changes in skin blood and sweating are the primary mechanisms for heat loss in humans. A hot, humid environment concomitant with dehydration limits the ability to increase skin blood flow for the purpose of transferring heat from the body core to skin surface and evaporate sweat to maintain core temperature within safe limits during exercise. Adequate hydration improves thermoregulation by maintaining blood volume to support skin blood flow and sweating. Humans rely on fluid intake to maintain total body water and blood volume, and have developed complex mechanisms to sense changes in the amount and composition of fluid in the body. This paper addresses the interrelationship of research in the laboratory and the field to assess hydration status involved in body water and temperature regulation during exercise. In the controlled setting of a research laboratory, investigators are able to investigate the contributions of volume and tonicity of fluid in the plasma to body water and temperature regulation during exercise and recovery. For example, laboratory studies have shown that tonicity in a rehydration beverage maintains the thirst mechanism (and stimulates drinking), and contributes to the ongoing stimulation of renal fluid retention hormones, ultimately leading to a more complete rehydration. Research in the field cannot control the environment precisely, but these studies provide a natural, 'real-life' setting to study fluid and temperature regulation during exercise. The conditions encountered in the field are closest to the environment during competition, and data collected in the field can have an immediate impact on performance and safety during exercise. There is an important synergy between these two methods of collecting data that support performance and protect athletes from harm during training and improve performance during competition. PMID:24791921

Stachenfeld, Nina S

2014-05-01

309

The terminal six amino-acids of the carboxy cytoplasmic tail of CD36 contain a functional domain implicated in the binding and capture of oxidized low-density lipoprotein.  

PubMed Central

CD36, a major adhesion molecule expressed by monocytes/macrophages, plays a key role in the binding and internalization of oxidized low-density lipoprotein (OxLDL). This adhesion molecule, a member of an important scavenger receptor family, contains a very short C-terminal cytoplasmic tail that is known to induce intracellular signalling events. However, the domains on the cytoplasmic tail involved in such signal transduction are unknown. In this study, we have investigated the functional components of the cytoplasmic tail by site-directed mutagenesis coupled with functional OxLDL and monoclonal antibody (mAb) binding studies. Seven truncated or punctual CD36 constructs, localized in the cytoplasmic tail, were produced by site-directed mutagenesis. Each construct was stably expressed in HEK293 cells. We used a quantitative and a qualitative method, labelling OxLDL with either iodine or rhodamine, to determine the functional importance of the cytoplasmic domains in OxLDL internalization. Results indicate that: (1) a deletion of the last amino-acid (construct K472STOP) significantly reduces, compared with wild-type, the binding, internalization and degradation of OxLDL; (2) truncation of the last six amino-acids (construct R467STOP) significantly reduces OxLDL binding; (3) the above two constructs (K472STOP and R467STOP) showed a reduced rate of OxLDL internalization compared with wild-type; (4) the binding and rate of internalization of an anti-CD36 monoclonal antibody (10/5) was not affected by the above mentioned mutants (K472STOP and R467STOP), compared with wild-type. This study shows, for the first time, a specific site on the CD36 cytoplasmic tail that is critical for the binding, endocytosis and targeting of OxLDL. PMID:12023894

Malaud, Eric; Hourton, Delphine; Giroux, Louise Marie; Ninio, Ewa; Buckland, Robin; McGregor, John L

2002-01-01

310

TIDAL TAILS OF MINOR MERGERS: STAR FORMATION EFFICIENCY IN THE WESTERN TAIL OF NGC 2782  

SciTech Connect

While major mergers and their tidal debris are well studied, they are less common than minor mergers (mass ratios {approx}< 0.3). The peculiar spiral NGC 2782 is the result of a merger between two disk galaxies with a mass ratio of {approx}4: 1 occurring {approx}200 Myr ago. This merger produced a molecular and H I-rich, optically bright eastern tail and an H I-rich, optically faint western tail. Non-detection of CO in the western tail by Braine et al. suggested that star formation had not yet begun to occur in that tidal tail. However, deep H{alpha} narrowband images show evidence of recent star formation in the western tail. Across the entire western tail, we find the global star formation rate per unit area ({Sigma}{sub SFR}) to be several orders of magnitude less than expected from the total gas density. Together with extended FUV+NUV emission from Galaxy Evolution Explorer along the tail, this indicates a low global star formation efficiency in the tidal tail producing lower mass star clusters. The H II region that we observed has a local (few-kiloparsec scale) {Sigma}{sub SFR} from H{alpha} that is less than that expected from the total gas density, which is consistent with other observations of tidal debris. The star formation efficiency of this H II region inferred from the total gas density is low, but normal when inferred from the molecular gas density. These results suggest the presence of a very small, locally dense region in the western tail of NGC 2782 or of a low-metallicity and/or low-pressure star-forming region.

Knierman, Karen; Scowen, Paul; Jansen, Rolf A. [School of Earth and Space Exploration, Arizona State University, 550 East Tyler Mall, Room PSF-686 (P.O. Box 871404), Tempe, AZ 85287-1404 (United States); Knezek, Patricia M. [WIYN Consortium, Inc., 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Wehner, Elizabeth, E-mail: karen.knierman@asu.edu, E-mail: paul.scowen@asu.edu, E-mail: rolf.jansen@asu.edu, E-mail: pknezek@noao.edu, E-mail: ewehner@haverford.edu [Department of Astronomy, Haverford College, Haverford, PA 19041 (United States)

2012-04-10

311

The Tail Domain Is Essential but the Head Domain Dispensable for C. elegans Intermediate Filament IFA-2 Function  

PubMed Central

The intermediate filament protein IFA-2 is essential for the structural integrity of the Caenorhabditis elegans epidermis. It is one of the major components of the fibrous organelle, an epidermal structure comprised of apical and basal hemidesmosomes linked by cytoplasmic intermediate filaments that serve to transmit force from the muscle to the cuticle. Mutations of IFA-2 result in epidermal fragility and separation of the apical and basal epidermal surfaces during postembryonic growth. An IFA-2 lacking the head domain fully rescues the IFA-2 null mutant, whereas an IFA-2 lacking the tail domain cannot. Conversely, an isolated IFA-2 head was able to localize to fibrous organelles whereas the tail was not. Taken together these results suggest that the head domain contains redundant signals for IF localization, whereas non-redundant essential functions map to the IFA-2, tail, although the tail is unlikely to be directly involved in fibrous organelle localization. PMID:25742641

Williams, Kyle; Williams, Kristen; Baucher, Hallie M.; Plenefisch, John

2015-01-01

312

Structural determinants within residues 180-199 of the rodent. alpha. 5 nicotinic acetylcholine receptor subunit involved in. alpha. -bungarotoxin binding  

SciTech Connect

Synthetic peptides corresponding to sequence segments of the nicotinic acetylcholine receptor (nAChR) {alpha} subunits have been used to identify regions that contribute to formation of the binding sites for cholinergic ligands. The authors have previously defined {alpha}-bungarotoxin ({alpha}-BTX) binding sequences between residues 180 and 199 of a putative rat neuronal nAChR {alpha} subunit, designated {alpha}5, and between residues 181 and 200 of the chick neuronal {alpha}7 and {alpha}8 subunits. These sequences are relatively divergent compared with the Torpedo and muscle nAChR {alpha}1 {alpha}-BTX binding sites, which indicates a serious limitation of predicting functional domains of proteins based on homology in general. Given the highly divergent nature of the {alpha}5 sequence, they were interested in determining the critical amino acid residues for {alpha}-BTX binding. In the present study, the effects of single amino acid substitutions of Gly or Ala for each residue of the rat {alpha}(180-199) sequence were tested, using a competition assay, in which peptides compete for {sup 125}I-{alpha}-BTX binding with native Torpedo nAChR. These results indicate that a disulfide bridge between the vicinal cysteines at positions 191 and 192 of the {alpha}5 sequence is not an absolute requirement for {alpha}-BTX binding activity.

McLane, K.E.; Xiadong Wu; Conti-Tronconi, B.M. (Univ. of Minnesota, St. Paul (United States))

1991-11-05

313

Impact of ozonation on particle aggregation in mature fine tailings.  

PubMed

The extraction of bitumen from the oil sands in Canada generates tonnes of mature fine tailings (MFT), consisting of a mineral matrix of sand, clay, and water, which without treatment requires thousands of years to fully consolidate. We assessed the performance of a novel ozonation method designed to enhance the settling of MFT and explored the mechanisms involved. The solid content of MFT obtained from oil sands tailings was adjusted to 1, 3, 5 wt % with water before applying 15, 30, and 60 min of ozonation. MFT settled after a short (15 min) ozonation treatment, resulting in a sample with clear released water on the top and condensed sludge at the bottom. The water chemistry characteristics, particles' surface charge and chemical bonding were measured. Ozonation led to the increased organic acids concentrations in MFT suspension through converting of organic matter from high to low molecular weight, and detaching organic coating on MFT particles. The pH and the concentrations of ions in the MFT suspension were changed significantly, an association of metal ions with MFT particles was promoted, and the surface charges of MFT particles were neutralized. Consequently, the MFT suspension was destabilized and MFT particle precipitation was observed. PMID:25214072

Liang, Jiaming; Tumpa, Fahmida; Pérez Estrada, Leonidas; Gamal El-Din, Mohamed; Liu, Yang

2014-12-15

314

Microbiological and geochemical characterization of fluvially deposited sulfidic mine tailings  

SciTech Connect

The fluvial deposition of mine tailings generated from historic mining operations near Butte, Montana, has resulted in substantial surface and shallow groundwater contamination along Silver Bow Creek. Biogeochemical processes in the sediment and underlying hyporheic zone were studied in an attempt to characterize interactions consequential to heavy-metal contamination of shallow groundwater. Sediment cores were extracted and fractionated based on sediment stratification. Subsamples of each fraction were assayed for culturable heterotrophic microbiota, specific microbial guilds involved in metal redox transformations, and both aqueous- and solid-phase geochemistry. Populations of cultivable Fe(III)-reducing bacteria were most prominent in the anoxic, circumneutral pH regions associated with a ferricrete layer or in an oxic zone high in organic carbon and soluble iron. Sulfur- and iron-oxidizing bacteria were distributed in discrete zones throughout the tailings and were often recovered from sections at and below the anoxic groundwater interface. Sulfate-reducing bacteria were also widely distributed in the cores and often occurred in zones overlapping iron and sulfur oxidizers. Sulfate-reducing bacteria were consistently recovered from oxic zones that contained high concentrations of metals in the oxidizable fraction. Altogether, these results suggest a highly varied and complex microbial ecology within a very heterogeneous geochemical environment. Such physical and biological heterogeneity has often been overlooked when remediation strategies for metal contaminated environments are formulated.

Wielinga, B.; Lucy, J.K.; Moore, J.N.; Seastone, O.F.; Gannon, J.E. [Univ. of Montana, Missoula, MT (United States)

1999-04-01

315

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. PMID:23283946

Pietilä, Maija K.; Laurinmäki, Pasi; Russell, Daniel A.; Ko, Ching-Chung; Jacobs-Sera, Deborah; Butcher, Sarah J.

2013-01-01

316

Enhancing the Safety of Tailings Management Facilities  

Microsoft Academic Search

Unsafe tailings management facilities (TMFs) have caused serious accidents in Europe (e.g., Baia Mare, Romania, in 2000, Aznalcóllar, Spain, in 1998, and Stava, Italy, in 1985), 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

Tamás Meggyes; Ernst Niederleithinger; Karl Josef Witt; Mihály Csövári; Katarzyna Kreft-Burman; Jon Engels; Chris McDonald; Karl Ernst Roehl

2008-01-01

317

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...

318

Controlled Impact Demonstration (CID) tail camera video  

NASA Technical Reports Server (NTRS)

The Controlled Impact Demonstration (CID) was a joint research project by NASA and the FAA to test a survivable aircraft impact using a remotely piloted Boeing 720 aircraft. The tail camera movie is one shot running 27 seconds. It shows the impact from the perspective of a camera mounted high on the vertical stabilizer, looking forward over the fuselage and wings.

