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Sample records for hsp72 depletion suppresses

  1. Expression of HSP72 in the gastric mucosa is regulated by gastric acid in rats-Correlation of HSP72 expression with mucosal protection

    SciTech Connect

    Wada, Isao; Otaka, Michiro . E-mail: otaka@med.akita-u.ac.jp; Jin, Mario; Odashima, Masaru; Komatsu, Koga; Konishi, Noriaki; Matsuhashi, Tamotsu; Horikawa, Youhei; Ohba, Reina; Itoh, Hideaki; Watanabe, Sumio

    2006-10-20

    Background and aim: The real mechanism of adaptive cytoprotection in the gastric mucosa is not well established. In the present study, we investigated the effect of acid suppressing agents on a 72-kDa heat shock protein (HSP72) expression, which is known as endogenous cytoprotective factor, in the gastric mucosa. Also, the association of gastric mucosal protective function against HCl-challenge was compared between HSP72-induced and -reduced group. Materials and methods: Expression of HSP72 was measured by Western blotting in the gastric mucosa before and after administration of famotidine or omeprazole. The gastric mucosal protective function against 0.6 N HCl was compared between control group and HSP72-reduced group. Also, the effect of increased expression of gastric HSP72 by additional administration of zinc sulfate or zinc L-carnosine, which is known as HSP72-inducer, on mucosal protective function was studied. Results: HSP72 expression in the gastric mucosa was reduced by acid suppressing agents. The lowest expression level of HSP72 was observed 12 h (famotidine, H2-receptor antagonist) or 48 h (omeprazole, proton pump inhibitor) after administration. The gastric mucosal protective ability against 0.6 N HCl was also reduced when HSP72 expression was decreased by famotidine or omeprazole. This phenomenon was reversed by HSP72 induction by additional administration of zinc derivatives. Conclusion: Our results might indicate that the expression of HSP72 in the gastric mucosa is physiologically regulated by gastric acid, and that HSP72 induction could be important in view of mucosal protection especially when HSP72 expression is reduced by administration of acid suppressing agents such as proton pump inhibitor or H2 receptor antagonist.

  2. Adaptogens Stimulate Neuropeptide Y and Hsp72 Expression and Release in Neuroglia Cells

    PubMed Central

    Panossian, Alexander; Wikman, Georg; Kaur, Punit; Asea, Alexzander

    2011-01-01

    The beneficial stress–protective effect of adaptogens is related to the regulation of homeostasis via mechanisms of action associated with the hypothalamic–pituitary–adrenal axis and the regulation of key mediators of the stress response, such as molecular chaperones, stress-activated c-Jun N-terminal protein kinase, forkhead box O transcription factor, cortisol, and nitric oxide (NO). However, it still remains unclear what the primary upstream targets are in response to stimulation by adaptogens. The present study addresses this gap in our knowledge and suggests that an important target for adaptogen mediated stress–protective effector functions is the stress hormone neuropeptide Y (NPY). We demonstrated that ADAPT-232, a fixed combination of adaptogens Eleutherococcus senticosus root extract, Schisandra chinensis berry extract, Rhodiola rosea root extract SHR-5, and its active constituent salidroside, stimulated the expression of NPY and 72 kDa heat shock protein (Hsp72) in isolated human neuroglia cells. The central role of NPY was validated in experiments in which pre-treatment of human neuroglia cells with NPY-siRNA and HSF1-siRNA resulted in the significant suppression of ADAPT-232-induced NPY and Hsp72 release. Taken together our studies suggest that the stimulation and release of the stress hormones, NPY and Hsp72, into systemic circulation is an innate defense response against mild stressors (ADAPT-232), which increase tolerance and adaptation to stress. PMID:22347152

  3. Accumulation of stress protein 72 (HSP72) in muscle and spleen of goldfish taken into space

    NASA Astrophysics Data System (ADS)

    Ohnishi, T.; Tsuji, K.; Ohmura, T.; Matsumoto, H.; Wang, X.; Takahahsi, A.; Nagaoka, S.; Takabayashi, A.

    Using Western blot analysis, here, we report the levels of HSP72 in several organs from goldfish which were taken into space on the NASA space shuttle. A remarkable accumulation of HSP72 was detected in muscle and spleen of those fish taken into space as compared with controls. These results suggested that the HSP72 induction is a kind of stress response at the molecular level introduced by the space environment consisting of microgravity and/or cosmic radiation as stressors.

  4. Glutamine May Repress the Weak LPS and Enhance the Strong Heat Shock Induction of Monocyte and Lymphocyte HSP72 Proteins but May Not Modulate the HSP72 mRNA in Patients with Sepsis or Trauma

    PubMed Central

    Briassouli, Efrossini; Tzanoudaki, Marianna; Goukos, Dimitris; Routsi, Christina; Nanas, Serafim; Vardas, Kostas; Apostolou, Kleovoulos; Kanariou, Maria; Daikos, George; Briassoulis, George

    2015-01-01

    Objective. We assessed the lipopolysaccharide (LPS) or heat shock (HS) induction of heat shock protein-72 (HSP72) in peripheral blood mononuclear cells (PBMCs) of patients with severe sepsis (SS) or trauma-related systemic inflammatory response syndrome (SIRS), compared to healthy individuals (H); we also investigated any pre- or posttreatment modulating glutamine (Gln) effect. Methods. SS (11), SIRS (10), and H (19) PBMCs were incubated with 1 μg/mL LPS or 43°HS. Gln 10 mM was either added 1 h before or 1 h after induction or was not added at all. We measured monocyte (m), lymphocyte (l), mRNA HSP72, HSP72 polymorphisms, interleukins (ILs), monocyte chemoattractant protein-1 (MCP-1), and cortisol levels. Results. Baseline lHSP72 was higher in SS (p < 0.03), and mHSP72 in SIRS (p < 0.02), compared to H. Only HS induced l/mHSP72/mRNA HSP72; LPS induced IL-6, IL-8, IL-10, and MCP-1. Induced mRNA was related to l/mHSP72, and was related negatively to cytokines. Intracellular l/mHSP72/HSP72 mRNA was related to serum ILs, not being influenced by cortisol, illness severity, and HSP72 polymorphisms. Gln did not induce mRNA in any group but modified l/mHSP72 after LPS/HS induction unpredictably. Conclusions. HSP72 mRNA and l/mHSP72 are higher among critically ill patients, further induced by HS, not by LPS. HSP72 proteins and HSP72 mRNA are related to serum ILs and are negatively related to supernatant cytokines, not being influenced by HSP72 polymorphisms, cortisol, or illness severity. Gln may depress l/mHSP72 after LPS exposure and enhance them after HS induction, but it may not affect early induced HSP72 mRNA. PMID:26550577

  5. Hsp72 chaperone function is dispensable for protection against stress-induced apoptosis.

    PubMed

    Chow, Ari M; Steel, Rohan; Anderson, Robin L

    2009-05-01

    In addition to its role as a molecular chaperone, heat shock protein 72 (Hsp72) protects cells against a wide range of apoptosis inducing stresses. However, it is unclear if these two roles are functionally related or whether Hsp72 inhibits apoptosis by a mechanism independent of chaperone activity. The N-terminal adenosine triphosphatase domain, substrate-binding domain and the C-terminal EEVD regulatory motif of Hsp72 are all essential for chaperone activity. In this study, we show that Hsp72 mutants with a functional substrate-binding domain but lacking chaperone activity retain their ability to protect cells against apoptosis induced by heat and tumor necrosis factor alpha. In contrast, a deletion mutant lacking a functional substrate-binding domain has no protective capacity. The ability of the Hsp72 substrate-binding domain to inhibit apoptosis independent of the regulatory effects of the adenosine triphosphate-binding domain indicates that the inhibition of apoptosis may involve a stable binding interaction with a regulatory substrate rather than Hsp72 chaperone activity. PMID:18819021

  6. No endogenous circadian rhythm in resting plasma Hsp72 concentration in humans

    PubMed Central

    Fortes, Matthew B.

    2008-01-01

    Extra-cellular (e) heat shock protein (Hsp)72 has been shown to be elevated in a number of clinical conditions and has been proposed as a potential diagnostic marker. From a methodological and diagnostic perspective, it is important to investigate if concentrations of eHsp72 fluctuate throughout the day; hence, the purpose of the study was to measure resting concentrations of plasma eHsp72 throughout a 24-h period. Blood samples were taken every hour from 1200–2100 hours and from 0700–1200 hours the following day from seven healthy recreationally active males. Participants remained in the laboratory throughout the trial, performed light sedentary activities and were provided with standardised meals and fluids. Physical activity was quantified throughout by the use of an accelerometer. Ethylenediaminetetraacetic acid blood samples were analysed for eHsp72 concentration using a commercially available high-sensitivity enzyme-linked immunosorbent assay (intra-assay coefficient of variation = 1.4%). One-way repeated measures analysis of variance revealed that measures of physiological stress such as heart rate, systolic and diastolic blood pressure remained stable throughout the trial and subjects remained sedentary throughout (mean activity energy expenditure above resting metabolic rate—35.7 ± 10.0 kcal∙h−1). Plasma Hsp72 concentration did not fluctuate significantly throughout the day and showed no apparent endogenous circadian rhythm in absolute (P = 0.367) or plasma volume change corrected data (P = 0.380). Individual coefficients of variation ranged from 3.8–7.7% (mean 5.4%). Mean Hsp72 concentration across all subjects and time points was 1.49 ± 0.08 ng∙ml−1. These data show that in a rested state, plasma eHsp72 concentration shows no apparent endogenous circadian rhythm. PMID:18839337

  7. Activating HSP72 in rodent skeletal muscle increases mitochondrial number and oxidative capacity and decreases insulin resistance.

    PubMed

    Henstridge, Darren C; Bruce, Clinton R; Drew, Brian G; Tory, Kálmán; Kolonics, Attila; Estevez, Emma; Chung, Jason; Watson, Nadine; Gardner, Timothy; Lee-Young, Robert S; Connor, Timothy; Watt, Matthew J; Carpenter, Kevin; Hargreaves, Mark; McGee, Sean L; Hevener, Andrea L; Febbraio, Mark A

    2014-06-01

    Induction of heat shock protein (HSP)72 protects against obesity-induced insulin resistance, but the underlying mechanisms are unknown. Here, we show that HSP72 plays a pivotal role in increasing skeletal muscle mitochondrial number and oxidative metabolism. Mice overexpressing HSP72 in skeletal muscle (HSP72Tg) and control wild-type (WT) mice were fed either a chow or high-fat diet (HFD). Despite a similar energy intake when HSP72Tg mice were compared with WT mice, the HFD increased body weight, intramuscular lipid accumulation (triacylglycerol and diacylglycerol but not ceramide), and severe glucose intolerance in WT mice alone. Whole-body VO2, fatty acid oxidation, and endurance running capacity were markedly increased in HSP72Tg mice. Moreover, HSP72Tg mice exhibited an increase in mitochondrial number. In addition, the HSP72 coinducer BGP-15, currently in human clinical trials for type 2 diabetes, also increased mitochondrial number and insulin sensitivity in a rat model of type 2 diabetes. Together, these data identify a novel role for activation of HSP72 in skeletal muscle. Thus, the increased oxidative metabolism associated with activation of HSP72 has potential clinical implications not only for type 2 diabetes but also for other disorders where mitochondrial function is compromised. PMID:24430435

  8. Heat and exercise acclimation increases intracellular levels of Hsp72 and inhibits exercise-induced increase in intracellular and plasma Hsp72 in humans

    PubMed Central

    Magalhães, Flávio de Castro; Amorim, Fabiano Trigueiro; Passos, Renata L. Freitas; Fonseca, Michele Atalla; Oliveira, Kenya Paula Moreira; Lima, Milene Rodrigues Malheiros; Guimarães, Juliana Bohen; Ferreira-Júnior, João Batista; Martini, Angelo R. P.; Lima, Nilo R. V.; Soares, Danusa Dias; Oliveira, Edilamar Menezes

    2010-01-01

    In order to verify the effects of heat and exercise acclimation (HA) on resting and exercise-induced expression of plasma and leukocyte heat shock protein 72 (Hsp72) in humans, nine healthy young male volunteers (25.0 ± 0.7 years; 80.5 ± 2.0 kg; 180 ± 2 cm, mean ± SE) exercised for 60 min in a hot, dry environment (40 ± 0°C and 45 ± 0% relative humidity) for 11 days. The protocol consisted of running on a treadmill using a controlled hyperthermia technique in which the work rate was adjusted to elevate the rectal temperature by 1°C in 30 min and maintain it elevated for another 30 min. Before and after the HA, the volunteers performed a heat stress test (HST) at 50% of their individual maximal power output for 90 min in the same environment. Blood was drawn before (REST), immediately after (POST) and 1 h after (1 h POST) HST, and plasma and leukocytes were separated and stored. Subjects showed expected adaptations to HA: reduced exercise rectal and mean skin temperatures and heart rate, and augmented sweat rate and exercise tolerance. In HST1, plasma Hsp72 increased from REST to POST and then returned to resting values 1 h POST (REST: 1.11 ± 0.07, POST: 1.48 ± 0.10, 1 h POST: 1.22 ± 0.11 ng mL−1; p < 0.05). In HST2, there was no change in plasma Hsp72 (REST: 0.94 ± 0.08, POST: 1.20 ± 0.15, 1 h POST: 1.17 ± 0.16 ng mL−1; p > 0.05). HA increased resting levels of intracellular Hsp72 (HST1: 1 ± 0.02 and HST2: 4.2 ± 1.2 density units, p < 0.05). Exercise-induced increased intracellular Hsp72 expression was observed on HST1 (HST1: REST, 1 ± 0.02 vs. POST, 2.9 ± 0.9 density units, mean ± SE, p < 0.05) but was inhibited on HST2 (HST2: REST, 4.2 ± 1.2 vs. POST, 4.4 ± 1.1 density units, p > 0.05). Regression analysis showed that the lower the pre-exercise expression of intracellular Hsp72, the higher the exercise-induced increase (R = −0

  9. The Hsp72 response in peri-parturient dairy cows: relationships with metabolic and immunological parameters

    PubMed Central

    Catalani, Elisabetta; Amadori, Massimo; Vitali, Andrea; Bernabucci, Umberto; Nardone, Alessandro

    2010-01-01

    The study was aimed at assessing whether the peri-parturient period is associated with changes of intracellular and plasma inducible heat shock proteins (Hsp) 72 kDa molecular weight in dairy cows, and to establish possible relationships between Hsp72, metabolic, and immunological parameters subjected to changes around calving. The study was carried out on 35 healthy peri-parturient Holstein cows. Three, two, and one week before the expected calving, and 1, 2, 3, 4, and 5 weeks after calving, body conditions score (BCS) was measured and blood samples were collected to separate plasma and peripheral blood mononuclear cells (PBMC). Concentrations of Hsp72 in PBMC and plasma increased sharply after calving. In the post-calving period, BCS and plasma glucose declined, whereas plasma nonesterified fatty acids (NEFA) and tumor necrosis factor-alpha increased. The proliferative responses of PBMC to lipopolysaccharide (LPS) declined progressively after calving. The percentage of PBMC expressing CD14 receptors and Toll-like receptors (TLR)-4 increased and decreased in the early postpartum period, respectively. Correlation analysis revealed significant positive relationships between Hsp72 and NEFA, and between PBMC proliferation in response to LPS and the percentage of PBMC expressing TLR-4. Conversely, significant negative relationships were found between LPS-triggered proliferation of PBMC and both intracellular and plasma Hsp72. Literature data and changes of metabolic and immunological parameters reported herein authorize a few interpretative hypotheses and encourage further studies aimed at assessing possible cause and effect relationships between changes of PBMC and circulating Hsp72, metabolic, and immune parameters in dairy cows. PMID:20349286

  10. Effects of RRR-alpha-tocopherol on leukocyte expression of HSP72 in response to exhaustive treadmill exercise.

    PubMed

    Niess, A M; Fehrenbach, E; Schlotz, E; Sommer, M; Angres, C; Tschositsch, K; Battenfeld, N; Golly, I C; Biesalski, H K; Northoff, H; Dickhuth, H H

    2002-08-01

    Previous research revealed an increased expression of HSP72 in leukocytes after vigorous endurance exercise. We questioned whether more intensive but shorter exercise also induces leukocyte HSP72 synthesis. To delineate the role of reactive oxygen species (ROS) in exercise-related HSP72 induction, we additionally examined the effect of RRR-alpha-tocopherol (alpha-toc) on HSP72 expression using a double-blind placebo (P) controlled cross-over design. After supplementation with alpha-toc (500 I.U. daily) or P for 8 days, 9 male subjects performed a combined exhaustive treadmill protocol (total duration 29.4 +/- 2.0 min). HSP72 was assessed on mRNA (RT-PCR) and protein levels (flow cytometry). HSP72 mRNA rose 3 h after exercise only in the P group, but individual differences (alpha-toc - P) did not reveal significant treatment effects. A moderate but significant rise of HSP72 protein occurred in granulocytes up to 48 h after exercise. Three hours post-exercise, granulocyte HSP72 protein was lower when subjects received alpha-toc, but this effect vanished 24 and 48 h post-exercise. Exhaustive treadmill exercise augments HSP72 mRNA in leukocytes and induced a moderate but prolonged response of granulocyte HSP72 protein. These exercise effects are lower when compared to earlier findings obtained after vigorous endurance exercise. ROS seem to be involved, but do not play the major role in the induction of granulocyte HSP72 synthesis after exhaustive exercise. PMID:12215965

  11. Upregulation of Hsp72 mediates anoxia/reoxygention neuroprotection in the freshwater turtle via modulation of ROS

    PubMed Central

    Kesaraju, Shailaja; Nayak, Gauri; Prentice, Howard M.; Milton, Sarah L.

    2014-01-01

    The neuroprotective role of Hsp72 has been demonstrated in several ischemic/stroke models to occur primarily through mediation of apoptotic pathways, and a number of heat shock proteins are upregulated in animal models capable of extended anoxic survival. In the present study, we investigated the role of Hsp72 on cell death and apoptotic regulators in one anoxia tolerant model system, the freshwater turtle Trachemys scripta. Since Hsp72 is known to regulate apoptosis through interactions with Bcl-2, we manipulated the levels of Hsp72 and Bcl-2 with siRNA in neuronally enriched primary cell cultures and examined downstream effects. The knockdown of either Hsp72 or Bcl-2 induced cell death during anoxia and reoxygenation. Knockdown of Bcl-2 resulted in increases in apoptotic markers and increased ROS levels 2-fold. However, significant knockdown of Hsp72 did not have any effect on the expression of key mitochondrial apoptotic regulators such as Cytochrome c and caspase-3. Hsp72 knockdown however significantly increased Apoptosis Inducing Factor in both anoxia and reoxygenation and resulted in a six-fold induction of hydrogen peroxide levels. These findings suggest that the neuroprotection offered by Hsp72 in the anoxia/reoxygenation tolerant turtle is through the mediation of ROS levels and not through modulation of caspase-dependent pathways. PMID:25107858

  12. Cytosolic calcium transients are a determinant of contraction-induced HSP72 transcription in single skeletal muscle fibers.

    PubMed

    Stary, Creed M; Hogan, Michael C

    2016-05-15

    The intrinsic activating factors that induce transcription of heat shock protein 72 (HSP72) in skeletal muscle following exercise remain unclear. We hypothesized that the cytosolic Ca(2+) transient that occurs with depolarization is a determinant. We utilized intact, single skeletal muscle fibers from Xenopus laevis to test the role of the cytosolic Ca(2+) transient and several other exercise-related factors (fatigue, hypoxia, AMP kinase, and cross-bridge cycling) on the activation of HSP72 transcription. HSP72 and HSP60 mRNA levels were assessed with real-time quantitative PCR; cytosolic Ca(2+) concentration ([Ca(2+)]cyt) was assessed with fura-2. Both fatiguing and nonfatiguing contractions resulted in a significant increase in HSP72 mRNA. As expected, peak [Ca(2+)]cyt remained tightly coupled with peak developed tension in contracting fibers. Pretreatment with N-benzyl-p-toluene sulfonamide (BTS) resulted in depressed peak developed tension with stimulation, while peak [Ca(2+)]cyt remained largely unchanged from control values. Despite excitation-contraction uncoupling, BTS-treated fibers displayed a significant increase in HSP72 mRNA. Treatment of fibers with hypoxia (Po2: <3 mmHg) or AMP kinase activation had no effect on HSP72 mRNA levels. These results suggest that the intermittent cytosolic Ca(2+) transient that occurs with skeletal muscle depolarization provides a sufficient activating stimulus for HSP72 transcription. Metabolic or mechanical factors associated with fatigue development and cross-bridge cycling likely play a more limited role. PMID:26869714

  13. Effects of voluntary exercise and genetic selection for high activity levels on HSP72 expression in house mice.

    PubMed

    Belter, Jason G; Carey, Hannah V; Garland, Theodore

    2004-04-01

    We studied expression of heat shock protein 72 (HSP72) in female mice from four replicate lines that had been selectively bred for high voluntary wheel running (S) and from four random-bred control lines (C). Mice from generation 23 were sampled after 6 days of wheel access, and those from generation 14 were sampled after 8 wk of access to wheels either free to rotate or locked. Mice from S lines ran approximately 2.6 times as many revolutions per day as did those from C lines. Western blotting of tissues from generation 23 mice indicated that S mice had elevated HSP72 expression in triceps surae muscle, but levels in spleen, kidney, heart, and lung were similar in S and C mice. HSP72 expression in triceps surae from generation 14 mice was measured by ELISA and analyzed with a two-way analysis of covariance. The interaction between wheel type and line type (S vs. C) was statistically significant, and subsequent analyses indicated that S mice had significantly elevated HSP72 expression only when housed with free wheels. Mice with the previously described mini-muscle phenotype (Houle-Leroy P, Guderley H, Swallow JG, and Garland T Jr. Am J Physiol Regul Integr Comp Physiol 284: R433-R443, 2003) occurred in both generations and had elevated HSP72 expression in triceps surae. For the generation 23 sample, wheel running as a covariate had a significant negative association with HSP72 expression, and the effect of line type was still statistically significant. Therefore, the increased HSP72 expression of S mice is not a simple proximate effect of their increased wheel running. PMID:14672969

  14. Genetic manipulation of cardiac Hsp72 levels does not alter substrate metabolism but reveals insights into high-fat feeding-induced cardiac insulin resistance.

    PubMed

    Henstridge, Darren C; Estevez, E; Allen, T L; Heywood, S E; Gardner, T; Yang, C; Mellett, N A; Kingwell, B A; Meikle, P J; Febbraio, M A

    2015-05-01

    Heat shock protein 72 (Hsp72) protects cells against a variety of stressors, and multiple studies have suggested that Hsp72 plays a cardioprotective role. As skeletal muscle Hsp72 overexpression can protect against high-fat diet (HFD)-induced insulin resistance, alterations in substrate metabolism may be a mechanism by which Hsp72 is cardioprotective. We investigated the impact of transgenically overexpressing (Hsp72 Tg) or deleting Hsp72 (Hsp72 KO) on various aspects of cardiac metabolism. Mice were fed a normal chow (NC) or HFD for 12 weeks from 8 weeks of age to examine the impact of diet-induced obesity on metabolic parameters in the heart. The HFD resulted in an increase in cardiac fatty acid oxidation and a decrease in cardiac glucose oxidation and insulin-stimulated cardiac glucose clearance; however, there was no difference in Hsp72 Tg or Hsp72 KO mice in these rates compared with their respective wild-type control mice. Although HFD-induced cardiac insulin resistance was not rescued in the Hsp72 Tg mice, it was preserved in the skeletal muscle, suggesting tissue-specific effects of Hsp72 overexpression on substrate metabolism. Comparison of two different strains of mice (BALB/c vs. C57BL/6J) also identified strain-specific differences in regard to HFD-induced cardiac lipid accumulation and insulin resistance. These strain differences suggest that cardiac lipid accumulation can be dissociated from cardiac insulin resistance. Our study finds that genetic manipulation of Hsp72 does not lead to alterations in metabolic processes in cardiac tissue under resting conditions, but identifies mouse strain-specific differences in cardiac lipid accumulation and insulin-stimulated glucose clearance. PMID:25618331

  15. Isothermic and fixed-intensity heat acclimation methods elicit equal increases in Hsp72 mRNA.

    PubMed

    Gibson, O R; Mee, J A; Taylor, L; Tuttle, J A; Watt, P W; Maxwell, N S

    2015-06-01

    Thermotolerance, to which heat shock protein-72 (Hsp72) contributes, is an acquired state achieved following heat acclimation (HA), eliciting cellular adaption and protection against thermal stress. Optimal HA methods achieving the greatest heat shock response (HSR) are equivocal; therefore, investigation of methods provoking the greatest sustained HSR is required to optimize cellular adaptation. Twenty-four males performed short-term HA (STHA; five sessions) and long-term HA (LTHA; STHA plus further five sessions) utilizing fixed-intensity (FIXED; workload = 50% V ˙ O 2 p e a k ), continuous isothermic HA [ISOCONT ; target rectal temperature (Trec ) = 38.5 °C], or progressive isothermic HA (ISOPROG ; target Trec  = 38.5 °C for STHA then target Trec  = 39.0 °C for LTHA). Leukocyte Hsp72 mRNA was measured pre- and post day 1, day 5, and day 10 of HA via reverse transcription quantitative polymerase chain reaction to determine the HSR. Hsp72 mRNA increased (P < 0.05) pre- to post day 1, pre- to post day 5, and pre to post day 10 in FIXED, ISOCONT , and ISOPROG , but no differences were observed between methods (P > 0.05). The equal Hsp72 mRNA increases occurring from consistent, reduced, or increased endogenous strain following STHA and LTHA suggest that transcription occurs following attainment of sufficient endogenous criteria. These data give confidence that all reported HA methods increase Hsp72 mRNA and are capable of eliciting adaptations toward thermotolerance. PMID:25943677

  16. HSP72 as a complementary protection against oxidative stress induced by exercise in the soleus muscle of rats.

    PubMed

    Smolka, M B; Zoppi, C C; Alves, A A; Silveira, L R; Marangoni, S; Pereira-Da-Silva, L; Novello, J C; Macedo, D V

    2000-11-01

    Given the potential of reactive oxygen species to damage intracellular proteins during subsequent bouts of muscle contractions, it was suggested that, when this production exceeds the antioxidant capacity, the preexisting antioxidant pathways may be complemented by the synthesis of the defense mechanism represented by heat shock proteins (HSPs), stress proteins with the function of repair and maintaining protein folding. To test this hypothesis, we analyzed reactive carbonyl derivatives in plasma and the expression of HSP72 and activities of enzymes from the oxidative and antioxidant defense systems in the soleus muscle of sedentary rats and rats trained by two protocols: continuous and intermittent. We analyzed all three groups at rest and 2 h after acute exercise. After 8 wk of training, the animals from both groups clearly demonstrated higher resistance to exercise. Both trained groups showed significantly higher citrate synthase, catalase, and glutathione reductase activities than the control group (P < 0.01). After acute exercise, catalase and glutathione reductase activities significantly decreased (P < 0.01) and plasma reactive carbonyl derivatives significantly increased (P < 0.05) in the sedentary group, suggesting an oxidative-stress condition as responsible for exhaustion in this group. Finally, after acute exercise, the induction of HSP72 expression occurred only in the sedentary group, suggesting that HSP72 acts as a complementary protective mechanism in exercise-induced oxidative stress. PMID:11049834

  17. Evaluation of molecular chaperons Hsp72 and neuropeptide Y as characteristic markers of adaptogenic activity of plant extracts.

    PubMed

    Asea, Alexzander; Kaur, Punit; Panossian, Alexander; Wikman, Karl Georg

    2013-11-15

    We have previously demonstrated that ADAPT-232, a fixed combination of adaptogenic substances derived from Eleutherococcus senticosus root extract, Schisandra chinensis berry extract, Rhodiola rosea root extract stimulated the expression and release of neuropeptide Y (NPY) and molecular chaperone Hsp72 from isolated human neurolgia cells. Both of these mediators of stress response are known to play an important role in regulation of neuroendocrine system and immune response. We further demonstrated that ADAPT-232 induced release of Hsp70 is mediated by NPY, suggesting an existence of NPY-mediated pathway of activation of Hsp72 release into the blood circulation system. The objective of this study was to determine whether this pathway is common for adaptogens and whether NPY and/or Hsp72 can be considered as necessary specific biomarkers for adaptogenic activity. The release of NPY and Hsp72 from neuroglia cells in response to treatment with various plant extracts (n=23) including selected validated adaptogens, partly validated adaptogens, claimed but negligibly validated adaptogens and some other plant extracts affecting neuroendocrine and immune systems but never considered as adaptogens was measured using high throughput ELISA techniques. We demonstrated that adaptogens, e.g. R. rosea, S. chinensis and E. senticosus stimulate both NPY and Hsp70 release from neuroblastoma cells, while tonics and stimulants have no significant effect on NPY in this in vitro test. In the groups of partly validated adaptogens the effect of Panax ginseng and Withania somnifera was not statistically significant both on NPY and Hsp70 release, while the activating effect of Bryonia alba and Rhaponticum cartamoides was significant only on Hsp70. In contrast, all tested non-adaptogens, such as antiinflammatoty plant extracts Matricaria recutita, Pelargonium sidoides, Hedera helix and Vitis vinifera significantly inhibit Hsp70 release and have no influence on NPY release from neuroblastoma

  18. Hsp72 (HSPA1A) Prevents Human Islet Amyloid Polypeptide Aggregation and Toxicity: A New Approach for Type 2 Diabetes Treatment

    PubMed Central

    Rosas, Paola C.; Nagaraja, Ganachari M.; Kaur, Punit; Panossian, Alexander; Wickman, Georg; Garcia, L. Rene; Al-Khamis, Fahd A.; Asea, Alexzander A. A.

    2016-01-01

    Type 2 diabetes is a growing public health concern and accounts for approximately 90% of all the cases of diabetes. Besides insulin resistance, type 2 diabetes is characterized by a deficit in β-cell mass as a result of misfolded human islet amyloid polypeptide (h-IAPP) which forms toxic aggregates that destroy pancreatic β-cells. Heat shock proteins (HSP) play an important role in combating the unwanted self-association of unfolded proteins. We hypothesized that Hsp72 (HSPA1A) prevents h-IAPP aggregation and toxicity. In this study, we demonstrated that thermal stress significantly up-regulates the intracellular expression of Hsp72, and prevents h-IAPP toxicity against pancreatic β-cells. Moreover, Hsp72 (HSPA1A) overexpression in pancreatic β-cells ameliorates h-IAPP toxicity. To test the hypothesis that Hsp72 (HSPA1A) prevents aggregation and fibril formation, we established a novel C. elegans model that expresses the highly amyloidogenic human pro-IAPP (h-proIAPP) that is implicated in amyloid formation and β-cell toxicity. We demonstrated that h-proIAPP expression in body-wall muscles, pharynx and neurons adversely affects C. elegans development. In addition, we demonstrated that h-proIAPP forms insoluble aggregates and that the co-expression of h-Hsp72 in our h-proIAPP C. elegans model, increases h-proIAPP solubility. Furthermore, treatment of transgenic h-proIAPP C. elegans with ADAPT-232, known to induce the expression and release of Hsp72 (HSPA1A), significantly improved the growth retardation phenotype of transgenic worms. Taken together, this study identifies Hsp72 (HSPA1A) as a potential treatment to prevent β-cell mass decline in type 2 diabetic patients and establishes for the first time a novel in vivo model that can be used to select compounds that attenuate h-proIAPP aggregation and toxicity. PMID:26960140

  19. Downhill running and exercise in hot environments increase leukocyte Hsp72 (HSPA1A) and Hsp90α (HSPC1) gene transcripts.

    PubMed

    Tuttle, James A; Castle, Paul C; Metcalfe, Alan J; Midgley, Adrian W; Taylor, Lee; Lewis, Mark P

    2015-04-15

    Stressors within humans and other species activate Hsp72 and Hsp90α mRNA transcription, although it is unclear which environmental temperature or treadmill gradient induces the largest increase. To determine the optimal stressor for priming the Hsp system, physically active but not heat-acclimated participants (19.8 ± 1.9 and 20.9 ± 3.6 yr) exercised at lactate threshold in either temperate (20°C, 50% relative humidity; RH) or hot (30°C, 50% RH) environmental conditions. Within each condition, participants completed a flat running (temperate flat or hot flat) and a downhill running (temperate downhill or hot downhill) experimental trial in a randomized counterbalanced order separated by at least 7 days. Venous blood samples were taken immediately before (basal), immediately after exercise, and 3 and 24 h postexercise. RNA was extracted from leukocytes and RT-quantitative PCR conducted to determine Hsp72 and Hsp90α mRNA relative expression. Leukocyte Hsp72 mRNA was increased immediately after exercise following downhill running (1.9 ± 0.9-fold) compared with flat running (1.3 ± 0.4-fold; P = 0.001) and in hot (1.9 ± 0.6-fold) compared with temperate conditions (1.1 ± 0.5-fold; P = 0.003). Leukocyte Hsp90α mRNA increased immediately after exercise following downhill running (1.4 ± 0.8-fold) compared with flat running (0.9 ± 0.6-fold; P = 0.002) and in hot (1.6 ± 1.0-fold) compared with temperate conditions (0.9 ± 0.6-fold; P = 0.003). Downhill running and exercise in hot conditions induced the largest stimuli for leukocyte Hsp72 and Hsp90α mRNA increases. PMID:25722377

  20. Increasing self-regulatory strength can reduce the depleting effect of suppressing stereotypes.

    PubMed

    Gailliot, Matthew T; Plant, E Ashby; Butz, David A; Baumeister, Roy F

    2007-02-01

    Three longitudinal studies and one correlational study tested the hypothesis that increasing self-regulatory strength by regular self-regulatory exercise would reduce the intrapsychic costs of suppressing stereotypes. Participants tried to resist using stereotypes while describing or talking to a stimulus person. Participants whose habitual motivation to suppress stereotypes was low exhibited impaired Stroop and anagram performance after the suppression task, presumably because of self-regulatory depletion (i.e., a reduction of self-regulatory strength following prior use). Two weeks of self-regulation exercises (such as using one's nondominant hand or refraining from cursing) eliminated this effect. These findings indicate that self-regulatory exercise can improve resistance to self-regulatory depletion and, consequently, people can suppress stereotypes without suffering subsequent decrements in task performance. PMID:17259587

  1. Expressions of caspase-3, Tunel, and Hsp72 immunoreactivities in cultured spinal cord neurons of rat after exposure to glutamate, nitric oxide, or peroxynitrite.