1984-01-01

319

TAIL-MOUNTED RADIO TRANSMITTERS FOR WATERFOWL  

Microsoft Academic Search

We successfully tested tail-mounted radio transmitters on Pink-footed Geese (Anser brachyrhynchus), Barnacle Geese (Branta leucopsis), Brant (Branta bernicla) and Eur- asian Wigeon (Anas penelope). The range of detection of the transmitters was approximately 1 km and some birds were tracked for up to 4 mo. Movements and activity of the birds were not affected by the packages. We conclude that

JEAN-FRANCOIS GIROUX; DAVID V. BELL; STEVE PERCIVAL; RON W. SUMMERS

320

URANIUM MILL TAILINGS RADON FLUX CALCULATIONS  

E-print Network

URANIUM MILL TAILINGS RADON FLUX CALCULATIONS PIÑON RIDGE PROJECT MONTROSE COUNTY, COLORADO (EFRC) proposes to license, construct, and operate a conventional acid leach uranium and vanadium mill storage pad, and access roads. The mill is designed to process ore containing uranium and vanadium

321

Ferric leaching of copper slag flotation tailings  

Microsoft Academic Search

The pyrometallurgical production of copper generates slags, a residue with a significant content of this metal. Copper can be recovered from the slags by froth flotation after cooling, crushing, and grinding. The obtained Cu-concentrate is sent to the pyrometallurgical process. If grinding is not fine enough for efficient flotation, copper is lost in tailings. In this paper, the ferric leaching

F. Carranza; N. Iglesias; A. Mazuelos; R. Romero; O. Forcat

2009-01-01

322

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

323

Fluidized-bed combustion of flotation tailings  

Microsoft Academic Search

After mechanical water removal, the flotation tailings containing about 30% moisture are stored in silo (1) which is specially designed for this purpose. The lime required for desulphurizing the flue gas is stored in silo (2) Special silo-discharge device and weigh-feeders pass the two materials to the mixing screw in proportional rates in accordance with the sulphur content and guaranteed

Belting

1979-01-01

324

14. Credit PED. Downstream elevation, near completion, showing tail race ...  

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

14. Credit PED. Downstream elevation, near completion, showing tail race and trestle used to carry excavated rock and construction materials across tail race. Photo c. 1909. - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

325

On the Queue Tail Asymptotics for General Multifractal Traffic  

E-print Network

On the Queue Tail Asymptotics for General Multifractal Traffic S´andor Moln´ar1 , Trang Dinh Dang1 3889, Fax: (361) 463 3107 {molnar, trang, maricza}@ttt-atm.ttt.bme.hu Abstract. The tail asymptotics

Molnár, Sándor

326

Diets of short-tailed shearwaters in the southeastern Bering Sea  

NASA Astrophysics Data System (ADS)

In the late 1990s, the southeastern Bering Sea exhibited a number of anomalous conditions, including a major die-off of short-tailed shearwaters ( Puffinus tenuirostris), a trans-equatorial migrant that constitutes a major portion of the marine bird biomass in the southeastern Bering Sea. As part of a larger study of the ecological role of the inner or structural front over the southeastern Bering Sea shelf, in 1997-1999, we collected short-tailed shearwaters to determine diet composition. In spring 1997, we found that short-tailed shearwaters were consuming predominately the euphausiid Thysanoessa raschii, a diet expected on the basis of past studies. However, in subsequent years, short-tailed shearwater diets in spring contained increasingly larger proportions of fish, in particular, sandlance ( Ammodytes hexapterus), as well as other species of euphausiids ( T. inermis in 1999). In summer and fall collections, short-tailed shearwater diets were more varied than in spring, and included both fish (age-0 gadids, 21-35% by weight) and a wider variety of euphausiid species (T. inermis and T. spinifera). In summer and fall, crab zoea (August 1998) and copepods (August 1999) were eaten by shearwaters collected while feeding within the inner front. Diets in 1997-1999 were broader than those found in previous studies of short-tailed shearwaters over the inner shelf and Bristol Bay, which had documented diets composed almost solely of T. raschii. Our data are consistent with the hypothesis that euphausiids were less available to short-tailed shearwaters foraging over the middle and coastal domains of the southeastern Bering Sea in 1997-1999 than has previously been true. Our results are also consistent with hypothesis that the inner front can affect the availability of prey to shearwaters.

Hunt, George L.; Baduini, Cheryl; Jahncke, Jaime

2002-12-01

327

Summary of the engineering assessment of inactive uranium-mill tailings: Canonsburg Site, Canonsburg, Pennsylvania  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has evaluated the Canonsburg site in order to assess the problems resulting from the existence of radioactive residues at Canonsburg, Pennsylvania. This engineering assessment has included the preparation of topographic maps, 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 remedial actions. Radon gas released from the approximately 300,000 tons of tailings and contaminated soil at the Canonsburg 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 and off-site decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings and contaminated materials to a remote disposal site and decontamination of the Canonsburg site (Options II through IV). Cost estimates for the four options range from $23,244,000 for stabilization in-place, to $27,052,000 for disposal at a distance of about 17 mi. Three principal alternatives for the reprocessing of the Canonsburg tailings were examined: heap leaching; treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. As required by Public Law 95-604, under whose auspices this project is conducted, the US Department of Energy has solicited expressions of interest in reprocessing the tailings and residues at the Canonsburg site for uranium recovery. Since no such interest was demonstrated, no effort has been made to estimate the value of the residual uranium resource at the Canonsburg site.

Not Available

1982-04-01

328

TailGate: Handling Long-Tail Content with a Little Help from Friends  

E-print Network

is predominantly long-tailed with a limited interest group, specially if one considers notions like Dunbar's number transfer costs as such content has limited number of views. Two recent trends are making this problem

Paris-Sud XI, Université de

329

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

330

Activity and reproduction of the black-tailed jackrabbit in the Coastal Cordgrass Prairie of Texas  

E-print Network

of the variations in daily and seasonal activity pat- terms, and to determine reproductive patterns in the black-tailed jackrabbit (~Le us californicus merriami) 1 in the Coastal Bend area of Texas. Data were collected from June li)66 through August of 1...

Haug, Joseph Carroll

1969-01-01

331

DENSITY-DEPENDENT RESPONSES OF GRAY-TAILED VOLES TO MOWING  

EPA Science Inventory

Voles (Microtus spp.) commonly inhabit forage crops and may cause excessive damage to these crops. owever, cover removal by mowing or haying may cause vole populations to decline. o determine if gray-tailed voles responded to mowing of alfalfa in a density-dependent manner, the a...

332

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

333

Evaluation of an electrified mat as a white-tailed deer (Odocoileus virginianus) barrier  

Microsoft Academic Search

White-tailed deer (Odocoileus virginianus) pose economic and safety problems for agricultural and transportation industries. We tested an electronic mat to determine if it would reduce deer crossing through fence openings. We measured deer intrusions and corn consumption at five sites with charged mats and five sites with non-charged mats. Weekly intrusions at treated sites decreased an average of 95% from

Thomas W. Seamans; David A. Helon

2008-01-01

334

EXPERIMENTAL CONTAGIOUS ECTHYMA IN MULE DEER, WHITE-TAILED DEER, PRONGHORN AND WAPITI1  

Microsoft Academic Search

Hand-reared mule deer fawns (Odocoileus hemionus), white-tailed deer fawns (Odocoileus virginianus), pronghorn fawns (Antilocapra americana) and wapiti calves (Cervus elaphus nelsoni) were exposed to contagious ecthyma lesion material obtained from Rocky Mountain bighorn sheep (Ocis cana- densis canadensis) to determine the susceptibility and pathogenesis in these species. All four species devel- oped mucocutaneous proliferative lesions of the oral cavity, grossly

William R. Lance; Charles P. Hibler; James DeMartini

335

White-tailed Deer are Susceptible to Sheep Scrapie by Intracerebral Inoculation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Interspecies transmission studies afford the opportunity to better understand the potential host range and origins of prion diseases. The purpose of this experiment was to determine susceptibility of white-tailed deer to scrapie after intracerebral inoculation and to compare clinical signs and lesi...

336

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

337

Tail-assisted pitch control in lizards, robots and dinosaurs.  

PubMed

In 1969, a palaeontologist proposed that theropod dinosaurs used their tails as dynamic stabilizers during rapid or irregular movements, contributing to their depiction as active and agile predators. Since then the inertia of swinging appendages has been implicated in stabilizing human walking, aiding acrobatic manoeuvres by primates and rodents, and enabling cats to balance on branches. Recent studies on geckos suggest that active tail stabilization occurs during climbing, righting and gliding. By contrast, studies on the effect of lizard tail loss show evidence of a decrease, an increase or no change in performance. Application of a control-theoretic framework could advance our general understanding of inertial appendage use in locomotion. Here we report that lizards control the swing of their tails in a measured manner to redirect angular momentum from their bodies to their tails, stabilizing body attitude in the sagittal plane. We video-recorded Red-Headed Agama lizards (Agama agama) leaping towards a vertical surface by first vaulting onto an obstacle with variable traction to induce a range of perturbations in body angular momentum. To examine a known controlled tail response, we built a lizard-sized robot with an active tail that used sensory feedback to stabilize pitch as it drove off a ramp. Our dynamics model revealed that a body swinging its tail experienced less rotation than a body with a rigid tail, a passively compliant tail or no tail. To compare a range of tails, we calculated tail effectiveness as the amount of tailless body rotation a tail could stabilize. A model Velociraptor mongoliensis supported the initial tail stabilization hypothesis, showing as it did a greater tail effectiveness than the Agama lizards. Leaping lizards show that inertial control of body attitude can advance our understanding of appendage evolution and provide biological inspiration for the next generation of manoeuvrable search-and-rescue robots. PMID:22217942

Libby, Thomas; Moore, Talia Y; Chang-Siu, Evan; Li, Deborah; Cohen, Daniel J; Jusufi, Ardian; Full, Robert J

2012-01-12

338

Prevalence of infectious agents in free-ranging white-tailed deer in northeastern Mexico.  

PubMed

The objectives of this study were to determine the prevalence of antibodies against brucellosis, leptospirosis, infectious bovine rhinotracheitis virus, and bovine viral diarrhea virus (BVDV) in white-tailed deer (Odocoileus virginianus) in northeastern Mexico. Deer (n=521) were captured from helicopter using a netgun on 15 ranches covering 62,114 ha in the states of Coahuila, Nuevo Leon, and Tamaulipas during spring 2004. The prevalence of antibodies against Leptospira, infectious bovine rhinotracheitis, BVDV, and brucellosis were 5.6, 41.1, 63.5, and 0%, respectively, indicating that white-tailed deer and cattle may share disease agents when cohabiting in northeastern Mexico. PMID:18957659

Cantu, Antonio; Ortega-S, J Alfonso; Mosqueda, Juan; Garcia-Vazquez, Zeferino; Henke, Scott E; George, John E

2008-10-01

339

Complement fixation antigen production for Theileria in white-tailed deer (Odocoileus virginianus)  

E-print Network

for the degree of MASTER OF SCIENCE January 1968 Major Subject: Veterinary Microbiology COMPLEMENT FIXATION ANTIGEN PRODUCTION FOR THEILERIA IN WHITE- TAILED DEER (ODOCOILEUS VIRGINIANUS) A Thesis By FAISAL ABDEL GADIR Approved as to style and content... deer (Dama virginiana) native to Missouri. Schaeffler (25) 'd t'1'tdth g ' Th'1 1 '. Rh' . t 1. I22I dhd thTh'1''T. ThyydTh'1'p in 57 per cent of 1, 630 white-tailed deer (Odocoileus virginianus) killed in Texas. They also determined the seriousness...

Gadir, Faisal Abdel

1968-01-01

340

SPACE USE BY ROUND-TAILED MUSKRATS IN ISOLATED WETLANDS  

E-print Network

SPACE USE BY ROUND-TAILED MUSKRATS IN ISOLATED WETLANDS ROBERT L. SCHOOLEY* AND LYN C. BRANCH at Urbana-Champaign, 1102 S. Goodwin Avenue, Urbana, IL 61801, USA The round-tailed muskrat (Neofiber alleni radiotracked 23 round-tailed muskrats in isolated freshwater wetlands in central Florida. Muskrats used lodges

Branch, Lyn C.