    PubMed

    Manabe, Y; Wang, J; Warita, H; Shiro, Y; Abe, K

    2001-07-01

    Although excitotoxic and oxidative stress play important roles in spinal neuron death, the exact mechanisms are not fully understood. We examined cell damage of primary culture of 11 day-old rat spinal cord by addition of glutamate, nitric oxice (NO) or peroxynitrite (PN) with detection of caspase-3, terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick end labeling (TUNEL) or 72 kDa heat shock protein (HSP72). With addition of glutamate, NOC18 (a slow NO releaser) or PN, immunoreactivity for caspase-3 became stronger in the cytoplasm of large motor neurons in the ventral horn at 6 to 24 hr. TUNEL positive nuclei were found in spinal large motor neurons from 24 h and the positive cell proportion greatly increased at 48 h in contrast to the vehicle. On the other hand, the immunoreactivity of HSP72 in the ventral horn was already positive at 0 h, and gradually decreased in the course of time with glutamate, NOC18 or PN than vehicle treatment. In the dorsal horn, the proportion of caspase-3 positive small neurons greatly increased at 6 to 48 h after addition of glutamate. The present results suggest that both excitotoxic and oxidative stress play important roles in the apoptotic pathway in cultured spinal neurons. PMID:15111253

  2. Depletion of white adipocyte progenitors induces beige adipocyte differentiation and suppresses obesity development.

    PubMed

    Daquinag, A C; Tseng, C; Salameh, A; Zhang, Y; Amaya-Manzanares, F; Dadbin, A; Florez, F; Xu, Y; Tong, Q; Kolonin, M G

    2015-02-01

    Overgrowth of white adipose tissue (WAT) in obesity occurs as a result of adipocyte hypertrophy and hyperplasia. Expansion and renewal of adipocytes relies on proliferation and differentiation of white adipocyte progenitors (WAP); however, the requirement of WAP for obesity development has not been proven. Here, we investigate whether depletion of WAP can be used to prevent WAT expansion. We test this approach by using a hunter-killer peptide designed to induce apoptosis selectively in WAP. We show that targeted WAP cytoablation results in a long-term WAT growth suppression despite increased caloric intake in a mouse diet-induced obesity model. Our data indicate that WAP depletion results in a compensatory population of adipose tissue with beige adipocytes. Consistent with reported thermogenic capacity of beige adipose tissue, WAP-depleted mice display increased energy expenditure. We conclude that targeting of white adipocyte progenitors could be developed as a strategy to sustained modulation of WAT metabolic activity. PMID:25342467

  3. Depletion of white adipocyte progenitors induces beige adipocyte differentiation and suppresses obesity development

    PubMed Central

    Daquinag, A C; Tseng, C; Salameh, A; Zhang, Y; Amaya-Manzanares, F; Dadbin, A; Florez, F; Xu, Y; Tong, Q; Kolonin, M G

    2015-01-01

    Overgrowth of white adipose tissue (WAT) in obesity occurs as a result of adipocyte hypertrophy and hyperplasia. Expansion and renewal of adipocytes relies on proliferation and differentiation of white adipocyte progenitors (WAP); however, the requirement of WAP for obesity development has not been proven. Here, we investigate whether depletion of WAP can be used to prevent WAT expansion. We test this approach by using a hunter-killer peptide designed to induce apoptosis selectively in WAP. We show that targeted WAP cytoablation results in a long-term WAT growth suppression despite increased caloric intake in a mouse diet-induced obesity model. Our data indicate that WAP depletion results in a compensatory population of adipose tissue with beige adipocytes. Consistent with reported thermogenic capacity of beige adipose tissue, WAP-depleted mice display increased energy expenditure. We conclude that targeting of white adipocyte progenitors could be developed as a strategy to sustained modulation of WAT metabolic activity. PMID:25342467

  4. Silencing of Hsp27 and Hsp72 in glioma cells as a tool for programmed cell death induction upon temozolomide and quercetin treatment

    SciTech Connect

    Jakubowicz-Gil, Joanna; Langner, Ewa; Bądziul, Dorota; Wertel, Iwona; Rzeski, Wojciech

    2013-12-15

    The aim of the present study was to investigate whether silencing of Hsp27 or Hsp72 expression in glioblastoma multiforme T98G and anaplastic astrocytoma MOGGCCM cells increases their sensitivity to programmed cell death induction upon temozolomide and/or quercetin treatment. Transfection with specific siRNA was performed for the Hsp gene silencing. As revealed by microscopic observation and flow cytometry, the inhibition of Hsp expression was correlated with severe apoptosis induction upon the drug treatment studied. No signs of autophagy were detected. This was correlated with a decreased mitochondrial membrane potential, increased level of cytochrome c in the cytoplasm, and activation of caspase 3 and caspase 9. All these results suggest that the apoptotic signal was mediated by an internal pathway. Additionally, in a large percentage of cells treated with temozolomide, with or without quercetin, granules within the ER system were found, which was accompanied by an increased level of caspase 12 expression. This might be correlated with ER stress. Quercetin and temozolomide also changed the shape of nuclei from circular to “croissant like” in both transfected cell lines. Our results indicate that blocking of Hsp27 and Hsp72 expression makes T98G cells and MOGGCCM cells extremely vulnerable to apoptosis induction upon temozolomide and quercetin treatment and that programmed cell death is initiated by an internal signal. - Highlights: • Hsps gene silencing induced severe apoptosis upon temozolomide–quercetin treatment • Apoptosis in transfected glioma cells was initiated by internal signal • Programmed cell death was preceded by ER stress • Temozolomide–quercetin treatment changed nuclei shape in transfected glioma cells.

  5. Saikosaponin-D attenuates heat stress-induced oxidative damage in LLC-PK1 cells by increasing the expression of anti-oxidant enzymes and HSP72.

    PubMed

    Zhang, Bao-Zhen; Guo, Xiao-Tong; Chen, Jian-Wei; Zhao, Yuan; Cong, Xia; Jiang, Zhong-Ling; Cao, Rong-Feng; Cui, Kai; Gao, Shan-Song; Tian, Wen-Ru

    2014-01-01

    Heat stress stimulates the production of reactive oxygen species (ROS), which cause oxidative damage in the kidney. This study clarifies the mechanism by which saikosaponin-d (SSd), which is extracted from the roots of Bupleurum falcatum L, protects heat-stressed pig kidney proximal tubular (LLC-PK1) cells against oxidative damage. SSd alone is not cytotoxic at concentrations of 1 or 3 μg/mL as demonstrated by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. To assess the effects of SSd on heat stress-induced cellular damage, LLC-PK1 cells were pretreated with various concentrations of SSd, heat stressed at 42°C for 1 h, and then returned to 37°C for 9 h. DNA ladder and MTT assays demonstrated that SSd helped to prevent heat stress-induced cellular damage when compared to untreated cells. Additionally, pretreatment with SSd increased the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) but decreased the concentration of malondialdehyde (MDA) in a dose-dependent manner when compared to controls. Furthermore, real-time PCR and Western blot analysis demonstrated that SSd significantly increased the expression of copper and zinc superoxide dismutase (SOD-1), CAT, GPx-1 and heat shock protein 72 (HSP72) at both the mRNA and protein levels. In conclusion, these results are the first to demonstrate that SSd ameliorates heat stress-induced oxidative damage by modulating the activity of anti-oxidant enzymes and HSP72 in LLC-PK1 cells. PMID:25169909

  6. Post-exercise cold water immersion does not alter high intensity interval training-induced exercise performance and Hsp72 responses, but enhances mitochondrial markers.

    PubMed

    Aguiar, Paula Fernandes; Magalhães, Sílvia Mourão; Fonseca, Ivana Alice Teixeira; da Costa Santos, Vanessa Batista; de Matos, Mariana Aguiar; Peixoto, Marco Fabrício Dias; Nakamura, Fábio Yuzo; Crandall, Craig; Araújo, Hygor Nunes; Silveira, Leonardo Reis; Rocha-Vieira, Etel; de Castro Magalhães, Flávio; Amorim, Fabiano Trigueiro

    2016-09-01

    This study aims to evaluate the effect of regular post-exercise cold water immersion (CWI) on intramuscular markers of cellular stress response and signaling molecules related to mitochondria biogenesis and exercise performance after 4 weeks of high intensity interval training (HIIT). Seventeen healthy subjects were allocated into two groups: control (CON, n = 9) or CWI (n = 8). Each HIIT session consisted of 8-12 cycling exercise stimuli (90-110 % of peak power) for 60 s followed by 75 s of active recovery three times per week, for 4 weeks (12 HIIT sessions). After each HIIT session, the CWI had their lower limbs immersed in cold water (10 °C) for 15 min and the CON recovered at room temperature. Exercise performance was evaluated before and after HIIT by a 15-km cycling time trial. Vastus lateralis biopsies were obtained pre and 72 h post training. Samples were analyzed for heat shock protein 72 kDa (Hsp72), adenosine monophosphate-activated protein kinase (AMPK), and phosphorylated p38 mitogen-activated protein kinase (p-p38 MAPK) assessed by western blot. In addition, the mRNA expression of heat shock factor-1 (HSF-1), peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), nuclear respiratory factor 1 and 2 (NRF1 and 2), mitochondrial transcription factor A (Tfam), calcium calmodulin-dependent protein kinase 2 (CaMK2) and enzymes citrate synthase (CS), carnitine palmitoyltransferase I (CPT1), and pyruvate dehydrogenase kinase (PDK4) were assessed by real-time PCR. Time to complete the 15-km cycling time trial was reduced with training (p < 0.001), but was not different between groups (p = 0.33). The Hsp72 (p = 0.01), p38 MAPK, and AMPK (p = 0.04) contents increased with training, but were not different between groups (p > 0.05). No differences were observed with training or condition for mRNA expression of PGC-1α (p = 0.31), CPT1 (p = 0.14), CS (p = 0.44), and NRF-2 (p = 0.82). However

  7. Expression of heat shock protein (HSP 72 kD) during acute methamphetamine intoxication depends on brain hyperthermia: neurotoxicity or neuroprotection?

    PubMed Central

    Kiyatkin, Eugene A.; Sharma, Hari S.

    2011-01-01

    In the present study, light and electron microscopy were used to examine heat shock protein (HSP 72kD) expression during acute methamphetamine (METH) intoxication in rats and evaluate its relationships with brain temperature and alterations in a number of other histochemical and morphological parameters. Freely moving rats received METH at the same dose (9 mg/kg, sc) but at different ambient temperatures (23 and 29°C), showing a wide range of brain temperature elevations (37.6–42.5°C); brains were taken for histochemical and morphological evaluations at peak of brain temperature increase. We found that acute METH intoxication induces massive and wise-spread HSP expression in neural and glial cells examined in details in the cortex, hippocampus, thalamus, and hypothalamus. In each of these structures, the number of HSP-positive cells tightly correlated with brain temperature elevation. The changes in HSP immunoreactivity were also tightly related to alterations in permeability of the blood-brain barrier, acute glial activation and brain edema assessed by albumin and GFAP immunoreactivity and measuring tissue water content, respectively. While robust and generalized HSP production normally appears to be the part of an adaptive brain response associated with METH-induced metabolic activation, activation of this protective mechanism has its natural limits and could not counteract the damaging effects of oxidative stress, high temperature and edema – the leading factors of METH-induced neurotoxicity. PMID:20931246

  8. The impact of submaximal exercise during heat and/or hypoxia on the cardiovascular and monocyte HSP72 responses to subsequent (post 24 h) exercise in hypoxia

    PubMed Central

    2014-01-01

    Background The aims of this study were to describe the cellular stress response to prolonged endurance exercise in acute heat, hypoxia and the combination of heat and hypoxia and to determine whether prior acute exposure to these stressors improved cellular tolerance to a subsequent exercise bout in hypoxia 24 h later. Methods Twelve males (age 22 ± 4 years, height 1.77 ± 0.05 m, mass 79 ± 12.9 kg, VO2 max 3.57 ± 0.7 L · min-1) completed four trials (30-min rest, 90-min cycling at 50% normoxic VO2 max) in normothermic normoxia (NORM; 18°C, FIO2 = 0.21), heat (HEAT; 40°C, 20% RH), hypoxia (HYP; FIO2 = 0.14) or a combination of heat and hypoxia (COM; 40°C, 20% RH, FIO2 = 0.14) separated by at least 7 days. Twenty-four hours after each trial, participants completed a hypoxic stress test (HST; 15-min rest, 60-min cycling at 50% normoxic VO2 max, FIO2 = 0.14). Monocyte heat shock protein 72 (mHSP72) was assessed immediately before and after each exercise bout. Results mHSP72 increased post exercise in NORM (107% ± 5.5%, p > 0.05), HYP (126% ± 16%, p < 0.01), HEAT (153% ± 14%, p < 0.01) and COM (161% ± 32%, p < 0.01). mHSP72 had returned to near-resting values 24 h after NORM (97% ± 8.6%) but was elevated after HEAT (130% ± 19%), HYP (118% ± 17%) and COM (131% ± 19%) (p < 0.05). mHSP72 increased from baseline after HSTNORM (118% ± 12%, p < 0.05), but did not increase further in HSTHEAT, HSTHYP and HSTCOM. Conclusions The prior induction of mHSP72 as a result of COM, HEAT and HYP attenuated further mHSP72 induction after HST and was indicative of conferred cellular tolerance. PMID:25343025

  9. Naturally-occurring expressive suppression in daily life depletes executive functioning.

    PubMed

    Franchow, Emilie I; Suchy, Yana

    2015-02-01

    The depleting impact of experimentally manipulated expressive suppression (ES) on cognition (especially executive functioning and related processes) has been well established (Baumeister, 2002a). However, the impact of ES that occurs naturally in the course of daily life has not been examined. Sixty two adults (M = 22.89 years old) completed questions about recent ES burden (over the past 2 weeks and on the test day) and completed cognitive measures assessing executive functioning, working memory, and speed of information processing. Individuals with higher-than-usual burden of ES on the test day exhibited poorer executive performance and those with high ES over the past 2 weeks exhibited poorer processing speed above and beyond depression, suggesting that ES burden as it occurs in the course of daily life is associated with compromised cognitive performance. PMID:25111882

  10. Suppression of resonance Raman scattering via ground state depletion towards sub-diffraction-limited label-free microscopy.

    PubMed

    Rieger, Steffen; Fischedick, Markus; Boller, Klaus-Jochen; Fallnich, Carsten

    2016-09-01

    We report on the first experimental demonstration of the suppression of spontaneous Raman scattering via ground state depletion. The concept of Raman suppression can be used to achieve sub-diffraction-limited resolution in label-free microscopy by exploiting spatially selective signal suppression when imaging a sample with a combination of Gaussian- and donut-shaped beams and reconstructing a resolution-enhanced image from this data. Using a nanosecond pulsed laser source with an emission wavelength of 355 nm, the ground state of tris(bipyridine)ruthenium(II) molecules solved in acetonitrile was depleted and the spontaneous Raman scattering at 355 nm suppressed by nearly 50 %. Based on spectroscopic data retrieved from our experiment, we modeled the Raman image of a scattering center in order to demonstrate the applicability of this effect for superresolution Raman microscopy. PMID:27607677

  11. Depletion of Inositol Polyphosphate 4-Phosphatase II Suppresses Callosal Axon Formation in the Developing Mice

    PubMed Central

    Ji, Liting; Kim, Nam-Ho; Huh, Sung-Oh; Rhee, Hae Jin

    2016-01-01

    The corpus callosum is a bundle of nerve fibers that connects the two cerebral hemispheres and is essential for coordinated transmission of information between them. Disruption of early stages of callosal development can cause agenesis of the corpus callosum (AgCC), including both complete and partial callosal absence, causing mild to severe cognitive impairment. Despite extensive studies, the etiology of AgCC remains to be clarified due to the complicated mechanism involved in generating AgCC. The biological function of PI3K signaling including phosphatidylinositol-3,4,5-trisphosphate is well established in diverse biochemical processes including axon and dendrite morphogenesis, but the function of the closely related phosphatidylinositol-3,4,-bisphosphate (PI(3,4)P2) signaling, particularly in the nervous system, is largely unknown. Here, we provide the first report on the role of inositol polyphosphate 4-phosphatase II (INPP4B), a PI(3,4)P2 metabolizing 4-phosphatase in the regulation of callosal axon formation. Depleting INPP4B by in utero electroporation suppressed medially directed callosal axon formation. Moreover, depletion of INPP4B significantly attenuated formation of Satb2-positive pyramidal neurons and axon polarization in cortical neurons during cortical development. Taken together, these data suggest that INPP4B plays a role in the regulating callosal axon formation by controlling axon polarization and the Satb2-positive pyramidal neuron population. Dysregulation of INPP4B during cortical development may be implicated in the generation of partial AgCC. PMID:27109423

  12. Stress from Nucleotide Depletion Activates the Transcriptional Regulator HEXIM1 to Suppress Melanoma.

    PubMed

    Tan, Justin L; Fogley, Rachel D; Flynn, Ryan A; Ablain, Julien; Yang, Song; Saint-André, Violaine; Fan, Zi Peng; Do, Brian T; Laga, Alvaro C; Fujinaga, Koh; Santoriello, Cristina; Greer, Celeste B; Kim, Yoon Jung; Clohessy, John G; Bothmer, Anne; Pandell, Nicole; Avagyan, Serine; Brogie, John E; van Rooijen, Ellen; Hagedorn, Elliott J; Shyh-Chang, Ng; White, Richard M; Price, David H; Pandolfi, Pier Paolo; Peterlin, B Matija; Zhou, Yi; Kim, Tae Hoon; Asara, John M; Chang, Howard Y; Young, Richard A; Zon, Leonard I

    2016-04-01

    Studying cancer metabolism gives insight into tumorigenic survival mechanisms and susceptibilities. In melanoma, we identify HEXIM1, a transcription elongation regulator, as a melanoma tumor suppressor that responds to nucleotide stress. HEXIM1 expression is low in melanoma. Its overexpression in a zebrafish melanoma model suppresses cancer formation, while its inactivation accelerates tumor onset in vivo. Knockdown of HEXIM1 rescues zebrafish neural crest defects and human melanoma proliferation defects that arise from nucleotide depletion. Under nucleotide stress, HEXIM1 is induced to form an inhibitory complex with P-TEFb, the kinase that initiates transcription elongation, to inhibit elongation at tumorigenic genes. The resulting alteration in gene expression also causes anti-tumorigenic RNAs to bind to and be stabilized by HEXIM1. HEXIM1 plays an important role in inhibiting cancer cell-specific gene transcription while also facilitating anti-cancer gene expression. Our study reveals an important role for HEXIM1 in coupling nucleotide metabolism with transcriptional regulation in melanoma. PMID:27058786

  13. Suppression (but not reappraisal) impairs subsequent error detection: an ERP study of emotion regulation's resource-depleting effect.

    PubMed

    Wang, Yan; Yang, Lixia; Wang, Yan

    2014-01-01

    Past event-related potentials (ERPs) research shows that, after exerting effortful emotion inhibition, the neural correlates of performance monitoring (e.g. error-related negativity) were weakened. An undetermined issue is whether all forms of emotion regulation uniformly impair later performance monitoring. The present study compared the cognitive consequences of two emotion regulation strategies, namely suppression and reappraisal. Participants were instructed to suppress their emotions while watching a sad movie, or to adopt a neutral and objective attitude toward the movie, or to just watch the movie carefully. Then after a mood scale, all participants completed an ostensibly unrelated Stroop task, during which ERPs (i.e. error-related negativity (ERN), post-error positivity (Pe) and N450) were obtained. Reappraisal group successfully decreased their sad emotion, relative to the other two groups. Compared with participants in the control group and the reappraisal group, those who suppressed their emotions during the sad movie showed reduced ERN after error commission. Participants in the suppression group also made more errors in incongruent Stroop trials than the other two groups. There were no significant main effects or interactions of group for reaction time, Pe and N450. Results suggest that reappraisal is both more effective and less resource-depleting than suppression. PMID:24777113

  14. Iron depletion suppresses mTORC1-directed signalling in intestinal Caco-2 cells via induction of REDD1

    PubMed Central

    Watson, Ailsa; Lipina, Christopher; McArdle, Harry J.; Taylor, Peter M.; Hundal, Harinder S.

    2016-01-01

    Iron is an indispensable micronutrient that regulates many aspects of cell function, including growth and proliferation. These processes are critically dependent upon signalling via the mammalian or mechanistic target of rapamycin complex 1 (mTORC1). Herein, we test whether iron depletion induced by cell incubation with the iron chelator, deferoxamine (DFO), mediates its effects on cell growth through mTORC1-directed signalling and protein synthesis. We have used Caco-2 cells, a well-established in vitro model of human intestinal epithelia. Iron depletion increased expression of iron-regulated proteins (TfR, transferrin receptor and DMT1, divalent metal transporter, as predicted, but it also promoted a marked reduction in growth and proliferation of Caco-2 cells. This was strongly associated with suppressed mTORC1 signalling, as judged by reduced phosphorylation of mTOR substrates, S6K1 and 4E-BP1, and diminished protein synthesis. The reduction in mTORC1 signalling was tightly coupled with increased expression and accumulation of REDD1 (regulated in DNA damage and development 1) and reduced phosphorylation of Akt and TSC2. The increase in REDD1 abundance was rapidly reversed upon iron repletion of cells but was also attenuated by inhibitors of gene transcription, protein phosphatase 2A (PP2A) and by REDD1 siRNA — strategies that also antagonised the loss in mTORC1 signalling associated with iron depletion. Our findings implicate REDD1 and PP2A as crucial regulators of mTORC1 activity in iron-depleted cells and indicate that their modulation may help mitigate atrophy of the intestinal mucosa that may occur in response to iron deficiency. PMID:26827808

  15. Iron depletion suppresses mTORC1-directed signalling in intestinal Caco-2 cells via induction of REDD1.

    PubMed

    Watson, Ailsa; Lipina, Christopher; McArdle, Harry J; Taylor, Peter M; Hundal, Harinder S

    2016-05-01

    Iron is an indispensable micronutrient that regulates many aspects of cell function, including growth and proliferation. These processes are critically dependent upon signalling via the mammalian or mechanistic target of rapamycin complex 1 (mTORC1). Herein, we test whether iron depletion induced by cell incubation with the iron chelator, deferoxamine (DFO), mediates its effects on cell growth through mTORC1-directed signalling and protein synthesis. We have used Caco-2 cells, a well-established in vitro model of human intestinal epithelia. Iron depletion increased expression of iron-regulated proteins (TfR, transferrin receptor and DMT1, divalent metal transporter, as predicted, but it also promoted a marked reduction in growth and proliferation of Caco-2 cells. This was strongly associated with suppressed mTORC1 signalling, as judged by reduced phosphorylation of mTOR substrates, S6K1 and 4E-BP1, and diminished protein synthesis. The reduction in mTORC1 signalling was tightly coupled with increased expression and accumulation of REDD1 (regulated in DNA damage and development 1) and reduced phosphorylation of Akt and TSC2. The increase in REDD1 abundance was rapidly reversed upon iron repletion of cells but was also attenuated by inhibitors of gene transcription, protein phosphatase 2A (PP2A) and by REDD1 siRNA--strategies that also antagonised the loss in mTORC1 signalling associated with iron depletion. Our findings implicate REDD1 and PP2A as crucial regulators of mTORC1 activity in iron-depleted cells and indicate that their modulation may help mitigate atrophy of the intestinal mucosa that may occur in response to iron deficiency. PMID:26827808

  16. RALBP1/RLIP76 depletion in mice suppresses tumor growth by inhibiting tumor neovascularization

    PubMed Central

    Lee, Seunghyung; Wurtzel, Jeremy G.T.; Singhal, Sharad S.; Awasthi, Sanjay; Goldfinger, Lawrence E.

    2012-01-01

    RalBP1/RLIP76 is a widely expressed multifunctional protein that binds the Ral and R-Ras small GTPases. In the mouse, RLIP76 is non-essential but its depletion or blockade promotes tumorigenesis and heightens the sensitivity of normal and tumor cells to radiation and cytotoxic drugs. However, its pathobiological functions which support tumorigenesis are not well understood. Here we show that RLIP76 is required for angiogenesis and for efficient neovascularization of primary solid tumors. Tumor growth from implanted melanoma or carcinoma cells was blunted in RLIP76−/− mice. An X-ray microCT-based method to model tumor vascular structures revealed defects in both the extent and form of tumor angiogenesis in RLIP76−/− mice. Specifically, tumor vascular volumes were diminished and vessels were fewer in number, shorter, and narrower in RLIP76−/− mice than in wild-type mice. Moreover, we found that angiogenesis was blunted in mutant mice in the absence of tumor cells, with endothelial cells isolated from these animals exhibiting defects in migration, proliferation and cord formation in vitro. Taken together, our results establish that RLIP76 is required for efficient endothelial cell function and angiogenesis in solid tumors. PMID:22902412

  17. Zinc L-carnosine protects colonic mucosal injury through induction of heat shock protein 72 and suppression of NF-kappaB activation.

    PubMed

    Odashima, Masaru; Otaka, Michiro; Jin, Mario; Wada, Isao; Horikawa, Youhei; Matsuhashi, Tamotsu; Ohba, Reina; Hatakeyama, Natsumi; Oyake, Jinko; Watanabe, Sumio

    2006-11-10

    In this study, we investigated the effects of zinc L-carnosine, an anti-ulcer drug, on acetic acid-induced colonic mucosal injury and the correlation of these effects with expression of 72-kDa heat shock proteins (HSP72) and nuclear factor kappa B (NF-kappaB) activation in rat colonic mucosa in vivo. After intrarectal administration of zinc L-carnosine, the rats received intrarectal infusion of 5% acetic acid (1 ml). The colonic mucosal damage was evaluated by macroscopic assessments 24 h after the intrarectal infusion of acetic acid. Expression of HSP72 in rat colonic mucosa was evaluated by Western blot analysis before and after zinc L-carnosine administration. NF-kappaB activation was evaluated by electrophoretic mobility shift assays (EMSA). Zinc L-carnosine inhibited visible damage in rat colonic mucosa by acetic acid. Expression of HSP72 was significantly increased at 6 h after zinc L-carnosine administration. Furthermore, NF-kappaB activation in colonic mucosa was suppressed 6 h after zinc L-carnosine treatment. These results suggested that zinc L-carnosine protects the colonic mucosa against acetic acid by induction of HSP72 and suppression of NF-kappaB activation and zinc L-carnosine may be a novel therapeutic agent for the therapy of inflammatory bowel disease. PMID:16949620

  18. Suppression of Induced microRNA-15b Prevents Rapid Loss of Cardiac Function in a Dicer Depleted Model of Cardiac Dysfunction

    PubMed Central

    Gnyawali, Surya C.; Khanna, Savita; He, Guanglong; Pfeiffer, Douglas; Zweier, Jay L.; Sen, Chandan K.

    2013-01-01

    Background Dicer endonuclease, critical for maturation of miRNAs, is depleted in certain forms of cardiomyopathy which results in differential expression of certain microRNAs. We sought to elucidate the mechanisms underlying the rapid loss of cardiac function following cardiac-specific Dicer depletion in adult mice. Results Conditional Dicer deletion in the adult murine myocardium demonstrated compromised heart function, mitochondrial dysfunction and oxidant stress. Elevated miR-15b was observed as an early response to Dicer depletion and was found to silence Pim-1 kinase, a protein responsible for maintaining mitochondrial integrity and function. Anti-miRNA based suppression of induced miRNA-15b rescued the function of Dicer-depleted adult heart and attenuated hypertrophy. Conclusions Anti-miRNA based suppression of inducible miRNA-15b can prevent rapid loss of cardiac function in a Dicer-depleted adult heart and can be a key approach worthy of therapeutic consideration. PMID:23840532

  19. The RNA binding KH domain of Spoonbill depletes pathogenic non-coding spinocerebellar ataxia 8 transcripts and suppresses neurodegeneration in Drosophila.

    PubMed

    Tripathi, Bipin K; Surabhi, Satya; Bhaskar, Pradeep K; Mukherjee, Ashim; Mutsuddi, Mousumi

    2016-09-01

    Spinocerebellar ataxia 8 (SCA8) pathogenesis is a resultant of gain-of-function machinery that primarily results at the RNA level. It has been reported that expanded non-coding CTG trinucleotide repeat in the ATXN8OS transcripts leads to SCA8 coupled neurodegeneration. Targeted depletion of pathogenic SCA8 transcripts is a viable therapeutic approach. In this report we have focused on the suppression of toxic RNA gain-of-function associated with SCA8. We report suppression of SCA8 associated neurodegeneration by KH RNA binding domain of Spoonbill. KH domain suppresses pathogenic SCA8 associated phenotype in adult flies. Ectopic expression of KH domain leads to massive reduction in the number and size of SCA8 RNA foci. We show that Spoonbill interacts with toxic SCA8 transcripts via its KH domain and promotes its depletion. Till date, no attempts have been made for therapeutic intervention of SCA8 pathogenesis. Further characterization of Spoonbill KH domain may aid us in designing peptide based therapeutics for SCA8 associated neurodegeneration. PMID:27302466

  20. Innate Lymphoid Cells Are Depleted Irreversibly during Acute HIV-1 Infection in the Absence of Viral Suppression.

    PubMed

    Kløverpris, Henrik N; Kazer, Samuel W; Mjösberg, Jenny; Mabuka, Jenniffer M; Wellmann, Amanda; Ndhlovu, Zaza; Yadon, Marisa C; Nhamoyebonde, Shepherd; Muenchhoff, Maximilian; Simoni, Yannick; Andersson, Frank; Kuhn, Warren; Garrett, Nigel; Burgers, Wendy A; Kamya, Philomena; Pretorius, Karyn; Dong, Krista; Moodley, Amber; Newell, Evan W; Kasprowicz, Victoria; Abdool Karim, Salim S; Goulder, Philip; Shalek, Alex K; Walker, Bruce D; Ndung'u, Thumbi; Leslie, Alasdair

    2016-02-16

    Innate lymphoid cells (ILCs) play a central role in the response to infection by secreting cytokines crucial for immune regulation, tissue homeostasis, and repair. Although dysregulation of these systems is central to pathology, the impact of HIV-1 on ILCs remains unknown. We found that human blood ILCs were severely depleted during acute viremic HIV-1 infection and that ILC numbers did not recover after resolution of peak viremia. ILC numbers were preserved by antiretroviral therapy (ART), but only if initiated during acute infection. Transcriptional profiling during the acute phase revealed upregulation of genes associated with cell death, temporally linked with a strong IFN acute-phase response and evidence of gut barrier breakdown. We found no evidence of tissue redistribution in chronic disease and remaining circulating ILCs were activated but not apoptotic. These data provide a potential mechanistic link between acute HIV-1 infection, lymphoid tissue breakdown, and persistent immune dysfunction. PMID:26850658

  1. Overexpression of CIP2A is an independent prognostic indicator in nasopharyngeal carcinoma and its depletion suppresses cell proliferation and tumor growth

    PubMed Central

    2014-01-01

    Background Cancerous inhibitor of protein phosphatase 2A (CIP2A) is an oncoprotein that acts as a prognostic marker for several human malignancies. In this study, we investigated the clinical significance of CIP2A and its function in nasopharyngeal carcinoma (NPC). Methods Quantitative RT-PCR, western blot, and immunohistochemistry analyses were used to quantify CIP2A expression in NPC cell lines and clinical samples. Kaplan-Meier curves were used to estimate the association between CIP2A expression and patient survival. The functional role of CIP2A in NPC cell lines was evaluated by small interfering RNA-mediated depletion of the protein followed by analyses of cell proliferation and xenograft growth. Results CIP2A levels were upregulated in NPC cell lines and clinical samples at both the mRNA and protein levels (P < 0.01). Patients with high CIP2A expression had poorer overall survival (HR, 1.98; 95% CI, 1.16-3.34; P = 0.01) and poorer disease-free survival (HR, 1.68; 95% CI, 1.07-2.62; P = 0.02) rates than patients with low CIP2A expression. In addition, CIP2A expression status was an independent prognostic indicator for NPC patients. The depletion of CIP2A expression inhibited c-Myc protein expression in NPC cell lines, suppressed cell viability, colony formation, and anchorage-independent growth in vitro, and inhibited xenograft tumor growth in vivo. Conclusions Our data demonstrate that high CIP2A expression in patients was associated with poor survival in NPC, and depletion of CIP2A expression inhibited NPC cell proliferation and tumor growth. Thus, these results warrant further investigation of CIP2A as a novel therapeutic target for the treatment of NPC. PMID:24884612

  2. Suppression of HPV E6 and E7 expression by BAF53 depletion in cervical cancer cells

    SciTech Connect

    Lee, Kiwon; Lee, Ah-Young; Kwon, Yunhee Kim; Kwon, Hyockman

    2011-08-26

    Highlights: {yields} Integration of HPV into host genome critical for activation of E6 and E7 oncogenes. {yields} BAF53 is essential for higher-order chromatin structure. {yields} BAF53 knockdown suppresses E6 and E7 from HPV integrants, but not from episomal HPVs. {yields} BAF53 knockdown decreases H3K9Ac and H4K12Ac on P105 promoter of integrated HPV 18. {yields} BAF53 knockdown restores the p53-dependent signaling pathway in HeLa and SiHa cells. -- Abstract: Deregulation of the expression of human papillomavirus (HPV) oncogenes E6 and E7 plays a pivotal role in cervical carcinogenesis because the E6 and E7 proteins neutralize p53 and Rb tumor suppressor pathways, respectively. In approximately 90% of all cervical carcinomas, HPVs are found to be integrated into the host genome. Following integration, the core-enhancer element and P105 promoter that control expression of E6 and E7 adopt a chromatin structure that is different from that of episomal HPV, and this has been proposed to contribute to activation of E6 and E7 expression. However, the molecular basis underlying this chromatin structural change remains unknown. Previously, BAF53 has been shown to be essential for the integrity of higher-order chromatin structure and interchromosomal interactions. Here, we examined whether BAF53 is required for activated expression of E6 and E7 genes. We found that BAF53 knockdown led to suppression of expression of E6 and E7 genes from HPV integrants in cervical carcinoma cell lines HeLa and SiHa. Conversely, expression of transiently transfected HPV18-LCR-Luciferase was not suppressed by BAF53 knockdown. The level of the active histone marks H3K9Ac and H4K12Ac on the P105 promoter of integrated HPV 18 was decreased in BAF53 knockdown cells. BAF53 knockdown restored the p53-dependent signaling pathway in HeLa and SiHa cells. These results suggest that activated expression of the E6 and E7 genes of integrated HPV is dependent on BAF53-dependent higher-order chromatin

  3. Partial mitochondrial inhibition causes striatal dopamine release suppression and medium spiny neuron depolarization via H2O2 elevation, not ATP depletion.

    PubMed

    Bao, Li; Avshalumov, Marat V; Rice, Margaret E

    2005-10-26

    Mitochondrial dysfunction is a potential causal factor in Parkinson's disease. We show here that acute exposure to the mitochondrial complex I inhibitor rotenone (30-100 nM; 30 min) causes concentration-dependent suppression of single-pulse evoked dopamine (DA) release monitored in real time with carbon-fiber microelectrodes in guinea pig striatal slices, with no effect on DA content. Suppression of DA release was prevented by the sulfonylurea glibenclamide, implicating ATP-sensitive K+ (KATP) channels; however, tissue ATP was unaltered. Because KATP channels can be activated by hydrogen peroxide (H2O2), as well as by low ATP, we examined the involvement of rotenone-enhanced H2O2 generation. Confirming an essential role for H2O2, the inhibition of DA release by rotenone was prevented by catalase, a peroxide-scavenging enzyme. Striatal H2O2 generation during rotenone exposure was examined in individual medium spiny neurons using fluorescence imaging with dichlorofluorescein (DCF). An increase in intracellular H2O2 levels followed a similar time course to that of DA release suppression and was accompanied by cell membrane depolarization, decreased input resistance, and increased excitability. Extracellular catalase markedly attenuated the increase in DCF fluorescence and prevented rotenone-induced effects on membrane properties; membrane changes were also largely prevented by flufenamic acid, a blocker of transient receptor potential (TRP) channels. Thus, partial mitochondrial inhibition can cause functional DA denervation via H2O2 and KATP channels, without DA or ATP depletion. Furthermore, amplified H2O2 levels and TRP channel activation in striatal spiny neurons indicate potential sources of damage in these cells. Overall, these novel factors could contribute to parkinsonian motor deficits and neuronal degeneration caused by mitochondrial dysfunction. PMID:16251452

  4. Inhibition of angiogenesis and tumor growth in the brain. Suppression of endothelial cell turnover by penicillamine and the depletion of copper, an angiogenic cofactor.

    PubMed Central

    Brem, S. S.; Zagzag, D.; Tsanaclis, A. M.; Gately, S.; Elkouby, M. P.; Brien, S. E.

    1990-01-01

    Microvascular proliferation, a hallmark of malignant brain tumors, represents an attractive target of anticancer research, especially because of the quiescent nonproliferative endothelium of the normal brain. Cerebral neoplasms sequester copper, a trace metal that modulates angiogenesis. Using a rabbit brain tumor model, normocupremic animals developed large vascularized VX2 carcinomas. By contrast, small, circumscribed, relatively avascular tumors were found in the brains of rabbits copper-depleted by diet and penicillamine treatment (CDPT). The CDPT rabbits showed a significant decrease in serum copper, copper staining of tumor cell nuclei, microvascular density, the tumor volume, endothelial cell turnover, and an increase in the vascular permeability (breakdown of the blood-brain barrier), as well as peritumoral brain edema. In non-tumor-bearing animals, CDPT did not alter the vascular permeability or the brain water content. CDPT also inhibited the intracerebral growth of the 9L gliosarcoma in F-344 rats, with a similar increase of the peritumoral vascular permeability and the brain water content. CDPT failed to inhibit tumor growth and the vascularization of the VX2 carcinoma in the thigh muscle or the metastases to the lung, findings that may reflect regional differences in the responsiveness of the endothelium, the distribution of copper, or the activity of cuproenzymes. Metabolic and pharmacologic withdrawal of copper suppresses intracerebral tumor angiogenesis; angiosuppression is a novel biologic response modifier for the in situ control of tumor growth in the brain. Images Figure 2 Figure 4 Figure 5 Figure 6 Figure 8 Figure 10 Figure 12 Figure 15 Figure 16 PMID:1700617

  5. LOW OZONE-DEPLETING HALOCARBONS AS TOTAL-FLOOD AGENTS: VOLUME 2. LABORATORY-SCALE FIRE SUPPRESSION AND EXPLOSION PREVENTION TESTING

    EPA Science Inventory

    The report gives results from (1) flame suppression testing of potential Halon-1301 (CF3Br) replacement chemicals in a laboratory cup burner using n-heptane fuel and (2) explosion prevention (inertion) testing in a small-scale explosion sphere using propane and methane as fuels. ...

  6. Cholesterol depletion induces autophagy

    SciTech Connect

    Cheng, Jinglei; Ohsaki, Yuki; Tauchi-Sato, Kumi; Fujita, Akikazu; Fujimoto, Toyoshi . E-mail: tfujimot@med.nagoya-u.ac.jp

    2006-12-08

    Autophagy is a mechanism to digest cells' own components, and its importance in many physiological and pathological processes is being recognized. But the molecular mechanism that regulates autophagy is not understood in detail. In the present study, we found that cholesterol depletion induces macroautophagy. The cellular cholesterol in human fibroblasts was depleted either acutely using 5 mM methyl-{beta}-cyclodextrin or 10-20 {mu}g/ml nystatin for 1 h, or metabolically by 20 {mu}M mevastatin and 200 {mu}M mevalonolactone along with 10% lipoprotein-deficient serum for 2-3 days. By any of these protocols, marked increase of LC3-II was detected by immunoblotting and by immunofluorescence microscopy, and the increase was more extensive than that caused by amino acid starvation, i.e., incubation in Hanks' solution for several hours. The induction of autophagic vacuoles by cholesterol depletion was also observed in other cell types, and the LC3-positive membranes were often seen as long tubules, >50 {mu}m in length. The increase of LC3-II by methyl-{beta}-cyclodextrin was suppressed by phosphatidylinositol 3-kinase inhibitors and was accompanied by dephosphorylation of mammalian target of rapamycin. By electron microscopy, autophagic vacuoles induced by cholesterol depletion were indistinguishable from those seen after amino acid starvation. These results demonstrate that a decrease in cholesterol activates autophagy by a phosphatidylinositol 3-kinase-dependent mechanism.