341

MODULARITY PREVENTS TAILS KEITH A. KEARNES AND EMIL W. KISS  

E-print Network

of a minimal set is always nonempty although the tail * *may be empty. When the tail is empty celebrations restrictions on the labeled congruence lattices of algebras in a variety fo* *rce the nonexistence of tails {1 , 2, 3, 4, 5}, is the following. If, for all subalgebras S A2, t* *he labeled congruence

Kiss, Emil

342

Unique Structural Features Facilitate Lizard Tail Kristian W. Sanggaard1  

E-print Network

Unique Structural Features Facilitate Lizard Tail Autotomy Kristian W. Sanggaard1 , Carl Chr shedding of a body part; a renowned example is tail loss among lizards as a response to attempted predation. Although many aspects of lizard tail autotomy have been studied, the detailed morphology and mechanism

Schierup, Mikkel Heide

343

Tail behavior of a Threshold Autoregressive Stochastic Volatility model  

E-print Network

Tail behavior of a Threshold Autoregressive Stochastic Volatility model Aliou DIOP Dominique GUEGAN of the process (t)t. keywords : Tail Behavior, Heavy Tail, Stochastic Volatility Model, Thresh- old as a particular model of the Stochastic Autoregressive Volatility (SARV) model introduced by Andersen (1994

Boyer, Edmond

344

Mechanical differences between lumbar and tail discs in the mouse  

Microsoft Academic Search

The mouse lumbar and tail discs are both used as models to study disc degeneration; however, the mechanical behavior of these two levels has not been compared. The objective of this study was to compare the elastic and viscoelastic mechanical properties of lumbar and tail discs of the mouse under axial compression–tension loading. We hypothesized that tail discs would have

Joseph J. Sarver; Dawn M. Elliott

2005-01-01

345

Research Article Spotlight Surveys for White-Tailed Deer  

E-print Network

ABSTRACT Many monitoring programs for white-tailed deer (Odocoileus virginianus) on both private and public, Odocoileus virginianus, spot- light surveys, variance components, white-tailed deer. One of the primary the white-tailed deer (Odocoileus virginianus). A suite of approaches have been used to look at deer

Ditchkoff, Steve

346

Management and Conservation Immobilization of White-Tailed Deer With  

E-print Network

and effective alternative for immobilization of white-tailed deer (Odocoileus virginianus). During a 2-stage Society. KEY WORDS anesthesia, ketamine, Odocoileus virginianus, telazol, tolazoline, white-tailed deer and Wilson 2002). Currently, few drug combinations meet these criteria for white-tailed deer (Odocoileus

347

Population Ecology Spotlight Surveys for White-Tailed Deer  

E-print Network

ABSTRACT Many monitoring programs for white-tailed deer (Odocoileus virginianus) on both private and public, Odocoileus virginianus, spot- light surveys, variance components, white-tailed deer. One of the primary the white-tailed deer (Odocoileus virginianus). A suite of approaches have been used to look at deer

Ditchkoff, Steve

348

Uranium Mill Tailings Remedial Action Project surface project management plan  

SciTech Connect

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 contamination at 24 inactive uranium processing sites and associated vicinity properties containing uranium mill tailings and related residual radioactive materials.

Not Available

1994-09-01

349

TECHNICAL NOTE Individual identification of Sitka black-tailed deer  

E-print Network

TECHNICAL NOTE Individual identification of Sitka black-tailed deer (Odocoileus hemionus sitkensis for extracting DNA from fecal pellets from Sitka black-tailed deer (Odocoileus hemionus sitkensis) and evaluated. Keywords Alaska Á DNA Á Feces Á Microsatellites Á Odocoileus hemionus sitkensis Á Sitka black-tailed deer

350

Animal model of simulated microgravity: a comparative study of hindlimb unloading via tail versus pelvic suspension  

PubMed Central

The aim of this study was to compare physiological effects of hindlimb suspension (HLS) in tail- and pelvic-HLS rat models to determine if severe stretch in the tail-HLS rats lumbosacral skeleton may contribute to the changes traditionally attributed to simulated microgravity and musculoskeletal disuse in the tail-HLS model. Adult male Sprague-Dawley rats divided into suspended and control-nonsuspended groups were subjected to two separate methods of suspension and maintained with regular food and water for 2 weeks. Body weights, food and water consumption, soleus muscle weight, tibial bone mineral density, random plasma insulin, and hindlimb pain on pressure threshold (PPT) were measured. X-ray analysis demonstrated severe lordosis in tail- but not pelvic-HLS animals. However, growth retardation, food consumption, and soleus muscle weight and tibial bone density (decreased relative to control) did not differ between two HLS models. Furthermore, HLS rats developed similar levels of insulinopenia and mechanical hyperalgesia (decreased PPT) in both tail- and pelvic-HLS groups. In the rat-to-rat comparisons, the growth retardation and the decreased PPT observed in HLS-rats was most associated with insulinopenia. In conclusion, these data suggest that HLS results in mild prediabetic state with some signs of pressure hyperalgesia, but lumbosacral skeleton stretch plays little role, if any, in these pathological changes. PMID:24303103

Chowdhury, Parimal; Long, Ashley; Harris, Gabrielle; Soulsby, Michael E; Dobretsov, Maxim

2013-01-01

351

Spinal cord injury increases the reactivity of rat tail artery to angiotensin II  

PubMed Central

Studies in individuals with spinal cord injury (SCI) suggest the vasculature is hyperreactive to angiotensin II (Ang II). In the present study, the effects of SCI on the reactivity of the rat tail and mesenteric arteries to Ang II have been investigated. In addition, the effects of SCI on the facilitatory action of Ang II on nerve-evoked contractions of these vessels were determined. Isometric contractions of artery segments from T11 (tail artery) or T4 (mesenteric arteries) spinal cord-transected rats and sham-operated rats were compared 6–7 weeks postoperatively. In both tail and mesenteric arteries, SCI increased nerve-evoked contractions. In tail arteries, SCI also greatly increased Ang II-evoked contractions and the facilitatory effect of Ang II on nerve-evoked contractions. By contrast, SCI did not detectably change the responses of mesenteric arteries to Ang II. These findings provide the first direct evidence that SCI increases the reactivity of arterial vessels to Ang II. In addition, in tail artery, the findings indicate that Ang II may contribute to modifying their responses following SCI. PMID:25610365

Al Dera, Hussain; Brock, James A.

2015-01-01

352

Engineering assessment of inactive uranium mill tailings: Lakeview site, Lakeview, Oregon  

SciTech Connect

This 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 constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The three alternative actions presented in this engineering assessment include millsite decontamination with the addition of 3 m of stabilization cover material (Option I) and removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II and III). Cost estimates range from about $6,000,000 for stabilization in-place, to about $7,500,000 for disposal at a distance of about 10 miles. Three alternatives for reprocessing the Lakeview tailings were examined: heap leaching, treatment at an existing mill, and reprocessing at a new conventional mill. The cost of the uranium recovered would be over $450/lb of U/sub 3/O/sub 8/ and hence reprocessing is not economical.

none,

1981-10-01

353

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

2011-05-01

354

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

NASA Technical Reports Server (NTRS)

During MESSENGER's third flyby of Mercury, a series of 2-3 minute long enhancements of the magnetic field in the planet's magnetotail were observed. Magnetospheric substorms at Earth are powered by similar tail loading, but the amplitude is approximately 10 times less and the durations are 1 hr. These observations of extreme loading imply that the relative intensity of substorms at Mercury must be much larger than at Earth. The correspondence between the duration of tail enhancements and the calculated approximately 2 min Dungey cycle, which describes plasma circulation through Mercury's magnetosphere, suggests that such circulation determines substorm timescale. A key aspect of tail unloading during terrestrial substorms is the acceleration of energetic charged particles. Such signatures are puzzlingly absent from the MESSENGER flyby measurements.

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.; Travnicek, Pavel M.; Zurbuchen, Thomas H.

2010-01-01

355

Experimental parametric studies of transonic T-tail flutter. [wind tunnel tests  

NASA Technical Reports Server (NTRS)

Wind-tunnel tests of the T-tail of a wide-body jet airplane were made at Mach numbers up to 1.02. The model consisted of a 1/13-size scaled version of the T-tail, fuselage, and inboard wing of the airplane. Two interchangeable T-tails were tested, one with design stiffness for flutter-clearance studies and one with reduced stiffness for flutter-trend studies. Transonic antisymmetric-flutter boundaries were determined for the models with variations in: (1) fin-spar stiffness, (2) stabilizer dihedral angle (-5 deg and 0 deg), (3) wing and forward-fuselage shape, and (4) nose shape of the fin-stabilizer juncture. A transonic symmetric-flutter boundary and flutter trends were established for variations in stabilizer pitch stiffness. Photographs of the test configurations are shown.

Ruhlin, C. L.; Sandford, M. C.

1975-01-01

356

Prediction of Downwash and Dynamic Pressure at the Tail from Free-flight Measurements  

NASA Technical Reports Server (NTRS)

The present measurements form a continuation of earlier flight tests published in a previous report for predicting the downwash at the tail of an airplane. The method makes use of the tail itself as integrating contact surface to the extent that, beginning from the measurement of the self-alignment of the elevator, the mean downwash angle and dynamic pressure at the tail are determined. The instrumental accuracy is considerably improved if the elevator is completely separate from the controls during the tests, because the effect of friction on the self-alignment of the elevator is then reduced to a minimum and a finer elevator weight balance is rendered possible. The structural design of the push-rod uncoupling mechanism is also described.

Eujen, E

1942-01-01

357

Ecological studies of the white-tailed deer in western Tennessee  

SciTech Connect

Activity patterns and microhabitat utilization of white-tailed deer (Odocoileus virginianus) are being studied at the Milan Army Ammunition Plant in Carroll and Gibson counties, Tennessee. Ten white-tailed deer have been fitted with radio-collars, and locations are being monitored using standard techniques. Home ranges and daily activity patterns are being determined. Preliminary analyses have shown that white-tailed deer are readily located using radio-techniques. Microhabitat utilization is being assessed by pellet transects and radio locations. Pellet counts from transects located in pastures and old fields are significantly different from those in other habitat types. Use of honeysuckle (Lonicera sp.) is being examined by observing the degree of browse along transects. No significant difference in utilization has been seen between the honeysuckle transects.

Frederick, R.D.; Kennedy, M.L. (Memphis State Univ., TN (United States))

1993-04-01

358

Atrophy and growth failure of rat hindlimb muscles in tail-cast suspension  

NASA Technical Reports Server (NTRS)

The primary objective of the present study is related to an evaluation of a modified tail-cast suspension model as a means of identifying metabolic factors which control or are associated with muscle atrophy and growth failure. Two different control conditions (normal and tail-casted weight bearing) were studied to determine the appropriate control for tail-cast suspension. A description is presented of a model which is most useful for studying atrophy of hindlimb muscles under certain conditions. Female Sprague-Dawley rats were employed in the experiments. Attention is given to growth rate and urinary excretion of urea and ammonia in different types of rats, the relationship between body weight and skeletal muscle weight, and the relationship between animal body weight and rates of protein synthesis and protein degradation.

Jaspers, S. R.; Tischler, M. E.

1984-01-01

359

Autotrophic Biofilm Development on Superficial Samples of the Gold–Silver Mine Tailings, Valenciana (Mexico): Pioneers in Tailings Remediation?  

Microsoft Academic Search

We report the results of long term bio-assays on microorganism colonization of mine tailings samples, taken from the Valenciana\\u000a mine tailings (Guanajuato, Mexico), under stable laboratory conditions (humidity, temperature, light exposure). In order to\\u000a identify the main metabolic groups of the potentially colonizing microorganisms and the implications of their growth on the\\u000a main tailing’s characteristics related to biological succession, organic

Jessica Viridiana García-Meza

2008-01-01

360

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

361

Wind-tunnel investigation at supersonic speeds of a remote-controlled canard missile with a free-rolling-tail brake torque system  

NASA Technical Reports Server (NTRS)

Wind tunnel tests were conducted at Mach numbers 1.70, 2.16, and 2.86 to determine the static aerodynamic characteristics of a cruciform canard-controlled missile with fixed or free rolling tailfin afterbodies. Mechanical coupling effects of the free-rolling-tail afterbody were investigated by using an electronic electromagnetic brake system providing arbitrary tail-fin brake torques with continuous measurements of tail-to-mainframe torque and tail roll rate. Remote-controlled canards were deflected to provide pitch, yaw, and roll control. Results indicate that the induced rolling moment coefficients due to canard yaw control are reduced and linearized for the free-rolling-tail (free-tail) configuration. The canards of the latter provide conventional roll control for the entire angle-of-attack test range. For the free-tail configuration, the induced rolling moment coefficient due to canard yaw control increased and the canard roll control decreased with increases in brake torque, which simulated bearing friction torque. It appears that a compromise in regard to bearing friction, for example, low-cost bearings with some friction, may allow satisfactory free-tail aerodynamic characteristics that include reductions in adverse rolling-moment coefficients and lower tail roll rates.

Blair, A. B., Jr.

1985-01-01

362

Manganese ore tailing: optimization of acid leaching conditions and recovery of soluble manganese.  