  7. DEPLETED URANIUM TECHNICAL WORK

    EPA Science Inventory

    The Depleted Uranium Technical Work is designed to convey available information and knowledge about depleted uranium to EPA Remedial Project Managers, On-Scene Coordinators, contractors, and other Agency managers involved with the remediation of sites contaminated with this mater...

  8. Water Depletion Threatens Agriculture

    NASA Astrophysics Data System (ADS)

    Brauman, K. A.; Richter, B. D.; Postel, S.; Floerke, M.; Malsy, M.

    2014-12-01

    Irrigated agriculture is the human activity that has by far the largest impact on water, constituting 85% of global water consumption and 67% of global water withdrawals. Much of this water use occurs in places where water depletion, the ratio of water consumption to water availability, exceeds 75% for at least one month of the year. Although only 17% of global watershed area experiences depletion at this level or more, nearly 30% of total cropland and 60% of irrigated cropland are found in these depleted watersheds. Staple crops are particularly at risk, with 75% of global irrigated wheat production and 65% of irrigated maize production found in watersheds that are at least seasonally depleted. Of importance to textile production, 75% of cotton production occurs in the same watersheds. For crop production in depleted watersheds, we find that one half to two-thirds of production occurs in watersheds that have not just seasonal but annual water shortages, suggesting that re-distributing water supply over the course of the year cannot be an effective solution to shortage. We explore the degree to which irrigated production in depleted watersheds reflects limitations in supply, a byproduct of the need for irrigation in perennially or seasonally dry landscapes, and identify heavy irrigation consumption that leads to watershed depletion in more humid climates. For watersheds that are not depleted, we evaluate the potential impact of an increase in irrigated production. Finally, we evaluate the benefits of irrigated agriculture in depleted and non-depleted watersheds, quantifying the fraction of irrigated production going to food production, animal feed, and biofuels.

  9. Halo Star Lithium Depletion

    SciTech Connect

    Pinsonneault, M. H.; Walker, T. P.; Steigman, G.; Narayanan, Vijay K.

    1999-12-10

    The depletion of lithium during the pre-main-sequence and main-sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. Previous work has indicated a wide range of possible depletion factors, ranging from minimal in standard (nonrotating) stellar models to as much as an order of magnitude in models that include rotational mixing. Recent progress in the study of the angular momentum evolution of low-mass stars permits the construction of theoretical models capable of reproducing the angular momentum evolution of low-mass open cluster stars. The distribution of initial angular momenta can be inferred from stellar rotation data in young open clusters. In this paper we report on the application of these models to the study of lithium depletion in main-sequence halo stars. A range of initial angular momenta produces a range of lithium depletion factors on the main sequence. Using the distribution of initial conditions inferred from young open clusters leads to a well-defined halo lithium plateau with modest scatter and a small population of outliers. The mass-dependent angular momentum loss law inferred from open cluster studies produces a nearly flat plateau, unlike previous models that exhibited a downward curvature for hotter temperatures in the 7Li-Teff plane. The overall depletion factor for the plateau stars is sensitive primarily to the solar initial angular momentum used in the calibration for the mixing diffusion coefficients. Uncertainties remain in the treatment of the internal angular momentum transport in the models, and the potential impact of these uncertainties on our results is discussed. The 6Li/7Li depletion ratio is also examined. We find that the dispersion in the plateau and the 6Li/7Li depletion ratio scale with the absolute 7Li depletion in the plateau, and we use observational data to set bounds on the 7Li depletion in main-sequence halo

  10. Biomedical consequences of ozone depletion

    NASA Astrophysics Data System (ADS)

    Coohill, Thomas P.

    1994-07-01

    It is widely agreed that a portion of the earth's protective stratospheric ozone layer is being depleted. The major effect of this ozone loss will be an increase in the amount of ultraviolet radiation (UV reaching the biosphere. This increase will be completely contained within the UVB (290nm - 320nm). It is imperative that assessments be made of the effects of this additional UVB on living organisms. This requires a detailed knowledge of the UVB photobiology of these life forms. One analytical technique to aid in the approximations is the construction of UV action spectra for such important biological end-points as human skin cancer, cataracts, immune suppression; plant photosynthesis and crop yields; and aquatic organism responses to UVB, especially the phytoplankton. Combining these action spectra with the known solar spectrum (and estimates for various ozone depletion scenarios) can give rise to a series of effectiveness spectra for these parameters. This manuscript gives a first approximation, rough estimate, for the effectiveness spectra for some of these bioresponses, and a series of crude temporary values for how a 10% ozone loss would affect the above end-points. These are not intended to masquerade as final answers, but rather, to serve as beginning attempts for a process which should be continually refined. It is hoped that these estimates will be of some limited use to agencies, such as government and industry, that have to plan now for changes in human activities that might alter future atmospheric chemistry in a beneficial manner.

  11. Expression of Hsp72 in lymphocytes in patients with febrile convulsion.

    PubMed

    Lin, Lung-Chang; Chen, Hsiang-Wen; Yang, Rei-Cheng

    2005-03-01

    The pathophysiology of febrile convulsion, the most common childhood neurologic disease, remains unclear. In this study, we investigated what role a heat shock protein plays in this disease. We enrolled eight boys and two girls with febrile convulsion and 10 age-matched healthy controls. We did a biosynthetic evaluation of both groups by separating lymphocytes and measuring the expression of heat shock protein 72 before and after heat shock treatment. Before the treatment, both groups were found to have small amounts of constitutive heat shock protein 72. Afterwards, its expression increased in both groups, and no statistical difference was found between the increases in the two groups. In addition, there was no obvious difference in the susceptibility to produce heat shock proteins. However, the febrile convulsion group was found to have a significant decrease in phosphorylation of heat shock protein 72. These results suggest the possible involvement of post-translational modification of heat shock proteins, most likely phosphorylation, in the pathogenesis of febrile convulsion. PMID:15875434

  12. Depleted uranium disposal options.

    SciTech Connect

    Biwer, B. M.; Ranek, N. L.; Goldberg, M.; Avci, H. I.

    2000-04-01

    Depleted uranium hexafluoride (UF{sub 6}) has been produced in the United States since the 1940s as part of both the military program and the civilian nuclear energy program. The U.S. Department of Energy (DOE) is the agency responsible for managing most of the depleted UF{sub 6} that has been produced in the United States. The total quantity of depleted UF{sub 6} that DOE has to or will have to manage is approximately 700,000 Mg. Studies have been conducted to evaluate the various alternatives for managing this material. This paper evaluates and summarizes the alternative of disposal as low-level waste (LLW). Results of the analysis indicate that UF{sub 6} needs to be converted to a more stable form, such as U{sub 3}O{sub 8}, before disposal as LLW. Estimates of the environmental impacts of disposal in a dry environment are within the currently applicable standards and regulations. Of the currently operating LLW disposal facilities, available information indicates that either of two DOE facilities--the Hanford Site or the Nevada Test Site--or a commercial facility--Envirocare of Utah--would be able to dispose of up to the entire DOE inventory of depleted UF{sub 6}.

  13. Revisiting Antarctic Ozone Depletion

    NASA Astrophysics Data System (ADS)

    Grooß, Jens-Uwe; Tritscher, Ines; Müller, Rolf

    2015-04-01

    Antarctic ozone depletion is known for almost three decades and it has been well settled that it is caused by chlorine catalysed ozone depletion inside the polar vortex. However, there are still some details, which need to be clarified. In particular, there is a current debate on the relative importance of liquid aerosol and crystalline NAT and ice particles for chlorine activation. Particles have a threefold impact on polar chlorine chemistry, temporary removal of HNO3 from the gas-phase (uptake), permanent removal of HNO3 from the atmosphere (denitrification), and chlorine activation through heterogeneous reactions. We have performed simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) employing a recently developed algorithm for saturation-dependent NAT nucleation for the Antarctic winters 2011 and 2012. The simulation results are compared with different satellite observations. With the help of these simulations, we investigate the role of the different processes responsible for chlorine activation and ozone depletion. Especially the sensitivity with respect to the particle type has been investigated. If temperatures are artificially forced to only allow cold binary liquid aerosol, the simulation still shows significant chlorine activation and ozone depletion. The results of the 3-D Chemical Transport Model CLaMS simulations differ from purely Lagrangian longtime trajectory box model simulations which indicates the importance of mixing processes.

  14. Inositol Depletion Restores Vesicle Transport in Yeast Phospholipid Flippase Mutants

    PubMed Central

    Yamagami, Kanako; Yamamoto, Takaharu; Sakai, Shota; Mioka, Tetsuo; Sano, Takamitsu; Igarashi, Yasuyuki; Tanaka, Kazuma

    2015-01-01

    In eukaryotic cells, type 4 P-type ATPases function as phospholipid flippases, which translocate phospholipids from the exoplasmic leaflet to the cytoplasmic leaflet of the lipid bilayer. Flippases function in the formation of transport vesicles, but the mechanism remains unknown. Here, we isolate an arrestin-related trafficking adaptor, ART5, as a multicopy suppressor of the growth and endocytic recycling defects of flippase mutants in budding yeast. Consistent with a previous report that Art5p downregulates the inositol transporter Itr1p by endocytosis, we found that flippase mutations were also suppressed by the disruption of ITR1, as well as by depletion of inositol from the culture medium. Interestingly, inositol depletion suppressed the defects in all five flippase mutants. Inositol depletion also partially restored the formation of secretory vesicles in a flippase mutant. Inositol depletion caused changes in lipid composition, including a decrease in phosphatidylinositol and an increase in phosphatidylserine. A reduction in phosphatidylinositol levels caused by partially depleting the phosphatidylinositol synthase Pis1p also suppressed a flippase mutation. These results suggest that inositol depletion changes the lipid composition of the endosomal/TGN membranes, which results in vesicle formation from these membranes in the absence of flippases. PMID:25781026

  15. Heat Shock Protein 72 Enhances Autophagy as a Protective Mechanism in Lipopolysaccharide-Induced Peritonitis in Rats

    PubMed Central

    Li, Shu; Zhou, Yi; Fan, Jinjin; Cao, Shirong; Cao, Tao; Huang, Fengxian; Zhuang, Shougang; Wang, Yihan; Yu, Xueqing; Mao, Haiping

    2011-01-01

    Peritoneal dialysis–related peritonitis causes the denudation of mesothelial cells and, ultimately, membrane integrity alterations and peritoneal dysfunction. Because heat shock protein 72 (HSP72) confers protection against apoptosis and because autophagy mediates survival in response to cellular stresses, we examined whether autophagy contributes to HSP72-mediated cytoprotection in lipopolysaccharide (LPS)-induced peritonitis. Exposure of cultured peritoneal mesothelial cells to LPS resulted first in autophagy and later, apoptosis. Inhibition of autophagy by 3-methyladenine or Beclin-1 small-interfering RNA sensitized cells to apoptosis and abolished the antiapoptotic effect of HSP72, suggesting that autophagy activation acts as a prosurvival mechanism. Overexpression of HSP72 augmented autophagy through c-Jun N-terminal kinase (JNK) phosphorylation and Beclin-1 up-regulation. Suppression of JNK activity reversed HSP72-mediated Beclin-1 up-regulation and autophagy, indicating that HSP72-mediated autophagy is JNK dependent. In a rat model of LPS-associated peritonitis, autophagy occurred before apoptosis in peritoneum. Up-regulation of HSP72 by geranylgeranylacetone increased autophagy, inhibited apoptosis, and attenuated peritoneal injury, and these effects were blunted by down-regulation of HSP72 with quercetin. Additionally, blocking autophagy by chloroquine promoted apoptosis and aggravated LPS-associated peritoneal dysfunction. Thus, HSP72 protects peritoneum from LPS-induced mesothelial cells injury, at least in part by enhancing JNK activation–dependent autophagy and inhibiting apoptosis. These findings imply that HSP72 induction might be a potential therapy for peritonitis. PMID:22001349

  16. Ozone depletion by hydrofluorocarbons

    NASA Astrophysics Data System (ADS)

    Hurwitz, Margaret M.; Fleming, Eric L.; Newman, Paul A.; Li, Feng; Mlawer, Eli; Cady-Pereira, Karen; Bailey, Roshelle

    2015-10-01

    Atmospheric concentrations of hydrofluorocarbons (HFCs) are projected to increase considerably in the coming decades. Chemistry climate model simulations forced by current projections show that HFCs will impact the global atmosphere increasingly through 2050. As strong radiative forcers, HFCs increase tropospheric and stratospheric temperatures, thereby enhancing ozone-destroying catalytic cycles and modifying the atmospheric circulation. These changes lead to a weak depletion of stratospheric ozone. Simulations with the NASA Goddard Space Flight Center 2-D model show that HFC-125 is the most important contributor to HFC-related atmospheric change in 2050; its effects are comparable to the combined impacts of HFC-23, HFC-32, HFC-134a, and HFC-143a. Incorporating the interactions between chemistry, radiation, and dynamics, ozone depletion potentials (ODPs) for HFCs range from 0.39 × 10-3 to 30.0 × 10-3, approximately 100 times larger than previous ODP estimates which were based solely on chemical effects.

  17. Depleted uranium management alternatives

    SciTech Connect

    Hertzler, T.J.; Nishimoto, D.D.

    1994-08-01

    This report evaluates two management alternatives for Department of Energy depleted uranium: continued storage as uranium hexafluoride, and conversion to uranium metal and fabrication to shielding for spent nuclear fuel containers. The results will be used to compare the costs with other alternatives, such as disposal. Cost estimates for the continued storage alternative are based on a life-cycle of 27 years through the year 2020. Cost estimates for the recycle alternative are based on existing conversion process costs and Capital costs for fabricating the containers. Additionally, the recycle alternative accounts for costs associated with intermediate product resale and secondary waste disposal for materials generated during the conversion process.

  18. Tank depletion flow controller

    DOEpatents

    Georgeson, Melvin A.

    1976-10-26

    A flow control system includes two bubbler tubes installed at different levels within a tank containing such as radioactive liquid. As the tank is depleted, a differential pressure transmitter monitors pressure differences imparted by the two bubbler tubes at a remote, shielded location during uniform time intervals. At the end of each uniform interval, balance pots containing a dense liquid are valved together to equalize the pressures. The resulting sawtooth-shaped signal generated by the differential pressure transmitter is compared with a second sawtooth signal representing the desired flow rate during each time interval. Variations in the two signals are employed by a control instrument to regulate flow rate.

  19. Arginine depletion increases susceptibility to serious infections in preterm newborns

    PubMed Central

    Badurdeen, Shiraz; Mulongo, Musa; Berkley, James A.

    2015-01-01

    Preterm newborns are highly susceptible to bacterial infections. This susceptibility is regarded as being due to immaturity of multiple pathways of the immune system. However, it is unclear whether a mechanism that unifies these different, suppressed pathways exists. Here, we argue that the immune vulnerability of the preterm neonate is critically related to arginine depletion. Arginine, a “conditionally essential” amino acid, is depleted in acute catabolic states, including sepsis. Its metabolism is highly compartmentalized and regulated, including by arginase-mediated hydrolysis. Recent data suggest that arginase II-mediated arginine depletion is essential for the innate immune suppression that occurs in newborn models of bacterial challenge, impairing pathways critical for the immune response. Evidence that arginine depletion mediates protection from immune activation during first gut colonization suggests a regulatory role in controlling gut-derived pathogens. Clinical studies show that plasma arginine is depleted during sepsis. In keeping with animal studies, small clinical trials of L-arginine supplementation have shown benefit in reducing necrotizing enterocolitis in premature neonates. We propose a novel, broader hypothesis that arginine depletion during bacterial challenge is a key factor limiting the neonate's ability to mount an adequate immune response, contributing to the increased susceptibility to infections, particularly with respect to gut-derived sepsis. PMID:25360828

  20. Barium depletion in hollow cathode emitters

    NASA Astrophysics Data System (ADS)

    Polk, James E.; Mikellides, Ioannis G.; Capece, Angela M.; Katz, Ira

    2016-01-01

    Dispenser hollow cathodes rely on a consumable supply of Ba released by BaO-CaO-Al2O3 source material in the pores of a tungsten matrix to maintain a low work function surface. The examination of cathode emitters from long duration tests shows deposits of tungsten at the downstream end that appear to block the flow of Ba from the interior. In addition, a numerical model of Ba transport in the cathode plasma indicates that the Ba partial pressure in the insert may exceed the equilibrium vapor pressure of the dominant Ba-producing reaction, and it was postulated previously that this would suppress Ba loss in the upstream part of the emitter. New measurements of the Ba depletion depth from a cathode insert operated for 8200 h reveal that Ba loss is confined to a narrow region near the downstream end, confirming this hypothesis. The Ba transport model was modified to predict the depletion depth with time. A comparison of the calculated and measured depletion depths gives excellent qualitative agreement, and quantitative agreement was obtained assuming an insert temperature 70 °C lower than measured beginning-of-life values.

  1. Ozone Depletion by Hydrofluorocarbons

    NASA Astrophysics Data System (ADS)

    Hurwitz, M.; Fleming, E. L.; Newman, P. A.; Li, F.; Mlawer, E. J.; Cady-Pereira, K. E.; Bailey, R.

    2015-12-01

    Hydrofluorocarbons (HFCs) are second-generation replacements for the chlorofluorocarbons (CFCs), halons and other substances that caused the 'ozone hole'. Atmospheric concentrations of HFCs are projected to increase dramatically in the coming decades. Coupled chemistry-climate simulations forced by these projections show that HFCs will impact the global atmosphere in 2050. As strong radiative forcers, HFCs modulate atmospheric temperature, thereby changing ozone-destroying catalytic cycles and enhancing the stratospheric circulation. These changes lead to a weak depletion of stratospheric ozone. Sensitivity simulations with the NASA Goddard Space Flight Center (GSFC) 2D model show that HFC-125 is the most important contributor to atmospheric change in 2050, as compared with HFC-23, HFC-32, HFC-134a and HFC-143a. Incorporating the interactions between chemistry, radiation and dynamics, for a likely 2050 climate, ozone depletion potentials (ODPs) for HFCs range from 4.3x10-4 to 3.5x10-2; previously HFCs were assumed to have negligible ODPs since these species lack chlorine or bromine atoms. The ozone impacts of HFCs are further investigated with the Goddard Earth Observing System Chemistry-Climate Model (GEOSCCM). The GEOSCCM is a three-dimensional, fully coupled ocean-atmosphere model with interactive stratospheric chemistry. Sensitivity simulations in which CO2, CFC-11 and HCFC-22 are enhanced individually are used as proxies for the atmospheric response to the HFC concentrations expected by the mid-21st century. Sensitivity simulations provide quantitative estimates of the impacts of these greenhouse gases on global total ozone, and can be used to assess their effects on the recovery of Antarctic ozone.

  2. 12. VIEW OF DEPLETED URANIUM INGOT AND MOLDS. DEPLETED URANIUM ...

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

    12. VIEW OF DEPLETED URANIUM INGOT AND MOLDS. DEPLETED URANIUM CASTING OPERATIONS CEASED IN 1988. (11/14/57) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  3. Depleted Uranium in Repositories

    SciTech Connect

    Haire, M.J.; Croff, A.G.

    1997-12-31

    For uranium to be useful in most fission nuclear reactors, it must be enriched (i.e. the concentration of the fissile isotope 235U must be increased). Therefore, depleted uranium (DU)-uranium which has less than naturally occurring concentrations of 235U-is a co-product of the enrichment process. Four to six tons of DU exist for every ton of fresh light water reactor fuel. There were 407,006 MgU 407,000 metric tons (t) of DU stored on U.S. Department of Energy (DOE) sites as of July 1993. If this DU were to be declared surplus, converted to a stable oxide form, and emplaced in a near surface disposal facility, the costs are estimated to be several billion dollars. However, the U.S. Nuclear Regulatory Commission has stated that near surface disposal of large quantities of DU tails is not appropriate. Thus, there is the possibility that disposition via disposal will be in a deep geological repository. One alternative that may significantly reduce the cost of DU disposition is to use it beneficially. In fact, DOE has begun the Beneficial Uses of DU Project to identify large scale uses of DU and to encourage its reuse. Several beneficial uses, many of which involve applications in the repository per se or in managing the wastes to go into the repository, are discussed in this report.

  4. The Toxicity of Depleted Uranium

    PubMed Central

    Briner, Wayne

    2010-01-01

    Depleted uranium (DU) is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a clear and defined set of symptoms. Chronic low-dose, or subacute, exposure to depleted uranium alters the appearance of milestones in developing organisms. Adult animals that were exposed to depleted uranium during development display persistent alterations in behavior, even after cessation of depleted uranium exposure. Adult animals exposed to depleted uranium demonstrate altered behaviors and a variety of alterations to brain chemistry. Despite its reduced level of radioactivity evidence continues to accumulate that depleted uranium, if ingested, may pose a radiologic hazard. The current state of knowledge concerning DU is discussed. PMID:20195447

  5. Stratospheric ozone depletion

    PubMed Central

    Rowland, F. Sherwood

    2006-01-01

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290–320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime—the ‘Antarctic ozone hole’. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  6. Stratospheric ozone depletion.

    PubMed

    Rowland, F Sherwood

    2006-05-29

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290-320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime-the 'Antarctic ozone hole'. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  7. Tuning of depletion interaction in nanoparticle-surfactant systems

    SciTech Connect

    Ray, D. Aswal, V. K.

    2014-04-24

    The interaction of anionic silica nanoparticles (Ludox LS30) and non-ionic surfactants decaethylene glycol monododecylether (C12E10) without and with anionic sodium dodecyl sulfate (SDS) in aqueous electrolyte solution has been studied by small-angle neutron scattering (SANS). The measurements have been carried out for fixed concentrations of nanoparticle (1 wt%), surfactants (1 wt%) and electrolyte (0.1 M NaCl). Each of these nanoparticlesurfactant systems has been examined for different contrast conditions where individual components (nanoparticle or surfactant) are made visible. It is observed that the nanoparticle-C12E10 system leads to the depletion-induced aggregation of nanoparticles. The system however behaves very differently on addition of SDS where depletion interaction gets suppressed and aggregation of nanoparticles can be prevented. We show that C12E10 and SDS form mixed micelles and the charge on these micelles plays important role in tuning the depletion interaction.

  8. Ego depletion impairs implicit learning.

    PubMed

    Thompson, Kelsey R; Sanchez, Daniel J; Wesley, Abigail H; Reber, Paul J

    2014-01-01

    Implicit skill learning occurs incidentally and without conscious awareness of what is learned. However, the rate and effectiveness of learning may still be affected by decreased availability of central processing resources. Dual-task experiments have generally found impairments in implicit learning, however, these studies have also shown that certain characteristics of the secondary task (e.g., timing) can complicate the interpretation of these results. To avoid this problem, the current experiments used a novel method to impose resource constraints prior to engaging in skill learning. Ego depletion theory states that humans possess a limited store of cognitive resources that, when depleted, results in deficits in self-regulation and cognitive control. In a first experiment, we used a standard ego depletion manipulation prior to performance of the Serial Interception Sequence Learning (SISL) task. Depleted participants exhibited poorer test performance than did non-depleted controls, indicating that reducing available executive resources may adversely affect implicit sequence learning, expression of sequence knowledge, or both. In a second experiment, depletion was administered either prior to or after training. Participants who reported higher levels of depletion before or after training again showed less sequence-specific knowledge on the post-training assessment. However, the results did not allow for clear separation of ego depletion effects on learning versus subsequent sequence-specific performance. These results indicate that performance on an implicitly learned sequence can be impaired by a reduction in executive resources, in spite of learning taking place outside of awareness and without conscious intent. PMID:25275517

  9. Depleting depletion: Polymer swelling in poor solvent mixtures

    NASA Astrophysics Data System (ADS)

    Mukherji, Debashish; Marques, Carlos; Stuehn, Torsten; Kremer, Kurt

    A polymer collapses in a solvent when the solvent particles dislike monomers more than the repulsion between monomers. This leads to an effective attraction between monomers, also referred to as depletion induced attraction. This attraction is the key factor behind standard polymer collapse in poor solvents. Strikingly, even if a polymer exhibits poor solvent condition in two different solvents, it can also swell in mixtures of these two poor solvents. This collapse-swelling-collapse scenario is displayed by poly(methyl methacrylate) (PMMA) in aqueous alcohol. Using molecular dynamics simulations of a thermodynamically consistent generic model and theoretical arguments, we unveil the microscopic origin of this phenomenon. Our analysis suggests that a subtle interplay of the bulk solution properties and the local depletion forces reduces depletion effects, thus dictating polymer swelling in poor solvent mixtures.

  10. Fully depleted back illuminated CCD

    DOEpatents

    Holland, Stephen Edward

    2001-01-01

    A backside illuminated charge coupled device (CCD) is formed of a relatively thick high resistivity photon sensitive silicon substrate, with frontside electronic circuitry, and an optically transparent backside ohmic contact for applying a backside voltage which is at least sufficient to substantially fully deplete the substrate. A greater bias voltage which overdepletes the substrate may also be applied. One way of applying the bias voltage to the substrate is by physically connecting the voltage source to the ohmic contact. An alternate way of applying the bias voltage to the substrate is to physically connect the voltage source to the frontside of the substrate, at a point outside the depletion region. Thus both frontside and backside contacts can be used for backside biasing to fully deplete the substrate. Also, high resistivity gaps around the CCD channels and electrically floating channel stop regions can be provided in the CCD array around the CCD channels. The CCD array forms an imaging sensor useful in astronomy.

  11. Depletable externalities and Pigouvian taxation

    SciTech Connect

    Freeman, A.M. III

    1984-06-01

    In their book Baumol and Oates (The Theory of Environmental Policy: Externalities, Public Outlays, and the Quality of Life; Prentice-Hall, Englewood Cliffs, NJ (1975).) argue that whether an externality is depletable (private) or undepletable (public) is the key characteristic in determining the optimal pricing pattern. They argue that unlike the undepletable case a negative depletable externality requires not only a charge or tax on the generator of the externality but a payment or compensation to the victim in order to achieve Pareto optimality. It is shown that the key characteristic determining whether compensation of victims is required for efficiency is not the depletability of the externality but whether the victim can costlessly control or limit the amount of the damaging substance received. 6 references.

  12. Curcumin Suppresses Soluble Tau Dimers and Corrects Molecular Chaperone, Synaptic, and Behavioral Deficits in Aged Human Tau Transgenic Mice*

    PubMed Central

    Ma, Qiu-Lan; Zuo, Xiaohong; Yang, Fusheng; Ubeda, Oliver J.; Gant, Dana J.; Alaverdyan, Mher; Teng, Edmond; Hu, Shuxin; Chen, Ping-Ping; Maiti, Panchanan; Teter, Bruce; Cole, Greg M.; Frautschy, Sally A.

    2013-01-01

    The mechanisms underlying Tau-related synaptic and cognitive deficits and the interrelationships between Tau species, their clearance pathways, and synaptic impairments remain poorly understood. To gain insight into these mechanisms, we examined these interrelationships in aged non-mutant genomic human Tau mice, with established Tau pathology and neuron loss. We also examined how these interrelationships changed with an intervention by feeding mice either a control diet or one containing the brain permeable beta-amyloid and Tau aggregate binding molecule curcumin. Transgene-dependent elevations in soluble and insoluble phospho-Tau monomer and soluble Tau dimers accompanied deficits in behavior, hippocampal excitatory synaptic markers, and molecular chaperones (heat shock proteins (HSPs)) involved in Tau degradation and microtubule stability. In human Tau mice but not control mice, HSP70, HSP70/HSP72, and HSP90 were reduced in membrane-enriched fractions but not in cytosolic fractions. The synaptic proteins PSD95 and NR2B were reduced in dendritic fields and redistributed into perikarya, corresponding to changes observed by immunoblot. Curcumin selectively suppressed levels of soluble Tau dimers, but not of insoluble and monomeric phospho-Tau, while correcting behavioral, synaptic, and HSP deficits. Treatment increased PSD95 co-immunoprecipitating with NR2B and, independent of transgene, increased HSPs implicated in Tau clearance. It elevated HSP90 and HSC70 without increasing HSP mRNAs; that is, without induction of the heat shock response. Instead curcumin differentially impacted HSP90 client kinases, reducing Fyn without reducing Akt. In summary, curcumin reduced soluble Tau and elevated HSPs involved in Tau clearance, showing that even after tangles have formed, Tau-dependent behavioral and synaptic deficits can be corrected. PMID:23264626

  13. DOPAMINE DEPLETION SLOWS RETINAL TRANSMISSION

    EPA Science Inventory

    In male hooded rats, depletion of norepinephrine and dopamine by a-methyl-paratyrosine (AMT) significantly increased the latencies of early peaks in flash-evoked potentials recorded from the visual cortex, lateral geniculate nucleus, and optic tract. These effects were not produc...

  14. SCISAT to study ozone depletion

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    The Canadian Space Agency's SCISAT satellite began its mission to study the depletion of the ozone layer, following a successful launch on 12 August.The goal for the atmospheric chemistry experiment, which is SCISAT's mission, is to improve the scientific understanding of the complex chemical changes occurring in the upper atmosphere, particularly in the far north, according to Canada's Minister of Industry, Allan Rock.

  15. Ozone depletion, paradigms, and politics

    SciTech Connect

    Iman, R.L.

    1993-10-01

    The destruction of the Earth`s protective ozone layer is a prime environmental concern. Industry has responded to this environmental problem by: implementing conservation techniques to reduce the emission of ozone-depleting chemicals (ODCs); using alternative cleaning solvents that have lower ozone depletion potentials (ODPs); developing new, non-ozone-depleting solvents, such as terpenes; and developing low-residue soldering processes. This paper presents an overview of a joint testing program at Sandia and Motorola to evaluate a low-residue (no-clean) soldering process for printed wiring boards (PWBs). Such processes are in widespread use in commercial applications because they eliminate the cleaning operation. The goal of this testing program was to develop a data base that could be used to support changes in the mil-specs. In addition, a joint task force involving industry and the military has been formed to conduct a follow-up evaluation of low-residue processes that encompass the concerns of the tri-services. The goal of the task force is to gain final approval of the low-residue technology for use in military applications.

  16. Ozone Depletion from Nearby Supernovae

    NASA Technical Reports Server (NTRS)

    Gehrels, Neil; Laird, Claude M.; Jackman, Charles H.; Cannizzo, John K.; Mattson, Barbara J.; Chen, Wan; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    Estimates made in the 1970's indicated that a supernova occurring within tens of parsecs of Earth could have significant effects on the ozone layer. Since that time improved tools for detailed modeling of atmospheric chemistry have been developed to calculate ozone depletion, and advances have been made also in theoretical modeling of supernovae and of the resultant gamma ray spectra. In addition, one now has better knowledge of the occurrence rate of supernovae in the galaxy, and of the spatial distribution of progenitors to core-collapse supernovae. We report here the results of two-dimensional atmospheric model calculations that take as input the spectral energy distribution of a supernova, adopting various distances from Earth and various latitude impact angles. In separate simulations we calculate the ozone depletion due to both gamma rays and cosmic rays. We find that for the combined ozone depletion from these effects roughly to double the 'biologically active' UV flux received at the surface of the Earth, the supernova must occur at approximately or less than 8 parsecs.

  17. Issues in Stratospheric Ozone Depletion.

    NASA Astrophysics Data System (ADS)

    Lloyd, Steven Andrew

    Following the announcement of the discovery of the Antarctic ozone hole in 1985 there have arisen a multitude of questions pertaining to the nature and consequences of polar ozone depletion. This thesis addresses several of these specific questions, using both computer models of chemical kinetics and the Earth's radiation field as well as laboratory kinetic experiments. A coupled chemical kinetic-radiative numerical model was developed to assist in the analysis of in situ field measurements of several radical and neutral species in the polar and mid-latitude lower stratosphere. Modeling was used in the analysis of enhanced polar ClO, mid-latitude diurnal variation of ClO, and simultaneous measurements of OH, HO_2, H_2 O and O_3. Most importantly, such modeling was instrumental in establishing the link between the observed ClO and BrO concentrations in the Antarctic polar vortex and the observed rate of ozone depletion. The principal medical concern of stratospheric ozone depletion is that ozone loss will lead to the enhancement of ground-level UV-B radiation. Global ozone climatology (40^circS to 50^ circN latitude) was incorporated into a radiation field model to calculate the biologically accumulated dosage (BAD) of UV-B radiation, integrated over days, months, and years. The slope of the annual BAD as a function of latitude was found to correspond to epidemiological data for non-melanoma skin cancers for 30^circ -50^circN. Various ozone loss scenarios were investigated. It was found that a small ozone loss in the tropics can provide as much additional biologically effective UV-B as a much larger ozone loss at higher latitudes. Also, for ozone depletions of > 5%, the BAD of UV-B increases exponentially with decreasing ozone levels. An important key player in determining whether polar ozone depletion can propagate into the populated mid-latitudes is chlorine nitrate, ClONO_2 . As yet this molecule is only indirectly accounted for in computer models and field

  18. The Case of Ozone Depletion

    NASA Technical Reports Server (NTRS)

    Lambright, W. Henry

    2005-01-01

    While the National Aeronautics and Space Administration (NASA) is widely perceived as a space agency, since its inception NASA has had a mission dedicated to the home planet. Initially, this mission involved using space to better observe and predict weather and to enable worldwide communication. Meteorological and communication satellites showed the value of space for earthly endeavors in the 1960s. In 1972, NASA launched Landsat, and the era of earth-resource monitoring began. At the same time, in the late 1960s and early 1970s, the environmental movement swept throughout the United States and most industrialized countries. The first Earth Day event took place in 1970, and the government generally began to pay much more attention to issues of environmental quality. Mitigating pollution became an overriding objective for many agencies. NASA's existing mission to observe planet Earth was augmented in these years and directed more toward environmental quality. In the 1980s, NASA sought to plan and establish a new environmental effort that eventuated in the 1990s with the Earth Observing System (EOS). The Agency was able to make its initial mark via atmospheric monitoring, specifically ozone depletion. An important policy stimulus in many respects, ozone depletion spawned the Montreal Protocol of 1987 (the most significant international environmental treaty then in existence). It also was an issue critical to NASA's history that served as a bridge linking NASA's weather and land-resource satellites to NASA s concern for the global changes affecting the home planet. Significantly, as a global environmental problem, ozone depletion underscored the importance of NASA's ability to observe Earth from space. Moreover, the NASA management team's ability to apply large-scale research efforts and mobilize the talents of other agencies and the private sector illuminated its role as a lead agency capable of crossing organizational boundaries as well as the science-policy divide.

  19. "When the going gets tough, who keeps going?" Depletion sensitivity moderates the ego-depletion effect.

    PubMed

    Salmon, Stefanie J; Adriaanse, Marieke A; De Vet, Emely; Fennis, Bob M; De Ridder, Denise T D

    2014-01-01

    Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In three studies, we assessed individual differences in depletion sensitivity, and demonstrate that depletion sensitivity moderates ego-depletion effects. The Depletion Sensitivity Scale (DSS) was employed to assess depletion sensitivity. Study 1 employs the DSS to demonstrate that individual differences in sensitivity to ego-depletion exist. Study 2 shows moderate correlations of depletion sensitivity with related self-control concepts, indicating that these scales measure conceptually distinct constructs. Study 3 demonstrates that depletion sensitivity moderates the ego-depletion effect. Specifically, participants who are sensitive to depletion performed worse on a second self-control task, indicating a stronger ego-depletion effect, compared to participants less sensitive to depletion. PMID:25009523

  20. The 1988 Antarctic ozone depletion: Comparison with previous year depletions

    SciTech Connect

    Schoeberl, M.R.; Stolarski, R.S.; Krueger, A.J. )

    1989-05-01

    The 1988 spring Antarctic ozone depletion was observed by TOMS to be substantially smaller than in recent years. The minimum polar total ozone values declined only 15% during September 1988 compared to nearly 50% during September 1987. At southern midlatitudes, exceptionally high total ozone values were recorded beginning in July 1988. The total integrated southern hemispheric ozone increased rapidly during the Austral spring, approaching 1980 levels during October. The high midlatitude total ozone values were associated with a substantial increase in eddy activity as indicated by the standard deviation in total ozone in the zonal band 30{degree}-60{degree}S. The standard deviation also correlates with the QBO cycling of the tropical winds. Mechanisms through which the increased midlatitude eddy activity could disrupt the formation of the Antarctic ozone hole are briefly discussed.

  1. The 1988 Antarctic ozone depletion - Comparison with previous year depletions

    NASA Technical Reports Server (NTRS)

    Schoeberl, Mark R.; Stolarski, Richard S.; Krueger, Arlin J.