PubMed

Manganese recovery from industrial ore processing waste by means of leaching with sulfuric acid was the objective of this study. Experimental conditions were optimized by multivariate experimental design approaches. In order to study the factors affecting leaching, a screening step was used involving a full factorial design with central point for three variables in two levels (2(3)). The three variables studied were leaching time, concentration of sulfuric acid and sample amount. The three factors screened were shown to be relevant and therefore a Doehlert design was applied to determine the best working conditions for leaching and to build the response surface. By applying the best leaching conditions, the concentrations of 12.80 and 13.64 %w/w of manganese for the global sample and for the fraction -44 + 37 ?m, respectively, were found. Microbeads of chitosan were tested for removal of leachate acidity and recovering of soluble manganese. Manganese recovery from the leachate was 95.4%. Upon drying the leachate, a solid containing mostly manganese sulfate was obtained, showing that the proposed optimized method is efficient for manganese recovery from ore tailings. PMID:25284800

Santos, Olívia de Souza Heleno; Carvalho, Cornélio de Freitas; Silva, Gilmare Antônia da; Santos, Cláudio Gouvêa Dos

2015-01-01

363

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

364

Mass stranding of wedge-tailed shearwater chicks in Hawaii.  

PubMed

Unusual numbers of wedge-tailed shearwater (Puffinus pacificus) chicks stranded on Oahu (Hawaii, USA) in 1994. Compared to healthy wedge-tailed shearwater (WTSW) chicks, stranded chicks were underweight, dehydrated, leukopenic, lymphopenic, eosinopenic, and heterophilic; some birds were toxemic and septic. Stranded chicks also were hypoglycemic and had elevated aspartate amino transferase levels. Most chicks apparently died from emaciation, dehydration, or bacteremia. Because many birds with bacteremia also had severe necrosis of the gastrointestinal (GI) mucosa associated with bacteria, we suspect the GI tract to be the source of disseminated bacterial infection. The identity of the bacteria was not confirmed. The daily number of chicks stranded was significantly related to average wind speeds, and the mortality coincided with the fledging period for WTSW. Strong southeasterly winds were a distinguishing meteorologic factor in 1994 and contributed to the distribution of stranded chicks on Oahu. More objective data on WTSW demographics would enhance future efforts to determine predisposing causes of WTSW wrecks and their effects on seabird colonies. PMID:10479083

Work, T M; Rameyer, R A

1999-07-01

365

Mass stranding of wedge-tailed shearwater chicks in Hawaii  

USGS Publications Warehouse

Unusual numbers of wedge-tailed shearwater (Puffinus pacificus) chicks stranded on Oahu (Hawaii, USA) in 1994. Compared to healthy wedge-tailed shearwater (WTSW) chicks, stranded chicks were underweight, dehydrated, leukopenic, lymphopenic, eosinopenic, and heterophilic; some birds were toxemic and septic. Stranded chicks also were hypoglycemic and had elevated aspartate amino transferase levels. Most chicks apparently died from emaciation, dehydration, or bacteremia. Because many birds with bacteremia also had severe necrosis of the gastrointestinal (GI) mucosa associated with bacteria, we suspect the GI tract to be the source of disseminated bacterial infection. The identity of the bacteria was not confirmed. The daily number of chicks stranded was significantly related to average wind speeds, and the mortality coincided with the fledging period for WTSW. Strong southeasterly winds were a distinguishing meteorologic factor in 1994 and contributed to the distribution of stranded chicks on Oahu. More objective data on WTSW demographics would enhance future efforts to determine predisposing causes of WTSW wrecks and their effects on seabird colonies.

Work, T.M.; Rameyer, R.A.

1999-01-01

366

Do dwarf galaxies form in tidal tails?  

E-print Network

The formation of tidal dwarf galaxies (TDG) inside tidal arms of interacting disk galaxies has been studied with N-body and N-body/SPH simulations at different resolutions. In pure N-body simulations no bound objects are formed at high resolution. At low resolution bound objects can form in tidal tails in agreement with previous work. We conclude that tidal dwarf galaxies are not likely to form by pure collisionless collapse in tidal tails. However, the presence of a sufficiently massive and extended gas component in the progenitor disk supports the formation of bound stellar objects in the tidal arms. Our results clearly favor a dissipation supported scenario in which the formation of TDGs is induced by the local collapse of gas which then triggers the collapse of the stellar component.

M. Wetzstein; T. Naab; A. Burkert

2006-12-01

367

Novel tail and head group prostamide probes.  

PubMed

We report the design and synthesis of novel prostaglandin-ethanolamide (PGE2-EA) analogs containing head and tail group modifications to aid in the characterization of a putative prostamide receptor(s). Our synthetic approach utilizes Horner-Wadsworth-Emmons and Wittig reactions to construct the head and the tail moieties of the key PGE2 precursor, which leads to the final products through a peptide coupling, Swern oxidation and HF/pyridine assisted desilylation. The synthesized analogs were shown not to interact significantly with endocannabinoid proteins and recombinant EP1, EP3 and EP4 receptors and suggest a yet to be identified prostamide receptor as their site(s) of action. PMID:25701254

Finnegan, David F; Shelnut, Erin L; Nikas, Spyros P; Chiang, Nan; Serhan, Charles N; Makriyannis, Alexandros

2015-03-15

368

Baseline risk assessment for groundwater contamination at the uranium mill tailings site near Monument Valley, Arizona. Draft  

SciTech Connect

This baseline risk assessment evaluates potential impact to public health or the environment resulting from groundwater contamination at the former uranium mill processing site near Monument Valley, Arizona. The tailings and other contaminated material at this site are being relocated and stabilized in a disposal cell at Mexican Hat, Utah, through the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. The tailings removal is planned for completion by spring 1994. After the tailings are removed, groundwater contamination at the site will continue to be evaluated. This risk assessment is the first document specific to this site for the Groundwater Project. It will be used to assist in determining what remedial action is needed for contaminated groundwater at the site.

Not Available

1993-09-01

369

The C-terminal tail of protein kinase D2 and protein kinase D3 regulates their intracellular distribution  

SciTech Connect

We generated a set of GFP-tagged chimeras between protein kinase D2 (PKD2) and protein kinase D3 (PKD3) to examine in live cells the contribution of their C-terminal region to their intracellular localization. We found that the catalytic domain of PKD2 and PKD3 can localize to the nucleus when expressed without other kinase domains. However, when the C-terminal tail of PKD2 was added to its catalytic domain, the nuclear localization of the resulting protein was inhibited. In contrast, the nuclear localization of the CD of PKD3 was not inhibited by its C-terminal tail. Furthermore, the exchange of the C-terminal tail of PKD2 and PKD3 in the full-length proteins was sufficient to exchange their intracellular localization. Collectively, these data demonstrate that the short C-terminal tail of these kinases plays a critical role in determining their cytoplasmic/nuclear localization.

Papazyan, Romeo [Unit of Signal Transduction and Gastrointestinal Cancer, Division of Digestive Diseases, Department of Medicine, CURE Digestive Diseases Research Center and Molecular Biology Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles (United States); Rozengurt, Enrique [Unit of Signal Transduction and Gastrointestinal Cancer, Division of Digestive Diseases, Department of Medicine, CURE Digestive Diseases Research Center and Molecular Biology Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles (United States); Rey, Osvaldo [Unit of Signal Transduction and Gastrointestinal Cancer, Division of Digestive Diseases, Department of Medicine, CURE Digestive Diseases Research Center and Molecular Biology Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles (United States)]. E-mail: orey@mednet.ucla.edu

2006-04-14

370

Osteoprotegerin mitigates tail suspension-induced osteopenia  

Microsoft Academic Search

Osteoprotegerin (OPG) is a recently discovered protein related to the tumor necrosis factor receptor family. It has been shown to inhibit ovariectomy (ovx)-induced resorption in rats and increase bone mineral density in young mice. Tail suspension is a procedure that inhibits bone formation in maturing rodents. This study was designed to quantify OPG’s effect on cortical bone formation. Fifty-four mice

T. A. Bateman; C. R. Dunstan; V. L. Ferguson; D. L. Lacey; R. A. Ayers; S. J. Simske

2000-01-01

371

Tail Rotor Airfoils Stabilize Helicopters, Reduce Noise  

NASA Technical Reports Server (NTRS)

Founded by former Ames Research Center engineer Jim Van Horn, Van Horn Aviation of Tempe, Arizona, built upon a Langley Research Center airfoil design to create a high performance aftermarket tail rotor for the popular Bell 206 helicopter. The highly durable rotor has a lifetime twice that of the original equipment manufacturer blade, reduces noise by 40 percent, and displays enhanced performance at high altitudes. These improvements benefit helicopter performance for law enforcement, military training, wildfire and pipeline patrols, and emergency medical services.

2010-01-01

372

RED-TAILED HAWK (Buteo jamaicensis)  

Microsoft Academic Search

Daily fluctuations in resting heart rate (HR) were studied in a captive ? Red-tailed Hawk (Buteojamaicensis) using radiotelemetry. HR's were recorded hourly during 10 consecutive days while the hawk was housed in an outdoor pen. Daytime HR's averaged 202 beats\\/min and were significantly higher than the average nocturnal HR of 134 beats\\/min (P < 0.001). Maximum HR's ( >200 beats\\/min)

WILLIAM A. DEGRAw; N. C. CLAMPITT

373

Automated registration of tail bleeding in rats.  

PubMed

An automated system for registration of tail bleeding in rats using a camera and a user-designed PC-based software program has been developed. The live and processed images are displayed on the screen and are exported together with a text file for later statistical processing of the data allowing calculation of e.g. number of bleeding episodes, bleeding times and bleeding areas. Proof-of-principle was achieved when the camera captured the blood stream after infusion of rat whole blood into saline. Suitability was assessed by recording of bleeding profiles in heparin-treated rats, demonstrating that the system was able to capture on/off bleedings and that the data transfer and analysis were conducted successfully. Then, bleeding profiles were visually recorded by two independent observers simultaneously with the automated recordings after tail transection in untreated rats. Linear relationships were found in the number of bleedings, demonstrating, however, a statistically significant difference in the recording of bleeding episodes between observers. Also, the bleeding time was longer for visual compared to automated recording. No correlation was found between blood loss and bleeding time in untreated rats, but in heparinized rats a correlation was suggested. Finally, the blood loss correlated with the automated recording of bleeding area. In conclusion, the automated system has proven suitable for replacing visual recordings of tail bleedings in rats. Inter-observer differences can be eliminated, monotonous repetitive work avoided, and a higher through-put of animals in less time achieved. The automated system will lead to an increased understanding of the nature of bleeding following tail transection in different rodent models. PMID:18449428

Johansen, Peter B; Henriksen, Lars; Andresen, Per R; Lauritzen, Brian; Jensen, Kåre L; Juhl, Trine N; Tranholm, Mikael

2008-05-01

374

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

375

The Sulften System - Advanced tail gas treating  

SciTech Connect

The Sulften System is an advanced tail gas treating process that maximizes sulfur recovery efficiency by the combination of new and unique reaction and absorption technologies. The principal feature of the Sulften System is its ability to produce a sulfur plant vent gas effluent with a hydrogen sulfide (H/sub 2/S) concentration of less than 10 ppm on a dry and oxygen-free basis. Conventional tail gas treating processes typically produce a vent stream containing 100 to 250 ppm H/sub 2/S. The primary goal of the Sulften System is to meet the U.S. Environmental Protection Agency New Source Performance Standards (NSPS) requirement that direct discharge of H/sub 2/S be limited to concentrations of less than 10 ppm. The resultant benefits of this technological breakthrough are a reduction in total sulfur discharge and incinerator thermal pollution, virtual elimination of incinerator fuel cost, reduction in tail gas treating unit (TGTU) operating cost, and potential reduction in incinerator capital investment for a grassroots unit, while providing the operating ease characteristic of amine-based TGTU processes.

Kroop, L.; Sigmund, P.W.; Taggart, G.W.

1985-01-01

376

Active Vertical Tail Buffeting Alleviation on a Twin-Tail Fighter Configuration in a Wind Tunnel  

NASA Technical Reports Server (NTRS)

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 tail was equipped with piezoelectric actuators. The tunnel conditions were atmospheric air at a dynamic pressure of 14 psf. By using single-input-single-output control laws at gains well below the physical limits of the control effectors, the power spectral density of the root strains at the frequency of the first bending mode of the vertical tail was reduced by as much as 60 percent up to angles of attack of 37 degrees. Root mean square (RMS) values of root strain were reduced by as much as 19 percent. Stability margins indicate that a constant gain setting in the control law may be used throughout the range of angle of attack tested.

Moses, Robert W.