    1989-01-01

    The 1988 spring Antarctic ozone depletion was observed by TOMS to be substantially smaller than in recent years. The minimum polar total ozone values declined only 15 percent during September 1988, compared to nearly 50 percent during September 1987. At southern midlatitudes, exceptionally high total ozone values were recorded beginning in July 1988. The total integrated southern hemispheric ozone increased rapidly during the Austral spring, approaching 1980 levels during October. The high midlatitude total ozone values were associated with a substantial increase in eddy activity as indicated by the standard deviation in total ozone in the zonal band 30-60 deg S. Mechanisms through which the increased midlatitude eddy activity could disrupt the formation of the Antarctic ozone hole are briefly discussed.

  2. Depleted Argon from Underground Sources

    SciTech Connect

    Back, H. O.; Galbiati, C.; Goretti, A.; Loer, B.; Montanari, D.; Mosteiro, P.; Alexander, T.; Alton, A.; Rogers, H.; Kendziora, C.; Pordes, S.

    2011-04-27

    Argon is a strong scintillator and an ideal target for Dark Matter detection; however {sup 39}Ar contamination in atmospheric argon from cosmic ray interactions limits the size of liquid argon dark matter detectors due to pile-up. Argon from deep underground is depleted in {sup 39}Ar due to the cosmic ray shielding of the earth. In Cortez, Colorado, a CO{sub 2} well has been discovered to contain approximately 600 ppm of argon as a contamination in the CO{sub 2}. We first concentrate the argon locally to 3% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation, and then the N{sub 2} and He will be removed by continuous distillation to purify the argon. We have collected 26 kg of argon from the CO{sub 2} facility and a cryogenic distillation column is under construction at Fermilab to further purify the argon.

  3. Barium Depletion in Hollow Cathode Emitters

    NASA Technical Reports Server (NTRS)

    Polk, James E.; Capece, Angela M.; Mikellides, Ioannis G.; Katz, Ira

    2009-01-01

    The effect of tungsten erosion, transport and redeposition on the operation of dispenser hollow cathodes was investigated in detailed examinations of the discharge cathode inserts from an 8200 hour and a 30,352 hour ion engine wear test. Erosion and subsequent re-deposition of tungsten in the electron emission zone at the downstream end of the insert reduces the porosity of the tungsten matrix, preventing the ow of barium from the interior. This inhibits the interfacial reactions of the barium-calcium-aluminate impregnant with the tungsten in the pores. A numerical model of barium transport in the internal xenon discharge plasma shows that the barium required to reduce the work function in the emission zone can be supplied from upstream through the gas phase. Barium that flows out of the pores of the tungsten insert is rapidly ionized in the xenon discharge and pushed back to the emitter surface by the electric field and drag from the xenon ion flow. This barium ion flux is sufficient to maintain a barium surface coverage at the downstream end greater than 0.6, even if local barium production at that point is inhibited by tungsten deposits. The model also shows that the neutral barium pressure exceeds the equilibrium vapor pressure of the impregnant decomposition reaction over much of the insert length, so the reactions are suppressed. Only a small region upstream of the zone blocked by tungsten deposits is active and supplies the required barium. These results indicate that hollow cathode failure models based on barium depletion rates in vacuum dispenser cathodes are very conservative.

  4. CO depletion in the Gould Belt clouds

    NASA Astrophysics Data System (ADS)

    Christie, H.; Viti, S.; Yates, J.; Hatchell, J.; Fuller, G. A.; Duarte-Cabral, A.; Sadavoy, S.; Buckle, J. V.; Graves, S.; Roberts, J.; Nutter, D.; Davis, C.; White, G. J.; Hogerheijde, M.; Ward-Thompson, D.; Butner, H.; Richer, J.; Di Francesco, J.

    2012-05-01

    We present a statistical comparison of CO depletion in a set of local molecular clouds within the Gould Belt using Sub-millimetre Common User Bolometer Array (SCUBA) and Heterodyne Array Receiver Programme (HARP) data. This is the most wide-ranging study of depletion thus far within the Gould Belt. We estimate CO column densities assuming local thermodynamic equilibrium and, for a selection of sources, using the radiative transfer code RADEX in order to compare the two column density estimation methods. High levels of depletion are seen in the centres of several dust cores in all the clouds. We find that in the gas surrounding protostars, levels of depletion are somewhat lower than for starless cores with the exception of a few highly depleted protostellar cores in Serpens and NGC 2024. There is a tentative correlation between core mass and core depletion, particularly in Taurus and Serpens. Taurus has, on average, the highest levels of depletion. Ophiuchus has low average levels of depletion which could perhaps be related to the anomalous dust grain size distribution observed in this cloud. High levels of depletion are often seen around the edges of regions of optical emission (Orion) or in more evolved or less dynamic regions such as the bowl of L1495 in Taurus and the north-western region of Serpens.

  5. Growth hormone suppression test

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003376.htm Growth hormone suppression test To use the sharing features on this page, please enable JavaScript. The growth hormone suppression test determines whether growth hormone production is ...

  6. Dexamethasone suppression test

    MedlinePlus

    Dexamethasone suppression test measures whether adrenocorticotrophic hormone ( ACTH ) secretion by the pituitary can be suppressed. ... During this test, you will receive dexamethasone. This is a strong ... your blood is drawn so that the cortisol level in your blood ...

  7. Dexamethasone suppression test

    MedlinePlus

    DST; ACTH suppression test; Cortisol suppression test ... During this test, you will receive dexamethasone. This is a strong man-made (synthetic) glucocorticoid medication. Afterward, your blood is drawn ...

  8. Growth hormone suppression test

    MedlinePlus

    The growth hormone suppression test determines whether growth hormone production is being suppressed by high blood sugar. ... away. The lab measures the glucose and growth hormone (GH) levels in each sample.

  9. Depleted argon from underground sources

    SciTech Connect

    Back, H.O.; Alton, A.; Calaprice, F.; Galbiati, C.; Goretti, A.; Kendziora, C.; Loer, B.; Montanari, D.; Mosteiro, P.; Pordes, S.; /Fermilab

    2011-09-01

    Argon is a powerful scintillator and an excellent medium for detection of ionization. Its high discrimination power against minimum ionization tracks, in favor of selection of nuclear recoils, makes it an attractive medium for direct detection of WIMP dark matter. However, cosmogenic {sup 39}Ar contamination in atmospheric argon limits the size of liquid argon dark matter detectors due to pile-up. The cosmic ray shielding by the earth means that Argon from deep underground is depleted in {sup 39}Ar. In Cortez Colorado a CO{sub 2} well has been discovered to contain approximately 500ppm of argon as a contamination in the CO{sub 2}. In order to produce argon for dark matter detectors we first concentrate the argon locally to 3-5% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation. The N{sub 2} and He will be removed by continuous cryogenic distillation in the Cryogenic Distillation Column recently built at Fermilab. In this talk we will discuss the entire extraction and purification process; with emphasis on the recent commissioning and initial performance of the cryogenic distillation column purification.

  10. Beneficial Uses of Depleted Uranium

    SciTech Connect

    Brown, C.; Croff, A.G.; Haire, M. J.

    1997-08-01

    Naturally occurring uranium contains 0.71 wt% {sup 235}U. In order for the uranium to be useful in most fission reactors, it must be enriched the concentration of the fissile isotope {sup 235}U must be increased. Depleted uranium (DU) is a co-product of the processing of natural uranium to produce enriched uranium, and DU has a {sup 235}U concentration of less than 0.71 wt%. In the United States, essentially all of the DU inventory is in the chemical form of uranium hexafluoride (UF{sub 6}) and is stored in large cylinders above ground. If this co-product material were to be declared surplus, converted to a stable oxide form, and disposed, the costs are estimated to be several billion dollars. Only small amounts of DU have at this time been beneficially reused. The U.S. Department of Energy (DOE) has begun the Beneficial Uses of DU Project to identify large-scale uses of DU and encourage its reuse for the primary purpose of potentially reducing the cost and expediting the disposition of the DU inventory. This paper discusses the inventory of DU and its rate of increase; DU disposition options; beneficial use options; a preliminary cost analysis; and major technical, institutional, and regulatory issues to be resolved.

  11. Concentrations of Ozone-Depleting Substances

    EPA Science Inventory

    This indicator presents trends in global concentrations of ozone-depleting substances (ODSs) from 1992 to 2009. This trend is an important environmental issue, because ODSs can deplete the atmosphere's ability to shield the Earth from harmful ultraviolet rays.

  12. Tritium transport vessel using depleted uranium

    SciTech Connect

    Heung, L.K.

    1995-01-01

    A tritium transport vessel using depleted uranium was tested in the laboratory using deuterium and protium. The vessel contains 0.5 kg of depleted uranium and can hold up to 18 grams of tritium. The conditions for activation, tritium loading and tritium unloading were defined. The safety aspects that included air-ingress, tritium diffusion, temperature and pressure potentials were evaluated.

  13. Large-Scale Depletion of CD25+ Regulatory T Cells from Patient Leukapheresis Samples

    PubMed Central

    Powell, Daniel J.; Parker, Linda L.; Rosenberg, Steven A.

    2006-01-01

    Summary The ability to selectively enrich or deplete T lymphocytes of specific phenotype and function holds significant promise for application in adoptive immunotherapy protocols. Although CD4+ T cells can have an impact on CD8+ T-cell effector function, memory, and maintenance, a subset of CD4+ T cells, CD25+ regulatory T cells (Treg), can regulate peripheral self tolerance and possess the ability to suppress antitumor responses. The authors report the ability to selectively deplete CD25+ Treg cells from patient leukapheresis samples using a clinical-grade, large-scale immunomagnetic system. Using leukapheresis samples containing up to 1.3 × 1010 white blood cells, efficient depletion of Treg cells was measured by flow cytometric analysis of CD25 expression and FOXP3 expression on post-depletion products. Remnant CD25+ cells could not be detected in CD25-depleted products after short-term culture in IL-2 or enriched following secondary immunomagnetic selection for CD25+ cells, confirming that efficient depletion had occurred. In parallel to efficient enrichment of CD25− cells, immunomagnetic selection resulted in the recovery of Treg cells, since CD25+ lymphocytes removed during depletion were primarily composed of CD4+ T cells that expressed high levels of FOXP3 and possessed suppressive activity against autologous TCR-stimulated CD4+ CD25− T cells in vitro. These results show that selective separation of functional CD25+ Treg cells from large-scale samples can be performed in large scale under clinical-grade conditions with sufficient selection, recovery, viability, ability to expand, and function for potential use in adoptive immunotherapy. PMID:16000960

  14. Specification for the VERA Depletion Benchmark Suite

    SciTech Connect

    Kim, Kang Seog

    2015-12-17

    CASL-X-2015-1014-000 iii Consortium for Advanced Simulation of LWRs EXECUTIVE SUMMARY The CASL neutronics simulator MPACT is under development for the neutronics and T-H coupled simulation for the pressurized water reactor. MPACT includes the ORIGEN-API and internal depletion module to perform depletion calculations based upon neutron-material reaction and radioactive decay. It is a challenge to validate the depletion capability because of the insufficient measured data. One of the detoured methods to validate it is to perform a code-to-code comparison for benchmark problems. In this study a depletion benchmark suite has been developed and a detailed guideline has been provided to obtain meaningful computational outcomes which can be used in the validation of the MPACT depletion capability.

  15. High homocysteine induces betaine depletion

    PubMed Central

    Imbard, Apolline; Benoist, Jean-François; Esse, Ruben; Gupta, Sapna; Lebon, Sophie; de Vriese, An S; de Baulny, Helene Ogier; Kruger, Warren; Schiff, Manuel; Blom, Henk J.

    2015-01-01

    Betaine is the substrate of the liver- and kidney-specific betaine-homocysteine (Hcy) methyltransferase (BHMT), an alternate pathway for Hcy remethylation. We hypothesized that BHMT is a major pathway for homocysteine removal in cases of hyperhomocysteinaemia (HHcy). Therefore, we measured betaine in plasma and tissues from patients and animal models of HHcy of genetic and acquired cause. Plasma was collected from patients presenting HHcy without any Hcy interfering treatment. Plasma and tissues were collected from rat models of HHcy induced by diet and from a mouse model of cystathionine β-synthase (CBS) deficiency. S-adenosyl-methionine (AdoMet), S-adenosyl-homocysteine (AdoHcy), methionine, betaine and dimethylglycine (DMG) were quantified by ESI—LC–MS/MS. mRNA expression was quantified using quantitative real-time (QRT)-PCR. For all patients with diverse causes of HHcy, plasma betaine concentrations were below the normal values of our laboratory. In the diet-induced HHcy rat model, betaine was decreased in all tissues analysed (liver, brain, heart). In the mouse CBS deficiency model, betaine was decreased in plasma, liver, heart and brain, but was conserved in kidney. Surprisingly, BHMT expression and activity was decreased in liver. However, in kidney, BHMT and SLC6A12 expression was increased in CBS-deficient mice. Chronic HHcy, irrespective of its cause, induces betaine depletion in plasma and tissues (liver, brain and heart), indicating a global decrease in the body betaine pool. In kidney, betaine concentrations were not affected, possibly due to overexpression of the betaine transporter SLC6A12 where betaine may be conserved because of its crucial role as an osmolyte. PMID:26182429

  16. Iron Depletion Enhances Production of Antimicrobials by Pseudomonas aeruginosa

    PubMed Central

    Nguyen, Angela T.; Jones, Jace W.; Ruge, Max A.; Kane, Maureen A.

    2015-01-01

    ABSTRACT Cystic fibrosis (CF) is a heritable disease characterized by chronic, polymicrobial lung infections. While Staphylococcus aureus is the dominant lung pathogen in young CF patients, Pseudomonas aeruginosa becomes predominant by adulthood. P. aeruginosa produces a variety of antimicrobials that likely contribute to this shift in microbial populations. In particular, secretion of 2-alkyl-4(1H)-quinolones (AQs) contributes to lysis of S. aureus in coculture, providing an iron source to P. aeruginosa both in vitro and in vivo. We previously showed that production of one such AQ, the Pseudomonas quinolone signal (PQS), is enhanced by iron depletion and that this induction is dependent upon the iron-responsive PrrF small RNAs (sRNAs). Here, we demonstrate that antimicrobial activity against S. aureus during coculture is also enhanced by iron depletion, and we provide evidence that multiple AQs contribute to this activity. Strikingly, a P. aeruginosa ΔprrF mutant, which produces very little PQS in monoculture, was capable of mediating iron-regulated growth suppression of S. aureus. We show that the presence of S. aureus suppresses the ΔprrF1,2 mutant's defect in iron-regulated PQS production, indicating that a PrrF-independent iron regulatory pathway mediates AQ production in coculture. We further demonstrate that iron-regulated antimicrobial production is conserved in multiple P. aeruginosa strains, including clinical isolates from CF patients. These results demonstrate that iron plays a central role in modulating interactions of P. aeruginosa with S. aureus. Moreover, our studies suggest that established iron regulatory pathways of these pathogens are significantly altered during polymicrobial infections. IMPORTANCE Chronic polymicrobial infections involving Pseudomonas aeruginosa and Staphylococcus aureus are a significant cause of morbidity and mortality, as the interplay between these two organisms exacerbates infection. This is in part due to enhanced

  17. A parallel algorithm for implicit depletant simulations

    NASA Astrophysics Data System (ADS)

    Glaser, Jens; Karas, Andrew S.; Glotzer, Sharon C.

    2015-11-01

    We present an algorithm to simulate the many-body depletion interaction between anisotropic colloids in an implicit way, integrating out the degrees of freedom of the depletants, which we treat as an ideal gas. Because the depletant particles are statistically independent and the depletion interaction is short-ranged, depletants are randomly inserted in parallel into the excluded volume surrounding a single translated and/or rotated colloid. A configurational bias scheme is used to enhance the acceptance rate. The method is validated and benchmarked both on multi-core processors and graphics processing units for the case of hard spheres, hemispheres, and discoids. With depletants, we report novel cluster phases in which hemispheres first assemble into spheres, which then form ordered hcp/fcc lattices. The method is significantly faster than any method without cluster moves and that tracks depletants explicitly, for systems of colloid packing fraction ϕc < 0.50, and additionally enables simulation of the fluid-solid transition.

  18. Possible ozone depletions following nuclear explosions

    NASA Technical Reports Server (NTRS)

    Whitten, R. C.; Borucki, W. J.; Turco, R. P.

    1975-01-01

    The degree of depletion of the ozone layer ensuing after delivery of strategic nuclear warheads (5000 and 10,000 Mton) due to production of nitrogen oxides is theoretically assessed. Strong depletions are calculated for 16-km and 26-km altitudes, peaking 1-2 months after detonation and lasting for three years, while a significant depletion at 36 km would peak after one year. Assuming the explosions occur between 30 and 70 deg N, these effects should be much more pronounced in this region than over the Northern Hemisphere as a whole. It is concluded that Hampson's concern on this matter (1974) is well-founded.-

  19. Fire Suppression and Response

    NASA Technical Reports Server (NTRS)

    Ruff, Gary A.

    2004-01-01

    This report is concerned with the following topics regarding fire suppression:What is the relative effectiveness of candidate suppressants to extinguish a representative fire in reduced gravity, including high-O2 mole fraction, low -pressure environments? What are the relative advantages and disadvantages of physically acting and chemically-acting agents in spacecraft fire suppression? What are the O2 mole fraction and absolute pressure below which a fire cannot exist? What effect does gas-phase radiation play in the overall fire and post-fire environments? Are the candidate suppressants effective to extinguish fires on practical solid fuels? What is required to suppress non-flaming fires (smoldering and deep seated fires) in reduced gravity? How can idealized space experiment results be applied to a practical fire scenario? What is the optimal agent deployment strategy for space fire suppression?

  20. Prefoldin and Pins synergistically regulate asymmetric division and suppress dedifferentiation

    PubMed Central

    Zhang, Yingjie; Rai, Madhulika; Wang, Cheng; Gonzalez, Cayetano; Wang, Hongyan

    2016-01-01

    Prefoldin is a molecular chaperone complex that regulates tubulin function in mitosis. Here, we show that Prefoldin depletion results in disruption of neuroblast polarity, leading to neuroblast overgrowth in Drosophila larval brains. Interestingly, co-depletion of Prefoldin and Partner of Inscuteable (Pins) leads to the formation of gigantic brains with severe neuroblast overgrowth, despite that Pins depletion alone results in smaller brains with partially disrupted neuroblast polarity. We show that Prefoldin acts synergistically with Pins to regulate asymmetric division of both neuroblasts and Intermediate Neural Progenitors (INPs). Surprisingly, co-depletion of Prefoldin and Pins also induces dedifferentiation of INPs back into neuroblasts, while depletion either Prefoldin or Pins alone is insufficient to do so. Furthermore, knocking down either α-tubulin or β-tubulin in pins- mutant background results in INP dedifferentiation back into neuroblasts, leading to the formation of ectopic neuroblasts. Overexpression of α-tubulin suppresses neuroblast overgrowth observed in prefoldin pins double mutant brains. Our data elucidate an unexpected function of Prefoldin and Pins in synergistically suppressing dedifferentiation of INPs back into neural stem cells. PMID:27025979

  1. Coating Thermoelectric Devices To Suppress Sublimation

    NASA Technical Reports Server (NTRS)

    Sakamoto, Jeffrey; Caillat, Thierry; Fleurial, Jean-Pierre; Snyder, G. Jeffrey

    2007-01-01

    A technique for suppressing sublimation of key elements from skutterudite compounds in advanced thermoelectric devices has been demonstrated. The essence of the technique is to cover what would otherwise be the exposed skutterudite surface of such a device with a thin, continuous film of a chemically and physically compatible metal. Although similar to other sublimation-suppression techniques, this technique has been specifically tailored for application to skutterudite antimonides. The primary cause of deterioration of most thermoelectric materials is thermal decomposition or sublimation - one or more elements sublime from the hot side of a thermoelectric couple, changing the stoichiometry of the device. Examples of elements that sublime from their respective thermoelectric materials are Ge from SiGe, Te from Pb/Te, and now Sb from skutterudite antimonides. The skutterudite antimonides of primary interest are CoSb3 [electron-donor (n) type] and CeFe(3-x)Co(x)Sb12 [electron-acceptor (p) type]. When these compounds are subjected to typical operating conditions [temperature of 700 C and pressure <10(exp -5) torr (0.0013 Pa)], Sb sublimes from their surfaces, with the result that Sb depletion layers form and advance toward their interiors. As the depletion layer advances in a given device, the change in stoichiometry diminishes the thermal-to-electric conversion efficiency of the device. The problem, then, is to prevent sublimation, or at least reduce it to an acceptably low level. In preparation for an experiment on suppression of sublimation, a specimen of CoSb3 was tightly wrapped in a foil of niobium, which was selected for its chemical stability. In the experiment, the wrapped specimen was heated to a temperature of 700 C in a vacuum of residual pressure <10(exp -5) torr (0.0013 Pa), then cooled and sectioned. Examination of the sectioned specimen revealed that no depletion layer had formed, indicating the niobium foil prevented sublimation of antimony at 700 C

  2. Inhibition of lytic infection of pseudorabies virus by arginine depletion

    SciTech Connect

    Wang, H.-C.; Kao, Y.-C.; Chang, T-J.; Wong, M.-L. . E-mail: mlwong@dragon.nchu.edu.tw

    2005-08-26

    Pseudorabies virus (PRV) is a member of Alphahepesviruses; it is an enveloped virus with a double-stranded DNA genome. Polyamines (such as spermine and spermidine) are ubiquitous in animal cells and participate in cellular proliferation and differentiation. Previous results of our laboratory showed that the PRV can accomplish lytic infection either in the presence of exogenous spermine (or spermidine) or depletion of cellular polyamines. The amino acid arginine is a precursor of polyamine biosynthesis. In this work, we investigated the role of arginine in PRV infection. It was found that the plaque formation of PRV was inhibited by arginase (enzyme catalyzing the conversion of arginine into ornithine and urea) treatment whereas this inhibition can be reversed by exogenous arginine, suggesting that arginine is essential for PRV proliferation. Western blotting was conducted to study the effect of arginine depletion on the levels of structural proteins of PRV in virus-infected cells. Four PRV structural proteins (gB, gE, UL47, and UL48) were chosen for examination, and results revealed that the levels of viral proteins were obviously reduced in long time arginase treatment. However, the overall protein synthesis machinery was apparently not influenced by arginase treatment either in mock or PRV-infected cells. Analyzing with native gel, we found that arginase treatment affected the mobility of PRV structural proteins, suggesting the conformational change of viral proteins by arginine depletion. Heat shock proteins, acting as molecular chaperons, participate in protein folding and translocation. Our results demonstrated that long time arginase treatment could reduce the expression of cellular heat shock proteins 70 (hsc70 and hsp70), and transcriptional suppression of heat shock protein 70 gene promoter was one of the mechanisms involved in this reduced expression.

  3. Cystamine induces AIF-mediated apoptosis through glutathione depletion.

    PubMed

    Cho, Sung-Yup; Lee, Jin-Haeng; Ju, Mi-kyeong; Jeong, Eui Man; Kim, Hyo-Jun; Lim, Jisun; Lee, Seungun; Cho, Nam-Hyuk; Park, Hyun Ho; Choi, Kihang; Jeon, Ju-Hong; Kim, In-Gyu

    2015-03-01

    Cystamine and its reduced form cysteamine showed protective effects in various models of neurodegenerative disease, including Huntington's disease and Parkinson's disease. Other lines of evidence demonstrated the cytotoxic effect of cysteamine on duodenal mucosa leading to ulcer development. However, the mechanism for cystamine cytotoxicity remains poorly understood. Here, we report a new pathway in which cystamine induces apoptosis by targeting apoptosis-inducing factor (AIF). By screening of various cell lines, we observed that cystamine and cysteamine induce cell death in a cell type-specific manner. Comparison between cystamine-sensitive and cystamine-resistant cell lines revealed that cystamine cytotoxicity is not associated with unfolded protein response, reactive oxygen species generation and transglutaminase or caspase activity; rather, it is associated with the ability of cystamine to trigger AIF nuclear translocation. In cystamine-sensitive cells, cystamine suppresses the levels of intracellular glutathione by inhibiting γ-glutamylcysteine synthetase expression that triggers AIF translocation. Conversely, glutathione supplementation completely prevents cystamine-induced AIF translocation and apoptosis. In rats, cysteamine administration induces glutathione depletion and AIF translocation leading to apoptosis of duodenal epithelium. These results indicate that AIF translocation through glutathione depletion is the molecular mechanism of cystamine toxicity, and provide important implications for cystamine in the neurodegenerative disease therapeutics as well as in the regulation of AIF-mediated cell death. PMID:25549939

  4. Depleted uranium disposition study -- Supplement, Revision 1

    SciTech Connect

    Becker, G.W.

    1993-11-01

    The Department of Energy Office of Weapons and Materials Planning has requested a supplemental study to update the recent Depleted Uranium Disposition report. This supplemental study addresses new disposition alternatives and changes in status.

  5. A definition of depletion of fish stocks

    USGS Publications Warehouse

    Van Oosten, John

    1949-01-01

    Attention was focused on the need of a common and better understanding of the term depletion as applied to the fisheries in order to eliminate if possible the existing inexactness of thought on the subject. Depletion has been confused at various times with at least ten different ideas associated with it but which, as has has heen pointed out, are not synonymous at all. In defining depletion we must recognize that the term represents a condition and must not he confounded with the cause (overfishing) that leads to this condition or with the symptoms that identify it. Depletion was defined as a reduction, through overfishing, in the level of abundance of the exploitable segment of a stock that prevents the realization of the maximum productive capacity.

  6. Silicon Depletion in the Interstellar Medium

    NASA Astrophysics Data System (ADS)

    Haris, U.; Parvathi, V. S.; Gudennavar, S. B.; Bubbly, S. G.; Murthy, J.; Sofia, U. J.

    2016-06-01

    We report interstellar silicon (Si) depletion and dust-phase column densities of Si along 131 Galactic sight lines using archival observations. The data were corrected for differences in the assumed oscillator strength. This is a much larger sample than previous studies but confirms the majority of results, which state that the depletion of Si is correlated with the average density of hydrogen along the line of sight (< n({{H}})> ) as well as the fraction of hydrogen in molecular form (f(H2)). We also find that the linear part of the extinction curve is independent of Si depletion. Si depletion is correlated with the bump strength (c3/RV) and the FUV curvature (c4/RV) suggesting that silicon plays a significant role in both the 2175 Å bump and the FUV rise.

  7. Exhaustible Resource Depletion: A Modified Graphical Approach.

    ERIC Educational Resources Information Center

    Tisato, Peter

    1995-01-01

    Presents a graphical analysis of the exhaustible resource depletion problem. Applies Hotelling's "r percent rule" as a new approach that operates in an "N"-period context. Includes two figures illustrating the approach. (CFR)

  8. Polar stratospheric clouds and ozone depletion

    NASA Technical Reports Server (NTRS)

    Toon, Owen B.; Turco, Richard P.

    1991-01-01

    A review is presented of investigations into the correlation between the depletion of ozone and the formation of polar stratospheric clouds (PSCs). Satellite measurements from Nimbus 7 showed that over the years the depletion from austral spring to austral spring has generally worsened. Approximately 70 percent of the ozone above Antarctica, which equals about 3 percent of the earth's ozone, is lost during September and October. Various hypotheses for ozone depletion are discussed including the theory suggesting that chlorine compounds might be responsible for the ozone hole, whereby chlorine enters the atmosphere as a component of chlorofluorocarbons produced by humans. The three types of PSCs, nitric acid trihydrate, slowly cooling water-ice, and rapidly cooling water-ice clouds act as important components of the Antarctic ozone depletion. It is indicated that destruction of the ozone will be more severe each year for the next few decades, leading to a doubling in area of the Antarctic ozone hole.

  9. An assessment of alternatives and technologies for replacing ozone- depleting substances at DOE facilities

    SciTech Connect

    Purcell, C.W.; Miller, K.B.; Friedman, J.R.; Rapoport, R.D.; Conover, D.R.; Hendrickson, P.L. ); Koss, T.C. . Office of Environmental Guidance)

    1992-10-01

    Title VI of the Clean Air Act, as amended, mandates a production phase-out for ozone-depleting substances (ODSs). These requirements will have a significant impact on US Department of Energy (DOE) facilities. Currently, DOE uses ODSs in three major activities: fire suppression (halon), refrigeration and cooling (chlorofluorocarbons [CFCs]), and cleaning that requires solvents (CFCs, methyl chloroform, and carbon tetrachloride). This report provides basic information on methods and strategies to phase out use of ODSs at DOE facilities.

  10. Depleted uranium: A DOE management guide

    SciTech Connect

    1995-10-01

    The U.S. Department of Energy (DOE) has a management challenge and financial liability in the form of 50,000 cylinders containing 555,000 metric tons of depleted uranium hexafluoride (UF{sub 6}) that are stored at the gaseous diffusion plants. The annual storage and maintenance cost is approximately $10 million. This report summarizes several studies undertaken by the DOE Office of Technology Development (OTD) to evaluate options for long-term depleted uranium management. Based on studies conducted to date, the most likely use of the depleted uranium is for shielding of spent nuclear fuel (SNF) or vitrified high-level waste (HLW) containers. The alternative to finding a use for the depleted uranium is disposal as a radioactive waste. Estimated disposal costs, utilizing existing technologies, range between $3.8 and $11.3 billion, depending on factors such as applicability of the Resource Conservation and Recovery Act (RCRA) and the location of the disposal site. The cost of recycling the depleted uranium in a concrete based shielding in SNF/HLW containers, although substantial, is comparable to or less than the cost of disposal. Consequently, the case can be made that if DOE invests in developing depleted uranium shielded containers instead of disposal, a long-term solution to the UF{sub 6} problem is attained at comparable or lower cost than disposal as a waste. Two concepts for depleted uranium storage casks were considered in these studies. The first is based on standard fabrication concepts previously developed for depleted uranium metal. The second converts the UF{sub 6} to an oxide aggregate that is used in concrete to make dry storage casks.

  11. A new definition of maternal depletion syndrome.

    PubMed Central

    Winkvist, A; Rasmussen, K M; Habicht, J P

    1992-01-01

    BACKGROUND. Although the term "maternal depletion syndrome" has been commonly used to explain poor maternal and infant health, whether such a syndrome actually exists remains unclear. This uncertainty may be due to the lack of a clear definition of the syndrome and the absence of theoretical frameworks that account for the many factors related to reproductive nutrition. METHODS. We propose a new definition of maternal depletion syndrome within a framework that accounts for potential confounding factors. RESULTS. Our conceptual framework distinguishes between childbearing pattern and inadequate diet as causes of poor maternal health; hence, our definition of maternal depletion syndrome has both biological and practical meaning. The new definition is based on overall change in maternal nutritional status over one reproductive cycle in relation to possible depletion and repletion phases and in relation to initial nutritional status. CONCLUSIONS. The empirical application of this approach should permit the testing of the existence of maternal depletion syndrome in the developing world, and the distinction between populations where family planning will alleviate maternal depletion and those in which an improved diet is also necessary. PMID:1566948

  12. Neutrophil depletion after subarachnoid hemorrhage improves memory via NMDA receptors.

    PubMed

    Provencio, Jose Javier; Swank, Valerie; Lu, Haiyan; Brunet, Sylvain; Baltan, Selva; Khapre, Rohini V; Seerapu, Himabindu; Kokiko-Cochran, Olga N; Lamb, Bruce T; Ransohoff, Richard M

    2016-05-01

    Cognitive deficits after aneurysmal subarachnoid hemorrhage (SAH) are common and disabling. Patients who experience delayed deterioration associated with vasospasm are likely to have cognitive deficits, particularly problems with executive function, verbal and spatial memory. Here, we report neurophysiological and pathological mechanisms underlying behavioral deficits in a murine model of SAH. On tests of spatial memory, animals with SAH performed worse than sham animals in the first week and one month after SAH suggesting a prolonged injury. Between three and six days after experimental hemorrhage, mice demonstrated loss of late long-term potentiation (L-LTP) due to dysfunction of the NMDA receptor. Suppression of innate immune cell activation prevents delayed vasospasm after murine SAH. We therefore explored the role of neutrophil-mediated innate inflammation on memory deficits after SAH. Depletion of neutrophils three days after SAH mitigates tissue inflammation, reverses cerebral vasoconstriction in the middle cerebral artery, and rescues L-LTP dysfunction at day 6. Spatial memory deficits in both the short and long-term are improved and associated with a shift of NMDA receptor subunit composition toward a memory sparing phenotype. This work supports further investigating suppression of innate immunity after SAH as a target for preventative therapies in SAH. PMID:26872422

  13. The New MCNP6 Depletion Capability

    SciTech Connect

    Fensin, Michael Lorne; James, Michael R.; Hendricks, John S.; Goorley, John T.

    2012-06-19

    The first MCNP based inline Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. Both the MCNP5 and MCNPX codes have historically provided a successful combinatorial geometry based, continuous energy, Monte Carlo radiation transport solution for advanced reactor modeling and simulation. However, due to separate development pathways, useful simulation capabilities were dispersed between both codes and not unified in a single technology. MCNP6, the next evolution in the MCNP suite of codes, now combines the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. We describe here the new capabilities of the MCNP6 depletion code dating from the official RSICC release MCNPX 2.6.0, reported previously, to the now current state of MCNP6. NEA/OECD benchmark results are also reported. The MCNP6 depletion capability enhancements beyond MCNPX 2.6.0 reported here include: (1) new performance enhancing parallel architecture that implements both shared and distributed memory constructs; (2) enhanced memory management that maximizes calculation fidelity; and (3) improved burnup physics for better nuclide prediction. MCNP6 depletion enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. The enhancements described here help provide a powerful capability as well as dictate a path forward for future development to improve the usefulness of the technology.

  14. Depletion sensitivity predicts unhealthy snack purchases.

    PubMed

    Salmon, Stefanie J; Adriaanse, Marieke A; Fennis, Bob M; De Vet, Emely; De Ridder, Denise T D

    2016-01-01

    The aim of the present research is to examine the relation between depletion sensitivity - a novel construct referring to the speed or ease by which one's self-control resources are drained - and snack purchase behavior. In addition, interactions between depletion sensitivity and the goal to lose weight on snack purchase behavior were explored. Participants included in the study were instructed to report every snack they bought over the course of one week. The dependent variables were the number of healthy and unhealthy snacks purchased. The results of the present study demonstrate that depletion sensitivity predicts the amount of unhealthy (but not healthy) snacks bought. The more sensitive people are to depletion, the more unhealthy snacks they buy. Moreover, there was some tentative evidence that this relation is more pronounced for people with a weak as opposed to a strong goal to lose weight, suggesting that a strong goal to lose weight may function as a motivational buffer against self-control failures. All in all, these findings provide evidence for the external validity of depletion sensitivity and the relevance of this construct in the domain of eating behavior. PMID:26321417

  15. The new MCNP6 depletion capability

    SciTech Connect

    Fensin, M. L.; James, M. R.; Hendricks, J. S.; Goorley, J. T.

    2012-07-01

    The first MCNP based in-line Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. Both the MCNP5 and MCNPX codes have historically provided a successful combinatorial geometry based, continuous energy, Monte Carlo radiation transport solution for advanced reactor modeling and simulation. However, due to separate development pathways, useful simulation capabilities were dispersed between both codes and not unified in a single technology. MCNP6, the next evolution in the MCNP suite of codes, now combines the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. We describe here the new capabilities of the MCNP6 depletion code dating from the official RSICC release MCNPX 2.6.0, reported previously, to the now current state of MCNP6. NEA/OECD benchmark results are also reported. The MCNP6 depletion capability enhancements beyond MCNPX 2.6.0 reported here include: (1) new performance enhancing parallel architecture that implements both shared and distributed memory constructs; (2) enhanced memory management that maximizes calculation fidelity; and (3) improved burnup physics for better nuclide prediction. MCNP6 depletion enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. The enhancements described here help provide a powerful capability as well as dictate a path forward for future development to improve the usefulness of the technology. (authors)

  16. Synergistic effects of combined DNA methyltransferase inhibition and MBD2 depletion on breast cancer cells; MBD2 depletion blocks 5-aza-2ʹ-deoxycytidine-triggered invasiveness

    PubMed Central

    Cheishvili, David; Chik, Flora; Li, Chen Chen; Bhattacharya, Bishnu; Suderman, Matthew; Arakelian, Ani; Hallett, Michael; Rabbani, Shafaat A.; Szyf, Moshe

    2014-01-01

    5-Aza-2ʹ-deoxycytidine (5-azaCdR) not only inhibits growth of non-invasive breast cancer cells but also increases their invasiveness through induction of pro-metastatic genes. Methylated DNA binding protein 2 (MBD2) is involved in silencing methylated tumor suppressor genes as well as activation of pro-metastatic genes. In this study, we show that a combination of MBD2 depletion and DNA methyltransferases (DNMT) inhibition in breast cancer cells results in a combined effect in vitro and in vivo, enhancing tumor growth arrest on one hand, while inhibiting invasiveness triggered by 5-azaCdR on the other hand. The combined treatment of MBD2 depletion and 5-azaCdR suppresses and augments distinct gene networks that are induced by DNMT inhibition alone. These data point to a potential new approach in targeting the DNA methylation machinery by combination of MBD2 and DNMT inhibitors. PMID:25178277

  17. The modality effect of ego depletion: Auditory task modality reduces ego depletion.

    PubMed

    Li, Qiong; Wang, Zhenhong

    2016-08-01

    An initial act of self-control that impairs subsequent acts of self-control is called ego depletion. The ego depletion phenomenon has been observed consistently. The modality effect refers to the effect of the presentation modality on the processing of stimuli. The modality effect was also robustly found in a large body of research. However, no study to date has examined the modality effects of ego depletion. This issue was addressed in the current study. In Experiment 1, after all participants completed a handgrip task, one group's participants completed a visual attention regulation task and the other group's participants completed an auditory attention regulation task, and then all participants again completed a handgrip task. The ego depletion phenomenon was observed in both the visual and the auditory attention regulation task. Moreover, participants who completed the visual task performed worse on the handgrip task than participants who completed the auditory task, which indicated that there was high ego depletion in the visual task condition. In Experiment 2, participants completed an initial task that either did or did not deplete self-control resources, and then they completed a second visual or auditory attention control task. The results indicated that depleted participants performed better on the auditory attention control task than the visual attention control task. These findings suggest that altering task modality may reduce ego depletion. PMID:27241617

  18. Neutral depletion and the helicon density limit

    SciTech Connect

    Magee, R. M.; Galante, M. E.; Carr, J. Jr.; Lusk, G.; McCarren, D. W.; Scime, E. E.