1997-01-01

377

Baseline risk assessment of ground water contamination at the uranium mill tailings site near Canonsburg, Pennsylvania. Revision 1  

SciTech Connect

For the UMTRA Project site located near Canonsburg, Pennsylvania (the Canonsburg site), the Surface Project cleanup occurred from 1983 to 1985, and involved removing the uranium processing mill tailings and radioactively contaminated soils and materials from their original locations and placing them in a disposal cell located on the former Canonsburg uranium mill site. This disposal cell is designed to minimize radiation emissions and further contamination of ground water beneath the site. The Ground Water Project will evaluate the nature and the extent of ground water contamination resulting from uranium processing at the former Canonsburg uranium mill site, and will determine a ground water strategy for complying with the US Environmental Protection Agency`s (EPA) ground water standards established for the UMTRA Project. For the Canonsburg site, an evaluation was made to determine whether exposure to ground water contaminated by uranium processing could affect people`s health. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Canonsburg site. The results of this report and further site characterization of the Canonsburg site will be used to determine how to protect public health and the environment, and how to comply with the EPA standards.

NONE

1995-11-01

378

Citizen knowledge and perception of black-tailed prairie dog management; report to respondents  

USGS Publications Warehouse

In the late summer of 2000, we canvassed a random sample of residents in the 11-state short grass prairie region of the United States. We asked about peoplea??s attitude toward and knowledge of black-tailed prairie dogs and their management. The survey received 1,933 useable responses with a response rate of 56.4% (margin of error +/- 2.2%). We developed a questionnaire (OMB Control Number: 1028-0073; see Appendix B) to answer the following questions: * What is the level of citizen knowledge regarding black-tailed prairie dogs? * What are citizensa?? attitudes and preferences regarding black-tailed prairie dogs and the environment in general? * What are the factors that explain difference in attitudes and knowledge about prairie dogs? * What are the factors that explain citizen participation in these types of issues? * What are the important differences between rural and urban citizens regarding their political participation and their knowledge and attitudes about prairie dogs? In general, we found that citizens do not have a high regard for black-tailed prairie dogs. Citizens generally have a positive orientation toward the environment and favor a balanced or somewhat environmental approach on questions--like prairie dog management--that involve environmental protection and economic considerations. People having direct experience with prairie dogs specifically, most citizens did not believe the question of what to do about these animals was a highly important environmental issue.

Sexton, N.R.; Brinson, Ayeisha; Ponds, P.D.; Cline, Kurt

2001-01-01

379

Changes in zinc speciation with mine tailings acidification in a semi-arid weathering environment  

PubMed Central

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 semi-arid 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 surficial tailings samples from the Klondyke State Superfund Site (AZ, USA), ranging in pH from 5.4 to 2.6, represent a weathering series, with acidification resulting from sulfide mineral oxidation, long-term Fe hydrolysis, and a concurrent decrease in total (6,000 to 450 mg kg?1) and plant-available (590 to 75 mg kg?1) Zn due to leaching losses and changes in Zn speciation. Here, we used bulk and micro-focused Zn K-edge X-ray absorption spectroscopy (XAS) data and a six-step sequential extraction procedure to determine tailings solid phase Zn speciation. Bulk sample spectra were fit by linear combination using three references: Zn-rich phyllosilicate (Zn0.8talc), Zn sorbed to ferrihydrite (ZnadsFeOx), and zinc sulfate (ZnSO4·7H2O). Analyses indicate that Zn sorbed in tetrahedral coordination to poorly-crystalline Fe and Mn (oxyhydr)oxides decreases with acidification in the weathering sequence, whereas octahedral zinc in sulfate minerals and crystalline Fe oxides undergoes a relative accumulation. Micro-scale analyses identified hetaerolite (ZnMn2O4), hemimorphite (Zn4Si2O7(OH)2·H2O) and sphalerite (ZnS) as minor phases. Bulk and micro-focused spectroscopy complement the chemical extraction results and highlight the importance of using a multi-method approach to interrogate complex tailings systems. PMID:21761897

Hayes, Sarah M.; O’Day, Peggy A.; Webb, Sam M.; Maier, Raina M.; Chorover, Jon

2011-01-01

380

Using soil island plantings as dispersal vectors in large area copper tailings reforestation  

SciTech Connect

The Wenatchee National Forest undertook the reforestation of the 80 acre (35 ha) Holden copper mine tailings of Washington State in 1989 by using 20, one-fourth acre, triangular shaped soil islands as a source of plant propagules targeted for gravel-covered tailings surfaces. The islands were constructed of soil and surface litter transported from a nearby gravel pit, and planted with four species of conifer seedlings, the shrub Sitka alder (Alnus sinuata) and eight species of grasses. Conifer and alder seedlings were also planted in graveled covered tailings with amendments. Since reproductive status of the conifers would not occur for several years, this propagule vector hypothesis was tested by measuring the distances traveled onto the tailings surface by grass seeds. The number of grass shoots established in four treatment blocks in target plots downwind from the soil island source plantings was also determined. After 36 months, grass seed had migrated to a distance of 32 feet (11 m) from the soil island source. Grass shoots were present within 10 feet (3 m) downwind of the soil island, the most frequent being Mountain brome (Bromus marginatus). Among the tree species, lodgepole pine (Pinus contorta) and Sitka alder grew an average of 6 inches (15--16 cm) after 40 months on the soil islands but somewhat less on the tailing surface. By the third growing season, the only tree species in reproductive condition on the tailings was alder. The soil-island technique is successful for grass dispersal and may have potential for conifer and alder migration.

Scherer, G.; Everett, R. [Dept. of Agriculture, Wenatchee, WA (United States). Forestry Science Lab.

1998-12-31

381

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

382

Quantitative Microbial Community Analysis of Three Different Sulfidic Mine Tailing Dumps Generating Acid Mine Drainage?  

PubMed Central

The microbial communities of three different sulfidic and acidic mine waste tailing dumps located in Botswana, Germany, and Sweden were quantitatively analyzed using quantitative real-time PCR (Q-PCR), fluorescence in situ hybridization (FISH), catalyzed reporter deposition-FISH (CARD-FISH), Sybr green II direct counting, and the most probable number (MPN) cultivation technique. Depth profiles of cell numbers showed that the compositions of the microbial communities are greatly different at the three sites and also strongly varied between zones of oxidized and unoxidized tailings. Maximum cell numbers of up to 109 cells g?1 dry weight were determined in the pyrite or pyrrhotite oxidation zones, whereas cell numbers in unoxidized tailings were significantly lower. Bacteria dominated over Archaea and Eukarya at all tailing sites. The acidophilic Fe(II)- and/or sulfur-oxidizing Acidithiobacillus spp. dominated over the acidophilic Fe(II)-oxidizing Leptospirillum spp. among the Bacteria at two sites. The two genera were equally abundant at the third site. The acidophilic Fe(II)- and sulfur-oxidizing Sulfobacillus spp. were generally less abundant. The acidophilic Fe(III)-reducing Acidiphilium spp. could be found at only one site. The neutrophilic Fe(III)-reducing Geobacteraceae as well as the dsrA gene of sulfate reducers were quantifiable at all three sites. FISH analysis provided reliable data only for tailing zones with high microbial activity, whereas CARD-FISH, Q-PCR, Sybr green II staining, and MPN were suitable methods for a quantitative microbial community analysis of tailings in general. PMID:18586975

Kock, Dagmar; Schippers, Axel

2008-01-01

383

An adenovirus linked to mortality and disease in long-tailed ducks (Clangula hyemalis) in Alaska  

USGS Publications Warehouse

An adenovirus was isolated from intestinal samples of two long-tailed ducks (Clangula hyemalis) collected during a die-off in the Beaufort Sea off the north coast of Alaska in 2000. The virus was not neutralized by reference antiserum against known group I, II, or III avian adenoviruses and may represent a new serotype. The prevalence of the virus was determined in live-trapped long-tailed ducks at the mortality site and at a reference site 100 km away where no mortality was observed. Prevalence of adenovirus antibodies in serum samples at the mortality site was 86% compared to 10% at the reference site. Furthermore, 50% of cloacal swabs collected at the mortality site and only 7% of swabs from the reference site were positive for adenoviruses. In 2001, no mortality was observed at either of the study areas, and virus prevalence in both serum and cloacal samples was low, providing further evidence that the adenovirus was linked to the mortality event in 2000. The virus was used to infect long-tailed ducks under experimental conditions and resulted in lesions previously described for avian adenovirus infections and similar to those observed in long-tailed duck carcasses from the Beaufort Sea. The status of long-tailed ducks has recently become a concern in Alaska due to precipitous declines in breeding populations there since the mid-1970s. Our findings suggest that the newly isolated adenovirus is a disease agent and source of mortality in long-tailed ducks, and thus could be a contributing factor in population declines.

Hollmen, T.E.; Franson, J.C.; Flint, P.L.; Grand, J.B.; Lanctot, Richard B.; Docherty, D.E.; Wilson, H.M.

2003-01-01

384

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 surficial tailings samples from the Klondyke State Superfund Site (AZ, USA), ranging in pH from 5.4 to 2.6, represent a weathering series, with acidification resulting from sulfide mineral oxidation, long-term Fe hydrolysis, and a concurrent decrease in total (6000 to 450 mg kg{sup -1}) and plant-available (590 to 75 mg kg{sup -1}) Zn due to leaching losses and changes in Zn speciation. Here, we used bulk and microfocused Zn K-edge X-ray absorption spectroscopy (XAS) data and a six-step sequential extraction procedure to determine tailings solid phase Zn speciation. Bulk sample spectra were fit by linear combination using three references: Zn-rich phyllosilicate (Zn{sub 0.8}talc), Zn sorbed to ferrihydrite (Zn{sub adsFeOx}), and zinc sulfate (ZnSO{sub 4} {center_dot} 7H{sub 2}O). Analyses indicate that Zn sorbed in tetrahedral coordination to poorly crystalline Fe and Mn (oxyhydr)oxides decreases with acidification in the weathering sequence, whereas octahedral zinc in sulfate minerals and crystalline Fe oxides undergoes a relative accumulation. Microscale analyses identified hetaerolite (ZnMn{sub 2}O{sub 4}), hemimorphite (Zn{sub 4}Si{sub 2}O{sub 7}(OH){sub 2} {center_dot} H{sub 2}O) and sphalerite (ZnS) as minor phases. Bulk and microfocused spectroscopy complement the chemical extraction results and highlight the importance of using a multimethod approach to interrogate complex tailings systems.

Hayes, Sarah M.; O’ Day, Peggy A.; Webb, Sam M.; Maier, Raina M.; Chorover, Jon (UCM); (SLAC); (Ariz)

2012-10-09

385

Quantitative microbial community analysis of three different sulfidic mine tailing dumps generating acid mine drainage.  

PubMed

The microbial communities of three different sulfidic and acidic mine waste tailing dumps located in Botswana, Germany, and Sweden were quantitatively analyzed using quantitative real-time PCR (Q-PCR), fluorescence in situ hybridization (FISH), catalyzed reporter deposition-FISH (CARD-FISH), Sybr green II direct counting, and the most probable number (MPN) cultivation technique. Depth profiles of cell numbers showed that the compositions of the microbial communities are greatly different at the three sites and also strongly varied between zones of oxidized and unoxidized tailings. Maximum cell numbers of up to 10(9) cells g(-1) dry weight were determined in the pyrite or pyrrhotite oxidation zones, whereas cell numbers in unoxidized tailings were significantly lower. Bacteria dominated over Archaea and Eukarya at all tailing sites. The acidophilic Fe(II)- and/or sulfur-oxidizing Acidithiobacillus spp. dominated over the acidophilic Fe(II)-oxidizing Leptospirillum spp. among the Bacteria at two sites. The two genera were equally abundant at the third site. The acidophilic Fe(II)- and sulfur-oxidizing Sulfobacillus spp. were generally less abundant. The acidophilic Fe(III)-reducing Acidiphilium spp. could be found at only one site. The neutrophilic Fe(III)-reducing Geobacteraceae as well as the dsrA gene of sulfate reducers were quantifiable at all three sites. FISH analysis provided reliable data only for tailing zones with high microbial activity, whereas CARD-FISH, Q-PCR, Sybr green II staining, and MPN were suitable methods for a quantitative microbial community analysis of tailings in general. PMID:18586975

Kock, Dagmar; Schippers, Axel

2008-08-01

386

Coplanar tail-chase aerial combat as a differential game  

NASA Technical Reports Server (NTRS)

A reduced-order version of the one-on-one aerial combat problem is studied as a pursuit-evasion differential game. The coplanar motion takes place at given speeds and given maximum available turn rates, and is described by three state equations which are equivalent to the range, bearing, and heading of one aircraft relative to the other. The purpose of the study is to determine those relative geometries from which either aircraft can be guaranteed a win, regardless of the maneuver strategies of the other. Termination is specified by the tail-chase geometry, at which time the roles of pursuer and evader are known. The roles are found in general, together with the associated optimal turn maneuvers, by solution of the differential game of kind. For the numerical parameters chosen, neither aircraft can win from the majority of possible initial conditions if the other turns optimally in certain critical geometries.