    2013-12-15

    It is straightforward to create fully ionized plasmas with modest rf power in a helicon. It is difficult, however, to create plasmas with density >10{sup 20} m{sup −3}, because neutral depletion leads to a lack of fuel. In order to address this density limit, we present fast (1 MHz), time-resolved measurements of the neutral density at and downstream from the rf antenna in krypton helicon plasmas. At the start of the discharge, the neutral density underneath the antenna is reduced to 1% of its initial value in 15 μs. The ionization rate inferred from these data implies that the electron temperature near the antenna is much higher than the electron temperature measured downstream. Neutral density measurements made downstream from the antenna show much slower depletion, requiring 14 ms to decrease by a factor of 1/e. Furthermore, the downstream depletion appears to be due to neutral pumping rather than ionization.

  19. Global Warming: Lessons from Ozone Depletion

    NASA Astrophysics Data System (ADS)

    Hobson, Art

    2010-11-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of Arkansas have developed a conceptual understanding of energy and of electromagnetism, including the electromagnetic spectrum, I devote a lecture (and a textbook section) to ozone depletion and another lecture (and section) to global warming. Humankind came together in 1986 and quickly solved, to the extent that humans can solve it, ozone depletion. We could do the same with global warming, but we haven't and as yet there's no sign that we will. The parallel between the ozone and global warming cases, and the difference in outcomes, are striking and instructive.

  20. Ozone depletion and chlorine loading potentials

    NASA Technical Reports Server (NTRS)

    Pyle, John A.; Wuebbles, Donald J.; Solomon, Susan; Zvenigorodsky, Sergei; Connell, Peter; Ko, Malcolm K. W.; Fisher, Donald A.; Stordal, Frode; Weisenstein, Debra

    1991-01-01

    The recognition of the roles of chlorine and bromine compounds in ozone depletion has led to the regulation or their source gases. Some source gases are expected to be more damaging to the ozone layer than others, so that scientific guidance regarding their relative impacts is needed for regulatory purposes. Parameters used for this purpose include the steady-state and time-dependent chlorine loading potential (CLP) and the ozone depletion potential (ODP). Chlorine loading potentials depend upon the estimated value and accuracy of atmospheric lifetimes and are subject to significant (approximately 20-50 percent) uncertainties for many gases. Ozone depletion potentials depend on the same factors, as well as the evaluation of the release of reactive chlorine and bromine from each source gas and corresponding ozone destruction within the stratosphere.

  1. Cough suppression disorders spectrum.

    PubMed

    Reich, Jerome M

    2014-02-01

    Volitional cough suppression, identified exclusively in females, is an unusual causal mechanism for instances of lobar atalectasis and bronchiectasis. It is a postulated mechanism for the genesis of Lady Windermere Syndrome. PMID:24462261

  2. Jet Noise Suppression

    NASA Technical Reports Server (NTRS)

    Gliebe, P. R.; Brausch, J. F.; Majjigi, R. K.; Lee, R.

    1991-01-01

    The objectives of this chapter are to review and summarize the jet noise suppression technology, to provide a physical and theoretical model to explain the measured jet noise suppression characteristics of different concepts, and to provide a set of guidelines for evolving jet noise suppression designs. The underlying principle for all jet noise suppression devices is to enhance rapid mixing (i.e., diffusion) of the jet plume by geometric and aerothermodynamic means. In the case of supersonic jets, the shock-cell broadband noise reduction is effectively accomplished by the elimination or mitigation of the shock-cell structure. So far, the diffusion concepts have predominantly concentrated on jet momentum and energy (kinetic and thermal) diffusion, in that order, and have yielded better noise reduction than the simple conical nozzles. A critical technology issue that needs resolution is the effect of flight on the noise suppression potential of mechanical suppressor nozzles. A more thorough investigation of this mechanism is necessary for the successful development and design of an acceptable noise suppression device for future high-speed civil transports.

  3. Role of Central Serotonin in Anticipation of Rewarding and Punishing Outcomes: Effects of Selective Amygdala or Orbitofrontal 5-HT Depletion.

    PubMed

    Rygula, Rafal; Clarke, Hannah F; Cardinal, Rudolf N; Cockcroft, Gemma J; Xia, Jing; Dalley, Jeff W; Robbins, Trevor W; Roberts, Angela C

    2015-09-01

    Understanding the role of serotonin (or 5-hydroxytryptamine, 5-HT) in aversive processing has been hampered by the contradictory findings, across studies, of increased sensitivity to punishment in terms of subsequent response choice but decreased sensitivity to punishment-induced response suppression following gross depletion of central 5-HT. To address this apparent discrepancy, the present study determined whether both effects could be found in the same animals by performing localized 5-HT depletions in the amygdala or orbitofrontal cortex (OFC) of a New World monkey, the common marmoset. 5-HT depletion in the amygdala impaired response choice on a probabilistic visual discrimination task by increasing the effectiveness of misleading, or false, punishment and reward, and decreased response suppression in a variable interval test of punishment sensitivity that employed the same reward and punisher. 5-HT depletion in the OFC also disrupted probabilistic discrimination learning and decreased response suppression. Computational modeling of behavior on the discrimination task showed that the lesions reduced reinforcement sensitivity. A novel, unitary account of the findings in terms of the causal role of 5-HT in the anticipation of both negative and positive motivational outcomes is proposed and discussed in relation to current theories of 5-HT function and our understanding of mood and anxiety disorders. PMID:24879752

  4. “When the going gets tough, who keeps going?” Depletion sensitivity moderates the ego-depletion effect

    PubMed Central

    Salmon, Stefanie J.; Adriaanse, Marieke A.; De Vet, Emely; Fennis, Bob M.; De Ridder, Denise T. D.

    2014-01-01

    Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In three studies, we assessed individual differences in depletion sensitivity, and demonstrate that depletion sensitivity moderates ego-depletion effects. The Depletion Sensitivity Scale (DSS) was employed to assess depletion sensitivity. Study 1 employs the DSS to demonstrate that individual differences in sensitivity to ego-depletion exist. Study 2 shows moderate correlations of depletion sensitivity with related self-control concepts, indicating that these scales measure conceptually distinct constructs. Study 3 demonstrates that depletion sensitivity moderates the ego-depletion effect. Specifically, participants who are sensitive to depletion performed worse on a second self-control task, indicating a stronger ego-depletion effect, compared to participants less sensitive to depletion. PMID:25009523

  5. Direct Visualization of an Impurity Depletion Zone

    NASA Technical Reports Server (NTRS)

    Chernov, Alex A.; Garcia-Ruiz, Juan Ma; Thomas, Bill R.

    2000-01-01

    When a crystal incorporates more impurity per unit of its volume than the impurity concentration in solution, the solution in vicinity of the growing crystal is depleted with respect to the impurity I,2. With a stagnant solution, e. g. in microgravity or gels, an impurity depletion zone expands as the crystal grows and results in greater purity in most of the outer portion of the crystal than in the core. Crystallization in gel provides an opportunity to mimic microgravity conditions and visualize the impurity depletion zone. Colorless, transparent apoferritin (M congruent to 450 KDa) crystals were grown in the presence of red holoferritin dimer as a microheterogeneous impurity (M congruent to 900 KDa) within agarose gel by counterdiffusion with Cd(2+) precipitant. Preferential trapping of dimers, (distribution coefficient K = 4 (exp 1,2)) results in weaker red color around the crystals grown in the left tube in the figure as compared to the control middle tube without crystals. The left and the middle tubes contain colored ferritin dimers, the right tube contains colored trimers. The meniscus in the left tube separate gel (below) and liquid solution containing Cd(2+) (above). Similar solutions, though without precipitants, were present on top of the middle and right tube allowing diffusion of dimers and trimers. The area of weaker color intensity around crystals directly demonstrates overlapped impurity depletion zones.

  6. ATMOSPHERIC BENZENE DEPLETION BY SOIL MICROORGANISMS

    EPA Science Inventory

    Gaseous benzene was rapidly depleted in exposure chambers containing viable soils and plants. When separate components of the system were analyzed, no benzene was detected in soils, plants, or water. Soil microorganisms were shown to be responsible for metabolizing benzene, yield...

  7. Demonstration of jackhammer incorporating depleted uranium

    SciTech Connect

    Fischer, L E; Hoard, R W; Carter, D L; Saculla, M D; Wilson, G V

    2000-04-01

    The United States Government currently has an abundance of depleted uranium (DU). This surplus of about 1 billion pounds is the result of an enrichment process using gaseous diffusion to produce enriched and depleted uranium. The enriched uranium has been used primarily for either nuclear weapons for the military or nuclear fuel for the commercial power industry. Most of the depleted uranium remains at the enrichment process plants in the form of depleted uranium hexafluoride (DUF{sub 6}). The Department of Energy (DOE) recently began a study to identify possible commercial applications for the surplus material. One of these potential applications is to use the DU in high-density strikers/hammers in pneumatically driven tools, such as jack hammers and piledrivers to improve their impulse performance. The use of DU could potentially increase tunneling velocity and excavation into target materials with improved efficiency. This report describes the efforts undertaken to analyze the particulars of using DU in two specific striking applications: the jackhammer and chipper tool.

  8. NON-OZONE DEPLETING MOBILE HEAT PUMP

    EPA Science Inventory

    To address the growing environmental and logistical burden posed by continued use of Class I ozone depleting chemicals (ODCs), this co-funded Environmental Security Technology Certification Program (ESTCP) and United States Air Force (USAF) Science and Technology project sought t...

  9. Platelet depletion and severity of streptococcal endocarditis

    PubMed Central

    Dall, Lawrence; Miller, Todd; Herndon, Betty; Diez, Ireneo; Dew, Michelle

    1998-01-01

    OBJECTIVE: To evaluate the importance of thrombocytopenia in streptococcal endocarditis using an animal model. DESIGN: A model of human septic endocarditis was established in rats (polyethylene catheters across the aortic valve and administration of Streptococcus sanguis, 5×107 colony forming units [cfu] intravenous). Thrombocytopenia at four levels was produced by antiplatelet serum. Secondary methods of producing thrombocytopenia were also evaluated. At sacrifice (96 h after platelet depletion and 72 h after infection), vegetations were removed, weighed, diluted, plated and counted. Potential mechanisms of the dose-response relationship between vegetation density and platelet count were evaluated. SETTING: Controlled research laboratory experiments. POPULATION STUDIED: Animal models of streptococcal endocarditis. MAIN RESULTS: The bacterial density of the aortic valve vegetations significantly increased as the platelet count decreased (P=0.0007). In severely thrombocytopenic animals (two-dose antiplatelet serum), data suggest increased vegetation embolism. Platelet depletion, which was minimal with chemical methods, was produced most effectively by antithrombocyte serum. Platelet surfaces in endocarditis were found to express elevated CD62p proteins (72.7% endocarditis, 34.7% control). Platelet protein fractions were evaluated in vitro by both streptocidal (P=0.19) and phagocytosis-stimulating assays. Platelet presence in mature aortic valve vegetations averaged only about 2%. CONCLUSIONS: In platelet depletion experiments using a rat model, a dose-response relationship of peripheral circulating platelet depletion to aortic valve vegetation density was found. The mechanism relating thrombocytopenia to endocarditis severity remains unresolved. PMID:22346555

  10. Global Warming: Lessons from Ozone Depletion

    ERIC Educational Resources Information Center

    Hobson, Art

    2010-01-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of…

  11. Dissolution Treatment of Depleted Uranium Waste

    SciTech Connect

    Gates-Anderson, D D; Laue, C A; Fitch, T E

    2004-02-09

    Researchers at LLNL have developed a 3-stage process that converts pyrophoric depleted uranium metal turnings to a solidified final product that can be transported to and buried at a permitted land disposal site. The three process stages are: (1) pretreatment; (2) dissolution; and (3) solidification. Each stage was developed following extensive experimentation. This report presents the results of their experimental studies.

  12. Retinal Pigment Epithelial Cell Line Suppression of Phagolysosome Activation

    PubMed Central

    Taylor, AW; Dixit, S; Yu, J

    2015-01-01

    The eye is an immune privileged tissue with multiple mechanisms of immunosuppression to protect the light gathering tissues from the damage of inflammation. One of theses mechanisms involves retinal pigment epithelial cell suppression of phagosome activation in macrophages. The objective of this work is to determine if the human RPE cell line ARPE-19 is capable of suppressing the activation of the phagolysosome in macrophages in a manner similar to primary RPE. The conditioned media of RPE eyecups, sub-confluent, just confluent cultures, or established confluent cultures of human ARPE-19 cells were generated. These condition media were used to treat macrophages phagocytizing pHrodo bioparticles. After 24 hours incubation the macrophages were imaged by fluorescent microscopy, and fluorescence was measured. The fluorescent intensity is proportional to the amount of bioparticles phagocytized and are in an activated phagolysosome. The conditioned media of in situ mouse RPE eyecups significantly suppressed the activation of phagolysosome. The conditioned media from cultures of human ARPE-19 cells, grown to sub-confluence (50%) or grown to confluence had no effect on phagolysosome activation. In contrast, the conditioned media from established confluent cultures significantly suppressed phagolysosome activation. The neuropeptides alpha-MSH and NPY were depleted from the conditioned media of established confluent ARPE-19 cell cultures. This depleted conditioned media had diminished suppression of phagolysosome activation while promoting macrophage cell death. In addition, the condition media from cultures of ARPE-19 monolayers wounded with a bisecting scrape was diminished in suppressing phagolysosome activation. This technical report suggests that like primary RPE monolayers, established confluent cultures of ARPE-19 cells produce soluble factors that suppress the activation of macrophages, and can be used to study the molecular mechanisms of retinal immunobiology. In

  13. Diphtheria toxin-based recombinant murine IL-2 fusion toxin for depleting murine regulatory T cells in vivo.

    PubMed

    Wei, Min; Marino, Jose; Trowell, Aaron; Zhang, Huiping; Stromp Peraino, Jaclyn; Rajasekera, Priyani V; Madsen, Joren C; Sachs, David H; Huang, Christene A; Benichou, Gilles; Wang, Zhirui

    2014-09-01

    Regulatory T cells (Tregs) are a subpopulation of CD4(+) T cells which suppress immune responses of effector cells and are known to play a very important role in protection against autoimmune disease development, induction of transplantation tolerance and suppression of effective immune response against tumor cells. An effective in vivo Treg depletion agent would facilitate Treg-associated studies across many research areas. In this study, we have developed diphtheria toxin-based monovalent and bivalent murine IL-2 fusion toxins for depleting murine IL-2 receptor positive cells including CD25(+) Treg in vivo. Their potencies were assessed by in vitro protein synthesis inhibition and cell proliferation inhibition assays using a murine CD25(+) CTLL-2 cell line. Surprisingly, in contrast to our previously developed recombinant fusion toxins, the monovalent isoform (DT390-mIL-2) was approximately 4-fold more potent than its bivalent counterpart (DT390-bi-mIL-2). Binding analysis by flow cytometry demonstrated that the monovalent isoform bound stronger than the bivalent version. In vivo Treg depletion with the monovalent murine IL-2 fusion toxin was performed using C57BL/6J (B6) mice. Spleen Treg were significantly depleted with a maximum reduction of ∼70% and detectable as early as 12 h after the last injection. The spleen Treg numbers were reduced until Day 3 and returned to control levels by Day 7. We believe that this monovalent murine IL-2 fusion toxin will be an effective in vivo murine Treg depleter. PMID:25147093

  14. Tumor cell migration and invasion are enhanced by depletion of Rap1 GTPase-activating protein (Rap1GAP).

    PubMed

    Tsygankova, Oxana M; Wang, Hongbin; Meinkoth, Judy L

    2013-08-23

    The functional significance of the widespread down-regulation of Rap1 GTPase-activating protein (Rap1GAP), a negative regulator of Rap activity, in human tumors is unknown. Here we show that human colon cancer cells depleted of Rap1GAP are endowed with more aggressive migratory and invasive properties. Silencing Rap1GAP enhanced the migration of confluent and single cells. In the latter, migration distance, velocity, and directionality were increased. Enhanced migration was a consequence of increased endogenous Rap activity as silencing Rap expression selectively abolished the migration of Rap1GAP-depleted cells. ROCK-mediated cell contractility was suppressed in Rap1GAP-depleted cells, which exhibited a spindle-shaped morphology and abundant membrane protrusions. Tumor cells can switch between Rho/ROCK-mediated contractility-based migration and Rac1-mediated mesenchymal motility. Strikingly, the migration of Rap1GAP-depleted, but not control cells required Rac1 activity, suggesting that loss of Rap1GAP alters migratory mechanisms. Inhibition of Rac1 activity restored membrane blebbing and increased ROCK activity in Rap1GAP-depleted cells, suggesting that Rac1 contributes to the suppression of contractility. Collectively, these findings identify Rap1GAP as a critical regulator of aggressive tumor cell behavior and suggest that the level of Rap1GAP expression influences the migratory mechanisms that are operative in tumor cells. PMID:23864657

  15. Suppression of Parathyroid Hormone in a Patient with Severe Magnesium Depletion

    PubMed Central

    Fernandez, Isaac; Kochar, Tina

    2016-01-01

    Hypomagnesemia is often associated with coexisting electrolyte abnormalities like hypokalemia and hypocalcemia. Hypocalcemia has been shown to be secondary to hypoparathyroidism induced by hypomagnesemia. Here, we discuss a case of a patient with severe hypomagnesemia and associated hypocalcemia. A 38-year-old lady was admitted to the hospital for weakness of lower extremities and an eventual fall. The exam was significant for decreased motor strength and some paresthesias. The laboratory data was significant for hypomagnesemia, hypokalemia, and low parathyroid level in the face of hypocalcemia. After replacing magnesium, the parathyroid hormone levels normalized and led to eventual correction of calcium levels without any additional calcium replacement therapy. There was complete symptom resolution with correction of electrolyte abnormalities. This case highlights the importance of looking for all associated abnormalities in a patient with hypomagnesemia and starting the replacement therapy by first replacing the magnesium and then the others as needed. Replacing the magnesium alone may correct the hypoparathyroidism and eliminate the need for calcium replacement. PMID:27190662

  16. Polyamine depletion inhibits the autophagic response modulating Trypanosoma cruzi infectivity

    PubMed Central

    Vanrell, María C.; Cueto, Juan A.; Barclay, Jeremías J.; Carrillo, Carolina; Colombo, María I.; Gottlieb, Roberta A.; Romano, Patricia S.

    2013-01-01

    Autophagy is a cell process that in normal conditions serves to recycle cytoplasmic components and aged or damaged organelles. The autophagic pathway has been implicated in many physiological and pathological situations, even during the course of infection by intracellular pathogens. Many compounds are currently used to positively or negatively modulate the autophagic response. Recently it was demonstrated that the polyamine spermidine is a physiological inducer of autophagy in eukaryotic cells. We have previously shown that the etiological agent of Chagas disease, the protozoan parasite Trypanosoma cruzi, interacts with autophagic compartments during host cell invasion and that preactivation of autophagy significantly increases host cell colonization by this parasite. In the present report we have analyzed the effect of polyamine depletion on the autophagic response of the host cell and on T. cruzi infectivity. Our data showed that depleting intracellular polyamines by inhibiting the biosynthetic enzyme ornithine decarboxylase with difluoromethylornithine (DFMO) suppressed the induction of autophagy in response to starvation or rapamycin treatment in two cell lines. This effect was associated with a decrease in the levels of LC3 and ATG5, two proteins required for autophagosome formation. As a consequence of inhibiting host cell autophagy, DFMO impaired T. cruzi colonization, indicating that polyamines and autophagy facilitate parasite infection. Thus, our results point to DFMO as a novel autophagy inhibitor. While other autophagy inhibitors such as wortmannin and 3-methyladenine are nonspecific and potentially toxic, DFMO is an FDA-approved drug that may have value in limiting autophagy and the spread of the infection in Chagas disease and possibly other pathological settings. PMID:23697944

  17. How Depleted is the MORB mantle?

    NASA Astrophysics Data System (ADS)

    Hofmann, A. W.; Hart, S. R.

    2015-12-01

    Knowledge of the degree of mantle depletion of highly incompatible elements is critically important for assessing Earth's internal heat production and Urey number. Current views of the degree of MORB source depletion are dominated by Salters and Stracke (2004), and Workman and Hart (2005). The first is based on an assessment of average MORB compositions, whereas the second considers trace element data of oceanic peridotites. Both require an independent determination of one absolute concentration, Lu (Salters & Stracke), or Nd (Workman & Hart). Both use parent-daughter ratios Lu/Hf, Sm/Nd, and Rb/Sr calculated from MORB isotopes combined with continental-crust extraction models, as well as "canonical" trace element ratios, to boot-strap the full range of trace element abundances. We show that the single most important factor in determining the ultimate degree of incompatible element depletion in the MORB source lies in the assumptions about the timing of continent extraction, exemplified by continuous extraction versus simple two-stage models. Continued crust extraction generates additional, recent mantle depletion, without affecting the isotopic composition of the residual mantle significantly. Previous emphasis on chemical compositions of MORB and/or peridotites has tended to obscure this. We will explore the effect of different continent extraction models on the degree of U, Th, and K depletion in the MORB source. Given the uncertainties of the two most popular models, the uncertainties of U and Th in DMM are at least ±50%, and this impacts the constraints on the terrestrial Urey ratio. Salters, F.J.M. and Stracke, A., 2004, Geochem. Geophys. Geosyst. 5, Q05004. Workman, R.K. and Hart, S.R., 2005, EPSL 231, 53-72.

  18. Explosion suppression system

    DOEpatents

    Sapko, Michael J.; Cortese, Robert A.

    1992-01-01

    An explosion suppression system and triggering apparatus therefor are provided for quenching gas and dust explosions. An electrically actuated suppression mechanism which dispenses an extinguishing agent into the path ahead of the propagating flame is actuated by a triggering device which is light powered. This triggering device is located upstream of the propagating flame and converts light from the flame to an electrical actuation signal. A pressure arming device electrically connects the triggering device to the suppression device only when the explosion is sensed by a further characteristic thereof beside the flame such as the pioneer pressure wave. The light powered triggering device includes a solar panel which is disposed in the path of the explosion and oriented between horizontally downward and vertical. Testing mechanisms are also preferably provided to test the operation of the solar panel and detonator as well as the pressure arming mechanism.

  19. A worldwide view of groundwater depletion

    NASA Astrophysics Data System (ADS)

    van Beek, L. P.; Wada, Y.; van Kempen, C.; Reckman, J. W.; Vasak, S.; Bierkens, M. F.

    2010-12-01

    During the last decades, global water demand has increased two-fold due to increasing population, expanding irrigated area and economic development. Globally such demand can be met by surface water availability (i.e., water in rivers, lakes and reservoirs) but regional variations are large and the absence of sufficient rainfall and run-off increasingly encourages the use of groundwater resources, particularly in the (semi-)arid regions of the world. Excessive abstraction for irrigation frequently leads to overexploitation, i.e. if groundwater abstraction exceeds the natural groundwater recharge over extensive areas and prolonged times, persistent groundwater depletion may occur. Observations and various regional studies have revealed that groundwater depletion is a substantial issue in regions such as Northwest India, Northeast Pakistan, Central USA, Northeast China and Iran. Here we provide a global overview of groundwater depletion from the year 1960 to 2000 at a spatial resolution of 0.5 degree by assessing groundwater recharge with the global hydrological model PCR-GLOBWB and subtracting estimates of groundwater abstraction obtained from IGRAC-GGIS database. PCR-GLOBWB was forced by the CRU climate dataset downscaled to daily time steps using ERA40 re-analysis data. PCR-GLOBWB simulates daily global groundwater recharge (0.5 degree) while considering sub-grid variability of each grid cell (e.g., short and tall vegetation, different soil types, fraction of saturated soil). Country statistics of groundwater abstraction were downscaled to 0.5 degree by using water demand (i.e., agriculture, industry and domestic) as a proxy. To limit problems related to increased capture of discharge and increased recharge due to groundwater pumping, we restricted our analysis to sub-humid to arid areas. The uncertainty in the resulting estimates was assessed by a Monte Carlo analysis of 100 realizations of groundwater recharge and 100 realizations of groundwater abstraction

  20. Cerebrolysin Attenuates Heat Shock Protein (HSP 72 KD) Expression in the Rat Spinal Cord Following Morphine Dependence and Withdrawal: Possible New Therapy for Pain Management

    PubMed Central

    Sharma, Hari S; Ali, Syed F; Patnaik, Ranjana; Zimmermann-Meinzingen, Sibilla; Sharma, Aruna; Muresanu, Dafin F

    2011-01-01

    The possibility that pain perception and processing in the CNS results in cellular stress and may influence heat shock protein (HSP) expression was examined in a rat model of morphine dependence and withdrawal. Since activation of pain pathways result in exhaustion of growth factors, we examined the influence of cerebrolysin, a mixture of potent growth factors (BDNF, GDNF, NGF, CNTF etc,) on morphine induced HSP expression. Rats were administered morphine (10 mg/kg, s.c. /day) for 12 days and the spontaneous withdrawal symptoms were developed by cessation of the drug administration on day 13th that were prominent on day 14th and continued up to day 15th (24 to 72 h periods). In a separate group of rats, cerebrolysin was infused intravenously (5 ml/kg) once daily from day one until day 15th. In these animals, morphine dependence and withdrawal along with HSP immunoreactivity was examined using standard protocol. In untreated group mild HSP immunoreaction was observed during morphine tolerance, whereas massive upregulation of HSP was seen in CNS during withdrawal phase that correlated well with the withdrawal symptoms and neuronal damage. Pretreatment with cerebrolysin did not affect morphine tolerance but reduced the HSP expression during this phase. Furthermore, cerebrolysin reduced the withdrawal symptoms on day 14th to 15th. Taken together these observations suggest that cellular stress plays an important role in morphine induced pain pathology and exogenous supplement of growth factors, i.e. cerebrolysin attenuates HSP expression in the CNS and induce neuroprotection. This indicates a new therapeutic role of cerebrolysin in the pathophysiology of drugs of abuse, not reported earlier. PMID:21886595

  1. Hydrogen flame suppression by CF{sub 3}I

    SciTech Connect

    Mcllory, A.; Brady, B.; Marshall, P.

    1998-03-01

    Halons have long been the fire suppressants of choice for applications requiring high performance. However, halons are linked to the stratospheric ozone depletion problem. The most common halon, 1301 or CF{sub 3}Br, has an ozone depletion potential (ODP) 11 times higher than the most common chlorofluorocarbon (CFC) refrigerant. This has led to a ban on halon production under the Clean Air Act legislation in the US following the Montreal Protocols on ozone depleting substances. Halon replacements are being actively sought for new fire suppression systems and to retrofit existing systems as the current supply of halons is exhausted. One promising replacement is CF{sub 3}I. This compound has been shown to have fire suppression performance similar to that achieved for halon 1301, but with a very low ODP. Unlike halon 1301, CF{sub 3}I rapidly photolyzes in the troposphere, and thus has a tropospheric lifetime of less than two days. However, CF{sub 3}I is not the perfect replacement; it has performed poorly in cardiac sensitization studies and is approved only for total flooding applications in unoccupied spaces and streaming applications. In this study, they seek to build a model for the suppression of hydrogen fires by CF{sub 3}I. From a fundamental viewpoint, the hydrogen combustion mechanism is appealing because it is the simplest and best characterized of all combustion mechanisms, and an important sub-mechanism of all hydrocarbon combustion mechanisms. Thus, a high-performance hydrogen fire suppressant would almost certainly be an excellent suppressant for most other common fires. One-dimensional, laminar flame calculations are used to determine the major fire suppression mechanisms of CF{sub 3}I. The remainder of the paper is organized as follows: first, the model is described in detail; second, the experimental method and results are presented and finally, the authors compare the model and experimental results and discuss the major reaction pathways and

  2. Entropic depletion in colloidal suspensions and polymer liquids: role of nanoparticle surface topography.

    PubMed

    Banerjee, Debapriya; Yang, Jian; Schweizer, Kenneth S

    2015-12-21

    We employ a hybrid Monte Carlo plus integral equation theory approach to study how dense fluids of small nanoparticles or polymer chains mediate entropic depletion interactions between topographically rough particles where all interaction potentials are hard core repulsion. The corrugated particle surfaces are composed of densely packed beads which present variable degrees of controlled topographic roughness and free volume associated with their geometric crevices. This pure entropy problem is characterized by competing ideal translational and (favorable and unfavorable) excess entropic contributions. Surface roughness generically reduces particle depletion aggregation relative to the smooth hard sphere case. However, the competition between ideal and excess packing entropy effects in the bulk, near the particle surface and in the crevices, results in a non-monotonic variation of the particle-monomer packing correlation function as a function of the two dimensionless length scale ratios that quantify the effective surface roughness. As a result, the inter-particle potential of mean force (PMF), second virial coefficient, and spinodal miscibility volume fraction vary non-monotonically with the surface bead to monomer diameter and particle core to surface bead diameter ratios. A miscibility window is predicted corresponding to an optimum degree of surface roughness that completely destroys depletion attraction resulting in a repulsive PMF. Variation of the (dense) matrix packing fraction can enhance or suppress particle miscibility depending upon the amount of surface roughness. Connecting the monomers into polymer chains destabilizes the system via enhanced contact depletion attraction, but the non-monotonic variations with surface roughness metrics persist. PMID:26411493

  3. Altitude latitude mapping of plasma depletions

    NASA Astrophysics Data System (ADS)

    Rajesh, P.; Liu, J.; Sinha, H.; Banerje, S.

    2007-12-01

    Plasma depletions, if generated at the geomagnetic equator, are expected to appear in the all sky images as dark bands extending pole ward. The all sky observations conducted from Kavalur (12.5¢ªN, 78.8¢ªE; 4.6¢ªN, geomagnetic), INDIA, but showed dark patches in 630.0 nm entering the imager field of view (FOV) from the northern edge in the post-sunset period. These patches gradually extended towards equator and became fully extended dark bands in the North-South direction by midnight. The series of such images appeared to be the airglow signatures of irregularities that are probably generated at off-equatorial latitudes and mapped to the lower or equatorial latitudes. Similar features were observed in several nights. This appearance of depletions as dark patches from the northern edge of the FOV is explained in this work

  4. Replacements For Ozone-Depleting Foaming Agents

    NASA Technical Reports Server (NTRS)

    Blevins, Elana; Sharpe, Jon B.

    1995-01-01

    Fluorinated ethers used in place of chlorofluorocarbons and hydrochlorofluorocarbons. Replacement necessary because CFC's and HCFC's found to contribute to depletion of ozone from upper atmosphere, and manufacture and use of them by law phased out in near future. Two fluorinated ethers do not have ozone-depletion potential and used in existing foam-producing equipment, designed to handle liquid blowing agents soluble in chemical ingredients that mixed to make foam. Any polyurethane-based foams and several cellular plastics blown with these fluorinated ethers used in processes as diverse as small batch pours, large sprays, or double-band lamination to make insulation for private homes, commercial buildings, shipping containers, and storage tanks. Fluorinated ethers proved useful as replacements for CFC refrigerants and solvents.

  5. Tritium transport vessel using depleted uranium

    SciTech Connect

    Heung, L.K.

    1995-10-01

    A tritium transport vessel using depleted uranium was tested in the laboratory using deuterium and protium. The vessel contains 0.5 kg of depleted uranium and can hold up to 18 grams of tritium. The conditions for activation, tritium loading and tritium unloading were defined. The safety aspects that included air-ingress, tritium diffusion, temperature and pressure potentials were evaluated. Air ingress did not cause any temperature surge when the uranium was fully hydrided, but created a temperature peak of 200 {degree}C when the uranium was dehydrided. Accumulation of non-reactive gases such as argon and moisture in the air blocked further air ingress. Only a flow-through type of air ingress could damage the vessel. 6 refs., 9 figs.

  6. Assessment of Preferred Depleted Uranium Disposal Forms

    SciTech Connect

    Croff, A.G.; Hightower, J.R.; Lee, D.W.; Michaels, G.E.; Ranek, N.L.; Trabalka, J.R.

    2000-06-01

    The Department of Energy (DOE) is in the process of converting about 700,000 metric tons (MT) of depleted uranium hexafluoride (DUF6) containing 475,000 MT of depleted uranium (DU) to a stable form more suitable for long-term storage or disposal. Potential conversion forms include the tetrafluoride (DUF4), oxide (DUO2 or DU3O8), or metal. If worthwhile beneficial uses cannot be found for the DU product form, it will be sent to an appropriate site for disposal. The DU products are considered to be low-level waste (LLW) under both DOE orders and Nuclear Regulatory Commission (NRC) regulations. The objective of this study was to assess the acceptability of the potential DU conversion products at potential LLW disposal sites to provide a basis for DOE decisions on the preferred DU product form and a path forward that will ensure reliable and efficient disposal.

  7. Endoplasmic-Reticulum Calcium Depletion and Disease

    PubMed Central

    Mekahli, Djalila; Bultynck, Geert; Parys, Jan B.; De Smedt, Humbert; Missiaen, Ludwig

    2011-01-01

    The endoplasmic reticulum (ER) as an intracellular Ca2+ store not only sets up cytosolic Ca2+ signals, but, among other functions, also assembles and folds newly synthesized proteins. Alterations in ER homeostasis, including severe Ca2+ depletion, are an upstream event in the pathophysiology of many diseases. On the one hand, insufficient release of activator Ca2+ may no longer sustain essential cell functions. On the other hand, loss of luminal Ca2+ causes ER stress and activates an unfolded protein response, which, depending on the duration and severity of the stress, can reestablish normal ER function or lead to cell death. We will review these various diseases by mainly focusing on the mechanisms that cause ER Ca2+ depletion. PMID:21441595

  8. Copenhagen delegates advance phaseout of ozone depleters

    SciTech Connect

    Kirschner, E.

    1992-12-09

    As expected, delegates at the United Nations Ozone Layer Conference in Copenhagen sped up ozone depleter phaseouts from the 1987 Montreal Protocol and the 1990 London amendments. The changes bring the worldwide production phaseout of chlorofluorocarbons (CFCs) and other ozone depleters in developed countries in line with U.S. and European plans announced earlier this year. Adjustments to the protocol, which are binding on the signatories, change the phaseout for CFC, carbon tetrachloride, and methyl chloroform production and consumption to January 1, 1996 from 2000. The 75% reduction of 1986 levels from CFCs by January 1, 1994 is a compromise between European pressure for an 85% cut and the US goal of 70%. Halon production is to end January 1, 1994, as anticipated. Developing countries continue to have a 10-year grace period. Friends of the Earth ozone campaign director Liz Cook counters that the phaseout dates were scheduled with concern for the chemical industry, not for the ozone layer.

  9. The ultimate disposition of depleted uranium

    SciTech Connect

    Lemons, T.R.

    1991-12-31

    Depleted uranium (DU) is produced as a by-product of the uranium enrichment process. Over 340,000 MTU of DU in the form of UF{sub 6} have been accumulated at the US government gaseous diffusion plants and the stockpile continues to grow. An overview of issues and objectives associated with the inventory management and the ultimate disposition of this material is presented.

  10. The ultimate disposition of depleted uranium

    SciTech Connect

    Not Available

    1990-12-01

    Significant amounts of the depleted uranium (DU) created by past uranium enrichment activities have been sold, disposed of commercially, or utilized by defense programs. In recent years, however, the demand for DU has become quite small compared to quantities available, and within the US Department of Energy (DOE) there is concern for any risks and/or cost liabilities that might be associated with the ever-growing inventory of this material. As a result, Martin Marietta Energy Systems, Inc. (Energy Systems), was asked to review options and to develop a comprehensive plan for inventory management and the ultimate disposition of DU accumulated at the gaseous diffusion plants (GDPs). An Energy Systems task team, under the chairmanship of T. R. Lemons, was formed in late 1989 to provide advice and guidance for this task. This report reviews options and recommends actions and objectives in the management of working inventories of partially depleted feed (PDF) materials and for the ultimate disposition of fully depleted uranium (FDU). Actions that should be considered are as follows. (1) Inspect UF{sub 6} cylinders on a semiannual basis. (2) Upgrade cylinder maintenance and storage yards. (3) Convert FDU to U{sub 3}O{sub 8} for long-term storage or disposal. This will include provisions for partial recovery of costs to offset those associated with DU inventory management and the ultimate disposal of FDU. Another recommendation is to drop the term tails'' in favor of depleted uranium'' or DU'' because the tails'' label implies that it is waste.'' 13 refs.