Merz, A. W.; Hague, D. S.

1977-01-01

387

Serum 25-Hydroxvitamin D Concentrations in Captive and Free-Ranging, White-Tailed Deer (Odocoileus virginianus)  

Technology Transfer Automated Retrieval System (TEKTRAN)

ABSTRACT: Serum concentrations of 25-hydroxyvitamin D [25(OH)D] were determined for free-ranging and captive white-tailed deer (WTD, Odocoileus virginianus). Effects of gender, season, and age on 25(OH)D concentrations were determined as well as comparisons to concentrations in serum from captive re...

388

Analyses of trace elements on quartz surfaces in sulfidic mine tailings from Kristineberg (Sweden) a few years after remediation  

Microsoft Academic Search

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been applied to determine the elemental composition of the surface layer, as well as of the first interior layer, of quartz grains from the mine tailings from Kristineberg (northern Sweden) in order to determine concentration gradients between these two layers. The quartz grains were collected from the oxidized and unoxidized zones

B. Müller; M. D. Axelsson; B. Öhlander

2003-01-01

389

DOE/EIS-0355 Remediation of the Moab Uranium Mill Tailings, Grand and San Juan Counties, Utah, Final Environmental Impact Statement (July 2005)  

SciTech Connect

The U.S. Department of Energy (DOE or the Department) is proposing to clean up surface contamination and implement a ground water compliance strategy to address contamination that resulted from historical uranium-ore processing at the Moab Uranium Mill Tailings Site (Moab site), Grand County, Utah. Pursuant to the National Environmental Policy Act (NEPA), 42 United States Code (U.S.C.) {section} 4321 et seq., DOE prepared this environmental impact statement (EIS) to assess the potential environmental impacts of remediating the Moab site and vicinity properties (properties where uranium mill tailings were used as construction or fill material before the potential hazards associated with the tailings were known). DOE analyzed the potential environmental impacts of both on-site and off-site remediation and disposal alternatives involving both surface and ground water contamination. DOE also analyzed the No Action alternative as required by NEPA implementing regulations promulgated by the Council on Environmental Quality. DOE has determined that its preferred alternatives are the off-site disposal of the Moab uranium mill tailings pile, combined with active ground water remediation at the Moab site. The preferred off-site disposal location is the Crescent Junction site, and the preferred method of transportation is rail. The basis for this determination is discussed later in this Summary. DOE has entered into agreements with 12 federal, tribal, state, and local agencies to be cooperating agencies in the development and preparation of this EIS. Several of the cooperating agencies have jurisdiction by law and intend to use the EIS to support their own decisionmaking. The others have expertise relevant to potential environmental, social, or economic impacts within their geographic regions. During the preparation of the EIS, DOE met with the cooperating agencies, provided them with opportunities to review preliminary versions of the document, and addressed their comments and concerns to the fullest extent possible. DOE received over 1,600 comments on the draft EIS from the public, federal, state and local agencies, tribes, governors, and members of Congress. DOE has considered these comments in finalizing the EIS and has provided responses to all comments in the EIS.

N /A

2005-08-05

390

Pain-Suppressed Behaviors in the Red-tailed Hawk 1 (Buteo jamaicensis)  

PubMed Central

Our ability to provide analgesia in wild and exotic patients is hampered by a lack of species-specific information on effective drugs and protocols. One contributing factor is the difficulty of applying data from traditional laboratory tests of nociception to clinical conditions frequently involving combinations of inflammatory, mechanical, and neuropathic pain. Pain-suppressed behaviors have become a valuable predictor of clinical utility in other species; in this study we extend this framework to red -tailed hawks in a wildlife hospital, in an attempt to develop a new, humane testing method for birds of prey. We scored six behaviors in hawks hospitalized either for orthopedic trauma or for non-painful conditions. These behaviors included: movement about the cage, grooming, head motions, foot shifts, beak clacks, and rouse. Movement, head motions, and beak clacks were all significantly reduced in hawks with recent orthopedic injury, but not in hawks with healed or minor injuries (P<0.05 for all behaviors). However, it should be noted that due to stringent admission criteria, and the difficulties inherent in studying naturally-occuring injury in wild patients, this study only included -subjects in four experimental groups, and this limited our ability to fully investigate confounds within our data. A follow-up experiment was conducted to determine potential effects of buprenorphine, a mu opioid agonist, on the behaviors listed above. Buprenorphine in the absence of pain caused minor, non-significant decreases in most behaviors, and had no effect on head movement frequency. This suggests that head movements in particular may be sensitive to pain but not to sedative side-effects of buprenorphine. Overall, red -tailed hawks with recent orthopedic trauma show consistent and marked red uctions in several normal maintenance behaviors. Head movements, reported for the first time in this study as a potential marker of pain in birds, in particular seem to be insensitive to sedative side effects of buprenorphine, while being a sensitive measu re of affective state in hawks with painful injuries. These behaviors can be scored humanely and with minimal expense, and should be considered for further research on pain and analgesia in avian species. PMID:24904190

Mazor-Thomas, Jana E.; Mann, Phyllis E.; Karas, Alicia Z.; Tseng, Flo

2014-01-01

391

Pain-Suppressed Behaviors in the Red-tailed Hawk 1 (Buteo jamaicensis).  

PubMed

Our ability to provide analgesia in wild and exotic patients is hampered by a lack of species-specific information on effective drugs and protocols. One contributing factor is the difficulty of applying data from traditional laboratory tests of nociception to clinical conditions frequently involving combinations of inflammatory, mechanical, and neuropathic pain. Pain-suppressed behaviors have become a valuable predictor of clinical utility in other species; in this study we extend this framework to red -tailed hawks in a wildlife hospital, in an attempt to develop a new, humane testing method for birds of prey. We scored six behaviors in hawks hospitalized either for orthopedic trauma or for non-painful conditions. These behaviors included: movement about the cage, grooming, head motions, foot shifts, beak clacks, and rouse. Movement, head motions, and beak clacks were all significantly reduced in hawks with recent orthopedic injury, but not in hawks with healed or minor injuries (P<0.05 for all behaviors). However, it should be noted that due to stringent admission criteria, and the difficulties inherent in studying naturally-occuring injury in wild patients, this study only included -subjects in four experimental groups, and this limited our ability to fully investigate confounds within our data. A follow-up experiment was conducted to determine potential effects of buprenorphine, a mu opioid agonist, on the behaviors listed above. Buprenorphine in the absence of pain caused minor, non-significant decreases in most behaviors, and had no effect on head movement frequency. This suggests that head movements in particular may be sensitive to pain but not to sedative side-effects of buprenorphine. Overall, red -tailed hawks with recent orthopedic trauma show consistent and marked red uctions in several normal maintenance behaviors. Head movements, reported for the first time in this study as a potential marker of pain in birds, in particular seem to be insensitive to sedative side effects of buprenorphine, while being a sensitive measu re of affective state in hawks with painful injuries. These behaviors can be scored humanely and with minimal expense, and should be considered for further research on pain and analgesia in avian species. PMID:24904190

Mazor-Thomas, Jana E; Mann, Phyllis E; Karas, Alicia Z; Tseng, Flo

2014-03-01

392

The PHD Finger of Human UHRF1 Reveals a New Subgroup of Unmethylated Histone H3 Tail Readers  

PubMed Central

The human UHRF1 protein (ubiquitin-like containing PHD and RING finger domains 1) has emerged as a potential cancer target due to its implication in cell cycle regulation, maintenance of DNA methylation after replication and heterochromatin formation. UHRF1 functions as an adaptor protein that binds to histones and recruits histone modifying enzymes, like HDAC1 or G9a, which exert their action on chromatin. In this work, we show the binding specificity of the PHD finger of human UHRF1 (huUHRF1-PHD) towards unmodified histone H3 N-terminal tail using native gel electrophoresis and isothermal titration calorimetry. We report the molecular basis of this interaction by determining the crystal structure of huUHRF1-PHD in complex with the histone H3 N-terminal tail. The structure reveals a new mode of histone recognition involving an extra conserved zinc finger preceding the conventional PHD finger region. This additional zinc finger forms part of a large surface cavity that accommodates the side chain of the histone H3 lysine K4 (H3K4) regardless of its methylation state. Mutation of Q330, which specifically interacts with H3K4, to alanine has no effect on the binding, suggesting a loose interaction between huUHRF1-PHD and H3K4. On the other hand, the recognition appears to rely on histone H3R2, which fits snugly into a groove on the protein and makes tight interactions with the conserved aspartates D334 and D337. Indeed, a mutation of the former aspartate disrupts the formation of the complex, while mutating the latter decreases the binding affinity nine-fold. PMID:22096602

Lallous, Nada; Legrand, Pierre; McEwen, Alastair G.; Ramón-Maiques, Santiago; Samama, Jean-Pierre; Birck, Catherine

2011-01-01

393

Characterization of five subgroups of the sieve element occlusion gene family in Glycine max reveals genes encoding non-forisome P-proteins, forisomes and forisome tails.  

PubMed

P-proteins are structural phloem proteins discussed to be involved in the rapid sealing of injured sieve elements. P-proteins are found in all dicotyledonous and some monocotyledonous plants, but additional crystalloid P-proteins, known as forisomes, have evolved solely in the Fabaceae. Both types are encoded by members of the sieve element occlusion (SEO) gene family, which comprises seven phylogenetic subgroups. The Fabaceae-specific subgroup 1 contains genes encoding forisome subunits in e.g. Medicago truncatula, Vicia faba, Dipteryx panamensis and Canavalia gladiata whereas basal subgroup 5 encodes P-proteins in Nicotiana tabacum (tobacco) and Arabidopsis thaliana. The function of remaining subgroups is still unknown. We chose Glycine max (soybean) as a model to investigate SEO proteins representing different subgroups in one species. We isolated native P-proteins to determine the SEO protein composition and analyzed the expression pattern, localization and structure of the G. max SEO proteins representing five of the subgroups. We found that subgroup 1 GmSEO genes encode forisome subunits, a member of subgroup 5 encodes a non-forisome P-protein and subgroup 2 GmSEO genes encode the components of forisome tails, which are present in a restricted selection of Fabaceaen species. We therefore present the first molecular characterization of a Fabaceae non-forisome P-protein and the first evidence that forisome tails are encoded by a phylogenetically-distinct branch of the SEO gene family. PMID:24928491

Zielonka, Sascia; Ernst, Antonia M; Hawat, Susan; Twyman, Richard M; Prüfer, Dirk; Noll, Gundula A

2014-09-01

394

The Tail of Integrins, Talin, and Kindlins  

NSDL National Science Digital Library

Integrins are transmembrane cellâ??adhesion molecules that carry signals from the outside to the inside of the cell and vice versa. Like other cell surface receptors, integrins signal in response to ligand binding; however, events within the cell can also regulate the affinity of integrins for ligands. This feature is important in physiological situations such as those in blood, in which cells are always in close proximity to their ligands, yet cell-ligand interactions occur only after integrin activation in response to specific external cues. This review focuses on the mechanisms whereby two key proteins, talin and the kindlins, regulate integrin activation by binding the tails of integrin-β subunits.

Markus Moser (Max Planck Institute of Biochemistry; )

2009-05-15

395

Plasma flow pulsations in earth's magnetic tail  

NASA Technical Reports Server (NTRS)

On November 9, 1972 Imp 7 was in the plasma sheet from 0430 to 1000 UT and detected strong earthward plasma flows. A series of nine temporal pulsations were observed to vary in bulk speed from 0 to about 1500 km/s and to occur at 15-30 minute intervals. A positive correlation exists between the speed variations and changes in the standard deviation of the magnetic field. Evident periodicity was not found corresponding to Imp 7 pulsations and other magnetospheric or solar wind data. It is felt that the pulsations may indicate that tail reconnection is unsteady in periods of 10-30 minutes.

Coroniti, F. V.; Frank, L. A.; Ackerson, K. L.; Lepping, R. P.; Scarf, F. L.