  11. Depletion modeling of liquid dominated geothermal reservoirs

    SciTech Connect

    Olsen, G.

    1984-06-01

    Depletion models for liquid-dominated geothermal reservoirs are derived and presented. The depletion models are divided into two categories: confined and unconfined. For both cases depletion models with no recharge (or influx), and depletion models including recharge, are used to match field data from the Svartsengi high temperature geothermal field in Iceland. The influx models included with the mass and energy balances are adopted from the petroleum engineering literature. The match to production data from Svartsengi is improved when influx was included. The Schilthuis steady-state influx gives a satisfactory match. The finite aquifer method of Fetkovitch, and the unsteady state method of Hurst gave reasonable answers, but not as good. The best match is obtained using Hurst simplified solution when lambda = 1.3 x 10{sup -4} m{sup -1}. From the match the cross-sectional area of the aquifer was calculated as 3.6 km{sup 2}. The drawdown was predicted using the Hurst simplified method, and compared with predicted drawdown from a boiling model and an empirical log-log model. A large difference between the models was obtained. The predicted drawdown using the Hurst simplified method falls between the other two. Injection has been considered by defining the net rate as being the production rate minus the injection rate. No thermal of transient effects were taken into account. Prediction using three different net rates shows that the pressure can be maintained using the Hurst simplified method if there is significant fluid reinjection. 32 refs., 44 figs., 2 tabs.

  12. Carbon sequestration in depleted oil shale deposits

    SciTech Connect

    Burnham, Alan K; Carroll, Susan A

    2014-12-02

    A method and apparatus are described for sequestering carbon dioxide underground by mineralizing the carbon dioxide with coinjected fluids and minerals remaining from the extraction shale oil. In one embodiment, the oil shale of an illite-rich oil shale is heated to pyrolyze the shale underground, and carbon dioxide is provided to the remaining depleted oil shale while at an elevated temperature. Conditions are sufficient to mineralize the carbon dioxide.

  13. Photoimmune suppression and photocarcinogenesis.

    PubMed

    Ullrich, Stephen E

    2002-03-01

    The primary cause of non-melanoma skin cancer, the most prevalent form of human neoplasia, is the ultraviolet (UV) radiation found in sunlight. Exposing mice to UV radiation induces skin cancers that are highly antigenic. Upon transfer of an UV-induced skin cancer to a normal syngeneic mouse, the tumor cells are recognized and rapidly destroyed by the immune system of the recipient. This raises the question of how these cancers avoided immune destruction during their development in the UV-irradiated host. This question was answered when it was discovered that in addition to being carcinogenic, UV radiation was also immunosuppressive. Studies with immune suppressed transplantation recipients, and biopsy proven skin cancer patients have confirmed that UV-induced immune suppression is a risk factor for skin cancer development in humans. It is of great importance, therefore, to understand the mechanisms underlying UV-induced immune suppression. The focus of this manuscript will be to use some examples from the more recent scientific literature to review the mechanisms by which UV radiation suppresses the immune response and allows for the progressive outgrowth of antigenic skin tumors. PMID:11861222

  14. Parasitic suppressing circuit

    NASA Technical Reports Server (NTRS)

    Fowler, J. T.; Raposa, F. L. (Inventor)

    1973-01-01

    A circuit for suppressing parasitic oscillations across an inductor operating in a resonant mode is described. The circuit includes a switch means and resistive means connected serially across the inductor. A unidirectional resistive-capacitive network is also connected across the inductor and to the switch means to automatically render the switch means conducting when inductive current through the inductor ceases to flow.

  15. Rapid induction of Alternative Lengthening of Telomeres by depletion of the histone chaperone ASF1

    PubMed Central

    O’Sullivan, Roderick J.; Arnoult, Nausica; Lackner, Daniel H.; Oganesian, Liana; Haggblom, Candy; Corpet, Armelle; Almouzni, Genevieve; Karlseder, Jan

    2013-01-01

    The mechanism of activation of the Alternative Lengthening of Telomeres (ALT) pathway of mammalian chromosome end maintenance has remained an unresolved issue. We have discovered that co-depletion of the histone chaperones ASF1a and ASF1b in human cells induced all hallmarks of ALT in both primary and cancer cells. These included the formation of ALT associated PML bodies (APBs), extra-chromosomal telomeric DNA species an elevated frequency of telomeric sister chromatid exchanges (t-SCE) events and inter-telomeric exchange of an integrated tag. The induction of ALT characteristics in this setting led to the simultaneous suppression of telomerase. We identified that ALT induction is positively regulated by RAD17 and BLM, while negatively regulated by EXO1 and DNA2. The induction of ALT phenotypes as a consequence of ASF1 depletion strongly support the hypothesis that ALT is a consequence of a histone management dysfunction. PMID:24413054

  16. Evaluation of SDS depletion using an affinity spin column and IMS-MS detection

    SciTech Connect

    Hengel, Shawna M.; Floyd, Erica A.; Baker, Erin Shammel; Zhao, Rui; Wu, Si; Pasa-Tolic, Ljiljana

    2012-11-01

    While the use of detergents is necessary for a variety of protein isolation preparation protocols, often prior to mass spectral (MS) analysis, they are not compatible with MS analysis due to ion suppression and adduct formation. This manuscript describes optimization of detergent removal, using commercially available SDS depletion spin columns containing an affinity resin, providing for both increased protein recovery and thorough SDS removal. Ion mobility spectrometry coupled with mass spectrometry (IMS-MS) allowed for a concurrent analysis of both analyte and detergent. In the case of both proteins and peptides, higher detergent concentrations than previously reported provided an increase of sample recovery; however there was a limit as SDS was detected by IMS-MS at higher levels of SDS indicating incomplete detergent depletion. The results also suggest optimal conditions for SDS removal are dependent on the sample concentration. Overall, this study provides a useful guide for proteomic studies where SDS is required for efficient sample preparation.

  17. Pumping test evaluation of stream depletion parameters.

    PubMed

    Lough, Hilary K; Hunt, Bruce

    2006-01-01

    Descriptions are given of a pumping test and a corresponding analysis that permit calculation of all five hydrogeological parameters appearing in the Hunt (2003) solution for stream depletion caused by ground water abstraction from a well beside a stream. This solution assumes that flow in the pumped aquifer is horizontal, flow in the overlying aquitard or system of aquitards is vertical, and the free surface in the top aquitard is allowed to draw down. The definition of an aquitard in this paper is any layer with a vertical hydraulic conductivity much lower than the horizontal hydraulic conductivity of the pumped aquifer. These "aquitards" may be reasonably permeable layers but are distinguished from the pumped aquifer by their hydraulic conductivity contrast. The pumping test requires a complete set of drawdown measurements from at least one observation well. This well must be deep enough to penetrate the pumped aquifer, and pumping must continue for a sufficient time to ensure that depleted streamflow becomes a significant portion of the well abstraction rate. Furthermore, two of the five parameters characterize an aquitard that overlies the pumped aquifer, and values for these parameters are seen to be dependent upon the initial water table elevation in the aquitard. The field test analyzed herein used a total of eight observation wells screened in the pumped aquifer, and measurements from these wells gave eight sets of parameters that are used in a sensitivity analysis to determine the relative importance of each parameter in the stream depletion calculations. PMID:16857031

  18. Record Arctic ozone depletion could occur again

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-02-01

    In the winter of 2010-2011, ozone levels above the Arctic declined to record lows, creating the first Arctic ozone hole, similar to the well-known Antarctic ozone hole. Scientists believe the ozone depletion was due partly to unusually cold temperatures in the stratosphere above the Arctic, as colder stratospheric temperatures make ozone-destroying chemicals such as chlorine more active. As global climate change continues, the Arctic stratosphere is expected to get colder, but levels of ozone-destroying chemicals should decline, as emissions of these chemicals were banned by the Montreal Protocol. To try to learn more about Arctic ozone dynamics and determine whether the Arctic ozone hole is likely to recur, Sinnhuber et al. looked at satellite observations of temperature, ozone, water vapor, and chemicals that affect ozone in the Arctic atmosphere. They also used a model to determine how sensitive ozone levels are to stratospheric temperatures and chemistry. They found that their model accurately reproduced measured conditions. Their model suggests that stratospheric temperatures 1°C lower than in the 2010-2011 winter would result in locally nearly complete ozone depletion in the Arctic lower stratosphere with current levels of chemicals. A 10% reduction in ozone-depleting chemicals would be offset by a 1°C decrease in stratospheric temperatures.

  19. Antarctic springtime depletion of atmospheric mercury.

    PubMed

    Ebinghaus, Ralf; Kock, Hans H; Temme, Christian; Einax, Jürgen W; Lowe, Astrid G; Richter, Andreas; Burrows, John P; Schroeder, William H

    2002-03-15

    Unlike other heavy metals that are inherently associated with atmospheric aerosols, mercury in ambient air exists predominantly in the gaseous elemental form. Because of its prolonged atmospheric residence time, elemental mercury vapor is distributed on a global scale. Recently, Canadian researchers have discovered that total gaseous mercury levels in the lower tropospheric boundary layer in the Canadian Arctic are often significantly depleted during the months after polar sunrise. A possible explanation may involve oxidation of elemental mercury, followed by adsorption and deposition of the oxidized form, leading to an increased input of atmospheric mercury into the Arctic ecosystem. Here we present the first continuous high-time-resolution measurements of total gaseous mercury in the Antarctic covering a 12-month period between January 2000 and January 2001 at the German Antarctic research station Neumayer (70 degrees 39' S, 8 degrees 15' W). We report that mercury depletion events also occur in the Antarctic after polar sunrise and compare our measurements with a data setfrom Alert, Nunavut, Canada. We also present indications that BrO radicals and ozone play a key role in the boundary-layer chemistry during springtime mercury depletion events in the Antarctic troposphere. PMID:11944675

  20. Targeted Proapoptotic Peptides Depleting Adipose Stromal Cells Inhibit Tumor Growth.

    PubMed

    Daquinag, Alexes C; Tseng, Chieh; Zhang, Yan; Amaya-Manzanares, Felipe; Florez, Fernando; Dadbin, Ali; Zhang, Tao; Kolonin, Mikhail G

    2016-02-01

    Progression of many cancers is associated with tumor infiltration by mesenchymal stromal cells (MSC). Adipose stromal cells (ASC) are MSC that serve as adipocyte progenitors and endothelium-supporting cells in white adipose tissue (WAT). Clinical and animal model studies indicate that ASC mobilized from WAT are recruited by tumors. Direct evidence for ASC function in tumor microenvironment has been lacking due to unavailability of approaches to specifically inactivate these cells. Here, we investigate the effects of a proteolysis-resistant targeted hunter-killer peptide D-WAT composed of a cyclic domain CSWKYWFGEC homing to ASC and of a proapoptotic domain KLAKLAK2. Using mouse bone marrow transplantation models, we show that D-WAT treatment specifically depletes tumor stromal and perivascular cells without directly killing malignant cells or tumor-infiltrating leukocytes. In several mouse carcinoma models, targeted ASC cytoablation reduced tumor vascularity and cell proliferation resulting in hemorrhaging, necrosis, and suppressed tumor growth. We also validated a D-WAT derivative with a proapoptotic domain KFAKFAK2 that was found to have an improved cytoablative activity. Our results for the first time demonstrate that ASC, recruited as a component of tumor microenvironment, support cancer progression. We propose that drugs targeting ASC can be developed as a combination therapy complementing conventional cancer treatments. PMID:26316391

  1. Metabolic Effects of Acute Thiamine Depletion Are Reversed by Rapamycin in Breast and Leukemia Cells

    PubMed Central

    Liu, Shuqian; Miriyala, Sumitra; Keaton, Mignon A.; Jordan, Craig T.; Wiedl, Christina; Clair, Daret K. St.; Moscow, Jeffrey A.

    2014-01-01

    Thiamine-dependent enzymes (TDEs) control metabolic pathways that are frequently altered in cancer and therefore present cancer-relevant targets. We have previously shown that the recombinant enzyme thiaminase cleaves and depletes intracellular thiamine, has growth inhibitory activity against leukemia and breast cancer cell lines, and that its growth inhibitory effects were reversed in leukemia cell lines by rapamycin. Now, we first show further evidence of thiaminase therapeutic potential by demonstrating its activity against breast and leukemia xenografts, and against a primary leukemia xenograft. We therefore further explored the metabolic effects of thiaminase in combination with rapamycin in leukemia and breast cell lines. Thiaminase decreased oxygen consumption rate and increased extracellular acidification rate, consistent with the inhibitory effect of acute thiamine depletion on the activity of the TDEs pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase complexes; these effects were reversed by rapamycin. Metabolomic studies demonstrated intracellular thiamine depletion and the presence of the thiazole cleavage product in thiaminase-treated cells, providing validation of the experimental procedures. Accumulation of ribose and ribulose in both cell lines support the thiaminase-mediated suppression of the TDE transketolase. Interestingly, thiaminase suppression of another TDE, branched chain amino ketoacid dehydrogenase (BCKDH), showed very different patterns in the two cell lines: in RS4 leukemia cells it led to an increase in BCKDH substrates, and in MCF-7 breast cancer cells it led to a decrease in BCKDH products. Immunoblot analyses showed corresponding differences in expression of BCKDH pathway enzymes, and partial protection of thiaminase growth inhibition by gabapentin indicated that BCKDH inhibition may be a mechanism of thiaminase-mediated toxicity. Surprisingly, most of thiaminase-mediated metabolomic effects were also reversed by rapamycin

  2. Bragg Spectroscopy of a Strongly-Interacting Homogeneous BEC: probing quantum depletion

    NASA Astrophysics Data System (ADS)

    Lopes, Raphael; Eigen, Christoph; Baker, Adam; Navon, Nir; Hadzibabic, Zoran; Smith, Robert

    2016-05-01

    We will present Bragg spectroscopy measurements performed on a homogeneous Bose-Einstein condensate (BEC) as a function of interaction strength. The width and position of the Bragg resonance reveal the momentum distribution and energy shift of the ground state, respectively. We observe that the width increases as a function of interaction strength and interpret this behavior as a result of quantum depletion of the condensate, induced by interactions. The central frequency of the resonance grows linearly with the interaction strength (mean-field behavior) but is reduced as the interaction strength further increases; being completely suppressed at high values.

  3. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...,” and “minerals,” see paragraph (d) of § 1.611-1. (b) Denial of percentage depletion in case of oil and... 26 Internal Revenue 7 2014-04-01 2013-04-01 true Percentage depletion; general rule. 1.613-1... TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion;...

  4. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...,” and “minerals,” see paragraph (d) of § 1.611-1. (b) Denial of percentage depletion in case of oil and... 26 Internal Revenue 7 2012-04-01 2012-04-01 false Percentage depletion; general rule. 1.613-1... TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion;...

  5. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...,” and “minerals,” see paragraph (d) of § 1.611-1. (b) Denial of percentage depletion in case of oil and... 26 Internal Revenue 7 2013-04-01 2013-04-01 false Percentage depletion; general rule. 1.613-1... TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion;...

  6. 26 CFR 1.642(e)-1 - Depreciation and depletion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Depreciation and depletion. 1.642(e)-1 Section 1... (CONTINUED) INCOME TAXES Estates, Trusts, and Beneficiaries § 1.642(e)-1 Depreciation and depletion. An estate or trust is allowed the deductions for depreciation and depletion, but only to the extent...

  7. Children's Models of the Ozone Layer and Ozone Depletion.

    ERIC Educational Resources Information Center

    Christidou, Vasilia; Koulaidis, Vasilis

    1996-01-01

    The views of 40 primary students on ozone and its depletion were recorded through individual, semi-structured interviews. The data analysis resulted in the formation of a limited number of models concerning the distribution and role of ozone in the atmosphere, the depletion process, and the consequences of ozone depletion. Identifies five target…

  8. Cancer suppression by compression.

    PubMed

    Frieden, B Roy; Gatenby, Robert A

    2015-01-01

    Recent experiments indicate that uniformly compressing a cancer mass at its surface tends to transform many of its cells from proliferative to functional forms. Cancer cells suffer from the Warburg effect, resulting from depleted levels of cell membrane potentials. We show that the compression results in added free energy and that some of the added energy contributes distortional pressure to the cells. This excites the piezoelectric effect on the cell membranes, in particular raising the potentials on the membranes of cancer cells from their depleted levels to near-normal levels. In a sample calculation, a gain of 150 mV in is so attained. This allows the Warburg effect to be reversed. The result is at least partially regained function and accompanying increased molecular order. The transformation remains even when the pressure is turned off, suggesting a change of phase; these possibilities are briefly discussed. It is found that if the pressure is, in particular, applied adiabatically the process obeys the second law of thermodynamics, further validating the theoretical model. PMID:25520262

  9. Pressure suppression containment system

    DOEpatents

    Gluntz, Douglas M.; Townsend, Harold E.

    1994-03-15

    A pressure suppression containment system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The wetwell pool includes a plenum for receiving the non-condensable gas carried with steam from the drywell following a loss-of coolant-accident (LOCA). The wetwell plenum is vented to a plenum above the GDCS pool following the LOCA for suppressing pressure rise within the containment vessel. A method of operation includes channeling steam released into the drywell following the LOCA into the wetwell pool for cooling along with the non-condensable gas carried therewith. The GDCS pool is then drained by gravity, and the wetwell plenum is vented into the GDCS plenum for channeling the non-condensable gas thereto.

  10. Pressure suppression containment system

    DOEpatents

    Gluntz, D.M.; Townsend, H.E.

    1994-03-15

    A pressure suppression containment system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The wetwell pool includes a plenum for receiving the non-condensable gas carried with steam from the drywell following a loss-of-coolant-accident (LOCA). The wetwell plenum is vented to a plenum above the GDCS pool following the LOCA for suppressing pressure rise within the containment vessel. A method of operation includes channeling steam released into the drywell following the LOCA into the wetwell pool for cooling along with the non-condensable gas carried therewith. The GDCS pool is then drained by gravity, and the wetwell plenum is vented into the GDCS plenum for channeling the non-condensable gas thereto. 6 figures.

  11. Vibrotactile suppression of tinnitus

    NASA Astrophysics Data System (ADS)

    Lenhardt, Martin L.

    2002-05-01

    At the Society's 142nd meeting, the efficacy of high frequency bone conducted stimulation in suppressing tinnitus was presented. The hypothesized mechanism was the reprogramming of frequency tuning of auditory neurons in the central nervous system, secondarily to peripheral hearing loss. This mechanism is unlikely in cases of tinnitus in the presence of normal audiometric sensitivity. There is the possibility that hearing loss above 10 kHz can play a role in tinnitus, an association not thoroughly explored. Somatomotor stimulation influencing the quality of tinnitus has been reported, as have interconnections of the auditory and somatosensory systems. There would appear to be an evolutionary advantage of linking the sensorimotor organization of the external ear and the auditory function of the brainstem in sound localization. Thus, stimulation of the pinna and post auricular area may be a means of suppressing tinnitus. To that end a thin aluminum ceramic bimorph was constructed to fit on the inner surface of the pinna. When driven by low (<100 Hz) and high (>10 kHz) frequencies multiplied by MHz carriers, demodulation in the skin resulted in vibrotactile stimulation. Tactile stimulation was an adjunct to the high frequencies resulting in a multimodal suppressive effect in a small pilot study.

  12. Menstrual suppression: current perspectives

    PubMed Central

    Hillard, Paula Adams

    2014-01-01

    Menstrual suppression to provide relief of menstrual-related symptoms or to manage medical conditions associated with menstrual morbidity or menstrual exacerbation has been used clinically since the development of steroid hormonal therapies. Options range from the extended or continuous use of combined hormonal oral contraceptives, to the use of combined hormonal patches and rings, progestins given in a variety of formulations from intramuscular injection to oral therapies to intrauterine devices, and other agents such as gonadotropin-releasing hormone (GnRH) antagonists. The agents used for menstrual suppression have variable rates of success in inducing amenorrhea, but typically have increasing rates of amenorrhea over time. Therapy may be limited by side effects, most commonly irregular, unscheduled bleeding. These therapies can benefit women’s quality of life, and by stabilizing the hormonal milieu, potentially improve the course of underlying medical conditions such as diabetes or a seizure disorder. This review addresses situations in which menstrual suppression may be of benefit, and lists options which have been successful in inducing medical amenorrhea. PMID:25018654

  13. Mode of ATM-dependent suppression of chromosome translocation

    SciTech Connect

    Yamauchi, Motohiro; Suzuki, Keiji; Oka, Yasuyoshi; Suzuki, Masatoshi; Kondo, Hisayoshi; Yamashita, Shunichi

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer We addressed how ATM suppresses frequency of chromosome translocation. Black-Right-Pointing-Pointer We found ATM/p53-dependent G1 checkpoint suppresses translocation frequency. Black-Right-Pointing-Pointer We found ATM and DNA-PKcs function in a common pathway to suppress translocation. -- Abstract: It is well documented that deficiency in ataxia telangiectasia mutated (ATM) protein leads to elevated frequency of chromosome translocation, however, it remains poorly understood how ATM suppresses translocation frequency. In the present study, we addressed the mechanism of ATM-dependent suppression of translocation frequency. To know frequency of translocation events in a whole genome at once, we performed centromere/telomere FISH and scored dicentric chromosomes, because dicentric and translocation occur with equal frequency and by identical mechanism. By centromere/telomere FISH analysis, we confirmed that chemical inhibition or RNAi-mediated knockdown of ATM causes 2 to 2.5-fold increase in dicentric frequency at first mitosis after 2 Gy of gamma-irradiation in G0/G1. The FISH analysis revealed that ATM/p53-dependent G1 checkpoint suppresses dicentric frequency, since RNAi-mediated knockdown of p53 elevated dicentric frequency by 1.5-fold. We found ATM also suppresses dicentric occurrence independently of its checkpoint role, as ATM inhibitor showed additional effect on dicentric frequency in the context of p53 depletion and Chk1/2 inactivation. Epistasis analysis using chemical inhibitors revealed that ATM kinase functions in the same pathway that requires kinase activity of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to suppress dicentric frequency. From the results in the present study, we conclude that ATM minimizes translocation frequency through its commitment to G1 checkpoint and DNA double-strand break repair pathway that requires kinase activity of DNA-PKcs.

  14. [Mitochondrial disease and mitochondrial DNA depletion syndromes].

    PubMed

    Huang, Chin-Chang; Hsu, Chang-Huang

    2009-12-01

    Mitochondria is an intracellular double membrane-bound structure and it can provide energy for intracellular metabolism. The metabolism includes Krebs cycle, beta-oxidation and lipid synthesis. The density of mitochondria is different in various tissues dependent upon the demands of oxidative phosphorylation. Mitochondrial diseases can occur by defects either in mitochondrial DNA or nuclear DNA. Human mitochondrial DNA (mtDNA) encoding for 22 tRNAs, 2 rRNAs and 13 mRNAs that are translated in the mitochondria. Mitochondrial genetic diseases are most resulted from defects in the mtDNA which may be point mutations, deletions, or mitochondrial DNA depletion. These patterns of inheritance in mitochondrial diseases include sporadic, maternally inherited, or of Mendelian inheritance. Mitochondrial DNA depletion is caused by defects in the nuclear genes that are responsible for maintenance of integrity of mtDNA or deoxyribonucelotide pools and mtDNA biogenesis. The mtDNA depletion syndrome (MDS) includes the following categories: progressive external ophthalmoplegia (PEO), predominant myopathy, mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), sensory-ataxic neuropathy, dysarthria, and ophthalmoplegia (SANDO) and hepato-encephalopathy. The most common tissues or organs involved in MDS and related disorders include the brain, liver and muscles. These involved genes are divided into two groups including 1) DNA polymerase gamma (POLG, POLG2) and Twinkle genes whose products function directly at the mtDNA replication fork, and 2) adenine nucleotide translocator 1, thymidine phosphorylase, thymidine kinase 2, deoxyguanosine kinase, ADP-forming succinyl-CoA synthetase ligase, MPV17 whose products supply the mitochondria with deoxyribonucleotide triphosphate pools needed for mtDNA replication, and possible mutation in the RRM2B gene. The development has provided new information about the importance of the biosynthetic pathway of the nucleotides for mtDNA replication

  15. A modern depleted uranium manufacturing facility

    SciTech Connect

    Zagula, T.A.

    1995-07-01

    The Specific Manufacturing Capabilities (SMC) Project located at the Idaho National Engineering Laboratory (INEL) and operated by Lockheed Martin Idaho Technologies Co. (LMIT) for the Department of Energy (DOE) manufactures depleted uranium for use in the U.S. Army MIA2 Abrams Heavy Tank Armor Program. Since 1986, SMC has fabricated more than 12 million pounds of depleted uranium (DU) products in a multitude of shapes and sizes with varying metallurgical properties while maintaining security, environmental, health and safety requirements. During initial facility design in the early 1980`s, emphasis on employee safety, radiation control and environmental consciousness was gaining momentum throughout the DOE complex. This fact coupled with security and production requirements forced design efforts to focus on incorporating automation, local containment and computerized material accountability at all work stations. The result was a fully automated production facility engineered to manufacture DU armor packages with virtually no human contact while maintaining security, traceability and quality requirements. This hands off approach to handling depleted uranium resulted in minimal radiation exposures and employee injuries. Construction of the manufacturing facility was complete in early 1986 with the first armor package certified in October 1986. Rolling facility construction was completed in 1987 with the first certified plate produced in the fall of 1988. Since 1988 the rolling and manufacturing facilities have delivered more than 2600 armor packages on schedule with 100% final product quality acceptance. During this period there was an annual average of only 2.2 lost time incidents and a single individual maximum radiation exposure of 150 mrem. SMC is an example of designing and operating a facility that meets regulatory requirements with respect to national security, radiation control and personnel safety while achieving production schedules and product quality.

  16. Zn2+ depletion blocks endosome fusion.

    PubMed Central

    Aballay, A; Sarrouf, M N; Colombo, M I; Stahl, P D; Mayorga, L S

    1995-01-01

    Fusion among endosomes is an important step for transport and sorting of internalized macromolecules. Working in a cell-free system, we previously reported that endosome fusion requires cytosol and ATP, and is sensitive to N-ethylmaleimide. Fusion is regulated by monomeric and heterotrimeric GTP-binding proteins. We now report that fusion can proceed at very low Ca2+ concentrations, i.e. < 30 nM. Moreover, fusion is not affected when intravesicular Ca2+ is depleted by preincubation of vesicles with calcium ionophores (5 microM ionomycin or A23187) in the presence of calcium chelators (5 mM EGTA or 60 mM EDTA). The results indicate that fusion can proceed at extremely low concentrations of intravesicular and extravesicular Ca2+. However, BAPTA [1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid], a relatively specific Ca2+ chelator, inhibits fusion. BAPTA binds other metals besides Ca2+. We present evidence that BAPTA inhibition is due not to Ca2+ chelation but to Zn2+ depletion. TPEN [N,N,N',N'-tetrakis-(2-pyridylmethyl) ethylenediamine], another metal-ion chelator with low affinity for Ca2+, also inhibited fusion. TPEN- and BAPTA-inhibited fusions were restored by addition of Zn2+. Zn(2+)-dependent fusion presents the same characteristics as control fusion. In intact cells, TPEN inhibited transport along the endocytic pathway. The results indicate that Zn2+ depletion blocks endosome fusion, suggesting that this ion is necessary for the function of one or more factors involved in the fusion process. Images Figure 1 PMID:8554539

  17. Rhenium Disulfide Depletion-Load Inverter

    NASA Astrophysics Data System (ADS)

    McClellan, Connor; Corbet, Chris; Rai, Amritesh; Movva, Hema C. P.; Tutuc, Emanuel; Banerjee, Sanjay K.

    2015-03-01

    Many semiconducting Transition Metal Dichalcogenide (TMD) materials have been effectively used to create Field-Effect Transistor (FET) devices but have yet to be used in logic designs. We constructed a depletion-load voltage inverter using ultrathin layers of Rhenium Disulfide (ReS2) as the semiconducting channel. This ReS2 inverter was fabricated on a single micromechanically-exfoliated flake of ReS2. Electron beam lithography and physical vapor deposition were used to construct Cr/Au electrical contacts, an Alumina top-gate dielectric, and metal top-gate electrodes. By using both low (Aluminum) and high (Palladium) work-function metals as two separate top-gates on a single ReS2 flake, we create a dual-gated depletion mode (D-mode) and enhancement mode (E-mode) FETs in series. Both FETs displayed current saturation in the output characteristics as a result of the FET ``pinch-off'' mechanism and On/Off current ratios of 105. Field-effect mobilities of 23 and 17 cm2V-1s-1 and subthreshold swings of 97 and 551 mV/decade were calculated for the E-mode and D-mode FETs, respectively. With a supply voltage of 1V, at low/negative input voltages the inverter output was at a high logic state of 900 mV. Conversely with high/positive input voltages, the inverter output was at a low logic state of 500 mV. The inversion of the input signal demonstrates the potential for using ReS2 in future integrated circuit designs and the versatility of depletion-load logic devices for TMD research. NRI SWAN Center and ARL STTR Program.

  18. SVARTSENGI FIELD PRODUCTION DATA AND DEPLETION ANALYSIS

    SciTech Connect

    Gudmundsson, J.S.; Thorhallsson, O.S.

    1985-01-22

    There have been two major high-temperature geothermal field developments in Iceland in the last decade; Krafla in the north-east, and Svartsengi in the south-west. These and other geothermal developments have recently been reported by Palmason et al. The Krafla field will not be discussed here, but details about the field are available in Stefansson and the power plant in Eliasson et al. Several reservoir engineering studies of the Krafla field have been published. The Svartsengi field is one of several fields on the Reykjanes Peninsula in south-west Iceland. About 15 km west of Svartsengi, on the tip of the Peninsula, the Reykjanes field is now under development, primarily for seawater chemicals production. The recently drilled Eldvorp field is located in line between these two fields, about 5 km west of Svartsengi. There are also several fields to the east of Svartsengi, at 15-20 km distance. The Svartsengi, Eldvorp, and Reykjanes fields exist in the same tectonic-volcanic environment, and are surrounded by similar geohydrological conditions, as discussed by Georgsson; see also Gudmundsson et al. and Franzson. Optimum development of these and other fields on the Reykjanes Peninsula, requires an understanding of their depletion behavior with time; that is, how the reservoir pressure falls with production. While recognizing that no two geothermal fields are alike, we also realize that an understanding of the depletion behavior of Svartsengi, for example, may prove useful in the development of other similar and nearby fields. The main purpose of this paper is to report our depletion analysis of the Svartsengi field using lumped-parameter and water influx modeling: we also report the field's production history.

  19. Modelling CO depletion in starless cores

    NASA Astrophysics Data System (ADS)

    Rawlings, Jonathan M. C.

    In recent years there has been a dramatic increase in the observational detection of molecular depletion in star-forming dark clouds. In many cases the data is of very high quality and what was once considered a rather hypothetical process is now almost universally accepted as a (the) major cause of the presence of emission 'holes' in molecular maps of dense cores. However, the interpretation of the data can be severely undermined by uncertainties in the physics and chemistry. This is particularly true in the case of general molecular studies of active star-forming regions. For these objects there exist strong degeneracies between various chemical effects (gas-phase time-dependencies, desorption processes and efficiencies, ionization rates etc.) and poorly constrained physics (most particularly in the assumed kinematics and evolutionary history). Whilst these problems result in unacceptable ambiguities in the case of evolved sources, we can make significant progress for young, near-static cores and using molecular species with simple chemistries. A considerable set of constraints on the free parameters is now provided by the extensive sub-millimetre continuum and infra-red absorption studies of starless cores. These observations give us good descriptions of the temperature and density profiles in these sources. Moreover CO is to a large extent chemically inert, so that any decline of abundance at high densities can (primarily) be interpreted as being a consequence of freeze-out. Thus there are only two major free parameters:- the net depletion/desorption rate and the chemical age of the source. In this study CO abundance profiles are calculated as a function of time for cores whose temperature and density profiles have already been determined. The results are corrected for excitation effects and converted to synthetic maps, assuming typical single-dish beam parameters and source characteristics. A strong correlation with existing depletion maps is found and strong

  20. Simulation of polar ozone depletion: An update

    NASA Astrophysics Data System (ADS)

    Solomon, Susan; Kinnison, Doug; Bandoro, Justin; Garcia, Rolando

    2015-08-01

    We evaluate polar ozone depletion chemistry using the specified dynamics version of the Whole Atmosphere Community Climate Model for the year 2011. We find that total ozone depletion in both hemispheres is dependent on cold temperatures (below 192 K) and associated heterogeneous chemistry on polar stratospheric cloud particles. Reactions limited to warmer temperatures above 192 K, or on binary liquid aerosols, yield little modeled polar ozone depletion in either hemisphere. An imposed factor of three enhancement in stratospheric sulfate increases ozone loss by up to 20 Dobson unit (DU) in the Antarctic and 15 DU in the Arctic in this model. Such enhanced sulfate loads are similar to those observed following recent relatively small volcanic eruptions since 2005 and imply impacts on the search for polar ozone recovery. Ozone losses are strongly sensitive to temperature, with a test case cooler by 2 K producing as much as 30 DU additional ozone loss in the Antarctic and 40 DU in the Arctic. A new finding of this paper is the use of the temporal behavior and variability of ClONO2 and HCl as indicators of the efficacy of heterogeneous chemistry. Transport of ClONO2 from the southern subpolar regions near 55-65°S to higher latitudes near 65-75°S provides a flux of NOx from more sunlit latitudes to the edge of the vortex and is important for ozone loss in this model. Comparisons between modeled and observed total column and profile ozone perturbations, ClONO2 abundances, and the rate of change of HCl bolster confidence in these conclusions.

  1. Ozone depletion: implications for the veterinarian.

    PubMed

    Kopecky, K E

    1978-09-15

    Man has inadvertently modified the stratosphere. There is a good possibility that the ozone layer is being depleted by the use of jet aircraft (SST), chlorofluoromethane propellants, and nitrogen fertilizers. Under unpolluted conditions, the production of ozone equals its destruction. By man's intervention, however, the destruction may exceed the production. The potential outcome is increased intensity of solar ultraviolet (280-400 nm) radiation and penetration to the earth's surface of previously absorbed wavelengths below about 280 nm. The increased ultraviolet radiation would increase the likelihood of skin cancer in man and ocular squamous cell carcinoma in cattle. The climate also might be modified, possibly in an undesirable way. PMID:568617

  2. Capstone Depleted Uranium Aerosols: Generation and Characterization

    SciTech Connect

    Parkhurst, MaryAnn; Szrom, Fran; Guilmette, Ray; Holmes, Tom; Cheng, Yung-Sung; Kenoyer, Judson L.; Collins, John W.; Sanderson, T. Ellory; Fliszar, Richard W.; Gold, Kenneth; Beckman, John C.; Long, Julie

    2004-10-19

    In a study designed to provide an improved scientific basis for assessing possible health effects from inhaling depleted uranium (DU) aerosols, a series of DU penetrators was fired at an Abrams tank and a Bradley fighting vehicle. A robust sampling system was designed to collect aerosols in this difficult environment and continuously monitor the sampler flow rates. Aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. They were also analyzed for uranium oxide phases, particle morphology, and dissolution in vitro. The resulting data provide input useful in human health risk assessments.

  3. Scientific assessment of ozone depletion: 1991

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Over the past few years, there have been highly significant advances in the understanding of the impact of human activities on the Earth's stratospheric ozone layer and the influence of changes in chemical composition of the radiative balance of the climate system. Specifically, since the last international scientific review (1989), there have been five major advances: (1) global ozone decreases; (2) polar ozone; (3) ozone and industrial halocarbons; (4) ozone and climate relations; and (5) ozone depletion potentials (ODP's) and global warming potentials (GWP's). These topics and others are discussed.

  4. Depletion of the Outer Asteroid Belt

    NASA Technical Reports Server (NTRS)

    Liou, Jer-Chyi; Malhotra, Renu

    1997-01-01

    During the early history of the solar system, it is likely that the outer planets changed their distance from the sun, and hence, their influence on the asteroid belt evolved with time. The gravitational influence of Jupiter and Saturn on the orbital evolution of asteroids in the outer asteroid belt was calculated. The results show that the sweeping of mean motion resonances associated with planetary migration efficiently destabilizes orbits in the outer asteroid belt on a time scale of 10 million years. This mechanism provides an explanation for the observed depletion of asteroids in that region.

  5. Correlation between cosmic rays and ozone depletion.

    PubMed

    Lu, Q-B

    2009-03-20

    This Letter reports reliable satellite data in the period of 1980-2007 covering two full 11-yr cosmic ray (CR) cycles, clearly showing the correlation between CRs and ozone depletion, especially the polar ozone loss (hole) over Antarctica. The results provide strong evidence of the physical mechanism that the CR-driven electron-induced reaction of halogenated molecules plays the dominant role in causing the ozone hole. Moreover, this mechanism predicts one of the severest ozone losses in 2008-2009 and probably another large hole around 2019-2020, according to the 11-yr CR cycle. PMID:19392251

  6. Mesospheric ionization and O2 1Delta(g) depletion

    NASA Technical Reports Server (NTRS)

    Spear, K. A.; Solomon, S.