1978-01-01

396

The Damping Tail of CMB Anisotropies  

E-print Network

By decomposing the damping tail of CMB anisotropies into a series of transfer functions representing individual physical effects, we provide ingredients that will aid in the reconstruction of the cosmological model from small-scale CMB anisotropy data. We accurately calibrate the model-independent effects of diffusion and reionization damping which provide potentially the most robust information on the background cosmology. Removing these effects, we uncover model-dependent processes such as the acoustic peak modulation and gravitational enhancement that can help distinguish between alternate models of structure formation and provide windows into the evolution of fluctuations at various stages in their growth.

Wayne Hu; Martin White

1996-09-10

397

Aerodynamic characteristics of horizontal tail surfaces  

NASA Technical Reports Server (NTRS)

Collected data are presented on the aerodynamic characteristics of 17 horizontal tail surfaces including several with balanced elevators and two with end plates. Curves are given for coefficients of normal force, drag, and elevator hinge moment. A limited analysis of the results has been made. The normal-force coefficients are in better agreement with the lifting-surface theory of Prandtl and Blenk for airfoils of low aspect ratio than with the usual lifting-line theory. Only partial agreement exists between the elevator hinge-moment coefficients and those predicted by Glauert's thin-airfoil theory.

Silverstein, Abe; Katzoff, S

1940-01-01

398

Altitude-wind-tunnel investigation of tail-pipe burning with a Westinghouse X24C-4B axial-flow turbojet engine  

NASA Technical Reports Server (NTRS)

Thrust augmentation of an axial-flow type turbojet engine by burning fuel in the tail pipe has been investigated in the NACA Cleveland altitude wind tunnel. The performance was determined over a range of simulated flight conditions and tail-pipe fuel flows. The engine tail pipe was modified for the investigation to reduce the gas velocity at the inlet of the tail-pipe combustion chamber and to provide an adequate seat for the flame; four such modifications were investigated. The highest net-thrust increase obtained in the investigation was 86 percent with a net thrust specific fuel consumption of 2.91 and a total fuel-air ratio of 0.0523. The highest combustion efficiencies obtained with the four configurations ranged from 0.71 to 0.96. With three of the tail-pipe burners, for which no external cooling was provided, the exhaust nozzle and the rear part of the burner section were bright red during operation at high tail-pipe fuel-air ratios. With the tail-pipe burner for which fuel and water cooling were provided, the outer shell of the tail-pipe burner showed no evidence of elevated temperatures at any operating condition.

Fleming, William A; Wallner, Lewis E

1948-01-01

399

Flight Measurements of Horizontal-Tail Loads on the Bell X-5 Research Airplane at a Sweep Angle of 58.7 Deg  

NASA Technical Reports Server (NTRS)

A flight investigation was made at altitudes of 40,000, 25,000 and 15,000 feet to determine the horizontal-tail loads of the Bell X-5 research airplane at a sweep angle of 58.7 deg over the lift range of the airplane for Mach numbers from 0.61 to 1.00. The horizontal-tail loads were found to be nonlinear with lift throughout the lift ranges tested at all Mach numbers except at a Mach number of 1.00. The balancing tail loads reflected the changes which occur in the wing characteristics with increasing angle of attack. The nonlinearities were, in general, more pronounced at the higher angles of attack near the pitch-up where the balancing tail loads indicate that the wing-fuselage combination becomes unstable. No apparent effects of altitude on the balancing tail loads were evident over the comparable lift ranges of these tests at altitudes from 40,000 feet to 15,000 feet. Comparisons of balancing tail loads obtained from flight and windtunnel tests indicated discrepancies in absolute magnitudes, but the general trends of the data agree. Some differences in absolute magnitude may be accounted for by the tail load carried inboard of the strain-gage station and the load induced on the fuselage by the presence of the tail. These loads were not measured in flight.

Reed, Robert D

1955-01-01

400

On Tail Index Estimation Using Dependent,Heterogenous Data  

Microsoft Academic Search

In this paper we analyze the asymptotic properties of the popularly used distribution tail estimator by B. Hill (1975), for heavy-tailed heterogenous, dependent processes. We prove the Hill estimator is weakly consistent for functionals of mixingales and L1-approximable processes with regularly varying tails, covering ARMA, GARCH, and many IGARCH and FIGARCH processes. Moreover, for functionals of processes near epoch-dependent on

Jonathan B. Hill

2005-01-01

401

Review of fugitive dust control for uranium mill tailings  

SciTech Connect

An immediate concern associated with the disposal of uranium mill tailings is that wind erosion of the tailings from an impoundment area will subsequently deposit tailings on surrounding areas. Pacific Northwest Laboratory (PNL), under contract to the U.S. Nuclear Regulatory Commission, is investigating the current technology for fugitive dust control. Different methods of fugitive dust control, including chemical, physical, and vegetative, have been used or tested on mill tailings piles. This report presents the results of a literature review and discussions with manufacturers and users of available stabilization materials and techniques.

Li, C.T.; Elmore, M.R.; Hartley, J.N.

1983-01-01

402

Sorption of copper by vegetated copper-mine tailings  

NASA Astrophysics Data System (ADS)

The lixiviation of copper (Cu) from vegetated mine tailings may present an environmental risk because of the potential adverse effects it may pose to ground and surface water around mines. However, bonding of Cu to mine tailings can limit transfer to surrounding water. The main objective of the present study is to assess Cu sorption by cultivated Cu-mine tailings containing calcite (pH 7.7) as influenced by commercial peat moss-shrimp waste compost (PSC) and chelating solution. Fresh tailing and tailing that had been used in pot experiments were tested and compared. Samples (0.50 g) of tailings were equilibrated with 20 cm3 of 0.01 M CaCl2 solution containing 100 mg Cu dm-3, as CuCl2, for 72 h at room temperature. After equilibration period, the samples were centrifuged and filtered. Concentration of Cu in the equilibrium solution was measured by atomic absorption spectrophotometry. The sorption coefficient (Ks) was used to interpret the sorption data. The sorption experiment was replicated two times. Compost was the most effective organic amendment in enhancing Cu sorption. The Ks values were positively and significantly correlated with organic matter content and Cu associated with the organic fraction of tailing samples. The mineralogy and organic matter content can influence the sorption capacity of Cu-mine tailings. Calcite-containing mine tailings amended with PSC can be used to sorb Cu from chloride solutions.

de Coninck, A.; Karam, A.; Jaouich, A.

2009-04-01

403

Research Article Survival of White-Tailed Deer Neonates  

E-print Network

, landscape, Minnesota, mortality, neonate, Odocoileus virginianus, predation, South Dakota, survival. Understanding white-tailed deer (Odocoileus virginianus) population dynamics requires knowledge of survival

404

Exploring Stellar Populations in the Tidal Tails of NGC3256  

NASA Astrophysics Data System (ADS)

Galaxy interactions can inject material into the intergalactic medium via violent gravitational dynamics, often visualized in tidal tails. The composition of these tails has remained a mystery, as previous studies have focused on detecting tidal features, rather than the composite material itself. With this in mind, we have developed an observing program using deep, multiband imaging to probe the chaotic regions of tidal tails in search for an underlying stellar population. NGC3256's Western and Eastern tidal tails serve as a case study for this new technique. Our results show median color values of u - g = 1.12 and r - i = 0.09 for the Western tail, and u - g = 1.29 and r - i = 0.21 for the Eastern tail, corresponding to ages of approximately 450 Myr and 900 Myr for the tails, respectively. A u - g color gradient is seen in the Western tail as well, running from 1.32 to 1.08 (~2000 Myr to 400 Myr), suggesting ages inside tidal tails can have significant variations.

Rodruck, Michael; Konstantopoulos, Iraklis; Charlton, Jane C.

2015-01-01

405

Evaluating target cold spots by the use of tail EUDs *†  

PubMed Central

Purpose To propose a new measure of target underdose that can be used in the evaluation and optimization of radiotherapy dose distributions. Methods and Materials We compare various formulations of the equivalent uniform dose (EUD) and introduce a modification of existing EUD definitions, which we call tail EUD. Tail EUD is a measure of “cold spots” below the prescription dose in the target dose distribution. It has units of Gy. We investigate the mathematical properties of various target EUD concepts, including tail EUD. We apply the tail EUD measure retrospectively to intensity modulated radiation therapy (IMRT) treatment plans from our plan database. We also use tail EUD as an optimization objective in the optimization of prostate, pancreas, and head&neck plans. Results Tail EUD has desirable mathematical properties. In particular, it is convex and it leads to convex level sets (i.e., no local minima) if the EUD from which it is derived is concave. The tail EUD value is correlated with the subjective degree of target coverage. Constraining tail EUDs to a certain level in plan optimization leads to comparable target coverage in different plans and treatment sites. Conclusions The newly introduced concept of tail EUD appears to be useful both for plan evaluation and optimization. In addition, it can potentially be applied in the design of new clinical protocols. PMID:18440728

Bortfeld, Thomas; Craft, David; Dempsey, James F.; Halabi, Tarek; Romeijn, H. Edwin

2009-01-01

406

Evaluating Target Cold Spots By the use of Tail EUDs  

SciTech Connect

Purpose: To propose a new measure of target underdose that can be used in the evaluation and optimization of radiotherapy dose distributions. Methods and Materials: We compare various formulations of the equivalent uniform dose (EUD) and introduce a modification of existing EUD definitions, which we call tail EUD. Tail EUD is a measure of 'cold spots' below the prescription dose in the target dose distribution, using units of gray (Gy). We investigate the mathematical properties of various target EUD concepts, including tail EUD. We apply the tail EUD measure retrospectively to intensity modulated radiation therapy (IMRT) treatment plans from our plan database. We also use tail EUD as an optimization objective in the optimization of prostate, pancreas, and head-and-neck plans. Results: Tail EUD has desirable mathematical properties. In particular, it is convex and it leads to convex level sets (i.e., no local minima) if the EUD from which it is derived is concave. The tail EUD value is correlated with the subjective degree of target coverage. Constraining tail EUDs to a certain level in plan optimization leads to comparable target coverage in different plans and treatment sites. Conclusions: The newly introduced concept of tail EUD appears to be useful for both plan evaluation and optimization. In addition it can potentially be applied in the design of new clinical protocols.

Bortfeld, Thomas [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States)], E-mail: tbortfeld@partners.org; Craft, David [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Dempsey, James F. [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Halabi, Tarek [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Romeijn, H. Edwin [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Department of Industrial and Systems Engineering, University of Florida, Gainesville, FL (United States)

2008-07-01

407

A Chimeric Kinesin-1 Head/Kinesin-5 Tail Motor Switches between Diffusive and Processive Motility  

PubMed Central

Homotetrameric kinesin-5 motors are essential for chromosome separation and assembly of the mitotic spindle. These kinesins bind between two microtubules (MTs) and slide them apart, toward the spindle poles. This process must be tightly regulated in mitosis. In in vitro assays, Eg5 moves diffusively on single MTs and switches to a directed mode between MTs. How allosteric communication between opposing motor domains works remains unclear, but kinesin-5 tail domains may be involved. Here we present a single-molecule fluorescence study of a tetrameric kinesin-1 head/kinesin-5 tail chimera, DK4mer. This motor exhibited fast processive motility on single MTs interrupted by pauses. Like Eg5, DK4mer diffused along MTs with ADP, and slid antiparallel MTs apart with ATP. In contrast to Eg5, diffusive and processive periods were clearly distinguishable. This allowed us to measure transition rates among states and for unbinding as a function of buffer ionic strength. These data, together with results from controls using tail-less dimers, indicate that there are two modes of interaction with MTs, separated by an energy barrier. This result suggests a scheme of motor regulation that involves switching between two bound states, possibly allosterically controlled by the opposing tetramer end. Such a scheme is likely to be relevant for the regulation of native kinesin-5 motors. PMID:23442865

Thiede, Christina; Lakämper, Stefan; Wessel, Alok D.; Kramer, Stefanie; Schmidt, Christoph F.

2013-01-01

408

INTERPRETATION OF (596) SCHEILA'S TRIPLE DUST TAILS  

SciTech Connect

Strange-looking dust cloud around asteroid (596) Scheila was discovered on 2010 December 11.44-11.47. Unlike normal cometary tails, it consisted of three tails and faded within two months. We constructed a model to reproduce the morphology of the dust cloud based on the laboratory measurement of high-velocity impacts and the dust dynamics. As a result, we succeeded in reproducing the peculiar dust cloud by an impact-driven ejecta plume consisting of an impact cone and downrange plume. Assuming an impact angle of 45 Degree-Sign , our model suggests that a decameter-sized asteroid collided with (596) Scheila from the direction of ({alpha}{sub im}, {delta}{sub im}) = (60 Degree-Sign , -40 Degree-Sign ) in J2000 coordinates on 2010 December 3. The maximum ejection velocity of the dust particles exceeded 100 m s{sup -1}. Our results suggest that the surface of (596) Scheila consists of materials with low tensile strength.

Ishiguro, Masateru [Department of Physics and Astronomy, Seoul National University, Gwanak, Seoul 151-742 (Korea, Republic of); Hanayama, Hidekazu; Watanabe, Jun-ichi; Miyaji, Takeshi; Fukushima, Hideo [Ishigakijima Astronomical Observatory, National Astronomical Observatory of Japan, Ishigaki, Okinawa 907-0024 (Japan); Hasegawa, Sunao; Sarugaku, Yuki [Institute of Space and Astronautical Science (ISAS), JAXA, Sagamihara, Kanagawa 252-5210 (Japan); Fujiwara, Hideaki; Terada, Hiroshi [Subaru Telescope, National Astronomical Observatory of Japan, Hilo, HI 96720 (United States); Hsieh, Henry H. [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States); Vaubaillon, Jeremie J. [Observatoire de Paris, I.M.C.C.E., Denfert Rochereau, Bat. A., FR-75014 Paris (France); Kawai, Nobuyuki [Department of Physics, Tokyo Institute of Technology, Meguro, Tokyo 152-8551 (Japan); Yanagisawa, Kenshi; Kuroda, Daisuke [Okayama Astrophysical Observatory, National Astronomical Observatory of Japan, Asaguchi, Okayama 719-0232 (Japan); Ohta, Kouji [Department of Astronomy, Kyoto University, Sakyo, Kyoto 606-8502 (Japan); Hamanowa, Hiromi [Hamanowa Astronomical Observatory, Motomiya, Fukushima 969-1204 (Japan); Kim, Junhan [Yangcheon-gu, Seoul (Korea, Republic of); Pyo, Jeonghyun [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Nakamura, Akiko M., E-mail: ishiguro@snu.ac.kr [Department of Earth and Planetary Sciences, Kobe University, Nada, Kobe 657-8501 (Japan)

2011-11-15

409

The Pressure Distribution over the Horizontal Tail Surfaces of an Airplane III  

NASA Technical Reports Server (NTRS)

This report contains the results of an investigation of the distribution of pressure over the tail surfaces of a full-sized airplane during accelerated flight for the purpose of determining the magnitude of the tail and fuselage stresses in maneuvering. As the pressures in accelerated flight change in value with great rapidity, it was found that the liquid manometer used in the first part of this investigation would not be at all suitable under these conditions; so it was necessary to design and construct a new manometer containing a large number of recording diaphragm gauges for these measurements. Sixty openings on the tail surfaces were connected to this manometer and continuous records of pressures for each pair of holes were taken during various maneuvers. There were also recorded, simultaneously with the pressures, the normal acceleration at the center of gravity and the angular position of all the controls. The present investigation consisted in measuring on a standard rigged JN4H airplane the distribution of pressure over the whole of the horizontal tail surfaces while the airplane was being put through maneuvers as violently as it was thought safe, including spinning and pulling out of dives.

Norton, F H; Brown, W G

1923-01-01

410

Factors affecting the stimulus artifact tail in surface-recorded somatosensory-evoked potentials.  

PubMed

Surface-recorded somatosensory-evoked potentials (SEPs) are neural signals elicited by an external stimulus. In the case of electrically induced SEPs, the artifact generated by the stimulation process can severely distort the signal. In some cases, the artifact tail often lasts well into the initiation of the SEP making the determination of absolute latency very difficult. In this work, a new approach was taken to identify factors that affect the tail of the artifact. The methodology adopted was the development of a lumped electrical circuit model of the artifact generation process. While the modeling of the instrumentation hardware is relatively simple, this is not the case with tissue and electrode/skin interface effects. Consequently, this paper describes a novel tissue modeling approach that uses an autoregressive moving average (ARMA) parametric technique and an artificial neural network (ANN) to estimate tissue parameters from experimental data. This coupled with an estimation of the stimulation electrode-skin impedance completes the lumped circuit model. Simulink (The Mathworks Inc.) was used to evaluate the model under several different conditions. These results show that both the stimulation electrode-skin interface impedance and nature of the body tissue directly under the recording electrodes have a profound effect on the appearance of the stimulus artifact tail. This was verified by experimentally recorded data obtained from the median nerve using surface electrodes. Conclusions drawn from this work include that stimulation electrodes with low series capacitance should be used whenever possible to minimize the duration of the artifact tail. PMID:16937164

Hua, Y; Lovely, D F; Doraiswami, R

2006-03-01

411

Engineering assessment of inactive uranium mill tailings, Spook site, Converse County, Wyoming  

SciTech Connect

Ford, Bacon and Davis Utah Inc. has reevaluated the Spook site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings 48 mi northeast of Casper, in Converse County, Wyoming. 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 187,000 tons of tailings at the Spook 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 makes and gamma densitometers for measuring cross-sectionally averaged mass velocity in steady steam-water flow are presented. The results are interpreted ntation.

Not Available

1981-10-01

412

Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado  

SciTech Connect

This Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells. This risk assessment evaluates the most contaminated monitor wells at the processing site. It will be used to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium.

Not Available

1993-12-01

413

Muscle differentiation and morphogenesis in the regenerating tail of lizards.  

PubMed Central

The differentiation of muscles in the lizards Anolis and Lampropholis with tails that had regenerated for 21-50 d was investigated by light and electron microscope autoradiography using tritiated thymidine. At the apex of the regenerating tail, groups of 4-8 myoblasts of the promuscle aggregates fused to produce bundles of myotubes whose multiple labelled and unlabelled nuclei appeared to be distributed at random. The formation of the first myotubes and their growth is responsible for the formation of the myotome primordia and their separation from the intermuscular connective myosepta. More nuclei were added with the lengthening of the myotubes--up to 14-18 nuclei in the oldest proximal myotubes. At 4-5 h after injection labelled nuclei were found outside the myotubes while at 2-6 d after injection many labelled nuclei were observed in the myotubes, particularly near the two ends of the myotubular sarcoplasm contacting the myoseptum. This change from the initial distribution suggests that the growth of the myotubes takes place mostly at their terminals. There is an apparent correlation between the number of nuclei and the final length of the myotubes and myotome. The insertion of fibres with a similar number of nuclei and lengths into the pinnated connective myoseptum of the original musculature, the autotomy plane, probably determines the wave-like shape of the muscles within the regenerated myotomes. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Figs. 16-18 Fig. 19 Fig. 20 PMID:7649809

Alibardi, L

1995-01-01

414

The generation of proper constitutive G-tails on yeast telomeres is dependent on the MRX complex  

PubMed Central

The precise DNA arrangement at chromosomal ends and the proteins involved in its maintenance are of crucial importance for genome stability. For the yeast Saccharomyces cerevisiae, this constitutive DNA configuration has remained unknown. We demonstrate here that G-tails of 12–14 bases are present outside of S phase on normal yeast telomeres. Furthermore, the Mre11p protein is essential for the proper establishment of this constitutive end-structure. However, the timing of extended G-tails occurring during S phase is not affected in strains lacking Mre11p. Thus, G-tails are present on yeast chromosomes throughout the cell cycle and the MRX complex is required for their normal establishment. PMID:15198981

Larrivée, Michel; LeBel, Catherine; Wellinger, Raymund J.

2004-01-01

415

Radiologic characterization of the Mexican Hat, Utah, uranium mill tailings remedial action site: Addendum D1  

SciTech Connect

This radiologic characterization of the inactive uranium millsite at Mexican Hat, Utah, was conducted by Bendix Field Engineering Corporation for the US Department of Energy (DOE), Grand Junctions Project Office in response to and in accord with a Statement of Work prepared by the DOE Uranium Mill Tailings Remedial Action Project (UMTRAP) Technical Assistance Contractor, Jacobs Engineering Group, Inc. The objective of this project was to determine the horizontal and vertical extent of contamination that exceeds the US Environmental Protection Agency (EPA) standards at the Mexican Hat site. The data presented in this report are required for characterization of the areas adjacent to the Mexican Hat tailings piles and for the subsequent design of cleanup activities. Some on- pile sampling was required to determine the depth of the 15-pCi/g Ra- 226 interface in an area where wind and water erosion has taken place.

Ludlam, J.R.

1985-01-01

416

THE NARROW X-RAY TAIL AND DOUBLE H? TAILS OF ESO 137-002 IN A3627  

SciTech Connect

We present the analysis of a deep Chandra observation of a ?2 L{sub *} late-type galaxy, ESO 137-002, in the closest rich cluster A3627. The Chandra data reveal a long (?>40 kpc) and narrow tail with a nearly constant width (?3 kpc) to the southeast of the galaxy, and a leading edge ?1.5 kpc from the galaxy center on the upstream side of the tail. The tail is most likely caused by the nearly edge-on stripping of ESO 137-002's interstellar medium (ISM) by ram pressure, compared to the nearly face-on stripping of ESO 137-001 discussed in our previous work. Spectral analysis of individual regions along the tail shows that the gas throughout it has a rather constant temperature, ?1 keV, very close to the temperature of the tails of ESO 137-001, if the same atomic database is used. The derived gas abundance is low (?0.2 solar with the single-kT model), an indication of the multiphase nature of the gas in the tail. The mass of the X-ray tail is only a small fraction (<5%) of the initial ISM mass of the galaxy, suggesting that the stripping is most likely at an early stage. However, with any of the single-kT, double-kT, and multi-kT models we tried, the tail is always 'over-pressured' relative to the surrounding intracluster medium (ICM), which could be due to the uncertainties in the abundance, thermal versus non-thermal X-ray emission, or magnetic support in the ICM. The H? data from the Southern Observatory for Astrophysical Research show a ?21 kpc tail spatially coincident with the X-ray tail, as well as a secondary tail (?12 kpc long) to the east of the main tail diverging at an angle of ?23° and starting at a distance of ?7.5 kpc from the nucleus. At the position of the secondary H? tail, the X-ray emission is also enhanced at the ?2? level. We compare the tails of ESO 137-001 and ESO 137-002, and also compare the tails to simulations. Both the similarities and differences of the tails pose challenges to the simulations. Several implications are briefly discussed.

Zhang, B.; Lin, X. B.; Kong, X. [Center for Astrophysics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Sun, M. [Department of Physics, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Ji, L. [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, Jiangsu 210008 (China); Sarazin, C. [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States); Nulsen, P. E. J.; Forman, W.; Jones, C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Roediger, E. [Germany Hamburger Sternwarte, Universität Hamburg, Gojensbergsweg 112, D-21029 Hamburg (Germany); Donahue, M.; Voit, G. M., E-mail: xkong@ustc.edu.cn, E-mail: mingsun.cluster@gmail.com [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)

2013-11-10

417

Coevolution of caudal skeleton and tail feathers in birds.  

PubMed

Birds are capable of a wide range of aerial locomotor behaviors in part because of the derived structure and function of the avian tail. The tail apparatus consists of a several mobile (free) caudal vertebrae, a terminal skeletal element (the pygostyle), and an articulated fan of tail feathers that may be spread or folded, as well as muscular and fibroadipose structures that facilitate tail movements. Morphological variation in both the tail fan and the caudal skeleton that supports it are well documented. The structure of the tail feathers and the pygostyle each evolve in response to functional demands of differing locomotor behaviors. Here, I test whether the integument and skeleton coevolve in this important locomotor module. I quantified feather and skeletal morphology in a diverse sample of waterbirds and shorebirds using a combination of linear and geometric morphometrics. Covariation between tail fan shape and skeletal morphology was then tested using phylogenetic comparative methods. Pygostyle shape is found to be a good predictor of tail fan shape (e.g., forked, graduated), supporting the hypothesis that the tail fan and the tail skeleton have coevolved. This statistical relationship is used to reconstruct feather morphology in an exemplar fossil waterbird, Limnofregata azygosternon. Based on pygostyle morphology, this taxon is likely to have exhibited a forked tail fan similar to that of its extant sister clade Fregata, despite differing in inferred ecology and other aspects of skeletal anatomy. These methods may be useful in reconstructing rectricial morphology in other extinct birds and thus assist in characterizing the evolution of flight control surfaces in birds. PMID:25139752

Felice, Ryan N

2014-12-01

418

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

NASA Astrophysics Data System (ADS)

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 ra