    1987-01-01

    Observations of O2 1Delta(g) emission during solar proton events reveal large depletions below 80 and near 90 km. The lower-altitude depletions are believed to be due to odd hydrogen production and associated depletion of ozone, but the mechanism producing the depletion near 90 km has not yet been established. In this paper, it is proposed that an exothermic charge exchange reaction between O2(+) and O2 1Delta(g) is likely to be responsible for these high-altitude depletions. In particular, it is shown that the vertical structure of the observed change in airglow emission is consistent with this mechanism.

  7. Star Formation in Partially Gas-Depleted Spiral Galaxies

    NASA Astrophysics Data System (ADS)

    Rose, James A.; Robertson, Paul; Miner, Jesse; Levy, Lorenza

    2010-02-01

    Broadband B and R and Hα images have been obtained with the 4.1 m SOAR telescope atop Cerro Pachon, Chile, for 29 spiral galaxies in the Pegasus I galaxy cluster and for 18 spirals in non-cluster environments. Pegasus I is a spiral-rich cluster with a low-density intracluster medium and a low galaxy velocity dispersion. When combined with neutral hydrogen (H I) data obtained with the Arecibo 305 m radio telescope, acquired by Levy et al. (2007) and by Springob et al. (2005b), we study the star formation rates in disk galaxies as a function of their H I deficiency. To quantify H I deficiency, we use the usual logarithmic deficiency parameter, DEF. The specific star formation rate (SSFR) is quantified by the logarithmic flux ratio of Hα flux to R-band flux, and thus roughly characterizes the logarithmic SFR per unit stellar mass. We find a clear correlation between the global SFR per unit stellar mass and DEF, such that the SFR is lower in more H I-deficient galaxies. This correlation appears to extend from the most gas-rich to the most gas-poor galaxies. We also find a correlation between the central SFR per unit mass relative to the global values, in the sense that the more H I-deficient galaxies have a higher central SFR per unit mass relative to their global SFR values than do gas-rich galaxies. In fact, approximately half of the H I-depleted galaxies have highly elevated SSFRs in their central regions, indicative of a transient evolutionary state. In addition, we find a correlation between gas depletion and the size of the Hα disk (relative to the R-band disk); H I-poor galaxies have truncated disks. Moreover, aside from the elevated central SSFR in many gas-poor spirals, the SSFR is otherwise lower in the Hα disks of gas-poor galaxies than in gas-rich spirals. Thus, both disk truncation and lowered SSFR levels within the star-forming part of the disks (aside from the enhanced nuclear SSFR) correlate with H I deficiency, and both phenomena are found to

  8. Martian meteorite Tissint records unique petrogenesis among the depleted shergottites

    NASA Astrophysics Data System (ADS)

    Basu Sarbadhikari, A.; Babu, E. V. S. S. K.; Vijaya Kumar, T.; Chennaoui Aoudjehane, H.

    2016-09-01

    Tissint, a new unaltered piece of Martian volcanic materials, is the most silica-poor and Mg-Fe-rich igneous rock among the "depleted" olivine-phyric shergottites. Fe-Mg zoning of olivine suggests equilibrium growth (<0.1 °C h-1) in the range of Fo80-56 and olivine overgrowth (Fo55-18) through a process of rapid disequilibrium (~1.0-5.0 °C h-1). The spatially extended (up to 600 μm) flat-top Fe-Mg profiles of olivine indicates that the early-stage cooling rate of Tissint was slower than the other shergottites. The chemically metastable outer rim of olivine (suppressing the plagioclase crystallization, which also caused a profound effect on the Al-content in the late-crystallized pyroxenes. Mineral chemical stability, phase-assemblage saturation, and pressure-temperature path of evolution indicates that the parent magma entered the solidus and left the liquidus field at a depth of 40-80 km in the upper mantle. Petrogenesis of Tissint appears to be similar to LAR 06319, an enriched olivine-phyric shergottite, during the early to intermediate stage of crystallization. A severe shock-induced deformation resulted in remelting (10-15 vol%), recrystallization (most Fe-rich phases), and exhumation of Tissint in a time scale of 1-8 yr. Tissint possesses some distinct characteristics, e.g., impact-induced melting and deformation, forming phosphorus-rich recrystallization rims of olivine, and shock-induced melt domains without relative enrichment of LREEs compared to the bulk; and shared characteristics, e.g., modal

  9. Martian meteorite Tissint records unique petrogenesis among the depleted shergottites

    NASA Astrophysics Data System (ADS)

    Basu Sarbadhikari, A.; Babu, E. V. S. S. K.; Vijaya Kumar, T.; Chennaoui Aoudjehane, H.

    2016-07-01

    Tissint, a new unaltered piece of Martian volcanic materials, is the most silica-poor and Mg-Fe-rich igneous rock among the "depleted" olivine-phyric shergottites. Fe-Mg zoning of olivine suggests equilibrium growth (<0.1 °C h-1) in the range of Fo80-56 and olivine overgrowth (Fo55-18) through a process of rapid disequilibrium (~1.0-5.0 °C h-1). The spatially extended (up to 600 μm) flat-top Fe-Mg profiles of olivine indicates that the early-stage cooling rate of Tissint was slower than the other shergottites. The chemically metastable outer rim of olivine (suppressing the plagioclase crystallization, which also caused a profound effect on the Al-content in the late-crystallized pyroxenes. Mineral chemical stability, phase-assemblage saturation, and pressure-temperature path of evolution indicates that the parent magma entered the solidus and left the liquidus field at a depth of 40-80 km in the upper mantle. Petrogenesis of Tissint appears to be similar to LAR 06319, an enriched olivine-phyric shergottite, during the early to intermediate stage of crystallization. A severe shock-induced deformation resulted in remelting (10-15 vol%), recrystallization (most Fe-rich phases), and exhumation of Tissint in a time scale of 1-8 yr. Tissint possesses some distinct characteristics, e.g., impact-induced melting and deformation, forming phosphorus-rich recrystallization rims of olivine, and shock-induced melt domains without relative enrichment of LREEs compared to the bulk; and shared characteristics, e.g., modal

  10. STAR FORMATION IN PARTIALLY GAS-DEPLETED SPIRAL GALAXIES

    SciTech Connect

    Rose, James A.; Miner, Jesse; Levy, Lorenza; Robertson, Paul E-mail: paul@astr.as.utexas.edu E-mail: lorenza.levy@yahoo.com

    2010-02-15

    Broadband B and R and H{alpha} images have been obtained with the 4.1 m SOAR telescope atop Cerro Pachon, Chile, for 29 spiral galaxies in the Pegasus I galaxy cluster and for 18 spirals in non-cluster environments. Pegasus I is a spiral-rich cluster with a low-density intracluster medium and a low galaxy velocity dispersion. When combined with neutral hydrogen (H I) data obtained with the Arecibo 305 m radio telescope, acquired by Levy et al. (2007) and by Springob et al. (2005b), we study the star formation rates in disk galaxies as a function of their H I deficiency. To quantify H I deficiency, we use the usual logarithmic deficiency parameter, DEF. The specific star formation rate (SSFR) is quantified by the logarithmic flux ratio of H{alpha} flux to R-band flux, and thus roughly characterizes the logarithmic SFR per unit stellar mass. We find a clear correlation between the global SFR per unit stellar mass and DEF, such that the SFR is lower in more H I-deficient galaxies. This correlation appears to extend from the most gas-rich to the most gas-poor galaxies. We also find a correlation between the central SFR per unit mass relative to the global values, in the sense that the more H I-deficient galaxies have a higher central SFR per unit mass relative to their global SFR values than do gas-rich galaxies. In fact, approximately half of the H I-depleted galaxies have highly elevated SSFRs in their central regions, indicative of a transient evolutionary state. In addition, we find a correlation between gas depletion and the size of the H{alpha} disk (relative to the R-band disk); H I-poor galaxies have truncated disks. Moreover, aside from the elevated central SSFR in many gas-poor spirals, the SSFR is otherwise lower in the H{alpha} disks of gas-poor galaxies than in gas-rich spirals. Thus, both disk truncation and lowered SSFR levels within the star-forming part of the disks (aside from the enhanced nuclear SSFR) correlate with H I deficiency, and both

  11. A critical comparison of ionospheric depletion chemicals

    SciTech Connect

    Bernhardt, P.A. )

    1987-05-01

    Six chemicals, H{sub 2}, H{sub 2}O, CO{sub 2}, SF{sub 6}, CF{sub 3}BR, and Ni(CO){sub 4}, are considered as ionospheric modification agents. Each of these species reacts in the F region to produce localized plasma depletions. The first three interact with O{sup +} and yield polyatomic ions which dissociatively recombine with electrons to give neutrals. The last three dissociatively attach electrons to produce heavy negative ions which become mutually neutralized by reactions with O{sup +}. The effectiveness of these chemicals depends on the amount which goes into the vapor state upon release. Thermodynamic calculations show that H{sub 2}O has the lowest vapor yield of about 20% from a heated, pressurized tank. Over 60% of the other substances should be vented in gaseous form. Based on estimates of plasma density reduction and airglow stimulation, nickel carbonyl is the most efficient of the six species for modifying the nighttime ionosphere. During the daytime, CF{sub 3}BR and SF{sub 6} provide the largest depletions.

  12. Convective Polymer Depletion on Pair Particle Interactions

    NASA Astrophysics Data System (ADS)

    Fan, Tai-Hsi; Taniguchi, Takashi; Tuinier, Remco

    2011-11-01

    Understanding transport, reaction, aggregation, and viscoelastic properties of colloid-polymer mixture is of great importance in food, biomedical, and pharmaceutical sciences. In non-adsorbing polymer solutions, colloidal particles tend to aggregate due to the depletion-induced osmotic or entropic force. Our early development for the relative mobility of pair particles assumed that polymer reorganization around the particles is much faster than particle's diffusive time, so that the coupling of diffusive and convective effects can be neglected. Here we present a nonequilibrium two-fluid (polymer and solvent) model to resolve the convective depletion effect. The theoretical framework is based on ground state approximation and accounts for the coupling of fluid flow and polymer transport to better describe pair particle interactions. The momentum and polymer transport, chemical potential, and local viscosity and osmotic pressure are simultaneously solved by numerical approximation. This investigation is essential for predicting the demixing kinetics in the pairwise regime for colloid-polymer mixtures. This work is supported by NSF CMMI 0952646.

  13. Stratospheric ozone depletion and animal health.

    PubMed

    Mayer, S J

    1992-08-01

    There is an increasing concern over ozone depletion and its effects on the environment and human health. However, the increase in ultraviolet-B radiation (UV-B) that would result from significant losses of ozone is also potentially harmful to animals. Any increase in disease in domestic species would not only have serious animal welfare implications but may also be economically important. The diseases which are likely to increase if ozone depletion continues include the squamous cell carcinomas of the exposed, non-pigmented areas of cats, cattle, sheep and horses. Uberreiter's syndrome in dogs is also associated with exposure to UV-B and may be expected to increase, as may the severity of conditions such as infectious keratoconjunctivitis (New Forest eye) in cattle. Aquaculture systems in which fish often have little or no protection by shading may also be at risk. Cataracts and skin lesions have been associated with the exposure of farmed fish to ultraviolet radiation and have resulted in significant losses. PMID:1529513

  14. Imaging neurotransmitter uptake and depletion in astrocytes

    SciTech Connect

    Tan, W. |; Haydon, P.G.; Yeung, E.S.

    1997-08-01

    An ultraviolet (UV) laser-based optical microscope and charge-coupled device (CCD) detection system was used to obtain chemical images of biological cells. Subcellular structures can be easily seen in both optical and fluorescence images. Laser-induced native fluorescence detection provides high sensitivity and low limits of detection, and it does not require coupling to fluorescent dyes. We were able to quantitatively monitor serotonin that has been taken up into and released from individual astrocytes on the basis of its native fluorescence. Different regions of the cells took up different amounts of serotonin with a variety of uptake kinetics. Similarly, we observed different serotonin depletion dynamics in different astrocyte regions. There were also some astrocyte areas where no serotonin uptake or depletion was observed. Potential applications include the mapping of other biogenic species in cells as well as the ability to image their release from specific regions of cells in response to external stimuli. {copyright} {ital 1997} {ital Society for Applied Spectroscopy}

  15. Halocarbon ozone depletion and global warming potentials

    NASA Technical Reports Server (NTRS)

    Cox, Richard A.; Wuebbles, D.; Atkinson, R.; Connell, Peter S.; Dorn, H. P.; Derudder, A.; Derwent, Richard G.; Fehsenfeld, F. C.; Fisher, D.; Isaksen, Ivar S. A.

    1990-01-01

    Concern over the global environmental consequences of fully halogenated chlorofluorocarbons (CFCs) has created a need to determine the potential impacts of other halogenated organic compounds on stratospheric ozone and climate. The CFCs, which do not contain an H atom, are not oxidized or photolyzed in the troposphere. These compounds are transported into the stratosphere where they decompose and can lead to chlorine catalyzed ozone depletion. The hydrochlorofluorocarbons (HCFCs or HFCs), in particular those proposed as substitutes for CFCs, contain at least one hydrogen atom in the molecule, which confers on these compounds a much greater sensitivity toward oxidation by hydroxyl radicals in the troposphere, resulting in much shorter atmospheric lifetimes than CFCs, and consequently lower potential for depleting ozone. The available information is reviewed which relates to the lifetime of these compounds (HCFCs and HFCs) in the troposphere, and up-to-date assessments are reported of the potential relative effects of CFCs, HCFCs, HFCs, and halons on stratospheric ozone and global climate (through 'greenhouse' global warming).

  16. A critical comparison of ionospheric depletion chemicals

    NASA Astrophysics Data System (ADS)

    Bernhardt, P. A.

    1987-05-01

    Six chemicals, H2, H2O, CO2, SF6, CF3Br, and Ni(CO)4, are considered as ionospheric modification agents. Each of these species reacts in the F region to produce localized plasma depletions. The first three interact with O(+) and yield polyatomic ions which dissociatively recombine with electrons to give neutrals. The last three dissociatively attach electrons to produce heavy negative ions which become mutually neutralized by reactions with O(+). The effectiveness of these chemicals depends on the amount which goes into the vapor state upon release. Thermodynamic calculations show that H2O has the lowest vapor yield of about 20 percent from a heated, pressurized tank. Over 60 percent of the other substances should be vented in gaseous form. Based on estimates of plasma density reduction and airglow stimulation, nickel carbonyl is the most efficient of the six species for modifying the nighttime ionosphere. During the daytime, CF3Br and SF6 provide the largest depletions.

  17. Next generation fire suppressants

    SciTech Connect

    Brown, J.A.

    1995-03-01

    Spectrex, Inc., located in Cedar Grove, NJ is a manufacturer of fire detection and suppression equipment. Spectrex is one of the original pioneers in high speed fire detection and suppression systems for combat vehicles. Spectrex has installed fire suppressions systems in thousands of combat vehicles and ships throughout the world. Additionally, they manufacture flame explosion detectors, ship damage control systems, and optical gas and vapor detectors. The culmination of several years of research and development has recently produced an innovative electro-optical continuous monitoring systems called SharpEye 20/20I IR(sup 3) and SAFEYE that provide fast and reliable gas, vapor, aerosol, flame, and explosion detection. SharpEye 20/20I IR(sup 3) is a self-contained triple spectrum flame detector which scans for oscillating IR radiation (1 to 10 Hz) in the spectral bands ranging from 4.0 to 5.0 microns and uses programmed algorithms to check the ratio and correlation of data received by the three sensors to make the system highly immune to false alarms. It is extremely sensitive as it can detect a 1 x 1 square foot gasoline pan fire at 200 feet in less than 3 seconds. The sensitivity is user programmable, offering 4 ranges of detection. SAFEYE is comprised of a selected number of multispectral band microprocessor controlled detectors which are in communication with one or more radiation sources that is projected along a 600 feet optical path. The signals from the selected narrow bands are processed and analyzed by highly sophisticated algorithms. It is ideal for high risk, remote, large areas such as petroleum and chemical manufacturing sites, waste dumps, aircraft cargo bays, and ship compartments. The SAFEYE will perform direct readings of the presence or rate of rise of concentrations of gases, vapors, or aerosols at the range of parts per million and provide alarms at various set points at different levels of concentrations.

  18. Next generation fire suppressants

    NASA Technical Reports Server (NTRS)

    Brown, Jerry A.

    1995-01-01

    Spectrex, Inc., located in Cedar Grove, NJ is a manufacturer of fire detection and suppression equipment. Spectrex is one of the original pioneers in high speed fire detection and suppression systems for combat vehicles. Spectrex has installed fire suppressions systems in thousands of combat vehicles and ships throughout the world. Additionally, they manufacture flame explosion detectors, ship damage control systems, and optical gas and vapor detectors. The culmination of several years of research and development has recently produced an innovative electro-optical continuous monitoring systems called SharpEye 20/20I IR(sup 3) and SAFEYE that provide fast and reliable gas, vapor, aerosol, flame, and explosion detection. SharpEye 20/20I IR(sup 3) is a self-contained triple spectrum flame detector which scans for oscillating IR radiation (1 to 10 Hz) in the spectral bands ranging from 4.0 to 5.0 microns and uses programmed algorithms to check the ratio and correlation of data received by the three sensors to make the system highly immune to false alarms. It is extremely sensitive as it can detect a 1 x 1 square foot gasoline pan fire at 200 feet in less than 3 seconds. The sensitivity is user programmable, offering 4 ranges of detection. SAFEYE is comprised of a selected number of multispectral ban microprocessors controlled detectors which are in communication with one or more radiation sources that is projected along a 600 feet optical path. The signals from the selected narrow bands are processed and analyzed by highly sophisticated algorithms. It is ideal for high risk, remote, large areas such as petroleum and chemical manufacturing sites, waste dumps, aircraft cargo bays, and ship compartments. The SAFEYE will perform direct readings of the presence or rate of rise of concentrations of gases, vapors, or aerosols at the range of parts per million and provide alarms at various set points at different levels of concentrations.

  19. Suppression of flutter

    NASA Technical Reports Server (NTRS)

    Nissim, E. (Inventor)

    1973-01-01

    An active aerodynamic control system to control flutter over a large range of oscillatory frequencies is described. The system is not affected by mass, stiffness, elastic axis, or center of gravity location of the system, mode of vibration, or Mach number. The system consists of one or more pairs of leading edge and trailing edge hinged or deformable control surfaces, each pair operated in concert by a stability augmentation system. Torsion and bending motions are sensed and converted by the stability augmentation system into leading and trailing edge control surface deflections which produce lift forces and pitching moments to suppress flutter.

  20. Microfabrics in depleted mantle plaeotransform (New Caledonia)

    NASA Astrophysics Data System (ADS)

    Teyssier, Christian; Chatzaras, Vasileios; Von Der Handt, Anette

    2016-04-01

    The New Caledonia ophiolite contains several wrench zones that have been interpreted as paleotransforms. These transform-ridge systems developed at the transition between ridge development and intra-oceanic subduction that resulted in depleted mantle (about 18 % melt according to olivine Mg# - spinel Cr#). The most prominent is the Bogota Peninsula paleotransform, a 10 km wide shear zone in which strain localizes in the 2 km wide Ouassé mylonite zone. This strain gradient is associated with microstructure and microfabric evolution that informs the relationship between hydration and strain in mantle mylonite. Olivine recrystallized grain size varies from about 1 mm to about 0.2 mm toward the mylonite zone. The strain gradient is also demonstrated by increasing deformation of orthopyroxene (opx) grains that become elongate porphyroclasts in the mylonite zone. Orthopyroxene geothermometry reveals T ~ 1050-1000 C (Ca-opx) and 950-850 C (Cr-Al-opx) in the least deformed rocks. In the mylonite zone a wider range of T is recorded, with minima reaching 850 C (Ca-opx) and 750 C (Cr-Al-opx). Electron microprobe analysis also detects the presence of 20-200 micron interstitial, high-temperature amphibole (pargasite), with modal abundance increasing in the mylonite zone; this suggests that high-temperature pervasive fluid flow may have played a role in strain localization and mylonitization. Olivine crystallographic fabrics include A-type and E-type, the latter possibly reflecting hydration of shear zone tectonites. E-type fabrics are present in both mylonite and less deformed rocks, and appear to be more common in rocks with olivine grain size < 400 microns. A correlation between E-type fabrics and amphibole mode is being investigated. The shear zone protolith was depleted mantle in which the ridge-transform system was permeated by fluids. These fluids initially originated at the subduction interface, but during the transform evolution, ocean water likely permeated the shear

  1. Dietary Methyl Donor Depletion Protects Against Intestinal Tumorigenesis in ApcMin/+ Mice

    PubMed Central

    Kadaveru, Krishna; Protiva, Petr; Greenspan, Emily J; Kim, Young-In; Rosenberg, Daniel W

    2012-01-01

    Despite recent population data, the influence of dietary folate supplementation on colon cancer risk remains controversial. This study examines the effects of folate deficiency, in combination with choline, methionine and vitamin B12 depletion, on intestinal tumorigenesis in ApcMin/+ mice. Methyl donor sufficient (MDS) and deficient (MDD) diets were started at 5 or 10 weeks of age and tumors evaluated at 16 weeks. MDD suppressed intestinal tumor formation in ApcMin/+ mice (~80%) when started at 5 weeks of age. The protective effect was lost when MDD was initiated at 10 weeks of age, indicating an important time-dependency on cancer suppression. Concomitant with cancer protection, MDD restricted body weight gain. Therefore, a second study was conducted in which MDS was given ad libitum or pair-fed with MDD. While small intestinal tumors were reduced 54% in pair-fed MDS mice, MDD caused a further reduction (96%). In colon, although MDD did not affect tumor numbers, tumor size was reduced. Gene expression profiling of normal-appearing colonic mucosa after 11 weeks on MDD identified a total of 493 significantly down-regulated genes relative to the MDS group. Pathway analysis placed many of these genes within general categories of inflammatory signaling and cell cycle regulation, consistent with recently published human data obtained during folate depletion (1). Further studies are warranted to investigate the complex interplay of methyl donor status and cancer protection in high-risk populations. PMID:22677908

  2. Depletion of calcium stores regulates calcium influx and signal transmission in rod photoreceptors

    PubMed Central

    Szikra, Tamas; Cusato, Karen; Thoreson, Wallace B; Barabas, Peter; Bartoletti, Theodore M; Krizaj, David

    2008-01-01

    Tonic synapses are specialized for sustained calcium entry and transmitter release, allowing them to operate in a graded fashion over a wide dynamic range. We identified a novel plasma membrane calcium entry mechanism that extends the range of rod photoreceptor signalling into light-adapted conditions. The mechanism, which shares molecular and physiological characteristics with store-operated calcium entry (SOCE), is required to maintain baseline [Ca2+]i in rod inner segments and synaptic terminals. Sustained Ca2+ entry into rod cytosol is augmented by store depletion, blocked by La3+ and Gd3+ and suppressed by organic antagonists MRS-1845 and SKF-96365. Store depletion and the subsequent Ca2+ influx directly stimulated exocytosis in terminals of light-adapted rods loaded with the activity-dependent dye FM1–43. Moreover, SOCE blockers suppressed rod-mediated synaptic inputs to horizontal cells without affecting presynaptic voltage-operated Ca2+ entry. Silencing of TRPC1 expression with small interference RNA disrupted SOCE in rods, but had no effect on cone Ca2+ signalling. Rods were immunopositive for TRPC1 whereas cone inner segments immunostained with TRPC6 channel antibodies. Thus, SOCE modulates Ca2+ homeostasis and light-evoked neurotransmission at the rod photoreceptor synapse mediated by TRPC1. PMID:18755743

  3. The confinement of star-forming galaxies into a main sequence through episodes of gas compaction, depletion and replenishment

    NASA Astrophysics Data System (ADS)

    Tacchella, Sandro; Dekel, Avishai; Carollo, C. Marcella; Ceverino, Daniel; DeGraf, Colin; Lapiner, Sharon; Mandelker, Nir; Primack Joel, R.

    2016-04-01

    Using cosmological simulations, we address the properties of high-redshift star-forming galaxies (SFGs) across their main sequence (MS) in the plane of star formation rate (SFR) versus stellar mass. We relate them to the evolution of galaxies through phases of gas compaction, depletion, possible replenishment, and eventual quenching. We find that the high-SFR galaxies in the upper envelope of the MS are compact, with high gas fractions and short depletion times (`blue nuggets'), while the lower SFR galaxies in the lower envelope have lower central gas densities, lower gas fractions, and longer depletion times, consistent with observed gradients across the MS. Stellar-structure gradients are negligible. The SFGs oscillate about the MS ridge on time-scales ˜0.4tHubble (˜1 Gyr at z ˜ 3). The propagation upwards is due to gas compaction, triggered, e.g. by mergers, counter-rotating streams, and/or violent disc instabilities. The downturn at the upper envelope is due to central gas depletion by peak star formation and outflows while inflow from the shrunken gas disc is suppressed. An upturn at the lower envelope can occur once the extended disc has been replenished by fresh gas and a new compaction can be triggered, namely as long as the replenishment time is shorter than the depletion time. The mechanisms of gas compaction, depletion, and replenishment confine the SFGs to the narrow (±0.3 dex) MS. Full quenching occurs in massive haloes (Mvir > 1011.5 M⊙) and/or at low redshifts (z < 3), where the replenishment time is long compared to the depletion time, explaining the observed bending down of the MS at the massive end.

  4. Acute dyskerin depletion triggers cellular senescence and renders osteosarcoma cells resistant to genotoxic stress-induced apoptosis

    SciTech Connect

    Lin, Ping; Mobasher, Maral E.; Alawi, Faizan

    2014-04-18

    Highlights: • Dyskerin depletion triggers cellular senescence in U2OS osteosarcoma cells. • Dyskerin-depleted cells are resistant to apoptosis induced by genotoxic stress. • Chromatin relaxation sensitizes dyskerin-depleted cells to apoptosis. - Abstract: Dyskerin is a conserved, nucleolar RNA-binding protein implicated in an increasing array of fundamental cellular processes. Germline mutation in the dyskerin gene (DKC1) is the cause of X-linked dyskeratosis congenita (DC). Conversely, wild-type dyskerin is overexpressed in sporadic cancers, and high-levels may be associated with poor prognosis. It was previously reported that acute loss of dyskerin function via siRNA-mediated depletion slowed the proliferation of transformed cell lines. However, the mechanisms remained unclear. Using human U2OS osteosarcoma cells, we show that siRNA-mediated dyskerin depletion induced cellular senescence as evidenced by proliferative arrest, senescence-associated heterochromatinization and a senescence-associated molecular profile. Senescence can render cells resistant to apoptosis. Conversely, chromatin relaxation can reverse the repressive effects of senescence-associated heterochromatinization on apoptosis. To this end, genotoxic stress-induced apoptosis was suppressed in dyskerin-depleted cells. In contrast, agents that induce chromatin relaxation, including histone deacetylase inhibitors and the DNA intercalator chloroquine, sensitized dyskerin-depleted cells to apoptosis. Dyskerin is a core component of the telomerase complex and plays an important role in telomere homeostasis. Defective telomere maintenance resulting in premature senescence is thought to primarily underlie the pathogenesis of X-linked DC. Since U2OS cells are telomerase-negative, this leads us to conclude that loss of dyskerin function can also induce cellular senescence via mechanisms independent of telomere shortening.

  5. Planck-suppressed operators

    SciTech Connect

    Assassi, Valentin; Baumann, Daniel; Green, Daniel; McAllister, Liam E-mail: dbaumann@damtp.cam.ac.uk E-mail: mcallister@cornell.edu

    2014-01-01

    We show that the recent Planck limits on primordial non-Gaussianity impose strong constraints on light hidden sector fields coupled to the inflaton via operators suppressed by a high mass scale Λ. We study a simple effective field theory in which a hidden sector field is coupled to a shift-symmetric inflaton via arbitrary operators up to dimension five. Self-interactions in the hidden sector lead to non-Gaussianity in the curvature perturbations. To be consistent with the Planck limit on local non-Gaussianity, the coupling to any hidden sector with light fields and natural cubic couplings must be suppressed by a very high scale Λ > 10{sup 5}H. Even if the hidden sector has Gaussian correlations, nonlinearities in the mixing with the inflaton still lead to non-Gaussian curvature perturbations. In this case, the non-Gaussianity is of the equilateral or orthogonal type, and the Planck data requires Λ > 10{sup 2}H.

  6. ARTD1/PARP1 negatively regulates glycolysis by inhibiting hexokinase 1 independent of NAD+ depletion

    PubMed Central

    Fouquerel, Elise; Goellner, Eva M.; Yu, Zhongxun; Gagné, Jean-Philippe; de Moura, Michelle Barbi; Feinstein, Tim; Wheeler, David; Redpath, Philip; Li, Jianfeng; Romero, Guillermo; Migaud, Marie; Van Houten, Bennett; Poirier, Guy G.; Sobol, Robert W.

    2014-01-01

    Summary ARTD1 (PARP1) is a key enzyme involved in DNA repair by synthesizing poly(ADP-ribose) (PAR) in response to strand breaks and plays an important role in cell death following excessive DNA damage. ARTD1-induced cell death is associated with NAD+ depletion and ATP loss, however the molecular mechanism of ARTD1-mediated energy collapse remains elusive. Using real-time metabolic measurements, we directly compared the effects of ARTD1 activation and direct NAD+ depletion. We found that ARTD1-mediated PAR synthesis, but not direct NAD+ depletion, resulted in a block to glycolysis and ATP loss. We then established a proteomics based PAR-interactome after DNA damage and identified hexokinase 1 (HK1) as a PAR binding protein. HK1 activity is suppressed following nuclear ARTD1 activation and binding by PAR. These findings help explain how prolonged activation of ARTD1 triggers energy collapse and cell death, revealing new insight on the importance of nucleus to mitochondria communication via ARTD1 activation. PMID:25220464

  7. Vacancy Formation Enthalpy in Polycrystalline Depleted Uranium

    NASA Astrophysics Data System (ADS)

    Lund, K. R.; Lynn, K. G.; Weber, M. H.; Okuniewski, M. A.

    2013-06-01

    Positron Annihilation Spectroscopy was performed as a function of temperature and beam energy on polycrystalline depleted uranium (DU) foil. Samples were run with varying heat profiles all starting at room temperature. While collecting Doppler-Broadening data, the temperature of the sample was cycled several times. The first heat cycle shows an increasing S-parameter near temperatures of 400K to 500K much lower than the first phase transition of 941K indicating increasing vacancies possibly due to oxygen diffusion from the bulk to the surface. Vacancy formation enthalpies were calculated fitting a model to the data to be 1.6± 0.16 eV. Results are compared to previous work [3,4].

  8. Health effects of embedded depleted uranium.

    PubMed

    McClain, David E; Benson, Kimberly A; Dalton, Tom K; Ejnik, John; Emond, Christy A; Hodge, Shelly J; Kalinich, John F; Landauer, Michael R; Livengood, David R; Miller, Alexandra C; Pellmar, Terry C; Stewart, Michael D; Villa, Vilmar; Xu, Jiaquan

    2002-02-01

    The health effects of embedded fragments of depleted uranium (DU) are being investigated to determine whether current surgical fragment-removal policies are appropriate for this metal. The authors studied rodents implanted with DU pellets as well as cultured human cells exposed to DU compounds. Results indicate that uranium from implanted DU fragments distributes to tissues distant from implantation sites, including bone, kidney, muscle, and liver. Despite levels of uranium in kidney that would be nephrotoxic after acute exposure, no histological or functional kidney toxicity was observed with embedded DU, indicating that the kidney adapts when exposed chronically. Nonetheless, further studies of the long-term health impact are needed. DU is mutagenic and transforms human osteoblastic cells into a tumorigenic phenotype. It alters neurophysiological parameters in rat hippocampus, crosses the placental barrier, and enters fetal tissue. Preliminary data also indicate decreased rodent litter size when animals are bred 6 months or longer after DU implantation. PMID:11873491

  9. Tylosin depletion from edible pig tissues.

    PubMed

    Prats, C; El Korchi, G; Francesch, R; Arboix, M; Pérez, B

    2002-12-01

    The depletion of tylosin from edible pig tissues was studied following 5 days of intramuscular (i.m.) administration of 10 mg/kg of tylosin to 16 crossbreed pigs. Animals were slaughtered at intervals after treatment and samples of muscle, kidney, liver, skin+fat, and injection site were collected and analysed by high-performance liquid chromatography (HPLC). Seven days after the completion of treatment, the concentration of tylosin in kidney, skin+fat, and at the injection site was higher than the European Union maximal residue limit (MRL) of 100 microg/kg. Tylosin residues in all tissues were below the quantification limit (50 microg/kg) at 10 and 14 days post-treatment. PMID:12443694

  10. Policies on global warming and ozone depletion

    SciTech Connect

    Green, B.

    1987-04-01

    The recent discovery of a dramatic seasonal drop in the amount of ozone over Antarctica has catalyzed concern for protection of stratospheric ozone, the layer of gas that shields the entire planet from excess ultraviolet radiation. Conservative scientific models predict about a 5% reduction in the amount of global ozone by the middle of the next century, with large local variations. The predicted global warming from increased emissions of greenhouse gases will also have differing effects on local climate and weather conditions and consequently on agriculture. Although numerous uncertainties are associated with both ozone depletion and a global warming, there is a consensus that world leaders need to address the problems. The US Congress is now beginning to take note of the task. In this article, one representative outlines some perceptions of the problems and the policy options available to Congress.

  11. Arctic Ozone Depletion from UARS MLS Measurements

    NASA Technical Reports Server (NTRS)

    Manney, G. L.

    1995-01-01

    Microwave Limb Sounder (MLS) measurements of ozone during four Arctic winters are compared. The evolution of ozone in the lower stratosphere is related to temperature, chlorine monoxide (also measured by MLS), and the evolution of the polar vortex. Lagrangian transport calculations using winds from the United Kingdom Meteorological Office's Stratosphere-Troposphere Data Assimilation system are used to estimate to what extent the evolution of lower stratospheric ozone is controlled by dynamics. Observations, along with calculations of the expected dynamical behavior, show evidence for chemical ozone depletion throughout most of the Arctic lower stratospheric vortex during the 1992-93 middle and late winter, and during all of the 1994-95 winter that was observed by MLS. Both of these winters were unusually cold and had unusually cold and had unusually strong Arctic polar vortices compared to meteorological data over the past 17 years.

  12. Modelling chemical depletion profiles in regolith

    USGS Publications Warehouse

    Brantley, S.L.; Bandstra, J.; Moore, J.; White, A.F.

    2008-01-01

    Chemical or mineralogical profiles in regolith display reaction fronts that document depletion of leachable elements or minerals. A generalized equation employing lumped parameters was derived to model such ubiquitously observed patterns:C = frac(C0, frac(C0 - Cx = 0, Cx = 0) exp (??ini ?? over(k, ??) ?? x) + 1)Here C, Cx = 0, and Co are the concentrations of an element at a given depth x, at the top of the reaction front, or in parent respectively. ??ini is the roughness of the dissolving mineral in the parent and k???? is a lumped kinetic parameter. This kinetic parameter is an inverse function of the porefluid advective velocity and a direct function of the dissolution rate constant times mineral surface area per unit volume regolith. This model equation fits profiles of concentration versus depth for albite in seven weathering systems and is consistent with the interpretation that the surface area (m2 mineral m- 3 bulk regolith) varies linearly with the concentration of the dissolving mineral across the front. Dissolution rate constants can be calculated from the lumped fit parameters for these profiles using observed values of weathering advance rate, the proton driving force, the geometric surface area per unit volume regolith and parent concentration of albite. These calculated values of the dissolution rate constant compare favorably to literature values. The model equation, useful for reaction fronts in both steady-state erosional and quasi-stationary non-erosional systems, incorporates the variation of reaction affinity using pH as a master variable. Use of this model equation to fit depletion fronts for soils highlights the importance of buffering of pH in the soil system. Furthermore, the equation should allow better understanding of the effects of important environmental variables on weathering rates. ?? 2008.

  13. FOXO1/3 and PTEN Depletion in Granulosa Cells Promotes Ovarian Granulosa Cell Tumor Development.

    PubMed

    Liu, Zhilin; Ren, Yi A; Pangas, Stephanie A; Adams, Jaye; Zhou, Wei; Castrillon, Diego H; Wilhelm, Dagmar; Richards, JoAnne S

    2015-07-01

    The forkhead box (FOX), FOXO1 and FOXO3, transcription factors regulate multiple functions in mammalian cells. Selective inactivation of the Foxo1 and Foxo3 genes in murine ovarian granulosa cells severely impairs follicular development and apoptosis causing infertility, and as shown here, granulosa cell tumor (GCT) formation. Coordinate depletion of the tumor suppressor Pten gene in the Foxo1/3 strain enhanced the penetrance and onset of GCT formation. Immunostaining and Western blot analyses confirmed FOXO1 and phosphatase and tensin homolog (PTEN) depletion, maintenance of globin transcription factor (GATA) 4 and nuclear localization of FOXL2 and phosphorylated small mothers against decapentaplegic (SMAD) 2/3 in the tumor cells, recapitulating results we observed in human adult GCTs. Microarray and quantitative PCR analyses of mouse GCTs further confirmed expression of specific genes (Foxl2, Gata4, and Wnt4) controlling granulosa cell fate specification and proliferation, whereas others (Emx2, Nr0b1, Rspo1, and Wt1) were suppressed. Key genes (Amh, Bmp2, and Fshr) controlling follicle growth, apoptosis, and differentiation were also suppressed. Inhbb and Grem1 were selectively elevated, whereas reduction of Inha provided additional evidence that activin signaling and small mothers against decapentaplegic (SMAD) 2/3 phosphorylation impact GCT formation. Unexpectedly, markers of Sertoli/epithelial cells (SRY [sex determining region Y]-box 9/keratin 8) and alternatively activated macrophages (chitinase 3-like 3) were elevated in discrete subpopulations within the mouse GCTs, indicating that Foxo1/3/Pten depletion not only leads to GCTs but also to altered granulosa cell fate decisions and immune responses. Thus, analyses of the Foxo1/3/Pten mouse GCTs and human adult GCTs provide strong evidence that impaired functions of the FOXO1/3/PTEN pathways lead to dramatic changes in the molecular program within granulosa cells, chronic activin signaling in the presence of

  14. Using depletion to control colloidal crystal assemblies of hard cuboctahedra.

    PubMed

    Karas, Andrew S; Glaser, Jens; Glotzer, Sharon C

    2016-06-21

    Depletion interactions arise from entropic forces, and their ability to induce aggregation and even ordering of colloidal particles through self-assembly is well established, especially for spherical colloids. We vary the size and concentration of penetrable hard sphere depletants in a system of cuboctahedra, and we show how depletion changes the preferential facet alignment of the colloids and thereby selects different crystal structures. Moreover, we explain the cuboctahedra phase behavior using perturbative free energy calculations. We find that cuboctahedra can form a stable simple cubic phase, and, remarkably, that the stability of this phase can be rationalized only by considering the effects of both the colloid and depletant entropy. We corroborate our results by analyzing how the depletant concentration and size affect the emergent directional entropic forces and hence the effective particle shape. We propose the use of depletants as a means of easily changing the effective shape of self-assembling anisotropic colloids. PMID:27194463

  15. Factors influencing dust suppressant effectiveness

    SciTech Connect

    Copeland, C.R.; Eisele, T.C.; Chesney, D.J.; Kawatra, S.K.

    2008-11-15

    Water sprays are a common method used to reduce particulate matter (PM) emissions. Various factors such as wettability, surface area coverage, fine particle engulfment rates, interparticle adhesion forces, suppressant penetration and suppressant longevity have all been suggested as critical factors in achieving effective PM control. However, it has not been established which of these factors are the most important. Experimental work indicated that suppressant penetration is the most critical of these factors. The length of time after application that suppressants were effective was also improved by using hygroscopic reagents that retained moisture to prevent evaporation. Maximizing suppressant penetration and improving suppressant longevity led to an average 86% reduction in PM10 concentrations in laboratory dust tower tests.

  16. ZERO SUPPRESSION FOR RECORDERS

    DOEpatents

    Fort, W.G.S.

    1958-12-30

    A zero-suppression circuit for self-balancing recorder instruments is presented. The essential elements of the circuit include a converter-amplifier having two inputs, one for a reference voltage and the other for the signal voltage under analysis, and a servomotor with two control windings, one coupled to the a-c output of the converter-amplifier and the other receiving a reference input. Each input circuit to the converter-amplifier has a variable potentiometer and the sliders of the potentiometer are ganged together for movement by the servoinotor. The particular noveity of the circuit resides in the selection of resistance values for the potentiometer and a resistor in series with the potentiometer of the signal circuit to ensure the full value of signal voltage variation is impressed on a recorder mechanism driven by servomotor.

  17. Interference suppression of SRS

    SciTech Connect

    Kochanov, V P

    2011-01-24

    The theory of three-wave SRS is developed, which takes into account nonlinear dispersion of a medium for arbitrary phases of the pump waves at the input to the medium. The effect of interference suppression of SRS is predicted for values of the total phase of the three-wave pump (2n+1){pi} (n=0, {+-}1, {+-}2...), the effect being caused by the destructive interference of polarisations of the nonresonant dipole-allowed transitions. The relation between the contributions of the linear and nonlinear dispersions to the SRS is found. It is shown that at a sufficiently large wave detuning, the anti-Stokes wave amplitude experiences spatial oscillations. (nonlinear-optics phenomena)

  18. Pressure suppression system

    DOEpatents

    Gluntz, Douglas M.

    1994-01-01

    A pressure suppression system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and an enclosed gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The GDCS pool includes a plenum for receiving through an inlet the non-condensable gas carried with steam from the drywell following a loss-of-coolant accident (LOCA). A condenser is disposed in the GDCS plenum for condensing the steam channeled therein and to trap the non-condensable gas therein. A method of operation includes draining the GDCS pool following the LOCA and channeling steam released into the drywell following the LOCA into the GDCS plenum for cooling along with the non-condensable gas carried therewith for trapping the gas therein.

  19. Pressure suppression system

    DOEpatents

    Gluntz, D.M.

    1994-10-04

    A pressure suppression system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and an enclosed gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The GDCS pool includes a plenum for receiving through an inlet the non-condensable gas carried with steam from the drywell following a loss-of-coolant accident (LOCA). A condenser is disposed in the GDCS plenum for condensing the steam channeled therein and to trap the non-condensable gas therein. A method of operation includes draining the GDCS pool following the LOCA and channeling steam released into the drywell following the LOCA into the GDCS plenum for cooling along with the non-condensable gas carried therewith for trapping the gas therein. 3 figs.

  20. Virulent Salmonella typhimurium-induced lymphocyte depletion and immunosuppression in chickens.

    PubMed Central

    Hassan, J O; Curtiss, R

    1994-01-01

    The effect of experimental Salmonella infection on chicken lymphoid organs, immune responses, and fecal shedding of salmonellae were assessed following oral inoculation of 1-day-old chicks or intra-air-sac infection of 4-week-old chickens with virulent S. typhimurium wild-type chi 3761 or avirulent S. typhimurium delta cya delta crp vaccine strain chi 3985. Some 4-week-old chickens infected intra-air-sac with chi 3761 or chi 3985 were challenged with Bordetella avium to determine the effect of Salmonella infection on secondary infection by B. avium. S. typhimurium chi 3761 caused lymphocyte depletion, atrophy of lymphoid organs, and immunosuppression 2 days after infection in 1-day-old chicks and 4-week-old chickens. The observed lymphocyte depletion or atrophy of lymphoid organs was transient and dose dependent. Lymphocyte depletion and immunosuppression were associated with prolonged fecal shedding of S. typhimurium chi 3761. No lymphocyte depletion, immunosuppression, or prolonged Salmonella shedding was observed in groups of chickens infected orally or intra-air-sac with chi 3985. Infection of chickens with salmonellae before challenge with B. avium did not suppress the specific antibody response to B. avium. However, B. avium isolation was higher in visceral organs of chickens infected with chi 3761 and challenged with B. avium than in chickens infected with B. avium only. Infection of chickens with chi 3985 reduced B. avium colonization. We report a new factor in Salmonella pathogenesis and reveal a phenomenon which may play a critical role in the development of Salmonella carrier status in chickens. We also showed that 10(8) CFU of chi 3985, which is our established oral vaccination dose for chickens, did not cause immunosuppression or enhance the development of Salmonella carrier status in chickens. Images PMID:8168969

  1. Elemental Depletions in the Magellanic Clouds and the Evolution of Depletions with Metallicity

    NASA Astrophysics Data System (ADS)

    Tchernyshyov, Kirill; Meixner, Margaret; Seale, Jonathan; Fox, Andrew; Friedman, Scott D.; Dwek, Eli; Galliano, Frédéric

    2015-10-01

    We present a study of the composition of gas and dust in the Large and Small Magellanic Clouds (LMC and SMC) using UV absorption spectroscopy. We measure P ii and Fe ii along 84 spatially distributed sightlines toward the MCs using archival Far Ultraviolet Spectroscopic Explorer observations. For 16 of those sightlines, we also measure Si ii, Cr ii, and Zn ii from new Hubble Space Telescope Cosmic Origins Spectrograph observations. We analyze these spectra using a new spectral line analysis technique based on a semi-parametric Voigt profile model. We have combined these measurements with H i and H2 column densities and reference stellar abundances from the literature to derive gas-phase abundances, depletions, and gas-to-dust ratios (GDRs). Of our 84 P and 16 Zn measurements, 80 and 13, respectively, are depleted by more than 0.1 dex, suggesting that P and Zn abundances are not accurate metallicity indicators at and above the metallicity of the SMC. Si, Cr, and Fe are systematically less depleted in the SMC than in the Milky Way (MW) or LMC. The minimum Si depletion in the SMC is consistent with zero. We find GDR ranges of 190-565 in the LMC and 480-2100 in the SMC, which is broadly consistent with GDRs from the literature. These ranges represent actual location to location variation and are evidence of dust destruction and/or growth in the diffuse neutral phase of the interstellar medium. Where they overlap in metallicity, the gas-phase abundances of the MW, LMC, and SMC and damped Lyα systems evolve similarly with metallicity.

  2. Regret causes ego-depletion and finding benefits in the regrettable events alleviates ego-depletion.

    PubMed

    Gao, Hongmei; Zhang, Yan; Wang, Fang; Xu, Yan; Hong, Ying-Yi; Jiang, Jiang

    2014-01-01

    This study tested the hypotheses that experiencing regret would result in ego-depletion, while finding benefits (i.e., "silver linings") in the regret-eliciting events counteracted the ego-depletion effect. Using a modified gambling paradigm (Experiments 1, 2, and 4) and a retrospective method (Experiments 3 and 5), five experiments were conducted to induce regret. Results revealed that experiencing regret undermined performance on subsequent tasks, including a paper-and-pencil calculation task (Experiment 1), a Stroop task (Experiment 2), and a mental arithmetic task (Experiment 3). Furthermore, finding benefits in the regret-eliciting events improved subsequent performance (Experiments 4 and 5), and this improvement was mediated by participants' perceived vitality (Experiment 4). This study extended the depletion model of self-regulation by considering emotions with self-conscious components (in our case, regret). Moreover, it provided a comprehensive understanding of how people felt and performed after experiencing regret and after finding benefits in the events that caused the regret. PMID:24940811

  3. Dissociable saccadic suppression of pupillary and perceptual responses to light.

    PubMed

    Benedetto, Alessandro; Binda, Paola

    2016-03-01

    We measured pupillary constrictions in response to full-screen flashes of variable luminance, occurring either at the onset of a saccadic eye movement or well before/after it. A large fraction of perisaccadic flashes were undetectable to the subjects, consistent with saccadic suppression of visual sensitivity. Likewise, pupillary responses to perisaccadic flashes were strongly suppressed. However, the two phenomena appear to be dissociable. Across subjects and luminance levels of the flash stimulus, there were cases in which conscious perception of the flash was completely depleted yet the pupillary response was clearly present, as well as cases in which the opposite occurred. On one hand, the fact that pupillary light responses are subject to saccadic suppression reinforces evidence that this is not a simple reflex but depends on the integration of retinal illumination with complex "extraretinal" cues. On the other hand, the relative independence of pupillary and perceptual responses suggests that suppression acts separately on these systems-consistent with the idea of multiple visual pathways that are differentially affected by saccades. PMID:26745249

  4. Podocyte Depletion in Thin GBM and Alport Syndrome

    PubMed Central

    Wang, Su Q.; Afshinnia, Farsad; Kershaw, David; Wiggins, Roger C.

    2016-01-01

    The proximate genetic cause of both Thin GBM and Alport Syndrome (AS) is abnormal α3, 4 and 5 collagen IV chains resulting in abnormal glomerular basement membrane (GBM) structure/function. We previously reported that podocyte detachment rate measured in urine is increased in AS, suggesting that podocyte depletion could play a role in causing progressive loss of kidney function. To test this hypothesis podometric parameters were measured in 26 kidney biopsies from 21 patients aged 2–17 years with a clinic-pathologic diagnosis including both classic Alport Syndrome with thin and thick GBM segments and lamellated lamina densa [n = 15] and Thin GBM cases [n = 6]. Protocol biopsies from deceased donor kidneys were used as age-matched controls. Podocyte depletion was present in AS biopsies prior to detectable histologic abnormalities. No abnormality was detected by light microscopy at <30% podocyte depletion, minor pathologic changes (mesangial expansion and adhesions to Bowman’s capsule) were present at 30–50% podocyte depletion, and FSGS was progressively present above 50% podocyte depletion. eGFR did not change measurably until >70% podocyte depletion. Low level proteinuria was an early event at about 25% podocyte depletion and increased in proportion to podocyte depletion. These quantitative data parallel those from model systems where podocyte depletion is the causative event. This result supports a hypothesis that in AS podocyte adherence to the GBM is defective resulting in accelerated podocyte detachment causing progressive podocyte depletion leading to FSGS-like pathologic changes and eventual End Stage Kidney Disease. Early intervention to reduce podocyte depletion is projected to prolong kidney survival in AS. PMID:27192434

  5. Syndromes associated with mitochondrial DNA depletion

    PubMed Central

    2014-01-01

    Mitochondrial dysfunction accounts for a large group of inherited metabolic disorders most of which are due to a dysfunctional mitochondrial respiratory chain (MRC) and, consequently, deficient energy production. MRC function depends on the coordinated expression of both nuclear (nDNA) and mitochondrial (mtDNA) genomes. Thus, mitochondrial diseases can be caused by genetic defects in either the mitochondrial or the nuclear genome, or in the cross-talk between the two. This impaired cross-talk gives rise to so-called nuclear-mitochondrial intergenomic communication disorders, which result in loss or instability of the mitochondrial genome and, in turn, impaired maintenance of qualitative and quantitative mtDNA integrity. In children, most MRC disorders are associated with nuclear gene defects rather than alterations in the mtDNA itself. The mitochondrial DNA depletion syndromes (MDSs) are a clinically heterogeneous group of disorders with an autosomal recessive pattern of transmission that have onset in infancy or early childhood and are characterized by a reduced number of copies of mtDNA in affected tissues and organs. The MDSs can be divided into least four clinical presentations: hepatocerebral, myopathic, encephalomyopathic and neurogastrointestinal. The focus of this review is to offer an overview of these syndromes, listing the clinical phenotypes, together with their relative frequency, mutational spectrum, and possible insights for improving diagnostic strategies. PMID:24708634

  6. Recovery of Depleted Uranium Fragments from Soil

    SciTech Connect

    Farr, C.P.; Alecksen, T.J.; Heronimus, R.S.; Simonds, M.H.; Farrar, D.R.; Baker, K.R.; Miller, M.L.

    2008-07-01

    A cost-effective method was demonstrated for recovering depleted uranium (DU) fragments from soil. A compacted clean soil pad was prepared adjacent to a pile of soil containing DU fragments. Soil from the contaminated pile was placed on the pad in three-inch lifts using conventional construction equipment. Each lift was scanned with an automatic scanning system consisting of an array of radiation detectors coupled to a detector positioning system. The data were downloaded into ArcGIS for data presentation. Areas of the pad exhibiting scaler counts above the decision level were identified as likely locations of DU fragments. The coordinates of these locations were downloaded into a PDA that was wirelessly connected to the positioning system. The PDA guided technicians to the locations where hand-held trowels and shovels were used to remove the fragments. After DU removal, the affected areas were re-scanned and the new data patched into the data base to replace the original data. This new data set along with soil sample results served as final status survey data. (authors)

  7. Ozone depletion: 20 Years after the alarm

    SciTech Connect

    Not Available

    1994-08-15

    Scientific curiosity in 1973 led to the challenge of determining the ultimate atmospheric fate of the chlorofluoromethanes, CFC-11 (CCl[sub 3]F) and CFC-12 (CCl[sub 2]F[sub 2]), whose presence at measurable levels in surface air had been detected only two years earlier. In retrospect, the decision to pursue the chemistry of CFC molecules to their final destruction and beyond foreordained an unusual outcome because CFCs are chemically inert and easily survive under almost all natural conditions. By midsummer 1994, the world is well on its way in transition to a CFC-free economy, although not yet to a CFC-free atmosphere. The rates of increase in atmospheric concentration for the three major CFCs (CFC-11, -12, and -113) have all slowed markedly in response to the restrictions of the revised Montreal protocol. Because of their long lifetimes, however, significant but gradually diminishing quantities of CFCs will remain in the atmosphere throughout the 21st century. Atomic chlorine will continue to be released into the stratosphere as long as CFCs persist, and ozone depletion will follow. The existence of the Montreal protocol and the agreement among industrial, governmental, and university scientists on its wisdom offers considerable promise for the handling of future global environmental problems.

  8. Research on mitigation of stratospheric ozone depletion

    SciTech Connect

    Wong, A.Y. )

    1994-08-01

    Chlorine atoms released from CFCs by solar Ultraviolet (UV) radiation and from natural sources, are effective catalytic agents for the destruction of stratospheric ozone. Research into large-scale mitigation methods is based on charging the chlorine radical, converting it into negative ions of low reactivity. Generation of charges-and subsequent removal of chlorine ions by atmospheric platforms and electromagnetic waves are described. This method is generally applicable to all halogens. This research is guided by the principle that the solution should be as non-intrusive environmentally as possible; i.e. no chemicals are to be injected. The large-scale mitigation requires the process to be energy efficient and to utilize energy sources already present in the atmosphere. Because of the wide variety of remediation concepts, each is being tested using a combination of laboratory and field experiments together with computer modeling. The first laboratory demonstration of ozone depletion and subsequent recovery due to charge injection is presented. [copyright][ital American] [ital Institute] [ital of] [ital Physics

  9. Tylosin depletion in edible tissues of turkeys.

    PubMed

    Montesissa, C; De Liguoro, M; Santi, A; Capolongo, F; Biancotto, G

    1999-10-01

    The depletion of tylosin residues in edible turkey tissues was followed after 3 days of administration of tylosin tartrate at 500 mg l-1 in drinking water, to 30 turkeys. Immediately after the end of the treatment (day 0) and at day 1, 3, 5 and 10 of withdrawal, six turkeys (three males and three females) per time were sacrificed and samples of edible tissues were collected. Tissue homogenates were extracted, purified and analysed by HPLC according to a method previously published for the analysis of tylosin residues in pig tissues. In all tissues, tylosin residues were already below the detection limits of 50 micrograms kg-1 at time zero. However, in several samples of tissues (skin + fat, liver, kidney, muscle), from the six turkeys sacrificed at that time, one peak corresponding to an unknown tylosin equivalent was detected at measurable concentrations. The identification of this unknown compound was performed by LC-MS/MS analysis of the extracts from incurred samples. The mass fragmentation of the compound was consistent with the structure of tylosin D (the alcoholic derivative of tylosin A), the major metabolite of tylosin previously recovered and identified in tissues and/or excreta from treated chickens, cattle and pigs. PMID:10755131

  10. STRV Cryocooler Tip Motion Suppression

    NASA Technical Reports Server (NTRS)

    Glaser, R.; Ross, R. G., Jr.; Johnson, D. L.

    1994-01-01

    The Space Technology Research Vehicle (STRV-1b) scheduled to fly at the beginning of June 1994, has a cryocooler vibration suppression experiment aboard doing motion suppression of the tip of the coldfinger. STRV-1b is a bread box sized satellite to be launched on the next flight of the Ariane-4.

  11. An Alternative to Thought Suppression?

    ERIC Educational Resources Information Center

    Boice, Robert

    2012-01-01

    Comments on the original article, "Setting free the bears: Escape from thought suppression," by D. M. Wegner (see record 2011-25622-008). While Wegner supposed that we might have to learn to live with bad thoughts, the present author discusses the use of imagination and guided imagery as an alternative to forced thought suppression.

  12. Nonanesthetics can suppress learning.

    PubMed

    Kandel, L; Chortkoff, B S; Sonner, J; Laster, M J; Eger, E I

    1996-02-01

    Nonanesthetic gases or vapors do not abolish movement in response to noxious stimuli despite partial pressures and affinities for lipids that would, according to the Meyer-Overton hypothesis, predict such abolition. We investigated whether nonanesthetics depress learning and memory (i.e., provide amnesia). To define learning, we used a "fear-potentiated startle paradigm": rats trained to associate light with a noxious stimulus (footshock) will startle more, as measured by an accelerometer, when a startle-eliciting stimulus (e.g., a noise) is paired with light than when the startle-eliciting stimulus is presented alone. We imposed light-shock pairings on 98 rats under three conditions: no anesthesia (control); 0.20, 0.29, and 0.38 times the minimum alveolar anesthetic concentration (MAC) of desflurane; or two nonanesthetics (1,2-dichloroperfluorocyclobutane and perfluoropentane) at partial pressures predicted from their lipid solubilities to be between 0.2 and 1 MAC. Desflurane produced a dose-related depression of learning with abolition of learning at 0.28 MAC. Perfluoropentane at 0.2-predicted MAC had the same effect as 0.28 MAC desflurane. 1,2-Dichloroperfluorocyclobutane at 0.5- to 1-predicted MAC abolished learning. Because nonanesthetics suppress learning but not movement (the two critical components of anesthesia), they may prove useful in discriminating between mechanisms and sites of action of anesthetics. PMID:8561335

  13. Inducing amnesia through systemic suppression.

    PubMed

    Hulbert, Justin C; Henson, Richard N; Anderson, Michael C

    2016-01-01

    Hippocampal damage profoundly disrupts the ability to store new memories of life events. Amnesic windows might also occur in healthy people due to disturbed hippocampal function arising during mental processes that systemically reduce hippocampal activity. Intentionally suppressing memory retrieval (retrieval stopping) reduces hippocampal activity via control mechanisms mediated by the lateral prefrontal cortex. Here we show that when people suppress retrieval given a reminder of an unwanted memory, they are considerably more likely to forget unrelated experiences from periods surrounding suppression. This amnesic shadow follows a dose-response function, becomes more pronounced after practice suppressing retrieval, exhibits characteristics indicating disturbed hippocampal function, and is predicted by reduced hippocampal activity. These findings indicate that stopping retrieval engages a suppression mechanism that broadly compromises hippocampal processes and that hippocampal stabilization processes can be interrupted strategically. Cognitively triggered amnesia constitutes an unrecognized forgetting process that may account for otherwise unexplained memory lapses following trauma. PMID:26977589

  14. Inducing amnesia through systemic suppression

    PubMed Central

    Hulbert, Justin C.; Henson, Richard N.; Anderson, Michael C.

    2016-01-01

    Hippocampal damage profoundly disrupts the ability to store new memories of life events. Amnesic windows might also occur in healthy people due to disturbed hippocampal function arising during mental processes that systemically reduce hippocampal activity. Intentionally suppressing memory retrieval (retrieval stopping) reduces hippocampal activity via control mechanisms mediated by the lateral prefrontal cortex. Here we show that when people suppress retrieval given a reminder of an unwanted memory, they are considerably more likely to forget unrelated experiences from periods surrounding suppression. This amnesic shadow follows a dose-response function, becomes more pronounced after practice suppressing retrieval, exhibits characteristics indicating disturbed hippocampal function, and is predicted by reduced hippocampal activity. These findings indicate that stopping retrieval engages a suppression mechanism that broadly compromises hippocampal processes and that hippocampal stabilization processes can be interrupted strategically. Cognitively triggered amnesia constitutes an unrecognized forgetting process that may account for otherwise unexplained memory lapses following trauma. PMID:26977589

  15. Sound can suppress visual perception.

    PubMed

    Hidaka, Souta; Ide, Masakazu

    2015-01-01

    In a single modality, the percept of an input (e.g., voices of neighbors) is often suppressed by another (e.g., the sound of a car horn nearby) due to close interactions of neural responses to these inputs. Recent studies have also suggested that close interactions of neural responses could occur even across sensory modalities, especially for audio-visual interactions. However, direct behavioral evidence regarding the audio-visual perceptual suppression effect has not been reported in a study with humans. Here, we investigated whether sound could have a suppressive effect on visual perception. We found that white noise bursts presented through headphones degraded visual orientation discrimination performance. This auditory suppression effect on visual perception frequently occurred when these inputs were presented in a spatially and temporally consistent manner. These results indicate that the perceptual suppression effect could occur across auditory and visual modalities based on close and direct neural interactions among those sensory inputs. PMID:26023877

  16. Involvement of molecular oxygen in the donor-side photoinhibition of Mn-depleted photosystem II membranes.

    PubMed

    Khorobrykh, A A; Klimov, V V

    2015-12-01

    It has been shown by Khorobrykh et al. (Biochemistry (Moscow) 67:683-688, 2002); Yanykin et al. (Biochim Biophys Acta 1797:516-523, 2010); Khorobrykh et al. (Biochemistry 50:10658-10665, 2011) that Mn-depleted photosystem II (PSII) membrane fragments are characterized by an enhanced oxygen photoconsumption on the donor side of PSII which is accompanied with hydroperoxide formation and it was suggested that the events are related to the oxidative photoinhibition of PSII. Experimental confirmation of this suggestion is presented in this work. The degree of photoinhibition was determined by the loss of the capability of exogenous electron donors (Mn(2+) or sodium ascorbate) to the reactivation of electron transport [measured by the light-induced changes of chlorophyll fluorescence yield (∆F)] in Mn-depleted PSII membranes. The transition from anaerobic conditions to aerobic ones significantly activated photoinhibition of Mn-depleted PSII membranes both in the absence and in the presence of exogenous electron acceptor, ferricyanide. The photoinhibition of Mn-depleted PSII membranes was suppressed upon the addition of exogenous electron donors (Mn(2+), diphenylcarbazide, and ferrocyanide). The addition of superoxide dismutase did not affect the photoinhibition of Mn-depleted PSII membranes. It is concluded that the interaction of molecular oxygen (rather than superoxide anion radical formed on the acceptor side of PSII) with the oxidized components of the donor side of PSII reflects the involvement of O2 in the donor-side photoinhibition of Mn-depleted PSII membranes. PMID:25862644

  17. Depletion of C3orf1/TIMMDC1 inhibits migration and proliferation in 95D lung carcinoma cells.

    PubMed

    Wu, Huiling; Wang, Wenbing; Xu, Huaxi

    2014-01-01

    In our previous study, we identified an association of high expression of c3orf1, also known as TIMMDC1 (translocase of inner mitochondrial membrane domain-containing protein 1), with metastatic characteristics in lung carcinoma cells. To investigate the preliminary function and mechanism of this mitochondrial protein, we depleted C3orf1 expression by introducing siRNA into 95D lung carcinoma cells. We demonstrated that C3orf1 depletion significantly suppressed 95D cell growth and migration. We confirmed C3orf1 localization in the inner mitochondrial membrane and showed that mitochondrial viability, membrane potential, and ATPase activity were remarkably reduced upon depletion of C3orf1. Microarray data indicated that genes involved in regulation of cell death, migration, and cell-cycle arrest were significantly altered after C3orf1 depletion for 48 h. The expression of genes involved in focal adhesion, ECM-receptor interaction, and p53-signaling pathways were notably altered. Furthermore, cell-cycle arrest genes such as CCNG2 and PTEN as well as genes involved in cell migration inhibition, such as TIMP3 and COL3A1, were upregulated after C3orf1 depletion in 95D cells. Concurrently, expression of the migration-promoting gene NUPR1 was markedly reduced, as confirmed by real-time PCR. We conclude that C3orf1 is critical for mitochondrial function, migration, and proliferation in 95D lung carcinoma cells. Depletion of C3orf1 inhibited cell migration and cell proliferation in association with upregulation of genes involved in cell-cycle arrest and cell migration inhibition. These results suggest that C3orf1 (TIMMDC1) may be a viable treatment target for lung carcinoma, and that further study of the role of this protein in lung carcinoma pathogenesis is justified. PMID:25391042

  18. BENZENE VAPOR DEPLETION IN THE PRESENCE OF PLANTS

    EPA Science Inventory

    Three plant species, Eichhornia crassipes in a nutrient hydroponic culture Beta vulgaris saccharifera, and Beta vulgaris cicla in soil and in water cultures, were found to deplete benzene from the air. Following benzene depletion, plant tissues were extracted and no benzene was d...

  19. Auto-aligning stimulated emission depletion microscope using adaptive optics

    PubMed Central

    Gould, Travis J.; Kromann, Emil B.; Burke, Daniel; Booth, Martin J.; Bewersdorf, Joerg

    2013-01-01

    Stimulated emission depletion (STED) microscopy provides diffraction-unlimited resolution in fluorescence microscopy. Imaging at the nanoscale, however, requires precise alignment of the depletion and excitation laser foci of the STED microscope. We demonstrate here that adaptive optics can be implemented to automatically align STED and confocal images with a precision of 4.3 ± 2.3 nm. PMID:23722769

  20. LINKAGE BETWEEN CLIMATE CHANGE AND STRATOSPHERIC OZONE DEPLETION

    EPA Science Inventory

    Two primary areas link the issue of stratospheric ozone depletion to global climate change: atmospheric processes and ecological processes. tmospheric processes establish a linkage through the dual roles of certain trace gases in promoting global warming and in depleting the ozon...

  1. Optimal Allocation of Sampling Effort in Depletion Surveys

    EPA Science Inventory

    We consider the problem of designing a depletion or removal survey as part of estimating animal abundance for populations with imperfect capture or detection rates. In a depletion survey, animals are captured from a given area, counted, and withheld from the population. This proc...

  2. Influence of Roller Burnishing Parameters on Depletion of Plasticity Reserve

    NASA Astrophysics Data System (ADS)

    Blumenstein, V. Yu; Petrenko, K. P.

    2016-04-01

    Roller burnishing process considerably increases surface quality and service life of machine parts. Efficiency of roller burnishing rises greatly when technological inheritance (TI) is taken into account. Research results of degree of plasticity reserve depletion (DPRD) while roller burnishing are presented. Results obtained made it possible to establish mechanisms of strain accumulation and plasticity reserve depletion according to roller burnishing parameters.

  3. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 7 2010-04-01 2010-04-01 true Percentage depletion; general rule. 1.613-1 Section 1.613-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion;...

  4. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 7 2011-04-01 2009-04-01 true Percentage depletion; general rule. 1.613-1 Section 1.613-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion; general rule. (a) In general. In the case of a...

  5. In vivo evidence for CD4+ and CD8+ suppressor T cells in vaccination-induced suppression of murine experimental autoimmune thyroiditis

    SciTech Connect

    Flynn, J.C.; Kong, Y.C. )

    1991-09-01

    In several experimental autoimmune diseases, including experimental autoimmune thyroiditis (EAT), vaccination with attenuated autoantigen-specific T cells has provided protection against subsequent induction of disease. However, the mechanism(s) of vaccination-induced suppression remains to be clarified. Since the authors have previously shown that suppression generated by pretreatment with mouse thyroglobulin (MTg) or thyroid-stimulating hormone in EAT is mediated by CD4+, not CD8+, suppressor T cells, they examined the role of T cell subsets in vaccination-induced suppression of EAT. Mice were vaccinated with irradiated, MTg-primed, and MTg-activated spleen cells and then challenged. Pretreatment with these cells suppressed EAT induced by immunization with MTg and adjuvant, but not by adoptive transfer of thyroiditogenic cells, suggesting a mechanism of afferent suppression. The activation of suppressor mechanisms did not require CD8+ cells, since mice depleted of CD8+ cells before vaccination showed reduced EAT comparable to control vaccinated mice. Furthermore, depletion of either the CD4+ or the CD8+ subset after vaccination did not significantly abrogate suppression. However, suppression was eliminated by the depletion of both CD4+ and CD8+ cells in vaccinated mice. These results provide evidence for the cooperative effects of CD4+ and CD8+ T cells in vaccination-induced suppression of EAT.

  6. Tumor growth suppression by the combination of nanobubbles and ultrasound.

    PubMed

    Suzuki, Ryo; Oda, Yusuke; Omata, Daiki; Nishiie, Norihito; Koshima, Risa; Shiono, Yasuyuki; Sawaguchi, Yoshikazu; Unga, Johan; Naoi, Tomoyuki; Negishi, Yoichi; Kawakami, Shigeru; Hashida, Mitsuru; Maruyama, Kazuo

    2016-03-01

    We previously developed novel liposomal nanobubbles (Bubble liposomes [BL]) that oscillate and collapse in an ultrasound field, generating heat and shock waves. We aimed to investigate the feasibility of cancer therapy using the combination of BL and ultrasound. In addition, we investigated the anti-tumor mechanism of this cancer therapy. Colon-26 cells were inoculated into the flank of BALB/c mice to induce tumors. After 8 days, BL or saline was intratumorally injected, followed by transdermal ultrasound exposure of tumor tissue (1 MHz, 0-4 W/cm2 , 2 min). The anti-tumor effects were evaluated by histology (necrosis) and tumor growth. In vivo cell depletion assays were performed to identify the immune cells responsible for anti-tumor effects. Tumor temperatures were significantly higher when treated with BL + ultrasound than ultrasound alone. Intratumoral BL caused extensive tissue necrosis at 3-4 W/cm2 of ultrasound exposure. In addition, BL + ultrasound significantly suppressed tumor growth at 2-4 W/cm2 . In vivo depletion of CD8+ T cells (not NK or CD4+ T cells) completely blocked the effect of BL + ultrasound on tumor growth. These data suggest that CD8+ T cells play a critical role in tumor growth suppression. Finally, we concluded that BL + ultrasound, which can prime the anti-tumor cellular immune system, may be an effective hyperthermia strategy for cancer treatment. PMID:26707839

  7. Barium depletion study on impregnated cathodes and lifetime prediction

    NASA Astrophysics Data System (ADS)

    Roquais, J. M.; Poret, F.; le Doze, R.; Ricaud, J. L.; Monterrin, A.; Steinbrunn, A.

    2003-06-01

    In the thermionic cathodes used in cathode ray-tubes (CRTs), barium is the key element for the electronic emission. In the case of the dispenser cathodes made of a porous tungsten pellet impregnated with Ba, Ca aluminates, the evaporation of Ba determines the cathode lifetime with respect to emission performance in the CRT. The Ba evaporation results in progressive depletion of the impregnating material inside the pellet. In the present work, the Ba depletion with time has been extensively characterized over a large range of cathode temperature. Calculations using the depletion data allowed modeling of the depletion as a function of key parameters. The link between measured depletion and emission in tubes has been established, from which an end-of-life criterion was deduced. Taking modeling into account, predicting accelerated life-tests were performed using high-density maximum emission current (MIK).

  8. The timing and mechanism of depletion in Lewisian granulites

    NASA Technical Reports Server (NTRS)

    Cohen, A. S.; Onions, R. K.; Ohara, M. J.

    1988-01-01

    Large Ion Lithophile (LIL) depletion in Lewisian granulites is discussed. Severe depletions in U, Th, and other LIL have been well documented in Lewisan mafic and felsic gneisses, but new Pb isotopic analyses show little or no depletion in lithologies with high solidus temperatures, such as peridotite. This suggests that LIL transport in this terrane took place by removal of partial melts rather than by pervasive flooding with externally derived CO2. The Pb and Nd isotopic data gathered on these rocks show that the depletion and granulite metamorphism are distinct events about 250 Ma apart. Both fluid inclusions and cation exchange geothermometers date from the later metamorphic event and therefore have little bearing on the depletion event, suggesting a note of caution for interpretations of other granulite terranes.

  9. Charged micelle depletion attraction and interfacial colloidal phase behavior.

    PubMed

    Iracki, Tara D; Beltran-Villegas, Daniel J; Eichmann, Shannon L; Bevan, Michael A

    2010-12-21

    Ensemble total internal reflection microscopy (TIRM) is used to directly measure the evolution of colloid-surface depletion attraction with increasing sodium dodecyl sulfate (SDS) concentration near the critical micelle concentration (CMC). Measured potentials are well described by a modified Asakura-Oosawa (AO) depletion potential in addition to electrostatic and van der Waals contributions. The modified AO potential includes effects of electrostatic interactions between micelles and surfaces via effective depletant dimensions in an excluded volume term and partitioning in an osmotic pressure term. Directly measured colloid-surface depletion potentials are used in Monte Carlo (MC) simulations to capture video microscopy (VM) measurements of micelle-mediated quasi-two-dimensional phase behavior including fluid, crystal, and gel microstructures. Our findings provide information to develop more rigorous and analytically simple models of depletion attraction in charged micellar systems. PMID:21077612

  10. Ionogram range/time plots, satellite traces and optical depletions

    NASA Astrophysics Data System (ADS)

    Lynn, Kenneth; Shiokawa, Kazuo; Otsuka, Yuichi; Wilkinson, Phil

    2012-07-01

    Range/time plots derived from 5 minute ionograms have a variety of uses including finding TIDs, following major height variations in the F2 ionosphere and tracking the movement of low latitude electron depletions as verified by co-incident observations by optical methods. This paper investigates these applications with particular emphasis on following optical depletions via ionosonde as observed at Darwin, Australia. Similar additional range/time plots are also discussed from Vanimo and Port Moresby in New Guinea and Tennant Creek and Townsville in Australia. While much theoretical work has been expended on explaining the development of equatorial bubble/depletions, current work highlights the apparently strong development of depletions at times of year when the pre-sunset height rise and following fall is minimal in contrast to current conventional thinking. In contrast, depletions are not observed at Australian equatorial longitudes when the pre- and post- sunset height variations are greatest in magnitude and consistency.